ppxscal/embedding_network huggingface dataset:
Diamond Quorum Consensus for High Capacity and Efficiency in a Replicated Database System
Authors: Ada Wai-Chee Fu, Yat Sheung Wong, Man Hon Wong
Venue: Distributed and Parallel Databases (2000)

Many quorum consensus protocols have been proposed for the management of replicated data in a distributed environment. The advantages of a replicated database system over a non-replicated one include high availability and low response time. We note further that the multiple sites can act as multiple agents so that at any time, multiple requests can be handled in parallel. This feature leads to the desirable consequence of high workload capacity. In this paper, we define a new metric of read-capacity for this feature. We propose a new protocol called diamond quorum consensus which has two major properties that are superior to the previous protocols of majority, tree, grid, and hierarchical quorum consensus: (1) it has the highest read-capacity, (2) it has the smallest optimal read quorum size of 2. We show that these two features are achievable without jeopardizing the availability. The small quorum size is a significant feature because it relates to the messaging cost. Few previous work on quorum consensus has discussed the handling of partition failure, which in many cases will depend on the quorum consensus protocol, we show how we can use the generalized virtual partition protocol to handle partition failure in the case of diamond quorum consensus.
Updating a database in an unsafe environment
Authors: Anthony I. Hinxman
Venue: Communications of the ACM (1984)

Normally, when an application makes use of a database, considerable resources are invested in maintaining the integrity of that database. However, in situations where use of a database may be desirable even though the normal level of resources is unavailable, a simple technique using a partitioned data file protects the database if immediate transaction recording is not essential.
A Validation of the Component-Based Method for Software Size Estimation
Authors: José Javier Dolado
Venue: IEEE Transactions on Software Engineering (2000)

Estimation of software size is a crucial activity among the tasks of software management. Work planning and subsequent estimations of the effort required are made based on the estimate of the size of the software product. Software size can be measured in several ways: Lines of code (LOC) is a common measure and is usually one of the independent variables in equations for estimating effort. There are several methods for estimating the final LOC count of a software system in the early stages. In this article, we report the results of the validation of the component-based method (initially proposed by Verner and Tate) for software sizing. This was done through the analysis of 46 projects involving more than 100,000 LOC of a fourth-generation language. We present several conclusions concerning the predictive capabilities of the method. We observed that the component-based method behaves reasonably, although not as well as expected for ¿global¿ methods such as Mark II function points for software size prediction. The main factor observed that affects the performance is the type of component.
Searcher performance in question answering
Authors: Mingfang Wu, Michael Fuller, Ross Wilkinson
Venue: Proceedings of the 24th annual international ACM SIGIR conference on Research and development in information retrieval (2001)

There are many tasks that require information finding. Some can be largely automated, and others greatly benefit from successful interaction between system and searcher. We are interested in the task of answering questions where some synthesis of information is required-the answer would not generally be given from a single passage of a single document. We investigate whether variation in the way a list of documents is delivered affected searcher performance in the question answering task. We will show that there is a significant difference in performance using a list customized to the task type, compared with a standard web-engine list. This indicates that paying attention to the task and the searcher interaction may provide substantial improvement in task performance.
Using handheld computers in the classroom: laboratories and collaboration on handheld machines
Authors: Michael J. Jipping, Joshua Krikke, Sarah Dieter, Samantha Sandro
Venue: ACM SIGCSE Bulletin (2001)

Handheld computers provide a unique opportunity for teaching computer science. They are inexpensive (and keep dropping in price); they are powerful; they are accessible by students; and they run standard programming interfaces. These facets combine to provide a unique platform for teaching. This paper documents a project to integrate handheld machines into the classroom. We develop the case for using these machines; we overview our plans to use them; and we showcase two applications that we are using in classes. These applications are available for download from the Internet and represent a beginning for our project.
Some basic terminology connected with mechanical languages and their processors: a tentative base terminology presented to ASA x3.4 as a proposal for subsequent inclusion in a glossary
Authors: Saul Gorn
Venue: Communications of the ACM (1961)

The suggestions in this paper are part of the terminology used in work for the University of Pennsylvania's Office of Computer Research and Education. The work is jointly supported by the National Science Foundation* and the Air Force Office of Scientific Research.&dagger;
Programming pearls: graphic output
Authors: Jon L. Bentley
Venue: Communications of the ACM (1984)

