ppxscal/embedding_network huggingface dataset:
Constructing Railroad Blocking Plans to Minimize Handling Costs
Authors: Harry N. Newton, Cynthia Barnhart, Pamela H. Vance
Venue: Transportation Science (1998)

On major domestic railroads, a typical general merchandise shipment may pass through many classification yards on its route from origin to destination. At these yards, the incoming traffic, which may consist of a number of individual shipments, is reclassified (sorted and grouped together) to be placed on outgoing trains. Each reclassification incurs costs due to handling and delay. To prevent shipments from being reclassified at every yard they pass through, several shipments may be grouped together to form a block. A block has associated with an originÂ destination pair that may or may not be the origin or destination of any of the individual cars contained in the block. The objective of the railroad blocking problem is to choose which blocks to build at each yard and to assign sequences of blocks to deliver each shipment to minimize total mileage, handling, and delay costs. We model the railroad blocking problem as a network design problem in which yards are represented by nodes and blocks by arcs. Our model is intended as a strategic decision-making tool. We develop a column generation, branch-and-bound algorithm in which attractive paths for each shipment are generated by solving a shortest path problem. Our solution approach is unique in constraining the classification resources of each yard and simultaneously solving for different priority classes of shipments. We implement our algorithm and find near-optimal solutions in about one hour for the blocking problem of a large domestic railroad, in which the paths that shipments may take in the physical network are restricted. The resulting network design problem has 150 nodes, 1300 commodities, and 6800 possible arcs (blocks). We test the robustness of our solution on 19 test instances that are variations of the data for the real-world problems. If shipments are restricted to following one of a limited number of paths in the rail network, then, in four hours or less, our algorithm finds solutions within 0.4% of optimal for all test cases. Furthermore, the solutions obtained are no more than 3.9% from optimal even if all possible paths are allowed.
A Multiplicative Decomposition Property of the Screening-and-Selection Procedures of Nelson et al.
Authors: James R. Wilson
Venue: Operations Research (2001)

Recently, Nelson et al. (2001a, b) formulated a class of combined screening-and-selection procedures for identifying the simulated system with optimal expected response when the number of alternatives is finite, but large enough to render conventional ranking-and-selection procedures impractical. Under a certain key assumption, they derived anadditive decomposition lemma that provides a lower bound on the correct-selection probability when either the original or group-screening version of their combined screening-and-selection procedure is applied to randomly sampled normal populations with unknown and unequal variances. For both these procedures, we establish an improved lower bound on the correct-selection probability that is the product of (a) the probability that the best alternative will survive the first-stage screening procedure, and (b) the probability that the second-stage sampling-and-selection procedure will correctly identify the best alternative starting from the full set of alternatives. Thismultiplicative decomposition property offers a different perspective on the probabilistic structure of the entire class of combined screening-and-selection procedures developed by Nelson et al., and it does not require the key assumption of their additive decomposition lemma.
Algorithms for Radio Link Frequency Assignment: The Calma Project
Authors: Karen Aardal, Cor Hurkens, Jan Karel Lenstra, Sergey Tiourine
Venue: Operations Research (2002)

The radio link frequency assignment problem occurs when a network of radio links has to be established. Each link must be assigned an operating frequency from a given domain. The assignment has to satisfy certain restrictions so as to limit the interference between links. The number of frequencies used is to be minimized.Problems of this type were investigated within the CALMA project by a consortium consisting of research groups from Delft, Eindhoven, London, Maastricht, Norwich, and Toulouse. The participants developed optimization algorithms based on branch-and-cut and constraint satisfaction, and approximation techniques including a variety of local search methods, genetic algorithms, neural networks, and potential reduction. These algorithms were tested and compared on a set of real-life instances.
Generalized invexity and duality in multiobjective nonlinear programming
Authors: Laxminarayan Das, Sudarsan Nanda
Venue: The Korean Journal of Computational Applied Mathematics (2003)

The purpose of this paper is to study the duality theorems in cone constrained multiobjective nonlinear programming for pseudo-invex objectives and quasi-invex constrains and the constraint cones are arbitrary closed convex ones and not necessarily the nonnegative orthants.
Argumentation Rationality of Management Decisions
Authors: Sayan Chatterjee, Jagdip Singh, Axel V. Werder
Venue: Organization Science (1999)

