ppxscal/embedding_network huggingface dataset:
Performance impact of partial reconfigurability in lightwave networks
Authors: Jean-François Labourdette
Venue: Proceedings of the Fourteenth Annual Joint Conference of the IEEE Computer and Communication Societies (Vol. 2)-Volume - Volume 2 (1995)

Rearrangeable multihop lightwave networks can be dynamically reconfigured to adapt the connectivity among network stations to prevailing traffic conditions. Most of the literature has analyzed the performance of such networks assuming no limitations on the range of tunability of the transmitters and/or receivers allocated to each network station. Therefore, all connection diagrams could be realized among network stations, within the constraints of the number of transmitters and receivers at each station. Since the number of wavelengths in use may be very large, a practical implementation would restrict the tunability range of each transmitter and receiver to some limited set of contiguous wavelengths, or waveband. However, there is a penalty associated with such restrictions in that all connection diagrams might not be achievable and the network performances could degrade. The author derives lower bounds on the performance degradation experienced by the network when there are tunability limitations. He then proposes and analyzes a waveband assignment and grouping scheme, illustrating that one can design networks with good performance even though there are tunability constraints on the transceivers. He also describes other architectures (multi-fiber physical topology, subcarrier division multiplexing) for which the model and analysis readily apply.
A Case-Analysis Approach to Disjunctive Logic Programming
Authors: W D Reed
Venue:  (1992)

Disjunctive Logic programming is an extension of standard Horn logic programming which allows for the expression of indefinite or incomplete information. In this thesis, we provide a unified approach to disjunctive logic programming based on case-analysis. We describe a family of procedures, called the near-Horn Prologs, which naturally extend the standard Horn program procedure (SLD-resolution) through case-analysis. Since the near-Horn Prolog procedures retain much of the form and flavor of SLD-resolution (the basis of the programming language Prolog), they may be seen as the ideal basis for a programming language which extends Prolog. The near-Horn Prolog procedures also appear to be more efficient than alternative procedures (such as SLI-resolution), especially when the amount of non-Horn information in a program is small. We provide the theoretical foundations of the near-Horn Prologs with a declarative characterization of disjunctive logic programs which utilizes fixpoint operators. In addition to capturing the consequences of a program (while naturally extending the standard Horn program characterization), this characterization matches the case-analysis behavior of one of the near-Horn Prolog variants and so provides insight into its behavior. We consider the addition of negation to disjunctive logic programs, demonstrating that both explicit classical negation and implicit default negation can easily be incorporated into our case-analysis approach. We also compare the near-Horn Prologs with proof systems taken from varied application domains, and show that each utilizes case-analysis in a similar manner. By comparing these different systems, we gain insight into the approach and the relative tradeoffs involved.
Bridging Program Comprehension Tools by Design Navigation
Authors: Sébastien Robitaille, Reinhard Schauer, Rudolf K. Keller
Venue: Proceedings of the International Conference on Software Maintenance (ICSM'00) (2000)

Source code investigation is one of the most time consuming activities during software maintenance and evolution, yet currently available tool support suffers from several shortcomings. Browsing is typically limited to low-level elements, investigation is only supported as a one-way activity, and tools provide little help in getting an encompassing picture of the system under examination. In our research, we have developed tool support for design navigation that addresses these shortcomings. A Design Browser allows for flexible browsing of a system's design level representation and for information exchange with a suite of program comprehension tools. The browser is complemented with a Retriever supporting full-text and structural searching. In this paper, we detail these tools and their integration into a reverse engineering environment, present three case studies, and put them into perspective.
Load Balancing in Distributed Web Server Systems with Partial Document Replication
Authors: Ling Zhuo, Cho-Li Wang, Francis C. M. Lau
Venue: Proceedings of the 2002 International Conference on Parallel Processing (2002)

How documents of a web site are replicated and where they are placed among the server nodes have an important bearing on balance of load in a geographically Distributed Web Server (DWS) system. The traffic generated due to movements of documents at runtime could also affect the performance of the DWS system. In this paper, we prove that minimizing such traffic is NP-hard. We propose a new document distribution scheme that periodically performs partial replication of a site's documents at selected server locations to maintain load balancing. Several approximation algorithms are used in it to minimize traffic generated. The simulation results show that this scheme can achieve better load balancing than a dynamic scheme, while the internal traffic it causes has a negligible effect on the system's performance.
An Implementation of Object-Oriented Program Transformation for Thought-Guided Debugging
Authors: Tiffany M. Wong
Venue:  (2001)

