ppxscal/embedding_network huggingface dataset:
Modular development of interpreters from semantic building blocks
Authors: Jose Emilio Labra Gayo, Juan Manuel Cueva Lovelle, Maria Cándida Luengo Díez, Agustín Cernuda del Río
Venue: Nordic Journal of Computing (2001)

We present an integration of modular monadic semantics and generic programming concepts that facilitates the modular development of interpreters. Using modular monadic semantics, the computational structure is obtained as the composition of several monad transformers where each monad transformer adds a new notion of computation. Using generic programming, it is possible to divide the recursive structure of the abstract syntax in several non-recursive pattern functors. For each functor F, it is possible to define an F-algebra over the computational structure. In this way, an interpreter is automatically obtained as a catamorphism.In this paper we show that it is also possible to use monadic catamorphisms and to combine them with catamorphisms allowing the separation between recursive evaluation from semantic specification. As an example, we define the modular specification of a simple functional programming language with imperative features.
Application of fast spherical Fourier transform to density estimation
Authors: Harrie Hendriks
Venue: Journal of Multivariate Analysis (2003)

This paper is on density estimation on the 2-sphere, S2, using the orthogonal series estimator corresponding to spherical harmonics. In the standard approach of truncating the Fourier series of the empirical density, the Fourier transform is replaced with a version of the discrete fast spherical Fourier transform, as developed by Driscoll and Healy. The fast transform only applies to quantitative data on a regular grid. We will apply a kernel operator to the empirical density, to produce a function whose values at the vertices of such a grid will be the basis for the density estimation. The proposed estimation procedure also contains a deconvolution step, in order to reduce the bias introduced by the initial kernel operator. The main issue is to find necessary conditions on the involved discretization and the bandwidth of the kernel operator, to preserve the rate of convergence that can be achieved by the usual computationally intensive Fourier transform. Density estimation is considered in L2(S2) and more generally in Sobolev spaces Hυ(S2), any υ ≥ 0, with the regularity assumption that the probability density to be estimated belongs to Hs(S2) for some s > υ. The proposed technique to estimate the Fourier transform of an unknown density keeps computing cost down to order O(n), where n denotes the sample size.
Denotative and connotative semantics in hypermedia: proposal for a semiotic-aware architecture
Authors: Frank Nack, Lynda Hardman
Venue: The New Review of Hypermedia and Multimedia (2002)

In this article we claim that the linguistic-centred view within hypermedia systems needs refinement through a semiotic-based approach before real interoperation between media can be achieved. We discuss the problems of visual signification for images and video in dynamic systems, in which users can access visual material in a non-linear fashion. We describe how semiotics can help overcome such problems, by allowing descriptions of the material on both denotative and connotative levels. Finally we propose an architecture for a dynamic semiotic-aware hypermedia system.
A note on the relation between A[a, b] and B[a, b]
Authors: Huan Huang, Jin-xuan Fang
Venue: Fuzzy Sets and Systems (2002)

We point out that the assertion A[a,b] ⊂ B[a,b] of Buckley and Yan (Fuzzy Sets and Systems 115 (2000) 393) is incorrect by a counterexample.
Recursive Update Algorithm for Least Squares Support Vector Machines
Authors: Hoi-Ming Chi, Okan K. Ersoy
Venue: Neural Processing Letters (2003)

In this Letter an efficient recursive update algorithm for least squares support vector machines (LSSVMs) is developed. Using the previous solution and some matrix equations, the algorithm completely avoids training the LSSVM all over again whenever new training sample is available. The gain in speed using the recursive update algorithm is illustrated on four data sets from UCI repository: the Statlog Australian credit, the Pima Indians diabetes, the Wisconsin breast cancer, and the adult income data sets.
A Queueing Theory Model of Nonstationary Traffic Flow
Authors: Dirk Heidemann
Venue: Transportation Science (2001)

The queueing-theoretical model for stationary traffic flow developed in a former paper is extended and modified for nonstationary flow. In particular it is shown how speed-flow-density relationships under nonstationary conditions may deviate from those obtained for stationary conditions. It is shown how the wide scatter which is often observed with empirical speed-flow-density data can be explained by nonstationarity. Furthermore, hysteresis loops, which may show up in speed-flow-density relationships, are interpreted by means of nonstationarity.
Random walks with similar transition probabilities
Authors: Klaus Schiefermayr
Venue: Journal of Computational and Applied Mathematics (2003)

We consider random walks on the nonnegative integers with a possible absorbing state at -1. A random walk is called α-similar to a random walk X if there exist constants Cij such that for the corresponding n-step transition probabilities Pij(n)= α-nCijPij(n), i,j ≥ 0, hold. We give necessary and sufficient conditions for the α-similarity of two random walks both in terms of the parameters and in terms of the corresponding spectral measures which appear in the spectral representation of the n-step transition probabilities developed by Karlin and McGregor.
On algebraic foundations of information granulation
Authors: Helmut Thiele
Venue: Technologies for constructing intelligent systems: Tasks (2002)

