ppxscal/embedding_network huggingface dataset:
Coupling multibody dynamics and computational fluid dynamics on 8192 processor cores
Authors: J. Götz, K. Iglberger, C. Feichtinger, S. Donath, U. Rüde
Venue: Parallel Computing (2010)

This paper describes a method for the fully resolved simulation of particle laden flows. For this purpose, we discuss the parallelization of large scale coupled fluid structure interaction with up to 37 million geometrically modeled moving objects incorporated in the flow. The simulation is performed using a 3D lattice Boltzmann solver for the fluid flow and a so-called rigid body physics engine for the treatment of the objects. The numerical algorithms and the parallelization are discussed in detail. Furthermore, performance results are presented for test cases on up to 8192 processor cores running on an SGI Altix supercomputer. The approach enables a detailed simulation of large scale particulate flows that are relevant for many industrial applications.
Harmonic solutions of a mixed boundary problem arising in the modeling of macromolecular transport into vessel walls
Authors: Igor Balsim, Mathew A. Neimark, David S. Rumschitzki
Venue: Computers Mathematics with Applications (2010)

The earliest events leading to atherosclerosis involve the transport of lpw density lipooprotein (LDL) cholesterol from the blood across endothelial cells that line the artery wall. Laplace's equation describes the steady state diffusion profile of a tracer through the vessel wall. This gives rise to a boundary value problem with mixed Dirichlet and Robin conditions. We construct a linear system of integral equations that approximate the coefficients of the series expansion of the solution. We prove the existence of the solution to this problem analytically by using Gershgorin's theorem on the location of the eigenvalues of the corresponding matrix. We give a uniqueness proof using Miranda's theorem [C. Miranda, P.D.E. of Elliptic Type, Springer-Verlag, Berlin, 1970]. The analytical construction method forms the basis for a numerical calculation algorithm. We apply our results to the transport problem above, and use them to interpret experimental observations of the growth of localized tracer leakage spots with tracer circulation time.
Enterprise modeling in a service oriented architecture
Authors: Peter Bollen
Venue: Proceedings of the International Workshop on Enterprises & Organizational Modeling and Simulation (2009)

Service-oriented computing (SOC) is a new paradigm that allows organizations to tailor their business processes, in such a way that efficiency and effectiveness goals will be achieved by outsourcing (parts of) business processes to web-based service-providers. In order to find the computing service-providers that provide the organizations with the biggest benefits, it is paramount that the service-requesting organization (SRO) has a precise description of the service it wants to have delivered by the service delivering organization (SDO). In this paper we will illustrate how enterprises that play the SDO and SRO roles can be conceptually integrated by creating conceptual models that share the definitions of the business processes within the service oriented architecture (SOA) framework.
Analysis and design of a multi-agent system for simulating a crisis response organization
Authors: Rafael A. Gonzalez
Venue: Proceedings of the International Workshop on Enterprises & Organizational Modeling and Simulation (2009)

Simulation is a way to deal with the lack of data and difficulty in designing controlled experiments in the field of crisis response. This paper presents the analysis and design of a simulation model used to evaluate different coordination mechanisms for a crisis response organization. Such organizations are often multidisciplinary, short-lived and ad hoc. Coordination between the responders can be achieved in a structured way (through standards and hierarchy) or can manifest itself in an adaptive or emergent manner. The characteristics of the response organization and the study of structured vs. emergent coordination fit with the capabilities and nature of multi-agent systems (MAS). The MAS model is built using the GAIA methodology and the JADE agent framework. The model can be configured differently to deal with an emergency scenario developed separately as a discrete-event simulation, providing a testbed for simulating coordination in crisis response.
Calibrating embedded protocols on asynchronous systems
Authors: Yukiko Yamauchi, Doina Bein, Toshimitsu Masuzawa, Linda Morales, I. Hal Sudborough
Venue: Information Sciences: an International Journal (2010)

Embedding is a method of projecting one topology into another. In one-to-one node embedding, paths in the target topology correspond to links in the original topology. A protocol running on the original topology can be modified to be executed on a target topology by means of embedding. However, if the protocol is tolerant to a number of faults - faults that affect the data but not the code of a distributed protocol executed by the nodes in a distributed systems - then the adapted protocol will not have the fault tolerance property preserved, due to the fact that links in the original topology can be embedded into paths of length greater than one: faults at the intermediate nodes on such paths are not accounted for in the protocol. We propose a communication protocol in the target topology that preserves the fault tolerance characteristics of any protocol designed for the original topology, namely by our mechanism the modification preserves fault tolerance.
Attitudes of sixth form female students toward the IT field
Authors: Katja Leiviskä, Mikko Siponen
Venue: ACM SIGCAS Computers and Society (2010)

