waashk/acm huggingface dataset:
the extension of data abstraction to database management  the long- term goal of the user software engineering (use) project at the university of california, san francisco, is to provide an integrated homogeneous programming environment for the design and development of interactive information systems. realization of this goal involves the development of new software tools, their integration with existing tools, and the creation of an information system development methodology in which these tools are systematically used [1,2].  the successful construction of interactive information systems requires the utilization of principles of user-centered design [3,4,5], combined with features traditionally associated with the separate areas of programming languages, operating systems, and data base management [6]. it has become increasingly clear that the key to being able to provide such a unified view lies in providing a unified view of data [7]. the potential benefits of such a unification are considerable, including:  1) conceptual simplification of the system structure permitting, for example, joint design of data structures and data bases  2) the elimination of duplication or inconsistencies among diverse software components  3) the ability to achieve greater reliability in systems because of reduced dependence upon multiple software systems  anthony i. wasserman
introduction to the electronic symposium on computer-supported cooperative work  computer-supported cooperative work (cscw) holds great importance and promise for modern society. this paper provides an overview of seventeen papers comprising a symposium on cscw. the overview also discusses some relationships among the contributions made by each paper, and places those contributions into a larger context by identifying some of the key challenges faced by computer science researchers who aim to help us work effectively as teams mediated through networks of computers. the paper also describes why the promise of cscw holds particular salience for the u.s military. in the context of a military setting, the paper describes five particular challenges for cscw researchers. while most of these challenges might seem specific to military environments, many others probably already face similar challenges, or soon will, when attempting to collaborate through networks of computers. to support this claim, the paper includes a military scenario that might hit fairly close to home for many, and certainly for civilian emergency response personnel. after discussing the military needs for collaboration technology, the paper briefly outlines the motivation for a recent darpa research program along these lines. that program, called intelligent collaboration and visualization, sponsored the work reported in this symposium.  kevin l. mills
hierarchical indexing and document matching in bow  bow is an on-line bibliographical repository based on a hierarchical c oncept index to which entries are linked. searching in the repository should therefore return matching topics from the hierarchy, rather than just a list of entries. likewise, when new entries are inserted, a search for relevant topics to which they should be linked is required. we develop a vector-based algorithm that creates keyword vectors for the set of competing topics at each node in the hierarchy, and show how its performance improves when domain- specific features are added (such as special handling of topic titles and author names). the results of a 7-fold cross validation on a corpus of some 3,500 entries with a 5-level index are hit ratios in the range of 89-95%, and most of the misclassifications are indeed ambiguous to begin with.  maayan geffet dror g. feitelson
using multiversioning to improve performance without loss of consistency (abstract only) abstract  oracle first implemented multiversioning, which was called readconsistency, in version 4 (ea. 1983) of the kernel. it supportedthe old master/new master programming paradigm for both applicationbuilders and query-processor implementors while avoiding thereader/writer serialization that results from using automatic sharelocks. the resulting transaction consistency model was arcane, notexactly serializable, but pragmatic in actual use. in this session,mr. bamford will cover read consistency from a number ofviewpoints. first, the model will be described and a little detailabout oracles current implementation will be given. next, theconsequences of having read consistency as part of the databasescore architecture will be discussed. in particular, the effects onthe designs for row locking, query processing, distributed query,distributed cache coherence, referential integrity, and set updateswill be described. this will be followed by a comparison of oraclesread consistency model to other common concurrency models, lookingat cost and throughput under a variety of workloads, finally, mr.barnford will propose how oracle intends to carry read consistencyinto the future as support is added for complex objects,distributed computations, and long transactions.  roger bamford