In his paper "Towards a theory of fuzzy information granulation and its centrality in human reasoning and fuzzy logic" L.A. ZADEH writes "There are three basic concepts that underline human cognition: granulation, organisation and causation. Informally, granulation involves decomposition of whole into parts; organisation involves integration of parts into whole; and causation involves association of causes with effects.Granulation of an object A leads to a collection of granules of A, with a granule being a clump of points (objects) drawn together by indistinguishability, similarity, proximity or functionality?"Furthermore, he writes: "Modes of information granulation (IG) in which the granules are crisp (c-granular) play important roles in a wide variety of methods, approaches and techniques. Crisp IG, however, does not reflect the fact that in almost all of human reasoning and concept formation the granules are fuzzy (f-granular)."The contribution presented contains first steps to develop a systematic mathematical theory fitting ZADEH's approach. Because of lacking space we restrict our considerations to the generation of granulations by equivalence, tolerance, S4, partial order, and linear order relations, however, in the crisp as well as in the fuzzy case.
Using duality to implicitize and find cusps and inflection points of Bézier curves
Authors: Richard R. Patterson
Venue: Computer Aided Geometric Design (2002)

A planar algebraic curve C has an implicit equation and a tangential equation. The tangential equation defines a dual curve to C. Starting with a parametrization of C, we find a parametrization of the dual curve, and the tangential equation and implicit equation of C in a novel way. We also find equations whose roots are the parameter values of the cusps and inflection points of C. Methods include polar reciprocation and the theory of envelopes.
Automating the Discovery of As-Is Business Process Models: Probabilistic and Algorithmic Approaches
Authors: Kalle Lyytinen, Lars Mathiassen, Janne Ropponen, Anindya Datta
Venue: Information Systems Research (1998)

In the current corporate environment, business organizations have to reengineer their processes to ensure that process performance efficiencies are increased. This goal has lead to a recent surge of work on Business Process Reengineering (BPR) and Workflow Management. While a number of excellent papers have appeared on these topics, all of this work assumes that existing (AS-IS) processes are known. However, as is also widely acknowledged, coming up with AS-IS process models is a nontrivial task, that is currently practiced in a very ad-hoc fashion. With this motivation, in this paper, we postulate a number of algorithms to discover, i.e., come up with models of, AS-IS business processes. Such methods have been implemented as tools which can automatically extr act AS-IS process models. To the best of our knowledge, no such work exists in the BPR and workflow domain. We back up our theoretical work with a case study that illustrates the applicability of these methods to large real-world problems. We draw on previous work on process modeling and grammar discovery. This work is a requisite first step in any reengineering endeavor. Our methods, if adopted, have the potential to severely reduce organizational costs of process redesign.
The effect of numerical diffusion on gas-solids fluidized beds and the use of deferred correction in a finite volume method to stabilize high order discretization of convection terms
Authors: Chris Guenther, Madhava Syamlal
Venue: Scientific computing and applications (2001)

First order methods are commonly used in numerical simulations of gas-solids fluidized beds because they are both stable and affordable. Unfortunately, because of the large amounts of numerical diffusion inherent to these methods higher order methods are recommended to accurately predict bed dynamics e.g., voids or bubbles. The deferred correction method and the downwind factor method are both used for generating linear equations based on a 7-point stencil from higher order discretization formulas. Deferred correction significantly improves the computational speed over the downwind factor method while achieving the same degree of accuracy and under certain conditions allowed computations which the downwind factor method failed.
Portfolio Restructuring and Limits to Hierarchical Governance: the Effects of Environmental Uncertainty and Diversification Strategy
Authors: Donald D. Bergh, Michael W. Lawless
Venue: Organization Science (1998)

The authors test whether acquisitions and divestitures are related to environmental uncertainty and d iversification strategy. Drawing from transaction cost economics, they predicted that increases in environmental uncertainty would reduce a company's ability to manage its subsidiaries efficiently and would lead to divestiture. Conversely, they predicted that decreases in environmental uncertainty would enable a company to manage its subsidiaries more efficiently and would lead to acquisition. Those predictions were expected to be strongest for firms with intermediate levels of diversification, as such firms are believed to be the most difficult to manage efficiently. Repeated measures analyses of a panel of 164 Fortune 500 companies supported the predictions for highly diversified firms (e.g., unrelated businesses) only. Less diversified firms reacted t o increases in uncertainty by acquiring and to decreases in uncertainty by divesting. The results suggest that the relationship between diversification strategy and portfolio restructuring depends on environmental uncertainty. In addition, the study findings imply that there may be limits in the hierarchy's governance efficiency in relation to market modes and that those limits may be affected by environmental uncertainty and diversification strategy.
Stochastic Vehicle Routing Problem with Restocking
Authors: Wen-Huei Yang, Kamlesh Mathur, Ronald H. Ballou
Venue: Transportation Science (2000)

