ppxscal/embedding_network huggingface dataset:
Adjustable robust solutions of uncertain linear programs
Authors: A. Ben-Tal, A. Goryashko, E. Guslitzer, A. Nemirovski
Venue: Mathematical Programming: Series A and B (2004)

We consider linear programs with uncertain parameters, lying in some prescribed uncertainty set, where part of the variables must be determined before the realization of the uncertain parameters (&#x2018;&#x2018;non-adjustable variables&#x2019;&#x2019;), while the other part are variables that can be chosen after the realization (&#x2018;&#x2018;adjustable variables&#x2019;&#x2019;). We extend the Robust Optimization methodology ([1, 3-6, 9, 13, 14]) to this situation by introducing the Adjustable Robust Counterpart (ARC) associated with an LP of the above structure. Often the ARC is significantly less conservative than the usual Robust Counterpart (RC), however, in most cases the ARC is computationally intractable (NP-hard). This difficulty is addressed by restricting the adjustable variables to be affine functions of the uncertain data. The ensuing Affinely Adjustable Robust Counterpart (AARC) problem is then shown to be, in certain important cases, equivalent to a tractable optimization problem (typically an LP or a Semidefinite problem), and in other cases, having a tight approximation which is tractable. The AARC approach is illustrated by applying it to a multi-stage inventory management problem.
The Number of Isosceles Right Triangles Determined by n Points in Convex Position in the Plane
Authors: Changqing Xu, Ren Ding
Venue: Discrete Computational Geometry (2004)

Any set of n points in convex position in the plane induces at most 2n congruent copies of a fixed isosceles triangle. Furthermore, at most 2n&#x2013;4 congruent isosceles right triangles can be induced by a set of n points in convex position, and in strictly convex position at most n congruent isosceles right triangles can be induced.
Organizational Management in Workflow Applications &ndash; Issues and Perspectives
Authors: Michael Zur Muehlen
Venue: Information Technology and Management (2004)

Business processes automation requires the specification of process structures as well as the definition of resources involved in the execution of these processes. While the modeling of business processes and workflows is well researched, the link between the organizational elements and process activities is less well understood, and current developments in the web services choreography area completely neglect the organizational aspect of workflow applications. The purpose of this paper is to give an overview of the organizational aspects of workflow technology in the context of the workflow life cycle, to provide a review of existing work, and to develop guidelines for the design of a workflow-enabled organization, which can be used by both workflow vendors and users.
A Review on Level of Detail
Authors: Tan Kim Heok, Daut Daman
Venue: Proceedings of the International Conference on Computer Graphics, Imaging and Visualization (2004)

Recent advances in modern 3D scanning technology and the increasingly size of computer simulations have led to a rapid increase in the availability and size of geometry data sets. Gigantic polygonal data sets, consisting of hundreds of millions of faces, are becoming quite common. While the performance of graphics hardware also seen a drastic rise in these years, however, ability to produce enormous data sets overload the capabilities of the state-of-the-art graphics chip. Therefore, automatic model simplification and run-time level of detail (LOD) management techniques are introduced. In this paper, we present a review on level of detail techniques in an organized structure. Level of detail framework, level of detail management, level of detail simplification models and metrics for simplification and error evaluation are discussed in sequence. Finally, some current issues and conclusion will be given.
Toward excitation and inhibition in neutrosophic logic: a multiagent model based on ying-yang philosophy
Authors: Feng Liu
Venue: Smarandache Notions Journal (2004)

