ppxscal/embedding_network huggingface dataset:
Application of OODB and SGML techniques in text database: an electronic dictionary system
Authors: Jian Zhang
Venue: ACM SIGMOD Record (1995)

An electronic dictionary system (EDS) is developed with object-oriented database techniques based on ObjectStore. The EDS is composed of two parts: the Database Building Program (DBP), and the Database Querying Program (DQP). DBP reads in a dictionary encoded in SGML tags, and builds a database composed of a collection of trees which holds dictionary entries, and several lists which contain items of various lexical categories. With text exchangeability introduced by the SGML, DBP is able to accommodate dictionaries of different languages with different structures, after easy modification of a configuration file. The tree model, the Category Lists, and an optimization procedure enables DQP to quickly accomplish complicated queries, including context requirements, via simple SQL-like syntax and straightforward search methods. Results show that compared with relational database, DQP enjoys much higher speed and flexibility. With EDS this paper demonstrates how to apply OODBMS's to systems that handle text information with strong yet varied intrinsic hierarchies.
The meaning of negative premises in transition system specifications
Authors: Roland Bol, Jan Friso Groote
Venue: Journal of the ACM (JACM) (1996)

We present a general theory for the use of negative premises in the rules of Transition System Specifications (TSSs). We formulate a criterion that should be satisfied by a TSS in order to be meaningful, that is, to unequivocally define a transition relation. We also provide powerful techniques for proving that a TSS satisfies this criterion, meanwhile constructing this transition relation. Both the criterion and the techniques originate from logic programming [van Gelder et al. 1988; Gelfond and Lifschitz 1988] to which TSSs are close. In an appendix we provide an extensive comparison between them.As in Groote [1993], we show that the bisimulation relation induced by a TSS is a congruence, provided that it is in ntyft/ntyxt-format and can be proved meaningful using our techniques. We also considerably extend the conservativity theorems of Groote[1993] and Groote and Vaandrager [1992]. As a running example, we study the combined addition of priorities and abstraction to Basic Process Algebra (BPA). Under some reasonable conditions we show that this TSS is indeed meaningful, which could not be shown by other methods [Bloom et al. 1995; Groote 1993]. Finally, we provide a sound and complete axiomatization for this example.
Implementing data cubes efficiently
Authors: Venky Harinarayan, Anand Rajaraman, Jeffrey D. Ullman
Venue: ACM SIGMOD Record (1996)

Decision support applications involve complex queries on very large databases. Since response times should be small, query optimization is critical. Users typically view the data as multidimensional data cubes. Each cell of the data cube is a view consisting of an aggregation of interest, like total sales. The values of many of these cells are dependent on the values of other cells in the data cube. A common and powerful query optimization technique is to materialize some or all of these cells rather than compute them from raw data each time. Commercial systems differ mainly in their approach to materializing the data cube. In this paper, we investigate the issue of which cells (views) to materialize when it is too expensive to materialize all views. A lattice framework is used to express dependencies among views. We present greedy algorithms that work off this lattice and determine a good set of views to materialize. The greedy algorithm performs within a small constant factor of optimal under a variety of models. We then consider the most common case of the hypercube lattice and examine the choice of materialized views for hypercubes in detail, giving some good tradeoffs between the space used and the average time to answer a query.
Form Design for High Accuracy Optical Character Recognition
Authors: Michael D. Garris, Darrin L. Dimmick
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

To successfully apply character recognition technology most of the forms currently hand-keyed will need to be redesigned. This paper presents results from a comprehensive study of three versions of a redesigned tax form. Analyses show that using separately spaced character boxes provides superior machine readability over fields containing combs and adjoining character boxes. It is shown that character boxes containing two vertically stacked ovals cause writers much more difficulty. Analyses provide proof that writer idiosyncratic responses on forms are the major source of errors, and proper form design can reduce these errors.
Analysis and implementation of hybrid switching
Authors: Kang G. Shin, Stuart W. Daniel
Venue: Proceedings of the 22nd annual international symposium on Computer architecture (1995)

The switching scheme of a point-to-point network determines how packets flow through each node, and is a primary element in determining the network's performance. In this paper, we present and evaluate a new switching scheme called hybrid switching. Hybrid switching dynamically combines both virtual cut-through and wormhole switching to provide higher achievable throughput than wormhole alone, while significantly reducing the buffer space required at intermediate nodes when compared to virtual cut-through. This scheme is motivated by a comparison of virtual cut-through and wormhole switching through cycle-level simulations, and then evaluated using the same methods. To show the feasibility of hybrid switching, as well as to provide a common base for simulating and implementing a variety of switching schemes, we have designed SPIDER, a communication adapter built around a custom ASIC, the Programmable Routing Controller (PRC).
Counterexamples for Directed and Node Capacitated Cut-Trees
Authors: Andras A. Benczur
Venue: SIAM Journal on Computing (1995)

