ppxscal/embedding_network huggingface dataset:
A highly parallel algorithm for approximating all zeros of a polynomial with only real zeros
Authors: Merrell L. Patrick
Venue: Communications of the ACM (1972)

An algorithm is described based on Newton's method which simultaneously approximates all zeros of a polynomial with only real zeros. The algorithm, which is conceptually suitable for parallel computation, determines its own starting values so that convergence to the zeros is guaranteed. Multiple zeros and their multiplicity are readily determined. At no point in the method is polynomial deflation used.
Searching in a dynamic memory with fast sequential access
Authors: Om Vikas, V. Rajaraman
Venue: Communications of the ACM (1982)

This communication presents an algorithm for searching in the Aho-Ullman dynamic memory consisting of (2m - 1) cells. Mean search time of 1.5m steps to the first specified record is obtained with a subsequent sequential access capability. Thus, in such a dynamic memory, the mean access time for content addressing is the same as the mean access time for random addressing.
Contention Resolution in Hashing Based Shared Memory Simulations
Authors: Artur Czumaj, Friedhelm Meyerauf der
Venue: SIAM Journal on Computing (2000)

In this paper we study the problem of simulating shared memory on the distributed memory machine (DMM). Our approach uses multiple copies of shared memory cells, distributed among the memory modules of the DMM via universal hashing. The main aim is to design strategies that resolve contention at the memory modules. Extending results and methods from random graphs and very fast randomized algorithms, we present new simulation techniques that enable us to improve the previously best results exponentially. In particular, we show that an $n$-processor CRCW PRAM can be simulated by an n-processor DMM with delay $\O(\log\log\log n \log^*n)$, with high probability.Next we describe a general technique that can be used to turn these simulations into time-processor optimal ones, in the case of EREW PRAMs to be simulated. We obtain a time-processor optimal simulation of an (n log log log n log*n)-processor EREW PRAM on an n-processor DMM with delay $\O(\log\log\log n \log^*n)$, with high probability. When an (n log log log n log*n)-processor CRCW PRAM is simulated, the delay is only by a log*n factor larger.We further demonstrate that the simulations presented can not be significantly improved using our techniques. We show an $\Omega(\log\log\log n / \log\log\log\log n)$ lower bound on the expected delay for a class of PRAM simulations, called topological simulations, that covers all previously known simulations as well as the simulations presented in the paper.
Composable collaboration infrastructures based on programming patterns
Authors: Vassil Roussev, Prasun Dewan, Vibhor Jain
Venue: Proceedings of the 2000 ACM conference on Computer supported cooperative work (2000)

In general, collaboration infrastructures have supported sharing of an object based on its logical structure. However, current implementations assume an implicit binding between this logical structure and particular system-defined abstractions. We present a new composable design based on programming patterns that eliminates this binding, thereby increasing the range of supported objects and supporting extensibility.
Numerical Analysis of Parabolic p-Laplacian: Approximation of Trajectories
Authors: Ning Ju
Venue: SIAM Journal on Numerical Analysis (2000)

The long time numerical approximation of the parabolic p-Laplacian problem with a time-independent forcing term and sufficiently smooth initial data is studied. Convergence and stability results which are uniform for $t\in [0,\infty)$ are established in the L2, W1,p norms for the backward Euler and the Crank--Nicholson schemes with the finite element method (FEM). This result extends the existing uniform convergence results for exponentially contractive semigroups generated by some semilinear systems to nonexponentially contractive semigroups generated by some quasi-linear systems.
A Projection-Regularized Newton Method for Nonlinear Ill-Posed Problems and Its Application to Parameter Identification Problems with Finite Element Discretization
Authors: Barbara Kaltenbacher
Venue: SIAM Journal on Numerical Analysis (2000)

