ppxscal/embedding_network huggingface dataset:
Verso la costruzione di un soggettario per il Progetto BIBLOS all''Istituto di Linguistica Computazionale
Authors: Gabriella Pardelli
Venue:  (1998)

This document describes a methodology aimed at building a subject catalogue at the Institute for Computational Linguistics within the framework of the Biblos Project (Virtual Humanities Library of the National Research Council). TEL:: +39 50 560481 The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
PRO-ART: Enabling Requirements Pre-Traceability
Authors: Klaus Pohl
Venue: Proceedings of the 2nd International Conference on Requirements Engineering (ICRE '96) (1996)

Requirements traceability is essential for developing software systems of high quality. Whereas the traceability of the refinement, deployment, and use of a requirement is called post-traceability, the traceability of a requirement back to its origin is named pre-traceability. In this contribution we present a requirements engineering environment, called PRO-ARTProcess and RepOsitory based Approach for Requirements Traceability, which enables requirements pre-traceability. PRO-ART is based on three main contributions: a three-dimensional framework for requirements engineering which defines the kind of information to be recorded; a trace-repository for structuring the trace information and enabling selective trace retrieval; a novel tool interoperability approach which enables (almost) automated trace capture. In addition, we report on experiences made with the first prototypical implementation of PRO-ART and the resulting re-design and re-implementation, called PRO-ART 2.0, which mainly addresses scalability problems faced with in real applications.
A Review of Experiences with Reliable Multicast
Authors: Kenneth Birman
Venue:  (1999)

By understanding how real users have employed reliable multicast in real distributed systems, we can develop insight concerning the degree to which this technology has matched expectations. This paper reviews a number of applications with that goal in mind. Our findings point to tradeoffs between the form of reliability used by a system and its scalability and performance. We also find that to reach a broad user community (and a commercially interesting market) the technology must be better integrated with component and object-oriented systems architectures. Looking closely at these architectures, however, we identify some assumptions about failure handling which make reliable multicast difficult to exploit. Indeed, the major failures of reliable multicast are associated with attempts to position it within object oriented systems in ways that focus on transparent recovery from server failures. The broader opportunity appears to involve relatively visible embeddings of these tools into object-oriented architectures enabling knowledgeable users to make tradeoffs. Fault-tolerance through transparent server replication may be better viewed as an unachievable holy grail. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Region Synchronization in Message Passing Systems
Authors: Gurdip Singh, Ye Su
Venue: Proceedings of the 2002 International Conference on Parallel Processing (2002)

The development of correct synchronization code for distributed programs is a challenging task. In this paper, we propose an aspect oriented technique for developing synchronizationcode for message passing systems. Our approach is to factor out synchronization as a separate aspect, synthesize synchronization code and then compose it with the functional code. Specifically, we allow the designer of an application to first design the functional code. The designer can then annotate the functional code with regions and specify a high-level "global invariant" specifying the synchronization policy. A synchronization policy essentiallygives the occupancy rules for the various regions. The solution to this problem, which we term the region synchronization problem, involves deriving a set of rules for entering and exiting each region. We provide a systematic the invariant into a message passing algorithm for a point-to-point message passing system. We show that many existing synchronization problems such as group mutual exclusion, reader/writers, committee coordination, and barrier can bespecified as instances of the region synchronization problem. Hence, our algorithms can be used to solve a large class of synchronization problems.
Bit-optimal decoding of codes whose Tanner graphs are trees
Authors: E. Soljanin, E. Offer
Venue: Discrete Applied Mathematics (2003)

We introduce a group algebra formulation for bit-optimal decoding of binary block codes. We use this new framework to give a simple algebraic proof that Pearl's and Gallager's belief propagation decoding algorithms are bit-optimal when the Tanner graph of the code is a tree. We believe that these derivations of known results give new insights into the issues of decoding on graphs from the algebraic coding theorist's point of view.
The efficient computation of sparse Jacobian matrices using automatic differentiation
Authors: Thomas F. Coleman, Arun Verma
Venue:  (1995)

This paper is concerned with the efficient computation of sparse Jacobian matrices of nonlinear vector maps using automatic differentiation (AD). Specifically, we propose the use of a graph coloring technique, bi-coloring, to exploit the sparsity of the Jacobian matrix $J$ and thereby allow for the efficient determination of $J$ using AD software. We analyze both a direct scheme and a substitution process. We discuss the results of numerical experiments indicating significant practical potential of this approach.
Democracy and the Internet: Allies or Adversaries?
Authors: Leslie David Simon, Javier Corrales, Donald R. Wolfensberger
Venue:  (2002)

