ppxscal/embedding_network huggingface dataset:
Parallel simulation of queueing networks: limitations and potentials
Authors: D. B. Wagner, E. D. Lazowska
Venue: Proceedings of the 1989 ACM SIGMETRICS international conference on Measurement and modeling of computer systems (1989)

This paper concerns the parallel simulation of queueing network models (QNMs) using the conservative (Chandy-Misra) paradigm. Most empirical studies of conservative parallel simulation have used QNMs as benchmarks. For the most part, these studies concluded that the conservative paradigm is unsuitable for speeding up the simulation of QNMs, or that it is only suitable for simulating a very limited subclass of these models (e.g., those containing only FCFS servers). In this paper we argue that these are unnecessarily pessimistic conclusions. On the one hand, we show that the structure of some QNMs inherently limits the attainable simulation speedup. On the other hand, we show that QNMs without such limitations can be efficiently simulated using some recently introduced implementation techniques. We present an analytic method for determining an upper bound on speedup, and use this method to identify QNM structures that will exhibit poor simulation performance. We then survey a number of promising implementation techniques, some of which are quite general in nature and others of which apply specifically to QNMs. We show how to extend the latter to a larger class of service disciplines than had been considered previously.
A Microeconomic Approach to Optimal Resource Allocation in Distributed Computer Systems
Authors: James F. Kurose, Rahul Simha
Venue: IEEE Transactions on Computers (1989)

Decentralized algorithms are examined for optimally distributing a divisible resource in a distributed computer system. To study this problem in a specific context, the problem of optimal file allocation is considered. In this case, the optimization criteria include both the communication cost and average processing delay associated with a file access. The algorithms examined have their origins in the field of mathematical economics. They are shown to have several attractive properties, including their simplicity and distributed nature, the computation of feasible and increasingly better resource allocations as the result of each iteration, and, in the case of file allocation, rapid convergence. Conditions are formally derived under which the algorithms are guaranteed to coverage, and their convergence behavior is additionally examined through simulation.
An expert system for the selection of indexable inserts and tool holders
Authors: G. S. Sohal, O. K. Eyada
Venue: Proceedings of the 2nd international conference on Industrial and engineering applications of artificial intelligence and expert systems - Volume 1 (1989)

The selection and optimum utilization of tool holders and inserts is important for reducing manufacturing costs. The process of selection is time consuming and requires highly experienced process planners or tool engineers. This paper describes a Cutting Tool Expert system (CTE) developed to assist users in cutting tool selection or design. The system is implemented using the M.1 expert shell, runs on a personal computer. CTE queries the user on the type of operation, workpiece material and condition, tolerance, surface finish, etc. The system's recommendations are based on the ANSI/ISO specifications. CTE also suggests the appropriate cutting conditions for the selected insert.
Trace selection for compiling large C application programs to microcode
Authors: P. P. Chang, W. W. Hwu
Venue: Proceedings of the 21st annual workshop on Microprogramming and microarchitecture (1988)

Microcode optimization techniques such as code scheduling and resource allocation can benefit significantly by reducing uncertainties in program control flow. A trace selection algorithm with profiling information reduces the uncertainties in program control flow by identifying sequences of frequently invoked basic blocks as traces. These traces are treated as sequential codes for optimization purposes. Optimization based on traces is especially useful when the code size is large and the control structure is complicated enough to defeat hand optimizations. However, most of the experimental results reported to date are based on small benchmarks with simple control structures. For different trace selection algorithms, we report the distribution of control transfers categorized according to their potential impact on the microcode optimizations. The experimental results are based on ten C application programs which exhibit large code size and complicated control structure. The measured data for each program is accumulated across a large number of input files to ensure the reliability of the result. All experiments are performed automatically using our IMPACT C compiler which contains integrated profiling and analysis tools.
A New Region Expansion for Quadtrees
Authors: C.-H. Ang, H. Samet, C. A. Shaffer
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

