ppxscal/embedding_network huggingface dataset:
Requirements for and evaluation of RMI protocols for scientific computing
Authors: Madhusudhan Govindaraju, Aleksander Slominski, Venkatesh Choppella, Randall Bramley, Dennis Gannon
Venue: Proceedings of the 2000 ACM/IEEE conference on Supercomputing (CDROM) (2000)

Distributed software component architectures provide a promising approach to the problem of building large scale, scientific Grid applications. Communication in these component architectures is based on Remote Method Invocation (RMI) protocols that allow one software component to invoke the functionality of another. Examples include Java remote method invocation (Java RMI) and the new Simple Object Access Protocol (SOAP). SOAP has the advantage that many programming languages and component frameworks can support it. This paper describes experiments showing that SOAP by itself is not efficient enough for large scale scientific applications. However, when it is embedded in a multi-protocol RMI framework, SOAP can be effectively used as a universal control protocol, that can be swapped out by faster, more special purpose protocols when large data transfer speeds are needed.
Notes on geometric weighted check digit verfication
Authors: J. G. Wilson
Venue: Communications of the ACM (1961)

This note describes a method for utilizing geometric weight modulus 11 checking digits on a computer which does not have either multiplication or division. In addition some attempt has been made to show some limitations of this system. 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
Dynamic Power Supply Current Testing of CMOS SRAMs
Authors: Jian Liu, Rafic Z. Makki, Ayman Kayssi
Venue: Journal of Electronic Testing: Theory and Applications (2000)

We describe the design and implementation of a dynamic power supply current sensor which is used to detect SRAM faults such as disturb faults as well as logic cell faults. A formal study is presented to assess the parameters that influence the sensor design. The sensor detects faults by detecting abnormal levels of the power supply current. The sensor is embedded in the SRAM and offers on-chip detectability of faults. The sensor detects abnormal dynamic current levels that result from circuit defects. If two or more memory cells erroneously switch as a result of a write or read operation, the level of the dynamic power supply current is elevated. The sensor can detect this elevated value of the dynamic current. The dynamic power supply current sensor can supplement the observability associated with any test algorithm by using the sensor as a substitute for the read operations. This significantly reduces the test length and the additional observability enhances defect coverages.
Using background knowledge to speed reinforcement learning in physical agents
Authors: Daniel Shapiro, Pat Langley, Ross Shachter
Venue: Proceedings of the fifth international conference on Autonomous agents (2001)

This paper describes Icarus, an agent architecture that embeds a hierarchical reinforcement learning algorithm within a language for specifying agent behavior. An Icarus program expresses an approximately correct theory about how to behave with options at varying levels of detail, while the Icarus agent determines the best options by learning from experience. We describe Icarus and its learning algorithm, then report on two experiments in a vehicle control domain. The first examines the benefit of new distinctions about state, whereas the second explores the impact of added plan structure. We show that background knowledge increases learning rate and asymptotic performance, and decreases plan size by three orders of magnitude, relative to the typical formulation of the learning problem in our test domain.
Modeling statecharts and activitycharts as signal equations
Authors: J.-R. Beauvais, E. Rutten, T. Gautier, R. Houdebine, P. Le. Guernic, Y.-M. Tang
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (2001)

The languages for modeling reactive systems are of different styles, like the imperative, state-based ones and the declarative, data-flow ones. They are adapted to different application domains. This paper, through the example of the languages Statecharts and Signal, shows a way to give a model of an imperative specification (Statecharts) in a declarative, equational one (Signal). This model constitutes a formal model of the Statemate semantics of Statecharts, upon which formal analysis techniques can be applied. Being a transformation from an imperative to a declarative structure, it involves the definition of generic models for the explicit management of state (in the case of control as well as of data). In order to obtain a structural construction of the model, a hierarchical and modular organization is proposed, including proper management and propagation of control along the hierarchy. The results presented here cover the essential features of Statecharts as well as of another language of Statemate: Activitycharts. As a translation, it makes multiformalism specification possible, and provides support for the integrated operation of the languages. The motivation lies also in the perspective of gaining access to the various formal analysis and implementation tools of the synchronous technology, using the DC1 exchange format, as in the Sacres programming environment.
Disk scheduling: FCFS vs.SSTF revisited
Authors: Micha Hofri
Venue: Communications of the ACM (1980)

We report on a rather extensive simulation effort directed at evaluating the merits of two scheduling strategies, FCFS and SSTF, for moving-arm disks under stationary request arrival process. For First-Come-First-Served (FCFS) scheduling, analytic results for the mean waiting time are also given (in a closed form). If the objective of a schedule is to minimize the mean waiting time (or queue size) and its variance, the results seem to confirm the overall superiority of Shortest-Seek-Time-First (SSTF), particularly for medium and heavy traffic. This holds also when the input is highly correlated or addresses the cylinders nonuniformly. These results contradict some statements published in recent years. The domain of policies where SSTF is optimal is considered. The simulation methodology is described in some detail.
An introduction to quantum computing for non-physicists
Venue: ACM Computing Surveys (CSUR) (2000)

