ppxscal/embedding_network huggingface dataset:
Randomized Interpolation and Approximationof Sparse Polynomials
Authors: Yishay Mansour
Venue: SIAM Journal on Computing (1995)

We present a randomized algorithm that interpolates a sparse polynomial in polynomial time in the bit complexity model. The algorithm can be also applied to approximate polynomials that can be approximated by sparse polynomials (the approximation is in the $L_2$ norm).
Parallelization of a three-dimensional shallow-water estuary model on the KSR-1
Authors: C. Falcó Korn, J. M. Bull, G. D. Riley, P. K. Stansby
Venue: Scientific Programming (1995)

Flows in estuarial and coastal regions may be described by the shallow-water equations. The processes of pollution transport, sediment transport, and plume dispersion are driven by the underlying hydrodynamics. Accurate resolution of these processes requires a three-dimensional formulation with turbulence modeling, which is very demanding computationally. A numerical scheme has been developed which is both stable and accurate - we show that this scheme is also well suited to parallel processing, making the solution of massive complex problems a practical computing possibility. We describe the implementation of the numerical scheme on a Kendall Square Research KSR-1 multiprocessor, and present experimental results which demonstrate that a problem requiring 600,000 mesh points and 6,000 time steps can be solved in under 8 hours using 32 processors.
On the Relationship Between Partition and Random Testing
Authors: T. Y. Chen, Y. T. Yu
Venue: IEEE Transactions on Software Engineering (1994)

Weyuker and Jeng have investigated the conditions that affect the performance of partition testing and have compared analytically the fault-detecting ability of partition testing and random testing. This paper extends and generalizes some of their results. We give more general ways of characterizing the worst case for partition testing, along with a precise characterization of when this worst case is as good as random testing. We also find that partition testing is guaranteed to perform at least as well as random testing so long as the number of test cases selected is in proportion to the size of the subdomains.
On adaptive diagnostic test generation
Authors: Yiming Gong, Sreejit Chakravarty
Venue: Proceedings of the 1995 IEEE/ACM international conference on Computer-aided design (1995)

Adaptive Diagnosis, a paradigm for diagnosis, is defined. A system based on this paradigm, for I_{DDQ} measurement based diagnosis of bridging faults, is reported. Experimental evaluation of the system shows it to be substantially superior to existing systems, especially for larger circuits.
Algorithm 746: PCOMP&mdash;a Fortran code for automatic differentiation
Authors: M. Dobmann, M. Liepelt, K. Schittkowski
Venue: ACM Transactions on Mathematical Software (TOMS) (1995)

Automatic differentiation is an interesting and important tool for all numerical algorithms that require derivatives, e.g., in nonlinear programming, optimal control, parameter estimation, and differential equations. The basic idea is to avoid not only numerical approximations, which are expensive with respect to CPU time and contain round-off errors, but also hand-coded differentiation. This article introduces the forward and backward accumulation methods and describes the numerical implementation of a computer code with the name PCOMP. The main intention of the approach used is to provide a flexible and portable Fortran code for practical applications. The underlying language is described in terms of a formal grammar and is a subset of Fortran with a few extensions. Besides a parser that generates an intermediate code and that can be executed independently from the evaluation routines, there are other subroutines for the direct computation of function and gradient values, which can be called directly from a user program. On the other hand, it is possible to generate a Fortran code for function and gradient evaluation that can be compiled and linked separately.
Relationships between selected organizational factors and systems development
Authors: Ananth Srinivasan, Kate M. Kaiser
Venue: Communications of the ACM (1987)

Three organizational variables influence the quality of the system development process: available resources (both human and financial), external influences on the development process, and the project team's exposure to information systems. Public information and interviews with systems managers from 28 large private firms yielded data about the organizational variables. Systems project group members completed questionnaires concerning the system development process. The results indicate that human resources affect the development process positively, but increased financial resources are related to team disagreement. The degree of external influence on the system development effort needs to be carefully monitored and controlled. Systems exposure in the firm allows an increase in the degree of awareness among project group members about the different problems encountered by users and systems staff.
Participatory analysis of flexibility
Authors: Arne Kjær, Kim Halskov Madsen
Venue: Communications of the ACM (1995)