Logic should have been defined as the unity of contradiction between logic director and logic implementation. Chinese Daoism asserts that everything is defined in the unity of opposites, namely yin and yang, accordingly yang conducts change and yin brings it up (I-Ching, also known as Book of Changes). In this way logic is redefined in an indeterminate style to facilitate "both A and Anti-A" etc. in neutrosophics of logic. The unity of opposites is also described as neutrality in neutrosophy. An intermediate multi-referential model of excitation and inhibition is developed to derive a multiagent architecture of logic, based on Chinese yin-yang philosophy. This methodology of excitation/inhibition suggests a rhymed way of logic, leading to a dynamic methodology of weight strategy that links logic with neural network approach. It also confirms the crucial role of indeterminacy in logic as a fatal criticism to classical mathematics and current basis of science.
Scripting High Performance Earth Systems Simulations on the SGI Altix 3700
Authors: Matt Davies, Lutz Gross, Hans Muhlhaus
Venue: Proceedings of the High Performance Computing and Grid in Asia Pacific Region, Seventh International Conference (2004)

A Python language scripting interface for optimised numerical software written in C/C++ has been designed to facilitate the rapid development of 3D parallel simulations on the Altix 3700. A recent advance focusing on the extensions implemented within a high performance finite element kernel module is described. Performance issues, measurements and results on the Altix 3700 are presented.
Sharp Bounds for Vertical Decompositions of Linear Arrangements in Four Dimensions
Authors: Vladlen Koltun
Venue: Discrete Computational Geometry (2004)

We prove tight and near-tight combinatorial complexity bounds for vertical decompositions of arrangements of hyperplanes and 3-simplices in four dimensions. In particular, we prove a tight upper bound of &#x0398;(n4) for the vertical decomposition of an arrangement of n hyperplanes in four dimensions, improving the best previously known bound [8] by a logarithmic factor. We also show that the complexity of the vertical decomposition of an arrangement of n 3-simplices in four dimensions is O(n4 &#x03b1; (n) log2 n), where &#x03b1; (n) is the inverse Ackermann function, improving the best previously known bound [2] by a near-linear factor.
Subspace clustering for high dimensional data: a review
Authors: Lance Parsons, Ehtesham Haque, Huan Liu
Venue: ACM SIGKDD Explorations Newsletter (2004)

Subspace clustering is an extension of traditional clustering that seeks to find clusters in different subspaces within a dataset. Often in high dimensional data, many dimensions are irrelevant and can mask existing clusters in noisy data. Feature selection removes irrelevant and redundant dimensions by analyzing the entire dataset. Subspace clustering algorithms localize the search for relevant dimensions allowing them to find clusters that exist in multiple, possibly overlapping subspaces. There are two major branches of subspace clustering based on their search strategy. Top-down algorithms find an initial clustering in the full set of dimensions and evaluate the subspaces of each cluster, iteratively improving the results. Bottom-up approaches find dense regions in low dimensional spaces and combine them to form clusters. This paper presents a survey of the various subspace clustering algorithms along with a hierarchy organizing the algorithms by their defining characteristics. We then compare the two main approaches to subspace clustering using empirical scalability and accuracy tests and discuss some potential applications where subspace clustering could be particularly useful.
Applying Two-Level Simulated Annealing on Bayesian Structure Learning to Infer Genetic Networks
Authors: Tie Wang, Jeffrey W. Touchman, Guoliang Xue
Venue: Proceedings of the 2004 IEEE Computational Systems Bioinformatics Conference (2004)

Bayesian network is a common approach to study gene regulatory networks. Here, we explore the problem of inferring Bayesian structure from data that can be viewed as a search problem. The goal is to find a global optimized probability network model given the data. In this work, we propose a new search algorithm: Two-level Simulated Annealing (TLSA). TLSA performs simulated annealing in two levels with strengthened local optimizer, and is less likely to get tracked at local optimizer. To illustrate the value of TLSA in Bayesian structure learning, the algorithms is applied on simulated datasets generated using the Monte Carlo method. The experimental results are compared with other learning algorithm such as K2.
Reuse in Reverse Engineering
Venue: Proceedings of the 12th IEEE International Workshop on Program Comprehension (2004)

