ppxscal/embedding_network huggingface dataset:
The Simultaneous Planning of Production, Capacity, and Inventory in Seasonal Demand Environments
Authors: James R. Bradley, Bruce C. Arntzen
Venue: Operations Research (1999)

Manufacturing managers often address capacity and inventory decisions separately, thus ignoring the interaction between capacity and inventory within a manufacturing system. The separation of these two decisions can lead to an imbalance of capacity and inventory investment. We develop a model that simultaneously plans capacity investment, inventory investment, and the production schedule using return on assets as the objective to maximize. An algorithm is developed that optimizes a fractional objective function for a mixed-integer program. The model was applied at an electronics manufacturer and at a manufacturer of office supplies.
Hamiltonian double Latin squares
Authors: A. J. W. Hilton, M. Mays, C. A. Rodger, C. St. J. A. Nash-Williams
Venue: Journal of Combinatorial Theory Series B (2003)

A double latin square of order 2n on symbols σ1, ..., σn an is a 2n × 2n matrix A = (aij) in which each aij is one of the symbols σ1, ..., σn and each σk occurs twice in each row and twice in each column. For k = 1,...,n let B(A, σk) be the bipartite graph with vertices ρ1,..., ρ2n, c1, ..., c2n and 4n edges [ρi, cj] corresponding to ordered pairs (i,j) such that aij = σk. We say that A is Hamiltonian if B(A, σk) is a cycle of length 4n for k = 1 ,..., n. Two double latin squares (aij), (a'ij) of order 2n on symbols σ1,...,σn are said to be orthogonal if for each ordered pair (σh, σk) of symbols there are four ordered pairs (i,j) such that aij = σh, a'ij = σk.We explore ways of constructing Hamiltonian double latin squares (HLS), symmetric HLS, sets of mutually orthogonal HLS and pairs of orthogonal symmetric HLS. We identify those arrays which can be obtained from HLS by amalgamating rows and amalgamating columns in a certain sense, and we prove a similar result concerning symmetric arrays obtainable in this way from symmetric HLS. These results can be proved either by using matroids or by a more elementary method, and we illustrate both approaches. From these results we deduce a characterisation of those matrices which are submatrices of HLS on n symbols, a similar result concerning symmetric submatrices of symmetric HLS and some related results. Much of our discussion uses graph-theoretic language, since HLS on n symbols are equivalent to decompositions of K2n,2n into Hamiltonian cycles and symmetric HLS on n symbols are equivalent to decompositions of K2n into Hamiltonian paths (and these are equivalent to decompositions of K2n+1 into Hamiltonian cycles).
Impact of tree mortality in optimal control and parameter selection problems in forest stand management
Authors: O. Chikumbo, I. M. Y. Mareels
Venue: Development and application of computer techniques to environmental studies (2002)

Two mathematical formulations for determining optimal silvicultural regimes and initial number of trees at planting for a forest stand are compared. One formulation incorporates competition mortality of trees and the other does not. The comparison is done for a high site quality and low site quality stands in order to account for any influence that may result from geographical variations. The conventional wisdom is that competition mortality is of no real concern in intensively managed forests, and we set out to investigate this by experiment. The formulations are based on Pontryagin's maximum principle, using dynamical models in each case, for simulating the state dynamics of the optimal control systems.
Morality and Computers: Attitudes and Differences in Judgments
Authors: Urs E. Gattiker, Helen Kelley
Venue: Information Systems Research (1999)

Business ethics is an emerging area of research in many subfields of management, including information systems (IS). Empirical IS research has studied differences in users' attitudes and in moral judgments regarding ethical computer-related behavior. This study applied the "domains of morality" approach to determine how users felt about certain computer-related behaviors. Vignettes describing ethical dilemmas involving computer technology (e.g., up-loading a computer virus on an electronic network/bulletin board system) were presented to a sample of Internet users. The research findings offered several interesting and, in some cases, unexpected results. The empirical results indicated that older computer users have a less permissive sense of what is right and wrong for an illegal game. When computers were used to test a banned game, men and women differed in their assessment of its appropriateness. A surprising finding was that participants were not likely to endorse civil liberties, and were more concerned about the harm to, and violations of, social norms when the scenario described a situation involving a computer virus. How users perceive, prejudge, and discriminate computer ethics and abusive computer actions raises numerous questions and implications for IS researchers, IS practitioners, and policy makers. The results of this study foster a better understanding of Internet users' moral categorization of specific computer behaviors and, hopefully, help to further reduce risks and vulnerabilities of systems by identifying computer actions deemed ethically acceptable by users. Opportunities for IS researchers to further explore this timely issue are also discussed.
Towards A Culturally Sensitive Approach To Organization Structuring: Where Organization Design Meets Organization Development
Authors: Paul Bate, Raza Khan, Annie Pye
Venue: Organization Science (2000)