A one-pass algorithm that performs region expansion in images represented by quadtrees is presented. The algorithm changes to black those white pixels within a specified distance of any black mode in the image. The algorithm yields a significant improvement over previous approaches by reducing both the number of black nodes that must be considered for expansion and the number of nodes that must be inserted as a result of the expansion. The reductions are achieved by introducing the concepts of a merging cluster and a vertex set. Empirical tests show that the execution time of this algorithm generally decreases as the radius of expansion increases, whereas in previous approaches the execution time generally increased with the radius of expansion.
Bayan: an Arabic text database management system
Authors: Roger King, Ali Morfeq
Venue: ACM SIGMOD Record (1990)

Most existing databases lack features which allow for the convenient manipulation of text. It is even more difficult to use them if the text language is not based on the Roman alphabet. The Arabic language is a very good example of this case. Many projects have attempted to use conventional database systems for Arabic data manipulation (including text data), but because of Arabic's many differences with English, these projects have met with limited success. In the Bayan project, the approach has been different. Instead of simply trying to adopt an environment to Arabic, the properties of the Arabic language were the starting point and everything was designed to meet the needs of Arabic, thus avoiding the shortcomings of other projects. A text database management system was designed to overcome the shortcomings of conventional database management systems in manipulating text data. Bayan's data model is based on an object-oriented approach which helps the extensibility of the system for future use. In Bayan, we designed the database with the Arabic text properties in mind. We designed it to support the way Arabic words are derived, classified, and constructed. Furthermore, linguistic algorithms (for word generation and morphological decomposition of words) were designed, leading to a formalization of rules of Arabic language writing and sentence construction. A user interface was designed on top of this environment. A new representation of the Arabic characters was designed, a complete Arabic keyboard layout was created, and a window-based Arabic user interface was also designed.
The effectiveness of error seeding
Authors: B. Meek, K. K. Siu
Venue: ACM SIGPLAN Notices (1989)

Randomised error seeding is a technique which can be used to evaluate the ability of language processors to detect and report errors in source programs. The advantages and disadvantages of the method are discussed, and various strategies for using it presented. The lessons learned from experiments in using it on selected Pascal and Prolog systems are summarised, and suggestions for further research are offered.
Network and nodal architectures for the internetworking between frame relaying services
Authors: Wai Sum Lai
Venue: ACM SIGCOMM Computer Communication Review (1989)

Frame relaying is a new CCITT-recommended packet mode bearer service in ISDNs for data communications. Its major characteristics are out-of-band call control and link layer multiplexing.Requirements for the interworking between frame relaying services are the support for a multi-network, multi-vendor environment, and the integration of call control. After a comparison of the service characteristics of packet switching, circuit switching, and frame relaying, we conclude that the inter-nodal interworking strategy meets these requirements better than the internetwork interworking strategy.To understand better the requirements of a network architecture for the provision of frame relaying service, and to lend support for the standardization of the inter-nodal interworking strategy, a preliminary view on the functional structure of a network node is presented.
Restructuring for Fault-Tolerant Systolic Arrays
Authors: H. F. Li, R. Jayakumar, C. Lam
Venue: IEEE Transactions on Computers (1989)

The problem of restructuring systolic arrays with faulty cells is considered. An approach to derive the required data-flow paths and computational sites is proposed. The data skewing requirement, which must be satisfied to find an input schedule, is also discussed. Algorithms to restructure systolic arrays for three different architectures of processing elements are presented. A systematic method to retime the restructured array using additional programmable delays so that the retimed array satisfies the data skewing requirements is developed.
An update measure of supervisor-rated job performance for programmer/analysis
Authors: D. K. Goldstein
Venue: Proceedings of the ACM SIGCPR conference on Management of information systems personnel (1988)