This paper presents our design and implementation of program transformation for C++ that will be used in the context of a thought-guided debugging system. The program uses a lexical analyzer written in Flex and a grammar written in Bison that work in conjunction to scan the inputted C++ code for function definitions and class definitions. The code is then transformed to produce trace information for each defined function, while the original functionality of the code is left untouched. We also implement two additional data structures that are used for information storage during the course of the program. 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
Opening Night at Upson Hall (Scripts from Holiday Party Skits)
Authors: A. Non Ymous
Venue:  (1982)

Every holiday season comes the time when the thoughts of graduate students at Cornell turn to the fast-approaching A-exams. More precisely, they think, "We''d better get them before they get us.". Hence, these attempts at theatrical productions. Although they are based on the quirks and idiosyncracies of faculty members, they should not be taken as criticism. The authors would prefer to think that everyone is laughing together, rather than at anyone in particular. And with this word of caution, we present... 1977, 1978, 1979, 1980, 1981. 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
Corner Detection in Textured Color Images
Authors: Mark A. Ruzon, Carlo Tomasi
Venue: Proceedings of the International Conference on Computer Vision-Volume 2 - Volume 2 (1999)

Corner models in the literature have lagged behind edge models with respect to color and shading. We use both a region model, based on distributions of pixel colors, and an edge model, which removes false positives, to perform corner detection on color images whose regions contain texture. We show results on a variety of natural images at different scales that highlight the problems that occur when boundaries between regions have curvature.
Performance analysis of traffic control methods in multimedia ATM LAN
Authors: N. Wakamiya, K. Baba, M. Murata, H. Miyahara
Venue: Proceedings of the Fourteenth Annual Joint Conference of the IEEE Computer and Communication Societies (Vol. 3)-Volume - Volume 3 (1995)

The authors treat traffic control methods suitable to ATM LAN, in which two service classes are considered; one is for high speed data transfer based on a fast reservation protocol (FRP service class) and the other is for continuous bit rate (CBR) traffic such as motion video (CBR service class). The authors first evaluate the performance of the FRP service class. When the terminal requests the data transfer, its usable bandwidth is negotiated with the traffic descriptor (C/sub max/, C/sub min/) The former is a desirable data transfer rate, and the latter is a sustainable rate when the network is congested. By carrying out a mathematical analysis, the authors show an appropriate set of the traffic descriptor. The coexistence of FRP and CBR service classes are then treated. By using an analytic method, the performance of the CBR service class traffic is shown to be heavily affected by the FRP service class traffic. Therefore, the authors introduce a reserved bandwidth to the CBR service class to guarantee some appropriate level of performance to the CBR service class.
Graphical Animation of Parallel Fortran Programs
Authors: Sue Utter, Cherri M. Pancake
Venue:  (1991)

A tool for visualizing the behavior of parallel Fortran programs is described. PF-View builds on the functionality already provided by IBM''s Parallel Fortran Trace Facility, extending its usefulness by postprocessing the textual trace information to derive a graphical framework on which program behavior is animated. Its design capitalizes on formal and informal studies of how programmers go about parallelizing scientific applications, providing an intuitive representation of program execution. Detailed information on lock/event synchronization and performance analysis, while quickly available through additional windows, is hidden from the casual user to maximize ease and simplicity. Most importantly, the program as the user knows it--in the form of hierarchiacally-organized source code--is constantly available and automatically correlated with the animation to underscore visually the relationship between source statements and run-time actions.
Towards automated verification of Splice in muCRL
Authors: Paul F.G. Dechering, Izak A. Langevelde
Venue:  (2000)

A considerable fragment of the coordination architecture {\sc Splice}, including \Ethernet, is specified in the process-algebraic language {$\mu${\sc crl}. This specification is used to generate transition systems for a number of simple {\sc Splice} applications which are verified by model checking using the {\sc C{\ae}sar/Ald\''{e}baran} tool set. For these cases the properties of deadlock freeness, soundness and weak completeness are proven. The primary result reported is a detailed formal model of {\sc Splice} that makes possible automated verification. In practice, however, it is only for very simple {\sc Splice} applications feasible to generate a transition system. Nevertheless, model checking applied to a large number of small applications, or scenarios, can be used to gather evidence for the validity of properties that is more general than testing in that it considers all possible system traces for a given scenario instead of just one trace. For applications with a high degree of non-determinism this can be an interesting advantage.
Multicomponent, Multiphase Thermodynamicsof Swelling Porous Media with Electroquasistatics:I. Macroscale Field Equations
Authors: Lynn S Bennethum, John H. Cushman
Venue:  (1999)