This article describes an holistic model of intervention geared to achieving transformational change by interweaving culture and structure through the warp and weft of leadership processes. That is, it brings together organization design and organization development by advocating a culturally sensitive approach to organization structuring. Our emphasis is on process throughout and our thesis is based on empirical evidence. We undertook a lengthy action research project (which we prefer to call "action ethnography") at a large hospital trust in England. In the process of elaborating this field study, we move from an organization which was seen to be "gridlocked" and to have "lost its steering capacity", through one which was bringing development and design together by way of pilot projects and transitional structures, to one where collective dialogue and debate finally led to some collective and sensible sensemaking.Exploring this relationship between culture and structure enables us to put people back into design and with them, their meanings, aspirations and assumptions. It also means that we are careful to avoid detailing specific design choices or offering organizational archetypes: this article is primarily about the process issues that surround redesign rather than organization design per se, as indeed any redesign is ultimately highly specific and context-driven. Instead, however, we articulate a four-phase change model, focusing on the delicate processes by which to reframe the culture-structure relationship, enabling an organization to move towards fundamental change.
Configurable parallel memory architecture for multimedia computers
Authors: Kimmo Kuusilinna, Jarno Tanskanen, Timo Hämäläinen, Jarkko Niittylahti
Venue: Journal of Systems Architecture: the EUROMICRO Journal (2002)

This paper presents a novel parallel memory architecture for multimedia computers. Applying a configurable or programmable addressing circuitry capable of parallel memory accesses, the memory management of multimedia applications can be enhanced. Necessary computer architecture changes to virtual address representation, paging, virtual memory, address computation circuitry and data permutation are discussed. These changes allow the memory to be partitioned for different access functions. In addition, the same memory area can be accessed by multiple access patterns. Therefore, a general-purpose computing system that is capable of exploiting the repeating memory access patterns in its applications can be built. Performance of the configurable parallel memory architecture (CPMA) is analyzed in the case of a selection of algorithms from a video encoder. These motion estimation algorithms and zigzag scanning benefit from the multiple memory access functions, which is apparent from the comparisons to the traditional sequential memory accesses.
Asymtotic behaviour of the viscous Cahn-Hilliard equation
Authors: S. M. Choo, S. K. Chung
Venue: The Korean Journal of Computational Applied Mathematics (2003)

Analytical solutions for the viscous Cahn-Hilliard equation are considered. Existence and uniqueness of the solution are shown. The exponential decay of the solution in H2-norm, which is an improvement of the result in Elliott and Zheng[5]. We also compare the early stages of evolution of the viscous Cahn-Hilliard equation with that of the Cahn-Hilliard equation, which has been given as an open question in Novick-Cohen[8].
Tissue P systems
Authors: Carlos Martín-Vide, Gheorghe Paun, Juan Pazos, Alfonso Rodríguez-Patón
Venue: Theoretical Computer Science (2003)

Starting from the way the inter-cellular communication takes place by means of protein channels (and also from the standard knowledge about neuron functioning), we propose a computing model called a tissue P system, which processes symbols in a multiset rewriting sense, in a net of cells. Each cell has a finite state memory, processes multisets of symbol-impulses, and can send impulses ("excitations") to the neighboring cells. Such cell nets are shown to be rather powerful: they can simulate a Turing machine even when using a small number of cells, each of them having a small number of states. Moreover, in the case when each cell works in the maximal manner and it can excite all the cells to which it can send impulses, then one can easily solve the Hamiltonian Path Problem in linear time. A new characterization of the Parikh images of ETOL languages is also obtained in this framework. Besides such basic results, the paper provides a series of suggestions for further research.
Efficient Systolic Array Mapping of FIR Filters Used in PAM-QAM Modulators
Authors: A. Chorevas, D. Reisis
Venue: Journal of VLSI Signal Processing Systems (2003)

This paper presents efficient techniques for mapping FIR filter computation circuits for PAM and QAM modulators onto systolic arrays. The exploitation of the inherent symmetry of these problem instances and the use of Look-Up Tables (L.U.T.) in conjunction with the use of systolic architectures, increases the performance while keeping the VLSI area minimal. Exploiting parallelism and pipelining enhances the throughput and results in linear expandability of the FIR filter with respect to the bit accuracy and to the stage count.
Channel Dynamics Under Price and Service Competition
Authors: Andy A. Tsay, Narendra Agrawal
Venue: Manufacturing Service Operations Management (2000)