In this paper, a stochastic vehicle routing problem is considered. In particular, customer demand is assumed to be uncertain, and actual demand is revealed only upon the visit to the customer. Instead of adopting the simple recourse action of returning to the depot whenever the vehicle runs out of stock, the points along the route at which restocking is to occur are designed into the route. The restocking points may be before a stockout actually occurs. Two heuristic algorithms are developed to construct both single and multiple routes that minimize total travel cost. The computational results show that the heuristic procedures produce quality solutions and are efficient.
Formal analysis of Suzuki & Kasami distributed mutual exclusion algorithm
Authors: Kazuhiro Ogata, Kokichi Futatsugi
Venue: Proceedings of the IFIP TC6/WG6.1 Fifth International Conference on Formal Methods for Open Object-Based Distributed Systems V (2002)

Since parallel and distributed algorithms are subject to subtle errors that are unlikely to be detected in usual operation, only testing is not enough to reduce errors. Thus, it is necessary to formally analyze such algorithms in order to confirm that they have desirable properties. This paper describes the case study that Suzuki&Kasami distributed mutual exclusion algorithm is formally analyzed. In the case study, the algorithm has been modeled using UNITY-like models called observational transition systems (OTS'S), the model has been described in CafeOBJ, and it has been verified that the algorithm is mutually exclusive and lockout free with the help of CafeOBJ system. In the verification that the algorithm is lockout free, we have found a hidden assumption necessary for the verification, which is not explicitly mentioned in the original paper written by Suzuki and Kasami.
RC 4000 software: multiprogramming system
Authors: Per Brinch Hansen
Venue: The origin of concurrent programming: from semaphores to remote procedure calls (2002)

The RC 4000 multiprogramming system consists of a monitor program that can be extended with a hierarchy of operating systems to suit diverse requirements of program scheduling and resource allocation. This manual defines the functions of the monitor and the basic operating system, which allows users to initiate and control parallel program execution from typewriter consoles. The excerpt reprinted here is the general description of the philosophy and structure of the system. This part will be of interest to anyone wishing an understanding of the system in order to evaluate its possibilities and limitations without going into details about exact conventions. The discussion treats the hardware structure of the RC 4000 only in passing.
Branch-And-Price: Column Generation for Solving Huge Integer Programs
Authors: Cynthia Barnhart, Ellis L. Johnson, George L. Nemhauser, Martin W. P. Savelsbergh, Pamela H. Vance
Venue: Operations Research (1998)

We discuss formulations of integer programs with a huge number of variables and their solution by column generation methods, i.e., implicit pricing of nonbasic variables to generate new columns or to prove LP optimality at a node of the branch-and-bound tree. We present classes of models for which this approach decomposes the problem, provides tighter LP relaxations, and eliminates symmetry. We then discuss computational issues and implementation of column generation, branch-and-bound algorithms, including special branching rules and efficient ways to solve the LP relaxation. We also discuss the relationship with Lagrangian duality.
AwarenessMaps: visualizing awareness in shared workspaces
Authors: Tom Gross, Wido Wirsam, Wolfgang Graether
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

In cooperative activity users require information about their cooperative environment. AwarenessMaps provide the members of shared workspaces with an overview of users and shared documents: the PeopleMap shows an array of pictures of active users fading out over time; and the DocumentMap provides a schematic overview of the structure of a shared workspace and indicates recent changes.
Numerical aspects in developing LP softwares, LPAKO and LPABO
Authors: Woo-Je Kim, Sungmook Lim, Seung-yong Doh, Soondal Park, Jaegeun Ahn
Venue: Journal of Computational and Applied Mathematics (2003)

We have developed two public domain linear programming programs for several years, LPAKO and LPABO, which can solve large-scale sparse LP problems stably and fast. In this paper, several important numerical aspects which were considered in developing LPAKO and LPABO are presented. Common issues are scaling, tolerances and presolving. For the LPAKO, LU factorization and pivoting rule are important aspects. In case of LPABO, Cholesky factorization, ordering and dense column handling are important. In the end of this paper, several issues to be considered in the future development are proposed.
Intrusion-Tolerant Group Management in Enclaves
Authors: Bruno Dutertre, Hassen Saïdi, Victoria Stavridou
Venue: Proceedings of the 2001 International Conference on Dependable Systems and Networks (formerly: FTCS) (2001)