In this paper we systematically develop macroscopic field equations (conservation of mass, linear and angular momentum, energy, and Maxwell''s equations) for a multiphase, multicomponent medium. It is assumed that speeds involved are much slower than the speed of light and that the magnitude of the electric field dominates significantly over the magnetic field so that the electroquasistatic form of Maxwell''s equations apply. We begin with a mixture formulation for each phase and average these equations to obtain the macroscopic formulation. The relationship between species and bulk phase variables and the macroscopic and microscopic variables are given explicitly. The resulting field equations are required for many practical applications including, but not limited to, swelling clays (smectites), biopolymers, biological membranes, pulsed electrophoresis, and chromotography.
The Hamilton-Jacobi Skeleton
Authors: Kaleem Siddiqi, Sylvain Bouix, Allen Tannenbaum, Steven W. Zucker
Venue: Proceedings of the International Conference on Computer Vision-Volume 2 - Volume 2 (1999)

The eikonal equation and variants of it are of significant interest for problems in computer vision and image processing. It is the basis for continuous versions of mathematical morphology, stereo, shape-from-shading and for recent dynamic theories of shape. Its numerical simulation can be delicate, owing to the formation of singularities in the evolving front, and is typically based on level set methods. However, there are more classical approaches rooted in Hamiltonian physics, which have received little consideration in computer vision.In this paper we first introduce a new algorithm for simulating the eikonal equation, which offers a number of computational and conceptual advantages over the earlier methods when it comes to shock tracking. Next, we introduce a very efficient algorithm for shock detection, where the key idea is to measure the net outward flux of a vector field per unit volume, and to detect locations where a conservation of energy principle is violated. We illustrate the approach with several numerical examples including skeletons of complex 2D and 3D shapes.
Migrating Sockets for networking with quality of service guarantees
Authors: D. K. Y. Yau, S. S. Lam
Venue: Proceedings of the 1997 International Conference on Network Protocols (ICNP '97) (1997)

Migrating Sockets is the protocol processing component of an end system architecture designed for networking with QoS guarantees. The architecture provides: (1) adaptive rate-controlled scheduling of protocol threads in Migrating Sockets, (2) rate-based flow control for reserved rate connections in future integrated services networks, and (3) a constant overhead active demultiplexing mechanism. Migrating Sockets achieves its efficiency by allowing user applications to manage a network endpoint with minimal system intervention, providing user level protocols read-only access to routing information in a "well-known" shared memory region, and integrating efficient kernel level support we previously built. It is backward compatible with Unix semantics and Berkeley sockets, and has been used to implement Internet protocols such as TCP, UDP and IP (including IP multicast). We also show that active demultiplexing supported by Migrating Sockets can be transparently enabled in wide-area TCP/IP internetworking (although it is not restricted to TCP/IP). We have an implementation of Migrating Sockets in Solaris 2.5. We discuss our implementation experience, and present performance results of our system running on the Ultra-1, SPARC 10 and SPARC 20 architectures.
TUKI: a data flow processor
Authors: Elaine French, Hugh Glaser
Venue: ACM SIGARCH Computer Architecture News (1983)

An important feature of the Japanese Fifth Generation initiative is the investigation of novel computer architectures. One promising field of interest is that of data flow architectures inspired by the work at MIT and Manchester University. Having recognised the connection between functional programming and data flow, the work at Westfield has concentrated on the design of high level applicative languages. In this paper we describe a data flow architecture that was designed to support our language CAJOLE. We discuss a single processor architecture, a prototype of which has been built, and that can now be used as the building block for a closely-coupled distributed system.
Research issues in the renovation of legacy systems
Authors: Arie Deursen, Paul Klint, Chris Verhoef
Venue:  (1999)

The goals of this tutorial are to: (\emph{i}) give the reader a quick introduction to the field of software renovation as a whole; (\emph{ii}) show that many techniques from compiler technology and formal methods can be applied; (\emph{iii}) demonstrate that research should be driven by real-life, industrial, case studies; and (\emph{iv}) indicate that many challenging problems are still unsolved. During the presentation of this turorial, demonstrations will be given of several of the case studies discussed here.
Facilitating Program Comprehension by Mining Association Rules from Source Code
Authors: Christos Tjortjis, Loukas Sinos, Paul Layzell
Venue: Proceedings of the 11th IEEE International Workshop on Program Comprehension (2003)