It is well known that girls are not interested in computer science, information systems (IS), and software engineering studies. While the underlying reasons for this phenomenon have been studied in the US, Canada, and Australia, only a few studies have been carried out in Europe and in Scandinavia. To fill this gap in the research, we have analyzed the qualitative responses of 64 female sixth form students concerning their attitudes towards studying information technology (IT), including computer science, information systems, and software engineering disciplines, and their views about IT as a profession. The results suggest that the IT field is seen in quite a positive light by the girls. Although many of the respondents do not consider IT to be their profession, they nevertheless have positive attitudes towards the field. According to the respondents, the field is growing and developing; it is respected, and seen as the field of the future. Girls who want to become IT professionals see that the profession entails good employment possibilities and benefits and is respected. Some girls have negative views towards the field. These views illustrate the underlying reasons why these girls do not want to study IT. The girls did not perceive the field to be human-related (the work is only computer-related, according to the respondents). The need for skills in mathematics and physics are also listed as key reasons why some girls do not want to become IT students. The results of the study suggest that there is a need to clarify among sixth form students the fact that IT jobs can be divided into computer science, information systems, and software engineering, all of which require different competences.
Comparison of Legendre polynomial approximation and variational iteration method for the solutions of general linear Fredholm integro-differential equations
Authors: Necdet Bildik, Ali Konuralp, Salih Yalçınbaş
Venue: Computers Mathematics with Applications (2010)

In this study it is shown that the numerical solutions of linear Fredholm integro-differential equations obtained by using Legendre polynomials can also be found by using the variational iteration method. Furthermore the numerical solutions of the given problems which are solved by the variational iteration method obviously converge rapidly to exact solutions better than the Legendre polynomial technique. Additionally, although the powerful effect of the applied processes in Legendre polynomial approach arises in the situations where the initial approximation value is unknown, it is shown by the examples that the variational iteration method produces more certain solutions where the first initial function approximation value is estimated. In this paper, the Legendre polynomial approximation (LPA) and the variational iteration method (VIM) are implemented to obtain the solutions of the linear Fredholm integro-differential equations and the numerical solutions with respect to these methods are compared.
An evolutionary approach with diversity guarantee and well-informed grouping recombination for graph coloring
Authors: Daniel Cosmin Porumbel, Jin-Kao Hao, Pascale Kuntz
Venue: Computers and Operations Research (2010)

We present a diversity-oriented hybrid evolutionary approach for the graph coloring problem. This approach is based on both generally applicable strategies and specifically tailored techniques. Particular attention is paid to ensuring population diversity by carefully controlling spacing among individuals. Using a distance measure between potential solutions, the general population management strategy decides whether an offspring should be accepted in the population, which individual needs to be replaced and when mutation is applied. Furthermore, we introduce a special grouping-based multi-parent crossover operator which relies on several relevant features to identify meaningful building blocks for offspring construction. The proposed approach can be generally characterized as ''well-informed'', in the sense that the design of each component is based on the most pertinent information which is identified by both experimental observation and careful analysis of the given problem. The resulting algorithm proves to be highly competitive when it is applied on the whole set of the DIMACS benchmark graphs.
Linguistic data mining with fuzzy FP-trees
Authors: Chun-Wei Lin, Tzung-Pei Hong, Wen-Hsiang Lu
Venue: Expert Systems with Applications: An International Journal (2010)

Due to the increasing occurrence of very large databases, mining useful information and knowledge from transactions is evolving into an important research area. In the past, many algorithms were proposed for mining association rules, most of which were based on items with binary values. Transactions with quantitative values are, however, commonly seen in real-world applications. In this paper, the frequent fuzzy pattern tree (fuzzy FP-tree) is proposed for extracting frequent fuzzy itemsets from the transactions with quantitative values. When extending the FP-tree to handle fuzzy data, the processing becomes much more complex than the original since fuzzy intersection in each transaction has to be handled. The fuzzy FP-tree construction algorithm is thus designed, and the mining process based on the tree is presented. Experimental results on three different numbers of fuzzy regions also show the performance of the proposed approach.
Numerical implementation of a novel accurate stress integration scheme of the von Mises elastoplasticity model with combined linear hardening
Authors: Attila Kossa, László Szabó
Venue: Finite Elements in Analysis and Design (2010)