This article is concerned with the assessment of the substantiation of management decisions in practice. The necessity for this undertaking derives from the fact that to be successful, management must choose the right extent of analysis for preparing major decisions. Testing this hypothesis requires the ability to measure the thoroughness of a decision preparation and to relate different levels of thoroughness to the success of the decision outcomes. In this paper, the author first presents the conceptual framework of argumentation rationality which makes it possible to measure the thoroughness of a decision preparation-or in other words, the soundness of reasons given for the decision. For a concretetrial usage, the concept is then combined with the methodology of account analysis introduced by Lewin (Lewin 1996, Lewin and Hunter 1996, Hunter 1999) for the research project on "New Organization Forms in the Information Age" (NOFIA). The arguments given explicitly in the accounts express rationales for management decisions and thus give hints on the intensity of the decision preparation. Using a simplified version of the measuring concept which assesses the argumentation rationality on three selected rationality determinants (pro/contra relation, depth of arguments, and breadth of arguments), two different types of rationality analyses are carried out to illustrate the fruitfulness of the approach. First, on the basis of 16 accounts concerning an important strategic decision of Daimler-Benz made in 1985 (becoming an integrated technology group), the arguments discussed during that time are identified and structured for assessing the substantiation of decision preparation. The developed structure of reasoning not only allows a formal evaluation, but in addition offers starting points for a substantial discussion of the change action. Secondly, 138 accounts from the German automotive industry of the years 1990-1997 are analyzed in order to identify first typical patterns of management argumentation. Based on the available empirical foundation, four types of reasoning are isolated, which differ characteristically with respect to the considered rationality determinants. The paper closes with a perspective on significant questions for further elaborating as well as employing the concept in future research.
Constraint and Integer Programming in OPL
Authors: Pascal Van Hentenryck
Venue: INFORMS Journal on Computing (2002)

In recent years, it has been increasingly recognized that constraint and integer programming have orthogonal and complementary strengths in stating and solving combinatorial optimization applications. In addition, their integration has become an active research topic. The optimization programming language OPL was a first attempt at integrating these technologies both at the language and at the solver levels. In particular, OPL is a modeling language integrating the rich language of constraint programming and the ability to specify search procedures at a high level of abstraction. Its implementation includes both constraint and mathematical programming solvers, as well as some cooperation schemes to make them collaborate on a given problem. The purpose of this paper is to illustrate, using OPL, the constraint-programming approach to combinatorial optimization and the complementary strengths of constraint and integer programming.
e-Commerce Metrics for Net-Enhanced Organizations: Assessing the Value of e-Commerce to Firm Performance in the Manufacturing Sector
Authors: Kevin Zhu, Kenneth L. Kraemer
Venue: Information Systems Research (2002)

In this study, we developed a set of constructs to measure e-commerce capability in Internet-enhanced organizations. The e-commerce capability metrics consist of four dimensions: information, transaction, customization, and supplier connection. These measures were empirically validated for reliability, content, and construct validity. Then we examined the nomological validity of these e-commerce metrics in terms of their relationships to firm performance, with data from 260 manufacturing companies divided into high IT-intensity and low IT-intensity sectors. Grounded in the dynamic capabilities perspective and the resource-based theory of the firm, a series of hypotheses were developed. After controlling for variations of industry effects and firm size, our empirical analysis found a significant relationship between e-commerce capability and some measures of firm performance (e.g., inventory turnover), indicating that the proposed metrics have demonstrated value for capturing e-commerce effects. However, our analysis showed that e-commerce tends to be associated with the increased cost of goods sold for traditional manufacturing companies, but there is an opposite relationship for technology companies. This result seems to highlight the role of resource complementarity for the business value of e-commerce--traditional companies need enhanced alignment between e-commerce capability and their existing IT infrastructure to reap the benefits of e-commerce.
A technique for improving dual-output domino logic
Authors: Sumant Ramprasad, Ibrahim N. Hajj, Farid N. Najm
Venue: IEEE Transactions on Very Large Scale Integration (VLSI) Systems (2002)

We present a technique, termed clock-generating (CG) domino, for improving dual-output domino logic that reduces area, clock load and power without increasing the delay. A delayed clock, generated from certain dual-output gates, is used to convert other dual-output gates to single output. Simulation results with ISCAS 85 benchmark circuits indicate an average reduction in area, clock load, and power of 17%, 20%, and 24%, respectively, over dual-output domino and a 48% power reduction for the largest circuit.
Reducing the blocking in two-phase commit with backup sites
Authors: P. Krishna Reddy, Masaru Kitsuregawa
Venue: Information Processing Letters (2003)

The blocking phenomena in two-phase commit (2PC) reduces the availability of the system as the blocked transactions keep all the resources until the recovery of the coordinator. The three-phase commit (3PC) protocol involves an extra round of message transmission to resolve the blocking problem. In this paper, we propose a backup commit (BC) protocol to reduce the blocking problem by attaching multiple backup sites to the coordinator site. In BC, after receiving responses from the participants, the coordinator quickly communicates the final decision to the backup sites, before it sends the final decision to the participants. When blocking occurs, the participant sites can terminate the transaction by consulting a backup site of the coordinator. The BC protocol resolves the blocking in most of the coordinator site failures without involving an expensive communication cycle as in 3PC. The simulation experiments indicate that the throughput performance of BC is close to 2PC.
A fuzzy-rough approach to the representation of linguistic hedges
Authors: Martine De Cock, Anna Maria Radzikowska, Etienne E. Kerre
Venue: Technologies for constructing intelligent systems: Tasks (2002)

