@string{acm="Association for Computing Machinery"}
@string{bell="Bell Laboratories"}
@string{dec="Digital Equipment Corporation"}
@string{ibm="IBM"}
@string{ibmsj="IBM San Jose Research Center"}
@string{parc="Xerox Palo Alto Research Center"}
@string{sigmod="SIGMod"}
@string{sigplan="SIGPlan"}
@string{cmucsd="Computer Science Department, Carnegie Mellon University"}
@string{mitcsd="Department of Computer Science, Massachusettes Institute of Technology"}
@string{stanfordcsd="Computer Science Department, Stanford University"}
@string{ucbcsd="Computer Science Department, University of California at Berkeley"}
@string{unccsd="Computer Science Department, University of North Carolina at Chapel Hill"}
@string{bell="Bell Laboratories"}
@string{dec="Digital Equipment Corporation"}
@string{ibmsj="IBM San Jose Research Center"}
@string{parc="Xerox Palo Alto Research Center"}
@string{cmucsd="Computer Science Department, Carnegie Mellon University"}
@string{mit="Department of Computer Science, Massachusettes Institute of Technology"}
@string{stanfordcsd="Computer Science Department, Stanford University"}
@string{uazcsd="Computer Science Department, University of Arizona"}
@string{ucbcsd="Computer Science Department, University of California at Berkeley"}
@string{unccsd="Computer Science Department, University of North Carolina at Chapel Hill"}
@string{acm="Association for Computing Machinery"}
@string{bell="Bell Laboratories"}
@string{dec="Digital Equipment Corporation"}
@string{ibmsj="IBM San Jose Research Center"}
@string{parc="Xerox Palo Alto Research Center"}
@string{cmucsd="Computer Science Department, Carnegie Mellon University"}
@string{mitcsd="Department of Computer Science, Massachusettes Institute of Technology"}
@string{stanfordcsd="Computer Science Department, Stanford University"}
@string{uazcsd="Computer Science Department, University of Arizona"}
@string{ucbcsd="Computer Science Department, University of California at Berkley"}
@string{unccsd="Computer Science Department, University of North Carolina at Chapel Hill"}
@string{aim="Artificial Intelligence Memo"}
@string{aitr="Artificial Intelligence Technical Report"}
@string{tn="Technical Note"}
@string{cmucsd="Computer Science Department, Carnegie Mellon University"}
@string{mitcsd="Department of Computer Science, Massachusettes Institute of Technology"}
@string{stanfordcsd="Computer Science Department, Stanford University"}
@string{uazcsd="Computer Science Department, University of Arizona"}
@string{ucbcsd="Computer Science Department, University of California at Berkeley"}
@string{unccsd="Computer Science Department, University of North Carolina at Chapel Hill"}
@string{ai="Artificial Intelligence"}
@string{bstj="Bell System Technical Journal"}
@string{cacm="Communications of the Association of Computing Machinery"}
@string{cgip="Computer Graphics and Image Processing"}
@string{comprev="ACM Computing Reviews"}
@string{compsurv="ACM Computing Surveys"}
@string{ibmsj="IBM Systems Journal"}
@string{ieee="IEEE"}
@string{jacm="Journal of the Association of Computing Machinery"}
@string{jssc="IEEE Journal of Solid-State Circuits"}
@string{opsysrev="ACM Operating Systems Review"}
@string{procieee="Proceedings of the IEEE"}
@string{sigmod="ACM SIGMOD Record"}
@string{sigplan="ACM SIGPlan Notices"}
@string{spe="Software--Practice and Experience"}
@string{tc="IEEE Transactions on Computers"}
@string{tkde="IEEE Transactions on Knowledge and Data Engineering"}
@string{tocs="ACM Transactions on Computer Systems"}
@string{tods="ACM Transactions on Database Systems"}
@string{tog="ACM Transactions on Graphics"}
@string{toplas="ACM Transactions on Programming Languages and Systems"}
@string{tse="IEEE Transactions on Software Engineering"}
@string{fjcc="Proceedings of the AFIPS Fall Joint Computer Conference"}
@string{ijcai="Proceedings of the International Joint Conference on Artificial Intelligence"}
@string{ncc="Proceedings of the AFIPS National Computer Conference"}
@string{pods="Proceedings of the ACM Symposium on Principles of Database Systems"}
@string{popl="Proceedings of the ACM Symposium on Principles of Programming Languages"}
@string{sigmod="Proceedings of ACM SIGMOD International Conference on Management of Data"}
@string{sjcc="Proceedings of the AFIPS Spring Joint Computer Conference"}
@string{sosp="Proceedings of the ACM Symposium on Operating System Principles"}
@string{vldb="Proceedings of the Conference on Very Large Databases"}
@string{chdl6="Proceedings of the IFIP WG 10.2 Sixth International Conference on Computer Hardware Description Languages and their Applications"}
@string{chdl5="Proceedings of the IFIP TC-10 Fifth International Conference on Computer Hardware Description Languages and Their Applications"}
@string{chdl3="1975 International Symposium on Computer Hardware Description Languages and Their Applications Proceedings"}
@string{dac5="5th Design Automation Workshop Proceedings"}
@string{dac8="8th Design Automation Workshop Proceedings"}
@string{dac10="10th Design Automation Workshop Proceedings"}
@string{dac11="11th Design Automation Workshop Proceedings"}
@string{dac14="14th Design Automation Conference Proceedings"}
@string{dac15="15th Design Automation Conference Proceedings"}
@string{dac16="16th Design Automation Conference Proceedings"}
@string{dac17="17th Design Automation Conference Proceedings"}
@string{dac18="18th Design Automation Conference Proceedings"}
@string{dac19="19th Design Automation Conference Proceedings"}
@string{dac20="20th Design Automation Conference Proceedings"}
@string{dac21="21st Design Automation Conference Proceedings"}
@string{dac22="22nd Design Automation Conference Proceedings"}
@string{jan="January"}
@string{feb="February"}
@string{mar="March"}
@string{apr="April"}
@string{may="May"}
@string{jun="June"}
@string{jul="July"}
@string{aug="August"}
@string{sep="September"}
@string{oct="October"}
@string{nov="November"}
@string{dec="December"}

@Comment(BIBTEMPLATE .)
@Comment(BIBREFERENCES stdalphabetic)
@Comment{BIBSEPARATORS ",;"}


@unpublished	( ABHYANKAR87,
key	=	"Abhyankar \& Kashyap" ,
author	=	"Abhyankar, R. B. and Kashyap, R. L." ,
title	=	"{I}ncomplete {I}nformation and the {R}elational {M}odel of
{D}ata" ,
note	=	"Submitted to SIGMOD 87" ,
)

@inproceedings	( ABITEBOUL85A,
key	=	"Abiteboul" ,
author	=	"Abiteboul, S. and Grahne, G." ,
title	=	"{U}pdate semantics for incomplete databases" ,
booktitle=	vldb ,
address	=	"Stockholm, Sweden" ,
month	=	aug ,
year	=	"1985" ,
pages	=	"1--12" ,
abstract=	"A database containing some incomplete information
is viewed as a set of possible states of the real world. The semantics
of updates is given based on simple set operations on the set of
states. Some basic results concerning the capabilities of known models
of incomplete databases to handle updates are exhibited." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( ABITEBOUL87A,
key	=	"Abiteboul et al." ,
author	=	"Abiteboul, S. and Kanellakis, P. and Grahne, G." ,
title	=	"{O}n the {R}epresentation and {Q}uerying of {S}ets of
{P}ossible {W}orlds" ,
booktitle=	sigmod ,
organization=	acm ,
publisher=	"ACM Press" ,
address	=	"San Francisco, CA" ,
editor	=	"Dayal, U. and Traiger, I." ,
month	=	may ,
year	=	"1987" ,
pages	=	"34--48" ,
abstract=	"We represent a set of possible worlds using an
incomplete information database. The representation techniques that we
study form a hierarchy, which generalizes relations of constants. This
hierarchy ranges from the very simple Codd-table, (i.e., a relation of
constants and distinct variables called nulls, which stand for values
present but unknown), to much more complex mechanisms involving views
on conditioned-tables, (i.e., queries on Codd-tables together with
conditions.) The views we consider are the queries that have
polynomial data-complexity on complete information databases. Our
conditions are conjunctions of equalities and inequalities. (1) We
provide matching upper and lower bounds on the data-complexity of
testing containment, membership, and uniqueness for sets of possible
worlds and we fully classify these problems with respect to our
representation hierarchy. The most surprising result in this
classification is that: it is complete in $\{Pi_2}^{p}$, whether a set
of possible worlds represented by a Codd-table with one conjunction of
inequalities. (2) We investigate the data-complexity of querying
incomplete information databases. We examine both asking for certain
facts and for possible facts. Our approach is algebraic but our bounds
also apply to logical databases. We show that asking for a certain
fact is coNP-complete, even for a fixed first order query on a
Codd-table. We thus strengthen a lower bound of [16], who showed that
this holds for a Codd-table with a conjunction of inequalities. For
each fixed positive existential query we present a polynomial
algorithm solving the bounded possible fact problem of this query on
conditioned-tables. We show that our approach is, in a sense, the best
possible, by deriving two NP-completeness lower bounds for the bounded
possible fact problem: when the fixed query contains either negation
or recursion." ,
bibdate	=	"Fri Jul 24 14:17:36 1987" ,
owner	=	"manning" ,
)

@article	( ABITEBOUL91,
key	=	"Abiteboul et al." ,
author	=	"Abiteboul, S. and Kanellakis, P. and Grahne, G." ,
title	=	"{O}n the {R}epresentation and {Q}uerying of {S}ets of
{P}ossible {W}orlds" ,
journal	=	"Theoretical Computer Science" ,
volume	=	"78" ,
number	=	"1" ,
month	=	jan ,
year	=	"1991" ,
pages	=	"159--187" ,
abstract=	"We represent a set of possible worlds using an
incomplete information database. The representation techniques that we
study ranges from the very simple Codd-table, (i.e., a relation of
constants and uniquely occurring variables called nulls), to much more
complex mechanisms involving views on conditioned-tables (programs
applied to Codd-tables augmented by equality and inequality
conditions). (1) We provide matching upper and lower bounds on the
data-complexity of testing containment, membership, and uniqueness for
sets of possible worlds. We fully classify these problems with respect
to our representations. (2) We investigate the data-complexity of
querying incomplete information databases for both possible and
certain facts. For each fixed positive existential query on
conditioned-tables we present a polynomial time algorithm solving the
possible fact problem. We match this upper bound by two
NP-completeness lower bounds, when the fixed query contains either
negation or recursion and is applied to Codd-tables. We show that
asking for a certain fact is coNP-complete, even for a fixed first
order query applied to a Codd-table." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( ANFINDSEN92,
key	=	"Anfindsen" ,
author	=	"Anfindsen, O. J." ,
title	=	"{M}ultivalued {L}ogic and {D}atabase {S}ystems" ,
type	=	"TR" ,
number	=	"R 41/92" ,
institution=	"Norwegian Telecom Research" ,
year	=	"1992" ,
month	=	oct ,
abstract=	"to enter" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( ANVARI84,
key	=	"Anvari \& Rose" ,
author	=	"Anvari, M. and Rose, G. F." ,
title	=	"{F}uzzy {R}elational {D}atabases" ,
booktitle=	"Proceedings of the 1st International Conference on
Fuzzy Information Processing" ,
address	=	"Kuaui, HI" ,
year	=	"1984" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( ANVARI87,
key	=	"Anvari \& Rose" ,
author	=	"Anvari, M. and Rose, G. F." ,
title	=	"{F}uzzy {R}elational {D}atabases" ,
booktitle=	"Analysis of Fuzzy Information" ,
pages	=	"203--212" ,
volume	=	"2" ,
year	=	"1987" ,
abstract=	"do not have article " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( ANWAR92B,
key	=	"Anwar et al." ,
author	=	"Anwar, T. M. and Beck, H. W. and Navathe, S. B." ,
title	=	"{K}nowledge {M}ining by {I}mprecise {Q}uerying: {A}
{C}lassification-based {S}ystem" ,
booktitle=	"Proceedings of the International Conference on
Data Engineering" ,
address	=	"Tempe, AZ" ,
month	=	feb ,
year	=	"1992" ,
pages	=	"622--630" ,
abstract=	"Knowledge mining is the process of discovering new
knowledge that is hitherto unknown. Users with a lack of knowledge of
database schemas engage in the process of knowledge mining by posing
imprecise queries. An approach to knowledge mining by imprecise
querying is presented that utilizes conceptual clustering techniques.
In contrast to numeric or fuzzy set approaches which ultimately rely
on some distance metric and threshold to processing such queries,
conceptual clustering retrieves instances which are structurally,
semantically, and pragmatically similar to the query even though they
may not match the requirements exactly. The query processor has both a
deductive and inductive component. The deductive component finds
precise matches in the traditional sense, and the inductive component
identifies ways in which imprecise matches may be considered similar.
Ranking on similarity is done using the database taxonomy, by which
similar instances become members of the same class. Relative
similarity is determined by depth in the taxonomy. The conceptual
clustering algorithm, its use in query processing and an example are
presented." ,
bibdate	=	"Fri Sep  4 22:04:09 1992" ,
owner	=	"leoso" ,
)

@article	( ARRAZOLA89,
key	=	"Arrazola et al." ,
author	=	"Arrazola, I. and Plainfosse, A. and Prade, H. and
Testemale, C." ,
title	=	"{E}xtrapolation of fuzzy values from incomplete data
bases" ,
journal	=	"Information Sciences" ,
volume	=	"14" ,
number	=	"6" ,
pages	=	"???--???" ,
year	=	"1989" ,
abstract=	" This paper presents different approaches which
enable a data base management system to obtain a plausible fuzzy
estimate for an attribute value of an item for which the information
is not explicity stored in the data base. This can be made either by a
kind of analogical reasoning from information about particular items
or by means of expert rules which specify the (fuzzy) sets of possible
values of the attribute under consideration, for various classes of
items. Another kind of expert rules enables the system to computer an
estimate from the attribute value of another item provided that, in
other respects, this latter item sufficiently resembles the item, the
value of which we are interested in; then these expert rules are used
either for controlling the analogical reasoning process or for
enlarging the scope of application of the first kind of expert rules.
The different approaches are discussed in the framework of possibility
theory. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( ATZENI87,
key	=	"Atzeni \& DeBernardis" ,
author	=	"Atzeni, P. and DeBernardis, M. C." ,
title	=	"{A} new basis for the weak instance model" ,
booktitle=	pods ,
year	=	"1987" ,
pages	=	"79--86" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( ATZENI89,
key	=	"Atzeni \& Torlone" ,
author	=	"Atzeni, P. and Torlone, R." ,
title	=	"{A}pproaches to {U}pdates over {W}eak {I}nstances" ,
year	=	"1989" ,
booktitle=	"Proc. First Symposium on Mathematical Fundamentals
of Database Systems" ,
address	=	"Visegrad, Hungary" ,
pages	=	"12--23" ,
month	=	jun ,
)