Richard Feynman's observation that certain quantum mechanical effects cannot be simulated efficiently on a computer led to speculation that computation in general could be done more efficiently if it used these quantum effects. This speculation proved justified when Peter Shor described a polynomial time quantum algorithm for factoring intergers.In quantum systems, the computational space increases exponentially with the size of the system, which enables exponential parallelism. This parallelism could lead to exponentially faster quantum algorithms than possible classically. The catch is that accessing the results, which requires measurement, proves tricky and requires new nontraditional programming techniques.The aim of this paper is to guide computer scientists through the barriers that separate quantum computing from conventional computing. We introduce basic principles of quantum mechanics to explain where the power of quantum computers comes from and why it is difficult to harness. We describe quantum cryptography, teleportation, and dense coding. Various approaches to exploiting the power of quantum parallelism are explained. We conclude with a discussion of quantum error correction.
A selective traversal algorithm for binary search trees
Authors: James R. Driscoll, Y. Edmund Lien
Venue: Communications of the ACM (1978)

The problem of selecting data items from a binary search tree according to a list of range conditions is considered. The process of visiting a minimal number of nodes to retrieve data satisfying the range conditions is called selective traversal. Presented in this paper is an algorithm for selective traversal which uses a tag field for each node in the tree. The algorithm is particularly useful and efficient when examination of data is more time consuming than examination of a tag field.
Theory of dependence values
Authors: Rosa Meo
Venue: ACM Transactions on Database Systems (TODS) (2000)

A new model to evaluate dependencies in data mining problems is presented and discussed. The well-known concept of the association rule is replaced by the new definition of dependence value, which is a single real number uniquely associated with a given itemset. Knowledge of dependence values is sufficient to describe all the dependencies characterizing a given data mining problem. The dependence value of an itemset is the difference between the occurrence probability of the itemset and a corresponding &ldquo;maximum independence estimate.&rdquo; This can be determined as a function of joint probabilities of the subsets of the itemset being considered by maximizing a suitable entropy function. So it is possible to separate in an itemset of cardinaltiy k the dependence inherited from its subsets of cardinality (k &minus; 1) and the specific inherent dependence of that itemset. The absolute value of the difference between the probability p(i) of the event i that indicates the prescence of the itemset {a,b,... } and its maximum independence estimate is constant for any combination of values of Q &angl0; a,b,... &angr0; Q. In1p addition, the Boolean function specifying the combination of values for which the dependence is positive is a parity function. So the determination of such combinations is immediate. The model appears to be simple and powerful.
Exploring the Interaction between Java's Implicitly Thrown Exceptions and Instruction Scheduling
Authors: Matthew Arnold, Michael Hsiao, Ulrich Kremer, Barbara G. Ryder
Venue: International Journal of Parallel Programming (2001)

The frequent occurrence of implicitly thrown exceptions poses one of the challenges present in a Java compiler. Not only do these implicitly thrown exceptions directly affect the performance by requiring explicit checks, they also indirectly impact the performance by restricting code movement in order to satisfy the precise exception model in Java. In particular, instruction scheduling is one transformation that is restricted by implicitly thrown exceptions due to the heavy reliance on reordering instructions to exploit maximum hardware performance. The goal of this study is two-fold: first, investigate the degree to which implicitly thrown exceptions in Java hinder instruction scheduling, and second, find new techniques for allowing more efficient execution of Java programs containing implicitly thrown exceptions. Experimental results show that with aggressive scheduling techniques, such as superblock scheduling, the negative performance impact can be greatly reduced.
A model and stack implementation of multiple environments
Authors: Daniel G. Bobrow, Ben Wegbreit
Venue: Communications of the ACM (1973)

Many control and access environment structures require that storage for a procedure activation exist at times when control is not nested within the procedure activated. This is straightforward to implement by dynamic storage allocation with linked blocks for each activation, but rather expensive in both time and space. This paper presents an implementation technique using a single stack to hold procedure activation storage which allows retention of that storage for durations not necessarily tied to control flow. The technique has the property that, in the simple case, it runs identically to the usual automatic stack allocation and deallocation procedure. Applications of this technique to multitasking, coroutines, backtracking, label-valued variables, and functional arguments are discussed. In the initial model, a single real processor is assumed, and the implementation assumes multiple-processes coordinate by passing control explicitly to one another. A multiprocessor implementation requires only a few changes to the basic technique, as described.
A note on the set basis problem related to the compaction of character sets
Authors: Lawrence T. Kou, C. K. Wong
Venue: Communications of the ACM (1975)