In this paper, we present a framework for reverse engineeringallowing the integration and interaction of differentanalysis and visualization tools. The framework architecturethat we propose uses a dynamic type system to guaranteethe proper exchange of data between the tools and aset of wrapper classes to handle their communication. Thisallows for an easy and secure integration of tools that haveoriginally not been designed to work together. In this sense,existing tools can be (re-)used and integrated. As a proofof concept we also present our own instantiation of the proposedframework architecture.
Relationships Among Flag f-Vector Inequalities for Polytopes
Authors: Catherine Stenson
Venue: Discrete Computational Geometry (2004)

We examine linear inequalities satisfied by the flag $f$-vectors of polytopes. One source of these inequalities is the toric $g$-vector; convolutions of its entries are non-negative for rational polytopes. We prove a conjecture of Meisinger about a redundancy in these inequalities. Another source of inequalities is the {\bf cd}-index; among all $d$-polytopes, each {\bf cd}-index coefficient is minimized on the $d$-simplex. We show that not all of the {\bf cd}-index inequalities are implied by the toric $g$-vector inequalities, and that not all of the toric $g$-vector inequalities are implied by the {\bf cd}-index inequalities. Finally, we show that some inequalities from convolutions of {\bf cd}-index coefficients are implied by other {\bf cd}-index inequalities. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Modeling and Language Support for the Management of Pattern-Bases
Authors: Manolis Terrovitis, Panos Vassiliadis, Spiros Skiadopoulos, Elisa Bertino, Barbara Catania, Anna Maddalena
Venue: Proceedings of the 16th International Conference on Scientific and Statistical Database Management (2004)

In our days knowledge extraction methods are able toproduce artifacts (also called patterns) that concisely represent data. Patterns are usually quite heterogeneous andrequire ad-hoc processing techniques. So far, little emphasis has been posed on developing an overall integrated environment for uniformly representing and querying different types of patterns. Within the larger context of modelling, storing, and querying patterns, in this paper, we: (a) formally define the logical foundations for the globalsetting of pattern management through a model that covers data, patterns and their intermediate mappings; (b) present a pattern specification language for pattern management along with safety restrictions; and (c) introduce queries and query operators and identify interesting query classes.
Proof of functional Smarandache iterations
Authors: Zheng Jianfeng
Venue: Smarandache Notions Journal (2004)

The paper makes use of method of Mathematics Analytic to prove Functional Smarandache Iterations of three kinds.
Efficient Hardware Voxelization
Authors: G. Passalis, I. A. Kakadiaris, T. Theoharis
Venue: Proceedings of the Computer Graphics International (2004)

This paper presentes a novel algorithm for the voxelizationof surface models of arbitrary topology. Our algorithmuses the depth and stencil buffers, available in most commercialgraphics hardware, to achieve high performance. Itis suitable for both polygonal meshes and parametric surfaces.Experiments highlight the advantages and limitationsof our approach.
Small BV Solutions of Hyperbolic Noncooperative Differential Games
Authors: Alberto Bressan, Wen Shen
Venue: SIAM Journal on Control and Optimization (2004)

The paper is concerned with an n-person differential game in one space dimension. We state conditions for which the system of Hamilton--Jacobi equations for the value functions is strictly hyperbolic. In the positive case, we show that the weak solution of a corresponding system of conservation laws determines an n-tuple of feedback strategies. These yield a Nash equilibrium solution to the noncooperative differential game.
Automatic Generation of a Simulation Compiler by a HW/SW Co-Design System
Authors: Hideaki Yanagisawa, Minoru Uehara, Hideki Mori
Venue: Proceedings of the 15th IEEE International Workshop on Rapid System Prototyping (2004)