@article	( ATZENI90,
key	=	"Atzeni \& DeBernardis" ,
author	=	"Atzeni, P. and DeBernardis, M. C." ,
title	=	"{N}ew {I}nterpretation for {N}ull {V}alues in the {W}eak
{I}nstance {M}odel" ,
journal	=	"Journal of Computer and System Sciences" ,
volume	=	"41" ,
number	=	"1" ,
month	=	aug ,
year	=	"1990" ,
pages	=	"25--43" ,
abstract=	" A new definition of the weak instance model for
relational databases is presented, which does not consider the missing
values as existent though unknown, but just assumes that no
information is available about them. It is possible to associate with
the new definition logical theories that do not contain existentially
quantified variables. The new model enjoys various desirable
properties of the classic weak instance model, with respect to
dependency satisfaction, query answering, and associated logical
theories. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inbook		( ATZENI93,
key	=	"Atzeni \& Antonellis" ,
author	=	"Atzeni, P. and De Antonellis, V." ,
title	=	"{T}he {T}heory of {N}ull {V}alues" ,
booktitle=	"Relational Database Theory" ,
chapter	=	"6" ,
abstract=	"none" ,
publisher=	"The Benjamin/Cummings Publishing Company, Inc." ,
year	=	"1993" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BABAD84,
key	=	"Babad \& Hoffer" ,
author	=	"Babad, Y. M. and Hoffer, J. A." ,
title	=	"{E}ven no data has a value" ,
year	=	"1984" ,
journal	=	cacm ,
volume	=	"27" ,
pages	=	"748--756" ,
number	=	"8" ,
)

@article	( BALDWIN84,
key	=	"Baldwin \& Zhou" ,
author	=	"Baldwin, J. F. and Zhou, S. Q." ,
title	=	"{A} {F}uzzy {R}elational {I}nference {L}anguage" ,
journal	=	"Fuzzy Sets \& Systems" ,
volume	=	"14" ,
year	=	"1984" ,
pages	=	"155--174" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( BARBARA89,
key	=	"Barbar\'{a} et al." ,
author	=	"Barbar\'{a}, D. and Garc\'{\i}a--Molina, H. and
Porter, D." ,
title	=	"{A} {P}robabilistic {R}elational {D}ata {M}odel" ,
type	=	"TR" ,
number	=	"215--89" ,
institution=	"Princeton University" ,
year	=	"1989" ,
month	=	jan ,
abstract=	"It is often desirable to represent in a database
entities whose properties cannot be deterministically classified. We
develop a new data model that includes probabilities associated with
the values of the attributes. The notion of missing probabilities is
introduced for partially specified probability distributions. This new
model offers a richer descriptive language allowing the database to
more accurately reflect the uncertain real world. Probabilistic
analogs to the basic relational operators are defined and their
correctness is studied." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BARBARA90,
key	=	"Barbar\'{a} et al." ,
author	=	"Barbar\'{a}, D. and Garc\'{\i}a--Molina, H. and
Porter, D." ,
title	=	"{A} {P}robabilistic {R}elational {D}ata {M}odel" ,
booktitle=	"Proceedings of the International Conference on
Extending Database Technology: Advances in Database Technology ---
EDBT '90" ,
address	=	"Venice, Italy" ,
month	=	mar ,
year	=	"1990" ,
pages	=	"60--74" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BARBARA92,
key	=	"Barbar\'{a} et al." ,
author	=	"Barbar\'{a}, D. and Garc\'{\i}a--Molina, H. and
Porter, D." ,
title	=	"{T}he {M}anagement of {P}robabilistic {D}ata" ,
journal	=	tkde ,
volume	=	"4" ,
number	=	"5" ,
month	=	oct ,
year	=	"1992" ,
pages	=	"487--502" ,
abstract=	" " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@book		( BEZDEK87,
key	=	"Bezdek" ,
author	=	"Bezdek" ,
title	=	"{A}nalysis of {F}uzzy {I}nformation (3-volume set)" ,
publisher=	"CRC Press" ,
year	=	"1987" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BISKUP79,
key	=	"Biskup" ,
author	=	"Biskup, J." ,
title	=	"{A} formal approach to null values in database
relations" ,
booktitle=	"Workshop: Formal Bases for Databases" ,
editor	=	"H. Gallaire and J.M. Nicolas" ,
address	=	"Toulouse, France" ,
month	=	dec ,
year	=	"1979" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( BISKUP81,
key	=	"Biskup" ,
author	=	"Biskup, J." ,
title	=	"{A} {F}ormal {A}pproach to {N}ull {V}alues in {D}atabase
{R}elations" ,
booktitle=	"Advances in Data Base Theory" ,
editor	=	"H. Gallaire and J. Minker and J. Nicolas" ,
publisher=	"Plenum Press" ,
address	=	"New York" ,
year	=	"1981" ,
volume	=	"1" ,
pages	=	"299--341" ,
abstract=	"We study the problem of null values. By this we
mean that an attribute is applicable but its value at present is
unknown and also that an attribute is applicable but its value is
arbitrary. We adopt the view that tuples denote statements of
predicate logic about database relations. Then, a null value of the
first kind, respectively second kind,, corresponds to an existentially
quantified variable, respectively universally quantified variable. For
instance if $r$ is a database relation without null values and $X$ is
a range declaration for $r$ then the tuple
$(a,\forall,b,\exists)\ismember R$ is intended to mean ``there exists
an $x\ismember X$ such that for all $y\ismember X: (a,y,b,x)\ismember
r$''. We extend basic operations of the well-known relational algebra
to relations with null values. Using formal notions of correctness and
completeness (adapted from predicate logic) we show that our
extensions are meaningful and natural. Furthermore we reexamine the
generalized join within our framework. Finally we investigate the
algebraic structure of the class of relations with null values under a
partial ordering which can be interpreted as a kind of logical
implication." ,
bibdate	=	"Wed Jul 31 21:42:40 1991" ,
owner	=	"curtis" ,
)

@article	( BISKUP83,
key	=	"Biskup" ,
author	=	"Biskup, J." ,
title	=	"{A} {F}oundation {O}f {C}odd's {R}elational {M}aybe-{O}perations" ,
journal	=	tods ,
volume	=	"8" ,
number	=	"4" ,
month	=	dec ,
year	=	"1983" ,
pages	=	"608--636" ,
keywords=	"Relational database; null value; maybe-tuple,
closed world assumption; open world assumption; representation;
information content; redundancy; relational algebra; negative
information" ,
abstract=	"Database relations which possibly contain
maybe-tuples and null values are formally interpreted by our notion of
representation, which uses classical notions of predicate logic,
elaborates Codd's proposal of maybe-tuples, and adopts Reiter's
concept of a closed world. Precise notions of information content and
redundancy, associated with our notion of representation, are
investigated. Extensions of the relational algebra to relations with
maybe-tuples and null values are proposed. Our extensions are
essentially Codd's, with some modifications. It is proved that these
extensions have natural properties which are formally stated as being
adequate and restricted. By the treatment of difference and division,
our formal framework can be used even for operations that require
``negative information.'' Finally, extensions of update operations are
discussed." ,
annote	=	"Biskup summarizes Lipski's work as observing that
besides the two extreme cases in which we know either everything or
nothing about a value, there is also the general case in which we have
partial information on a value-more precisely, in which we know that
the value is an element of some set. Vassiliou also treats another
null value, meaning ``attribute not applicable'' or ``inconsistent''.
Both approaches are seen too impractical due to the high computational
complexity of the query evaluation algorithms. Codd's proposal can be
implemented within the framework of a common relational database
system, without substantially increasing the complexity of the basic
algorithms." ,
bibdate	=	"Fri Feb  8 16:18:31 1985" ,
)

@article	( BISKUP84,
key	=	"Biskup" ,
author	=	"Biskup, J." ,
title	=	"{E}xtending the relational algebra for relations
with maybe tuples and existential and universal null values" ,
journal	=	"Fundamenta Informatic\ae" ,
volume	=	"VII" ,
number	=	"1" ,
year	=	"1984" ,
pages	=	"129--150" ,
keywords=	"do not have article " ,
abstract=	"do not have article " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BOLLOJU90,
key	=	"Bolloju" ,
author	=	"Bolloju, N" ,
title	=	"{M}odelling of {I}mprecise and {U}ncertain {I}nformation" ,
booktitle=	"Proc. Conf. on Management of Data (COMAN '90)" ,
address	=	"New Delhi, India" ,
month	=	dec ,
year	=	"1990" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BORGIDA85A,
key	=	"Borgida" ,
author	=	"Borgida, A." ,
title	=	"{L}anguage features for flexible handling of
exceptions in information systems" ,
year	=	"1985" ,
journal	=	tods ,
volume	=	"10" ,
pages	=	"565--603" ,
number	=	"4" ,
)

@inproceedings	( BORGIDA85B,
key	=	"Borgida \& Williamson" ,
author	=	"Borgida, A. and Williamson, K. E." ,
title	=	"{A}ccommodating exceptions in databases, and
refining the schema by learning from them" ,
year	=	"1985" ,
booktitle=	vldb ,
address	=	"Stockholm" ,
)

@inproceedings	( BORGIDA89,
key	=	"Borgida \& Etherington" ,
author	=	"Borgida, A. and Etherington, D." ,
title	=	"{H}ierarchical {K}nowledge {B}ases and {E}fficient
{D}isjunctive {R}easoning" ,
year	=	"1989" ,
pages	=	"33--43" ,
booktitle=	"Proc. First International Conference on Principles
of Knowledge Representation and Reasoning" ,
address	=	"Toronto" ,
month	=	may ,
)

@article	( BOSC88,
key	=	"Bosc et al." ,
author	=	"Bosc, P. and Galibourg, M. and Hamon, G." ,
title	=	"{F}uzzy {Q}uerying with {SQL}: {E}xtensions and
{I}mplementation {A}spects" ,
journal	=	"Fuzzy Sets \& Systems" ,
volume	=	"28" ,
year	=	"1988" ,
pages	=	"333--349" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BOSC89,
key	=	"Bosc \& Galibourg" ,
author	=	"Bosc, P. and Galibourg, M." ,
title	=	"{I}ndexing principles for a fuzzy data base" ,
journal	=	"Information Sciences" ,
volume	=	"14" ,
number	=	"6" ,
pages	=	"493--???" ,
year	=	"1989" ,
abstract=	" Up to now, many theoretical works about fuzzy
databases have been defined by designing some extension of the
relational model. Our purpose is to discuss some implementation
aspects related to these databases. This point of view does not seem
to be a usual concern of such systems, whereas it is of prime
importance with respect to their future performances. We focus on the
evaluation of a class of queries, called mono-attribute restrictions.
We show how some basic principles can be applied to improve such a
'fuzzy associative' retrieval, by means of an indexing-like access
method. Lastly, some implementation solutions are presented. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BOSC90,
key	=	"Bosc \& Pivert" ,
author	=	"Bosc, P. and Pivert, O." ,
title	=	"{S}ome {A}lgorithms for {E}valuating {F}uzzy {R}elational
{Q}ueries" ,
booktitle=	"Int. Conf. on Information Processing and
Management of Uncertainty in Knowledge-Based Systems" ,
year	=	"1990" ,
pages	=	"431--442" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BOSC91,
key	=	"Bosc \& Pivert" ,
author	=	"Bosc, P. and Pivert, O." ,
title	=	"{A}bout {E}quivalences in {SQL}f, a {R}elational {L}anguage
{S}upporting {I}mprecise {Q}uerying" ,
booktitle=	"Proc. International Fuzzy Engineering Symposium" ,
address	=	"Yokohama, Japan" ,
year	=	"1991" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BOSC92A,
key	=	"Bosc \& Pivert" ,
author	=	"Bosc, P. and Pivert, O." ,
title	=	"{S}ome {P}roperties of {A}lpha-{C}uts of {F}uzzy {P}redicates" ,
booktitle=	"Proc 11th European Meeting on Cybernetics and
Systems Research" ,
address	=	"Vienna, Austria" ,
year	=	"1992" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BOSC92B,
key	=	"Bosc \& Pivert" ,
author	=	"Bosc, P. and Pivert, O." ,
title	=	"{O}n the {E}valuation of {F}uzzy {Q}uantified {Q}ueries in a
{D}atabase {M}anagement {S}ystem" ,
booktitle=	"Proceedings of the North American Fuzzy
Information Society" ,
year	=	"1992" ,
month	=	dec ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BOWERS84,
key	=	"Bowers" ,
author	=	"Bowers, D. S." ,
title	=	"{A} database architecture for aggregate-incomplete
data" ,
year	=	"1984" ,
journal	=	"The Computer Journal" ,
volume	=	"27" ,
number	=	"4" ,
pages	=	"294--300" ,
)

@inproceedings	( BREWKA90,
key	=	"Brewka" ,
author	=	"Brewka, G." ,
title	=	"{H}andling {I}ncomplete {K}nowledge in {A}rtificial
{I}ntelligence" ,
booktitle=	"Information Systems and Artificial Intelligence:
Integration Aspects" ,
address	=	"Berlin" ,
editor	=	"Kargiannis, D." ,
month	=	"Mar" ,
year	=	"1990" ,
pages	=	"11--29" ,
abstract=	"In this paper we first discuss the important role
of nonmonotonic reasoning for Artificial Intelligence. After
presenting some simple forms of nonmonotonicity as they arise in
various well-known AI systems we present in Section 2 some of the most
important existing nonmonotonic logics: McCarthy's circumscription,
Moore's autoepistemic logic, and Reiter's default logic. Section 3
examines an approach in which default reasoning is reduced to
reasoning in the presence of inconsistent information. The approach is
based on the notion of preferred maximal consistent subsets. It is
shown that these preferred subsets can be defined in such a way that
it is possibly (sic) to represent priorities between defaults
adequately. Section 4 briefly discusses the problem of implementing
nonmonotonic systems." ,
bibdate	=	"Sun Apr  7 17:11:20 1991" ,
owner	=	"curtis" ,
)

@techreport	( BROWN90,
key	=	"Brown \& Markert" ,
author	=	"Brown, D. E. and Markert, W. J." ,
title	=	"{U}ncertainty {M}anagement with {I}mprecise {K}nowledge
with {A}pplication to {D}esign" ,
type	=	"IPC-TR-" ,
number	=	"90-001" ,
institution=	"University of Virginia" ,
year	=	"1990" ,
month	=	jan ,
abstract=	"Uncertainty management is critical to the
effective use of knowledge-based systems in a wide variety of domains.
Design is typical of these domains in that the implementation of a
design in an artifact, the future environment for the artifact, and
the component characteristics of the artifact are all uncertain.
Existing probabilistic schemes to address the inherent uncertainty in
areas like design assume precise knowledge of the probabilities of
relevant events. This paper defines a probabilistic method for
uncertainty management with imprecise inputs. The approach combines
Bayesian inference networks and information theoretic inference
procedures. The resulting scheme manages both imprecision and
uncertainty in the problem domain. An application of the approach to
material design is described." ,
bibdate	=	"Wed Apr  1 15:20:41 1992" ,
owner	=	"curtis" ,
)