the failure and recovery problem for replicated databases  a replicated database is a distributed database in which some data items are stored redundantly at multiple sites. the main goal is to improve system reliability. by storing critical data at multiple sites, the system can operate even though some sites have failed. however, few distributed database systems support replicated data, because it is difficult to manage as sites fail and recover.  a replicated data algorithm has two parts. one is a discipline for reading and writing data item copies. the other is a concurrency control algorithm for synchronizing those operations. the read-write discipline ensures that if one transaction writes logical data item ×, and another transaction reads or writes x, there is some physical manifestation of that logical conflict. the concurrency control algorithm synchronizes physical conflicts; it knows nothing about logical conflicts. in a correct replicated data algorithm, the physical manifestation of conflicts must be strong enough so that synchronizing physical conflicts is sufficient for correctness.  this paper presents a theory for proving the correctness of algorithms that manage replicated data. the theory is an extension of serializability theory. we apply it to three replicated data algorithms: gifford's "quorum consensus" algorithm, eager and sevcik's "missing writes" algorithm, and computer corporation of america's "available copies" algorithm.  philip a. bernstein nathan goodman
on the contributions of different empirical data in usability testing  many sources of empirical data can be used to evaluate an interface (e.g., time to learn, time to perform benchmark tasks, number of errors on benchmark tasks, answers on questionnaires, comments made in verbal protocols). this paper examines the relative contributions of both quanti?tive and qualitative data gathered during a usability study. for each usability problem uncovered by this study, we trace each contributing piece of evidence back to its empirical source. for this usability study, the verbal protocol provided the sole source of evidence for more than one third of the most severe problems and more than two thirds of the less severe problems. thus, although the verbal protocol provided the bulk of the evidence, other sources of data contributed disproportionately to the more critical problems. this work suggests that further research is required to determine the relative value of different forms of empirical evidence.  maria r. ebling bonnie e. john
partitioning digital worlds: focal and peripheral awareness in multiple monitor use  software today does not help us partition our digital worlds effectively. we must organize them ourselves. this field study of users of multiple monitors examines how people with a lot of display space arrange information. second monitors are generally used for secondary activities related to principal tasks, for peripheral awareness of information that is not the main focus, and for easy access to resources. a second monitor improves efficiency in ways that are difficult to measure yet can have substantial subjective benefit. the study concludes with illustrations of shortcomings of today's systems and applications: the way we work could be improved at relatively low cost.  jonathan grudin
frame-axis model for automatic information organizing and spatial navigation  in taxonomic reasoning tasks, such as scientific research or decision making, people gain insight and find new ideas through analysis of large numbers of factual data or material documents, which are generally disorganized and unstructured. hypermedia technology provides effective means of organizing and browsing information with such nature. however, for large amounts of information, the conventional node-link model makes linking or browsing operations be complicated because their relationship have to be represented as binary relations. in this paper, we propose a hypermedia data model call frame-axis model, which represents relationship between information as n-ary relations on mapped space. also, the automatic information organizing mechanism which is based on this data model and the browsing interface hypercharts which employ spatial layout are provided. finally, we show some browsing examples on our working prototype system, castingnet.  yoshihiro masuda yasuhiro ishitobi manabu ueda
a parallel data base machine for query translation in a distributed database system  a special purpose data base machine (dbm) designed to translate queries between data models is examined. the dbm will provide a means of direct communication between different dbmss in a distributed database system. the design utilizes the concept of parallelism to handle simultaneous queries and to improve the performance of the translation with respect to cost and time. the components of the dbm are described and an example is provided to illustrate the stages of the query translation utilizing the proposed dbm.  m. mehdi owrang o. massoud omidvar
the limits of expert performance using hierarchic marking menus  a marking menu allows a user to perform a menu selection by either popping-up a radial (or pie) menu, or by making a straight mark in the direction of the desired menu item without popping-up the menu. a hierarchic marking menu uses hierarchic radial menus and "zig-zag" marks to select from the hierarchy. this paper experimentally investigates the bounds on how many items can be in each level, and how deep the hierarchy can be, before using a marking to select an item becomes too slow or prone to errors.  gordon kurtenbach william buxton
interactive visualization of video metadata  much current research on digital libraries focuses on named entityextraction and transformation into structured information. examples include entities like events, people, and places, and attributes like birth date or latitude. this video demonstration illustrates the potential for finding relationships among entities extracted from 50,000 news segments from cmus informedia digital video library. a visual query language is used to specify relationships among entities. data populate the query structure, which becomes an interface for exploration that gives continuous feedback in the form of visualizations of summary statistics. the target user is a data analyst familiar with the domain from which the entities come, but not a computer scientist.  mark derthick
