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Modeling Capabilities (modeling + capability)

Distribution by Scientific Domains

Engineering	50%

Selected Abstracts

A Modeling Framework for Supply Chain Simulation: Opportunities for Improved Decision Making,

DECISION SCIENCES, Issue 1 2005
D. J. Van Der Zee
ABSTRACT Owing to its inherent modeling flexibility, simulation is often regarded as the proper means for supporting decision making on supply chain design. The ultimate success of supply chain simulation, however, is determined by a combination of the analyst's skills, the chain members' involvement, and the modeling capabilities of the simulation tool. This combination should provide the basis for a realistic simulation model, which is both transparent and complete. The need for transparency is especially strong for supply chains as they involve (semi)autonomous parties each having their own objectives. Mutual trust and model effectiveness are strongly influenced by the degree of completeness of each party's insight into the key decision variables. Ideally, visual interactive simulation models present an important communicative means for realizing the required overview and insight. Unfortunately, most models strongly focus on physical transactions, leaving key decision variables implicit for some or all of the parties involved. This especially applies to control structures, that is, the managers or systems responsible for control, their activities and their mutual attuning of these activities. Control elements are, for example, dispersed over the model, are not visualized, or form part of the time-indexed scheduling of events. In this article, we propose an alternative approach that explicitly addresses the modeling of control structures. First, we will conduct a literature survey with the aim of listing simulation model qualities essential for supporting successful decision making on supply chain design. Next, we use this insight to define an object-oriented modeling framework that facilitates supply chain simulation in a more realistic manner. This framework is meant to contribute to improved decision making in terms of recognizing and understanding opportunities for improved supply chain design. Finally, the use of the framework is illustrated by a case example concerning a supply chain for chilled salads. [source]

Implementation of the finite element method in the three-dimensional discontinuous deformation analysis (3D-DDA)

INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 15 2008
Roozbeh Grayeli
Abstract A modified three-dimensional discontinuous deformation analysis (3D-DDA) method is derived using four-noded tetrahedral elements to improve the accuracy of current 3D-DDA algorithm in practical applications. The analysis program for the modified 3D-DDA method is developed in a C++ environment and its accuracy is illustrated through comparisons with several analytical solutions that are available for selected problems. The predicted solutions for these problems using the modified 3D-DDA approach all show satisfactory agreement with the corresponding analytical results. Results presented in this paper demonstrate that the modified 3D-DDA method with discontinuous modeling capabilities offers a useful computational tool to determine stresses and deformations in practical problems involving fissured elastic media with reasonable accuracy. Copyright © 2008 John Wiley & Sons, Ltd. [source]

On the meta-knowledge choquet integral and related models

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 10 2005
Vicenç Torra
Choquet integral and multistep Choquet integrals have been used in recent years as models for decision making and information aggregation. Such models can be used to fuse information when information sources are not independent. A basic property of such models is that their output is monotonically increasing with respect to inputs. In this article we study two alternative models built on the basis of such Choquet integrals. The motivation is, on the one hand, to study the modeling capabilities of such operators and, on the other, to build models that are capable of approximating any arbitrary functions (not only monotonic ones). In this article we describe and study two models that are universal approximators. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 1017,1036, 2005. [source]

Enhancing Neural Network Traffic Incident-Detection Algorithms Using Wavelets

COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2001
A. Samant
Researchers have presented freeway traffic incident-detection algorithms by combining the adaptive learning capability of neural networks with imprecision modeling capability of fuzzy logic. In this article it is shown that the performance of a fuzzy neural network algorithm can be improved through preprocessing of data using a wavelet-based feature-extraction model. In particular, the discrete wavelet transform (DWT) denoising and feature-extraction model proposed by Samant and Adeli (2000) is combined with the fuzzy neural network approach presented by Hsiao et al. (1994). It is shown that substantial improvement can be achieved using the data filtered by DWT. Use of the wavelet theory to denoise the traffic data increases the incident-detection rate, reduces the false-alarm rate and the incident-detection time, and improves the convergence of the neural network training algorithm substantially. [source]