This paper is concerned with nonlinear ill-posed operator equations F(a)=y (e.g., parameter identification problems) and their approximate solution by a Newton-type method that is regularized by projecting the linearized equation in each Newton step onto a finite-dimensional space (e.g., a finite element space) and by stopping the Newton iteration at an appropriate index. We prove convergence as the iteration index n goes to infinity in the noise-free case and convergence as the data noise level $\delta$ goes to zero in the case of noisy data, as well as convergence rates under certain additional conditions.
Enhancement of JPEG-Compressed Images by Re-application of JPEG
Authors: Aria Nosratinia
Venue: Journal of VLSI Signal Processing Systems (2001)

A novel method is proposed for post-processing of JPEG-encoded images, in order to reduce coding artifacts and enhance visual quality. Our method simply re-applies JPEG to the shifted versions of the already-compressed image, and forms an average. This approach, despite its simplicity, offers better performance than other known methods, including those based on nonlinear filtering, POCS, and redundant wavelets.
Component visualization based on programmer's conceptual models (poster session)
Authors: Ludger Martin, Elke Siemon
Venue: Addendum to the 2000 proceedings of the conference on Object-oriented programming, systems, languages, and applications (Addendum) (2000)

Current programming environments for user interface development provide visual programming techniques to aid in using object oriented and component technology concepts. We suggest a clear separation of visualizations for component assembly on the one hand and object oriented programming on the other hand, present metaphors and a programming environment.
Proof linking: modular verification of mobile programs in the presence of lazy, dynamic linking
Authors: Philip W. L. Fong, Robert D. Cameron
Venue: ACM Transactions on Software Engineering and Methodology (TOSEM) (2000)

Although mobile code systems typically employ link-time code verifiers to protect host computers from potentially malicious code, implementation flaws in the verifiers may still leave the host system vulnerable to attack. Compounding the inherent complexity of the verification algorithms themselves, the need to support lazy, dynamic linking in mobile code systems typically leads to architectures that exhibit strong interdependencies between the loader, the verifier, and the linker. To simplify verifier construction and provide improved assurances of verifier integrity, we propose a modular architecture based on the concept of proof linking. This architecture encapsulates the verification process and removes dependencies between the loader, the verifier, and the linker. We also formally model the process of proof linking and establish properties to which correct implementations must conform. As an example, we instantiate our architecture for the problem of Java bytecode verification and assess the correctness of this instantiation. Finally, we briefly discuss alternative mobile code verification architectures enabled by the proof-linking concept.
On accurate floating-point summation
Authors: Michael A. Malcolm
Venue: Communications of the ACM (1971)

cumulation of floating-point sums is considered on a computer which performs t-digit base &bgr; floating-point addition with exponents in the range &mdash;m to M. An algorithm is given for accurately summing n t-digit floating-point numbers. Each of these n numbers is split into q parts, forming q&middot;n t-digit floating-point numbers. Each of these is then added to the appropriate one of &eegr; auxiliary t-digit accumulators. Finally, the accumulators are added together to yield the computed sum. In all, q&middot;n + &eegr; - 1 t-digit floating-point additions are performed. Let &ngr; = &lceil;(M + m + 1)/(&eegr; + 1)&rceil;. If n &le; (1/q)&bgr;&lceil;((q-1)/q)t&lceil;-&ngr;+1 (*), then the relative error in the computed sum is at most &lceil;(t + 1)/&ngr;&rceil;&bgr;1-t. Further, with an additional q + &eegr; - 1 t-digit additions, the computed sum can be corrected to full t-digit accuracy. For example, for the IBM/360 (&bgr; = 16, t = 14, M = 63, m = 64), typical values for q and &eegr; are q = 2 and &eegr; = 32. In this case, (*) becomes n &le; 1/2 &times; 164 = 32,768, and we have &lceil;(t + 1)/&ngr;&rceil;&bgr;1-t = 4 &times; 16-13.
Multi-Input Floating Gate Differential Amplifier and Application to Intelligent Sensors
Authors: Takeyasu Sakai, Hiromasa Nagai, Takashi Matsumoto
Venue: Analog Integrated Circuits and Signal Processing (2000)