In this research an updated measure of job performance is proposed. The measure is based on the work of Arvey and Hoyle (1974) and is modified to meet the changes in MIS jobs over the last several years. The eighteen item job performance measure was given to 238 programmer/analysts and their supervisors at a large company. A factor analysis of the items yielded a five factor model of performance composed of: overall performance, communication skills, job attitude, business knowledge, and technical skills. The factors were found to be both reliable and valid. Relationships among the factors, and between the factors and both demographic variables and work satisfaction, are explored.
High precision electron beam positioning using computer image analysis for electron beam testing
Authors: John R. Michener
Venue: Microelectronic Engineering (1988)

High precision electron beam positioning has been implemented in an electron beam tester using a relatively inaccurate mechanical positioner, the xy electron column field shift coils, and an image analysis computer to control the system. This system compares the observed circuit area with a reference circuit layout and determines positioning error values which it then corrects. Positioning precisions of +/-0.1 micrometers are easily achieved.
Object oriented design in a real-time multiprocessor environment
Authors: K. McQuown
Venue: Proceedings of the conference on Tri-Ada '89: Ada technology in context: application, development, and deployment (1989)

Object Oriented Design (OOD), with its emphasis on data encapsulation and rigorously defined message passing interfaces, offers great possibilities for improving the reliability and maintainability of large-scale software. These improvements are made feasible for the first time in military avionics applications by the recent emergence of new computers with significant increases in processing power and memory capacity. Ironically, this newly available hardware, because it features modularity and multiprocessing, calls for distributed software, and thereby introduces an interesting challenge to the Object Oriented software view. The message passing or operation invoking interface between two objects which reside on the same processor is well defined and readily handled within the OOD paradigm. How to extend the paradigm to cover two objects hosted on two different processors requires some thought, since only data, not tasks, can be passed from one processor to another This distributed-objects challenge was faced early on in the development of Ada software for the F-16A/B VHSIC1 Core Avionics Processor (VCAP). This thirty month project, initiated in December 1987 by the Ogden Air Logistics Command (OO-ALC), is prototyping hardware and software for a possible Advanced Avionics Architecture (A3) upgrade to the F-16A/B Fire Control and Stores Management systems. The solution devised for VCAP is called the Remote Object Paradigm (ROP). This paper describes relevant features of the VCAP architecture and application, explains the ROP methodology, and presents performance statistics to show the adequacy of ROP to support hard real-time requirements.
Incremental radiosity: an extension of progressive radiosity to an interactive image synthesis system
Authors: Shenchang Eric Chen
Venue: Proceedings of the 17th annual conference on Computer graphics and interactive techniques (1990)

Traditional radiosity methods can compute the illumination for a scene independent of the view position. However, if any part of the scene geometry is changed, the radiosity process will need to be repeated from scratch. Since the radiosity methods are generally expensive computationally, the traditional methods do not lend themselves to interactive uses where the geometry is constantly changing. This paper presents a new radiosity algorithm to incrementally render scenes with changing geometry and surface attributes. In other words, the question to be asked is "What is the minimum recomputation I need to do if I turn off a light source, change the color of a surface, add or move an object?" Because a modeling change generally exhibits some coherence and affects only parts of an image, the proposed method may drastically reduce the rendering time and therefore allow interactive manipulation. In addition, since the method is conducted incrementally and view-independently, the rendering process can start before the modeling process is completed. The traditional paradigm of modeling-then-rendering is changed to rendering-while-modeling. This approach not only gives the user better visual feedback but also effectively utilizes CPU time otherwise wasted in the modeling process.
Computational limitations on learning from examples
Authors: Leonard Pitt, Leslie G. Valiant
Venue: Journal of the ACM (JACM) (1988)

The computational complexity of learning Boolean concepts from examples is investigated. It is shown for various classes of concept representations that these cannot be learned feasibly in a distribution-free sense unless R = NP. These classes include (a) disjunctions of two monomials, (b) Boolean threshold functions, and (c) Boolean formulas in which each variable occurs at most once. Relationships between learning of heuristics and finding approximate solutions to NP-hard optimization problems are given.
Modeling Light Reflection for Computer Color Vision
Authors: H.-C. Lee, E. J. Breneman, C. P. Schulte
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1990)

