ppxscal/embedding_network huggingface dataset:
Slipstream processors: improving both performance and fault tolerance
Authors: Karthik Sundaramoorthy, Zach Purser, Eric Rotenberg
Venue: ACM SIGPLAN Notices (2000)

Processors execute the full dynamic instruction stream to arrive at the final output of a program, yet there exist shorter instruction streams that produce the same overall effect. We propose creating a shorter but otherwise equivalent version of the original program by removing ineffectual computation and computation related to highly-predictable control flow. The shortened program is run concurrently with the full program on a chip multiprocessor or simultaneous multithreaded processor, with two key advantages:1) Improved single-program performance. The shorter program speculatively runs ahead of the full program and supplies the full program with control and data flow outcomes. The full program executes efficiently due to the communicated outcomes, at the same time validating the speculative, shorter program. The two programs combined run faster than the original program alone. Detailed simulations of an example implementation show an average improvement of 7% for the SPEC95 integer benchmarks.2) Fault tolerance. The shorter program is a subset of the full program and this partial-redundancy is transparently leveraged for detecting and recovering from transient hardware faults.
The computer science research network CSNET: a history and status report
Authors: Douglas Comer
Venue: Communications of the ACM (1983)

In 1981, the National Science Foundation started a five-year project totaling nearly $5 million to construct a computer science research network, CSNET, connecting all groups engaged in computer science research. For an NSF division with an annual budget of $25 million, the award represents an unusual commitment to a single project; only a handful of such large awards have been made. What is CSNET? Why is it receiving such attention? How will it benefit the community? When will it be completed? Who are the architects and implementors?
Replicated condition monitoring
Authors: Yongqiang Huang, Hector Garcia-Molina
Venue: Proceedings of the twentieth annual ACM symposium on Principles of distributed computing (2001)

A condition monitoring system tracks real-world variables and alerts users when a predefined condition becomes true, e.g., when stock price drops, or when a nuclear reactor over-heats. Replication of monitoring servers can reduce the probability that an important alert is missed. However, replicated independent servers can sometimes report &ldquo;conflicting&rdquo; alerts to the user, causing confusion. In this paper, we study the problem of replicated condition monitoring. We identify and formally define three desirable properties of a replicated system, namely, orderedness, consistency, and completeness. We propose new monitoring algorithms that enforce some or all of the desired properties in different scenarios.
A program for the syntactic analysis of English sentences
Authors: Hamish Dewar, Paul Bratley, James Peter Thorne
Venue: Communications of the ACM (1969)

A program is described which produces syntactic analyses of English sentences with respect to a transformational grammar. The main features of the analyzer are that it uses only a limited dictionary of English words and that it pursues all analysis paths simultaneously while processing the sentence from left to right. The form of representation used for the dictionary and the grammar is indicated and an outline account is given of the analysis procedure. Techniques for keeping the size of the analysis record within reasonable limits and for avoiding the need for dynamic application of certain transformational rules are described. A number of examples of output produced by the program are given. The output includes timing information.
Multiple ways to incorporate Oracle's database and tools into the entire curriculum
Authors: Catherine C. Bareiss
Venue: Journal of Computing Sciences in Colleges (2001)

It is not uncommon for students to view the curriculum as pieces instead of an integrated whole. This can hinder them from applying knowledge learned previously in one course to the course they are currently taking. In addition there are a number of recurring concepts in computer science that students need to recognize. The concepts associated with the management of large amounts of information is one such area.
Deriving hard real-time embedded systems implementations directly from SDL specifications
Authors: J. M. Alvarez, M. Diaz, L. Llopis, E. Pimentel, J. M. Troyal
Venue: Proceedings of the ninth international symposium on Hardware/software codesign (2001)

Object-Oriented methodologies together with Formal Description Techniques (FDT) are a promising way to deal with the increasing complexity of hard real-time embedded systems. However, FDTs do not take into account non-functional aspects as real-time constraints. Based on a new real-time execution model for FDT SDL proposed in previous works, a way to derive implementations of hard real-time embedded systems directly from SDL specifications is presented. In order to get it we propose a middleware that supports this model to organize the execution of the tasks generated from SDL system specification. Additionally, a worst case real-time analysis, including the middleware overhead, is presented. Finally, an example to generate the implementation from the SDL specification and a performance study is developed.
On the normalization requirement of divisor in divide-and-correct methods
Authors: E. V. Krishnamurthy, Salil K. Nandi
Venue: Communications of the ACM (1967)

