ppxscal/embedding_network huggingface dataset:
Applications of simulation in progress reporting and control
Authors: Nader N. Chehayeb, Simaan M. AbouRizk
Venue: Proceedings of the 27th conference on Winter simulation (1995)

Describes the development of the SimCon (SIMulation-based project CONtrol) system, which provides the basis for implementing progress reporting and control in a simulation model. The issues considered in SimCon include developing a reporting-by-exception capability from a hierarchical breakdown structure that minimizes progress reporting at the very detailed level. Simulation constructs are developed to store project progress information and simplify the logical linking of simulation processes. SimCon is implemented using object-oriented concepts, event-driven programming, relational databases and a simulation engine. The objective of this research is to improve construction management productivity in progress reporting and control and to improve decision-making by incorporating detailed resource-level interactions in project modeling.
Time-constrained code compaction for DSPs
Authors: Rainer Leupers, Peter Marwedel
Venue: Proceedings of the 8th international symposium on System synthesis (1995)

Abstract: DSP algorithms are, in most cases, subject to hard real-time constraints. In the case of programmable DSPs, meeting those constraints must be ensured by appropriate code generation techniques. For processors offering instruction-level parallelism, the task of code generation includes code compaction. The exact timing behavior of a DSP program is only known after compaction. Therefore, real-time constraints should be taken into account during the compaction phase. While most known DSP code generators rely on rigid heuristics for that phase, this paper proposes a novel approach to local code compaction based on an integer programming model, which obeys exact timing constraints. Due to a general problem formulation, the model also obeys encoding restrictions and possible side-effects.
Easily Checked Generalized Self-Reducibility
Authors: Lane A. Hemaspaandra, Riccardo Silvestri
Venue: SIAM Journal on Computing (1995)

This paper explores two generalizations within NP of self-reducibility: Arvind and Biswas's kernel constructibility and Khadilkar and Biswas's committability. Informally stated, kernel constructible sets have (generalized) self-reductions that are easy to check, though perhaps hard to compute, and committable sets are those sets for which the potential correctness of a partial proof of set membership can be checked via a query to the same set (that is, via a self-reduction). We study these two notions of generalized self-reducibility on non-dense sets. We show that sparse kernel constructible sets are of low complexity, we extend previous results showing that sparse committable sets are of low complexity, and we provide structural evidence of interest in its own right---namely that if all sparse disjunctively self-reducible sets are in P then $\fewp \,\cap\, \cofewp$ is not P-bi-immune---that our extension is unlikely to be further extended. We obtain density-based sufficient conditions for kernel-constructibility: sets whose complements are captured by non-dense sets are perforce kernel constructible. Using sparse languages and Kolmogorov complexity theory as tools, we argue that kernel constructibility is orthogonal to standard notions of complexity.
Conditional attribute grammars
Authors: John Tang Boyland
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1996)

Attribute grammars are a useful formalism for the specification of computations on structured terms. The classical definition of attribute grammars, however, has no way of treating conditionals nonstrictly. Consequently, the natural way of expressing many otherwise well-behaved computations involves a circularity. This article presents conditional attribute grammars, and extension of attribute grammars that enables more precise analysis of conditionals. In conditional attribute grammars, attribute equations may have guards. Equations are active only when their guards are satisfied. The standard attribute grammar evaluation classes are definable for conditional attribute grammars, and the corresponding evaluation techniques can be easily adapted. However, determining membership in standard evaluation classes such as 1-SWEEP, OAG, and SNC is NP-hard.
PC notes
Authors: Gene Styer
Venue: ACM SIGICE Bulletin (1995)

Welcome to a new series regarding IBM PC and compatible internals and details about how they operate. This has started as the result of a new class we offered, "Microcomputer Architecture and Software," which was intended to provide background that is both broad and detailed on the insides of a PC for high-school teachers, who will often be expected to be the 'computer wizard' at their respective schools. Because of this unusual combination of breadth and depth, we could not find a single acceptable book, and are relying on a set of reference books and class notes. This series will be based on those class notes.
Fundamental limits and tradeoffs of providing deterministic guarantees to VBR video traffic
Authors: Edward W. Knightly, Dallas E. Wrege, Jörg Liebeherr, Hui Zhang
Venue: Proceedings of the 1995 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems (1995)