Recently, the authors proposed a new integration scheme for the von Mises elastoplasticity model with combined linear isotropic-kinematic hardening. In this paper, the numerical accuracy and the computational efficiency of this method are examined in detail. In addition, the key issues of its numerical implementation are also discussed. The main advantage of the novel approach is that it is based on an exact solution of the governing rate constitutive equations. However, it should be noted that computationally the most expensive part of the novel stress update formulas is the inversion of an incomplete beta function, for which task, an efficient and accurate method was developed, based on nested derivatives. In order to evaluate the computational performance of the new scheme with regards to in finite element (FE) calculations, the method was implemented in the commercial FE software package ABAQUS/Standard via its UMAT material interface. The numerical accuracy and computational speed of the new integration technique were compared to the ABAQUS internal stress integration scheme by solving some FE examples. Based on the results of these numerical experiments one can conclude that the new method is faster than the ABAQUS internal scheme if higher accuracy is required. This advantage shows the usefulness of the new method in elastic-plastic FE calculations.
Default interactions for multi-agent simulations of complex organizations
Authors: Nick Szirbik, Marco Stuit
Venue: Proceedings of the International Workshop on Enterprises & Organizational Modeling and Simulation (2009)

Default interactions are a novel concept that supports the agent-based simulation framework and modeling toolset that is built around the TALL language. This paper argues that default interactions are ubiquitous in business processes that are mostly constituted and driven by human interactions. Therefore, it is necessary to make the default interactions explicit by developing and imposing protocols for their execution. The paper shows how interactions that otherwise need a very complex execution scheme can be radically simplified by employing various types of default interactions, depending on the type of the organization that is modeled and simulated.
Brief paper: Multipliers for model predictive control with structured input constraints
Authors: W. P. Heath, Guang Li
Venue: Automatica (Journal of IFAC) (2010)

The stability and robustness of input-constrained model predictive control can be analyzed using the theory of integral quadratic constraints. We demonstrate the existence of improved multipliers when there are only staged input or box input constraints. This can significantly reduce the conservatism of any stability analysis, and we illustrate the improved performance with a simple numerical example.
Bi-objective group scheduling in hybrid flexible flowshop: A multi-phase approach
Authors: N. Karimi, M. Zandieh, H. R. Karamooz
Venue: Expert Systems with Applications: An International Journal (2010)

This study strives to minimize multi-objective flexible flowshop considering sequence-dependent setup times. The flowshop scheduling problem made up of n jobs that have to be processed on m machine. But a flexible flowshop scheduling problem should have more than one machine in at least one stage. As this problem is proven to be NP-hard, a multi-phase approach is developed to solve it. Both phases two and three improve their previous phase solutions, in order to tackle with the complexity of being multi-objective optimization, Pareto archive concepts have been implemented here. The parameters of the proposed algorithm are calibrated using a design of experiment (DOE) method. We investigate the performance of our algorithm through comparing two last stage of it with a distinguished benchmark, multi-objective genetic algorithm (MOGA). The computational results support the high performance of our innovative algorithm.
Routing to develop expertise in customer contact centers
Authors: Alexandre Brandwajn
Venue:  (2009)

A call center often serves as the principal or only point of contact between a company and its customers, and the cost of staffing the center with suitably skilled agents is a large proportion of its operating costs. In this environment, the efficiency and quality with which agents handle customer encounters determines the economic productivity of the call center. This research describes the performance of routing policies for inbound call center traffic that trade off two conflicting objectives: minimizing the waiting time for customers, and specialized on-the-job skill acquisition by agents that improves the customer experience. Empirical results for agent productivity trends are derived from individual summary data for 2.7 million calls taken over the course of 2007 by a financial service call center. This unique data set describes both service time and service quality for 178 separate types of inquiries, regarding diverse subjects such as credit card billing, tax advice, and sales of investment products. Service quality is measured independently of an agents own assessment by recording the resolution status of each call: does the record show this customer finds it necessary to call again about the same issue, or has this problem been resolved successfully? Observations from this data show that the notion of expertise may be characterized by convex functions of cumulative production. Analytical results are then obtained for utility functions of the agents expertise: the customers utility, encouraging specialized expertise; and the supervisors utility, encouraging an even distribution of expertise among agents. These utility functions guide the development of nonlinear programs that set expertise targets, in the form of work assignments, for call center staff who are observed to have varying abilities. Routing rules to implement these work assignments are then analyzed, using simulations of call center operations in the presence of stochastically varying customer arrival and departure times. The research describes how well-targeted priority rules achieve higher levels of service experienced by customers, with minimal effects on the time spent waiting to be served. 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
Recognizing objects on cluttered backgrounds
Authors: Katarina Mele, Jasna Maver
Venue: Pattern Recognition Letters (2005)