We present a new representation for linguistic hedges using a framework of fuzzy rough sets. In traditional fuzzy-set theoretical representations, properties of objects such as old and experienced, are represented by a fuzzy set P, while linguistic hedges (i.e. expressions like very, more or less, rather) are modelled by means of some transformations applied to P. In contrast to these approaches, we propose a representation which allows us to express the meaning of a statement like "x is very P" also relative to mutual resemblances between objects in the domain of discourse. This allows for adequate context-dependent characteristics of objects. Technically, this is achieved by using fuzzy rough approximators with respect to fuzzy resemblance relations representing mutual resemblances between objects. We show that this framework allows for flexible representation of some linguistic terms.
Resonant holography
Authors: Arnab Sinha, George Barbastathis
Venue: Information Sciences&mdash;Informatics and Computer Science: An International Journal (2003)

We present a method to enhance the diffraction efficiency of a hologram by placing it inside a resonant optical cavity. The diffraction efficiency improves on account of constructive interference of the diffracted beams as the incident light undergoes multiple passes inside the resonator. The resonance condition in this case turns out to involve both mirror reflectivity and optical path length inside the cavity. Experimental results for a resonantly enhanced angle multiplexed holographic memory are shown.
Internet and society: a preliminary report
Authors: Norman H. Nie, Lutz Erbring
Venue: The digital divide: facing a crisis or creating a myth? (2001)

[Editor's note: This study is based on data on a panel of households recruited as a random telephone sample of the U.S. population. In order to use the Internet for the purpose of efficient multi-channel data collection, each household in the sample--with or without prior Internet connection--was equipped with a WebTV® set-top box, with free Internet access and email accounts. The data for the study were collected in December 1999, from a national random sample of 4,113 individuals in 2,689 panel households. The margin of sampling error is about ±1.5% for results from the complete survey, and about ±2.5% for the subset of Internet users.]
Application of graphical operation method to the dynamics and relative-motion problems
Authors: Tzong-Mou Wu, Cha'o-Kuang Chen
Venue: Applied Mathematics and Computation (2002)

In analyzing the dynamics and relative-motion problems, we usually need the "equations of motion" and some mathematical operations such as calculus, inner or cross product, etc. It will be a troublesome work for us to do the operation of algebra. For example, we must analyze carefully each component of the equations of motion about x, y, z axes in detail. This paper presents some simple graphical operation rules to overcome this imperfection. By means of graphical operation, we could exactly simplify necessary algebraic operations to get the simplified equations and obtain the equations of motion in compact forms. Two examples are included to illustrate this method.
The use of ill-defined problems for developing problem-solving and empirical skills in CS1
Authors: David Reed
Venue: Journal of Computing Sciences in Colleges (2002)

Education research has shown that an effective technique for developing problem-solving and critical-thinking skills is to expose students early and often to "ill-defined" problems in their field. An ill-defined problem is one that addresses complex issues and thus cannot easily be described in a concise, complete manner. Furthermore, competing factors may suggest several approaches to the problem, requiring careful analysis to determine the best approach. This paper describes a specific ill-defined problem that was successfully used as an assignment in a recent CS1 course. In completing this assignment, students actively participated in the entire process of problem solving and scientific inquiry, from the formulation of a hypothesis, to the design and implementation of experiments (via a program), to the collection and analysis of the experimental data. As a result, students developed empirical and critical-thinking skills, while also experiencing the use of programming as a tool for investigative inquiry. Experiences using this particular assignment will be discussed, as well as general approaches to identifying ill-defined problems and integrating them into a CS1 course.
Object-oriented classic data structures for CS2 in C#
Authors: H. Paul Haiduk
Venue: Journal of Computing Sciences in Colleges (2003)