An ISA (Instruction Set Architecture) simulator is anindispensable tool for the design, development andcustomization of new processors. ISA simulators providevarious features such as checking instruction behaviorand/or estimating performance and chip size fora target processor. Due to the increasing complexity ofchip architecture and time to market pressure, performancebecomes one of the most important featuresfor ISA simulators. This paper describes a techniquefor automatic generation of a simulation compiler thattranslates a target code into a host code, by a HW/SWcodesign system. We proposed an indirect approach forthe simulation compiler; whereby, an execution file ofa target processor is modeled in the C language andtranslated into the execution file of the host machineusing a compiler. An advantage of our approach is theability of the compiler on the host machine to easilytranslate a target code into host codes.
Distributed Control of Multi-Robot Systems Engaged in Tightly Coupled Tasks
Authors: Terry L. Huntsberger, Ashitey Trebi-Ollennu, Hrand Aghazarian, Paul S. Schenker, Paolo Pirjanian, Hari Das Nayar
Venue: Autonomous Robots (2004)

NASA mission concepts for the upcoming decades of this century include exploration of sites such as steep cliff faces on Mars, as well as infrastructure deployment for a sustained robotic/manned presence on planetary and/or the lunar surface. Single robotic platforms, such as the Sojourner rover successfully flown in 1997 and the Mars Exploration Rovers (MER) which landed on Mars in January of 2004, have neither the autonomy, mobility, nor manipulation capabilities for such ambitious undertakings. One possible approach to these future missions is the fielding of cooperative multi-robot systems that have the required onboard control algorithms to more or less autonomously perform tightly coordinated tasks. These control algorithms must operate under the constrained mass, volume, processing, and communication conditions that are present on NASA planetary surface rover systems. In this paper, we describe the design and implementation of distributed control algorithms that build on our earlier development of an enabling architecture called CAMPOUT (Control Architecture for Multi-robot Planetary Outposts). We also report on some ongoing physical experiments in tightly coupled distributed control at the Jet Propulsion Lab in Pasadena, CA where in the first study two rovers acquire and carry an extended payload over uneven, natural terrain, and in the second three rovers form a team for cliff access.
An exploratory study into whether to or not to include users in the development of industrial hypermedia applications
Authors: Devendra Fakun, M. Greenough
Venue: Requirements Engineering (2004)

While there is agreement among both information system (IS) practitioners and IS researchers as to the value of user participation in IS development, the correlation between user participation and actual use or user satisfaction (surrogate measures of IS success) has been equivocal. A possible reason for the contradictory findings could be that user participation is being utilised, regardless of the levels of complexity of either the system or the task. This paper describes two exploratory case studies to test this hypothesis. Industrial hypermedia applications (IHA) were developed and qualitative data collected, through usability trials, to see the effect of user participation on user perception (extrinsic motivations of use) of the system, rather than IS success. The findings show that users should participate in the development when both the IS and the task are complex. On the other hand, when both the system and the task are not complex, user participation can be kept to a minimum. Furthermore, it is recommended that user participation should not be evaluated against IS success, but against system features.
Varieties generated by T-norms
Authors: M. Gehrke, C. Walker, E. Walker
Venue: Soft Computing - A Fusion of Foundations, Methodologies and Applications (2004)

This is a survey of some work done recently on varieties generated by algebras arising in fuzzy set theory and logic. Details and proofs appear elsewhere. The hope is to impart some of the flavor of this particular topic, and to point out some areas that merit further study.
An associative classifier based on positive and negative rules
Authors: Maria-Luiza Antonie, Osmar R. Zaïane
Venue: Proceedings of the 9th ACM SIGMOD workshop on Research issues in data mining and knowledge discovery (2004)

Associative classifiers use association rules to associate attribute values with observed class labels. This model has been recently introduced in the literature and shows good promise. The proposals so far have only concentrated on, and differ only in the way rules are ranked and selected in the model. We propose a new framework that uses different types of association rules, positive and negative. Negative association rules of interest are rules that either associate negations of attribute values to classes or negatively associate attribute values to classes. In this paper we propose a new algorithm to discover at the same time positive and negative association rules. We introduce a new associative classifier that takes advantage of these two types of rules. Moreover, we present a new way to prune irrelevant classification rules using a correlation coefficient without jeopardizing the accuracy of our associative classifier model. Our preliminary results with UCI datasets are very encouraging.
Failure Data Analysis of a Large-Scale Heterogeneous Server Environment
Authors: Ramendra K. Sahoo, Anand Sivasubramaniam, Mark S. Squillante, Yanyong Zhang
Venue: Proceedings of the 2004 International Conference on Dependable Systems and Networks (2004)