In previous columns we've studied the innards of programs. In this column we'll take a broader view of the programmer's task and consider the kind of output a program should produce. We'll focus on a single problem: once a system has produced detailed output, how can it summarize the trends in the mountain of data? The answer to that question depends heavily on both the data and the taste of the reader; paragraphs of text and tables of numbers often provide fine summaries. This column, however, will concetrate on graphical representations of data, which allow the powerful human vision system to understand data. A decade ago programmers could offer the excuse that they were limited to crude line printer graphics, but technology has changed that. Many large installations now have laser printers, and graphics printers for home computers sell for a few hundred dollars. This column is about ways that programmers can use the technology to deliver more useful (and more graphic) output.
Source-level execution time estimation of C programs
Authors: C. Brandolese, W. Fornaciari, F. Salice, D. Sciuto
Venue: Proceedings of the ninth international symposium on Hardware/software codesign (2001)

In this paper a comprehensive methodology for software execution time estimation is presented. The methodology is supported by rigorous mathematical models of C statements in terms of elementary operations. The deterministic contribution is combined with a statistical term accounting for all those aspects that cannot be quantified exactly. The methodology has been validated by realizing a complete prototype toolset, used to carry out the experiments.
The Berkeley UNIX Consultant Project
Authors: Robert Wilensky, David N. Chin, Marc Luria, James Martin, James Mayfield, Dekai Wu
Venue: Artificial Intelligence Review (2000)

UC (UNIX Consultant) is an intelligent, natural-language interface that allows naive users to learn about the UNIX operating system. UC was undertaken because the task was thought to be both a fertile domain for Artificial Intelligence research and a useful application of AI work in planning, reasoning, natural language processing, and knowledge representation. The current implementation of UC comprises the following components: A language analyzer, called ALANA, that produces a representation of the content contained in an utterance&semi; an inference component called a concretion mechanism that further refines this content&semi; a goal analyzer, PAGAN, that hypothesizes the plans and goals under which the user is operating; an agent, called UCEgo, that decides on UC's goals and proposes plans for them&semi; a domain planner, called KIP, that computes a plan to address the user's request&semi; an expression mechanism, UCExpress, that determines the content to be communicated to the user, and a language production mechanism, UCGen, that expresses UC's response in English. UC also contains a component called KNOME that builds a model of the user's knowledge state with respect to UNIX. Another mechanism, UCTeacher, allows a user to add knowledge of both English vocabulary and facts about UNIX to UC's knowledge base. This is done by interacting with the user in natural language. All these aspects of UC make use of knowledge represented in a knowledge representation system called KODIAK. KODIAK is a relation-oriented system that is intended to have wide representational range and a clear semantics, while maintaining a cognitive appeal. All of UC's knowledge, ranging from its most general concepts to the content of a particular utterance, is represented in KODIAK.
Interpreting Stale Load Information
Authors: Michael Dahlin
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

In this paper, we examine the problem of balancing load in a large-scale distributed system when information about server loads may be stale. It is well-known that sending each request to the machine with the apparent lowest load can behave badly in such systems, yet this technique is common in practice. Other systems use round-robin or random selection algorithms that entirely ignore load information or that only use a small subset of the load information. Rather than risk extremely bad performance on one hand or ignore the chance to use load information to improve performance on the other, we develop strategies that interpret load information based on its age. Through simulation, we examine several simple algorithms that use such load interpretation strategies under a range of workloads. Our experiments suggest that by properly interpreting load information, systems can: 1) match the performance of the most aggressive algorithms when load information is fresh relative to the job arrival rate, 2) outperform the best of the other algorithms we examine by as much as 60 percent when information is moderately old, 3) significantly outperform random load distribution when information is older still, and 4) avoid pathological behavior even when information is extremely old.
Verification of Array, Record, and Pointer Operations in Pascal
Authors: David C. Luckham, Norihisa Suzuki
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1979)

A practical method is presented for automating in a uniform way the verification of Pascal programs that operate on the standard Pascal data structures Array, Record, and Pointer. New assertion language primitives are introduced for describing computational effects of operations on these data structures. Axioms defining the semantics of the new primitives are given. Proof rules for standard Pascal operations on data structures are then defined using the extended assertion language. An axiomatic rule for the Pascal storage allocation operation, NEW, is also given. These rulers have been implemented in the Stanford Pascal program verifier. Examples illustrating the verification of programs which operate on list structures implemented with pointers and records are discussed. These include programs with side effects.
Glypnir&mdash;a programming language for Illiac IV
Authors: D. H. Lawrie, T. Layman, D. Baer, J. M. Randal
Venue: Communications of the ACM (1975)

GLYPNIR is one of the earliest existing languages designed for programming the Illiac IV computer. The syntax of the language is based on ALGOL 60, but has been extended to allow the programmer explicitly to specify the parallelism of his algorithm in terms of 64-word vectors. This paper describes the characteristics, goals, and philosophy of the language, and discusses some of the problems associated with parallel computer architectures.
Toward an understanding of data structures
Authors: Jay Earley
Venue: Communications of the ACM (1971)