@article	( BRUDNO88,
key	=	"Brudno" ,
author	=	"Brudno, V. A." ,
title	=	"{E}stimating the unknown values in a database with
incomplete information" ,
journal	=	"Automation and Remote Control" ,
volume	=	"49" ,
number	=	"1" ,
month	=	jan ,
year	=	"1988" ,
pages	=	"114--119" ,
abstract=	"do not have article TJ 212 A73" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BRUDNO89,
key	=	"Brudno" ,
author	=	"Brudno, V. A." ,
title	=	"{V}aluations in {I}ncomplete {I}nformation {D}atabases" ,
journal	=	"Information Sciences" ,
volume	=	"47" ,
year	=	"1989" ,
pages	=	"389--398" ,
abstract=	"Two types of valuations for a query expression in
a relational database with incomplete tuples (values of some
attributes missing) are presented. Valuations are computed at the
intentional level as consequences of given integrity constraints." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BUCKLES82,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{A} fuzzy representation of data for relational
databases" ,
journal	=	"Fuzzy Sets and Systems" ,
volume	=	"7" ,
number	=	"3" ,
month	=	may ,
year	=	"1982" ,
pages	=	"213--226" ,
keywords=	"do not have article " ,
abstract=	"do not have article " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( BUCKLES82A,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{F}uzzy databases and their applications" ,
booktitle=	"Fuzzy Information and Decision Processes" ,
editor	=	"M.M. Gupta and E. Sanchez" ,
publisher=	"North-Holland" ,
address	=	"Amsterdam" ,
year	=	"1982" ,
pages	=	"361--371" ,
abstract=	"do not have article " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BUCKLES82B,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{S}ecurity and {F}uzzy {D}atabases" ,
booktitle=	"IEEE 1982 Proc. of the Int. Conf. on Cybernetics
and Society" ,
year	=	"1982" ,
pages	=	"213--226" ,
abstract=	"do not have " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BUCKLES83,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{I}nformation {T}heoretical {C}haracterization of {F}uzzy
{R}elational {D}atabases" ,
journal	=	"IEEE Transactions on Systems, Man and Cybernetics" ,
volume	=	"SMC-13" ,
number	=	"1" ,
year	=	"1983" ,
pages	=	"74--77" ,
abstract=	"A fuzzy relational database is a medium capable of
representing information that is inherently imprecise or is the
aggregation of the subjective opinions of a number of individuals.
Measuring the degree of precision or lack thereof is important for two
reasons. First, if the measures themselves achieve extrema when
conditions match what is intuitively recognized as maximum and minimum
fuzziness, then confidence in the medium to faithfully represent the
intervening range of precision is increased. Second, querying fuzzy
information may result in ambiguous replies and measures of
preciseness may fathom how well the query discriminated among the
possible replies. Entropy measures based on the fuzzy and
probabilistic attributes of databases are devloped as applied to the
two ends mentioned above." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BUCKLES83A,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{E}xtension of the fuzzy database with fuzzy
arithmetic" ,
booktitle=	"Proceedings of the IFAC Symposium, Fuzzy
Information, Knowledge Representation and Decision Processes" ,
address	=	"Marseille, France" ,
month	=	jul ,
year	=	"1983" ,
pages	=	"409--414" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BUCKLES83B,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{Q}uery {L}anguages for {F}uzzy {D}atabases" ,
booktitle=	"Management Decision Support Systems" ,
year	=	"1983" ,
pages	=	"241--252" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BUCKLES84,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{E}xtending the fuzzy database with fuzzy numbers" ,
journal	=	"Information Science" ,
number	=	"34" ,
year	=	"1984" ,
pages	=	"145--155" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BUCKLES85,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{U}ncertainty {M}odels in {I}nformation and {D}atabase
{S}ystems" ,
journal	=	"Information Sciences" ,
volume	=	"11" ,
year	=	"1985" ,
pages	=	"77--87" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BUCKLES86,
key	=	"Buckles et al." ,
author	=	"Buckles, B. P. and Petry, F. E. and Sachar, H." ,
title	=	"{R}etrieval and {D}esign {C}oncepts for {S}imilarity-based
({F}uzzy) {R}elational {D}atabases" ,
booktitle=	"Robotics and Expert Systems - 1986, Proceedings of
ROBEXS'86: The Second Annual Workshop on Robotics and Expert Systems" ,
address	=	"Houston, TX" ,
month	=	jun ,
year	=	"1986" ,
pages	=	"335--343" ,
abstract=	"The central idea of similarity-based databases is
that equivalence or identity relationships among attribute values are
replaced with a measure of ``nearness'', the similarity relationship.
Because separate attribute values are thus not semantically distinct
entities, the functional dependencies between attributes must reflect
the similarity between key attributes values. Matching operations
between query terms and attribute values is inexact. The truth value
of a match also uses the similarity relationship as a basis." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( BUCKLES87,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{G}eneralized {D}atabase and {I}nformation {S}ystems" ,
booktitle=	"Analysis of Fuzzy Information" ,
year	=	"1987" ,
pages	=	"177--201" ,
volume	=	"2" ,
abstract=	"do not have article " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BUCKLES91,
key	=	"Buckles \& Petry" ,
author	=	"Buckles, B. P. and Petry, F. E." ,
title	=	"{T}owards a {F}uzzy {O}bject-{O}riented {D}ata {M}odel" ,
booktitle=	"Proceedings of NAFIPS, the North American Fuzzy
Info. Proc. Society `91" ,
month	=	may ,
year	=	"1991" ,
pages	=	"73--77" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BUNEMAN87,
key	=	"Buneman et al." ,
author	=	"Buneman, P. and Davidson, S. B. and Watters, A." ,
title	=	"{Q}uerying {I}ndependent {D}atabases" ,
journal	=	"Information Sciences" ,
volume	=	"43" ,
number	=	"1" ,
month	=	aug ,
year	=	"1987" ,
pages	=	"170--218" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( BUNEMAN88,
key	=	"Buneman et al." ,
author	=	"Buneman, P. and Davidson, S. B. and Watters, A." ,
title	=	"{A} {S}emantics for {C}omplex {O}bjects and {A}pproximate
{Q}ueries" ,
booktitle=	pods ,
address	=	"Austin, TX" ,
month	=	"March" ,
year	=	"1988" ,
pages	=	"305--314" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( BUNEMAN90,
key	=	"Buneman et al." ,
author	=	"Buneman, P. and Davidson, S. B. and Watters, A." ,
title	=	"{A} {S}emantics for {C}omplex {O}bjects and {A}pproximate
{A}nswers" ,
journal	=	"Journal of Computer and System Sciences" ,
month	=	aug ,
year	=	"1990" ,
pages	=	"170--218" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( CASEAU91,
key	=	"Caseau" ,
author	=	"Caseau, Y." ,
title	=	"{C}onstraints in an {O}bject-{O}riented {D}eductive
{D}atabase" ,
booktitle=	"Proc. of the Int. Conf. on Deductive and
Object-Oriented Databases (DOOD'91)" ,
address	=	"Munich, Germany" ,
month	=	dec ,
year	=	"1991" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( CAVALLO87,
key	=	"Cavallo \& Pittarelli" ,
author	=	"Cavallo, R. and Pittarelli, M." ,
title	=	"{T}he {T}heory of {P}robabilistic {D}atabases" ,
booktitle=	vldb ,
address	=	"Brighton, England" ,
editor	=	"Hammersley, P." ,
month	=	sep ,
year	=	"1987" ,
pages	=	"71--81" ,
abstract=	"A theory of probabilistic databases is outlined.
This theory is one component of an integrated approach to
data-modelling that accommodates both probabilistic and relational
data. In fact, many of the results presented here were developed in
the context of a framework for structural modelling of systems. Much
that is fundamental to relational database theory was also developed
in this context, and previous to the introduction by Codd of the
relational model of data. Probabilistic databases can store types of
information that cannot be represented using the relational model.
Probabilistic databases may also be viewed as generalizations of
relational databases; any relational database can be represented
without loss of information by a probabilistic database. A number of
relational database concepts are shown to have probabilistic
counterparts. In many cases, it is preferable to deal with the
probabilistic formulation of a concept even when applying it to a
relational database. For example, we define a new project-join mapping
for relational databases that is based on transforming a relational to
a probabilistic database. This mapping is shown to have more fixed
points than the standard one." ,
bibdate	=	"Sun Apr  7 17:11:20 1991" ,
owner	=	"curtis" ,
)

@article	( CHAN93,
key	=	"Chan" ,
author	=	"Chan, E." ,
title	=	"{A} {P}ossible {W}orld {S}emantics for {D}isjunctive
{D}atabases" ,
journal	=	tkde ,
volume	=	"5" ,
number	=	"2" ,
month	=	apr ,
year	=	"1993" ,
pages	=	"282--292" ,
abstract=	"We investigate the fundamental problem of when a
ground atom in a disjunctive database is assumed false. There are
basically two different approaches for inferring negative information
for disjunctive databases; they are Minker's Generalized Closed World
Assumption (GCWA) and Ross and Topor's Disjunctive Database Rule
(DDR). A problem with the GCWA is that disjunctive clauses are
sometimes interpreted exclusively, even when they are intended for
inclusive interpretation. On the other hand, the DDR always interprets
disjunctive clauses inclusively. We argue that neither approach is
satisfactory. Whether a disjunctive clause is interpreted exclusively
or inclusively should be specified explicitly. Negative information
should then be inferred according to the stated intent of the
disjunctive clauses. A database semantics called PWS is proposed to
solve the aforementioned problem. We also show that for propositional
databases with no negative clauses, the problem of determining if a
negative ground literal is inferred under the GCWA is co-NP-hard,
while the same problem can be solved efficiently under the DDR and
PWS. However, in the general case, the problem becomes co-NP-complete
for the DDR and PWS. Relationships among GCWA, DDR, and PWS are
highlighted. In general, disjunctive clauses are interpreted
inclusively under the DDR and unpredictably under the GCWA. We also
characterize when the GCWA interprets disjunctive clauses exclusively.
Throughout this paper, we assume that both the head and the body of a
clause consists of atoms only." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( CHANDRASEKARAN82,
key	=	"Chandrasekaran et al." ,
author	=	"Chandrasekaran, B. and Mittal, S. and Smith, J. W." ,
title	=	"{R}easoning with {U}ncertain {K}nowledge: {T}he {MDX}
{A}pproach" ,
booktitle=	"AMIA Congress 82" ,
publisher=	"Masson Publishing" ,
address	=	"NY" ,
editor	=	"Lindberg, D.A.B. et al." ,
year	=	"1982" ,
pages	=	"335--339" ,
abstract=	"Traditional approaches to handling uncertainty
inherent in medical knowledge and data have tried to reduce all kinds
of uncertainty to a single scale, manipulated by global rules of
combination. This paper presents an alternate scheme, as implemented
in the MDX diagnosis system. This scheme is based on two key ideas. 1)
Uncertainty in medical data is handled by a database system with
strategies that can be specialized for this purpose. 2) In the
diagnostic structure, each hypothesis is assigned one of a small
number of states of uncertainty, which is computed by a multilayered
abstraction hierarchy. Each layer of the hierarchy combines the
constituent pieces of evidence to form a symbolic uncertainty measure
for the next higher level." ,
bibdate	=	"Thu Jan 15 15:37:14 1987" ,
owner	=	"manning" ,
)

@article	( CHANG78,
key	=	"Chang \& Ke" ,
author	=	"Chang, S. K. and Ke, J. S." ,
title	=	"{D}atabase {S}keleton and its {A}pplication to {F}uzzy
{Q}uery {T}ranslation" ,
journal	=	tse ,
volume	=	"SE-4" ,
year	=	"1978" ,
pages	=	"31--43" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( CHANG79,
key	=	"Chang \& Ke" ,
author	=	"Chang, S. K. and Ke, J. S." ,
title	=	"{T}ranslation of fuzzy queries for relational
database systems" ,
journal	=	"IEEE Transactions on Pattern Analysis and Machine
Intelligence (PAMI-1)" ,
year	=	"1979" ,
pages	=	"281--294" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( CHISHOLM87,
key	=	"Chisholm et al." ,
author	=	"Chisholm, P. and Chen, G. and Ferbrache, D. and
Thanisch, P. and Williams, M. H." ,
title	=	"{C}oping with indefinite and negative data in
deductive databases: {A} survey" ,
journal	=	"Data \& Knowledge Engineering" ,
volume	=	"2" ,
year	=	"1987" ,
pages	=	"259--284" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( CHUNG90,
key	=	"Chung et al." ,
author	=	"Chung, Jen-Yao and Jane W. S. Liu and Kwei-Jay Lin" ,
title	=	"{S}cheduling {P}eriodic {J}obs {T}hat {A}llow {I}mprecise
{R}esults" ,
journal	=	"IEEE Transactions on Computers" ,
volume	=	"39" ,
number	=	"9" ,
month	=	sep ,
year	=	"1990" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( CIACCIA89,
key	=	"Ciaccia \& Scalas" ,
author	=	"Ciaccia, P. and Scalas, M." ,
title	=	"{O}ptimization {S}trategies for {R}elational {D}isjunctive
{Q}ueries" ,
journal	=	tse ,
volume	=	"15" ,
number	=	"10" ,
month	=	oct ,
year	=	"1989" ,
pages	=	"1217--1235" ,
keywords=	"disjunctive expressions; join algorithms; query
models; query optimization; relational databases" ,
abstract=	"The main purpose of this work is to extend the
processing capabilities of the optimizer of a relational DBMS in order
to effectively include the treatment of disjunctive queries. To this
aim two new strategies are presented, whose main features are based on
the application of splitting techniques during the execution of the
join operations. Their effectiveness is first shown by means of an
example; then some comparisons with standard procedures are made,
showing promising results. The inclusion of these techniques in the
relational query processing environment requires a broader view of the
evaluation phase, where more than one expression can now be present. A
heuristic algorithm for the reduction of the number of candidate
relational expressions is also proposed." ,
bibdate	=	"Fri Oct  6 11:10:31 1989" ,
owner	=	"robyn" ,
)

@article	( CODD79A,
key	=	"Codd" ,
author	=	"Codd, E. F." ,
title	=	"{E}xtending the {D}atabase {R}elational {M}odel to {C}apture
{M}ore {M}eaning" ,
journal	=	tods ,
month	=	dec ,
year	=	"1979" ,
pages	=	"397--434" ,
volume	=	"4" ,
number	=	"4" ,
bibdate	=	"Wed Dec 29 16:55:51 1982" ,
keywords=	"relation, relational database, relational model,
relational schema, database, data model, database schema, data
semantics, semantic model, knowledge representation, knowledge base,
conceptual model, conceptual schema, entity model" ,
abstract=	"During the last three or four years several
investigators have been exploring 'semantic models' for formatted
databases. The intent is to capture (in a more or less formal way)
more of the meaning of the data so that database design can become
more systematic and the database system itself can behave more
intelligently. Two major thrusts are clear: (1) the search for
meaningful units that are as small as possible - atomic semantics; (2)
the search for meaningful units that are larger than the usual n-ary
relation - molecular semantics. In this paper we propose extensions to
the relational model to support certain atomic and molecular
semantics. These extensions represent a synthesis of many ideas from
the published work in semantic modeling plus the introduction of new
rules for insertion, update, and deletion, as well as new algebraic
operators." ,
)

@article	( CODD86B,
key	=	"Codd" ,
author	=	"Codd, E. F." ,
title	=	"{M}issing {I}nformation ({A}pplicable and {I}napplicable)
in {R}elational {D}atabases" ,
journal	=	sigmod ,
publisher=	"ACM" ,
volume	=	"15" ,
number	=	"4" ,
month	=	dec ,
year	=	"1986" ,
pages	=	"53--78" ,
abstract=	"There has been some technical and justified
criticism of the treatment of missing information in the data
sublanguage SQL and in IBM's Database 2 system (a relational database
management system). Some of this criticism has been directed (by
mistake) at the relational model. The purpose of this paper is to
clarify and extend the treatment of missing information by the
relational model. The clarification places heavy emphasis on the
semantic aspects of missing information. The extension, which is
relatively minor, provides a systematic approach (independent of data
type) to dealing with the inapplicability of certain properties to
some objects. This This extension does not invalidate any part of the
present version of the relational model." ,
bibdate	=	"Tue Jan  6 17:24:31 1987" ,
owner	=	"manning" ,
)

@article	( CODD87,
key	=	"Codd" ,
author	=	"Codd, E. F." ,
title	=	"{M}ore {C}ommentary on {M}issing {I}nformation in
{R}elational {D}atabases ({A}pplicable and {I}napplicable {I}nformation)" ,
journal	=	sigmod ,
publisher=	acm ,
volume	=	"16" ,
number	=	"1" ,
month	=	mar ,
year	=	"1987" ,
pages	=	"42--50" ,
abstract=	"My earlier paper TRI/EFC-4 from The Relational
Institute on this subject was published in ACM SIGMOD Record,
December, 1986. As a result, I have received several comments and
proposed changes. The purpose of this paper is to respond to these
items, while continuing to place heavy emphasis on the semantic
aspects of missing information. The response is principally further
explanation, but a few changes of a quite minor character are
proposed. In this paper, the reader is assumed to have read TRI/EFC-4." ,
bibdate	=	"Wed May  6 17:58:23 1987" ,
owner	=	"manning" ,
)