:Is the internet intrinsically democratic, making every user a publisher and supporting new varieties of expression and association? Or is it a dangerous vehicle of propaganda, helping repressive governments to deceive their people and mobs to drive democratic governments to extremes? In Democracy and the Internet: Allies or Adversaries? three essays draw evidence from starkly different regions of the world. Leslie David Simon turns to one of the world's least democratic regions, the Muslim nations of the Middle East; Javier Corrales reviews the weak democracies of Latin America, and Donald R. Wolfensberger studies the world's most visible representative institution, the U.S. Congress. The authors find that the internet is generally making a positive difference. In some places people are newly receiving important outside news and communications. In others, human rights organizations and banned newspapers can make their cases online for both domestic and international audiences. Use by extremist groups has caused little damage compared to the benefits. The chief hangup is limited availability, either because the market is too weak to spread technology without government support or because repressive states are restricting access. At Congress, the internet was crucial in preserving operations when the post-September 11 anthrax attack shut down Capitol Hill, and more opportunities exist, but there is also the danger of overload. About the Author:Leslie David Simon is the author of NetPolicy.Com: Public Agenda for a Digital World. A former IBM executive, he is a senior policy scholar at the Woodrow Wilson International Center for Scholars. Javier Corrales is aprofessor of political science at Amherst College and a former fellow at the Woodrow Wilson Center. Donald R. Wolfensberger is director of the Congress Project at the Center; a longtime Congressional staffer, he is the author of Congress and the People: Deliberative Democracy on Trial.
Domain Decomposition Methods for Conformal Mapping and Eigenvalue Problems
Authors: Tobin A Driscoll
Venue:  (1996)

Domain decomposition is widely used in the numerical solution of elliptic boundary value problems. It is appealing in part because of improved efficiency and straightforward parallelization. Conceptually, domain decomposition often exploits a natural feature of elliptic problems: data at one point may have an exceedingly weak influence on the solution at a far-removed point. The application of domain decomposition to other elliptic problems is less fully developed. One such area is numerical conformal mapping. We introduce the SC Toolbox for Matlab, an interactive graphical software package for the Schwarz-Christoffel mapping of polygons. The Toolbox can be used for interior and exterior mapping from several fundamental domains. Elongations in the polygon lead to crowding, in which the preimages of affected vertices are exponentially close together. Such regions are candidates for decomposition. We describe CRDT, an overlapping subdomain method developed with Vavasis for numerical Schwarz-Christoffel mapping. The method uses Delaunay triangulation to decompose the polygon into overlapping quadrilaterals, which in turn define cross-ratios that form the basis of a nonlinear system. Each quadrilateral induces an embedding of the prevertices so that locally, the map can be computed accurately. Apparently CRDT can deal with any degree of crowding, as is demonstrated by examples. Another application in conformal mapping is in Symm''s integral equation. An important feature of existing software for Symm''s equation is the efficient treatment of corner singularities. Careful generalization to multiple domains allows this treatment to be preserved and extended. A nonoverlapping formulation leads to a linear system that is ideal for Schur complementation. The resulting method asymptotically requires a fraction of the single-domain work and is easily parallelized. We also consider a domain decomposition algorithm for the Laplace eigenvalue problem on polygons. This method, an improvement on one described by Descloux and Tolley, searches for the matching of Fourier-Bessel expansions at each corner to locate eigenvalues. We apply the algorithm to the "isospectral drums" discovered by Gordon, Webb, and Wolpert to find 25 eigenvalues to 12 digits. The method is far more accurate and efficient than standard methods for this problem.
Rapid system understanding: two COBOL case studies
Authors: Arie Deursen, T. Kuipers
Venue:  (1998)

Rapid system understanding is required in the planning, feasibility assessment and cost estimating phases of a system renovation project. In this paper, we apply a number of analyses on two large legacy COBOL systems from the banking field. We describe the analyses performed, and discuss possible interpretations of these analyses. Lessons learned include: (1) The open architecture adopted is satisfactory, and can take advantage of a wide range of understanding tools available; and (2) To handle inter-system variability effectively, the flexibility of lexical analysis is required.
Prevention is Better than Cure
Authors: Mira Kajko-Mattsson, Gunnar Björkman, Ingegerd Nyamesah, Anna Sors, Per-Erik Lundh
Venue: Proceedings of the International Conference on Software Maintenance (ICSM'00) (2000)