Program comprehension is an important part of software maintenance, especially when program structure is complex and documentation is unavailable or outdated. Data mining can produce structural views of source code thus facilitating legacy systems understanding.This paper presents a method for mining association rules from code aiming at capturing program structure and achieving better system understanding. A tool was implemented to assess this method. It inputs data extracted from code and derives association rules. Rules are then processed to abstract programs into groups containing interrelated entities. Entities are grouped together if their attributes participate in common rules. The abstraction is performed at the function level, in contrast to other approaches, that work at the program level.The method was evaluated using real, working programs. Programs are fed into a code analyser which produces the input needed for the mining tool. Results show that the method facilitates program comprehension by only using source code where domain knowledge andreliable documentation are not available or reliable.
Deterministic Optimal Routing for Two Heterogeneous Parallel Servers
Authors: K. Oida, K. Shinjo
Venue: Proceedings of the The 20th International Conference on Distributed Computing Systems ( ICDCS 2000) (2000)

This paper describes the characteristics of an optimal routing that assigns each arriving packet to one of two heterogeneous parallel servers. The characteristics are derived from numerical solutions to a routing problem, which finds an optimal routing that minimizes the average packet delay under the condition that the input traffic is completely deterministic.
On the Algebraic Structure of Quasi-cyclic Codes II: Chain Rings
Authors: San Ling, Patrick Solé
Venue: Designs, Codes and Cryptography (2003)

The ring decomposition technique of part I is extended to the case when the factors in the direct product decomposition are no longer fields but arbitrary chain rings. This includes not only the case of quasi-cyclic codes over rings but also the case of quasi-cyclic codes over fields whose co-index is no longer prime to the characteristic of the field. A new quaternary construction of the Leech lattice is derived.
AN AREA-EFFICIENT EUCLIDEAN ALGORITHM BLOCK FOR REED-SOLOMON DECODER
Authors: Hanho Lee
Venue: Proceedings of the IEEE Computer Society Annual Symposium on VLSI (ISVLSI'03) (2003)

This paper presents a new area-efficient architrecture to implement theEuclidean algorithm, which is frequently used in Reed-Solomon decoders.The RS (255,239) decoder using the Euclidean algorithm has been implemented with 0.13-µm CMOS technology with a supply voltage of 1.1V.We investigate hardware complexity, clock frequency and data processingrate for this Euclidean algorithm block. The results show that the totalnumber of gates is about 44,700 and it has a data processing rate of 2.4Gbits/s at a lock frequency of 300 MHz. As compared to the other RSdecoders, it gains significant improvements in hardware complexity andlatency.
Quadratic Programming is in NP
Authors: Stephen A. Vavasis
Venue:  (1990)

Quadratic programming is an important example of optimization with applications to engineering design, coombinatorical optimization, game theory, and economics. Garey and Johnson [1979] state that quadratic programming is NP-hard. In this report we show that it lies in NP, thereby proving that it is NP-complete.
Formal Callability and its Relevance and Application to Interprocedural Data-flow Analysis
Authors: Jens Knoop
Venue: Proceedings of the 1998 International Conference on Computer Languages (1998)

Formal callability is the problem of determining for every formal procedure call of a program the set of procedures it may call at run-time. This information is the key for constructing the procedure call graph of a program, a common prerequisite of static analyses of programs with procedures. Moreover, under specific side-conditions it reduces in interprocedural data-flow analysis the analysis of programs with formal procedure calls to the analysis of programs without formal calls by treating formal calls as higher-order branch statements. We demonstrate that formal callability yields as a by-product the solution of the well-known formal reachability problem. This directly implies that formal callability is in general not decidable. However, we show that formal callability is decidable for programs, where formal procedure parameters do not occur in procedures, which are local to the procedure of their declaration (usually known as programs without global (formal) procedure parameters), but within a time bound which is exponential in the program size. Thus, we complement the new decidability result by introducing in addition a safe approximation of formal callability called potential passability, which can efficiently be computed. Moreover, for programs of mode depth 2 (i.e., formal procedures do not have procedures as parameters) without global procedure parameters, formal callability and potential passability coincide.
A Logic for the Russell Programming Language
Authors: Hans Boehm
Venue:  (1984)

We consider a programming language with a number of characteristics detrimental to conventional axiomatic descriptions. These include arbitrary side effects in expressions, aliasing among variables, very general recursive function declarations, and the ability to pass functions as parameters and return them as results. We give an axiomatic definition of this language based on a novel formalism. We prove the axiomatization sound and relatively complete with respect to a (somewhat nonstandard) denotational semantics. In spite of the nonstandard formalism, most conventional techniques for developing and reasoning about programs can be carried over. (ABRIDGED)