@inbook		( CODD90A,
key	=	"Codd" ,
author	=	"Codd, E. F." ,
title	=	"{M}issing {I}nformation" ,
booktitle=	"The Relational Model for Database Management:
Version 2" ,
chapter	=	"8--9" ,
pages   =       "169--206" ,
abstract=	"do not have article" ,
publisher=	"Addison-Wesley Publishing Company, Inc." ,
year	=	"1990" ,
)

@inproceedings	( CROSS91,
key	=	"Cross \& Sudkamp" ,
author	=	"Cross, V. and Sudkamp, T." ,
title	=	"{R}epresentation and support generation in fuzzy
relational databases" ,
booktitle=	"Proceedings of the IEEE 1991 National Aerospace
and Electronics Conference - NAECON 1991" ,
address	=	"Dayton, OH" ,
month	=	may ,
year	=	"1991" ,
pages	=	"1136--1143" ,
abstract=	" It is pointed out that standard relational
database management systems are incapable of representing and
manipulating the imprecise, incomplete, and vague information that is
typically encountered in complex problem domains. Fuzzy relational
databases have been developed to increase the flexibility in the
representation of domain information. The different models of fuzzy
relations and their roles in the framework of fuzzy relational
database management systems are reviewed. The applicability of fuzzy
relational database techniques as a methodology for approximate
reasoning is examined. Many similarities exist in the processes that
are used for fuzzy relational operations and those of approximate
reasoning; however, the goals are often different. In fuzzy relational
database theory, the objective is measuring similarity. For
approximate reasoning, the objective is determining maximal
compatibility. Several classes of similarity measures are examined to
determine their appropriateness as compatibility measures in
approximate reasoning. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DANFORTH92A,
key	=	"Danforth \& Valduriez" ,
author	=	"Danforth, S. and Valduriez, P." ,
title	=	"{T}he data model of {FAD}: a database programming
language" ,
journal	=	"Information Sciences" ,
volume	=	"60" ,
number	=	"1992" ,
pages	=	"51--75" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DATE82,
key	=	"Date" ,
author	=	"Date, C. J." ,
title	=	"{N}ull {V}alues in {D}atabase {M}anagement" ,
booktitle=	"Proceedings of the 2nd British National Conference
on Databases" ,
address	=	"Bristol, England" ,
month	=	jul ,
year	=	"1982" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inbook		( DATE86D,
key	=	"Date" ,
author	=	"Date, C. J." ,
title	=	"{N}ull {V}alues in {D}atabase {M}anagement" ,
booktitle=	"Relational Database: Selected Writings" ,
publisher=	"Addison-Wesley" ,
address	=	"Reading, MA" ,
year	=	"1986" ,
chapter	=	"15" ,
pages	=	"313--334" ,
abstract=	"We examine the question of null values in a
database system. We begin by defining the term ``null value'' and
outlining the problems that null values are intended to solve. We go
on to discuss the properties of null values in detail, and describe
some extensions to the relational model for dealing with such values.
We then discuss some of the difficulties that occur in connexion with
the null value concept. It is our opinion that the problem is
generally not well understood, and that any attempt to incorporate
support for null values into an implemented system should be
considered premature at this time. We sketch an alternative approach
based on the concept of default values." ,
bibdate	=	"Thu Sep  3 10:03:47 1987" ,
owner	=	"manning" ,
)

@inbook		( DATE86K,
key	=	"Date" ,
author	=	"Date, C. J." ,
title	=	"{NOT} is {N}ot `{N}ot'! (notes on three-valued logic and
related matters)" ,
booktitle=	"Relational Database Writings 1985 - 1989" ,
publisher=	"Addison-Wesley" ,
address	=	"Reading, MA" ,
year	=	"1989" ,
chapter	=	"8" ,
pages	=	"217--248" ,
abstract=	"do not have" ,
bibdate	=	"Thu Sep  3 10:03:47 1987" ,
owner	=	"curtis" ,
)

@inbook		( DATE86L,
key	=	"Date" ,
author	=	"Date, C. J." ,
title	=	"{EXISTS} is {N}ot `{E}xists'! (some logical flaws in
{SQL})" ,
booktitle=	"Relational Database Writings 1985 - 1989" ,
publisher=	"Addison-Wesley" ,
address	=	"Reading, MA" ,
year	=	"1989" ,
chapter	=	"13" ,
pages	=	"339--356" ,
abstract=	"do not have" ,
bibdate	=	"Thu Sep  3 10:03:47 1987" ,
owner	=	"curtis" ,
)

@article	( DATRI89,
key	=	"D'Atri \& Tarantino" ,
author	=	"D'Atri, A. and Tarantino, L." ,
title	=	"{F}rom {B}rowsing to {Q}uerying" ,
journal	=	"IEEE Database Engineering Bulletin - Special Issue
on Imprecision in Databases" ,
volume	=	"12" ,
number	=	"2" ,
month	=	jun ,
year	=	"1989" ,
pages	=	"46--53" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( DAYON90,
key	=	"Dayon" ,
author	=	"Dayon, B." ,
title	=	"{R}eliability of {A}nswers to an {SQL} {Q}uery" ,
type	=	"TR" ,
institution=	"Department of Computer Sciences, Concordia
University" ,
year	=	"1990" ,
month	=	may ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DEAN88A,
key	=	"Dean \& Boddy" ,
author	=	"Dean, T. and Boddy, M." ,
title	=	"{R}easoning {A}bout {P}artially {O}rdered {E}vents" ,
journal	=	"Artificial Intelligence" ,
volume	=	"36" ,
number	=	"3" ,
month	=	oct ,
year	=	"1988" ,
pages	=	"375--399" ,
abstract=	" This paper describes a class of temporal
reasoning problems involving events whose order is not completely
known. We examine the complexity of such problems and show that for
all but trivial cases these problems are likely to be intractable. As
an alternative to a complete, but potentially exponential-time
decision procedure, we provide a partial decision procedure that
reports useful results and runs in polynomial time. (Author abstract).
" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DEMICHIEL89,
key	=	"Demichiel" ,
author	=	"Demichiel, L. G." ,
title	=	"{R}esolving {D}atabase {I}ncompatibility: {A}n {A}pproach to
{P}erforming {R}elational {O}perations over {M}ismatched {D}omains" ,
journal	=	tkde ,
volume	=	"1" ,
number	=	"4" ,
month	=	dec ,
year	=	"1989" ,
pages	=	"485--493" ,
abstract=	"We present a solution to the problem of supporting
relational database operations despite domain mismatch. Mismatched
domains occur when information must be obtained from databases that
were developed independently. We resolve domain differences by mapping
conflicting attributes to common domains by means of a mechanism of
virtual attributes and then apply a set of extended relational
operations to the resulting values. When one-one mappings cannot be
established between domains, the values that result from attribute
mappings may be partial. We define a set of extended relational
operators that formalize operations over partial values and thus
manipulate the incomplete information that results from resolving
domain mismatch." ,
bibdate	=	"Mon Feb 25 08:50:27 1991" ,
owner	=	"robyn" ,
)

@phdthesis	( DEMICHIEL89A,
key	=	"Demichiel" ,
author	=	"Demichiel, L. G." ,
title	=	"{P}erforming {D}atabase {O}perations over {M}ismatched
{D}omains" ,
year	=	"1989" ,
school	=	"Department of Computer Sciences, Stanford
University" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DEMOLOMBE85,
key	=	"Demolombe \& Fari\~{n}as" ,
author	=	"Demolombe, R. and Fari\~{n}as del Cerro, L." ,
title	=	"{E}fficient {R}epresentation of {I}ncomplete {I}nformation
{A}bout {S}tructured {O}bjects" ,
booktitle=	"Proc. of the Workshop on Knowledge Base Management
Systems " ,
address	=	"Crete" ,
month	=	jun ,
year	=	"1985" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DEMOLOMBE88,
key	=	"Demolombe \& Fari\~{n}as" ,
author	=	"Demolombe, R. and Fari\~{n}as del Cerro, L." ,
title	=	"{A}n {A}lgebraic {E}valuation {M}ethod for {D}eduction in
{I}ncomplete {D}atabases" ,
journal	=	"The Journal of Logic Programming" ,
volume	=	"5" ,
number	=	"3" ,
month	=	sep ,
year	=	"1988" ,
pages	=	"183--205" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DEMOLOMBE91,
key	=	"Demolombe" ,
author	=	"Demolombe, R." ,
title	=	"{A}n {E}fficient {S}trategy for non-{{H}}orn {D}eductive
{D}atabases" ,
year	=	"1991" ,
journal	=	"Theoretical Computer Sciences" ,
volume	=	"78" ,
pages	=	"245--259" ,
number	=	"1" ,
month	=	jan ,
)

@techreport	( DESHPANDE87,
key	=	"Deshpande \& Larson" ,
author	=	"Deshpande and Larson" ,
title	=	"{A}n {A}lgebra for {N}ested {R}elations with support for
nulls and aggregates" ,
type	=	"Research Report" ,
number	=	"CS-91-16" ,
institution=	"University of Waterloo, Canada" ,
year	=	"1987" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DICESARE90,
key	=	"DiCesare \& Sahnoun" ,
author	=	"DiCesare, F. and Sahnoun, Z." ,
title	=	"{L}inguistic {S}ummarization of {F}uzzy {D}ata" ,
journal	=	"Information Services" ,
volume	=	"52" ,
year	=	"1990" ,
pages	=	"141--152" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DIGNUM92,
key	=	"Dignum \& Riet" ,
author	=	"Dignum, F. and van de Riet, R. P." ,
title	=	"{A}ddition and removal of information for a
knowledge base with incomplete information" ,
journal	=	"Data \& Knowledge Engineering" ,
volume	=	"8" ,
year	=	"1992" ,
pages	=	"293--307" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DOCKERY89,
key	=	"Dockery \& Murray" ,
author	=	"Dockery, J. T. and Murray, E." ,
title	=	"{F}uzzy linguistic data bases. {A}n application." ,
journal	=	"Information Sciences" ,
volume	=	"14" ,
number	=	"6" ,
pages	=	"???--???" ,
year	=	"1989" ,
abstract=	" This paper discusses the empirical development
and use of a fuzzy linguistic data base which is relational in
character. Unlike conventional fuzzy searches for crisp data, we
search a data base for fuzzy information. The data base supports
another code which does fuzzy aggregation of data. It has been applied
to support decision making connected with the construction of military
budgets for command, control and communications (C3). " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@phdthesis	( DREIZEN83,
key	=	"Dreizen" ,
author	=	"Dreizen, H. M." ,
title	=	"{I}mprecise {D}atabase: {R}epresentation of {I}mprecise
and {E}xceptional {C}onditions via {E}mbedded {R}elations" ,
school	=	"University of Illinois" ,
address	=	"Chicago, IL" ,
year	=	"1983" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DREIZEN85,
key	=	"Dreizen \& Chang" ,
author	=	"Dreizen, H. M. and Chang, S. K." ,
title	=	"{I}mprecise {D}atabase: {I}mprecise {Q}ueries and {V}iew
{N}avigation" ,
journal	=	"Inf. Sci. Eng. 1" ,
volume	=	"1" ,
month	=	jan ,
year	=	"1985" ,
pages	=	"12--43" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DREIZEN89,
key	=	"Dreizen \& Chang" ,
author	=	"Dreizen, H. M. and Chang, S. K." ,
title	=	"{I}mprecise {S}chema: {A} {R}ationale for {R}elations with
{E}mbedded {S}ubrelations" ,
journal	=	tods ,
volume	=	"14" ,
number	=	"4" ,
month	=	dec ,
year	=	"1989" ,
pages	=	"447--479" ,
keywords=	"embedded subrelations; exceptional conditions;
imprecise schema; non-1NF; null values" ,
abstract=	"Exceptional conditions are anomalous data which
meet the intent of a schema but not the schema definition, represent a
small proportion of the database extension, and may become known only
after the schema is in use. Admission of exceptional conditions is
argued to suggest a representation that locally stretches the schema
definition by use of relations with embedded subrelations. Attempted
normalization of these relations to 1NF does not yield the static
schema typically associated with such transformations. A class of
relations, termed Exceptional Condition Nested Form (ECNF), is defined
which allows the necessary representation of exceptional conditions
while containing sufficient restrictions to prevent arbitrary and
chaotic inclusion of embedded subrelations. Queries on a subset of
exceptional conditions, the exceptional constraints, are provided an
interpretation via an algorithm that transforms ECNF relations into
1NF relations containing two types of null values. Extensions of
relational algebraic operators, suitable for interactive query
navigation, are defined for use with ECNF relations containing all
forms of exceptional conditions." ,
bibdate	=	"Thu Feb  1 14:11:40 1990" ,
owner	=	"robyn" ,
)