Multi-input floating gate differential amplifier (FGDA) is proposed which can perform any convolution operation with differential structure and feedback loop. All operations are in the voltage mode. Only one terminal is required for the negative feedback which can suppress distortions due to mismatches of active elements. Possible applications include intelligent image sensor, where fully parallel DCT operation can be performed. A prototype chip is fabricated which is functional. A preliminary test result is reported.
On a generalized language for file organization and manipulation
Authors: Charles W. Bachman
Venue: Communications of the ACM (1966)

I would like to speak on what I call a unified or generalized language for file organization and manipulation. I call it unified because some ideas from which disk file languages were developed are perfectly applicable to magnetic tape files, and would be a great improvement on the way we address files on magnetic tape today.
Synthesizing constraint expressions
Authors: Eugene C. Freuder
Venue: Communications of the ACM (1978)

A constraint network representation is presented for a combinatorial search problem: finding values for a set of variables subject to a set of constraints. A theory of consistency levels in such networks is formulated, which is related to problems of backtrack tree search efficiency. An algorithm is developed that can achieve any level of consistency desired, in order to preprocess the problem for subsequent backtrack search, or to function as an alternative to backtrack search by explicitly determining all solutions.
Temporal links: recording and replaying virtual environments
Authors: Chris Greenhalgh, Jim Purbrick, Steve Benford, Mike Craven, Adam Drozd, Ian Taylor
Venue: Proceedings of the eighth ACM international conference on Multimedia (2000)

Virtual reality (VR) currently lacks the kinds of sophisticated production technologies that are commonly available for established media such as video and audio. This paper introduces the idea of temporal links, which provide a flexible mechanism for replaying past or recent recordings of virtual environments within other real-time virtual environments. Their flexibility arises from a combination of temporal, spatial and presentational properties. Temporal properties determine the relationship between time in a live environment and time in a recording, including the apparent speed and direction of replay. Spatial properties determine the spatial relationship between the environment and the recording. Presentational properties determine the appearance of the recording within the environment. These properties may be fixed, dynamically varied by an application, or directly controlled in real-time by users. Consequently, temporal links have a wide variety of potential uses, including supporting post-production tools for virtual environments, post-exercise debriefing in training simulators, and asynchranous communication such as VR email, as well as providing new forms of content for virtual worlds that refer to past activity. We define temporal links and their properties and describe their implementation in the MASSIVE-3 Collaborative Virtual Environment (CVE) system, focusing on the underlying record and replay mechanisms. We also demonstrate applications for adding new content to an existing virtual world, and a VR post-production editor.
Parallel Matrix Multiplication on a Linear Array with a Reconfigurable Pipelined Bus System
Authors: Kequin Li, Victor Y. Pan
Venue: IEEE Transactions on Computers (2001)

The known fast sequential algorithms for multiplying two $N\times N$ matrices (over an arbitrary ring) have time complexity $O(N^\alpha)$, where $2
Exploitng event stream interpretation in publish-subscribe systems
Authors: Yuanyuan Zhao, Rob Strom
Venue: Proceedings of the twentieth annual ACM symposium on Principles of distributed computing (2001)

Publish-subscribe messaging middleware typically offers limited and low-level options for quality of service, such as best-effort delivery versus reliable delivery, or ordered versus unordered. We propose a new, high-level approach to specifying quality of service, in which the consumer specifies an event stream interpretation function that maps an event stream into a state that represents the consumer's semantics of the stream. Under this approach, the system may deliver either the subscribed event stream, or any alternative stream whose image under the interpretation function yields the same state. Event stream interpretation gives consumers the ability to more accurately specify the tolerable distortions of perfect message delivery, and gives middleware implementations the flexibility to use more efficient protocols for message delivery and failure recovery while preserving application safety. We introduce an event stream interpretation language. We illustrate its utility by applying it to the problem of optimistic delivery of unlogged and out-of-order messages. We show how a publish-subscribe system can take an event stream interpretation program supplied by a subscriber and, using techniques derived from compiler technology, analyze it to determine which messages can be delivered optimistically, and which recovery messages must be delivered when an unlogged or out-of-order message is detected.
An Opportunity Cost Approach for Job Assignment in a Scalable Computing Cluster
Authors: Yair Amir, Baruch Awerbuch, Amnon Barak, R. Sean Borgstrom, Arie Keren
Venue: IEEE Transactions on Parallel and Distributed Systems (2000)

