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Abstract

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Mathematical and Economic Theory of Road Pricing
Type: Book
ISBN: 978-0-08-045671-3

Article
Publication date: 4 July 2016

Qingdong Zhang, Boyang Zhang and Xingfu Lu

The purpose of this paper is to propose a hybridization numerical method to solve the plastic deformation of metal working based on the flow function method and meshless method…

Abstract

Purpose

The purpose of this paper is to propose a hybridization numerical method to solve the plastic deformation of metal working based on the flow function method and meshless method.

Design/methodology/approach

The proposed method is named as flow function-element free Galerkin (F-EFG) method. It uses the flow function as the basic unknown quantity to get the basic control equation, the compactly supported approximate function to establish a local approximate flow function by means of moving least square approximation, and the element free Galerkin (EFG) method to solve variational equation. The F-EFG method takes the upper limit method essence of flow function method, and the convergence, stability, and error characteristics of EFG method.

Findings

The steady extrusion process of the axisymmetric extrusion problems as well as the extrusion deformation law and main field variables are subjects in the modeling and simulation analysis using F-EFG method. The results show that the F-EFG method has good computational efficiency and accuracy.

Originality/value

The F-EFG method proposed in this paper has the advantages of high-solution precision of flow function method and large deformation solution of element free method. It overcomes the difficulties in global flow function establishment in flow function method and low-solution efficiency in element free method. The method is beneficial to the development of flow function method and element free method.

Details

Engineering Computations, vol. 33 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Abstract

Details

Fundamentals of Transportation and Traffic Operations
Type: Book
ISBN: 978-0-08-042785-0

Abstract

Details

Mathematical and Economic Theory of Road Pricing
Type: Book
ISBN: 978-0-08-045671-3

Article
Publication date: 11 October 2011

Dereje Engida Woldemichael and Fakhruldin Mohd Hashim

The purpose of this paper is to describe the framework of conceptual design support tool (CDST) developed to assist designers during conceptual design process. The premise of the…

2729

Abstract

Purpose

The purpose of this paper is to describe the framework of conceptual design support tool (CDST) developed to assist designers during conceptual design process. The premise of the study is that, by combining human creativity with computer capabilities, it is possible to perform conceptual design process more efficiently than solely manual design. The study aims to show how conceptual design knowledge can be captured from experienced designers and kept in the computer system for later use and how the developed tool assists designers by handling some of the repetitive and time‐consuming tasks.

Design/methodology/approach

A conceptual design process model, which integrates systematic design approach with knowledge‐based system, is proposed. Based on this model, a CDST, which consists of function library, alternative concepts database, different modules for conceptual design activities, and a knowledge‐based system is developed. The alternative concepts database is built based on design reuse philosophy. Furthermore, the tool is designed to accept and save new concepts from the user through its knowledge acquisition module without modifying the source code. The CDST is developed using public domain open source programming environments namely CLIPS, Python, wxPython, and PyCLIPS.

Findings

Through its graphical user interface, CDST assists designers in performing the conceptual design process such as functional modelling, using standard vocabularies of functions, generating concepts and displaying on morphology chart, concept combination, and concept evaluation. The functionality and interaction between the user and the CDST is demonstrated with an example.

Research limitations/implications

Currently, the alternative concepts database consists of concepts from subsea process equipment design and few general mechanical designs. The database can be enhanced by adding more concepts through the knowledge acquisition module provided.

Practical implications

The tool can be used as a knowledge management system in industry by capturing expertise knowledge and to train novice designers. It augments designer's knowledge by providing concepts from past designs.

Originality/value

The research output from this paper can be valuable resource in industry to support designers with computers. The research represents one of the attempts to develop domain independent conceptual design tool that can acquire new concepts throughout its lifetime.