This paper presents a notation and formalism for describing the semantics of data structures. This is based on directed graphs with named edges and transformations on these graphs. In addition, and implementation facility is described which could be part of a programming language, which allows a programmer who has expressed the semantics of an algorithm in terms of the graphs to then specify the implementation of some of his data structures in order to gain efficiency.
Packed scatter tables
Authors: Gordon Lyon
Venue: Communications of the ACM (1978)

Scatter tables for open addressing benefit from recursive entry displacements, cutoffs for unsuccessful searches, and auxiliary cost functions. Compared with conventional methods, the new techniques provide substantially improved tables that resemble exact-solution optimal packings. The displacements are depth-limited approximations to an enumerative (exhaustive) optimization, although packing costs remain linear&mdash;O(n)&mdash;with table size n. The techniques are primarily suited for important fixed (but possibly quite large) tables for which reference frequencies may be known: op-code tables, spelling dictionaries, access arrays. Introduction of frequency weights further improves retrievals, but the enhancement may degrade cutoffs.
Algorithms for identifying protein cross-links via tandem mass spectrometry
Authors: Ting Chen, Jacob D. Jaffe, George M. Church
Venue: Proceedings of the fifth annual international conference on Computational biology (2001)

Cross-linking technology combined with tandem mass spectrometry (MS-MS) is a powerful method that provides a rapid solution to the discovery of protein-protein interactions and protein structures. We studied the problem of detecting cross-linked peptides and cross-linked amino acids from tandem mass spectral data. Our method consists of two steps: the first step finds two protein subsequences whose mass sum equals a given mass measured from the mass spectrometry; and the second step finds the best cross-linked amino acids in these two peptide sequences that are optimally correlated to a given tandem mass spectrum. We designed fast and space-efficient algorithms for these two steps, and implemented and tested them on experimental data of cross-linked Hemoglobin proteins.
Power and Speed-Efficient Code Transformation of Video Compression Algorithms for RISC Processors
Authors: Lode Nachtergaele, Toon Gijbels, Jan Bormans, Francky Catthoor, Ivo Bolsens
Venue: Journal of VLSI Signal Processing Systems (2001)

Upcoming multi-media compression applications will require high memory bandwidth. In this paper, we estimate that a software reference implementation of an MPEG-4 video decoder typically requires 200 Mtransfers/s to memory to decode 1 CIF (352&times;288) Video Object Plane (VOP) at 30 frames/s. This imposes a high penalty in terms of power but also performance.However, we also show that we can heavily improve on the memory transfers, without sacrificing speed (even gaining about 10% on cache misses and cycles for a DEC Alpha), by aggressive code transformations. For this purpose, we have manually applied an extended version of our data transfer and storage exploration (DTSE) methodology, which was originally developed for custom hardware implementations.
On Dual Convergence of the Generalized Proximal Point Method with Bregman Distances
Authors: Alfredo Iusem, Renato D.C. Monteiro
Venue: Mathematics of Operations Research (2000)

The use of generalized distances (e.g., Bregman distances), instead of the Euclidean one, in the proximal point method for convex optimization, allows for elimination of the inequality constraints from the subproblems. In this paper we consider the proximal point method with Bregman distances applied to linearly constrained convex optimization problems, and study the behavior of the dual sequence obtained from the optimal multipliers of the linear constraints of each subproblem. Under rather general assumptions, which cover most Bregman distances of interest, we obtain an ergodic convergence result, namely that a sequence of weighted averages of the dual sequence converges to a specific point of the dual optimal set. As an intermediate result, we prove under the same assumptions that the dual central path generated by a large class of barriers, including the generalized Bregman distances, converges to the same point.
The interface between computer science and the mathematical sciences
Authors: Dianne P. O'Leary, Scott T. Weidman
Venue: Computing in Science and Engineering (2001)

On 28-29 April 2000, the Board on Mathematical Sciences and the Computer Science and Telecommunications Board of the National Research Council cosponsored a workshop on the interface between the mathematical sciences and three areas of computer science: network traffic modeling, computer vision, and data mining. The workshop's goal was to identify some open research questions in the mathematical sciences whose solutions could contribute to important unsolved problems in those computer science disciplines. The 48 participants engaged in lively discussions and identified at least 36 research challenges of a mathematical, statistical, or probabilistic nature.
JKarelRobot: a case study in supporting levels of cognitive development in the computer science curriculum
Authors: Duane Buck, David J. Stucki
Venue: ACM SIGCSE Bulletin (2001)

We introduce a new software tool, JKarelRobot, for supporting an Inside/Out pedagogy in introductory programming courses. Extending the original conception of "Karel the Robot", with Bloom's Taxonomy of Educational Objectives as a guiding principle, we have provided a mechanism for designing exercises that are cognitively appropriate to the developmental levels of our students. JKarelRobot is platform independent (written in Java) and language/paradigm independent, supporting Pascal, Java, and Lisp style environments.
Discrete comprehensive Gr&ouml;bner bases
Authors: Yosuke Sato, Akira Suzuki
Venue: Proceedings of the 2001 international symposium on Symbolic and algebraic computation (2001)