This paper studies a distribution system in which a manufacturer supplies a common product to two independent retailers, who in turn use service as well as retail price to directly compete for end customers. We examine the drivers of each firm's strategy, and the consequences for total sales, market share, and profitability. We show that the relative intensity of competition with respect to each competitive dimension plays a key role, as does the degree of cooperation between the retailers. We discover a number of insights concerning the preferences of each party regarding competition. For instance, there will be circumstances under which both retailers would prefer an increase in competitive intensity. Our analysis generalizes existing knowledge about manufacturer wholesale pricing strategies, and rationalizes behaviors that would not be evident without both price and service competition. Finally, we characterize the structure of wholesale pricing mechanisms that can coordinate the system, and show that the most commonly used formats (those that are linear in the order quantity) can achieve coordination only under very limiting conditions.
Improvements to the general number field sieve for discrete logarithms in prime fields: a comparison with the Gaussian integer method
Authors: Antoine Joux, Reynald Lercier
Venue: Mathematics of Computation (2003)

In this paper, we describe many improvements to the number field sieve. Our main contribution consists of a new way to compute individual logarithms with the number field sieve without solving a very large linear system for each logarithm. We show that, with these improvements, the number field sieve outperforms the gaussian integer method in the hundred digit range. We also illustrate our results by successfully computing discrete logarithms with GNFS in a large prime field.
A national science foundation supported undergraduate CSMET research project
Authors: R. Stephen Dannelly, Carl W. Steidley
Venue: Journal of Computing Sciences in Colleges (2002)

This paper describes a program at Texas A&M University B Corpus Christi which seeks to involve a substantial number of undergraduate students in active research. This program receives funding from the National Science Foundation, grant number DUE-0094898. Students receive a small stipend in return for participating in one of several multidisciplinary projects. Projects include funded and unfunded research conducted by computer science, mathematics, engineering technology, and geographic information science professors. The goal of the project is to promote student learning and retention.
Affective gaming: measuring emotion through the gamepad
Authors: Jonathan Sykes, Simon Brown
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

In search of suitable methods for measuring the affective state of video-game players, this study investigates the hypothesis that the player's state of arousal will correspond with the pressure used to depress buttons on a gamepad. A video game was created that would detect the force of each button press during play. It was found that as the difficulty level of the game increased, players would hit the gamepad buttons significantly harder.
Abstracts for the 1998 Transportation Science Section
Authors: Merja Halme, Tarja Joro, Pekka Korhonen, Seppo Salo, Jyrki Wallenius, Siamak A. Ardekani
Venue: Transportation Science (1999)

The TSS Dissertation Prize Competition is the oldest and most prestigious competition for doctoral dissertations in the transportation science area. On behalf of the TSS dissertation prize committee, I am pleased to provide this report on the 1998 competition. Eligible doctoral dissertations were those completed and submitted between June 1, 1997 and May 31, 1998 in the area of transportation science. To be considered, a dissertation had to be nominated by the thesis supervisor. This year, eight dissertations were submitted for consideration by the judging committee, which was chaired by Professor Siamak A. Ardekani, The University of Texas at Arlington, and consisted of: 1) Professor Jay Jayakrishnan, University of California at Irvine; 2) Professor Srinivas Peeta, Purdue University; 3) Professor Paolo Toth, University of Bologna-Italy; 4) Professor Garrett J. van Ryzin, Columbia University I would like to extend my sincere thanks to the judges for the time and effort they devoted to the difficult task of judging these entries. The quality of all the theses submitted was excellent and the choices were difficult. The awards were announced at the Fall meeting of INFORMS in Seattle. The First Prize winner was Dr. Gianpaolo Ghiani of The Universita degli Studi di Napoli "Federico II." An honorable mention was awarded to Dr. Robert L. Hoffman of the University of Maryland at College Park. It is important to remember that the submissions to the TSS Dissertation competition are already distinguished by the fact that they have been nominated for the award. Each makes a unique and valuable contribution to transportation science, and allentrants and their advisors deserve warmest congratulations.
Multi-drop path model for multicast routing and wavelength assignment
Authors: Shuguang Yan, Jitender Deogun
Venue: Information Sciences&mdash;Informatics and Computer Science: An International Journal (2003)

