ppxscal/embedding_network huggingface dataset:
Computing Laplace Transforms for Numerical Inversion Via Continued Fractions
Authors: Joseph Abate, Ward Whitt
Venue: INFORMS Journal on Computing (1999)

It is often possible to effectively calculate probability density functions (pdf's) and cumulative distribution functions (cdf's) by numerically inverting Laplace transforms. However, to do so it is necessary to compute the Laplace transform values. Unfortunately, convenient explicit expressions for required transforms are often unavailable for component pdf's in a probability model. In that event, we show that it is sometimes possible to find continued-fraction representations for required Laplace transforms that can serve as a basis for computing the transform values needed in the inversion algorithm. This property is very likely to prevail for completely monotone pdf's, because their Laplace transforms have special continued fractions called S fractions, which have desirable convergence properties. We illustrate the approach by considering applications to compute first-passage-time cdfs in birth-and-death processes and various cdf's with non-exponential tails, which can be used to model service-time cdf's in queueing models. Included among these cdf's is the Pareto cdf.
Encoding linear logic with interaction combinators
Authors: Ian Mackie, Jorge Sousa Pinto
Venue: Information and Computation (2002)

The purpose of this paper is to demonstrate how Lafont's interaction combinators, a system of three symbols and six interaction rules, can be used to encode linear logic. Specifically, we give a translation of the multiplicative, exponential, and additive fragments of linear logic together with a strategy for cut-elimination which can be faithfully simulated. Finally, we show briefly how this encoding can be used for evaluating λ-terms. In addition to offering a very simple, perhaps the simplest, system of rewriting for linear logic and the λ-calculus, the interaction net implementation that we present has been shown by experimental testing to offer a good level of sharing in terms of the number of cut-elimination steps (resp. β-reduction steps). In particular it performs better than all extant finite systems of interaction nets.
Distributed multiprocessor environments
Authors: Timothy Rolfe
Venue: Journal of Computing Sciences in Colleges (2002)

This paper discusses the material included in a seminar for seniors and graduate students on distributed parallel processing offered as an experimental course at Eastern Washington University in the Fall 2000 and Winter 2002 quarters, along with the difficulties discovered as the courses progressed.
Adaptive Labeling Algorithms for the Dynamic Assignment Problem
Authors: Warren B. Powell, Wayne Snow, Raymond K. Cheung
Venue: Transportation Science (2000)

We consider the problem of dynamically routing a driver to cover a sequence of tasks (with no consolidation), using a complex set of driver attributes and operational rules. Our motivating application is dynamic routing and scheduling problems, which require fast response times, the ability to handle a wide range of operational concerns, and the ability to output multiple recommendations for a particular driver. A mathematical formulation is introduced that easily handles real-world operational complexities. Two new optimization-based heuristics are described, one giving faster performance and the second providing somewhat higher solution quality. Comparisons to optimal solutions are provided, which measure the quality of the solutions that our algorithms provide. Experimental tests show that our algorithms provide high quality solutions, and are fast enough to be run in real-time applications.
Approximate Bayesian networks
Authors: Dominik Ślȩzak
Venue: Technologies for constructing intelligent systems: tools (2002)

We introduce the notion of an approximate Bayesian network, which almost keeps the information entropy of data and encodes knowledge about approximate dependencies between features. Presented theoretical results, as well as relationships to fundamental concepts of the rough set theory, provide a novel methodology of applying the Bayesian net models to the real life data analysis.
Applications of q-Taylor theorems
Authors: Mourad E. H. Ismail, Dennis Stanton
Venue: Journal of Computational and Applied Mathematics (2003)

We establish two new q-analogues of a Taylor series expansion for polynomials using special Askey-Wilson polynomial bases. Combining these expansions with an earlier expansion theorem we derive inverse relations and evaluate certain linearization coefficients. Byproducts include new summation theorems, new results on a q-exponential function, and quadratic transformations for q-series.
On the evolution of PON-based FTTH solutions
Authors: Kyeong Soo Kim
Venue: Information Sciences&mdash;Informatics and Computer Science: An International Journal (2003)

Passive Optical Network (PON)-based Fiber-To-The-Home (FTTH) is a promising solution that can break through the economic barrier of traditional point-to-point solutions. Once fibers are deployed with PON-based FTTH solutions, it becomes critical how to migrate to Wavelength Division Multiplexing (WDM)-PON because Time Division Multiplexing (TDM) used in current PON solutions cannot exploit the huge bandwidth of the optical fibers and therefore will not be able to meet ever-increasing demands for higher bandwidth by future network applications. In this paper we review and compare the current PON-based FTTH solutions, ATM-PON (APON) and Ethernet PON (EPON), and provide a possible evolution scenario to future WDMPON.
On the Design Problem of Multitechnology Networks
Authors: Steven Chamberland, Brunilde Sansò
Venue: INFORMS Journal on Computing (2001)