For many years there has been substantial agreement that the content of the CS2 course should be a study of the classic data structures including, but not limited to, stacks, queues, trees, and tables. In recent years we have observed a move to the object-oriented programming paradigm for the CS2 course. At this point there is significant divergence as to the "best" programming language to use -- C++, Eiffel, Java, Oberon, Python, or Scheme, to name a few. Although many agree that to be truly object-oriented, a programming language must support (1) encapsulation of attributes and behavior in a user-defined class specification, (2) instantiation of objects of predefined and user-defined classes, (3) polymorphism, and (4) inheritance. From a survey of recent texts for the CS2 course, it appears that there is heavy emphasis on encapsulation and instantiation with some treatment of inheritance and little treatment of polymorphism. There is also significant treatment of generic container classes supported by template classes if the supporting language is C++. If the supporting language is Java, then the container typically manages objects of the type Object. This paper makes a case that the new Microsoft C# ((c)2001 Microsoft Corporation) language could be considered a viable candidate for the CS2 course since it supports user-defined class specifications with the encapsulation of attributes and behavior, instantiation of objects of predefined and user-defined classes, polymorphism and inheritance. Additionally, there is full support for exception handling using the now, well-known, try/catch/finally semantics. Further, there is support for dynamic memory allocation and deallocation. The language also makes the distinction between pass by reference and pass by value function/method parameters by obvious keywords in both the formal declarations and in the call. The language also supports namespaces for the organization of software components. And finally, the student or developer has full support for visual, event-driven, net-centric programming paradigm.This paper presents an implementation of a stack container ADT that is fully generic, that is, it may manage a collection of arbitrary objects that demonstrate polymorphic behavior.
Family of skewed distributions associated with the gene expression and proteome evolution
Authors: Vladimir A. Kuznetsov
Venue: Signal Processing (2003)

We study statistical distributions appearing in various genome-related phenomena, including the distribution of the transcript copy number in the transcriptome of eukaryotic cells and the distribution of the number of proteins containing a protein domain in proteomes of species. We found that the empirical distributions for all studied data sets are well fitted by a family of Pareto-like distribution functions whose shape depends in a predictable manner on the sample size. Such distributions are generated as limiting distributions in a Markov random process where the birth and death intensities are linear functions of events. We also propose a novel model of progressive evolution of a population in terms of the increase of the numbers of distinct components and their links in the system and we study evolution of the probability distribution of these links. Estimating two unknown parameters of this model allows us to describe the progressive evolution of the number of distinct protein domain sets and the number of proteins containing a given protein domain in the proteomes of 70 fully sequenced genome organisms. This model also predicts trends in proteome complexity evolution.
Substructural logic and partial correctness
Authors: Dexter Kozen, Jerzy Tiuryn
Venue: ACM Transactions on Computational Logic (TOCL) (2003)

We formulate a noncommutative sequent calculus for partial correctness that subsumes propositional Hoare Logic. Partial correctness assertions are represented by intuitionistic linear implication. We prove soundness and completeness over relational and trace models. As a corollary, we obtain a complete sequent calculus for inclusion and equivalence of regular expressions.
An Integrated Synchronization and Consistency Protocol for the Implementation of a High-Level Parallel Programming Language
Authors: Martin C. Rinard
Venue: Proceedings of the 10th International Parallel Processing Symposium (1996)

This paper presents experimental results that characterize the performance of the integrated synchronization and consistency protocol used in the implementation of Jade, an implicitly parallel language for coarse-grain parallel computation. The consistency protocol tags each replica of shared data with a version number. The synchronization algorithm computes the correct version numbers of the replicas of shared data that the computation will access. Because the protocol piggybacks the version number information on the synchronization messages, it generates fewer messages than standard update and invalidate protocols. This paper characterizes the performance impact of the consistency protocol by presenting experimental results for several Jade applications running on the iPSC/860 under several different Jade implementations.
Stochastic independence for upper and lower probabilities in a coherent setting
Authors: Giulianella Coletti, Romano Scozzafava
Venue: Technologies for constructing intelligent systems: tools (2002)

In this paper we extend to upper and lower probabilities our approach to independence, based solely on conditional probability (in a coherent setting). Most difficulties arise (when this notion is put forward in the classical framework) either from the introduction of marginals for upper and lower probabilities (often improperly called, in the relevant literature, "imprecise" probabilities) when trying to extend to them the "product rule", or from the different ways of introducing conditioning for upper and lower probabilities. Our approach to conditioning in the context of "imprecise" probabilities is instead the most natural: in fact its starting point refers to a direct definition (through coherence) of the "enveloping" conditional "precise" probabilities. The discussion of some critical examples seems to suggest that the intuitive aspects of independence are better captured by referring to just one (precise) probability than to a family (such as that one singling-out a lower or upper probability).
Resource Constrained Chain Scheduling of Uet Jobs on Two Machines
Authors: W. Kubiak, J. Blazewicz, M. Dror, N. Katoh, H. Rock
Venue: Operations Research (1998)

A well-known technique for solving scheduling problems with two identical parallel processors and unit execution time jobs under a makespan minimization criteria involves finding maximum cardinality matchings in the graph associated with the problem, and then using these matchings to create optimal schedules. For some problem instances, however, this method will not work, since the problems are NP-hard. In this note, a previously open problem involving additional resource constraints is shown to have a polynomial algorithm using cardinality matching method.