ppxscal/embedding_network huggingface dataset:
Consulting Revealed
Authors: Joshua Drake
Venue: Linux Journal (2001)

Joshua gives an honest and thorough profile of the range of consultants.
Remark on uniform insertion in structured data structures
Authors: Clifford R. Hollander
Venue: Communications of the ACM (1977)

In a recent paper, Shneiderman and Scheuermann [1] have defined an interesting operation, called uniform insertion, whereby a (linked) data structure G2 can be embedded within another structure G1 in such a way that each data node of G1 serves as an entry node for G2. This communication points out and corrects an error in their definition, while preserving the spirit of that operation.
Use petri nets to improve your concurrent programming course (poster session)
Authors: João Paulo Barros
Venue: ACM SIGCSE Bulletin (2001)

Petri nets are recommended as a learning aid in a concurrent programming course covering modelling and verification techniques, based on state space analysis, and translation of formal models to Java programs.
Improving the quality of compiler construction with object-oriented techniques
Authors: David Basanta Gutiérrez, Cándida Luengo Díez, Raul Izquierdo Castanedo, Jose Emilio Labra Gayo, Juan Manuel Cueva
Venue: ACM SIGPLAN Notices (2000)

Compiler construction tools have proven to be very useful for developers in the traditional task of compiler construction and language processors that are present in editors, word processors or XML. In contrast to their importance, traditional tools like YACC have failed to take advantage of object-oriented techniques. This is particularly unfortunate because compilers, being complex systems, would definitely benefit from the modularity and code reuse that object orientation allows.In this paper, O2C2, an object-oriented framework generator, is presented. The tool has the potential to improve the quality of compiler construction by introducing the concept of frameworks in the field of compilers and language processors.
A learning by doing model for teaching advanced databases
Authors: M. V. Ramakrishna
Venue: Proceedings of the Australasian conference on Computing education (2000)

This paper presents a new model for teaching database subject and its evaluated outcomes, in the context of Australian undergraduate education. The model is aimed at motivating students to participate in active learning or learning by doing. In addition to the regular assessments, students were given regular homework to complete as a apart of sessional assessments. These homework were designed to be in tune with learning objectives of the subject. The tutors are assigned the task of marking and providing consultation help to the students, thus no extra resources are required for the new model. This model has been well received by the students with 87% of the students expressing preference to this model over the traditional model of tutorials. There is also strong evidence, specially from the examination answers of the students, that the new model has resulted in better accomplishment of the learning outcomes as compared to the traditional model.
Disk file sorting
Authors: Thomas Schick
Venue: Communications of the ACM (1963)

Use of the &ldquo;building-block&rdquo; type of approach suggested in [1] is heartily recommended. It has been used by our computer center for over a year with excellent results.
UpdateSearch: A New Dynamic Channel Allocation Scheme for Mobile Networks That Can Adjust to System Loads
Authors: Sandeep K. S. Gupta, Pradip K. Srimani
Venue: The Journal of Supercomputing (2000)

Distributed dynamic channel allocation techniques are an integral part of distributed mobile computing systems where nodes communicate among themselves via wireless radio channels. The channel allocation schemes can be broadly categorized as search based or update based. Search based techniques have low messaging complexity and are suited for high system load and low request rates. On the other hand update based schemes have higher messaging complexity but are more suitable for low system load and high request rates. This paper presents a combined scheme, called UpdateSearch, which provides the advantages of both types of schemes. UpdateSearch is parameterized by the number of channel classes k, 1&le;k&le;n, where n is the total number of channels in the system. The parameter k can be adjusted to control the number of concurrent searches and degree of contention between cells competing for channels in the system. For k&equals;1 and k&equals;n the scheme respectively behaves as basic search and basic update scheme &lsqb;2&rsqb;. A simple analytical model is used to compare the performance of UpdateSearch for various values of k with the basic update and search techniques in terms of channel allocation time and number of simultaneous channel selections allowed in the system under different system loading conditions.
A novel parallel deadlock detection algorithm and architecture
Authors: Pun H. Shiu, YuDong Tan, Vincent J. Mooney,  III
Venue: Proceedings of the ninth international symposium on Hardware/software codesign (2001)

A novel deadlock detection algorithm and its hardware implementation are presented in this paper. The hardware deadlock detection algorithm has a run time complexity of &Ogr;hw (min(m,n)), where m and n are the number of processors and resources, respectively. Previous algorithms based on a Resource Allocation Graph have &Ogr;sw (m &times; n) run time complexity for the worst case. We simulate a realistic example in which the hardware deadlock detection unit is applied, and demonstrate that the hardware implementation of the novel deadlock detection algorithm reduces deadlock detection time by 99.5%. Furthermore, in a realistic example, total execution time is reduced by 68.9%.
Parallel algorithms for radiation transport on unstructured grids
Authors: Steve Plimpton, Bruce Hendrickson, Shawn Burns, Will McLendon,  III
Venue: Proceedings of the 2000 ACM/IEEE conference on Supercomputing (CDROM) (2000)