Compressed digital video is one of the most important traffic types in future integrated services networks. However, a network service that supports delay-sensitive video imposes many problems since compressed video sources are variable bit rate (VBR) with a high degree of burstiness. In this paper, we consider a network service that can provide deterministic guarantees on the minimum throughput and the maximum delay of VBR video traffic. A common belief is that due to the burstiness of VBR traffic, such a service will not be efficient and will necessarily result in low network utilization. We investigate the fundamental limits and tradeoffs in providing deterministic performance guarantees to video and use a set of 10 to 90 minute long MPEG-compressed video traces for evaluation. Contrary to conventional wisdom, we are able to show that, in many cases, a deterministic service can be provided to video traffic while maintaining a reasonable level of network utilization. We first consider an ideal network environment that employs the most accurate deterministic, time-invariant video traffic characterizations, Earliest-Deadline-First packet schedulers, and exact admission control conditions. The utilization achievable in this situation provides the fundamental limits of a deterministic service. We then investigate the utilization limits in a network environment that takes into account practical constraints, such as the need for fast policing mechanisms, simple packet scheduling algorithms, and efficient admission control tests.
LEDA: a platform for combinatorial and geometric computing
Authors: Kurt Mehlhorn, Stefan Näher
Venue: Communications of the ACM (1995)

Combinatorial and geometric computing is a core area of computer science (CS). In fact, most CS curricula contain a course in data structures and algorithms. The area deals with objects such as graphs, sequences, dictionaries, trees, shortest paths, flows, matchings, points, segments, lines, convex hulls, and Voronoi diagrams and forms the basis for application areas such as discrete optimization, scheduling, traffic control, CAD, and graphics. There is no standard library of the data structures and algorithms of combinatorial and geometric computing. This is in sharp contrast to many other areas of computing. There are, for example, packages in statistics (SPSS), numerical analysis (LINPACK, EISPACK), symbolic computation (MAPLE, MATHEMATICA), and linear programming (CPLEX).
Optimal and Suboptimal Processor Allocation for Hypercycle-based Multiprocessors
Authors: Nikitas J. Dimopoulos, Vassilios V. Dimakopoulos
Venue: IEEE Transactions on Parallel and Distributed Systems (1995)

Allocating nodes in a concurrent computer system depends on the topology of the system. In this work, we present a number of processor allocation strategies for Hypercycle based concurrent systems. Hypercycles is a class of multidimensional interconnection networks which includes such widely used networks as the binary $n$-cubes, $k$-ary $n$-cubes, generalized hypercubes etc. The allocation strategies presented include a statically optimal first-fit allocation, a suboptimal-first fit, and strategies with extended search space through the inclusion of additional search lists formed by permuting the base through which a hypercycle is defined. For all these strategies, we examine their optimality and present simulation results characterizing their performance relative to each other.
From reuse library experiences to application generation architectures
Authors: Stan Jarzabek
Venue: ACM SIGSOFT Software Engineering Notes (1995)

Reuse through application generators has been successful in the area of programming language systems. We analyzed three language system projects that realized transition from the initial ad hoc programs, through libraries of reusable modules to application generator solutions. We tried to understand the underlying thinking process and technical factors that made such a transition possible. Based on this study, we generalized reuse experiences gained in the language system domain and formulated a reuse implementation framework. Our framework is to facilitate transition from component-based reuse to application generators in other domains. Ultimately, we hope our framework will offer reuse implementation guidelines for companies to realize such a transition. Initial findings are described in this paper.
Taxila: a digital library of research in document analysis and recognition
Authors: Debashish Niyogi, Sargur N. Srihari
Venue: ACM SIGWEB Newsletter (1995)

Only a few short years ago the hypertext community consisted of a [somewhat] small and highly-focused group of scientists who met every other year to discuss and share their results and advancements in systems, interface, human cognition, standards, rhethoric, applications, and methodology. Although an occasional outsider might venture to the conferences or perhaps read from the literature, there was a fairly clear distinction between the hypertext field and others.
FORTRAN codes for estimating the one-norm of a real or complex matrix, with applications to condition estimation
Authors: Nicholas J. Higham
Venue: ACM Transactions on Mathematical Software (TOMS) (1988)

FORTRAN 77 codes SONEST and CONEST are presented for estimating the 1-norm ( or the infinity-norm) of a real or complex matrix, respectively. The codes are of wide applicability in condition estimation since explicit access to the matrix, A, is not required; instead, matrix-vector products Ax and ATx are computed by the calling program via a reverse communication interface. The algorithms are based on a convex optimization method for estimating the 1-norm of a real matrix devised by Hager. We derive new results concerning the behavior of Hager's method, extend it to complex matrices, and make several algorithmic modifications in order to improve the reliability and efficiency.
A tutorial on PROSIM: a knowledge-based simulation model design tool
Authors: Madhavi Lingineni, Bruce Caraway, Perakath C. Benjamin, Richard J. Mayer
Venue: Proceedings of the 27th conference on Winter simulation (1995)