We investigate the problem of multicast routing and wavelength assignment under the multi-drop path model (MRWA-MP). In a multi-drop path model, multiple paths are employed to establish a multicast session and each path can drop signals at no more than a predefined number of destination nodes. Given a network topology and a multicast session, the MRWA-MP problem is to minimize the number of wavelengths used to establish the multicast session and, as an auxiliary objective, minimize the number of fibers used. We derive bounds for both objectives. The lower bound on the number of wavelengths derived is tighter and thus more accurate than that in recent papers. To gain an insight into the complexity of the MRWA-MP problem, we formulate it as a mixed integer linear programming (MILP) problem and solve it using CPLEX integer optimizer. Our experience indicates that this problem can easily overwhelm even a state-of-the-art computing facility. To solve the MRWA-MP problem efficiently, we develop a heuristic, MFBH, based on the Edmonds-Karp maximum flow algorithm. Through experiments, we show that the MFBH heuristic achieves the lower bound on the number of wavelengths in almost all instances of the real-life and randomly generated networks that we tested. Furthermore, MFBH tends to use fewer fibers when the maximum number of drops allowed on a single path decreases, the number of destination nodes in a multicast session increases, or the connectivity of the network decreases.
Break-up and no break-up in a family of models for the evolution of viscoelastic jets
Authors: Marco A. Fontelos
Venue: Zeitschrift f&uuml;r Angewandte Mathematik und Physik (ZAMP) (2003)

The goal of this paper is to study the conditions under which break-up of a thin viscoelastic jet is inhibited or, oppositely, to provide families of self-similar break-up solutions emerging in the evolution. The fluid is a polymeric solution and the constitutive relation we consider is of the Johnson-Segalman type which contains one parameter. The models under consideration are the limits of the well know one-dimensional model when the viscosity of the solvent goes to zero or to infinity and when the Deborah number is very large. Some considerations on the stationary and travelling wave solutions of the models are also presented.
Path-protection routing and wavelength assignment (RWA) in WDM mesh networks under duct-layer constraints
Authors: Hui Zang, Canhui Ou, Biswanath Mukherjee
Venue: IEEE/ACM Transactions on Networking (TON) (2003)

This study investigates the problem of fault management in a wavelength-division multiplexing (WDM)-based optical mesh network in which failures occur due to fiber cuts. In reality, bundles of fibers often get cut at the same time due to construction or destructive natural events, such as earthquakes. Fibers laid down in the same duct have a significant probability to fail at the same time. When path protection is employed, we require the primary path and the backup path to be duct-disjoint, so that the network is survivable under single-duct failures. Moreover, if two primary paths go through any common duct, their backup paths cannot share wavelengths on common links. This study addresses the routing and wavelength-assignment problem in a network with path protection under duct-layer constraints. Off-line algorithms for static traffic is developed to combat single-duct failures. The objective is to minimize total number of wavelengths used on all the links in the network. Both integer linear programs and a heuristic algorithm are presented and their performance is compared through numerical examples.
Option Pricing with a General Marked Point Process
Authors: Jean-Luc Prigent
Venue: Mathematics of Operations Research (2001)

This paper examines the impact of a random number of price changes on the options valuation. The model introduces the structure of the general marked point processes (MPP). This kind of model allows us to take account of more general distributions of interarrival times than usual jump-diffusion models. In particular, stock price variations can be correlated with the times of transactions. Thus, the investors can decide to trade according to the history of market values and the sizes of price variations can also depend on the past times of transactions. By using the special decomposition of predictable processes, with respect to a marked point process, the determination of all risk-neutral probabilities is detailed. Derivative prices are calculated in this context with different basic examples.
Data Envelopment Analysis and its Use in Banking
Authors: M. S. Krishnan, Venkatram Ramaswamy, Mary C. Meyer, Paul Damien, Emmanuel Thanassoulis
Venue: Interfaces (1999)

Data envelopment analysis (DEA) is a linear-programming-based method for assessing the performance of homogeneous organizational units and is increasingly being used in banking. The unit of assessment is normally the bank branch. Studies are mostly centered on deriving a summary measure of the efficiency of each unit, on estimating targets of performance for the unit, and on identifying role-model units of good operating practice. Additional uses for DEA in banking include the measurement of efficiency in light of resource and output prices, the estimation of operating budgets that are conducive to efficiency, the assessment of financial risk at bank-branch level, and the measurement of the impact of managerial change initiatives on productivity.
New technologies and institutional change in public administration
Authors: Mila Gascó
Venue: Social Science Computer Review (2003)

This article aims to study and analyze, from a multidisciplinary point of view, the organizational and institutional transformations that public administration is experiencing due to a country's transition to the information and knowledge society. Three specific goals are pursued: (a) studying the use of new technologies in the public administration, (b) studying the impact brought about by the use of new technologies by the public administration, and (c) studying the institutional changes caused by the use of these technologies. To achieve these goals, three guiding lines are considered: first, the term governance; that is, the collection of institutions and rules that set the limits and the incentives needed for the constitution and functioning of interdependent networks of actors (government, private sector and civil society actors); second, the new institutionalism perspective; and finally, the relationship between technology and organizational and institutional change.