ppxscal/embedding_network huggingface dataset:
A Set Partitioning Approach to the Crew Scheduling Problem
Authors: A. Mingozzi, M. A. Boschetti, S. Ricciarde, L. Bianco
Venue: Operations Research (1999)

The crew scheduling problem (CSP) appears in many mass transport systems (e.g., airline, bus, and railway industry) and consists of scheduling a number of crews to operate a set of transport tasks satisfying a variety of constraints. This problem is formulated as a set partitioning problem with side constraints (SP), where each column of the SP matrix corresponds to a feasible duty, which is a subset of tasks performed by a crew. We describe a procedure that, without using the SP matrix, computes a lower bound to the CSP by finding a heuristic solution to the dual of the linear relaxation of SP. Such dual solution is obtained by combining a number of different bounding procedures. The dual solution is used to reduce the number of variables in the SP in such a way that the resulting SP problem can be solved by a branch-and-bound algorithm. Computational results are given for problems derived from the literature and involving from 50 to 500 tasks.
Experiences with developing a computer security information assurance curriculum
Authors: Thomas Bacon, Rahul Tikekar
Venue: Journal of Computing Sciences in Colleges (2003)

Attacks on the computing infrastructure have gained prominence as the world harnessed the business transaction capability of the Internet in the last few years. Denial of service attacks and viruses cripple systems, making them unavailable to users and often destroying data. Information theft allows the thief to assume false identities, steal trade secrets and classified information, and perform transactions with accounts owned by others. There is a shortage of skilled computer security professionals capable of reducing vulnerabilities in computing systems.This paper describes the process of creating a computer security and information assurance (CSIA) curriculum Bachelors degree. The process begins with determining goals, followed by developing a plan of action and ends with determining a curriculum consisting of new computer science and interdisciplinary synthesis courses.
Hewlett-Packard Uses Operations Research to Improve the Design of a Printer Production Line
Authors: Mitchell Burman, Stanley B. Gershwin, Curtis Suyematsu
Venue: Interfaces (1998)

As Hewlett-Packard Corporation installed a system for manufacturing ink-jet printers in Vancouver, Washington, in 1993, it realized that the system would not be fast enough or reliable enough to meet its production goals. At the time, the market for ink-jet printers was exploding, and any incremental printer shipments would translate directly into market share and revenue gains. The company undertook a simulation project to develop recommendations for design changes to improve the system performance but concluded that that project would take too long to be useful. MIT researchers used analytical methods to predict capacity and to determine the sizes and locations of buffers that would increase capacity at the cost of a minor increase in inventory. HP's implementation of this work yielded incremental revenues of about $280 million in printer sales and additional revenues from ancillary products, replacement ink-jet cartridges, media, and related items. Productivity increased about 50 percent, making the assembly of the print engine cost competitive. Finally, HP developed a method of creating rapid and effective system designs in the future.
Commutator-free Lie group methods
Authors: Elena Celledoni, Arne Marthinsen, Brynjulf Owren
Venue: Future Generation Computer Systems (2003)

We propose a new format of Lie group methods which does not involve commutators and which uses a much lower number of exponentials than those proposed by Crouch and Grossman. By reusing flow calculations in different stages, the complexity is even further reduced. We argue that the new methods may be particularly useful when applied to problems on homogeneous manifolds with large isotropy groups, or when used for stiff problems. Numerical experiments verify these claims when applied to a problem on the orthogonal Stiefel manifold, and to an example arising from the semidiscretization of a linear inhomogeneous heat conduction problem.
Modeling spatial variability of 137Cs surface activity in a mountain zone
Authors: J. M. Métivier, L. Pourcelot
Venue: Development and application of computer techniques to environmental studies (2002)

Based on 137Cs surface activity field studies performed on a workshop zone, we succeeded in identifying the main criterion permitting surface activity modeling to be extended. Geomorphometric data derived from the Digital Elevation Model (slope, aspect) was combined together with land use.Geographical Information System software allowed us to gather together, organize and analyze the spatial variability of these data sets. Surface activity in all the catchment basins were modeled using a mapping function tree that symbolizes treatment sequences. Subsequently, a map validation step was performed via soil sampling and measuring.
Relationship Between Strong Monotonicity Property, P2-Property, and the Gus-Property in Semidefinite Linear Complementarity Problems
Authors: T. Parthasarathy, D. Sampangi Raman, B. Sriparna
Venue: Mathematics of Operations Research (2002)