We show that there is no cut-tree for various connectivity concepts, hence pointing out to errors in the papers of Schnorr [SIAM J. Comput., 8 (1979), pp. 265-275] and Gusfield and Naor [Networks, 21 (1991), pp. 505-520]. Gomory and Hu [SIAM J. Appl. Math., 9 (1961), pp. 551-560] constructed a cut-tree for undirected graphs which compactly represents a minimum cut for each pair of vertices. This has a straightforward generalization to directed Eulerian graphs, cf. Gupta [SIAM J. Appl. Math., 15 (1967), pp. 168-171]. A generalization for arbitrary directed graphs was given by Schnorr. There is a well-known transformation of vetex connectivity to directed edge connectivity; directed edge cuts correspond to vertex cuts in some weak sense. The result of Schnorr was later applied by Gusfield and Naor [8] for such a cut-tree construction. In this paper counterexamples are described to show that for directed graphs there is no cut-tree and therefore the cut-tree results of Schnorr and Gusfield and Naor are incorrect. Our final example shows that, without weakening the notion of vertex connectivity, it is impossible to construct vertex cut-trees for undirected graphs in general.
Lower Bounds on Formula Size of Boolean Functions Using Hypergraph Entropy
Authors: Ilan Newman, Avi Wigderson
Venue: SIAM Journal on Discrete Mathematics (1995)

Korner defined the notion of graph entropy. He used it to simplify the proof of the Fredman--Komlos lower bound for the family size of perfect hash functions. We use this information-theoretic notion to obtain a general method for formula size lower bounds. This method can be applied to low-complexity functions for which the other known general methods do not apply.
On Feedback Equivalence of a Parameterized Familyof Nonlinear Systems
Authors: J.-B. Pomet, I. A. K. Kupka
Venue: SIAM Journal on Control and Optimization (1995)

The following question is considered for a smoothly parameterized family of control systems: Does there exist a smooth family of transformations (feedback only, feedback plus diffeomorphism, or feedback plus diffeomorphism with some restrictions on the parameter dependence of the diffeomorphism, called "matching conditions") changing the systems of the family into a single one? Some abstract necessary and sufficient conditions are given, under which an explicit construction of the transformation is proposed. Both local and global results are obtained. No constant rank assumption is needed for the general conditions, but they can be translated more explicitly under such assumptions.
An algebra approach to the deduction of data flow diagrams and object oriented diagrams from a set of specifications
Authors: Federico Vazquez
Venue: ACM SIGPLAN OOPS Messenger (1995)

The Software Engineering processes usually lack formal mathematical foundations. This paper presents a formal approach for the development of Specifications, Data Flow Diagrams and Object Oriented Diagrams using algebraic theory. The use of algebraic theory allows the check for completeness and consistency and the generation of automatic procedures for translating specifications into Data Flow Diagrams or Object Oriented Diagrams.
Unifying data and control transformations for distributed shared-memory machines
Authors: Michał Cierniak, Wei Li
Venue: Proceedings of the ACM SIGPLAN 1995 conference on Programming language design and implementation (1995)

We present a unified approach to locality optimization that employs both data and control transformations. Data transformations include changing the array layout in memory. Control transformations involve changing the execution order of programs. We have developed new techniques for compiler optimizations for distributed shared-memory machines, although the same techniques can be used for sequential machines with a memory hierarchy.Our compiler optimizations are based on an algebraic representation of data mappings and a new data locality model. We present a pure data transformation algorithm and an algorithm unifying data and control transformations. While there has been much work on control transformations, the opportunities for data transformations have been largely neglected. In fact, data transformations have the advantage of being applicable to programs that cannot be optimized with control transformations. The unified algorithm, which performs data and control transformations simultaneously, offers improvement over optimizations obtained by applying data and control transformations separately.The experimental results using a set of applications on a parallel machine show that the new optimizations improve performance significantly. These results are further analyzed using locality metrics with instrumentation and simulation.
An object-oriented model for a multimedia patient folder management system
Authors: Fernando Ferri, Domenico M. Pisanelli, Fabrizio L. Ricci
Venue: ACM SIGBIO Newsletter (1996)

The management of information related to clinical activities is a complex task. In fact, patient related information reported in patient folders comes from heterogeneous sources and may be rendered by means of different modalities. Data can originate from direct observations made by physicians like in the case of objective examination. In other cases physiologic phenomena are captured by means of the involved electrical activity (like in the case of heart or brain activity), whereas anatomical structure details are obtained by means of radiologic techniques. In this paper we propose an object-oriented model of a multimedia patient folder. This model has an adequate flexibility for adapting the most different clinical environment. It allows the physician to structure the information needed for his/her patient folder without employing a programming language. Finally we show some features of the CADMIO system, a tool for designing patient folder management systems, based on this model.
TCP and explicit congestion notification
Authors: Sally Floyd
Venue: ACM SIGCOMM Computer Communication Review (1994)