This note discusses the reduction of the set basis problem to the clique cover problem.
Comparison of word-based and syllable-based retrieval for Tibetan (poster session)
Authors: Paul G. Hackett, Douglas W. Oard
Venue: Proceedings of the fifth international workshop on on Information retrieval with Asian languages (2000)

Tibetan retrieval based on automatically segmented words is compared with the use of overlapping syllable n-grams using a known-item retrieval evaluation. The optimal span of fixed-length n-grams is found to be 2 syllables, and indexing words is found to be as effective as indexing syllable bigrams.
Experimental evaluation of information retrieval through a teletypewriter
Authors: Morris Rubinoff, Samuel Bergman, Winifred Franks, Elayne R. Rubinoff
Venue: Communications of the ACM (1968)

Experiments designed to evaluate the capabilities of mechanized information retrieval systems, with emphasis on interactive (man-machine) language and on some of the mechanical and psychological limitations in their design, were conducted at the Moore School Information Systems Laboratory. The basic assumption of the research is that an information retrieval system that provides for man-machine dialogue at a remote inquiry terminal should provide a searcher with many of the tools which would be available to him were he actually performing his search at a library or repository of documents. Factors involved in evaluation of such a system include ease of use, learning time, and effectiveness of actual retrieval. Three experiments and the conclusions resulting from them are detailed.
Electronic peer review and peer grading in computer-science courses
Authors: Edward F. Gehringer
Venue: ACM SIGCSE Bulletin (2001)

We have implemented a peer-grading system for review of student assignments over the World-Wide Web and used it in approximately eight computer-science courses. Students prepare their assignments and submit them to our Peer Grader (PG) system. Other students are then assigned to review and grade the assignments. The system allows authors and reviewers to communicate with authors being able to update their submissions. Unique features of our approach include the ability to submit arbitrary sets of Web pages for review, and mechanisms for encouraging careful review of submissions. We have used the system to produce high-quality compilations of student work. Our assignment cycle consists of six phases, from signing up for an assignment to Web publishing of the final result. Based upon our experience with PG, we offer suggestions for improving the system to make it more easily usable by students at all levels.
An Augmented Conjugate Gradient Method for Solving Consecutive Symmetric Positive Definite Linear Systems
Authors: Jocelyne Erhel, Frédéric Guyomarc'h
Venue: SIAM Journal on Matrix Analysis and Applications (2000)

Many scientific applications require one to solve successively linear systems Ax=b with different right-hand sides $b$ and a symmetric positive definite matrix A. The conjugate gradient method applied to the first system generates a Krylov subspace which can be efficiently recycled thanks to orthogonal projections in subsequent systems. A modified conjugate gradient method is then applied with a specific initial guess and initial descent direction and a modified descent direction during the iterations. This paper gives new theoretical results for this method and proposes a new version. Numerical experiments show the efficacy of our method even for quite different right-hand sides.
A small OpenMath type system
Authors: James H. Davenport
Venue: ACM SIGSAM Bulletin (2000)

This paper describes the "light-weight" Small Type System of OpenMath. It is based on various discussion with the OpenMath Consortium, and notably with the NAG team. Section 7 lists the open issues for debate.
The changing face of software support: the impact of the Internet on customer support and support personnel
Authors: John M. Borton
Venue: Proceedings of the 2001 ACM SIGCPR conference on Computer personnel research (2001)

The site used to collect the data for this study (Beta Inc.) is a U.S.-based, international computing company with over 3000 support personnel employed world-wide. During the 12 month period from August 1999 to July 2000, the company moved the customer support operation from a telephone-based system to a mix of telephone and Internet-based support. The data presented in this paper was collected between January and July 2000 and shows the impact of this change on customer support and support personnel. Prior to the implementation of the Internet-based, iNet Customer Support System, the quantity of customer support, as a measure of operational performance for Beta Inc., was based on Telephone Support Request (SR) volume. Between January and July, 2000, there was a 52% decrease in telephone SRs across the company. This followed a three-year trend of increasing telephone SRs. This study shows that the decrease in telephone SRs has been made up through customer self-service using the iNet Customer Support System. As a result of this trend toward customer self-service using the Internet, 15% of the Beta Inc. customer support personnel were RIFed in June 2000. The change in the customer support service model at Beta Inc. impacts the required number of support personnel, the level of expertise required of customer support personnel, and the type of support which customers may expect in the future. Several conclusions are presented: The effort to move Beta Inc. customers to a self-service mode was very successful. Average resolution time of Internet-based SRs exceeded average resolution time of telephone SRs, suggesting that iNET provides customer solutions to simpler problems with the submission of more difficult support problems to support personnel. A measure of the quality of customer support self-service is needed. As more support questions are answered through customer searches of the iNET system, the number of support personnel required to answer support questions will continue to decrease. At the same time, since only the more difficult support questions are left unanswered by the iNET system the level of support personnel expertise required to answer customer questions will increase.
Experiences teaching software engineering for the first time
Authors: K. Todd Stevens
Venue: Proceedings of the 6th annual conference on Innovation and technology in computer science education (2001)