@book		( DUBOIS80,
key	=	"Dubois \& Prade" ,
author	=	"Dubois, D. and Prade, H." ,
title	=	"{F}uzzy {S}ets and {S}ystems: {T}heory and {A}pplications" ,
publisher=	"Academic Press" ,
address	=	"New York, NY" ,
year	=	"1980" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inbook		( DUBOIS88,
key	=	"Dubois et al." ,
author	=	"Dubois, D. and Prade, H. and Testamale, C." ,
title	=	"{H}andling {I}ncomplete or {U}ncertain {D}ata and {V}ague
{Q}ueries in {D}atabase {A}pplications" ,
booktitle=	"Possibility Theory: An Approach to Computerized
Processing of Uncertainty" ,
publisher=	"Plenum Press" ,
address	=	"New York and London" ,
year	=	"1988" ,
chapter	=	"6" ,
pages	=	"217--257" ,
abstract=	"We examine the question of null values in a
database system. We begin by defining the term ``null value'' and
outlining the problems that null values are intended to solve. We go
on to discuss the properties of null values in detail, and describe
some extensions to the relational model for dealing with such values.
We then discuss some of the difficulties that occur in connexion with
the null value concept. It is our opinion that the problem is
generally not well understood, and that any attempt to incorporate
support for null values into an implemented system should be
considered premature at this time. We sketch an alternative approach
based on the concept of default values." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DUBOIS88A,
key	=	"Dubois \& Prade" ,
author	=	"Dubois, D. and Prade, H." ,
title	=	"{I}ncomplete conjunctive information" ,
journal	=	"Computers \& Mathematics with Applications" ,
volume	=	"15" ,
number	=	"10" ,
year	=	"1988" ,
pages	=	"797--810" ,
abstract=	"do not have article QA 76 C5364" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DUBOIS89,
key	=	"Dubois \& Prade" ,
author	=	"Dubois, D. and Prade, H." ,
title	=	"{P}rocessing {F}uzzy {T}emporal {K}nowledge" ,
journal	=	"IEEE Transactions of Systems, Man and Cybernetics" ,
volume	=	"19" ,
number	=	"4" ,
year	=	"1989" ,
pages	=	"729--744" ,
abstract=	"TA 168 I216 BOON" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( DUBOIS90,
key	=	"Dubois \& Prade" ,
author	=	"Dubois, D. and Prade, H." ,
title	=	"{M}easuring properties of fuzzy sets: a general
technique and its use in fuzzy query evaluation." ,
journal	=	"Fuzzy Sets and Systems" ,
volume	=	"38" ,
number	=	"2" ,
year	=	"1990" ,
pages	=	"137--152" ,
abstract=	" Summary: A fuzzy set can be viewed as a
weighted-max combination or as a convex combination of a family of
nested ordinary sets. The latter point of view allows the
interpretation of a fuzzy set as a consonant random set. Then any
numerical set function applied to a fuzzy set leads to a result which
is a random number. The expectation attached to this random number
provides a scalar evaluation of the fuzzy set with respect to the
considered set function. This approach is very general and can be used
for various kinds of measurements: cardinality, confidence measures
attached to the occurrence of events, diameter or perimeter of a fuzzy
region, distance between two sets, etc. Also the fuzziness of the set
to be evaluated naturally induces a fuzzy set of possible evaluations,
and expected values of the lower and upper bounds of this fuzzy set of
numbers can be computed. The weighted max-combination view, which
leads to another type of scalar evaluation, is also briefly discussed.
In this paper the approach above is more particularly applied to the
treatment of queries asking for some global evaluation of a set of
items specified by means of a fuzzy property. This kind of query can
be managed by languages SQL in the case of a crisp set of items. When
this set is fuzzily specified, a scalar answer can still be provided
as well as a fuzzy-valued or interval-valued one if we want to keep
track of the effect of the fuzziness of the query. The case where the
data base contains precise information is considered, as well as the
more general case of fuzzy information data bases. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DUTTA88A,
key	=	"Dutta" ,
author	=	"Dutta, S." ,
title	=	"{A}pproximate spatial reasoning" ,
booktitle=	"Fourth Conference on Artificial Intelligence for
Space Applications" ,
address	=	"Huntsville, AL" ,
month	=	nov ,
year	=	"1988" ,
pages	=	"95--106" ,
abstract=	" We present a model for approximate spatial
reasoning using fuzzy logic to represent the imprecision in the
environment. We develop algorithms to reason from approximate spatial
information such as: A is about 5 miles away and is coming towards me
quite fast. B is quite near C, but is far north of D. B is moving much
faster than C. The kind of spatial information dealt with has two
notable characteristics: it is approximate and may be incomplete. We
present algorithms for determining approximate relative positions of
objects, in both static and dynamic domains. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DUTTA88B,
key	=	"Dutta" ,
author	=	"Dutta, S." ,
title	=	"{A}n {E}vent-based {F}uzzy {T}emporal {L}ogic" ,
booktitle=	"Proc. 18th IEEE Intl. Symp. on Multiple-Valued
Logic" ,
address	=	"Palma de Mallorca, Spain" ,
year	=	"1988" ,
pages	=	"64--71" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DUTTA89,
key	=	"Dutta" ,
author	=	"Dutta, S." ,
title	=	"{G}eneralized {E}vents in {T}emporal {D}atabases" ,
booktitle=	"Proceedings of the Fifth International Conference
on Data Engineering" ,
address	=	"Los Angeles, CA" ,
month	=	feb ,
year	=	"1989" ,
pages	=	"118--126" ,
abstract=	"The concept of time plays a central role in our
lives. Thus it comes as no surprise that the effective representation
and manipulation of temporal data is currently an active area of
research in databases. In this paper, we distinguish between the
concepts of temporal entities and temporal events and extend the
conventional crisp notion of events to define generalized events. We
also note that there are two broad categories of temporal operators,
those which operate on temporal entities and those which operate on
temporal events. We provide new definitions for temporal operators
used for generalized events. We choose a temporal data model which is
independent of conventional data models, but is similar to temporal
data models proposed by other researchers and is sufficiently general
to be applied to suitable extensions of conventional data models. We
show how to combine different generalized events and apply temporal
operators to such compound events. An outline of a possible
implementation of our ideas in the relational data model is also
provided." ,
bibdate	=	"Fri Jan 12 09:59:23 1990" ,
owner	=	"robyn" ,
)

@phdthesis	( DUTTA90,
key	=	"Dutta" ,
author	=	"Dutta, S." ,
title	=	"{A}pproximate {R}easoning with {T}emporal and {S}patial
{C}oncepts" ,
school	=	"University of California, Berkeley" ,
address	=	"Berkeley, CA" ,
month	=	may ,
year	=	"1990" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( DYRESON91A,
key	=	"Dyreson \& Snodgrass" ,
author	=	"Dyreson, C. E. and Snodgrass, R. T." ,
title	=	"{T}emporal {I}ndeterminacy" ,
type	=	"Technical Report" ,
number	=	"TR 91-30" ,
institution=	uazcsd ,
year	=	"1991" ,
month	=	"Dec." ,
pages	=	"31" ,
abstract=	"In temporal indeterminacy, it is known that an
event stored in a temporal database did in fact occur, but it is not
known exactly when the event occurred. We present the possible tuples
data model, in which each indeterminate event is represented with an
interval that delimits when the event might have occurred, and a
probability distribution over that interval. We extend the TQuel query
language with constructs that specify the user's confidence in the
underlying temporal data and in the relationships among that data. We
provide a formal tuple calculus semantics, and show that this
semantics reduces to the determinate semantics. We outline an
efficient representation of temporal indeterminacy, and efficient
query processing algorithms, demonstrating the practicality of our
proposed approach." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( DYRESON92A,
key	=	"Dyreson et al." ,
author	=	"Dyreson, C. E. and Snodgrass, R. T. and Jensen, C.
S." ,
title	=	"{A} {T}axonomy of {I}ncomplete {I}nformation in {D}atabases" ,
type	=	"unpublished" ,
number	=	"" ,
institution=	uazcsd ,
year	=	"1992" ,
month	=	jun ,
abstract=	"none yet" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( DYRESON92B,
key	=	"Dyreson \& Snodgrass" ,
author	=	"Dyreson, C. E. and Snodgrass, R. T." ,
title	=	"{H}istorical {I}ndeterminacy" ,
type	=	"Technical Report" ,
number	=	"TR 91-30a" ,
institution=	uazcsd ,
year	=	"1992" ,
month	=	"Revised Feb." ,
pages	=	"31" ,
abstract=	"In temporal indeterminacy, it is known that an
event stored in a temporal database did in fact occur, but it is not
known exactly when the event occurred. We present the possible tuples
data model, in which each indeterminate event is represented with an
interval that delimits when the event might have occurred, and a
probability distribution over that interval. We extend the TQuel query
language with constructs that specify the user's confidence in the
underlying temporal data and in the relationships among that data. We
provide a formal tuple calculus semantics, and show that this
semantics reduces to the determinate semantics. We outline an
efficient representation of temporal indeterminacy, and efficient
query processing algorithms, demonstrating the practicality of our
proposed approach." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DYRESON93A,
key	=	"Dyreson \& Snodgrass" ,
author	=	"Dyreson, C. E. and Snodgrass, R. T." ,
title	=	"{V}alid-{T}ime {I}ndeterminacy" ,
booktitle=	"Proceedings of the International Conference on
Data Engineering" ,
address	=	"Vienna, Austria" ,
month	=	apr ,
pages	=	"335--343" ,
year	=	"1993" ,
bibdate	=	"Thu Oct 22 10:29:43 1992" ,
owner	=	"rts" ,
)

@techreport	( DYRESON93K,
key	=	"Dyreson \& Snodgrass" ,
author	=	"Dyreson, C. E. and Snodgrass, R. T." ,
title	=	"{S}upporting {V}alid-time {I}ndeterminacy" ,
type	=	"Technical Report" ,
number	=	"TR 93-30" ,
institution=	uazcsd ,
year	=	"1993" ,
month	=	"Nov." ,
pages	=	"52" ,
abstract=	"" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( DYRESON93Z,
key	=	"Dyreson" ,
author	=	"Dyreson, C." ,
title	=	"{A} {B}ibliography on {U}ncertainty {M}anagement in
{I}nformation {S}ystems" ,
booktitle=	"Proceedings of the Workshop on Uncertainty
Management in Information Systems: From Needs to Solutions" ,
address	=	"Avalon, Santa Catalina, California" ,
month	=	apr ,
year	=	"1993" ,
pages	=	"187--220" ,
abstract=	"" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( EASTMAN87,
key	=	"Eastman" ,
author	=	"Eastman, C. M." ,
title	=	"{A}pproaches to {A}pproximate {R}etrieval in {D}atabase
{M}anagement {S}ystems" ,
booktitle=	"NAFIPS 87: Proceedings of the North American Fuzzy
Information Processing Society Workshop" ,
month	=	may ,
year	=	"1987" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( EASTMAN89,
key	=	"Eastman" ,
author	=	"Eastman, C. M." ,
title	=	"{A}pproximate {R}etrieval: {A} {C}omparison of {I}nformation
{R}etrieval and {D}atabase {M}anagement {S}ystems" ,
journal	=	"IEEE Database Engineering Bulletin - Special Issue
on Imprecision in Databases" ,
volume	=	"12" ,
number	=	"2" ,
month	=	jun ,
year	=	"1989" ,
pages	=	"41--45" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( ESCULIER90,
key	=	"Esculier" ,
author	=	"Esculier, C." ,
title	=	"{N}on-{M}onotonic {K}nowledge {E}volution in {VLKDB}s" ,
booktitle=	"Proc. of the 16th Conf. on Very Large Databases
(VLDB'90)" ,
address	=	"Brisbane, Australia" ,
year	=	"1990" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@book		( FLEISCHMAN91,
key	=	"Fleischman" ,
author	=	"Fleischman, R. M." ,
title	=	"{S}upporting {F}uzzy {L}ogic {S}election {P}redicates on a
{H}igh {T}hroughput {D}atabase {S}ystem" ,
publisher=	"MIT Library" ,
address	=	"Boston, MA" ,
year	=	"1991" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( FUHR90,
key	=	"Fuhr" ,
author	=	"Fuhr, N." ,
title	=	"{A} {P}robabilistic {F}ramework for {V}ague {Q}ueries and
{I}mprecise {I}nformation in {D}atabases" ,
booktitle=	vldb ,
address	=	"Brisbane, Australia" ,
year	=	"1990" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( GADIA91A,
key	=	"Gadia et al." ,
author	=	"Gadia, S. K. and Nair, S. and Poon, Y.-C." ,
title	=	"{I}ncomplete {I}nformation in {R}elational {T}emporal
{D}atabases" ,
number	=	"Technical Report" ,
institution=	"Department of Computer Science, Iowa State
University" ,
address	=	"Ames, IA" ,
year	=	"1991" ,
month	=	dec ,
abstract=	"We present a model and an algebra for incomplete
information in temporal databases. The model generalizes our previous
model for a temporal database for complete information. It is shown
that our relational operators produce results that are reliable. We
also show, with some minor exceptions, that if the definitions of the
operators were strengthened to give more information, we may obtain
results that are not reliable. These results and exceptions parallel
Biskup`s findings for relational databases with incomplete
information." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GADIA92A,
key	=	"Gadia et al." ,
author	=	"Gadia, S. K. and Nair, S. and Poon, Y.-C." ,
title	=	"{I}ncomplete {I}nformation in {R}elational {T}emporal
{D}atabases" ,
booktitle=	vldb ,
address	=	"Vancouver, Canada" ,
month	=	aug ,
year	=	"1992" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GALA91,
key	=	"Gala et al." ,
author	=	"Gala, S. and Chawala, D. and Eastman, C." ,
title	=	"{C}ombining {F}uzzy and {N}onfuzzy {A}pproximate {R}etrieval
in a {D}atabase {M}anagement {S}ystem" ,
booktitle=	"NAFIPS 91 Proceedings of the North American Fuzzy
Information Processing Society Workshop" ,
month	=	may ,
year	=	"1991" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( GALLAIRE84,
key	=	"Gallaire et al." ,
author	=	"Gallaire, H. and Minker, J. and Nicolas, J. M." ,
title	=	"{L}ogic and databases: {A} deductive approach" ,
journal	=	"ACM Computing Surveys" ,
volume	=	"16" ,
number	=	"2" ,
month	=	jun ,
year	=	"1984" ,
pages	=	"153--185" ,
keywords=	"Deductive Databases, Indefinite Data, Logic and
Databases, Null Values, Relational Databases" ,
abstract=	"The purpose of this paper is to show that logic
provides a convenient formalism for studying classical database
problems. There are two main parts to the paper, devoted respectively
to conventional databases and deductive databases. In the first part,
we focus on query languages, integrity modeling and maintenance, query
optimization, and data dependencies. The second part deals mainly with
the representation and manipulation of deduced facts and incomplete
information." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( GARCIA-MOLINA88,
key	=	"Garcia-Molina \& Porter" ,
author	=	"Garcia--Molina, H. and Porter, D." ,
title	=	"{S}upporting {P}robabilistic {D}ata in a {R}elational
{S}ystem" ,
type	=	"TR" ,
number	=	"147--88" ,
institution=	"Princeton University" ,
year	=	"1988" ,
month	=	feb ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( GELENBE83A,
key	=	"Gelenbe" ,
author	=	"Gelenbe, E." ,
title	=	"{I}ncomplete representations of information in data
bases" ,
type	=	"Research Report" ,
number	=	"No 9" ,
institution=	"ISEM, Univ. Paris-Sud" ,
year	=	"1983" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GELENBE83B,
key	=	"Gelenbe" ,
author	=	"Gelenbe, E." ,
title	=	"{I}ncomplete {R}epresentation of {I}nformation in
{D}atabases" ,
booktitle=	"ICOD-2 Proceedings of the Second International
Conference on Databases" ,
address	=	"Cambridge, England" ,
month	=	aug ,
year	=	"1983" ,
pages	=	"246--258" ,
abstract=	"do not have article QA76.9.D3 I25 1983" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GELENBE86,
key	=	"Gelenbe \& Hebrail" ,
author	=	"Gelenbe, E. and Hebrail, G." ,
title	=	"{A} {P}robability {M}odel of {U}ncertainty in {D}ata {B}ases" ,
booktitle=	"Proceedings of the International Conference on
Data Engineering" ,
organization=	"IEEE Computer Society" ,
publisher=	"IEEE Computer Society Press" ,
address	=	"Los Angeles, CA" ,
volume	=	"IEEE Computer Society Order Number 655" ,
month	=	feb ,
year	=	"1986" ,
pages	=	"328--333" ,
abstract=	"Uncertainty in the contents of a data base can be
due to several reasons: errors in the data which is entered, changes
in the real data which have not been introduced into the data base in
the form of updates, errors in the data collection process, unreliable
operation of the computer system, don't care conditions which are
purposely left open by the data base designer, etc. The purpose of
this paper is to present a formal model of uncertainty in terms of a
probabilistic representation of the data base, and to evaluate the
effect of this uncertainty on query processing and on the aggregate or
summary information which may suffice in many applications. Our model
leads to precise quantifiable engineering estimates and to theorems on
the robustness of answers to queries as a function of the uncertainty
in the data." ,
bibdate	=	"Wed Jul 16 15:24:20 1986" ,
owner	=	"manning" ,
)

@inproceedings	( GELFOND91,
key	=	"Gelfond et al." ,
author	=	"Gelfond, M. and Lifschitz, V. and Przymusi\'{n}ka,
H. and Truszczy\'{n}ski, M." ,
title	=	"{D}isjunctive {D}efaults" ,
booktitle=	"Proc. of 2nd Int. Conf. Principles of Knowledge
Representation and Reasoning KR'91" ,
address	=	"Cambridge, MA" ,
month	=	apr ,
year	=	"1991" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GEORGE92,
key	=	"George et al." ,
author	=	"George, R. and Yazici, A. and Petry, F. E. and
Buckles, B. P." ,
title	=	"{U}ncertainty {M}odeling in {O}bject-{O}riented
{G}eographical {I}nformation {S}ystems" ,
booktitle=	"Proc. Int. Conf. on Database and Expert Systems
Applications (DEXA'92)" ,
address	=	"Valencia, Spain" ,
year	=	"1992" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( GESSERT90,
key	=	"Gessert" ,
author	=	"Gessert, G. H." ,
title	=	"{F}our {V}alue {L}ogic for {R}elational {D}atabase {S}ystems" ,
journal	=	sigmod ,
volume	=	"19" ,
number	=	"1" ,
year	=	"1990" ,
pages	=	"29--35" ,
bibdate	=	"Sun Apr  7 17:11:20 1991" ,
owner	=	"curtis" ,
abstract=	"This paper proposes a specific four-valued logic
(4VL) as a means of handling missing data in Relational Data Base
Management systems. The proposed 4VL is a minor variant of the
standard 4VL in which the ``least true'' condition is interpreted as
``inapplicable'' rather that ``false''. The use of this 4VL is
defended on the grounds that by defining several additional unary
operators, the 4VL can be rendered intuitively manageable. The
proposed unary operators contribute to the conceptual utility of the
4VL by providing an explicit way for users to relate familiar results
of two-valued logic to analogous results in 4VL." ,
)