This paper deals with recognition of known 3-D objects in different orientations on cluttered backgrounds. As a recognition technique we apply support vector machines (SVMs). To cope with the cluttered background a tree structure of masks is introduced for each object. SVMs are then computed by masking the training sets with the appropriate masks. One- and two-class SVMs are combined in the recognition process. One-class SVMs, used at the first stage, allow us to avoid the ''non-object'' class generation usually required to classify unknown objects or other parts of a scene. Two-class SVMs are further applied to resolve the recognition process when necessary. The proposed method is compared with two other approaches and as demonstrated by experimental results it is robust to cluttered backgrounds. The advantage of the method is its ability to classify the pattern as unknown which has a valuable effect on false positive rate.
Application of GA to optimize cutting conditions for minimizing surface roughness in end milling machining process
Authors: Azlan Mohd Zain, Habibollah Haron, Safian Sharif
Venue: Expert Systems with Applications: An International Journal (2010)

This study is carried out to observe the optimal effect of the radial rake angle of the tool, combined with speed and feed rate cutting conditions in influencing the surface roughness result. In machining, the surface roughness value is targeted as low as possible and is given by the value of the optimal cutting conditions. By looking at previous studies, as far as they have been reviewed, it seems that the application of GA optimization techniques for optimizing the cutting conditions value of the radial rake angle for minimizing surface roughness in the end milling of titanium alloy is still not given consideration by researchers. Therefore, having dealt with radial rake angle machining parameter, this study attempts the application of GA to find the optimal solution of the cutting conditions for giving the minimum value of surface roughness. By referring to the real machining case study, the regression model is developed. The best regression model is determined to formulate the fitness function of the GA. The analysis of this study has proven that the GA technique is capable of estimating the optimal cutting conditions that yield the minimum surface roughness value. With the highest speed, lowest feed rate and highest radial rake angle of the cutting conditions scale, the GA technique recommends 0.138@mm as the best minimum predicted surface roughness value. This means the GA technique has decreased the minimum surface roughness value of the experimental sample data, regression modelling and response surface methodology technique by about 27%, 26% and 50%, respectively.
A DEMATEL method in identifying key success factors of hospital service quality
Authors: Jiunn-I Shieh, Hsin-Hung Wu, Kuan-Kai Huang
Venue: Knowledge-Based Systems (2010)

Since National Health Insurance program formally went into effect in March 1995 in Taiwan, the residents enjoy high quality but relatively cheaper medical care compared with the most developed countries. To manage a hospital successfully, the important goals are to attract and then retain as many patients as possible by meeting potential demands of various kinds of the patients. This study first conducted the survey based on SERVQUAL model to identify seven major criteria from patients' or their families' viewpoints at Show Chwan Memorial Hospital in Changhua City, Taiwan. When the key criteria were found, the second survey developed for applying decision-making trial and evaluation laboratory (DEMATEL) method was issued to the hospital management by evaluating the importance of criteria and constructing the causal relations among the criteria. The results show that trusted medical staff with professional competence of health care is the most important criterion and mutually affects service personnel with good communication skills, service personnel with immediate problem-solving abilities, detailed description of the patient's condition by the medical doctor, and medical staff with professional abilities. Therefore, trainings on communication skills and problem-solving abilities would result in positive interaction for patients to trust medical staff. When the trusted medical staff provides professional competence of health care to patients, satisfaction would be increased.
Sufficient conditions for Carathéodory functions
Authors: In Hwa Kim, Nak Eun Cho
Venue: Computers Mathematics with Applications (2010)

The purpose of the present paper is to derive some sufficient conditions for Caratheodory functions in the open unit disk by using Miller and Mocanu's lemma. Several special cases are considered as the corollaries of main results.
The quadratic MITC plate and MITC shell elements in plate bending
Authors: Phill-Seung Lee, Klaus-Jürgen Bathe
Venue: Advances in Engineering Software (2010)

The analysis of plates can be achieved using the quadratic MITC plate or MITC shell elements. The plate elements have a strong mathematical basis and have been shown to be optimal in their convergence behavior, theoretically and numerically. The shell elements have not (yet) been analyzed mathematically in depth for their rates of convergence, with the plate/shell thickness varying, but have been shown numerically to perform well. Since the shell elements are general and can be used for linear and nonlinear analyses of plates and shells, it is important to identify the differences in the performance of these elements when compared to the plate elements. We briefly review the quadratic quadrilateral and triangular MITC plate and shell elements and study their performances in linear plate analyses.