This paper presents an analysis on the normalization requirement of the divisor in a divide-and-correct method. This analysis is made subject to the condition that not more than one correction is required to obtain the true quotient character, from the trial estimate got from the division of a two-precision segment of every partial remainder by a suitably rounded single-precision divisor. (This segmented division is denoted here as a (2, 1) precision basic division.) It is found that the normalization requirement could be narrowed down to a smaller range of divisors, provided the magnitude of the character next to the leading character of the divisor is known. If, however, the normalization is to be eliminated one has to choose proper higher precision segments of operands for the basic division. Also considered is the possibility of eliminating the normalization by an increase on the number of corrections on the quotient estimate got from a (2, 1) precision basic division. It is shown that such a scheme is economical only for small radices.
Covering edges by cliques with regard to keyword conflicts and intersection graphs
Authors: L. T. Kou, L. J. Stockmeyer, C. K. Wong
Venue: Communications of the ACM (1978)

Kellerman has presented a method for determining keyword conflicts and described a heuristic algorithm which solves a certain combinatorial optimization problem in connection with this method. This optimization problem is here shown to be equivalent to the problem of covering the edges of a graph by complete subgraphs with the objective of minimizing the number of complete subgraphs. A relationship between this edge-clique-cover problem and the graph coloring problem is established which allows algorithms for either one of these problems to be constructed from algorithms for the other. As consequences of this relationship, the keyword conflict problem and the edge-clique-cover problem are shown to be NP-complete, and if P &ne; NP then they do not admit polynomial-time approximation algorithms which always produce solutions within a factor less than 2 from the optimum.
A method for composing simple traditional music by computer
Authors: Gary M. Rader
Venue: Communications of the ACM (1974)

A method is described for composing musical rounds by computer. This method uses some music theory plus additional heuristics. Fundamental to the method is a set of productions together with sets of applicability rules and weight rules which operate on the productions deciding when and to what extent they are available for use. Several rounds generated by the computer implementation of the method are presented. Generally, the resultant music sounds mediocre to the professional although usually pleasing to the layman. It appears that full-blown music theory is not needed for rounds&mdash;all the hardware required for structural levels is not necessary for these pieces. The author has tried to address both musicians and computer scientists.
Expressive retrieval from XML documents
Authors: Taurai Tapiwa Chinenyanga, Nicholas Kushmerick
Venue: Proceedings of the 24th annual international ACM SIGIR conference on Research and development in information retrieval (2001)

The emergence of XML as a standard interchange format for structured documents/data has given rise to many XML query language proposals. However, some of these languages do not support information retrieval-style ranked queries based on textual similarity. There have been several extensions to these query languages to support keyword search, but the resulting query languages cannot express queries such as``find books and CDs with similar titles''. Either these extensions use keywords as mere boolean filters, or similarities can be calculated only between data values and constants rather than two data values. We propose ELIXIR, an \textbf{\underline{e}}xpressive and \textbf{\underline{e}}fficient\textbf{\underline{l}}anguage for \textbf{\underline{X}}ML \textbf{\underline{i}}nformation \textbf{\underline{r}}etrieval that extends the query language XML-QL \cite{deutsch-www8,deutsch-deb99} with a textual similarity operator. ELIXIR is a general-purpose XML information retrieval language, sufficiently expressive to handle the above query. Our algorithm for answering ELIXIR queries rewrites the original ELIXIR query into a series of XML-QL queries that generate intermediate relational data, and uses relational database techniques to efficiently evaluate the similarity operators on this intermediate data, yielding an XML document with nodes ranked by similarity. Our experiments demonstrate that our prototype scales well with the size of the XML data and complexity of the query.
Synchronous distance learning via the Internet experience and status report &ndash;
Authors: John Sigle
Venue: Journal of Computing Sciences in Colleges (2001)

Remote conferencing via the Internet will soon provide a cost effective and convenient avenue for distance learning. Used in conjunction with the asynchronous methods that are currently popular, both virtual classrooms and virtual office visits will provide ready access to instruction from a student's home or office. While some short-term technical impediments exist, the real bottlenecks are more likely to be in the areas of preparing institutions and instructors to use the technology and to use it effectively. This paper describes some of the technology involved, some of the current impediments, technical and otherwise. It also shares some experience and lessons learned in the use of this technology through a project funded by NSF and Louisiana Board of Regents grants.
A mathematical programming updating method using modified Givens transformations and applied to LP problems
Authors: Richard J. Hanson, John A. Wisniewski
Venue: Communications of the ACM (1979)