Analysis as part of requirements gathering, conducted according to conventional systems development approaches like structured analysis and object-oriented analysis, focuses on standard data formats and general data flow. The data dictionaries and data flow diagrams of Yourdon's structured project life-cycle [21] model the general standard data format and flow, respectively. Within the object-oriented paradigm Booch [2] emphasizes, quoting W. Wulf, that: We (humans) have developed an exceptionally powerful technique for dealing with complexity. We abstract from it. Unable to master the entirely of an object, we choose to ignore its essential details, dealing with the generalized, idealized model of the object. (Our emphasis).
Theory and application of Marsaglia's monkey test for pseudorandom number generators
Authors: Ora E. Percus, Paula A. Whitlock
Venue: ACM Transactions on Modeling and Computer Simulation (TOMACS) (1995)

A theoretical analysis is given for a new test, the &ldquo;Monkey&rdquo; test, for pseudorandom number sequences, which was proposed by Marsaglia. Selected results, using the test on several pseudorandom number generators in the literature, are also presented.
The evolution of MaxSix trusted networking
Authors: John R. Adams, David F. Luther
Venue: ACM SIGSAC Review (1995)

Through TSIG (the Trusted Systems Interoperability Group) and Project Max, trusted systems vendors have been working together for several years to achieve Multi-level Secure (MLS) system interoperability. As a standards body, TSIG has focused on specifications, while the Project Max group has focused on producing an implementation known as MaxSix. SecureWare, as the founder of TSIG and Project Max, has been a key contributor to the TSIG specifications and the development of MaxSix.
On the Complexity of Function Learning
Authors: Peter Auer, Philip M. Long, Wolfgang Maass, Gerhard J. Woeginger
Venue: Machine Learning (1995)

The majority of results in computational learning theory are concerned with concept learning, i.e. with the special case of function learning for classes of functions with range &lcub;0, 1&rcub;. Much less is known about the theory of learning functions with a larger range such as {\Bbb N} or {\Bbb R}. In particular relatively few results exist about the general structure of common models for function learning, and there are only very few nontrivial function classes for which positive learning results have been exhibited in any of these models.We introduce in this paper the notion of a binary branching adversary tree for function learning, which allows us to give a somewhat surprising equivalent characterization of the optimal learning cost for learning a class of real-valued functions (in terms of a max-min definition which does not involve any &ldquo;learning&rdquo; model).Another general structural result of this paper relates the cost for learning a union of function classes to the learning costs for the individual function classes.Furthermore, we exhibit an efficient learning algorithm for learning convex piecewise linear functions from {\Bbb R}^d into {\Bbb R}. Previously, the class of linear functions from {\Bbb R}^d into {\Bbb R} was the only class of functions with multidimensional domain that was known to be learnable within the rigorous framework of a formal model for online learning.Finally we give a sufficient condition for an arbitrary class {\cal F} of functions from {\Bbb R} into {\Bbb R} that allows us to learn the class of all functions that can be written as the pointwise maximum of k functions from {\cal F}. This allows us to exhibit a number of further nontrivial classes of functions from {\Bbb R} into {\Bbb R} for which there exist efficient learning algorithms.
HODFA: an architectural framework for homogenizing heterogeneous legacy databases
Authors: Kamalakar Karlapalem, Qing Li, Chung-Dak Shum
Venue: ACM SIGMOD Record (1995)

One of the main difficulties in supporting global applications over a number of localized databases and migrating legacy information systems to modern computing environment is to cope with the heterogeneities of these systems. In this paper, we present a novel flexible architecture (called HODFA) to dynamically connect such localized heterogeneous databases in forming a homogenized federated database system and to support the process of transforming a collection of heterogeneous information systems onto a homogeneous environment. We further develop an incremental methodology of homogenization in the context of our HODFA framework, which can facilitate different degrees of homogenization in a stepwise manner, so that existing applications will not be affected during the process of homogenization.
First-class synchronization barriers
Authors: Franklyn Turbak
Venue: ACM SIGPLAN Notices (1996)