Was all the mania leading up to the turn of the millennium warranted or was it just a load of computer maintenance ballyhoo designed to attract attention? In this paper, we spot test a selected number of Swedish companies to establish their state of preparedness just before meeting the new millennium as well as the effects they have encountered immediately after the turn of the millennium. These are then compared to the list of effects compiled by the Millennium Commission (appointed by the Swedish Government).
Algorithms in Java, Part 5: Graph Algorithms, 3 edition
Authors: Robert Sedgewick, Michael Schidlowsky
Venue:  (2003)

:Once again, Robert Sedgewick provides a current and comprehensive introduction to important algorithms. The focus this time is on graph algorithms, which are increasingly critical for a wide range of applications, such as network connectivity, circuit design, scheduling, transaction processing, and resource allocation. In this book, Sedgewick offers the same successful blend of theory and practice that has made his work popular with programmers for many years. Michael Schidlowsky and Sedgewick have developed concise new Java implementations that both express the methods in a natural and direct manner and also can be used in real applications.Algorithms in Java, Third Edition, Part 5: Graph Algorithms is the second book in Sedgewick's thoroughly revised and rewritten series. The first book, Parts 1-4, addresses fundamental algorithms, data structures, sorting, and searching. A forthcoming third book will focus on strings, geometry, and a range of advanced algorithms. Each book's expanded coverage features new algorithms and implementations, enhanced descriptions and diagrams, and a wealth of new exercises for polishing skills. The natural match between Java classes and abstract data type (ADT) implementations makes the code more broadly useful and relevant for the modern object-oriented programming environment.
Transfer of data over ATM networks using available bit rate (ABR)
Authors: G. E. Konstantoulakis, G. I. Stassinopoulos
Venue: Proceedings of the IEEE Symposium on Computers and Communications (ISCC'95) (1995)

The paper contributes to currently debated key issues on the evolution of ATM networks and their standardisation. It takes the view that since the asynchronous transfer mode has features of both circuit and packet switching, one has to selectively draw benefits for different types of traffic, compromising, if necessary, the integration principle. The use of the available bit rate (ABR), promoted by the ATM Forum for handling time insensitive (best effort) traffic, is fully adopted and its influence on switching discussed in detail. Coupled with ABR for transmission, the paper supports the employment of massive memory within the switching equipment. By suggesting solutions to key memory management problems, it also examines the use of X.25-like flow and congestion control, selectively employed for data transfer over ATM networks.
A time-evolving data structure scalable between discrete and continuous attribute modifications
Authors: Martin Danielsson, Rainer Müller
Venue: Computer Science in Perspective: Essays Dedicated to Thomas Ottmann (2003)

Time-evolving data structures deal with the temporal development of object sets describing in turn some kind of real-world phenomena. In the bitemporal case also objects having counterparts with an own predefined temporal component can be modelled. In this paper, we consider a subset of the problems usually covered by this context, having many real applications in which certain real-time constraints have to be met: synchronizability and random real-time access. We present a solution called the relational approach, which is based on a generalization of interval objects. By comparing this approach with the original simple transaction-based solution, we show its free scalability in the length of these interval objects, reducing the redundancy, in data representation to a minimum.
Precluding Useless Events for On-Line Global Predicate Detections
Authors: Li-Hsing Yen
Venue: Proceedings of the The 20th International Conference on Distributed Computing Systems ( ICDCS 2000) (2000)

Detecting global predicates is an important task in testing and debugging distributed programs. In this paper, we propose an approach that effectively precludes useless events for global predicate detection, facilitating the process of an independent on-line checking routine. To identify more useless events than a simple causality-check method can do, our method tracks and maintains the precedence information of event intervals as a graph.To reduce the potentially expensive space and time cost as the graph expands, we propose an effective scheme to prune the graph. The performance of our method is analyzed and evaluated by simulations. The result shows that our approach outperforms conventional approaches in terms of the number of useless events found.
A Notation for Lambda Terms II: Refinements and Applications
Authors: Gopalan Nadathur, Sue D Wilson
Venue:  (1994)