This paper discusses the use of Explicit Congestion Notification (ECN) mechanisms in the TCP/IP protocol. The first part proposes new guidelines for TCP's response to ECN mechanisms (e.g., Source Quench packets, ECN fields in packet headers). Next, using simulations, we explore the benefits and drawbacks of ECN in TCP/IP networks. Our simulations use RED gateways modified to set an ECN bit in the IP packet header as an indication of congestion, with Reno-style TCP modified to respond to ECN as well as to packet drops as indications of congestion. The simulations show that one advantage of ECN mechanisms is in avoiding unnecessary packet drops, and therefore avoiding unnecessary delay for packets from low-bandwidth delay-sensitive TCP connections. A second advantage of ECN mechanisms is in networks (generally LANs) where the effectiveness of TCP retransmit timers is limited by the coarse granularity of the TCP clock. The paper also discusses some implementation issues concerning specific ECN mechanisms in TCP/IP networks.
The Stochastic Maximum Principle for Linear, Convex Optimal Control with Random Coefficients
Authors: Abel Cadenillas, Ioannis Karatzas
Venue: SIAM Journal on Control and Optimization (1995)

This paper considers a stochastic control problem with linear dynamics, convex cost criterion, and convex state constraint, in which the control enters both the drift and diffusion coefficients. These coefficients are allowed to be random, and no $L^{p}$-bounds are imposed on the control. An explicit solution for the adjoint equation and a global stochastic maximum principle are obtained for this model. This is evidently the first version of the stochastic maximum principle that covers the consumption-investment problem. The mathematical tools are those of stochastic calculus and convex analysis. When it is assumed, as in other versions of the stochastic maximum principle, that the admissible controls are square-integrable, not only a necessary but also a sufficient condition for optimality is obtained. It is then shown that this particular case of the general model may be applied to solve a variety of problems in stochastic control, including the linear-regulator, predicted-miss, and Benes problems.
Models for supporting the redesign of organizational work
Authors: Eric S. K. Yu
Venue: Proceedings of conference on Organizational computing systems (1995)

Many types of models have been proposed for supporting organizational work. In this paper, we consider models that are used for supporting the redesign of organizational work. These models are used to help discover opportunities for improvements in organizations, introducing information technologies where appropriate. To support the redesign of organizational work, models are needed for describing work configurations, and for identifying issues, exploring alternatives, and evaluating them. Several approaches are presented and compared. The i* framework &mdash; consisting of the Strategic Dependency and Strategic Rationale models &mdash; is discussed in some detail, as it is expressly designed for modelling and redesigning organizational work. We argue that models which view organizational participants as intentional actors with motivations and intents, and abilities and commitments, are needed to provide richer representations of organizational work to support its effective redesign. The redesign of a bank loan operation is used as illustration.
A reuse approach based on object orientation: its contributions in the development of CASE tools
Authors: Henda Hadjami Ben Ghezala, Farouk Kamoun
Venue: ACM SIGSOFT Software Engineering Notes (1995)

The aim of this paper is to present an approach to facilitate reuse. This approach, which is based on an object oriented design method, describes a way of structuring components and reuse library.Two concepts, domain and theme, are introduced to allow a classification of components by the services that they offer and by application domain. The library itself is organized in three hierarchical levels -general, dedicated and personal-, where the reusable components are stored according to their degree of &ldquo;interest&rdquo; (general interest, by application type or particular). So, the library is generic and could cluster various reusable component types (specification components, design components, packages,&hellip;).The contributions of this approach in the development of CASE tools are also emphasized.
In school or out: technology, equity, and the future of our kids
Authors: Saul Rockman
Venue: Communications of the ACM (1995)

In January, Newt Gingrich proposed a tax credit for the poorest Americans to purchase laptop computers, forgetting for the moment that the poorest Americans do not pay taxes and thus a credit does them no good. In this case, his heart may be in the right place, even if he later called the idea &ldquo;nutty.&rdquo;
Function From Motion
Authors: Zoran Duric, Jeffrey A. Fayman, Ehud Rivlin
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

In order for a robot to operate autonomously in its environment, it must be able to perceive its environment and take actions based on these perceptions. Recognizing the functionalities of objects is an important component of this ability. In this paper, we look into a new area of functionality recognition: determining the function of an object from its motion. Given a sequence of images of a known object performing some function, we attempt to determine what that function is. We show that the motion of an object, when combined with information about the object and its normal uses, provides us with strong constraints on possible functions that the object might be performing.
The ALOHA System
Authors: F. F. Kuo
Venue: ACM SIGCOMM Computer Communication Review (1995)