In this article we propose a model for the topological design problem of multitechnology networks that includes the location of switches and their port configuration, the design of an access network (with single and double access links) and a backbone network. The model specifically takes into account different types of modular switches where each type is characterized by its cost, its capacity in terms of the number of slots, and by its switch fabric capacity. The mutitechnology qualifier stems from the fact that several technologies and rates can be used in the access network. The proposed model is of the integer-programming variety, and in order to find a good solution, we propose a starting heuristic that provides an initial solution and the tabu-search algorithm to improve the solution. Lower bounds are proposed and used to assess the performance of the tabu-based approach. Numerical results for randomly generated problems with up to 500 clients and 50 potential switch sites are presented. The tabu-search algorithm produced solutions that were, on average, within 2.11% of the best lower bound.
A lost cause: the ever-improving developer's map
Authors: Mette Kjaersgaard, Jesper Pedersen, Tom Djajadiningrat
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

In this paper we describe our work in the Danfoss User Centred Design Group on the design for a frequency converter, a device which controls the speed of an electric motor. A significant part of this project lies in getting to know often unfamiliar users and use contexts. We feel that developers often look at the user's problems through developers eyes rather than through the user's eyes. Having researched and actively used ethnographic field methods over the past few years, we argue that it is necessary to create an awareness of this perspective issue, its consequences for how we interpret field sessions and its influence on product development. We present a collection of existing methods that can be applied to challenge our perspective as developers and to shift our view to that of the users. To illustrate how these methods may lead to a deeper understanding we start with a portrait of one of our informants. We present two provotypes to show how we try to incorporate the users' perspective in our design solutions. Finally, we reflect on the interaction language which products speak and argue that usability studies without awareness of the perspective issue make products more clear for the developers only.
Optimizing Inventory Replenishment of Retail Fashion Products
Authors: Marshall Fisher, Kumar Rajaram, Ananth Raman
Venue: Manufacturing Service Operations Management (2001)

We consider the problem of determining (for a short lifecycle) retail product initial and replenishment order quantities that minimize the cost of lost sales, back orders, and obsolete inventory. We model this problem as a two-stage stochastic dynamic program, propose a heuristic, establish conditions under which the heuristic finds an optimal solution, and report results of the application of our procedure at a catalog retailer. Our procedure improves on the existing method by enough to double profits. In addition, our method can be used to choose the optimal reorder time, to quantify the benefit of leadtime reduction, and to choose the best replenishment contract.
Assembly-Line Scheduling with Concurrent Operations and Parallel Machines
Authors: George J. Kyparisis, Christos Koulamas
Venue: INFORMS Journal on Computing (2002)

This paper addresses the assembly-line scheduling problem with concurrent operations per stage and parallel machines. This problem can be briefly described as the problem of sequencing a predetermined set of parts with known processing-time requirements through anr-station assembly line so that the makespan is minimized. A set of concurrent operations must be performed at each station on each part. This set of operations is usually partdependent since different parts have different processing requirements. In this paper, we construct schedules in quadratic time for this strongly NP-hard problem with an absolute performance guarantee independent of the number of jobs. This makes our schedules asymptotically optimal as the number of jobs becomes very large. The implementation of our schedules facilitates the efficient use of concurrent operations and prevents the assembly line from degenerating into performing operations serially, which would result in low production rates. We utilize compact vector summation techniques and first construct a schedule for the case where each concurrent operation is performed by a single machine. We then generalize our schedule to the case where each concurrent operation is performed by a set of identical parallel machines.
Decision Making Under Uncertainty: Is Sensitivity Analysis of Any Use?
Authors: Stein W. Wallace
Venue: Operations Research (2000)

Sensitivity analysis, combined with parametric optimization, is often presented as a way of checking if the solution of a deterministic linear program is reliable--even if some of the parameters are not fully known but are instead replaced by a best guess, often a sample mean. It is customary to claim that if the region over which a certain basis is optimal is large, one is fairly safe by using the solution of the linear program. If not, the parametric analysis will provide us with alternative solutions that can be tested. This way, sensitivity analysis is used to facilitate decision making under uncertainty by means of a deterministic tool, namely parametric linear programming. We show in this note that this basic idea of stability has little do with optimality of an optimization problem where the parameters are uncertain.
Rough isometry and energy finite solutions of the Schrödinger operator on graphs
Authors: Yong Hah Lee
Venue: Discrete Mathematics (2003)