Issues that are relevant to the representation of lambda terms in contexts where their intensions have to be manipulated are examined. The basis for such a representation is provided by the suspension notation for lambda terms that is described in a companion paper. This notation obviates $\alpha$-conversion in the comparison of terms by using the `nameless'' scheme of de Bruijn and also permits a delaying of substitutions by including a class of terms that encode other terms together with substitutions to be performed on them. The suspension notation contains a mechanism for `merging'' substitutions so that they can be effected in a common structure traversal. The mechanism is cumbersome to implement in its full generality and a simplification to it is considered. In particular, the old merging operations are eliminated in favor of new ones that capture some of their functionality and that permit a simplified syntax for terms. The resulting notation is refined by the addition of annotations to terms that serve to indicate whether or not they can be affected by substitutions generated by external $\beta$-contractions. These annotations permit substitutions to be performed trivially in certain situations, and can consequently lead to a conservation of space and time in a graph-based implementation of reduction. The use of the refined notation in the comparison of terms is then examined. The notion of head normal forms is generalized to its context and shown to be useful in checking terms for equality and a graph-based procedure for finding head normal forms is presented. This procedure is accompanied by a complete proof of its correctness and the tools of analysis afforded by our notation are used in this process. The relevance of the considerations here to an ongoing implementation of the language $\lambda$Prolog is discussed.
Ring beam stiffness effect on behaviour of reticulated timber domes
Authors: D. H. Pan, U. A. Girhammar
Venue: Proceedings of the sixth conference on Computational structures technology (2002)

In this paper, reticulated timber domes of triangular network shape with decking and bottom tension ring are considered. The dome is subjected to evenly distributed load over entire dome. The dome model is generated by a preprocessor program DOMEIN and analysed by ABAQUS. The behaviour with respect to different stiffnesses of the bottom ring beam is evaluated. A design parameter for the ring beam is introduced (Ar*). It is shown that the non-dimensional area parameter should exceed Ar* > 20 in order to obtain optimum values for the buckling load, maximum deflection, normal forces and bending moments.
Performance evaluations of a MetaRing MAC protocol integrating video and data traffics in an interconnected environment
Authors: G. Anastasi, L. Lenzini, P. Motta
Venue: Proceedings of the Fourteenth Annual Joint Conference of the IEEE Computer and Communication Societies (Vol. 3)-Volume - Volume 3 (1995)

The MetaRing is a medium access control (MAC) protocol for LANs and MANs operating at a speed of 1 Gbit/sec and above. The MetaRing MAC protocol offers its users synchronous and asynchronous types of services and can operate under two basic access control modes: buffer insertion for variable size packets, and slotted for fixed length cells. The latter mode of operation is considered in this paper. In the first part of the paper an analysis of the asynchronous type of service is performed. The analysis has been carried out on a network configuration (hereafter called scenario) which, other than being realistic, is particularly critical with respect to slot reuse. It consists of a group of equally spaced nodes sending asynchronous traffic to a gateway interconnecting the MetaRing with other communication subnetworks. Results obtained show that the MetaRing is unfair and that the unfairness depends, in particular, upon the offered load, besides the K and L protocol parameter values. In the second part of the paper we focus on the study of the traffic integration capability provided by the MetaRing MAC protocol. The results provide a strong indication that the MetaRing MAC protocol is suitable for VBR video and data traffic integrations.
Shared Tree Wireless Network Multicast
Authors: Ching-Chuan Chiang, Mario Gerla, Lixia Zhang
Venue: Proceedings of the 6th International Conference on Computer Communications and Networks (1997)

In this paper, we propose a multicast protocol for a multihop, mobile wireless network with cluster based routing and token access protocol within each cluster. The multicast protocol uses a shared tree which is dynamically updated to adjust to changes in topology and membership (i.e. dynamic joins and quits). Two options for tree maintenance have been simulated and evaluated: "hard state" (i.e. each connection must be explicitly cleared) and "soft state" (each connection is automatically timed out and must be refreshed). For the soft state policy, the performance of different choices of timeout and refresh timers is first analyzed for a range of node mobility values. Next, soft state and hard state policies are compared based on throughput, join delay, and control overhead criteria.
An asset view on the software process
Authors: R. M. Greenwood, P. Kawalek, L. Robertson, B. C. Warboys
Venue: Proceedings of the 10th International Software Process Workshop (1996)

There are issues of concern to software engineers that cannot be addressed in the context of a single development project. This paper indicates some typical issues, and proposes an asset view of the software development process to enable them to be considered. The asset view places less emphasis on the temporal ordering of activities and more on the concepts of goals, interactions, learning and evolution. It is complementary to the more conventional production view. The asset view may be a better starting point for considerations of reuse and product lines.
About Adaptive State Knowledge Extraction for Septic Shock Mortality Prediction
Authors: Rüdiger W. Brause
Venue: Proceedings of the 14th IEEE International Conference on Tools with Artificial Intelligence (2002)

The early prediction of mortality is one of the unresolved tasks in intensive care medicine. This contribution models medical symptoms as observations cased by transitions between hidden markov states. Learning the underlying state transition probabilities results in a prediction probability success of about 91%.The results are discussed and put in relation to the model used. Finally, the rationales for using the model are reflected: Are there states in the septic shock data?