The method of discrete ordinates is commonly used to solve the Boltzmann radiation transport equation for applications ranging from simulations of fires to weapons effects. The equations are most efficiently solved by sweeping the radiation flux across the computational grid. For unstructured grids this poses several interesting challenges, particularly when implemented on distributed-memory parallel machines where the grid geometry is spread across processors. We describe an asynchronous, parallel, message-passing algorithm that performs sweeps simultaneously from many directions across unstructured grids. We identify key factors that limit the algorithm's parallel scalability and discuss two enhancements we have made to the basic algorithm: one to prioritize the work within a processor's subdomain and the other to better decompose the unstructured grid across processors. Performance results are given for the basic and enhanced algorithms implemented within a radiation solver running on hundreds of processors of Sandia's Intel Tflops machine and DEC-Alpha CPlant cluster.
Computer assisted instruction: current trends and critical issues
Authors: Jack A. Chambers, Jerry W. Sprecher
Venue: Communications of the ACM (1980)

The use of computers to assist in the learning situation in a simulation, game, tutorial, or drill and practice mode is reviewed on an international basis with centers of activity identified in the United States, Canada, the United Kingdom, and Japan. The use of the computer as an adjunct to support learning is compared to its use in a substitution mode. Evaluative studies of CAI are reviewed and costs are examined. The critical issues of CAI are enumerated and analyzed as they pertain to computer hardware, CAI languages, and courseware development and use. The future of CAI is briefly sketched from the viewpoints of individuals prominent in the field. Finally, conclusions are drawn and recommendations are offered to help ensure the most educationally cost-effective use of CAI in learning situations.
Computer graphics education directory
Authors: Steve Cunningham
Venue: ACM SIGGRAPH Computer Graphics (1985)

This is SIGGRAPH's second directory of college-level computer graphics education, covering courses in computer graphics in a broad spectrum of disciplines. This directory is a single source of computer graphics course information. If you are a student entering college or considering a change of studies, a professional considering broadening your skills, or an educator seeking broader contacts in graphics among your peers, this directory is designed for you.The directory was compiled from the first directory and responses to a questionnaire sent out last spring. These responses were divided up by topic according to information received on the questionnaire and our perception of the course's audience. The placement of some courses may not be precise, so you may be advised to use more than one directory list in your search. For example, someone interested in graphics for architects would consult the Arts, Architecture, and Design listings, but might also find useful information in the list on Engineering, CAD/CAM, and Drafting. All interesting entries should be followed up by direct contact with the school for the many details of schedule, cost, and admission which are not included here.The courses we received were placed in individual lists by the following criteria. The Concepts and Systems list consists of courses covering general concepts in computer graphics and systems for producing graphics; such courses are often found in Computer Science or EECS programs and have no particular application orientation. The Engineering, CAD/CAM, and Drafting list contains courses which seem to be oriented toward applications in these areas. For CAD/CAM and Drafting courses, this is rather easy to tell, while the engineering orientation is inferred from a location in an Engineering program with no other information, or from a title such as "Engineering Computer Graphics." Many Engineering programs, however, have courses which seem to fit the Concepts and Systems category most closely and so are listed there. The other lists are fairly easily categorized, except for some problems determining where to place courses in Design; here the home program is usually the determining factor.
The membership problem for ideals of binomial skew polynomial rings
Authors: Liu Jinwang, Liu Zhuojun, Liu Xiaoqi, Wang Mingsheng
Venue: Proceedings of the 2001 international symposium on Symbolic and algebraic computation (2001)

In this paper, the authors study binomial skew polynomial ring A. We can find a Gr&ouml;bner basis of a two-sided ideal (as left ideal). Thus, we solve the question 2 in [2]: Is it true that A has a decidable membership problem for finitely generated two-sided ideals?
Constraint Preconditioning for Indefinite Linear Systems
Authors: Carsten Keller, Nicholas I. M. Gould, Andrew J. Wathen
Venue: SIAM Journal on Matrix Analysis and Applications (2000)

The problem of finding good preconditioners for the numerical solution of indefinite linear systems is considered. Special emphasis is put on preconditioners that have a 2 &times; 2 block structure and that incorporate the (1,2) and (2,1) blocks of the original matrix. Results concerning the spectrum and form of the eigenvectors of the preconditioned matrix and its minimum polynomial are given. The consequences of these results are considered for a variety of Krylov subspace methods. Numerical experiments validate these conclusions.
Computing standard deviations: accuracy
Authors: Tony F. Chan, John Gregg Lewis
Venue: Communications of the ACM (1979)

