ppxscal/embedding_network huggingface dataset:
A global optimization heuristic for estimating agent based models
Authors: M. Gilli, P. Winker
Venue: Computational Statistics Data Analysis (2003)

A continuous global optimization heuristic for a stochastic approximation of an objective function, which itself is not globally convex, is introduced. The objective function arises from the simulation based indirect estimation of the parameters of agent based models of financial markets. The function is continuous in the variables but non-differentiable. Due to Monte Carlo variance, only a stochastic approximation of the objective function is available. The algorithm combines features of the Nelder-Mead simplex algorithm with those of a local search heuristic called threshold accepting. The Monte Carlo variance of the simulation procedure is also explicitly taken into account. We present details of the algorithm and some results of the estimation of the parameters for a specific agent based model of the DM/US-$ foreign exchange market.
Commentary: the World Wide Web: It'S the Customers
Authors: Michael Trick
Venue: INFORMS Journal on Computing (1998)

The feature article by Bhargava and Krishnan does a wonderful job of outlining the current state of the Web and its future possibilities. The Web is an active and ever-changing place; providing a snapshot of the state of the art is not easy. In this commentary, I would like to concentrate on a group that the article does not cover in depth: the users of OR/MS. The number of users of OR/MS is vastly larger than the producers of OR/MS, and has been affected perhaps even more by the Web. I will concentrate on two types of users: those who do not know what OR/MS is but have found our community through the Web, and our students.
Classification of association schemes of small order
Authors: A. Hanaki, I. Miyamoto
Venue: Discrete Mathematics (2003)

This paper enumerates the isomorphism classes of association schemes of order 20-28 by using the computer. It also classifies all the association schemes of order 24-28 whether their automorphism groups are transitive or not, and whether they are group case or not. Some more properties of the obtained association schemes are computed.
Metrics for structural logic synthesis
Authors: Prabhakar Kudva, Andrew Sullivan, William Dougherty
Venue: Proceedings of the 2002 IEEE/ACM international conference on Computer-aided design (2002)

Routability or wiring congestion in a VLSI chip is becoming increasingly important as chip complexity increases. Congestion has a significant impact on performance, yield and chip area. Although advances in placement algorithms have attempted to alleviate this problem, the inherent structure of the logic netlist has a significant impact on the routability irrespective of the placement algorithm used. Placement algorithms find optimal assignment of locations to the logic and do not have the ability to change the netlist structure. Significant decisions regarding the circuit structure are made early in synthesis such as during the technology independent logic optimization step. Optimizations in this step use literal count as a metric for optimization and do not adequately capture the intrinsic entanglement of the netlist. Two circuits with identical literal counts may have significantly different congestion characteristics post placement. In this paper, we motivate that a property of the network structure called adhesion can make a significant contribution to routing congestion. We then provide a metric to measure this property. We also show that adhesion as measured by this metric can be used in addition to literal counts to estimate and optimize post routing congestion early in the design flow.
A conversation with Ruby Lee
Authors: Ubiquity staff
Venue: Ubiquity (2002)

Innovative computer scientist Ruby Lee talks about secure information processing, efficient permutations, fair use in the digital age, and more.
On a conjecture of F. Smarandache
Authors: Wang Yang, Zhang Hong Li
Venue: Smarandache notions (2002)

The main purpose of this paper is to solve a problem generated by Professor F.Smarandache.
A generalization of the E-LOTOS trapping operator: towards reconciliation with LOTOS
Authors: M. Kapus-Kolar
Venue: Computer Standards Interfaces (2002)

LOTOS and its enhanced version E-LOTOS are standard languages for formal specification of concurrent and reactive systems. For better backward compatibility of E-LOTOS with LOTOS, we introduce into E-LOTOS specification and trapping of non-urgent and potentially decisive successful termination of processes.
Combining fuzzy and case-based reasoning to generate human-like music performances
Authors: Josep Lluís Arcos, Ramon López de Mántaras
Venue: Technologies for constructing intelligent systems: Tasks (2002)

In this brief paper we describe several extensions and improvements of a previously reported system [2] capable of generating expressive music by imitating human performances. The system is based on Case-Based Reasoning (CBR) and Fuzzy techniques.
Invariant algebraic curves linear in one variable for planar real quadratic systems
Authors: Javier Chavarriga, Maite Grau
Venue: Applied Mathematics and Computation (2003)

In this paper we study algebraic solutions of the form h(x,y) = p1(x)y + p2(x), where p1(x) and p2(x) are real coprime polynomials and p1(x) ≠ 0, for a planar real algebraic quadratic system. We analyze the existence of this kind of solutions depending on the coefficients of the system.
Putting it all together with Robert Kahn
Authors: Ubiquity staff
Venue: Ubiquity (2003)