Our purpose is to promote a second-class mechanism --- the synchronization barrier --- to a first-class value. We introduce the synchron, a novel synchronization mechanism that enables the coordination of a dynamically varying set of concurrent threads that share access to a first-class synchronization token. We demonstrate how synchrons can be used to modularly manage resources in cases where existing techniques are either inapplicable or non-modular. In particular, synchronized lazy aggregates enable the first space-efficient aggregate data decomposition of a wide range of algorithms. We also introduce explicit-demand graph reduction, a new semantic framework that we have developed to describe concurrency and explain the meaning of a synchron rendezvous.
Modelling the business process to derive organisational requirements for information technology
Authors: Andrew Blyth
Venue: ACM SIGOIS Bulletin (1995)

Organisations today perceive information technology systems as vital to their success. The effective application of information from an organisational perspective can mean the difference between success or failure. The ORDIT (organisational requirements definition for information technology) approach was developed as a socio-technical systems based methodology, its purpose is to facilitate problem solvers and problem owners in developing the correct understanding of what is required, why it is required and when it is required, of the system. Within this paper we will present a case study in which the ORDIT methodology is applied to an information technology system for an accident and emergency department of an inner city hospital for the purpose of eliciting, representing and validating organisational requirements for information technology. The hospital recognizes that the introduction of an information system is vital and that its specification is fraught with danger. It was against this backdrop that the case study was performed.
Uniform Stabilization of a Hybrid System of Elasticity
Authors: Bopeng Rao
Venue: SIAM Journal on Control and Optimization (1995)

The problem of boundary feedback stabilization of a Euler-Bernoulli beam with an endmass is considered. Using a method of compact perturbation, the lack of uniform stabilization is proved in the case of a clamped beam with the usual boundary feedbacks applied to the end with the mass. Next, the uniform stabilization when the usual boundary feedbacks are applied to the end without the mass is proved. Also the uniform decay of energy by means of higher-order feedbacks applied to the end with the mass is established.
Group Weighted Matchings in Bipartite Graphs
Authors: R. Aharoni, R. Meshulam, B. Wajnryb
Venue: Journal of Algebraic Combinatorics: An International Journal (1995)

Let G be a bipartite graph with bicoloration &lcub;A, B&rcub;, &verbar;A&verbar; &equals; &verbar;B&verbar;, and let w : E(G) &rarr; K where K is a finite abelian group with k elements. For a subset S &sub; E(G) let w(S)=\prod _{e \in S} w(e). A Perfect matching M &sub; E(G) is a w-matching if w(M) &equals; 1.A characterization is given for all w's for which every perfect matching is a w-matching.It is shown that if G &equals; Kk+1,k+1 then either G has no w-matchings or it has at least 2 w-matchings.If K is the group of order 2 and deg(a) &ge; d for all a &isin; A, then either G has no w-matchings, or G has at least (d &minus; 1)&excl; w-matchings.
Query caching and optimization in distributed mediator systems
Authors: S. Adali, K. S. Candan, Y. Papakonstantinou, V. S. Subrahmanian
Venue: ACM SIGMOD Record (1996)

Query processing and optimization in mediator systems that access distributed non-proprietary sources pose many novel problems. Cost-based query optimization is hard because the mediator does not have access to source statistics information and furthermore it may not be easy to model the source's performance. At the same time, querying remote sources may be very expensive because of high connection overhead, long computation time, financial charges, and temporary unavailability. We propose a cost-based optimization technique that caches statistics of actual calls to the sources and consequently estimates the cost of the possible execution plans based on the statistics cache. We investigate issues pertaining to the design of the statistics cache and experimentally analyze various tradeoffs. We also present a query result caching mechanism that allows us to effectively use results of prior queries when the source is not readily available. We employ the novel invariants mechanism, which shows how semantic information about data sources may be used to discover cached query results of interest.
Safe: a semantic technique for transforming programs in the presence of errors
Authors: Alexander Aiken, John H. Williams, Edward L. Wimmers
Venue: ACM Transactions on Programming Languages and Systems (TOPLAS) (1995)