spatial join selectivity using power laws  we discovered a surprising law governing the spatial join selectivity across two sets of points. an example of such a spatial join is "_find the libraries that are within 10 miles of schools_". our law dictates that the number of such qualifying pairs follows a power law, whose exponent we call "pair-count exponent" (pc). we show that this law also holds for self-spatial-joins ("_find schools within 5 miles of other schools_") in addition to the general case that the two point-sets are distinct. our law holds for many real datasets, including diverse environments (geographic datasets, feature vectors from biology data, galaxy data from astronomy).  in addition, we introduce the concept of the box-occupancy-product-sum (bops) plot, and we show that it can compute the pair-count exponent in a timely manner, reducing the run time by orders of magnitude, from quadratic to linear. due to the pair-count exponent and our analysis (law 1), we can achieve accurate selectivity estimates in constant time (o(1)) without the need for sampling or other expensive operations. the relative error in selectivity is about 30% with our fast bops method, and even better (about 10%), if we use the slower, quadratic method.  christos faloutsos bernhard seeger agma traina caetano traina
the role of kinesthetic reference frames in two-handed input performance  we present experimental work which explores how the match (or mismatch) between the input space of the hands and the output space of a graphical display influences two-handed input performance. during interaction with computers, a direct correspondence between the input and output spaces is often lacking. not only are the hands disjoint from the display space, but the reference frames of the hands may in fact be disjoint from one another if two separate input devices (e.g. two mice) are used for two-handed input. in general, we refer to the workspace and origin within which the hands operate as kinesthetic reference frames. our goal is to better understand how an interface designer's choice of kinesthetic reference frames influences a user's ability to coordinate two-handed movements, and to explore how the answer to this question may depend on the availability of visual feedback. understanding this issue has implications for the design of two-handed interaction techniques and input devices, as well as for the reference principle of guiard's kinematic chain model of human bimanual action. our results suggest that the guiard reference principle is robust with respect to variances in the kinesthetic reference frames as long as appropriate visual feedback is present.  ravin balakrishnan ken hinckley
an investigation of the roles of individual differences and user interface on database usability this research seeks to understand to what extent leveraging the graphical user interface's ability to convey spatial information can improve a user's ability to write effective database queries. this capability is believed to be especially important when nontechnical individuals, with diverse backgrounds and cognitive abilities, are expected to interact directly with these systems in the query formulation process.this study makes use of recent developments in graphical user interface technology to manipulate the level of spatial visualization support provided by the interface. a laboratory experiment was conducted to explore the influence of interface style and the spatial visualization ability of the user on the performance of the query development process. the application used in the experiment was a visual database query system developed for this study. one hundred sixty-two volunteers participated in the experiment. spatial visualization ability was assessed using a paper-folding test. the results indicate that both spatial visualization support of the system and spatial visualization ability of the user are important components of database usability. steven s. curl lorne olfman john w. satzinger
type hierarchies and semantic data models  the basic abstraction mechanisms of semantic data models - aggregation, classification and generalization - are considered the essential features to overcome the limitations of traditional data models in terms of semantic expressiveness. an important issue in database programming language design is which features should a programming language have to support the abstraction mechanisms of semantic data models. this paper shows that when using a strongly typed programming language, that language should support the notion of type hierarchies to achieve a full integration of semantic data models abstraction mechanisms within the language's type system. the solution is presented using the language galileo, a strongly typed, interactive programming language specifically designed for database applications.  antonio albano
functions in databases  we discuss the objectives of including functional dependencies in the definition of a relational database. we find two distinct objectives. the appearance of a dependency in the definition of a database indicates that the states of the database are to encode a function. a method based on the chase of calculating the function encoded by a particular state is given and compared to methods utilizing derivations of the dependency. a test for deciding whether the states of a schema may encode a nonempty function is presented as is a characterization of the class of schemas which are capable of encoding nonempty functions for all the dependencies in the definition. this class is the class of dependency preserving schemas as defined by beeri et al. and is strictly larger than the class presented by bernstein.  the second objective of including a functional dependency in the definition of a database is that the dependency be capable of constraining the states of the database; that is, capable of uncovering input errors made by the users. we show that this capability is weaker than the first objective; thus, even dependencies whose functions are everywhere empty may still act as constraints. bounds on the requirements for a dependency to act as a constraint are derived.  these results are founded on the notion of a weak instance for a database state, which replaces the universal relation instance assumption and is both intuitively and computationally more nearly acceptable.  marc h. graham