The co-founder of the Internet recalls the non-commercial early days and looks at today's issues of fair use, privacy and the need for security.
Perspectives on HCI patterns: concepts and tools
Authors: Sally Fincher, Janet Finlay, Sharon Greene, Lauretta Jones, Paul Matchen, John Thomas, Pedro J. Molina
Venue: CHI '03 extended abstracts on Human factors in computing systems (2003)

This workshop will explore a diversity of perspectives on Patterns and Patterns Languages for HCI as well as the requirements for software tools needed to improve the effectiveness of both pattern creation and pattern use. Through discussion of conceptual and methodological issues of why (and how) patterns are identified and in what circumstances they are useful in the design process we hope to map out the conceptual landscape of HCI patterns. By moving closer and examining pattern-related behavior and experiences we hope to identify the requirements for tools to make progress through that landscape.
SuperPascal: a publication language for parallel scientific computing
Authors: Per Brinch Hansen
Venue: The origin of concurrent programming: from semaphores to remote procedure calls (2002)

Parallel computers will not become widely used until scientists and engineers adopt a common programming language for publication of parallel scientific algorithms. This paper describes the publication language SuperPascal by examples. SuperPascal extends Pascal with deterministic statements for parallel processes and synchronous message communication. The language permits unrestricted combinations of recursive procedures and parallel statements. SuperPascal omits ambiguous and insecure features of Pascal. Restrictions on the use of variables enable a single-pass compiler to check that parallel processes are disjoint, even if the processes use procedures with global variables. A portable implementation of SuperPascal has been developed on a Sun workstation under Unix.
Scheduling Solutions for the Paper Industry
Authors: Pinar Keskinocak, Frederick Wu, Richard Goodwin, Sesh Murthy, Rama Akkiraju, Santhosh Kumaran, Annap Derebail
Venue: Operations Research (2002)

This paper describes a decision support system for paper production scheduling. This is the first system to provide an integrated solution to paper production scheduling and to consider interactions between different stages of the manufacturing and distribution process. Using a multicriteria optimization approach, the system generates multiple enterprisewide schedules to reveal tradeoffs between the multiple, often competing, objectives. The large portfolio of algorithms used by the system is embedded in an agent-based decision support framework, called Asynchronous Team (A-Team). Successful implementations of the system in several paper mills in North America have resulted in significant savings and improved customer satisfaction.
Adaptable QoS management communication architectures for user perception
Authors: G. Ghinea, J. P. Thomas
Venue: Adaptive evolutionary information systems (2003)

Distributed multimedia systems are characterised by a broad spectrum of quality of service (QoS) parameters which must be managed dynamically to ensure an acceptable user experience. Whilst there has been a considerable amount of work on QoS management itself, not the same can be said about the way that variations in QoS impact upon the user multimedia experience. We introduce the term quality of perception (QoP) to characterise the latter and, in this chapter, after a review of QoS-oriented communication architectures and protocols, highlight our experiences of using a specifically tailored adaptive communication protocol to provide an enhanced QoP.
Distributed processing in support of an imaging project
Authors: Brian Culver
Venue: Journal of Computing Sciences in Colleges (2003)

This paper describes the results of a distributed processing system implemented as part of a research project under the guidance of Dr. Peter Cooper, chair of the Department of Computer Science at Sam Houston State University.The project involves the development of a mechanism for delivering "near real-time" 3D, manipulable, medical images to low-end computing systems. The initial implementation is one in which MRI data is processed into a small number of clusters, each representing a specific tissue type and then each cluster being structured as a vector of tiles that can then be transmitted to the client and represented on the screen. The statistical techniques used to cluster the data are beyond the scope of this paper, which is primarily concerned with managing the computing resources.A system for processing a large amount of image data was required that did not involve purchasing high-end equipment. By using distributed computing techniques to distribute the processing of the image data, an economical and readily available resource was provided. Processing the data closer to real-time can be achieved as this system is improved and developed further. From this system, it can be expected to greatly improve the efficiency and reduce the time involved for solving large problems.
On the Matrix-Cut Rank of Polyhedra
Authors: William Cook, Sanjeeb Dash
Venue: Mathematics of Operations Research (2001)