@article	( GESSERT91,
key	=	"Gessert" ,
author	=	"Gessert, G. H." ,
title	=	"{H}andling {M}issing {D}ata by {U}sing {S}tored {T}ruth {V}alues" ,
journal	=	sigmod ,
publisher=	"ACM" ,
volume	=	"20" ,
number	=	"3" ,
month	=	sep ,
year	=	"1991" ,
pages	=	"30--42" ,
abstract=	"This paper proposes a method for handling
inapplicable and unknown missing data. The method is based on: (1)
storing default values (instead of null values) in place of missing
data, (2) storing truth values that describe the logical status of the
default values in corresponding fields of corresponding tables. For
valued logic is used so that the logical status of the default data
values can be described as, not just true or false, but also as
inapplicable or unknown. This method, in contrast to the ``hidden
byte'' approach, has two important advantages: (1) Because the logical
status of all data is represented explicitly in tables, all 4-valued
operations can be handled via a 2-valued data manipulation language,
such as SQL. Language extensions for handling missing data (e.g., ``Is
NULL'') are not necessary. (2) Because data fields always contain a
default value (as opposed to a null value or mark), it is possible to
do arithmetic across missing data and to interpret the logical status
of the result by means of logical operations on the corresponding
stored truth values." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GOLDSTEIN81,
key	=	"Goldstein" ,
author	=	"Goldstein, B." ,
title	=	"{C}onstraints on {N}ull {V}alues in {R}elational {D}atabases" ,
booktitle=	vldb ,
address	=	"Cannes, France" ,
month	=	sep ,
year	=	"1981" ,
pages	=	"101--110" ,
abstract=	"If null values are allowed in a database, the
database designer may want to restrict where they occur. Two
constructs are presented for specifying where null values may occur in
a relational database. Several examples demonstrate the use of these
two techniques. The two constructs are shown to be almost equivalent;
a criterion for exact equivalence is given. Under the same criterion,
interesting special cases of both constructs are also shown to be
equivalent." ,
bibdate	=	"Sun Apr  7 17:11:20 1991" ,
owner	=	"curtis" ,
)

@article	( GOLSHANI85,
key	=	"Golshani" ,
author	=	"Golshani, F." ,
title	=	"{G}rowing {C}ertainty {W}ith {N}ull {V}alues" ,
journal	=	"Information Systems" ,
volume	=	"10" ,
number	=	"2" ,
year	=	"1985" ,
pages	=	"289--297" ,
keywords=	"database query language; incomplete information;
many-sorted algebra; many-valued logic; approximation" ,
abstract=	"Non-availability of part of the data is a problem
common to many database systems. We study here some aspects relating
to incomplete information. Obviously, when the information in a
database is not complete the answer to any query is only an
approximation to the true result. The aim is to get a precise
approximation. We regard databases as many-sorted algebras. Based on
the concept of extended algebra we define what it means for an algebra
to approximate another algebra. We then give the following simple
principle for extending query languages to handle missing data:
``Whenever information is added to an incomplete database subsequent
answers to queries must not be contradictory or less informative than
previously.'' We then apply this principle to extend the functional
query language Varqa. Finally, we compare the previously proposed
many-valued logic systems with the system devised based on our
principles." ,
bibdate	=	"Mon Oct 14 11:53:04 1985" ,
)

@book		( GOODMAN85,
key	=	"Goodman \& Nguyen" ,
author	=	"Goodman, I. R. and Nguyen, H. T." ,
title	=	"{U}ncertainty {M}odels for {K}nowledge-{B}ased {S}ystems" ,
publisher=	"North-Holland" ,
address	=	"Amsterdam" ,
year	=	"1985" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GOTTLOB88,
key	=	"Gottlob \& Zicari" ,
author	=	"Gottlob, G. and Zicari, R." ,
title	=	"{C}losed {W}orld {D}atabases {O}pened {T}hrough {N}ull {V}alues" ,
booktitle=	vldb ,
address	=	"Los Angeles, CA" ,
year	=	"1988" ,
pages	=	"50--61" ,
abstract=	"We propose a new approach to the treatment of
null-valued attributes in the relational model. The approach is based
on the new concept of locally-controlled open world database. A
locally-controlled open world database permits the definition of
portions of a traditional closed world database as open-world.
Attributes, part of a relation, or entire relations can be explicitly
defined as ``open'' through the insertion of null-values. Under this
assumption, we consider three different types of null values: the
standard {\em unknown}, {\em does not exist}, and the new one, called
{\em open}. We give a complete formal specification of the semantics
of these null values. We extend the arithmetic and logical operators
to cover nulls and outline how relational operators can be extended
accordingly. This paper describes ongoing work. We state some open
problems to be solved in order to render our approach more
operational." ,
bibdate	=	"Wed Jul 31 21:42:40 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GRAHNE84,
key	=	"Grahne" ,
author	=	"Grahne, G." ,
title	=	"{D}ependency {S}atisfaction in {D}atabases with
{I}ncomplete {I}nformation" ,
booktitle=	vldb ,
address	=	"Singapore" ,
month	=	aug ,
year	=	"1984" ,
pages	=	"37--45" ,
abstract=	"Two of the major problems raised by information
incompleteness in databases are how to evaluate queries and how to
take data dependencies into account. We give a unified solution of
these two intermingled problems for the relational model. Formal
criteria for the correctness of the relational algebra and dependency
satisfaction are presented. We give a correct definition of the
complete relational algebra and present a method, called a chase, for
enforcing a set of functional and full join dependencies on a relation
with null-values of type ``value exists, but is presently unknown''.
This novel chase can also be regarded as a generalization of
previously known chase methods. The title of the paper reflects the
emphasis of its contribution." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GRAHNE89A,
key	=	"Grahne" ,
author	=	"Grahne, G." ,
title	=	"{H}orn tables - an efficient tool for handling
incomplete information in databases" ,
booktitle=	sigmod ,
address	=	"Philadelphia, PA" ,
month	=	mar ,
year	=	"1989" ,
pages	=	"75--82" ,
abstract=	"The basic semantic assumption is that an
incomplete information database is a set of possible worlds (i.e. a
set of complete databases). The main issue is then the problem of
representing the set of possible worlds in a fashion that is suitable
for storing and processing the database. We have complemented the
representation hierachy with a construct called Horn tables. The class
of Horn tables is algebraically closed under any set of total
dependencies, and it is the only class in the hierarchy with this
property (apart from the top elements in the hierachy, which is of
theoretical interest only). All sets of dependencies consisting of
equality generating dependencies and one join dependency can be
efficiently incorporated into a Horn table. The certain answer to any
datalog query can be evaluated in polynomial time in the size of the
Horn table. The same is true for the possible answer to any positive
existential query. If one is concerned only with certain answers to
datalog queries, any set of dependencies can be efficiently
incorporated into a Horn table so that no corruption of the
information occurs w.r.t. the answers. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@phdthesis	( GRAHNE89B,
key	=	"Grahne" ,
author	=	"Grahne, G." ,
title	=	"{T}he {P}roblem of {I}ncomplete {I}nformation in
{R}elational {D}atabases" ,
year	=	"1989" ,
month	=	mar ,
school	=	"University of Helsinki, Finland" ,
)

@article	( GRANT77,
key	=	"Grant" ,
author	=	"Grant, J." ,
title	=	"{N}ull {V}alues in a {R}elational {D}ata {B}ase" ,
journal	=	"Information Processing Letters" ,
volume	=	"6" ,
number	=	"5" ,
month	=	"Oct" ,
year	=	"1977" ,
pages	=	"156--157" ,
keywords=	"Information systems, relational data base" ,
abstract=	"none" ,
bibdate	=	"Wed Jul 31 21:42:40 1991" ,
owner	=	"curtis" ,
)

@article	( GRANT79,
key	=	"Grant" ,
author	=	"Grant, J." ,
title	=	"{P}artial {V}alues in a {T}abular {D}atabase {M}odel" ,
journal	=	"Information Processing Letters" ,
volume	=	"9" ,
number	=	"2" ,
month	=	"Aug" ,
year	=	"1979" ,
pages	=	"97--99" ,
keywords=	"Partial values, relational database" ,
abstract=	"none" ,
bibdate	=	"Wed Jul 31 21:42:40 1991" ,
owner	=	"curtis" ,
)

@article	( GRANT80A,
key	=	"Grant" ,
author	=	"Grant, J." ,
title	=	"{I}ncomplete {I}nformation in a {R}elational {D}atabase" ,
journal	=	"Fundamenta Informatic\ae" ,
volume	=	"III" ,
number	=	"3" ,
year	=	"1980" ,
pages	=	"363--378" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( GRANT86,
key	=	"Grant \& Minker" ,
author	=	"Grant, J. and Minker, J." ,
title	=	"{A}nswering queries in indefinite databases and the
null value problem" ,
booktitle=	"Advances in Computing Research" ,
editor	=	"P. Kanellakis" ,
publisher=	"JAI Press" ,
address	=	"London" ,
year	=	"1986" ,
volume	=	"3" ,
pages	=	"247--267" ,
abstract=	"We investigate the notion of answering queries for
databases that may contain indefinite data. Such indefinite data is
represented as a disjunctive formula in first-order logic. We work
within a framework of database theories which contains the domain
closure axiom, the unique name axioms, and the equality axioms. In
addition, for negative information we use a Generalized Closed World
Assumption. Queries are also formulas in first-order logic, while
possible answers are disjunctions of tuples. We give an algorithm to
check if a candidate answer is in fact an answer. We also develop an
algorithm to find all minimal answers to a query. We show how the
problem of null values can be investigated as a special case of
incomplete information." ,
bibdate	=	"Wed Jul 31 21:42:40 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( GUNTZER91,
key	=	{G\"{u}ntzer et al.} ,
author	=	{G\"{u}ntzer, U. and Kiessling, W. and Th\"{o}ne,
H.} ,
title	=	"{N}ew {D}irections for {U}ncertainty {R}easoning in
{D}eductive {D}atabases" ,
booktitle=	sigmod ,
address	=	"Denver, CO" ,
month	=	may ,
year	=	"1991" ,
pages	=	"178--187" ,
abstract=	"This paper contributes a novel approach to
nonmontonic uncertainty reasoning, which is ubiquitous in many
real-life applications. Founded on the paradigm of conditional
probabilities we develop a rule-based calculus and prove that it is
sound, even in the presence of incomplete information. Thus the merits
of doing consistent judgements in uncertain domains and the advantages
of modularity and incrementality of rule-based application development
come together. We also can offer mechanisms to trace down collections
of uncertain rules. As next-generation applications will have to
handle vast amounts of uncertain data, an integration into databases
is mandatory. We give a direct implementation of our calculus on top
of a database system with a DATALOG-interface. In this way we extend
current database technology towards providing new applications with
new suitable primitives and with a database platform for coping with
uncertainty." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( HAAR77,
key	=	"Haar" ,
author	=	"Haar, R. L." ,
title	=	"{A} fuzzy relational data base system" ,
number	=	"TR-586" ,
institution=	"University of Maryland, Computer Center" ,
year	=	"1977" ,
month	=	sep ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( HAVRANEK80,
key	=	"Havr\'{a}nek" ,
author	=	"Havr\'{a}nek, T." ,
title	=	"{A}n {A}lternative {A}pproach to {M}issing {I}nformation in
the {GUHA} {M}ethod" ,
journal	=	"Kybernetika (Prague)" ,
volume	=	"16" ,
number	=	"22" ,
year	=	"1980" ,
pages	=	"145--155" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( HAWKES90,
key	=	"Hawkes et al." ,
author	=	"Hawkes, L. W. and Derry, S. J. and Rundensteiner,
E. A." ,
title	=	"{I}ndividualized tutoring using an intelligent fuzzy
temporal relational database" ,
journal	=	"International Journal on Man-Machine Studies" ,
volume	=	"33" ,
number	=	"4" ,
year	=	"1990" ,
pages	=	"409--429" ,
abstract=	"The student record (SR) is a major source of input
for any decision making done by an Intelligent Tutoring System (ITS)
and is a basis of the individualization in such systems. However, most
ITSs still have ``generalized'' student models which represent a type
of student rather than a particular one. Until the SR becomes truly
representative of each individual student, the goal of providing
individualized tutoring cannot be attained. In this paper we describe
an Intelligent Fuzzy Temporal Relational Database (IFTReD), an
intelligent system-independent SR which allows for almost any degree
of individualization the designer wishes to incorporate. It is
anticipated that this IFTReD will provide a significant improvement
over standard AI storage techniques for the SR. These improvements
will be realized in terms of: (1) intelligence; (2) greater storage
efficiency; (3) greater speed in retrieval and query; (4) ability to
handle linguistic codes, ranges, fuzzy possibilities, and incomplete
data in student models; (5) friendliness of query language; (6)
availability of temporal knowledge to give a history of past
performance; and (7) a more holistic view of the student permitting
greater individualization of the tutor." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( HEGNER87,
key	=	"Hegner" ,
author	=	"Hegner, S." ,
title	=	"{S}pecification and implementation of programs for
updating incomplete information databases" ,
booktitle=	pods ,
address	=	"San Diego, CA" ,
month	=	mar ,
year	=	"1987" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( HENRION93,
key	=	"Henrion \& Suermondt" ,
author	=	"Henrion, M. and Suermondt, J." ,
title	=	"{P}robabilistic and {B}ayesian {R}epresentations of
{U}ncertainty and {I}nformation {S}ystems: {A} {P}ragmatic {I}ntroduction" ,
booktitle=	"Proceedings of the Workshop on Uncertainty
Management in Information Systems: From Needs to Solutions" ,
address	=	"Avalon, Santa Catalina, California" ,
month	=	apr ,
year	=	"1993" ,
pages	=	"71--90" ,
abstract=	"" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( HENSCHEN86,
key	=	"Henschen \& Park" ,
author	=	"Henschen, L. J. and Park, H. S." ,
title	=	"{C}ompiling the {GCWA} in indefinite deductive
databases" ,
booktitle=	"Foundations of Deductive Databases and Logic
Programming" ,
editor	=	"J. Minker" ,
publisher=	"M. Kaufmann" ,
address	=	"Los Altos, CA" ,
year	=	"1986" ,
pages	=	"395--438" ,
abstract=	"This paper presents several fundamental results on
compiling the GCWA (Generalized Closed World Assumption) in IDDB
(Indefinite Deductive Databases). We do not allow function symbols,
but we do allow non-Horn clauses. Further, although the GCWA is used
to derive negative assumptions, we do allow also negative clauses to
occur explicitly. We show a fundamental relationship between
indefiniteness and GCWA inference. We consider three representation
alternatives to separate the CDB (Clausal DB) from the RDB (Relational
DB). We present the basic ideas and some effective ways for compiling
GCWA inference on the CDB and evaluating it though the RDB in a
non-recursive IDDB. We also present a basic idea on compiling the GCWA
in a recursive IDDB by a pattern generation method. Finally, we
introduce decomposition and evaluation theorems to evaluate
disjunctive and conjunctive ground queries." ,
bibdate	=	"Wed Jul 31 21:42:40 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( HENSCHEN86A,
key	=	"Henschen \& Park" ,
author	=	"Henschen, L. J. and Park, H. S." ,
title	=	"{I}ndefinite and {GCWA} {I}nference in {I}ndefinite
{D}eductive {D}atabases" ,
year	=	"1986" ,
pages	=	"191--197" ,
booktitle=	"Proc. AAAI-86" ,
)