THE ALOHA SYSTEM is composed of a related series of contracts and grants from a variety of funding agencies with principal support from ARPA, which deal with two main themes: computer communications (TASK 1), and computer structures (TASK 2).Under computer-communications there is work in (a) Studies on computer communications using radio and satellites, (b) The development of a prototype radio-linked time-sharing network, (c) System studies and planning for a Pacific area computer communications network linking major universities in the U.S., Japan, Australia and other Pacific countries.Under computer structures, we are engaged in research/development in multiprocessor computing structures, computer networks, and geographically distributed computing systems. This work is being undertaken in two phases: 1) the establishment of a research facility and 2) the research work itself. The research facility is centered around the BCC 500 computing system.
Comparative analysis of periodic state saving techniques in time warp simulators
Authors: Josef Fleischmann, Philip A. Wilsey
Venue: Proceedings of the ninth workshop on Parallel and distributed simulation (1995)

Checkpointing in a time warp synchronized parallel simulator is a necessary and potentially expensive operation. In the simple case, a time warp simulator checkpoints every &khgr; events, for some fixed value &khgr;. For larger values of &khgr;, the simulator requires less overhead for saving the state, but incurs an increased latency during rollback. Thus, the problem is to balance the time to save states against the time to coast forward upon rollback. Unfortunately, a static determination of a optimal value for &khgr; is very difficult and can vary widely, even between closely related instances of a time warp simulator. Furthermore, the optimal checkpoint interval may actually vary over the lifetime of the simulation.To address these problems, several investigators have proposed dynamically adjusting the checkpoint interval &khgr; as the simulation progresses. This paper analyzes three previous techniques for dynamically sizing checkpoint intervals and presents a new, heuristic algorithm for this purpose. All four techniques are implemented in a common application domain (digital system simulation from VHDL descriptions) and a direct comparison between the algorithms is performed. The results show a significant difference in the performance of the implemented algorithms. However, in virtually all cases, the dynamic algorithms performed near or better than the best static value. Furthermore, the best algorithms performed as much as 12% better than the best static value.
Computational geometry
Authors: Joseph O'Rourke
Venue: ACM SIGACT News (1995)

The recent breakthrough of Halperin and Sharir on the complexity of lower envelopes of surfaces is described.
Translating collocations for bilingual lexicons: a statistical approach
Authors: Frank Smadja, Kathleen R. McKeown, Vasileios Hatzivassiloglou
Venue: Computational Linguistics (1996)

Collocations are notoriously difficult for non-native speakers to translate, primarily because they are opaque and cannot be translated on a word-by-word basis. We describe a program named Champollion which, given a pair of parallel corpora in two different languages and a list of collocations in one of them, automatically produces their translations. Our goal is to provide a tool for compiling bilingual lexical information above the word level in multiple languages, for different domains. The algorithm we use is based on statistical methods and produces p-word translations of n-word collocations in which n and p need not be the same. For example, Champollion translates make...decision, employment equity, and stock market into prendre...d&eacute;cision, &eacute;quit&eacute; en mati&egrave;re d'emploi, and bourse respectively. Testing Champollion on three years' worth of the Hansards corpus yielded the French translations of 300 collocations for each year, evaluated at 73% accuracy on average. In this paper, we describe the statistical measures used, the algorithm, and the implementation of Champollion, presenting our results and evaluation.
Structure Learning of Bayesian Networks by Genetic Algorithms: A Performance Analysis of Control Parameters
Authors: Pedro Larrañaga, Mikel Poza, Yosu Yurramendi, Roberto H. Murga, Cindy M. H. Kuijpers
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

We present a new approach to structure learning in the field of Bayesian networks: We tackle the problem of the search for the best Bayesian network structure, given a database of cases, using the genetic algorithm philosophy for searching among alternative structures. We start by assuming an ordering between the nodes of the network structures. This assumption is necessary to guarantee that the networks that are created by the genetic algorithms are legal Bayesian network structures. Next, we release the ordering assumption by using a "repair operator" which converts illegal structures into legal ones. We present empirical results and analyze them statistically. The best results are obtained with an elitist genetic algorithm that contains a local optimizer.
PROMIS: a software metrics tool generator
Authors: Peter Kokol, Viljem Žumer, Janez Brest, Marjan Mernik
Venue: ACM SIGPLAN Notices (1995)

The application of measurement technology in software engineering was not recognised enough in last decades, but recent trends show that software metrics are becoming more and more important. Indeed the development and use of adequate measurement of software and its design process are essential to the production of cost-effective and quality software. Actually, software metrics are not only significant as analysis instruments, but regarding the present iterative software design paradigms, they are likewise becoming powerful synthesis mechanisms. The main objective of this paper is to show that modern software tools and especially compiler-compilers, metric life cycle model and fractal metrics can improve the situation and make the development and use of software metrics more efficient and effective.