LovÃ¡sz and Schrijver (1991) described a semidefinite operator for generating strong valid inequalities for the 0-1 vectors in a prescribed polyhedron. Among their results, they showed thatn iterations of the operator are sufficient to generate the convex hull of 0-1 vectors contained in a polyhedron inn-space. We give a simple example, having ChvÃ¡tal rank 1, that meets this worst case bound ofn. We describe another example requiringn iterations even when combining the semidefinite and Gomory-ChvÃ¡tal operators. This second example is used to show that the standard linear programming relaxation of ak-city traveling salesman problem requires at least ? k/8? iterations of the combined operator; this bound is best possible, up to a constant factor, ask+1 iterations suffice.
Fast adaptive control of a complex non-linear system by adalines: motion in a fluid under thruster power
Authors: Gilles Labonté
Venue: Second international workshop on Intelligent systems design and application (2002)

We demonstrate that simple adalines can learn to mimic the complex non-linear dynamics of a thruster propelled vehicle that moves in a fluid. This is made possible by our supplying them with judiciously chosen non-linear inputs. We then use such adalines to provide the internal model on which we base an adaptive motion controller for such a vehicle. The latter thus becomes able of intelligent behavior, in that it can predict ahead of time what its dynamical state will be, and can adjust its reactions accordingly. It will also be able to adapt to the incidents that modify its behavior or its environment. We demonstrate that our control system performs flawlessly and, in particular, is able to keep the vehicle perfectly still, without it developing the limit cycle observed in most marine vehicles. The well known ability of adalines to adapt rapidly endows this controller with all the features that can be wished for in a neural network system. It learns by itself, and it learns so rapidly that it can be given the responsibility of the vehicle with adaline weights initialized to zero. The fact that simple adalines suffice for this complex task is important in itself because the technique we describe can straightforwardly be generalized to many other situations.
Finite element methods for pricing American options on stocks
Authors: Walter Allegretto, Yanping Lin, Hongtao Yang
Venue: Scientific computing and applications (2001)

In this paper we extend the finite element method and its error estimate for pricing American options on stocks given in [3] by using general time discrete schemes. Numerical examples are presented to examine convergence rates of the implicit Euler scheme and the Crank-Nicholson scheme.
Order-Fulfillment Performance Measures in An Assemble-To-Order System with Stochastic Leadtimes
Authors: Jing-Sheng Song, Susan H. Xu, Bin Liu
Venue: Operations Research (1999)

We study a multicomponent, multiproduct production and inventory system in which individual components are made to stock but final products are assembled to customer orders. Each component is produced by an independent production facility with finite capacity, and the component inventory is controlled by an independent base-stock policy. For any given base-stock policy, we derive the key performance measures, including the probability of fulfilling a customer order within any specified time window. Computational procedures and numerical examples are also presented. A similar approach applies to the generic multi-item make-to-stock inventory systems in which a typical customer order consists of a kit of items.
Instabilities of Strategic Alliances: An Internal Tensions Perspective
Authors: T. K. Das, Bing-Sheng Teng
Venue: Organization Science (2000)

The instabilities of strategic alliances have been examined in the literature through a number of theoretical approaches. Alliance instabilities refer to major changes or dissolutions of alliances that are unplanned from the perspective of one or more partners. Although the literature identifies certain characteristics of strategic alliances that may lead to their unplanned dissolution, the extent of our understanding of this subject appears to be fragmented and incomplete. In this article we propose a comprehensive framework for adequately understanding alliance instabilities based on the notion of internal tensions. We suggest that strategic alliances are sites in which conflicting forces develop and which can be viewed as being constituted by three key pairs of competing forces--namely, cooperation versus competition, rigidity versus flexibility, and short-term versus long-term orientation. This tensions framework helps us in explaining the intrinsic vulnerability of alliances in terms of a wide range of internal contradictions and enables us to examine, in an integrated manner, the incidence, dynamics, and eventual dissipation of the inherent instabilities. We discuss the interrelationships among the different internal tensions and their impacts on different types of strategic alliances. We also examine the termination of alliances through mergers/acquisitions and dissolution. Finally, we suggest ways to empirically test the various ideas and propositions developed here and indicate directions for further research.
Exploring importance of location and prior knowledge of environment on mobile robot control
Authors: Ali Şafak Sekmen, Mitch Wilkes, Susan R. Goldman, Saleh Zein-Sabatto
Venue: International Journal of Human-Computer Studies (2003)