Abstract: Groupware applications require secure communication and group-management services. Participants in such applications may have divergent interests and may not fully trust each other. The services provided must then be designed to tolerate possibly misbehaving participants. Enclaves is a software framework for building such group applications. We discuss how the protocols used by Enclaves can be modified to guarantee proper service in the presence of nontrustworthy group members. We show how the improved protocol was formally specified and proven correct.
The effect of closed labs in computer science I: an assessment
Authors: Amruth N. Kumar
Venue: Journal of Computing Sciences in Colleges (2003)

Retention in our Computer Science I course has been around 50%. In order to improve retention, we started using closed labs in the course. In this paper, we will compare two offerings of our Computer Science I course with not-for-credit closed labs, against two most recent offerings of the course with open labs. We found that closed labs did not help improve retention or project completion rates in the course. However, we observed a qualitative improvement in student learning in the closed lab sections. Our observations suggest that closed labs may be helpful primarily in the first third of the course. We plan to continue to collect and evaluate data to verify these results.
Interval eigenvalue analysis for structures with interval parameters
Authors: Su Huan Chen, Hua Dong Lian, Xiao Wei Yang
Venue: Finite Elements in Analysis and Design (2003)

In this paper, a new method to solve the uncertain eigenvalue problem of structures with interval parameters is presented. The expressions of the interval stiffness matrix and interval mass matrix are developed directly from the interval parameters. With matrix perturbation and interval extension theory, the algorithm for interval eigenvalue analysis is discussed. The computations are based on the element level thus simplifying the calculations greatly, while the sharp bounds are guaranteed by the interval operations. Two numerical examples, a box cantilever beam and an automobile frame both with interval parameters, are given to show the validity of the presented method.
Sales-Force Incentives and Inventory Management
Authors: Fangruo Chen
Venue: Manufacturing Service Operations Management (2000)

This article studies the problem of sales-force compensation by considering the impact of sales-force behavior on a firm's production and inventory system. The sales force's compensation package affects how the salespeople are going to exert their effort, which in turn determines the sales pattern for the firm's product and ultimately drives the performance of the firm's production and inventory system. In general, a smooth demand process facilitates production/inventory planning. Therefore, it is beneficial for a firm to induce its salespeople to exert effort in a way that actually smoothes the demand process. The article proposes a compensation package to induce such behavior. It evaluates and compensates the sales force on a moving-time-window basis, where the length of the time window is determined by the production lead time. Numerical examples show that the proposed package is beneficial to the firm relative to a widely used compensation plan based on annual quotas.
Concretising the programming task: a case study in a secondary school
Authors: Jari M. Lavonen, Veijo P. Meisalo, Matti Lattu, Erkki Sutinen
Venue: Computers Education (2003)

Empirica Control (EC) is a visual programming platform designed primarily for technology education. Students can use EC's visual tools to construct programs for controlling technological processes or systems, as well as to show graphical representation of program functions on a control flow diagram (flowchart). This means that EC is also a useful tool in learning programming. EC unifies flow diagrams with concrete semantics: each program structure corresponds to a factual event in the learner's physical environment, not just as a visual representation on the screen. A teaching experiment for 34 eighth grade (14 years old) students using EC in a learning environment was intended to promote active, co-operative, and problem-centred learning. The data were gathered by teacher interview, observations during a teaching experiment, a questionnaire with a Likert scale instrument, and a test with open tasks. The results indicate that control technology, as implemented in EC, serves as a useful tool for learning principal elements of programming, like control structures, with minimal teaching effort. However, for more complex structures, teacher intervention is clearly required to achieve advanced outcomes. Thus, EC has suggested an important subject for further research: approaching the balance between student-centred exploration and teacher-guided instruction in learning environments.
A note on the hypergraph functor
Authors: Ulrich Höhle
Venue: Fuzzy Sets and Systems (2002)

The purpose of this note is to show that in the case of spatial locales L the hypergraph functor has a right adjoint functor.
Better tiling and array contraction for compiling scientific programs
Authors: Geoff Pike, Paul N. Hilfinger
Venue: Proceedings of the 2002 ACM/IEEE conference on Supercomputing (2002)

Scientific programs often include multiple loops over the same data; interleaving parts of different loops may greatly improve performance. We exploit this in a compiler for Titanium, a dialect of Java. Our compiler combines reordering optimizations such as loop fusion and tiling with storage optimizations such as array contraction (eliminating or reducing the size of temporary arrays).The programmers we have in mind are willing to spend some time tuning their code and their compiler parameters. Given that, and the difficulty in statically selecting parameters such as tile sizes, it makes sense to provide automatic parameter searching alongside the compiler. Our strategy is to optimize aggressively but to expose the compiler's decisions to external control. We double or triple the performance of Gauss-Seidel relaxation and multi-grid (versus an optimizing compiler without tiling and array contraction), and we argue that ours is the best compiler for that kind of program.