In a recent paper on semidefinite linear complementarity problems, Gowda and Song (2000) introduced and studied theP-property,P2-property, GUS-property, and strong monotonicity property for linear transformationL: S n?S n , whereS nis the space of all symmetric and realn x n matrices. In an attempt to characterize theP2-property, they raised the following two questions: (i) Does the strong monotonicity imply theP2-property? (ii) Does the GUS-property imply theP2-property? In this paper, we show that the strong monotonicity property implies theP2-property for any linear transformation and describe an equivalence between these two properties for Lyapunov and other transformations. We show by means of an example that the GUS-property need not imply theP2-property, even for Lyapunov transformations.
How useful is lifelong evolution for robotics?
Authors: Joanne Walker, Myra Wilson
Venue: Proceedings of the seventh international conference on simulation of adaptive behavior on From animals to animats (2002)

This paper investigates a system that uses a genetic algorithm to train a robot for a generalised test environment, then an evolutionary strategy to investigate the effect of continuing the evolution as the robot progresses with its task.The paper concludes that continuing evolution after a training phase has an important role to play in producing truly adaptive robots.
Addendum to "Presolve Analysis of Linear Programs Prior to Applying an Interior Point Method"
Authors: Csaba Mészáros, Jacek Gondzio
Venue: INFORMS Journal on Computing (2001)

In this note we point out that the assumptions of Propositions 1 and 2 in Gondzio (1997) are not sufficiently restrictive. We give an example that demonstrates the lack of precision in these propositions and discuss the necessary modifications of the propositions.
A Statistical Test For Nested Radial Dea Models
Authors: Jesús T. Pastor, José L. Ruiz, Inmaculada Sirvent
Venue: Operations Research (2002)

Some problems in economics, operations research, and engineering may be approached by means of a pair of radial DEA models that are nested, i.e., that the set of constraints of one of them is included in that of the other. In this paper we have focused on analyzing the marginal role of a given variable, calledcandidate, with respect to the efficiency measured by means of a DEA model. First, we have defined a newefficiency contribution measure (ECM), which finally compares the efficiency scores of the two radial DEA models differing in the candidate. This can be either one input or one output. Then,based on ECM, we have also approached the problem from a statistical point of view. To be precise, we have developed a statistical test that allows us to evaluate the significance of the observed efficiency contribution of the candidate. Eventually, solving this test may provide some useful insights in order to decide the incorporation or the deletion of a variable into/from a given DEA model, on the basis of the information supplied by the data. Two procedures for progressive selection of variables were designed by sequentially applying the test: a forward selection and a backward elimination. These can be very helpful in the initial selection of variables when building a radial DEA model.
The institutionalization of hacking practices
Authors: Yuwei Lin
Venue: Ubiquity (2003)

Diverse choices and practices shape innovation patterns in software development
Towards virtual reality for the masses: 10 years of research at Disney's VR studio
Authors: Mark Mine
Venue: Proceedings of the workshop on Virtual environments 2003 (2003)

The VR Studio was founded in 1992 to explore the potential of Virtual Reality technology for theme park attractions. This paper presents an overview of the VR Studio's history, from the location-based entertainment attractions developed for DisneyQuest, to research in using virtual reality technology for theme park design. The goal is to present many of the lessons learned during 10 years of building interactive virtual worlds. In particular, the paper will focus on the challenge of creating location-based virtual reality attractions for the mass audience.
Influence of environment on population health in Copsa Mica
Authors: G. Pandi, V. Sorocovschi, M. Vigh
Venue: Development and application of computer techniques to environmental studies (2002)

Copsa Mica is the town with the highest degree of pollution in Romania. A number of highly polluted industrial units have appeared in a concentrated area since 1935. Between 1950 and 1980 the town developed at high speed due to the policy of forced industrialization and eventually the number of inhabitants declined. Because of the faulty distribution of industries, the natural environmental conditions facilitate the spreading of polluting agents not only inside the town's perimeter but also in the neighboring areas. The most intensive polluting agents are the sulphur dioxides, lead, the solid particles in suspension, cadmium, and other similar substances, which are present in the atmosphere, in the subsurface and surface water, in the soil and on the vegetation. Pollution affects the health of the local population as well, mostly that of children. The toxic substances enter the human body through the polluted air, water and food from the affected areas. The spatial and temporal variation of pollution ranges between wide limits according to the intensity of industrial pollution and the environmental conditions. The concentrations sometimes exceed ten times the limit of acceptance.
Market Power and Power Markets
Authors: Jürgen Weiss
Venue: Interfaces (2002)

Market power is a prominent issue in the current debate about electricity industry restructuring. Market experiments I conducted with industry subjects via the Internet show the impact of seller concentration, demand-side bidding, and transmission constraints on competition in simulated electricity markets. Realistic modeling of the transmission grid revealed opportunities to exercise market power not found in simpler experimental designs. In particular, increasing the number of sellers in a market did not necessarily reduce market power as standard theory suggests. Rather, locational advantages allowed some players to maintain profits near monopoly levels even when seller concentration was at levels generally considered competitive. The implication is that divestiture of existing local monopolies may not be enough to make electricity markets competitive. I confirm the positive impact of demand-side bidding on competition.
Clock driven scheme to initialize the sequence number
Authors: Chong Kim
Venue: Ubiquity (2003)