Advances in technologies to create ever more sophisticated robots is outpacing our understanding of how such robots and humans successfully interact to accomplish specific tasks. In particular, it is now possible for humans to control the navigation of certain classes of robots via the Internet. Yet, we know little about how individual differences variables such as spatial ability and prior knowledge of the navigational space contribute to the success of human-robot interactions. Nor has there been much research on the kinds of interfaces that facilitate effective and efficient interaction, and whether these are differentially effective across the spectrum of spatial ability. In this study, an Internet control mechanism for an RWI B-14 mobile robot called "TourMate" was used to investigate the differences and similarities in how humans teleoperated the robot from two locations (intermediate and remote). Thirty-two participants who were assessed on spatial albility and prior knowledge of the space in which the robot was being controlled directed the robot in simple spatial navigation tasks. Time to comptete the task, number of steps, and errors were collected. Results indicated that spatial ability and location, but not prior knowledge, were reliable predictor of efficiency of robot teleoperation. Information was also obtained about the utility of various features of the interface and suggested that individual difference characteristics of robot operators are related to the utility of different interface features. Implications for design of human-robot interaction systems are discussed.
Drawing K2,n: a lower bound
Authors: Therese Biedl, Timothy M. Chan, Alejandro López-Ortiz
Venue: Information Processing Letters (2003)

We give a tradeoff theorem between the area and the aspect ratio required by any planar straight-line drawing of K2,n on the integer lattice. In particular we show that if the drawing is contained in a rectangle of area O(n) then the rectangle must have aspect ratio Ω (n), and conversely, if the aspect ratio is O(1) then the area must be Ω (n2/log2/n).
Language integration in the common language runtime
Authors: Jennifer Hamilton
Venue: ACM SIGPLAN Notices (2003)

The Common Language Runtime (CLR) is language and platform-neutral, and provides the underlying infrastructure for the Microsoft .NET Framework. A key innovation in the CLR is its support for multiple programming languages, enabling programming language integration at the runtime level to a much greater degree than is currently possible.
Electromagnetic Noise Superimposed on the Electric Power Supply to Electronic Medical Equipment
Authors: Eisuke Hanada, Kyoko Takano, Kenji Kodama
Venue: Journal of Medical Systems (2003)

The use of mobile medical electronic equipment driven at low electric power outputs has progressed rapidly in recent years. Voltage change and noise superimposed on the power supply could create obstacles to the operation of medical electronic equipment. We observed the quality of the power supply of medical electronic equipment in a university hospital, and found approximately 5% distortion on voltage. Possible causes of the distortion and factors involved in voltage/current distortion are discussed. Also shown are some points for avoiding power supply problems when using medical electronic equipment.
A geometric theory for preconditioned inverse iteration applied to a subspace
Authors: Klaus Neymeyr
Venue: Mathematics of Computation (2002)

The aim of this paper is to provide a convergence analysis for a preconditioned subspace iteration, which is designated to determine a modest number of the smallest eigenvalues and its corresponding invariant subspace of eigenvectors of a large, symmetric positive definite matrix. The algorithm is built upon a subspace implementation of preconditioned inverse iteration. i.e., the well-known inverse iteration procedure, where the associated system of linear equations is solved approximately by using a preconditioner. This step is followed by a Rayleigh-Ritz projection so that preconditioned inverse iteration is always applied to the Ritz vectors of the actual subspace of approximate eigenvectors. The given theory provides sharp convergence estimates for the Ritz values and is mainly built on arguments exploiting the geometry underlying preconditioned inverse iteration.
Using attributed plex grammars for the generation of image and graph databases
Authors: Markus Hagenbuchner, Marco Gori, Horst Bunke, Ah Chung Tsoi, Christophe Irniger
Venue: Pattern Recognition Letters (2003)

In this paper, a methodology for the generation of benchmarks in pattern recognition is described. The patterns are represented by means of an attributed plex language, which are based on plex grammars augmented by attributes. It is shown that the generated patterns are particularly suitable for the extraction of graph-based representations. As a result, databases of artificial pictures and correspondent graphs can be generated. These collections of graphs are very appropriate for benchmarks in the area of structural pattern recognition, since they are originated from a grammar and not from random distributions. The tools for creating the databases are public domain and have been already used for benchmarking artificial neural networks operating on structured domains.
The Stochastic Inventory Routing Problem with Direct Deliveries
Authors: Anton J. Kleywegt, Vijay S. Nori, Martin W. P. Savelsbergh
Venue: Transportation Science (2002)

Vendor managed inventory replenishment is a business practice in which vendors monitor their customers' inventories, and decide when and how much inventory should be replenished. The inventory routing problem addresses the coordination of inventory management and transportation. The ability to solve the inventory routing problem contributes to the realization of the potential savings in inventory and transportation costs brought about by vendor managed inventory replenishment. The inventory routing problem is hard, especially if a large number of customers is involved. We formulate the inventory routing problem as a Markov decision process, and we propose approximation methods to find good solutions with reasonable computational effort. Computational results are presented for the inventory routing problem with direct deliveries.