The paper introduces ProSim, a knowledge based simulation design tool that automatically generates simulation models from process models. Domain experts who are familiar with the various aspects of the system may be interviewed and process models can be developed based on the evidence collected using ProSim. The built-in simulation design support environment of ProSim enables building simulation models automatically from process models. A purchase order processing system example is described to demonstrate the utility of ProSim.
Gigabit I/O for distributed-memory machines: architecture and applications
Authors: Michael Hemy, Peter Steenkiste
Venue: Proceedings of the 1995 ACM/IEEE conference on Supercomputing (CDROM) (1995)

Distributed-memory systems have traditionally had great difficulty performing network I/O at rates proportional to their computational power. The problem is that the network interface has to support network I/O for a supercomputer, using computational and memory bandwidth resources similar to those of a workstation. As a result, the network interface becomes a bottleneck. We implemented an architecture for network I/O for the iWarp system with the following two key characteristics: first, application-specific tasks are off-loaded from the network interface to the distributed-memory system, and second, these tasks are performed in close cooperation with the application. The network interface has been used by several applications for over a year. In this paper we describe the network interface software that manages the communication between the iWarp distributed-memory system and the network interface, we validate the main features of our network interface architecture based on application experience, and we discuss how this architecture can be used by other distributed-memory systems.
A Globally Convergent Successive Approximation Method for Severely Nonsmooth Equations
Authors: Liqun Qi, Xiaojun Chen
Venue: SIAM Journal on Control and Optimization (1995)

This paper presents a globally convergent successive approximation method for solving $F(x)=0$ where $F$ is a continuous function. At each step of the method, $F$ is approximated by a smooth function $f_{k},$ with $\pa f_{k}-F\pa \rightarrow 0$ as $k \rightarrow \infty$. The direction $-f'_{k}(x_{k})^{-1}F(x_{k})$ is then used in a line search on a sum of squares objective. The approximate function $f_k$ can be constructed for nonsmooth equations arising from variational inequalities, maximal monotone operator problems, nonlinear complementarity problems, and nonsmooth partial differential equations. Numerical examples are given to illustrate the method.
Melding structured abstracts and World Wide Web for retrieval of reusable components
Authors: Jeffrey S. Poulin, Keith J. Werkman
Venue: ACM SIGSOFT Software Engineering Notes (1995)

Reusable Software Libraries (RSLs) often suffer from poor interfaces, too many formal standards, high levels of training required for their use, and most of all, a high cost to build and maintain. Hence, RSLs have largely failed to return the reuse benefits promised by their developers. This paper first describes an RSL implementation using the World Wide Web (WWW) browser Mosaic and shows how it meets most RSL needs, avoids most RSL pitfalls, and costs only a fraction of the cost for the average commercial RSL. Second, the paper describes a way to quickly assess the important aspects of a piece of software so programmers can decide whether or not to reuse it. Using the observation that when programmers discuss software they tend to convey the same key information in a somewhat predictable order, this paper describes a method to automatically mimic this activity using a Structured Abstract of reusable components. Structured Abstracts provide a natural, easy to use way for developers to (1) search for components, (2) quickly assess the component for use, and (3) submit components to the RSL.
Linear Algorithms for Partitioning Embedded Graphs of BoundedGenus
Authors: L. Aleksandrov, H. Djidjev
Venue: SIAM Journal on Discrete Mathematics (1996)

This paper develops new techniques for constructing separators for graphs embedded on surfaces of bounded genus. For any arbitrarily small positive $\varepsilon$ we show that any $n$-vertex graph $G$ of genus $g$ can be divided in $O(n+g)$ time into components whose sizes do not exceed $\varepsilon n$ by removing a set $C$ of $O(\sqrt{(g+1/\varepsilon)n})$ vertices. Our result improves the best previous ones with respect to the size of $C$ and the time complexity of the algorithm. Moreover, we show that one can cut off from $G$ a piece of no more than $(1-\varepsilon)n$ vertices by removing a set of $O(\sqrt{n\varepsilon (g\varepsilon +1})$) vertices. Both results are optimal up to a constant factor.
Efficient shared memory with minimal hardware support
Authors: Leonidas I. Kontothanassis, Michael L. Scott
Venue: ACM SIGARCH Computer Architecture News (1995)