An efficient and numerically stable method is presented for the problem of updating an orthogonal decomposition of a matrix of column (or row) vectors. The fundamental idea is to add a column (or row) analogous to adding an additional row of data in a linear least squares problem. A column (or row) is dropped by a formal scaling with the imaginary unit, &radic;-1, followed by least squares addition of the column (or row). The elimination process for the procedure is successive application of the Givens transformation in modified (more efficient) form. These ideas are illustrated with an implementation of the revised simplex method. The algorithm is a general purpose one that does not account for any particular structure or sparsity in the equations. Some suggested computational tests for determining signs of various controlling parameters in the revised simplex algorithm are mentioned. A simple means of constructing test cases and some sample computing times are presented.
Dynamically Relaxed Block Incomplete Factorizations for Solving Two- and Three-Dimensional Problems
Authors: Mardochée Magolu Monga-Made, Yvan Notay
Venue: SIAM Journal on Scientific Computing (1999)

To efficiently solve second-order discrete elliptic PDEs by Krylov subspace-like methods, one needs to use some robust preconditioning techniques. Relaxed incomplete factorizations (RILU) are powerful candidates.\ Unfortunately, their efficiency critically depends on the choice of the relaxation parameter $\omega$ whose "optimal" value is not only hard to estimate but also strongly varies from one problem to another. These methods interpolate between the popular ILU and its modified variant (MILU). Concerning the pointwise schemes, a new variant of RILU that dynamically computes variable $\omega=\omega_i$ has been introduced recently. Like its ancestor RILU and unlike standard methods, it is robust with respect to both existence and performance. On top of that, it breaks the problem-dependence of ``$\omega_{opt}$."\ A block version of this dynamically relaxed method is proposed and compared with classical pointwise and blockwise methods as well as with some existing "dynamic" variants, showing that with the new blockwise preconditioning technique, anisotropies are handled more effectively.
A comparative study of two Boolean formulations of FPGA detailed routing constraints
Authors: Gi-Joon Nam, Fadi Aloul, Karem Sakallah, Rob Rutenbar
Venue: Proceedings of the 2001 international symposium on Physical design (2001)

A Boolean-based router expresses the routing constraints as a Boolðean function which is satisfiable if and only if the layout is routable. Compared to traditional routers, Boolean-based routers offer two unique features: (1) simultaneous embedding of all nets regardless of net ordering, and (2) ability to demonstrate routing infeasibility by proving the unsatisfiability of the generated routing constraint Boolean function. In this paper, we introduce a new Boolean-based FPGA detailed routing formulation that yields an easy-to-evaluate and more scalable routability Boolean function than the previous methods. The routability constraints are expressed in terms of a set of route variables each of which designating a specific detailed route for a given net. Experimental results clearly show the superiðority of this formulation over an earlier formulation that expressed the constraints in terms of track variables.
Uniprocessor Virtual Memory without TLBs
Authors: Bruce Jacob, Trevor Mudge
Venue: IEEE Transactions on Computers (2001)

We present a feasibility study for performing virtual address translation without specialized translation hardware. Removing address translation hardware and instead managing address translation in software has the potential to make the processor design simpler, smaller, and more energy-efficient at little or no cost in performance. The purpose of this study is to describe the design and quantify its performance impact. Trace-driven simulations show that software-managed address translation is just as efficient as hardware-managed address translation. Moreover, mechanisms to support such features as shared memory, superpages, fine-grained protection, and sparse address spaces can be defined completely in software, allowing for more flexibility than in hardware-defined mechanisms.
Automatic abstracting and indexing&mdash;survey and recommendations
Authors: H. P. Edmundson, R. E. Wyllys
Venue: Communications of the ACM (1961)

In preparation for the widespread use of automatic scanners which will read documents and transmit their contents to other machines for analysis, this report presents a new concept in automatic analysis: the relative-frequency approach to measuring the significance of words, word groups, and sentences. The relative-frequency approach is discussed in detail, as is its application to problems of automatic indexing and automatic abstracting. Included in the report is a summary of automatic analysis studies published as of the date of writing. Conclusions are drawn that point toward more sophisticated mathematical and linguistic techniques for the solution of problems of automatic analysis.
Optimizing strategies for telescoping languages: procedure strength reduction and procedure vectorization
Authors: Arun Chauhan, Ken Kennedy
Venue: Proceedings of the 15th international conference on Supercomputing (2001)