Details

Journal of Engineering, Design and Technology, vol. 9 no. 3
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 1 August 1993

Arnold Maltz, Linda Riley and Kevin Boberg

One strategy for dealing with the increasing problem ofcross‐border movement is to involve third‐party specialists. Reports onan investigation of third‐party use in maquiladora or…

Abstract

One strategy for dealing with the increasing problem of cross‐border movement is to involve third‐party specialists. Reports on an investigation of third‐party use in maquiladora or twin‐plant logistics across the US‐Mexico border. A mail survey of 250 companies operating in the El Paso‐Juarex area was carried out. Results showed that the surveyed firms used third parties more than US firms in general.

Details

International Journal of Physical Distribution & Logistics Management, vol. 23 no. 8
Type: Research Article
ISSN: 0960-0035

Keywords

Article
Publication date: 22 August 2023

Mohammadsadegh Pahlavanzadeh, Krzysztof Rusin and Wlodzimierz Wróblewski

The purpose of this study is an assessment of the existing roughness models to simulate the flow in the narrow gap between corotating and rough disks. A specific configuration of…

Abstract

Purpose

The purpose of this study is an assessment of the existing roughness models to simulate the flow in the narrow gap between corotating and rough disks. A specific configuration of the flow through the gap, which forms a minichannel with variable cross sections and rotating walls, makes it a complex problem and, therefore, worth discussing in more detail.

Design/methodology/approach

Two roughness models were examined, the first one was based on the wall function modification by application of the shift in the dimensionless velocity profile, and the second one was based on the correction of turbulence parameters at the wall, proposed by Aupoix. Due to the lack of data to validate that specific case, the approach to deal with was selected after a systematic study of reported test cases. It started with a zero-pressure-gradient boundary layer in the flow over a flat plate, continued with flow through minichannels with stationary walls, and finally, focused on the flow between corotating discs, pertaining each time to smooth and rough surfaces.

Findings

The limitations of the roughness models were highlighted, which make the models not reliable in the application to minichannel flows. It concerns turbulence models, near-wall discretization and roughness approaches. Aupoix’s method to account for roughness was selected, and the influence of minichannel height, mass flow rate, fluid properties and roughness height on the velocity profile between corotating discs in both smooth and rough cases was discussed.

Originality/value

The originality of this study is the evaluation and validation of different methods to account for the roughness in rotating mini channels, where the protrusions can cover a substantial part of the channel. Flow behavior and performance of different turbulence models were analyzed as well.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 12
Type: Research Article
ISSN: 0961-5539

Keywords

Book part
Publication date: 15 December 1998

David Watling

The paper considers a discrete-time, Markov, stochastic process model of drivers' day-to-day evolving route choice, the evolving ‘state’ of such a system being governed by the…

Abstract

The paper considers a discrete-time, Markov, stochastic process model of drivers' day-to-day evolving route choice, the evolving ‘state’ of such a system being governed by the traffic interactions between vehicles, and the adaptive behaviour of drivers in response to previous travel experiences. An approximating deterministic process is proposed, by approximating both the probability distribution of previous experiences—the “memory filter”—and the conditional distribution of future choices. This approximating process includes both flow means and variances as state variables. Existence and uniqueness of fixed points of this process are examined, and an example used to contrast these with conventional stochastic equilibrium models. The elaboration of this approach to networks of an arbitrary size is discussed.

Details

Mathematics in Transport Planning and Control
Type: Book
ISBN: 978-0-08-043430-8

Article
Publication date: 1 May 1983

In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of…

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Abstract

In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of material poses problems for the researcher in management studies — and, of course, for the librarian: uncovering what has been written in any one area is not an easy task. This volume aims to help the librarian and the researcher overcome some of the immediate problems of identification of material. It is an annotated bibliography of management, drawing on the wide variety of literature produced by MCB University Press. Over the last four years, MCB University Press has produced an extensive range of books and serial publications covering most of the established and many of the developing areas of management. This volume, in conjunction with Volume I, provides a guide to all the material published so far.

Details

Management Decision, vol. 21 no. 5
Type: Research Article
ISSN: 0025-1747

Keywords

Abstract

Details

Handbook of Transport Modelling
Type: Book
ISBN: 978-0-08-045376-7

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