Shared memory is widely regarded as a more intuitive model than message passing for the development of parallel programs. A shared memory model can be provided by hardware, software, or some combination of both. One of the most important problems to be solved in shared memory environments is that of cache coherence. Experience indicates, unsurprisingly, that hardware-coherent multiprocessors greatly outperform distributed shared-memory (DSM) emulations on message-passing hardware. Intermediate options, however, have received considerably less attention. We argue in this position paper that one such option---a multiprocessor or network that provides a global physical address space in which processors can make non-coherent accesses to remote memory without trapping into the kernel or interrupting remote processors---can provide most of the performance of hardware cache coherence at little more monetary or design cost than traditional DSM systems. To support this claim we have developed the Cashmere family of software coherence protocols for NCC-NUMA (Non-Cache-Coherent, Non-Uniform-Memory Access) systems, and have used execution-driven simulation to compare the performance of these protocols to that of full hardware coherence and distributed shared memory emulation. We have found that for a large class of applications the performance of NCC-NUMA multiprocessors rivals that of fully hardware-coherent designs, and significantly surpasses the performance realized on more traditional DSM systems.
Parallel retrograde analysis on a distributed system
Authors: Henri Bal, Victor Allis
Venue: Proceedings of the 1995 ACM/IEEE conference on Supercomputing (CDROM) (1995)

Retrograde Analysis (RA) is an AI search technique used to compute endgame databases, which contain optimal solutions for part of the search space of a game. RA has been applied successfully to several games, but its usefulness is restricted by the huge amount of CPU time and internal memory it requires. We present a parallel distributed algorithm for RA that addresses these problems. RA is hard to parallelize efficiently, because the communication overhead potentially is enormous. We show that the overhead can be reduced drastically using message combining. We implemented the algorithm on an Ethernet-based distributed system. For one example game (awari), we have computed a large database in 50 minutes on 64 processors, whereas one machine took 40 hours (a speedup of 48). An even larger database (computed in 20 hours) would have required over 600 MByte of internal memory on a uniprocessor and would compute for many weeks.
The Convergence of Generalized Lanczos Methods for Large Unsymmetric Eigenproblems
Authors: Zhongxiao Jia
Venue: SIAM Journal on Matrix Analysis and Applications (1995)

In this paper, we investigate the convergence theory of generalized Lanczos methods for solving the eigenproblems of large unsymmetric matrices. Bounds for the distances between normalized eigenvectors and the Krylov subspace ${\cal K}_m(v_1,A)$ spanned by $v_1, Av_1, \ldots, A^{m-1}v_1$ are established, and a priori theoretical error bounds for eigenelements are presented when matrices are defective. Using them we show that the methods will still favor the outer part eigenvalues and the associated eigenvectors of $A$ usually though they may converge quite slowly in the case of $A$ being defective. Meanwhile, we analyze the relationships between the speed of convergence and the spectrum of $A$. However, a detailed analysis exposes that the approximate eigenvectors, Ritz vectors, obtained by generalized Lanczos methods for any unsymmetric matrix cannot be guaranteed to converge in theory even if approximate eigenvalues, Ritz values, do. Therefore, generalized Lanczos algorithms including Arnoldi's algorithm and IOMs with correction are provided with necessary theoretical background.
Learning and extracting initial mealy automata with a modular neural network model
Authors: Peter Tiňo, Jozef Šajda
Venue: Neural Computation (1995)

A hybrid recurrent neural network is shown to learn small initial mealy machines (that can be thought of as translation machines translating input strings to corresponding output strings, as opposed to recognition automata that classify strings as either grammatical or nongrammatical) from positive training samples. A well-trained neural net is then presented once again with the training set and a Kohonen self-organizing map with the "star" topology of neurons is used to quantize recurrent network state space into distinct regions representing corresponding states of a mealy machine being learned. This enables us to extract the learned mealy machine from the trained recurrent network. One neural network (Kohonen self-organizing map) is used to extract meaningful information from another network (recurrent neural network).
Objects to the rescue! or httpd: the next generation operating system
Authors: Andrew P. Black, Jonathan Walpole
Venue: ACM SIGOPS Operating Systems Review (1995)

This position paper suggests that object-oriented operating systems may provide the means to meet the ever-growing demands of applications. As an example of a successful OOOS, we cite the http daemon. To support the contention that httpd is in fact an operating system, we observe that it implements uniform naming, persistent objects and an invocation meta-protocol, specifies and implements some useful objects, and provides a framework for extensibility.We also believe that the modularity that is characteristic of OO systems should provide a performance benefit rather than a penalty. Our ongoing work in the Synthetix project at OGI is exploring the possibilities for advanced optimizations in such systems.
Shape from Contour: Straight Homogeneous Generalized Cylinders and Constant Cross Section Generalized Cylinders
Authors: Faith Ulupinar, Ramakant Nevatia
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1995)

We analyze the properties of Straight Homogeneous Generalized Cylinders (SHGCs) and Constant Cross Section Generalized Cylinders (CGCs), and derive the types of symmetries that the limb boundaries and cross sections of these objects produce on the image plane. The constraints on the 3D shape of the objects are formulated based on the symmetries and from the geometry of the projection models. Finally, the methods that recover the 3D shape from the image of their contours are discussed and recovered surfaces are shown for sample objects.