A new method is presented for job assignment to and reassignment between machines in a computing cluster. Our method is based on a theoretical framework that has been experimentally tested and shown to be useful in practice. This ¿opportunity cost¿ method converts the usage of several heterogeneous resources in a machine to a single homogeneous ¿cost.¿ Assignment and reassignment are then performed based on that cost. This is in contrast to traditional, ad hoc methods for job assignment and reassignment. These treated each resource as an independent entity with its own constraints, as there was no clean way to balance one resource against another. Our method has been tested by simulations, as well as real executions, and was found to perform well.
On Estimating the Large Entries of a Convolution
Authors: Mikhail J. Atallah
Venue: IEEE Transactions on Computers (2001)

We give a Monte Carlo algorithm that computes an unbiased estimate of the convolution of two vectors. The variance of our estimate is small for entries of the convolution that are large; this corresponds to the situation in which convolution is used in pattern matching or template matching, where one is only interested in the largest entries of the resulting convolution vector. Experiments performed with our algorithm confirm the theory and suggest that, in contexts where one cares about only the large entries in the convolution, the algorithm can be a faster alternative to performing an FFT-based convolution.
Distance Education Using Linux and the MBone
Authors: Kelly Davis, Tom Miller, Charles Price
Venue: Linux Journal (2000)

There is more to the Internet than sending JPGs. See how Linux and the MBone addresses the nedds of distance learning.
Test Set and Fault Partitioning Techniques for Static Test Sequence Compaction for Sequential Circuits
Authors: Michael S. Hsiao, Srimat Chakradhar
Venue: Journal of Electronic Testing: Theory and Applications (2000)

We propose a new static test set compaction method based on a careful examination of attributes of fault coverage curves. Our method is based on two key ideas: (1) fault-list and test-set partitioning, and (2) vector re-ordering. Typically, the first few vectors of a test set detect a large number of faults. The remaining vectors usually constitute a large fraction of the test set, but these vectors are included to detect relatively few hard faults. We show that significant compaction can still be achieved by partitioning faults into hard and easy faults, and compaction is performed only for the hard faults. This significantly reduces the computational cost for static test set compaction without affecting quality of compaction. The second key idea re-orders vectors in a test set by moving sequences that detect hard faults to the beginning of the test set. Fault simulation of the newly concatenated re-ordered test set results in the omission of several vectors so that the compact test set is smaller than the original test set. Experiments on several ISCAS 89 sequential benchmark circuits and large production circuits show that our compaction procedure yields significant test set reductions in low execution times.
On the synthesis of decision tables
Authors: B. Srinivasan
Venue: Communications of the ACM (1983)

Synthesis of decision rules, each depicting a part of a decision process, is necessary in order to know the decision process in total perspective and to validate the consistency and the correctness of the decision logic. This paper proposes a method to synthesize a set of decision tables, each one of them representing a part of the decision logic, and thus serves as a tool for the system analyst in the system design phase.
Process locking: a protocol based on ordered shared locks for the execution of transactional processes
Authors: Heiko Schuldt
Venue: Proceedings of the twentieth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems (2001)