Language designers and implementors have avoided specifying and preserving the meaning of programs that produce errors. This is apparently because being forced to preserve error behavior limits severely the scope of program optimization, even for correct programs. However, error behavior preservation is desirable for debugging, and error behavior must be preserved in any language that permits user-generated errors (i.e., exceptions).This article presents a technique for expressing general program transformations for languages that possess a rich collection of distinguishable error values. This is accomplished by defining a higher-order function called Safe, which can be used to annotate those portions of a program that are guaranteed not to produce errors. It is shown that this facilitates the expression of very general program transformations, effectively giving program transformations in a language with many error values the same power and generality as program transformations in a language with only a single error value.Using the semantic properties of Safe, it is possible to provide some useful sufficient conditions for establishing the correctness of transformations in the presence of errors. In particular, a Substitutability theorem is proven, which can be used to justify &ldquo;in-context&rdquo; optimizations: transformations that alter the meanings of subexpressions without changing the meaning of the whole program. Finally, the effectiveness of the technique is demonstrated by some examples of its use in an optimizing compiler.
Global Virtual Time and distributed synchronization
Authors: Jeffrey S. Steinman, Craig A. Lee, Linda F. Wilson, David M. Nicol
Venue: ACM SIGSIM Simulation Digest (1995)

Global Virtual Time (GVT) is the fundamental synchronization concept in optimistic simulations. It is defined as the earliest time tag within the set of unprocessed pending events in distributed simulation. A number of techniques for determining GVT have been proposed in recent years, each having their own intrinsic properties. However, most of these techniques either focus on specific types of simulation problems or assume specific hardware support. This paper specifically addresses the GVT problem in the context of the following area&bull; Scalability&bull; Efficiency&bull; Portability&bull; Flow control&bull; Interactive support&bull;Real time useA new GVT algorithm, called SPEEDES GVT, has been developed in the Synchronous Parallel Environment for Emulation and Discrete-Event Simulation (SPEEDES) framework. The new algorithm runs periodically but does not disrupt event processing. It provides flow control by processing events risk-free while flushing out messages during the GVT computation. SPEEDES GVT is built from a set of global reduction operations that are easily implementable on any hardware system.
A Parallel Computing Approach to Creating Engineering Concept Spaces for Semantic Retrieval: The Illinois Digital Library Initiative Project
Authors: Hsinchun Chen, Bruce Schatz, Tobun Ng, Joanne Martinez, Amy Kirchhoff, Chienting Lin
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1996)

This research presents preliminary results generated from the semantic retrieval research component of the Illinois Digital Library Initiative (DLI) project. Using a variation of the automatic thesaurus generation techniques, to which we refer as the concept space approach, we aimed to create graphs of domain-specific concepts (terms) and their weighted co-occurrence relationships for all major engineering domains. Merging these concept spaces and providing traversal paths across different concept spaces could potentially help alleviate the vocabulary (difference) problem evident in large-scale information retrieval. We have experimented previously with such a technique for a smaller molecular biology domain (Worm Community System, with 10+ MBs of document collection) with encouraging results.In order to address the scalability issue related to large-scale information retrieval and analysis for the current Illinois DLI project, we recently conducted experiments using the concept space approach on parallel supercomputers. Our test collection included 2+ GBs of computer science and electrical engineering abstracts extracted from the INSPEC database. The concept space approach called for extensive textual and statistical analysis (a form of knowledge discovery) based on automatic indexing and co-occurrence analysis algorithms, both previously tested in the biology domain. Initial testing results using a 512-node CM-5 and a 16-processor SGI Power Challenge were promising. Power Challenge was later selected to create a comprehensive computer engineering concept space of about 270,000 terms and 4,000,000+ links using 24.5 hours of CPU time. Our system evaluation involving 12 knowledgeable subjects revealed that the automatically-created computer engineering concept space generated significantly higher concept recall than the human-generated INSPEC computer engineering thesaurus. However, the INSPEC was more precise than the automatic concept space. Our current work mainly involves creating concept spaces for other major engineering domains and developing robust graph matching and traversal algorithms for cross-domain, concept-based retrieval. Future work also will include generating individualized concept spaces for assisting user-specific concept-based information retrieval.
New Techniques for Exact and Approximate Dynamic Closest-point
Authors: Sanjiv Kapoor, Michiel Smid
Venue: SIAM Journal on Computing (1996)