We prove that the dimension of the space of energy finite bounded solutions of the Schrödinger operator is invariant under rough isometries between graphs of bounded degree. This result generalizes those of Soardi and of the present author.
Agency and Institutions: National Divergences in Diversification Behavior
Authors: Bruce Kogut, Gordon Walker, Jaideep Anand
Venue: Organization Science (2002)

A fundamental theme in comparative crosscountry research is the convergence of organizational forms in diverse national settings. In this paper we examine a special instance of this theme: the pattern of diversification across industries. A common argument is that technical and market forces compel firms to adopt ?coherent? strategies of diversification. This thesis implies that there should be a convergence in the patterns of interindustry diversification in all market-based economies. An institutional approach offers an alternative view. From this perspective, when diversification across industries is seen as subject to nation-specific governance and resource constraints, countries should vary widely in their interindustry diversification patterns.To test these alternative views, we analyze the diversification patterns of large corporations from five countries: France, Germany, Japan, the United Kingdom, and the United States. Our results do not support the hypothesis of a common pattern of diversification across countries, and thus reject the technological thesis. By comparing two case studies in which entrepreneurs attempted to diversify by acquisition in France and the United States, we examine how institutions and agents interact to permit different diversification patterns to arise in diverse national environments.The statistical results and case studies imply that, given the fixity of certain institutions, even if countries are subject to globalization, convergence in diversification patterns is not necessary. The results cast doubt upon the merits of stylizing the debate as a choice between technical and institutional theories of organizational choice. Rather, the study points to the importance of two theoretical statements. The first is to inquire under what conditions there is likely to be consensus on a given ?means-end? rationality for a specific managerial decision (e.g., diversification). The second is to understand the structural opportunities available to entrepreneurs for diversifying through acquisitions. Iterating between these cognitive and structural considerations shifts the focus from the false debate between technological and institutional arguments to the study of entrepreneurship situated in historically given national environments.
Explicit and Implicit Structuring of Genres in Electronic Communication: Reinforcement and Change of Social Interaction
Authors: Joanne Yates, Wanda J. Orlikowski, Kazuo Okamura
Venue: Organization Science (1999)

In a study of how an R&D group in a Japanese firm adopted and used a new electronic medium, we identified two contrasting patterns of use: the use of community-wide communication types, or genres, deliberately shaped by the action of a small, sanctioned group of mediators; and the use of local genres tacitly shaped by members within their own research teams. We suggest that these patterns reflect the more general processes of explicit and implicit structuring, resulting in both the reinforcement and change of social interaction within communities. Explicit st ructuring included the planned replication, planned modification, and opportunistic modification of existing genres, while implicit structuring included the migration and variation of existing genres. We believe that these two processes provide suggestive models for understanding the initial and ongoing use of new electronic media within a community.
Yamamoto's principle and its applications to precise finite element error analysis
Authors: Takuya Tsuchiya, Kazuki Yoshida, Sae Ishioka
Venue: Journal of Computational and Applied Mathematics (2003)

Suppose that we discretize an elliptic boundary value problem and obtain a linear equation Ax = f. In many case, the inverse matrix A-1 is closely related to the Green function of the original boundary value problem. This fact is called Yamamoto's principle. In this paper, using Yamamoto's principle, we develop a precise error analysis of the piecewise linear finite element method for two-point boundary value problems with discontinuous and not necessarily positive coefficient functions. We show that precise error estimations, similar to known error bounds, are obtained even in this case.
A branch and bound algorithm to minimize the total weighted flowtime for the two-stage assembly scheduling problem
Authors: Ali Tozkapan, Ömer Kirca, Chia-Shin Chung
Venue: Computers and Operations Research (2003)

In this paper, a two-stage assembly scheduling problem is considered with the objective of minimizing the total weighted flowtime. A lower bounding procedure and a dominance criterion are developed and incorporated into a branch and bound procedure. A heuristic procedure is also used to derive an initial upper bound. Computational results of the algorithm are presented.
An analytical solution of the S-model kinetic equations
Authors: D. Valougeorgis
Venue: Zeitschrift f&uuml;r Angewandte Mathematik und Physik (ZAMP) (2003)

An analytical variation of the discrete ordinates method is used to establish a concise and accurate solution to the plane Poiseuille and thermal creep problems based on the S-model kinetic equations. The results are of high accuracy and include the flow rates and the heat fluxes of both problems for a wide range of Knudsen numbers and various values of the accommodation coefficient at the boundaries.
Advanced memory allocation
Authors: Gianluca Insolvibile
Venue: Linux Journal (2003)