Four algorithms for the numerical computation of the standard deviation of (unweighted) sampled data are analyzed. Two of the algorithms are well-known in the statistical and computational literature; the other two are new algorithms specifically intended for automatic computation. Our discussion is expository, with emphasis on reaching a suitable definition of &ldquo;accuracy.&rdquo; Each of the four algorithms is analyzed for the conditions under which it will be accurate. We conclude that all four algorithms will provide accurate answers for many problems, but two of the algorithms, one new, one old, are substantially more accurate on difficult problems than are the other two.
Overlap matching
Authors: Amihood Amir, Richard Cole, Ramesh Hariharan, Moshe Lewenstein, Ely Porat
Venue: Proceedings of the twelfth annual ACM-SIAM symposium on Discrete algorithms (2001)

We propose a new paradigm for string matching, namely structural matching. In structural matching, the text and pattern contents are not important. Rather, some areas in the text and patterns are singled out, say intervals. A &ldquo;match&rdquo; is a text location where a specified relation between the text and pattern areas is satisfied. In particular we define the structural matching problem of Overlap (Parity) Matching. We seek the text locations where all overlaps of the given pattern and text intervals have even length. We show that this problem can be solved in time &Ogr;(n log m), where the text length is n and the pattern length is m. As an application of overlap matching, we show how to reduce the String Matching with Swaps problem to the overlap matching problem. The String Matching with Swaps problem is the problem of string matching in the presence of local swaps. The best known deterministic upper bound for this problem was &Ogr;(nm1/3 log m log &sgr;) for a general alphabet &sum;, where &sgr; = min(m, &brvbar;&sum;&brvbar;). Our reduction provides a solution to the pattern matching with swaps problem in time &Ogr;(n log m log &sgr;).
A pipelined architecture for partitioned DWT based lossy image compression using FPGA's
Authors: Jörg Ritter, Paul Molitor
Venue: Proceedings of the 2001 ACM/SIGDA ninth international symposium on Field programmable gate arrays (2001)

Discrete wavelet transformations (DWT) followed by embedded zerotree encoding is a very efficient technique for image compression \cite{TenLectures, Shapiro, Spiht}. However, the algorithms proposed in literature assume random access to the whole image. This makes the algorithms unsuitable for hardware solutions because of extensive access to external memory. Here, we present an efficient architecture for computing DWT of images, which is based on a partitioned approach for lossy image compression~\cite{Ritter}. The architecture achieves its computational power by using pipelining and taking advantage of the flexible memory configurations available in FPGA's.
BLISS: a language for systems programming
Authors: W. A. Wulf, D. B. Russell, A. N. Habermann
Venue: Communications of the ACM (1971)

A language, BLISS, is described. This language is designed so as to be especially suitable for use in writing production software systems for a specific machine (the PDP-10): compilers, operating systems, etc. Prime design goals of the design are the ability to produce highly efficient object code, to allow access to all relevant hardware features of the host machine, and to provide a rational means by which to cope with the evolutionary nature of systems programs. A major feature which contributes to the realization of these goals is a mechanism permitting the definition of the representation of all data structures in terms of the access algorithm for elements of the structure.
A Software-Reuse Approach to Build Monitor Programs forSoft Real-Time Applications
Authors: Tei-Wei Kuo, Mei-Ling Hsu
Venue: Real-Time Systems (2000)

This paper describes the implementation of an integration framework to build real-time monitor programs based on software reuse. A custom-made real-time monitor program can be built very quickly by integrating existing monitor programs on commercial operating systems, where limited real-time system support is provided. We address issues related to software control, output re-processing, data age, and interactivities of program executions. The feasibility of this framework is demonstrated by the construction of an integration environment and a monitor program built by the environment for soft real-time applications in the Microsoft Windows operating systems. We also measure the incurred system overheads of this approach.
An integrity constraints driven system for updating spatial databases
Authors: Alberto Belussi, Mauro Negri, Giuseppe Pelagatti
Venue: Proceedings of the 8th ACM international symposium on Advances in geographic information systems (2000)

This paper describes a prototypal system which has been implemented in order to explore the possibility of using topological integrity constraints as interactive drivers to support spatial database updates. The idea of using constraints to drive updates is applied also in traditional (non-spatial) databases; for example, in order to preserve referential integrity, the user can be forced to select a value in a given set, instead of permitting him to write an arbitrary value and then checking that the value satisfies the constraint. This idea seems to be much more relevant in spatial databases, both because spatial data possesses a much richer set of constraints, and because spatial updates are more complex and error-prone than traditional, alphanumeric updates. The paper first defines formally a rather general spatial database environment with integrity constraints, then describes a prototypal system which has been built in order to explore the practical effectiveness of the general idea (the feasibility includes performance, because the constraints are used during the interaction with the user). The prototype which has been implemented is capable of driving updates on simple polygons and uses a restricted class of integrity constraints; however, it is sufficiently powerful to demonstrate the feasibility of the approach.
A reply to gentleman and Marovich
Authors: Richard Alan Karp
Venue: Communications of the ACM (1975)