cautious transaction schedulers with admission control  we propose a new class of schedulers, called cautious schedulers, that grant an input request if it will not necessitate any rollback in the future. in particular, we investigate cautious wrw-schedulers that output schedules in class wrw only. class wrw consists of all schedules that are serializable, while preserving the write-read and read- write conflict, and is the largest polynomially recognizable subclass of serializable schedules currently known. it is shown, in this paper however, that cautious wrw-scheduling is, in general, np-complete. therefore, we introduce a special type (type 1r) of transaction, which consists of no more than one read step (an indivisible set of read operations) followed by multiple write steps. it is shown that cautious wrw-scheduling can be performed efficiently if all transactions are of type 1r and if admission control can be exercised. admission control rejects a transaction unless its first request is immediately grantable.  naoki katoh toshihide ibaraki tiko kameda
evaluation of signature files as set access facilities in oodbs  object-oriented database systems (oodbs) need efficient support for manipulation of complex objects. in particular, support of queries involving evaluations of set predicates is often required in handling complex objects. in this paper, we propose a scheme to apply signature file techniques, which were originally invented for text retrieval, to the support of set value accesses, and quantitatively evaluate their potential capabilities. two signature file organizations, the sequential signature file and the bit-sliced signature file, are considered and their performance is compared with that of the nested index for queries involving the set inclusion operator ( ). we develop a detailed cost model and present analytical results clarifying their retrieval, storage, and update costs. our analysis shows that the bit-sliced signature file is a very promising set access facility in oodbs.  yoshiharu ishikawa hiroyuki kitagawa nobuo ohbo
the onion technique: indexing for linear optimization queries  _this paper describes the onion technique, a special indexing structure for linear optimization queries. linear optimization queries ask for top-n records subject to the maximization or minimization of linearly weighted sum of record attribute values. such query appears in many applications employing linear models and is an effective way to summarize representative cases, such as the top-50 ranked colleges. the onion indexing is based on a geometric property of convex hull, which guarantees that the optimal value can always be found at one or more of its vertices. the onion indexing makes use of this property to construct convex hulls in layers with outer layers enclosing inner layers geometrically. a data record is indexed by its layer number or equivalently its depth in the layered convex hull. queries with linear weightings issued at run time are evaluated from the outmost layer inwards. we show experimentally that the onion indexing achieves orders of magnitude speedup against sequential linear scan when n is small compared to the cardinality of the set. the onion technique also enables progressive retrieval, which processes and returns ranked results in a progressive manner. furthermore, the proposed indexing can be extended into a hierarchical organization of data to accommodate both global and local queries._  yuan-chi chang lawrence bergman vittorio castelli chung-sheng li ming-ling lo john r. smith
minimum-drift digital video down-conversion  this paper presents a new technique for decoding a full-resolution video bitstream at low memory cost and displaying the signal at a lower resolution. existing techniques solve the problem by storing the down-converted blocks into memory instead of the full- resolution blocks. while the memory is reduced, these techniques introduce drift errors because the decoder does not have the same pixels as the encoder in performing motion-compensated prediction. the approach proposed here alleviates the problem by tracking the drift at the decoder. it improves the video quality without any increase in decoder complexity. the effectiveness of the approach is evaluated using both objective and subjective tests. this minimum-drift approach is very simple to implement and can also be applied for memory reduction of a full resolution hdtv decoder.  osama alshaykh homer chen
towards an information logic  'probability is expectation founded upon partial knowledge.' (boole, 1854)  information retrieval based on stored program electronic computers has been an active area of research since the time these machines were invented. it is therefore somewhat surprising that even now no formal computational model for ir exists. there is no well-defined logic to describe information retrieval, and there is no proof or model theory to talk about the truths of ir.  this paper argues that much of the research work in the past has been steps in the direction of a logic for ir. these steps have been taken by developing formal models for information retrieval, but to date none of these are complete nor could any claim to be a computational model for ir. to appreciate this development i shall present a picture of ir, describing bits of a puzzle which may fit together to point to a new framework within which a computational model or logic could be described.  c. j. van rijsbergen