Keeping memory requirements low cansave you time and money. Here's how to bend malloc() to your will.
Anycasting-based protocol for geocast service in mobile ad hoc networks
Authors: Young-Bae Ko, Nitin H. Vaidya
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2003)

Geocasting is a variation on the notion of multicasting. Geocasting is useful for sending messages to nodes in a specified geographical region. This region is called the geocast region. This paper presents a protocol, named Geo-TORA , for geocasting in mobile ad hoc networks. The proposed GeoTORA protocol combines anycasting with local flooding to implement geocasting. Thus, GeoTORA requires two phases for geocasting. First, it performs anycasting from a source to any node in the geocast region, by modifying the Temporally-Ordered Routing Algorithm (TORA) (unicast) routing protocol. Subsequently, localized flooding within the geocast region is performed to deliver the messages to nodes within the geocast region. This integration of TORA and local flooding can significantly reduce the overhead of geocast delivery, while maintaining reasonably high accuracy.
Least Expected Time Paths in Stochastic, Time-Varying Transportation Networks
Authors: Elise D. Miller-Hooks, Hani S. Mahmassani
Venue: Transportation Science (2000)

We consider stochastic, time-varying transportation networks, where the arc weights (arc travel times) are random variables with probability distribution functions that vary with time. Efficient procedures are widely available for determining least time paths in deterministic networks. In stochastic but time-invariant networks, least expected time paths can be determined by setting each random arc weight to its expected value and solving an equivalent deterministic problem. This paper addresses the problem of determining least expected time paths in stochastic, time-varying networks. Two procedures are presented. The first procedure determines the a priori least expected time paths from all origins to a single destination for each departure time in the peak period. The second procedure determines lower bounds on the expected times of these a priori least expected time paths. This procedure determines an exact solution for the problem where the driver is permitted to react to revealed travel times on traveled links en route, i.e., in a time-adaptive route choice framework. Modifications to each of these procedures for determining least expected cost (where cost is not necessarily travel time) paths and lower bounds on the expected costs of these paths are given. Extensive numerical tests are conducted to illustrate the algorithms' computational performance as well as the properties of the solution.
Minmax Regret Median Location on a Network Under Uncertainty
Authors: Igor Averbakh, Oded Berman
Venue: INFORMS Journal on Computing (2000)

We consider the 1-median problem on a network with uncertain weights of nodes. Specifically, for each node, only an interval estimate of its weight is known. It is required to find the "minimax regret" location, i.e., to minimize the worst-case loss in the objective function that may occur because a decision is made without knowing which state of nature will take place. We present the first polynomial algorithm for this problem on a general network. For the problem on a tree network, we discuss an algorithm with an order of complexity improved over the algorithms known in the literature.
PET, a software monitoring toolkit for performance analysis of parallel embedded applications
Authors: J. García, J. Entrialgo, D. F. García, J. L. Díaz, F. J. Suárez
Venue: Journal of Systems Architecture: the EUROMICRO Journal (2003)

Since the late 1980s a great deal of research has been dedicated to the development of software monitoring and visualization toolkits for parallel systems. These toolkits have traditionally been oriented to measuring and analyzing parallel scientific applications. However, nowadays, other types of parallel applications, using signal-processing or image-processing techniques, are becoming increasingly importance in the field of embedded computing. Such applications are executed on special parallel computers, normally known as embedded multiprocessors, and they exhibit structural and behavioral characteristics very different from scientific applications. Because of this, monitoring tools with specific characteristics are required for measuring and analyzing parallel embedded applications.In this paper we present performance execution tracer (PET), a monitoring and visualization toolkit specifically developed to measure and analyze this type of application. Special emphasis is placed on explaining how PET deals with the particular characteristics of these applications. In addition, in order to demonstrate the capabilities of PET, the measurement and analysis of a real application using this tool are described.
Wireless personal and local area networks
Authors: Thomas G. Zimmerman
Venue: Mobile commerce: technology, theory, and applications (2003)

Wireless communication is a technical and business revolution. Mobile phones are a common site in most cities around the world. Wireless personal and local area networks provide digital connectivity among mobile computing devices, including desktop, laptops and personal digital assistants (PDA). This chapter focuses on the competing standards that are vying for dominance in the booming wireless market. To prepare the reader, a broad review of wireless technology is provided. The various organizations that support the competition standards are outlined. The chapter concludes with some predictions, anticipating the outcomes of a very volatile marketplace.
Superluminals and the speed of light
Authors: Jason Wright
Venue: Smarandache notions (2002)

This brief paper was submitted as partial requirement for a Chemistry course. The topic was recommended to Dr. Kamala Sharma.