At Rice University, we have undertaken a project to construct a framework for generating high-level problem solving languages that can achieve high performance on a variety of platforms.The underlying strategy, called telescoping languages, builds problem-solving systems from domain-specific libraries and scripting langauges. To accomplish this it extensively preanalyzes and transforms the library to produce a scripting language precompiler that optimizes library calls within the scripts as if they were primitives in the underlying language. A major technical issue is how to preoptimize a library for use in applications that are yet to be seen. To address this issue, we have conducted a study of applications written in Matlab by the signal processing group at Rice University. This has identified a collection of old and new optimizations that show promise for this particular domain. Two promising new optimizations are procedure vectorization and procedure strength reduction.The latter of these is particularly useful in this problem domain and we expect it to be just as applicable in other contexts as well. We report on the results of an exploration of the effectiveness of procedure strength reduction on three real Digital Signal Processing (DSP) applications. By transforming these programs according to the strategies described in this paper, we were able to achieve speedups ranging from 10 to 40 percent over the entire application &mdash; speedups for individual functions were even more dramatic.
Fast-Start: quick fault recovery in oracle
Authors: Tirthankar Lahiri, Amit Ganesh, Ron Weiss, Ashok Joshi
Venue: ACM SIGMOD Record (2001)

Availability requirements for database systems are more stringent than ever before with the widespread use of databases as the foundation for ebusiness. This paper highlights Fast-Start&trade; Fault Recovery, an important availability feature in Oracle, designed to expedite recovery from unplanned outages. Fast-Start allows the administrator to configure a running system to impose predictable bounds on the time required for crash recovery. For instance, fast-start allows fine-grained control over the duration of the roll-forward phase of crash recovery by adaptively varying the rate of checkpointing with minimal impact on online performance. Persistent transaction locking in Oracle allows normal online processing to be resumed while the rollback phase of recovery is still in progress, and fast-start allows quick and transparent rollback of changes made by uncommitted transactions prior to a crash.
Symbolic-interval cooperation in constraint programming
Authors: Laurent Granvilliers, Eric Monfroy, Frédéric Benhamou
Venue: Proceedings of the 2001 international symposium on Symbolic and algebraic computation (2001)

This paper surveys the field of cooperative constraint solving for a constraint programming perspective with an emphasis on combinations of symbolic and interval methods. On the one hand, symbolic methods provide adapted representations of the constraint expressions. On the other hand, interval methods compute verified enclosures of solution sets. Using cooperation of solvers, one can take advantage of both techniques in a unified framework: symbolic algorithms generally need to be combined with root extraction methods, and the efficiency of interval algorithms strongly depends on constraint expressions.
A lower bound on the average-case complexity of shellsort
Authors: Tao Jiang, Ming Li, Paul Vitányi
Venue: Journal of the ACM (JACM) (2000)

We demonstrate an &Ohgr;(pn1+1/p ) lower bound on the average-case running time (uniform distribution) of p-pass Shellsort. This is the first nontrivial general lower bound for average-case Shellsort.
The MicroGrid: a scientific tool for modeling computational gridsr
Authors: H. J. Song, X. Liu, D. Jakobsen, R. Bhagwan, X. Zhang, K. Taura, A. Chien
Venue: Proceedings of the 2000 ACM/IEEE conference on Supercomputing (CDROM) (2000)

The complexity and dynamic nature of the Internet (and the emerging Computational Grid) demand that middleware and applications adapt to the changes in configuration and availability of resources. However, to the best of our knowledge there are no simulation tools which support systematic exploration of dynamic Grid software (or Grid resource) behavior. We describe our vision and initial efforts to build tools to meet these needs. Our MicroGrid simulation tools enable Globus applications to be run in arbitrary virtual grid resource environments, enabling broad experimentation. We describe the design of these tools, and their validation on micro-benchmarks, the NAS parallel benchmarks, and an entire Grid application. These validation experiments show that the MicroGrid can match actual experiments within a few percent (2 percent to 4 percent).
Exclusive simulation of activity in digital networks
Authors: Ernst G. Ulrich
Venue: Communications of the ACM (1969)

A technique for simulating the detailed logic networks of large and active digital systems is described. Essential objectives sought are improved ease and economy in model generation, economy in execution time and space, and a facility for handling simultaneous activities. The main results obtained are a clear and useful separation of structural and behavioral model description, a reduction of manual tasks in converting Boolean logic into a structural model, the elimination of manual processes in achieving exclusive simulation of activity, an event-scheduling technique which does not deteriorate in economy as the event queue grows in length, and a simulation procedure which deals effectively with any mixture of serial and simultaneous activities. The passage of time is simulated in a precise, quantitative fashion, and systems to be simulated may be combinations of synchronous and asynchronous logic. Certain aspects of the techniques described may be used for the simulation of network structures other than digital networks.