Let $S$ be a set of $n$ points in $\IR^{D}$. It is shown that a range tree can be used to find an $L_{\infty}$-nearest neighbor in $S$ of any query point, in $O((\log n)^{D-1} \log\log n)$ time. This data structure has size $O(n (\log n)^{D-1})$ and an amortized update time of $O((\log n)^{D-1} \log\log n)$. This result is used to solve the $(1+\epsilon)$-approximate $L_{2}$-nearest neighbor problem within the same bounds (up to a constant factor that depends on $\epsilon$ and $D$). In this o problem, for any query point $p$, a point $q \in S$ is computed such that the euclidean distance between $p$ and $q$ is at most $(1+\epsilon)$ times the euclidean distance between $p$ and its true nearest neighbor. This is the first dynamic data structure for this problem having close to linear size and polylogarithmic query and update times. New dynamic data structures are given that maintain a closest pair of $S$. For $D \geq 3$, a structure of size $O(n)$ is presented with amortized update time $O((\log n)^{D-1} \log\log n)$. The constant factor in this space (resp.\ time bound) is of the form $O(D)^D$ (resp.\ $2^{O(D^2)}$). For $D=2$ and any non-negative integer constant $k$, structures of size $O(n \log n / (\log\log n)^{k})$ (resp.\ $O(n)$) are presented having an amortized update time of $O(\log n \log\log n)$ (resp.\ $O((\log n)^{2} / (\log\log n)^{k})$). Previously, no deterministic linear size data structure having polylogarithmic update time was known for this problem.
Deterministic part-of-speech tagging with finite-state transducers
Authors: Emmanuel Roche, Yves Schabes
Venue: Computational Linguistics (1995)

Stochastic approaches to natural language processing have often been preferred to rule-based approaches because of their robustness and their automatic training capabilities. This was the case for part-of-speech tagging until Brill showed how state-of-the-art part-of-speech tagging can be achieved with a rule-based tagger by inferring rules from a training corpus. However, current implementations of the rule-based tagger run more slowly than previous approaches. In this paper, we present a finite-state tagger, inspired by the rule-based tagger, that operates in optimal time in the sense that the time to assign tags to a sentence corresponds to the time required to follow a single path in a deterministic finite-state machine. This result is achieved by encoding the application of the rules found in the tagger as a nondeterministic finite-state transducer and then turning it into a deterministic transducer. The resulting deterministic transducer yields a part-of-speech tagger whose speed is dominated by the access time of mass storage devices. We then generalize the techniques to the class of transformation-based systems.
A field-programmable mixed-analog-digital array
Authors: Paul Chow, P. Glenn Gulak
Venue: Proceedings of the 1995 ACM third international symposium on Field-programmable gate arrays (1995)

A novel field-programmable mixed-analog-digital array (FPMA) is proposed, which contains a field-programmable analog array, a field-programmable digital array, and a mixed-signal interface. This device is intended to be used for the rapid implementation of mixed-signal circuits. The resource and architectural requirements for this array are determined by analyzing a set of sample circuits. The mixed-signal interface is constructed from converter blocks that contain configurable A/D and D/A converters, which gives some flexibility in the specification of the interface. A 1.2 &mgr;m CMOS prototype IC has been designed to demonstrate the feasibility of FPMA technology.