@article	( HOMENDA91,
key	=	"Homenda" ,
author	=	"Homenda, W." ,
title	=	"{D}atabases with {A}lternative {I}nformation" ,
journal	=	tkde ,
publisher=	"IEEE" ,
volume	=	"3" ,
number	=	"3" ,
month	=	sep ,
year	=	"1991" ,
pages	=	"384--386" ,
abstract=	"A special kind of information-alternative
information-is considered in this work. Two different pieces of
information: I1 AND/OR I2 and EITHER I1 OR I2 are examples of
alternative information. Applicable models of data do not distinguish
information of this kind, but such a distinction, however, is
important in many circumstances. An attempt to distinguish and process
alternative information is made in this work." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( HULIN88C,
key	=	"Hulin" ,
author	=	"Hulin, G." ,
title	=	"{A} {P}roof-theoretic {P}erspective of {D}eductive
{D}atabases with {M}arked {N}ull {V}alues" ,
year	=	"1988" ,
number	=	"M273" ,
institution=	"Phillips Research Laboratory, Brussels" ,
month	=	dec ,
type	=	"Manuscript" ,
)

@techreport	( HULIN90B,
key	=	"Hulin" ,
author	=	"Hulin, G." ,
title	=	"{R}elational {D}atabases with {M}arked {N}ull {V}alues: {A}
{N}ew {A}pproach" ,
year	=	"1990" ,
number	=	"M333" ,
institution=	"Phillips Research Laboratory, Brussels" ,
month	=	jan ,
type	=	"Manuscript" ,
)

@techreport	( HULL84,
key	=	"Hull" ,
author	=	"Hull, R." ,
title	=	"{R}elative {I}nformation {C}apacity of {S}imple {R}elational
{D}atabase {S}chemata" ,
type	=	"TR" ,
number	=	"84-300" ,
institution=	"Computer Science Department, The University of
Southern California" ,
year	=	"1984" ,
month	=	jan ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( HURSON87,
key	=	"Hurson \& Miller" ,
author	=	"Hurson, A. and Miller, L." ,
title	=	"{D}atabase {M}achine {A}rchitecture for {S}upporting
{I}ncomplete {I}nformation" ,
journal	=	"Computer Systems Science and Engineering" ,
volume	=	"2" ,
number	=	"3" ,
month	=	jul ,
year	=	"1987" ,
pages	=	"107--116" ,
abstract=	" A growing number of users require information
from the database that cannot be obtained through the operators found
in traditional query languages. Such needs have increased the
expectation that a system will be able to assist the user in gathering
and interpreting the appropriate data. This paper examines the
inclusion of maybe-algebra operators in a database machine. In
addition, modifications designed to increase the time and space
efficiency of the operators as well as the quality of the results are
discussed. Finally, a revised set of maybe-algebra operators offering
improved performance is introduced." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( ICHIKAWA86,
key	=	"Ichikawa \& Hirakawa" ,
author	=	"Ichikawa, T. and Hirakawa, M." ,
title	=	"{ARES}: a relational database with the capability of
performing flexible interpretation of queries" ,
journal	=	tse ,
volume	=	"12" ,
number	=	"5" ,
month	=	may ,
year	=	"1986" ,
pages	=	"624--634" ,
keywords=	"Data similarity, query
representation/transformation, relational algebra, relational
database, similarity graph, similarity relation" ,
abstract=	"As the social demand on database utilization
expands, database systems are being directly handled more and more by
nonprofessionals. In this field, it is important that friendly
user-interfaces are provided. It has been found that nonprocedural
ways of describing queries such as QBE are preferred. A further step
toward attaining a higher degree of user-friendliness would be the
development of a way of enabling the system to perform a flexible
interpretation of queries usually specified definitely by the user. A
flexible interpretation is necessary so that data items which are
semantically close to an exact match with the query conditions can be
obtained. This paper presents a relational database system, ARES,
which has the capability of performing a flexible interpretation of
queries. In ARES, relational operations have been functionally
augmented with an additional comparison operator which implies
''approximately equal to'' or ``similar to'' for cases in which the
user expects the system to perform a flexible interpretation of the
query conditions. The functional augmentation is simply achieved by a
combination of conventional relational operations. ARES is now in
actual operation in a research environment, and will contribute to the
next step of our research toward implementation of highly intelligent
data processing facilities beyond the present scope of database
technology." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( IMIELINSKI81,
key	=	"Imieli\'{n}ski \& Lipski" ,
author	=	"Imieli\'{n}ski, T. and Lipski, W., Jr." ,
title	=	"{O}n {R}epresenting {I}ncomplete {I}nformation in a
{R}elational {D}atabase" ,
booktitle=	vldb ,
address	=	"Cannes, France" ,
month	=	sep ,
year	=	"1981" ,
pages	=	"388--397" ,
abstract=	"Precise conditions are formulated which should be
satisfied in a semantically meaningful extension of the usual
relational operators of projection, selection, union, and join, from
operators on relations to operators on tables with ``null values'' of
various kinds allowed. These conditions require that our system be
safe in the sense that no incorrect conclusion is derivable by using a
specified subset $\Omega$ of the relational operators; and that it be
complete in the sense that all valid conclusions expressible by
relational expressions using operators in $\Omega$ are in fact
derivable in our system. Examples of three such systems are studied in
more detail. The effect of dependencies of various kinds is briefly
discussed." ,
bibdate	=	"Sun Apr  7 17:11:20 1991" ,
owner	=	"curtis" ,
)

@phdthesis	( IMIELINSKI81A,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{P}roblems of representing information in relational
databases (in {P}olish)" ,
school	=	"Institute of Computer Science, Polish Academy of
Sciences" ,
year	=	"1981" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( IMIELINSKI83,
key	=	"Imieli\'{n}ski \& Lipski" ,
author	=	"Imieli\'{n}ski, T. and Lipski, W., Jr." ,
title	=	"{I}ncomplete {I}nformation and {D}ependencies in
{R}elational {D}atabases" ,
booktitle=	sigmod ,
address	=	"Orlando, FL" ,
month	=	jun ,
year	=	"1983" ,
pages	=	"178--184" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( IMIELINSKI84,
key	=	"Imieli\'{n}ski \& Lipski" ,
author	=	"Imieli\'{n}ski, T. and Lipski, W., Jr." ,
title	=	"{I}ncomplete {I}nformation in {R}elational {D}atabases" ,
journal	=	jacm ,
volume	=	"31" ,
number	=	"4" ,
year	=	"1984" ,
pages	=	"761--791" ,
keywords=	"Relational database, incomplete information, null
values, marked nulls, relational algebra, query language semantics,
query processing" ,
abstract=	"This paper concerns the semantics of Codd's
relational model of data. Formulated are precise conditions that
should be satisfied in a semantically meaningful extension of the
usual relational operators, such as projection, selection, union, and
join, from operators on tables with ``null values'' of various kinds
allowed. These conditions require that the system be safe in the sense
that no incorrect conclusion is derivable by using a specified subset
$\Omega$ of the relational operators; and that it be complete in the
sense that all conclusions expressible by relational expressions using
operators in $\Omega$ are in fact derivable in this system. Two such
systems of practical interest are shown. The first, based on the usual
Codd's null values, supports projection and selection. The second,
based on many different (``marked'') null values or variables allowed
to appear in a table, is shown to correctly support projection,
positive selection (with no negation occurring in the selection
condition), union, and renaming of attributes, which allows for
processing arbitrary conjunctive queries. A very desirable property
enjoyed by this system is that all relational operators on tables are
performed in exactly the same way as in the case of the usual
relations. A third system, mainly of theoretical interest, supporting
projection, selection, union, join, and renaming, is also discussed.
Under a so-called closed world assumption, it can also handle the
operator of difference. It is based on a device called a conditional
table and is crucial to the proof of the correctness of the second
system. All systems considered allow for relational expressions
containing arbitrarily many different relation symbols, and no form of
the universal relation assumption is required." ,
bibdate	=	"Mon Apr  1 15:18:35 1991" ,
owner	=	"curtis" ,
)

@incollection	( IMIELINSKI84A,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{O}n {A}lgebraic {Q}uery {P}rocessing in {L}ogical {D}atabases" ,
booktitle=	"Advances in Data Base Theory" ,
editor	=	"H. Gallaire and J. Minker and J.M. Nicolas" ,
publisher=	"Plenum Press" ,
address	=	"New York" ,
year	=	"1984" ,
volume	=	"2" ,
pages	=	"285--318" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( IMIELINSKI86A,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{Q}uery {P}rocessing in {D}eductive {D}atabases with
{I}ncomplete {I}nformation" ,
type	=	"TR" ,
number	=	"177" ,
institution=	"Rutgers University" ,
year	=	"1986" ,
month	=	mar ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( IMIELINSKI86B,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{A}utomated {D}eduction in {D}atabases with {I}ncomplete
{I}nformation" ,
type	=	"TR" ,
number	=	"181" ,
institution=	"Rutgers University" ,
year	=	"1986" ,
month	=	mar ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( IMIELINSKI86C,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{Q}uery {P}rocessing in {D}eductive {D}atabases with
{I}ncomplete {I}nformation" ,
booktitle=	sigmod ,
year	=	"1986" ,
pages	=	"268--280" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( IMIELINSKI86D,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{A}utomated {D}eduction in {D}atabases with {I}ncomplete
{I}nformation" ,
booktitle=	"Preprints of Workshop: Foundations of Deductive
Databases and Logic Programming" ,
year	=	"1986" ,
pages	=	"242--283" ,
address	=	"Washington, D.C." ,
month	=	aug ,
)

@inproceedings	( IMIELINSKI89,
key	=	"Imieli\'{n}ski \& Vadaparty" ,
author	=	"Imieli\'{n}ski, T. and Vadaparty, K." ,
title	=	"{C}omplexity of query processing in databases with
or-objects" ,
booktitle=	pods ,
year	=	"1989" ,
pages	=	"51--65" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( IMIELINSKI89A,
key	=	"Imieli\'{n}ski" ,
author	=	"Imieli\'{n}ski, T." ,
title	=	"{I}ncomplete {I}nformation in {L}ogical {D}atabases" ,
journal	=	"IEEE Database Engineering Bulletin - Special Issue
on Imprecision in Databases" ,
volume	=	"12" ,
number	=	"2" ,
month	=	jun ,
year	=	"1989" ,
pages	=	"29--40" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@incollection	( IMIELINSKI89B,
key	=	"Imieli\'{n}ski \& Lipski" ,
author	=	"Imieli\'{n}ski, T. and Lipski, W., Jr." ,
title	=	"{E}pilogue to `{I}ncomplete {I}nformation in a
{R}elational {D}atabase'" ,
booktitle=	"Readings in Artificial Intelligence and Databases" ,
editor	=	"M.L. Brodie and J. Mylopoulos" ,
publisher=	"Springer-Verlag" ,
address	=	"Berlin and New York" ,
year	=	"1989" ,
abstract=	"do not have article" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( IMIELINSKI91,
key	=	"Imieli\'{n}ski et al." ,
author	=	"Imieli\'{n}ski, T. and Naqvi, S. and Vadaparty, K." ,
title	=	"{I}ncomplete {O}bjects---{A} {D}ata {M}odel for {D}esign and
{P}lanning {A}pplications" ,
booktitle=	sigmod ,
address	=	"Denver, CO" ,
month	=	may ,
year	=	"1991" ,
pages	=	"288--297" ,
abstract=	"We are motivated by applications within design,
planning and scheduling areas, where current research appears to be
focused on syntactic issues of performance and volume. We take a more
semantic view of applications within these areas and discover several
useful functionalities that are poorly supported. For example,
facilities for handling incomplete specifications are quite
inadequate. We introduce a notion of OR-objects and show that it
captures incomplete specifications naturally. In particular a database
with OR-objects represents a set of possible worlds, e.g., a world for
each design or schedule, and queries can either be evaluated in the
``interpretations'' of the database, or in the database itself. We
formalize these notions of interpretations and hypothetical queries in
an object-oriented setting, and provide a complexity characterization
for our queries." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( IMIELINSKI91A,
key	=	"Imieli\'{n}ski et al." ,
author	=	"Imieli\'{n}ski, T. and Naqvi, S. and Vadaparty, K." ,
title	=	"{Q}uerying {D}esign and {P}lanning {D}atabases" ,
booktitle=	"Proc. of the Int. Conf. on Deductive and
Object-Oriented Databases (DOOD'91)" ,
address	=	"Munich, Germany" ,
month	=	dec ,
year	=	"1991" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( JAEGERMANN78,
key	=	"Jaegermann" ,
author	=	"Jaegermann, M." ,
title	=	"{I}nformation storage and retrieval systems with
incomplete information" ,
journal	=	"Fundamenta Informatic\ae" ,
volume	=	"II" ,
year	=	"1978" ,
pages	=	"17--41" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( JIA92,
key	=	"Jia et al." ,
author	=	"Jia, Y. and Feng, Z. and Miller, M." ,
title	=	"{A} {M}ultivalued {A}pproach to {H}andle {N}ulls in {RDB}" ,
booktitle=	"Future Database'92, Proceedings of the Second
Far-East Workshop on Future Database Systems" ,
address	=	"Kyoto, Japan" ,
month	=	apr ,
year	=	"1992" ,
pages	=	"71--76" ,
abstract=	" To handle incomplete data in Database and
Information systems is a nontrivial problem. There is no fully
satisfactory design theory incorporating null values in Relational
Database systems. In this paper we present our multivalued logical
proposal to deal with null values in Relational Datanases. This method
is different from classifying nulls into multi categories, such as
Codd's four valued logic which classified nulls into applicable and
inapplica ble nulls, respectively. We believe that four valued logic
cannot cover all possible nulls, and neither can n+1 valued logic. Our
multivalued logical approach is based on traditional three valued
logic, which gives each null value a possible truth degree. The result
of a query will depend on truth degrees of the nulls involved, giving
a 'probabilistic' response to the query. To deal with null values of
various truth degrees we introduce an augmented set of relational and
logical operations. An arithematic operation approach for nulls is
introduced, which we believe can be extended for traditional
relational algebra. To simplify the handling of nulls by a RDBMS, a
measurement of null truth level is proposed. According to the truth
level of a null, RDBMS can decide whether to use it in calculation or
ignore it. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( JICHAO87,
key	=	"Jichao" ,
author	=	"Jichao, H." ,
title	=	"{E}xtending relational model to deal with null value
(in {C}hinese)" ,
journal	=	"Chinese Journal of Computation" ,
volume	=	"10" ,
number	=	"8" ,
year	=	"1987" ,
pages	=	"449--459" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( JOHNSON91,
key	=	"Johnson" ,
author	=	"Johnson, C. A." ,
title	=	"{H}andling indefinite and negative data in a
deductive database" ,
journal	=	"Data \& Knowledge Engineering" ,
volume	=	"6" ,
number	=	"4" ,
month	=	jul ,
year	=	"1991" ,
pages	=	"333--348" ,
keywords=	"Deductive databases; indefinite data; negative
data; closed world metarules;; Bibel's connection method" ,
abstract=	"We introduce the notion of a minimal
interpretation of an indefinite deductive database and present a
closed world metarule based on this notion with which negative data
may be inferred from the database. We also investigate a possible
implementation of our metarule using a path checking algorithm adapted
from Bibel`s connection method." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( KACPRZYK86,
key	=	"Kacprzyk \& Ziolkowski" ,
author	=	"Kacprzyk, J. and Ziolkowski, A." ,
title	=	"{D}atabase queries with fuzzy linguistic quantifiers" ,
journal	=	"IEEE Trans. Syst. Man Cybern. SMC-16" ,
volume	=	"3" ,
month	=	"May/June" ,
year	=	"1989" ,
pages	=	"474--479" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( KACPRZYK89,
key	=	"Kacprzyk et al." ,
author	=	"Kacprzyk, J. and Zadrozny, S. and Ziolkowski, A." ,
title	=	"{FQUERY} {III} plus. {A} 'human-consistent' database
querying system based on fuzzy logic with linguistic quantifiers" ,
journal	=	"Information Sciences" ,
volume	=	"14" ,
number	=	"6" ,
pages	=	"???--???" ,
year	=	"1989" ,
abstract=	" Using a fuzzy-logic-based calculus of
linguistically quantified propositions we present FQUERY III plus , a
new, more 'human-friendly' and easier-to-use implementation of a
querying scheme proposed originally by J. Kacprzyk and A. Ziolkowski
to handle imprecise queries including a linguistic quantifier as, e.g.
'find all records in which most (almost all, much more than 75%,...or
any other linguistic quantifier) of the important attributes (out of a
specified set) are as desired (e.g. equal to five, more than 10,
large, more or less equal to 15, etc.) FQUERY III plus is an 'add-on'
to Ashton- Tate's dBase III Plus. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KAMEL88,
key	=	"Kamel et al." ,
author	=	"Kamel, M. S. and Loo, W. S. and Wong, A. K. C." ,
title	=	"{I}ntelligent database query translation" ,
booktitle=	"Proceedings of the 1988 IEEE International
Conference on Systems, Man, and Cybernetics" ,
address	=	"Beijing/Shenyang, China" ,
month	=	aug ,
year	=	"1988" ,
pages	=	"665--669" ,
abstract=	" The authors discuss techniques for processing
database queries that are not required to be formulated based on
complete and precise knowledge of the query specification as defined
in the database management system. Specific attention is given to
processing queries that are ill-defined, not complete, and fuzzy. The
authors propose a query translator that tries to bridge the gap
between the user's semantically stated query and its full
specification as required by the database. The translator utilizes a
graph-based structure to represent queries and relations in the
database. The translator transforms a logical query graph, modeling a
user's query (which may be ill-defined), into a complete query graph
which provides the detailed description of the query, allowing
corrective responses. An intermediate query language (IQL) has been
developed to serve as input to the translator. The translator has been
implemented using Interlisp-D, and its performance has been
demonstrated. " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( KAMEL90,
key	=	"Kamel et al." ,
author	=	"Kamel, M. S. and Hadfield, B. and Ismail, M." ,
title	=	"{F}uzzy {Q}uery {P}rocessing using {C}lustering {T}echniques" ,
journal	=	"Information Processing \& Management" ,
volume	=	"26" ,
number	=	"2" ,
year	=	"1990" ,
pages	=	"279--293" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KAO87,
key	=	"Kao et al." ,
author	=	"Kao, M. and Cercone, N. and Luk, W." ,
title	=	"{W}hat do you mean ``{N}ull''? {T}urning {N}ull {R}esponses
into {Q}uality {R}esponses" ,
booktitle=	"Proceedings of the Third International Conference
on Data Engineering" ,
year	=	"1987" ,
pages	=	"356--364" ,
abstract=	"When natural language {\em front-ends} are
introduced to database management systems, generation of quality
responses have proven problematical in situations when null values
arise. In our work, in which we assume the database query language is
SQL, we present methods for responding with appropriate answers to
null value responses. To do so we use a knowledge base based on RM/T,
an extended relational model proposed by E. F. Codd. The advantages of
this approach are described. To demonstrate the utility of the
knowledge base, a simple knowledge base is constructed. A detailed
algorithm is given to provide additional information when a null
answer is returned." ,
bibdate	=	"Wed Jul 31 09:59:23 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KELLER84B,
key	=	"Keller \& Wilkins" ,
author	=	"Keller, A. M. and Wilkins, M. W." ,
title	=	"{A}pproaches for {U}pdating {D}atabases {W}ith {I}ncomplete
{I}nformation and {N}ulls" ,
booktitle=	"Proceedings of the International Conference on
Data Engineering" ,
organization=	"IEEE Computer Society" ,
publisher=	"IEEE Computer Society Press" ,
address	=	"Los Angeles, CA" ,
month	=	apr ,
year	=	"1984" ,
pages	=	"332--340" ,
keywords=	"null values, incomplete information, updates,
databases, relational databases" ,
abstract=	"In this paper we consider approaches to updating
databases containing null values and incomplete information. Our
approach distinguishes between modeling incompletely known worlds and
modeling changes in these worlds. As an alternative to the open and
closed world assumptions, we propose the modified closed world
assumption. Along with the discussion of updating, we address some
issues of refining incompletely specified information." ,
bibdate	=	"Wed Sep  2 14:16:04 1987" ,
owner	=	"mckenzie" ,
)