Using TCP deal with delayed duplicates of both old and new connections
Re-engineering library education
Authors: Vicki L. Gregory
Venue: Building a virtual library (2003)

The revolutionary changes in the educational curriculum for schools of library and information science being evinced by the exponential expansion of computer-based technologies require a reexamination of the skills and expertise needed to be acquired by the next wave of academic librarians. This is critical in order that they may continue to be able to provide information services and resources to the academic communities within which those librarians will practice their profession. In addition, it is important to meet emerging educational needs in terms of various multiculturalism and diversity issues that are arising today as well as a thorough understanding of research theory and practice. Implicit in these examinations is a need to review the way library school faculty will be teaching, using newer technologies including Web-delivery of courses, and how faculty should exhibit the skills needed in order to be able to deliver courses using the new technology-centered methods. Finally, this chapter will emphasize the importance of continuing education for future academic librarians and current professionals.
Incentive-Compatible Pricing for a Service Facility with Joint Production and Congestion Externalities
Authors: Stephen M. Gilbert, Z. Kevin Weng, Albert Y. Ha
Venue: Management Science (1998)

This paper considers the pricing problem of a service facility when services are jointly produced by the customers and the facility. Building on the work of Mendelson (1985), we model the facility as a GI/GI/1 queue with customer-chosen service rates and linear delay costs. We show that the service rates chosen by the customers, based on their self-interest, are always suboptimal for the facility due to congestion externalities. We derive optimal incentive-compatible pricing schemes that can achieve optimal arrival rates and induce customers to choose optimal service rates. For the case of systemwide net-value maximization, we show that the optimal incentive-compatible pricing scheme consists of a variable fee that is proportional to the actual service time and a fixed rebate that is equal to a customer1s expected delay cost in the queue. For the case of profit maximization of the facility, we show that the optimal pricing scheme again consists of a fixed fee and a variable fee. One insight from our analysis is that it may be appropriate for a service facility to reimburse each customer for his actual delay cost in the queue.
Robust numerical integration and pairwise independent random variables
Authors: Hiroshi Sugita
Venue: Journal of Computational and Applied Mathematics (2002)

A numerical integration method by means of random samples is called robust, if the variance of its error is as small as that of the i.i.d.-sampling for any integrand. To reduce the randomness of robust numerical integration, we use pairwise random samples instead of i.i.d, samples. Among others, we recommend the discrete random Weyl sampling for the quick generation of pairwise independent samples.
Adaptive smooth scattered-data approximation for large-scale terrain visualization
Authors: Martin Bertram, Xavier Tricoche, Hans Hagen
Venue: Proceedings of the symposium on Data visualisation 2003 (2003)

We present a fast method that adaptively approximates large-scale functional scattered data sets with hierarchical B-splines. The scheme is memory efficient, easy to implement and produces smooth surfaces. It combines adaptive clustering based on quadtrees with piecewise polynomial least squares approximations. The resulting surface components are locally approximated by a smooth B-spline surface obtained by knot removal. Residuals are computed with respect to this surface approximation, determining the clusters that need to be recursively refined, in order to satisfy a prescribed error bound. We provide numerical results for two terrain data sets, demonstrating that our algorithm works efficiently and accurate for large data sets with highly non-uniform sampling densities.
Composition and abstraction
Authors: Antti Valmari
Venue: Modeling and verification of parallel processes (2001)

This article is a tutorial on advanced automated process-algebraic verification of concurrent systems, and it is organised around a case study. The emphasis is on verification methods that rely on the inherent compositionality of process algebras. The fundamental concepts of labelled transition systems, strong bisimilarity, synchronous parallel composition, hiding, renaming, abstraction, CFFD-equivalence and CFFD-preorder are presented as the case study proceeds. The necessity of presenting assumptions about the users of the example system is discussed, and it is shown how CFFD-preorder supports their modelling. The assumptions are essential for the verification of so-called liveness properties. The correctness requirements of the system are stated, presented in linear temporal logic, and distributed to a number of more "localised" requirements. It is shown how they can be checked with the aid of suitably chosen CFFD-abstracted views to the system. The state explosion problem that hampers automatic verification is encountered. Compositional LTS construction, interface specifications and induction are used to solve the problem and, as a result, an infinite family of systems is verified with a limited amount of effort.
Global Newton-type methods and semismooth reformulations for NCP
Authors: S. Pieraccini, M. G. Gasparo, A. Pasquali
Venue: Applied Numerical Mathematics (2003)