In computer vision applications, analysis of shading information requires a proper model of light reflection from object surfaces. To overcome the shortcoming of the most often used model and to extend the reflection model for computer color vision, an examination is made of the light reflection problem using the bidirectional spectral-reflectance distribution function (BSRDF) to specify both incident- and reflected-beam geometries. It is shown that the product form can still be retained for a polychromatic light source under two lighting conditions: the light source is collimated; or the spectral factor and the geometric factor can be separated for both the light source and the BSRDF of the surface. The reflection model is then applied to the formulation of a neutral-interface-reflection model, which is tested experimentally. The results show the adequacy of this type of model for surfaces of some material compositions, e.g. plastics, plant leaves, painted surfaces, orange peels, and some glossy cloth, but not for others, e.g. colored paper and some ceramics.
Optimum combinations of sorting and merging
Authors: G. K. Manacher, T. D. Bui, T. Mai
Venue: Journal of the ACM (JACM) (1989)

In 1979, G. K. Manacher showed that the Ford-Johnson sorting algorithm [FJA], acting on t real numbers, can be beaten for an infinite set of values t. These values form a partial cover of constant density not close to 1 over an initial sequence of each band running from uk = &lfloor;(4/3)2k&rfloor; to uk+l - 1. This early result depended on showing that the Hwang-Lin merging algorithm [HLA], merging m elements with n, m &ne; n, could be surpassed by cm comparisons, where c is an arbitrary small positive constant. In this paper, it is shown that the FJA can be beaten for a set of integers of asymptotic density 1 under the greatly weakened assumption that the HLA can be surpassed by only (1/2 + &egr;)log m comparisons, with &egr; a small positive constant. The even weaker assumption that no improvement in the HLA exists, but that an isolated value to exists for which the FJA can be surpassed by only (1 + &egr;)log to comparisons yields the same result. Only for a set of &ldquo;refractory&rdquo; integers of size about t1/2 in the neighborhood of each uk does the FJA fail to be beaten. All these results depend on a new technique for obtaining optimum sort-merge sequences for best-possible sorting given a merging method. The technique turns out to be amenable to precise asymptotic analysis. When the technique is applied using the most powerful known merging algorithm [Christen's], the density mentioned above is still 1, but islands of refractory points still remain, this time forming sets provably of size &THgr;(log2t) in the neighborhood of each uk. It is shown that if &ldquo;information theoretic&rdquo; merging were achievable, the FJA could be beaten for all t > u10 = 1365. From these results and a few others, we adduce evidence in support of our main conjecture: that even optimum combinations of optimum merging and Ford-Johnson sorting will not beat the FJA when t = uk, but will instead produce refractory regions of size &THgr;(log2t) in the neighborhood of each &lgr;.
Aladdin/lamp: Configuration management tools for distributed computer control systems
Authors: A. Pakstas
Venue: Proceedings of the 2nd International Workshop on Software configuration management (1989)

The problem of the automation of the development of distributed software configuration (DSC) in the distributed computer control systems (DCCS) is discussed. The present paper deals with the building technology of the organisation of the interactions environment of applicational programs through the constructions like &ldquo;information transport port&rdquo; (ITP); On the basis of the DCCS structural model the system architects' language ALADDIN is developed. It is designated for the control of ITP work and for the linkage of DSC. The ALADDIN/LAMP software development system is described.
Polynomial universal traversing sequences for cycles are constructible
Authors: Sorin Istrail
Venue: Proceedings of the twentieth annual ACM symposium on Theory of computing (1988)