Gentleman and Marovich in their short communication [Comm. ACM 17, 5 (May 1974) 276-277] make the claim that for FORTRAN &ldquo;&hellip; the language definitions require that subprograms can be separately compiled&hellip;,&rdquo; citing the ANSI FORTRAN standard X3.9-1966 as their authority.
Restructuring Partitioned Normal Form Relations without Information Loss
Authors: Millist W. Vincent., Mark Levene
Venue: SIAM Journal on Computing (2000)

Nested relations in partitioned normal form (PNF) are an important subclass of nested relations that are useful in many applications. In this paper we address the question of determining when every PNF relation stored under one nested relation scheme can be transformed into another PNF relation stored under a different nested relation scheme without loss of information, referred to as the two schemes being data equivalent. This issue is important in many database application areas such as view processing, schema integration, and schema evolution. The main result of the paper provides two characterizations of data equivalence for nested schemes. The first is that two schemes are data equivalent if and only if the two sets of multivalued dependencies induced by the two corresponding scheme trees are equivalent. The second is that the schemes are equivalent if and only if the corresponding scheme trees can be transformed into the other by a sequence of applications of a local restructuring operator and its inverse.
On the Solution Sets of Linear Complementarity Problems
Authors: G. S. R. Murthy, T. Parthasarathy, B. Sriparna
Venue: SIAM Journal on Matrix Analysis and Applications (2000)

In this article we consider two problems related to the solution sets of linear complementarity problems (LCPs)---one on the connectedness and the other on the convexity. In Jones and Gowda [ Linear Algebra Appl., 246 (1996), pp. 299--312], it was shown that the solution sets of LCPs arising out of $P_0 \cap Q$-matrices are connected, and they conjectured that this is true even in the case of $P_0\ \cap\ Q_0$-matrices. We verify this, at least in the case of nonnegative matrices. Our second problem is related to the class of fully copositive $(C_0^f)$-matrices introduced in Murthy and Parthasarathy [ Math. Programming, 82 (1998), pp. 401--411]. The class $C_0^f\cap Q_0,$ which contains the class of positive semidefinite matrices, has several properties that positive semidefinite matrices have. This article further supplements this by showing that the solution sets arising from LCPs with $C_0^f\cap Q_0$-matrices and their transposes are convex. This means that $C_0^f\cap Q_0$-matrices are sufficient matrices, another well known class in the theory of linear complementarity problem introduced by Cottle, Pang, and Venkateswaran [ Linear Algebra Appl., 114/115 (1989), pp. 231--249].
Multiresolution curve editing with linear constraints
Authors: Gershon Elber
Venue: Proceedings of the sixth ACM symposium on Solid modeling and applications (2001)

The use of multiresolution control toward the editing of freeform curves and surfaces has already been recognized as a valuable modeling tool [4, 8, 11]. Similarly, in contemporary computer aided geometric design, the use of constraints to precisely prescribe freeform shape is considered an essential capability [7, 18]. This paper presents a scheme that combines multiresolution control with linear constraints into one framework, allowing one to perform multiresolution manipulation of nonuniform B-spline curves, while specifying and satisfying various linear constraints on the curves. Positional, tangential, and orthogonality constraints are all linear and can be easily incorporated into a multiresolution freeform curve editing environment, as will be shown. Moreover, we also show that the symmetry as well as the area constraints can be reformulated as linear constraints and similarly incorporated. The presented framework is extendible and we also portray this same framework in the context of freeform surfaces.
A note on the expected distribution of degrees in random binary trees
Authors: Jarmo Siltaneva, Erkki Mäkinen
Venue: ACM SIGCSE Bulletin (2000)

We derive the expected numbers of nodes with 0, 1, and 2 children in random binary trees by using only elementary methods and concepts.
A comparison between the polyphase and oscillating sort techniques
Authors: Martin A. Goetz, Gloria S. Toth
Venue: Communications of the ACM (1963)

Read-backward Polyphase sorting provides more efficient use of the tapes available to a sort than most other sorting techniques. Backward Polyphase produces a continuous merging process from n - 1 tapes where n is the total number of tapes being used in the sorting process. Any of the available presorting techniques may be used in conjunction with the Polyphase merge sort provided that the presort has the capability of producing both ascending and descending strings and distributing the strings on the various tapes as required by the Polyphase Merge.