It is known that a nonlinear complementarity problem (NCP) can be reformulated as a semismooth system of nonlinear equations by using a so-called NCP-function. Global Newton-type methods for solving NCP via semismooth reformulation need to use a merit function, which is usually required to be continuously differentiable. In this paper we present a global Newton-type method which does not require the differentiability for the merit function used in the line-search procedure. The method is used to numerically compare the effectiveness of two NCP-functions widely discussed in literature, the minimum function and the Fischer-Burmeister function. The results on several examples allow to gain some new acquaintance of the respective numerical advantages of the two functions.
Data partitioning and load balancing in parallel disk systems
Authors: Peter Scheuermann, Gerhard Weikum, Peter Zabback
Venue: The VLDB Journal &mdash; The International Journal on Very Large Data Bases (1998)

Parallel disk systems provide opportunities for exploiting I/O parallelism in two possible ways, namely via inter-request and intra-request parallelism. In this paper, we discuss the main issues in performance tuning of such systems, namely striping and load balancing, and show their relationship to response time and throughput. We outline the main components of an intelligent, self-reliant file system that aims to optimize striping by taking into account the requirements of the applications, and performs load balancing by judicious file allocation and dynamic redistributions of the data when access patterns change. Our system uses simple but effective heuristics that incur only little overhead. We present performance experiments based on synthetic workloads and real-life traces.
Introducing chronicity: a quantitative measure of self/non-self in immune response
Authors: Yoshiki Kashimori, Yoshihiro Ochi, Mei Hong Zheng, Takeshi Kambara
Venue: Proceedings of the seventh international conference on simulation of adaptive behavior on From animals to animats (2002)

This paper presents a new theory of how lymphocyte-antigen interaction is governed. We present "chronicity', a quantitative record of previous lymphocyte-antigen interactions, which is used to regulate lymphocyte behavior. A simplified model of the immune response, incorporating chronicity, is described. When the chronicity of a lymphocyte increases with the interaction and gets beyond the lower threshold, the lymphocyte can proliferate. Simulations using this model show that nonself antigens cause lymphocyte proliferation which destroys the antigen and results in the creation of a 'memory' of this antigen in the form of a pool of lymphocytes of correct specificity. Equally importantly, 'self antigens are not destroyed. The lymphocytes attacking specifically the antigens increase quite rapidly their chronicity through the continuous interaction with the antigens that are rare of change in concentration. When the chronicity gets beyond the upper threshold, the lymphocytes get in the tolerance state ensuring non destruction of self antigens. The lymphocytes secrete actively negative cytokines which reduce the activation of other lymphocytes. This self/non-self discrimination ability and overall system behavior is similar to that observed in real immune systems.
Statistical models of topical content
Authors: J. P. Yamron, L. Gillick, P. van Mulbregt, S. Knecht
Venue: Topic detection and tracking: event-based information organization (2002)

In this chapter we explore the behavior of two different statistical models, one based on simple unigrams and another based on the beta-binomial distribution, as applied to the problem of modeling story generation. We describe how these models can be incorporated into information extraction applications, particularly Tracking and Detection engines built for the Topic Detection and Tracking evaluations sponsored by DARPA. Tracking systems based on the two models have complementary strengths and weaknesses: a Beta-Binomial system yields high precision at high decision threshold, but performance quickly degrades as the threshold drops; a Unigram system is not as strong at high decision threshold, but is very good at suppressing false-alarms at lower threshold. We will describe the features of these systems that give rise to this behavior, and discuss ways that each system might be improved by borrowing from the other. We will also discuss our Detection system, and how improvements in Tracking should lead to improvements in Detection.
Fuzzy recognizers and recognizable sets
Authors: H. V. Kumbhojkar, S. R. Chaudhari
Venue: Fuzzy Sets and Systems (2002)

In this paper, the concepts of fuzzy recognizers and recognizable sets are studied and their relationship with various products of fuzzy finite state machines is established. The tools necessary for such study are developed. The ideas of reversal, inverse image, accessible part, coaccessible part, trim part regarding fuzzy recognizers are introduced and their properties are discussed.
TIMBER: A native XML database
Authors: H. V. Jagadish, S. Al-Khalifa, A. Chapman, L. V. S. Lakshmanan, A. Nierman, S. Paparizos, J. M. Patel, D. Srivastava, N. Wiwatwattana, Y. Wu, C. Yu
Venue: The VLDB Journal &mdash; The International Journal on Very Large Data Bases (2002)

This paper describes the overall design and architecture of the Timber XML database system currently being implemented at the University of Michigan. The system is based upon a bulk algebra for manipulating trees, and natively stores XML. New access methods have been developed to evaluate queries in the XML context, and new cost estimation and query optimization techniques have also been developed. We present performance numbers to support some of our design decisions. We believe that the key intellectual contribution of this system is a comprehensive set-at-a-time query processing ability in a native XML store, with all the standard components of relational query processing, including algebraic rewriting and a cost-based optimizer.