The paper constructs the first polynomial universal traversing sequences for cycles, solving an open problem of S. Cook and R. Aleliunas, R. Karp, R. Lipton, L. Lovasz, C. Rackoff (1979) [2] in the case of 2-regular graphs. The existence of universal traversing sequences of size &Ogr;(d2n3logn) for n-vertex d-regular graphs was established in [2] by a probabilistic argument, which was inherently non-constructive. For the cycles, the non-constructive upper bound was improved to &Ogr; (n3) by Janowsky (1983) [13] and Cobham (1986) [8]. Previously, the best explicit constructions for cycles were due to Bridgland (1986) and A. Bar-Noy, A. Borodin, M. Karchmer, N. Linial, and M. Werman (1986), and have size &Ogr;(nlog n). Our universal traversing sequence has size &Ogr;(n4.76), and can be constructed in log-space.
An empirical approach to the evaluation of icons
Authors: J. M. Webb, P. F. Sorenson, N. P. Lyons
Venue: ACM SIGCHI Bulletin (1989)

This poster provides a definition and taxonomy for iconic communication and describes the use of formal psychological tools and methods in the evaluation of icons. The methods that can be usefully applied include:1. Psychophysics2. Scaling3. Recognition/Memory Testing4. Statistical Modeling/AnalysisExamples of some of these approaches are provided from pilot studies currently under way at HP. Analyses used include Multi-Dimensional Scaling (MDS) and Cluster analysis. Results can be applied to development of metrics, standard methods, and design guidelines.
A proposed college curriculum in simulation
Authors: Bevlee A. Watford, D. L. Kimbler
Venue: Proceedings of the 21st annual symposium on Simulation (1988)

The status of simulation education at Clemson University is investigated with respect to the current requirements of industry use of simulation as an analytical tool. A sequence of courses addressing all phases of the simulation analysis and modeling procedure is described. A taxonomy of simulation topics by area and curriculum level is provided. A survey of industry simulation analysts is utilized to assist in specifying the proposed educational requirements to ensure that Clemson industrial engineers are provided with adequate training.
Normal forms in function fields
Authors: K. Aberer
Venue: Proceedings of the international symposium on Symbolic and algebraic computation (1990)

We consider function fields of functions of one variable augmented by the binary operation of composition of functions. It is shown that the straightforward axiomatization of this concept allows the introduction of a normal form for expressions denoting elements in such fields. While the description of this normal form seems relatively intuitive, it is surprisingly difficult to prove this fact. We present an algorithm for the normalization of expressions, formulated in the symbolic computer algebra language mathematica. This allows us to effectively decide compositional identities in such fields. Examples are given.
Self-assessment procedure XX
Authors: J. Rosenberg, A. L. Ananda, B. Srinivasan
Venue: Communications of the ACM (1990)

A self-assessment procedure on operating systems
Experience with CST: programming and implementation
Authors: W. Horwat, A. A. Chien, W. J. Dally
Venue: ACM SIGPLAN Notices (1989)

CST is a programming language based on Smalltalk-802 that supports concurrency using locks, asynchronous messages, and distributed objects. In this paper, we describe CST: the language and its implementation. Example programs and initial programming experience with CST are described. Our implementation of CST generates native code for the J-machine, a fine-grained concurrent computer. Some compiler optimizations developed in conjunction with that implementation are also described.
Regular CC-banyan networks
Authors: D. W. Kim, G J. Lipovski, A. Hartmann, R. Jenevein
Venue: Proceedings of the 15th Annual International Symposium on Computer architecture (1988)

Construction algorithms for rectangular and nonrectangular CC-Banyan networks are presented. Routing algorithms for double and single-ended rectangular and non-rectangular CC-Banyan networks are also presented. The time complexities of the routing algorithms are O(l), where l is the number of stages in the network.
Sixth annual UCLA survey of business school computer usage
Authors: Jason L. Frand, Julia A. Britt
Venue: Communications of the ACM (1990)

Providing the most comprehensive picture to date of the business school computing, communication, and information environment, this year's survey extends the focus of the Fourth Survey (1987) and raises the question: how to most effectively manage these resources.