This paper presents an approach to teaching a Software Engineering course, as well as significant feedback from the students who were enrolled in the first offering of the course using this approach. The course provided students with conceptual material as well as experience with a large project. Just teaching concepts or major topics, while important, is not sufficient; students need hands-on exposure to doing a large project in order to comprehend the complexity of building real systems. On the other hand a course cannot "teach" only a project because students need a conceptual framework, approaches, and techniques upon which to base the complexities of software engineering. The feedback from the students who took the first offering of the course provides useful information to anyone who teaches Software Engineering, in addition to instructors preparing to teach the subject for the first time.
Scalable propagation-based call graph construction algorithms
Authors: Frank Tip, Jens Palsberg
Venue: Proceedings of the 15th ACM SIGPLAN conference on Object-oriented programming, systems, languages, and applications (2000)

Propagation-based call graph construction algorithms have been studied intensively in the 199Os, and differ primarily in the number of sets that are used to approximate run-time values of expressions. In practice, algorithms such as RTA that use a single set for the whole program scale well. The scalability of algorithms such as 0-CFA that use one set per expression remains doubtful.In this paper, we investigate the design space between RTA and 0-CFA. We have implemented various novel algorithms in the context of Jax, an application extractor for Java, and shown that they all scale to a 325,000-line program. A key property of these algorithms is that they do not analyze values on the run-time stack, which makes them efficient and easy to implement. Surprisingly, for detecting unreachable methods, the inexpensive RTA algorithm does almost as well as the seemingly more powerful algorithms. However, for determining call sites with a single target, one of our new algorithms obtains the current best tradeoff between speed and precision.
A redundancy check for ALGOL programs
Authors: Henry C. Thacher,  Jr.
Venue: Communications of the ACM (1962)

In using ALGOL, or any other common language for communicating among computers with different input-output media, one or more human beings is normally present in the communication channel. In the otherwise convenient method of communication by published algorithms, at least three humans are directly involved: a typist to prepare the manuscript in reference or publication language, a typesetter, and a keypunch operator to prepare the program for the computer in its hardware language. In spite of checking by authors, proof readers, editors, and verifiers, this process is a noisy one, involving as it does not only copying a synthetic (and therefore unfamiliar) language, but also translation to and from the publication dialect. The number of minor typographical errors which have been detected and reported in published algorithms confirms this observation. Clearly some check of the accuracy with which an algorithm has been transmitted through this noisy channel would be desirable. The solution which we propose is directed particularly to ALGOL 60, but the same problems exist with other common languages, and the principles which we use could be readily adapted to them.
Performance modeling for the panda array I/O library
Authors: Ying Chen, Marianne Winslett, Szu-wen Kuo, Yong Cho, Mahesh Subramaniam, Kent Seamons
Venue: Proceedings of the 1996 ACM/IEEE conference on Supercomputing (CDROM) (1996)

We present an analytical performance model for Panda, a library for synchronized i/o of large multidimensional arrays on parallel and sequential platforms, and show how the Panda developers use this model to evaluate Panda's parallel i/o performance and guide future Panda development. The model validation shows that system developers can simplify performance analysis, identify potential performance bottlenecks, and study the design trade-offs for Panda on massively parallel platforms more easily than by conducting empirical experiments. More importantly, we show that the outputs of the performance model can be used to help make optimal plans for handling application i/o requests, the first step toward our long-term goal of automatically optimizing i/o request handling in Panda.
Combining low-power scan testing and test data compression for system-on-a-chip
Authors: Anshuman Chandra, Krishnendu Chakrabarty
Venue: Proceedings of the 38th annual Design Automation Conference (2001)

We present a novel technique to reduce both test data voluem and scan power dissipation using test data compression for system-on-a-chip testing. Power dissipation during test mode using ATPG-compacted test patterns is much higher than during functional mode. We show that Golomb coding of precomputed test sets leads to significant savings in peak and average power, without requiring either a slower scan clock or blocking logic in the scan cells. We also improve upon prior work on Golomb coding by showing that a separate cyclical scan regiter is not necessary for pattern decompression. Experimental results for the larger ISCAS 89 benchmarks show that reduced test data volume and low power scan testing can indeed be achieved in all cases.