In this paper, we propose process locking, a dynamic scheduling protocol based on ideas of ordered shared locks, that allows for the correct concurrent and fault-tolerant execution of transactional processes. Transactional processes are well defined, complex structured collections of transactional services. The process structure comprises flow of control between single process steps and also considers alternatives for failure handling purposes. Moreover, the individual steps of a process may have different termination characteristics, i.e., they cannot be compensated once they have committed. All these constraints have to be taken into consideration when deciding how to interleave processes. However, due to the higher level semantics of processes, standard locking techniques based on shared and exclusive locks on data objects cannot be applied. Yet, process locking addresses both atomicity and isolation simultaneously at the appropriate level, the scheduling of processes, and accounts for the various constraints imposed by processes. In addition, process locking aims at providing a high degree of concurrency while, at the same time, minimizing execution costs. This is done by allowing cascading aborts for rather simple processes white this is prevented for complex, long-running processes within the same framework.
A C-based synthesis system, Bach, and its application (invited talk)
Authors: Takashi Kambe, Akihisa Yamada, Koichi Nishida, Kazuhisa Okada, Mitsuhisa Ohnishi, Andrew Kay, Paul Boca, Vince Zammit, Toshio Nomura
Venue: Proceedings of the 2001 Asia and South Pacific Design Automation Conference (2001)

In system LSI design, a desirable system is one that allows the designer to describe, partition, and verify systems, and to generate circuits efficiently. In this paper, we describe a C-based system LSI design system called Bach which we have developed. Using the example of an MEPG-4 video codec design, we summarize its design flow, effects and current issues.
Computer science education in a Saudi Arabian university: a comparative study of its B.Sc. program
Authors: Abdulmalik S. Al-Salman, Jacob Adeniyi
Venue: ACM SIGCSE Bulletin (2000)

The computer science curriculum at a university in the Kingdom of Saudi Arabia is described and then compared to with the CSAC/ABET accreditation criteria. The comparison is needed to determine the relevance of the curriculum in view of the dynamism and perturbations arising from the reality of the real world and CSAC/ABET criteria. The curriculum emphasizes breadth and depth in the main areas of computer science education and makes systems and systems development as its main subject area of expertise. The policy to adopt breadth and depth was based on the fact that Saudi Arabia is a young and rapidly developing country and computer science education in the country is at its infancy. The pre-college curriculum in the kingdom is lacking in computer science. In addition, computer science is a rapidly developing field. The graduates from this program were expected to be pioneering professionals in the emerging market of computer employment in the kingdom. The curriculum attempts to serve as a catalyst, providing a platform for discussion, which hopefully will result into a feedback to us. We also hope that the curriculum will serve as a guidance to third world countries which are in the same circumstances with limited capabilities and resources who may want to address the critical issues involved in computer science education.
The simulation of time sharing systems
Authors: Norman R. Nielsen
Venue: Communications of the ACM (1967)

The development of new large scale time-sharing systems has raised a number of problems for computation center management. Not only is it necessary to develop an appropriate hardware configuration for these systems, but appropriate software adjustments must be made. Unfortunately, these systems often do not respond to changes in the manner that intuition would suggest, and there are few guides to assist in the analysis of performance characteristics. The development of a comprehensive simulation model to assist in the investigation of these questions is described in this paper. The resulting model has a general purpose design and can be used to study a variety of time-sharing systems. It can also be used to assist in the design and development of new time-sharing algorithms or techniques. For the sake of efficiency and greater applicability, the model was implemented in a limited FORTRAN subset that is compatible with most FORTRAN IV compilers. The use of the simulation is demonstrated by a study of the IBM 360/67 time-sharing system.
Using visualization to teach novices recursion
Authors: Wanda Dann, Stephen Cooper, Randy Pausch
Venue: ACM SIGCSE Bulletin (2001)

This paper describes an approach for introducing recursion, as part of a course for novice programmers. The course is designed to make use of a 3-D animation world-builder as a visualization tool that allows students to see their own programs in action. One of the pedagogical goals of the course is to enable the student to gain an intuitive sense of and mathematical insight into the recursive process. The software, examples of animation using recursion, and some experiences in using this approach are discussed.