We show special types of comprehensive Gr&ouml;bner bases can be defined and calculated as the applications of Gr&ouml;bner bases in polynomial rings over Von Neumann regular rings.
Classroom collaboration in the design of tangible interfaces for storytelling
Authors: Danae Stanton, Victor Bayon, Helen Neale, Ahmed Ghali, Steve Benford, Sue Cobb, Rob Ingram, Claire O'Malley, John Wilson, Tony Pridmore
Venue: Proceedings of the SIGCHI conference on Human factors in computing systems (2001)

We describe the design of tangible interfaces to the KidPad collaborative drawing tool. Our aims are to support the re-enactment of stories to audiences, and integration within real classroom environments. A six-month iterative design process, working with children and teachers in school, has produced the &ldquo;magic carpet&rdquo;, an interface that uses pressure mats and video-tracked and barcoded physical props to navigate a story in KidPad. Reflecting on this process, we propose four guidelines for the design of tangible interfaces for the classroom. (1) Use physical size and shysical props to encourage collaboration. (2) Be aware of how different interfaces emphasize different actions. (3) Be aware that superficial changes to the design can produce very different physical interactions. (4) Focus on open low-tech technologies rather than (over) polished products.
Dealing with software process deviations using fuzzy logic based monitoring
Authors: Sorana Cîmpan, Flavio Oquendo
Venue: ACM SIGAPP Applied Computing Review (2000)

The work presented in this paper concerns the monitoring of software processes using a fuzzy logic based approach. The proposed monitoring for software processes focuses on the detection of deviations with respect to given models. The level of deviation is computed for different aspects of the process like progress, cost, structure (order between activities), etc. The proposed approach is implemented by the OMEGA environment (OMEGA stands for On-line Monitoring Environment: General and Adaptable). The environment provides a language for defining monitoring models. Such models are executed by the environment's engine. Fuzzy sets theory is used in the representation of the Information handled by monitoring systems, and possibility theory in the reasoning upon it. Fuzzy logic offers significant advantages over other approaches due to its ability to naturally represent uncertain and imprecise information. It equally provides a good framework for approximate reasoning. The use of the proposed monitoring environment is illustrated in the context of the Unified Software Development Process.
The convex hull of ellipsoids
Authors: Nicola Geismann, Michael Hemmer, Elmar Schömer
Venue: Proceedings of the seventeenth annual symposium on Computational geometry (2001)

The treatment of curved algebraic surfaces becomes more and more the f ocus of attention in Computational Geometry. We present a video that illustrates the computation of the convex hull of a set of ellipsoids. The underlying algorithm is an application of our work on determining a cell in a 3-dimensional arrangement of quadrics, see \cite{ghs-ccaq-01}. In the video, the main emphasis is on a simple and comprehensible visualization of the geometric aspects of the algorithm. In addition, we give some insights into the underlying mathematical problems.
Extensionality and intensionality of the ambient logics
Authors: Davide Sangiorgi
Venue: ACM SIGPLAN Notices (2001)

The ambient logic has been proposed for expressing properties of process mobility in the calculus of Mobile Ambients (MA), and as a basis for query languages on semistructured data. To understand the extensionality and the intensionality of the logic, the equivalence on MA processes induced by the logic (=L) iscompared with the standard MA behavioural equivalence and with structural congruence (an intensional equivalence, used as an auxiliary relation in thedefinition of satisfaction of the logic). The main contributions include a co-inductive characterisation of L as a form of labelled bisimilarity, and axiomatisations of L on the synchronous and asynchronous (finite) calculus. The study shows that, surprisingly, the logic allows us to observe the internal structure of the processes at a very finegrained detail, much in the same way as structural congruence does. A spin-off of the study is a better understanding of behavioural equivalence in Ambient-like calculi. For instance, behavioural equivalence is shown to be insensitive to stuttering phenomena originated by processes that may repeatedly enter and exit an ambient.
Enterprise traffic with a differentiated service mechanism
Authors: Chyan Yang
Venue: International Journal of Network Management (2001)

As an enterprise grows, its network bandwidth requirement also increases dramatically. Network performance of an enterprise will impact its operational performance. How do we efficiently manage an enterprise network&apos;s resources in an E&hyphen;business era&quest; This research proposes a differentiated service mechanism to manage traffic flows in an enterprise. This mechanism would enhance the performance of an enterprise network and help an enterprise efficiently transmits important information. With a high&hyphen;performance enterprise network, the enterprise can then operate more efficiently and improves its competitive capability. Copyright &copy; 2001 John Wiley Sons, Ltd.