@article	( KELLER85C,
key	=	"Keller \& Wilkins" ,
author	=	"Keller, A. M. and Wilkins, M. W." ,
title	=	"{O}n the {U}se of an {E}xtended {R}elational {M}odel to
{H}andle {C}hanging {I}ncomplete {I}nformation" ,
journal	=	tse ,
publisher=	"IEEE" ,
volume	=	"SE-11" ,
number	=	"7" ,
month	=	jul ,
year	=	"1985" ,
pages	=	"620--633" ,
keywords=	"Databases; incomplete information; null values;
relational databases; updates" ,
abstract=	"In this paper we consider approaches to updating
databases containing null values and incomplete information. Our
approach distinguishes between modeling incompletely known worlds and
modeling changes in these worlds. As an alternative to the open and
closed world assumptions, we propose the expanded closed world
assumption. Under this assumption, we discuss how to perform updates
on databases containing set nulls, marked nulls, and simple
conditional tuples, and address some issues of refining incompletely
specified information." ,
bibdate	=	"Tue Jan 20 12:22:53 1987" ,
owner	=	"manning" ,
)

@article	( KELLER86A,
key	=	"Keller" ,
author	=	"Keller, A. M." ,
title	=	"{S}et-theoretic {P}roblems of {N}ull {C}ompletion in
{R}elational {D}atabases" ,
journal	=	"Information Processing Letters" ,
volume	=	"22" ,
number	=	"5" ,
month	=	"April" ,
year	=	"1986" ,
pages	=	"261--265" ,
keywords=	"relational databases, null values, set theory,
incomplete information, x-relation" ,
abstract=	"When considering using databases to represent
information, the relationship between two facts where one may imply
the other needs to be addressed. In relational databases, this
question becomes whether null completion is assumed. That is, does a
(possibly partially-defined) tuple imply the existence of tuples that
are ``less informative'' than the original tuple. We show that no
relational algebra, that assumes equivalence under null completion,
can include set-theoretic operators that are compatible with ordinary
set theory. Thus, the approach of x-relations is incompatible with the
axioms of a boolean algebra." ,
bibdate	=	"Wed Aug 19 21:42:40 1987" ,
owner	=	"mckenzie" ,
)

@article	( KENT91,
key	=	"Kent" ,
author	=	"Kent, W." ,
title	=	"{T}he {B}reakdown of the {I}nformation {M}odel in
{M}ulti-{D}atabase {S}ystems" ,
journal	=	sigmod ,
volume	=	"20" ,
number	=	"4" ,
year	=	"1991" ,
pages	=	"10--15" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KENT91A,
key	=	"Kent" ,
author	=	"Kent, W." ,
title	=	"{S}olving {D}omain {M}ismatch and {S}chema {M}ismatch
{P}roblems with an {O}bject-{O}riented {D}atabase {P}rogramming {L}anguage" ,
booktitle=	vldb ,
address	=	"Barcelona, Spain" ,
year	=	"1991" ,
pages	=	"147--160" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KIESSLING92,
author	=	{Kiessling, W. and Th\"{o}ne, H. and G\"{u}ntzer,
U.} ,
title	=	"{D}atabase {S}upport for {P}roblematic {K}nowledge" ,
year	=	"1992" ,
booktitle=	"Proc. EDBT92 International Conference on Extending
Database Technology" ,
address	=	"Vienna, Austria" ,
)

@inproceedings	( KIFER88,
key	=	"Kifer \& Li" ,
author	=	"Kifer, M. and Li, A." ,
title	=	"{O}n the {S}emantics of {R}ule-{B}ased {E}xpert {S}ystems with
{U}ncertainty" ,
booktitle=	"Proceedings of the International Conference on
Database Theory" ,
publisher=	"Springer-Verlag" ,
year	=	"1988" ,
pages	=	"102--117" ,
abstract=	"We present a formal semantics for rule-based
systems with uncertainty (this field has also become known as
``quantitative logic programming''). Unlike previous works, our
framework is general enough to accommodate most of the known schemes
of reasoning with uncertainty found in the existing expert systems. We
provide a rigorous treatment of the issue of evidential independence,
and study its impact on the semantics. To the best of our knowledge,
this issue has not been addressed before in the literature on
quantitative logic programming. In expert systems evidential
independence received only an ad hoc treatment, while the approaches
found in the theory of evidential reasoning are feasible only in small
scale systems. We discuss the problem of query optimization and, as a
first-step, present a quantitative semi-naive query evaluation
algorithm -- generalization of a method well-known in deductive
databases. Treatment of negation and conflicting evidence based on, so
called, support logic is given in the last part of the paper, where we
extend the semantics of stratified programs to deal with uncertainty." ,
bibdate	=	"Wed Jul 31 14:17:36 1991" ,
owner	=	"curtis" ,
)

@article	( KING91,
key	=	"King \& Small" ,
author	=	"King, P. and Small, C." ,
title	=	"{D}efault {D}atabases and {I}ncomplete {I}nformation" ,
journal	=	"Computer Journal" ,
volume	=	"34" ,
number	=	"3" ,
month	=	jun ,
year	=	"1991" ,
pages	=	"239--244" ,
abstract=	" We present the concept of a default database
which comprises a set of facts, a set of deduction rules, and a set of
defaults. Defaults define assumptions to be made about information not
derivable from the rules and facts. Defaults, by augmenting the
information which is a consequence solely of the rules and facts,
enable definite responses to queries on the basis of 'common sense'
assumptions rather than responses of the form 'unknown'. The augmented
information is termed an extension. Although such an extension is
self- consistent, in general two or more mutually inconsistent
extensions can arise. We characterise the rules and defaults of a
database as safe if only one extension can arise for any given set of
facts. We give conditions which are necessary and sufficient to ensure
safety." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@book		( KLIR88,
key	=	"Klir \& Folger" ,
author	=	"Klir, G. J. and Folger, T. A." ,
title	=	"{F}uzzy {S}ets, {U}ncertainty and {I}nformation" ,
publisher=	"Prentice-Hall" ,
address	=	"Englewood Cliffs, NJ" ,
year	=	"1988" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@article	( KOCHAREKAR89,
key	=	"Kocharekar" ,
author	=	"Kocharekar, R." ,
title	=	"{N}ulls in {R}elational {D}atabases: {R}evisited" ,
journal	=	sigmod ,
volume	=	"18" ,
number	=	"1" ,
month	=	mar ,
year	=	"1989" ,
pages	=	"68--73" ,
abstract=	"This paper discusses the semantic issues related
to null values problem in relational databases. We argue that the
proposed set of maybe operations with the three valued logic is still
not adequate and needs further enhancements." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KORNATZKY93,
key	=	"Kornatzky \& Shimony" ,
author	=	"Kornatzky, Y. and Shimony, S." ,
title	=	"{A} {P}robabilistic {S}patial {D}ata {M}odel" ,
booktitle=	"DEXA'93" ,
address	=	"Prague, Czech Republic" ,
month	=	sep ,
year	=	"1993" ,
abstract=	"Spatial information in autonomous robot tasks is
uncertain due to measurement errors, the dyntamic nature of the world,
and an incompletely known environment. We present a probabilistic
spatial data model capable of describing relevant spatial data, such
as object location, shape, composition, and other parameters, in the
presence of uncertainty. Uncertain spatial information is modeled
through continuous probability distributions on values of attributes.
The data model is designed to support our visual tracking and
navigation prototype." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( KORNATZKY93A,
key	=	"Kornatzky \& Shimony" ,
author	=	"Kornatzky, Y. and Shimony, S." ,
title	=	"{A} {P}robabilistic {O}bject-{O}riented {D}ata {M}odel" ,
type	=	"TR" ,
number	=	"FC 93-04" ,
institution=	"Ben-Gurion University" ,
year	=	"1993" ,
month	=	may ,
abstract=	"Intelligent systems such as autonomous robots
interacting with the real world encounter uncertainty in their
knowledge about the world, due to incomplete information, data
acquisition errors, and uncertainty about cause and effect. To operate
in such an environment, uncertain information needs to be represented
explicitly in their world model (database). We present an
object-oriented data model that describes uncertainty through the use
of probabilities. The model represents uncertainty with respect to
values of attributes, and with respect to class hierarchy." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KOUBARAKIS93,
key	=	"Koubarakis" ,
author	=	"Koubarakis, M." ,
title	=	"{R}epresentation and {Q}uerying in {T}emporal {D}atabases:
the {P}ower of {T}emporal {C}onstraints" ,
booktitle=	"Proceedings of the International Conference on
Data Engineering" ,
address	=	"Vienna, Austria" ,
month	=	apr ,
pages	=	"327--334" ,
year	=	"1993" ,
abstract=	"We propose a temporal database model capable of
representing absolute, relative, imprecise and indefinite temporal
data. Our model is based on temporal tables i.e., relation-like
representations which can contain variables constrained by the
formulas of a temporal theory. We define an algebraic query language
for temporal tables and discuss some problems related to query
answering." ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@techreport	( KOURAMAJIAN92,
key	=	"Kouramajian \& Elmasri" ,
author	=	"Kouramajian, V. and Elmasri, R." ,
title	=	"{A} {G}eneralized {T}emporal {M}odel" ,
type	=	"Tech. Report" ,
institution=	"University of Texas at Arlington" ,
year	=	"1992" ,
month	=	feb ,
abstract=	" " ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KRATZER85,
key	=	"Kratzer and Schreier" ,
author	=	"Kratzer, K. and Schreier, U" ,
title	=	"{B}ehandlung von {A}usnahmesituationen mit einer
{M}etadatenbank" ,
booktitle=	{Proc. GI-Fachtagung, Datenbank-Systeme f\"ur
B\"uro, Technik und Wissenschaft, Germany} ,
address	=	"Karlsruhe, Germany" ,
year	=	"1985" ,
abstract=	"do not have" ,
bibdate	=	"Mon Apr  1 15:20:41 1991" ,
owner	=	"curtis" ,
)

@inproceedings	( KURUTACH93,
key	=	"Kurutach \& Franklin" ,
author	=	"Kurutach, W. and Franklin, J." ,
title	=	"{O}n {T}emporal-fuzziness in {T}emporal {F}uzzy {D}atabases" ,
booktitle=	"DEXA'93" ,
address	=	"Prague, Czech Republic" ,
month	=	sep ,
year	=	"1993" ,
pages	=	"154--165" ,
abstract=	"We propose a framework for a database model
unifying both imprecision and time aspects of data. Particularly, we
emphasize that the fuzzy meanings of linguistic data can change with
time; we call this property temporal-fuzziness. The major problems
arising from the lack of the ability to handle this property have been
studied, i.e. users and databases misinterpret the meaning of data.
Thus, it is essential to treat temporal-fuzziness within an
appropriate framework like ours. In our work, we employ concepts based
on fuzzy set theory - possibility theory and linguistic variables -
for modeling and evaluating uncertain/imprecise data from three domain
types, i.e.. quantitative, qualitative, and multivalued logic data
domains. To model past data, the tuple time stamping method and the
discrete time conceptual model are utilized. We introduce three kinds
of measures for each domain ty