The growing complexity of hardware and software mandatesthe recognition of fault occurrence in system deploymentand management. While there are several techniquesto prevent and/or handle faults, there continues to be agrowing need for an in-depth understanding of system errorsand failures and their empirical and statistical properties.This understanding can help evaluate the effectivenessof different techniques for improving system availability, inaddition to developing new solutions. In this paper, we analyzethe empirical and statistical properties of system errorsand failures from a network of nearly 400 heterogeneousservers running a diverse workload over a year. While improvementsin system robustness continue to limit the numberof actual failures to a very small fraction of the recordederrors, the failure rates are significant and highly variable.Our results also show that the system error and failure patternsare comprised of time-varying behavior containinglong stationary intervals. These stationary intervals exhibitvarious strong correlation structures and periodic patterns,which impact performance but also can be exploited to addresssuch performance issues.
On scaling latent semantic indexing for large peer-to-peer systems
Authors: Chunqiang Tang, Sandhya Dwarkadas, Zhichen Xu
Venue: Proceedings of the 27th annual international ACM SIGIR conference on Research and development in information retrieval (2004)

The exponential growth of data demands scalable infrastructures capable of indexing and searching rich content such as text, music, and images. A promising direction is to combine information re-trieval with peer-to-peer technology for scalability, fault-tolerance, and low administration cost. One pioneering work along this di-rection is pSearch [32, 33]. pSearch places documents onto a peer-to- peer overlay network according to semantic vectors produced using Latent Semantic Indexing (LSI). The search cost for a query is reduced since documents related to the query are likely to be co-located on a small number of nodes. Unfortunately, because of its reliance on LSI, pSearch also inherits the limitations of LSI. (1) When the corpus is large and heterogeneous, LSI's retrieval quality is inferior to methods such as Okapi. (2) The Singular Value Decomposition (SVD) used in LSI is unscalable in terms of both memory consumption and computation time.This paper addresses the above limitations of LSI and makes the following contributions. (1) To reduce the cost of SVD, we reduce the size of its input matrix through document clustering and term selection. Our method retains the retrieval quality of LSI but is several orders of magnitude more efficient. (2) Through extensive experimentation, we found that proper normalization of semantic vectors for terms and documents improves recall by 76%. (3) To further improve retrieval quality, we use low-dimensional subvectors of semantic vectors to cluster documents in the overlay and then use Okapi to guide the search and document selection.
Hands-Free Navigation Methods for Moving through a Virtual Landscape Walking Interface Virtual Reality Input Devices
Authors: Salvador Barrera, Hiroki Takahashi, Masayuki Nakajima
Venue: Proceedings of the Computer Graphics International (2004)

Technological limitations on current interfaces havemade researches to develop new devices to interact with objectsin the virtual environment. The goal of this project isto develop and build a hands-free navigation system to beintegrated into virtual environments. One of the most importantfields in virtual realty (VR) research, is the developmentof systems that allow the user to interface with thevirtual environment. The most intuitive method for movingthrough a virtual landscape is by walking. The implementationof a walking interface for a virtual reality system alsoallows a greater range of biomechanical experimentationand game research. Systems ranging from different platformshave already been implemented to produce virtualwalking; however, these systems have been designed primarilyfor use with head mounted display systems. We believethat hands-free navigation, unlike the majority of navigationtechniques based on hand motions, has the greatestpotential for maximizing the interactivity of virtual environments,due to more direct motion of the feet. To make thispossible, we created a new and simple device using accelerationsensors to detect ankle movements within the virtualenvironment. The acceleration sensors are attached tothe foot and detect movement based on direction for threedifferent angles. This experimentation could prove beneficial in future virtual gaming. Validation of our approach is given by discussion and illustration of some results.