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Abstract

Details

Optimal Growth Economics: An Investigation of the Contemporary Issues and the Prospect for Sustainable Growth
Type: Book
ISBN: 978-0-44450-860-7

Article
Publication date: 1 July 2002

Amar Khoukhi

In this paper the problem of the dynamic optimal time‐energy Off‐Line programming of an autonomous mobile robot in a crowded environment is considered. First, kinematic model and…

Abstract

In this paper the problem of the dynamic optimal time‐energy Off‐Line programming of an autonomous mobile robot in a crowded environment is considered. First, kinematic model and planning are presented. Then a dynamic model based on Euler‐Lagrange formalism is developed and a mobility estimation function of the robot is considered. This dynamic estimation of the robot mobility takes into account of the velocity and the orientation of the robot. Then the scene structuration and a path finder algorithm are developed. After, the optimal dynamic off‐line programming is formulated as a nonlinear programming problem under nonlinear equality and inequality constraints. The Discrete Augmented Lagrangian (DAL) is used to obtain the optimal trajectograhy. We develop an extended DAL to DALAP, DALAdaptive Penalty. RoboSim 1.0 simulator is developed to perform kinematic and DALAP based algorithms on a large class of mobile robots optimal time‐energy off‐line programming. A comparative study with kinematic planning is considered. It is shown that the performance of the dynamic optimal time‐energy control and off‐line programming is much better than kinematic and heuristic based schemes. This strategy of trajectory planning was implemented on the case study of the SARA mobile robot model.

Details

Kybernetes, vol. 31 no. 5
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 February 1972

W.W. Swart, C.E. Gearing and T. Var

In a companion paper (1) a general mathematical model for the allocation of touristic investments was developed. In this paper a solution methodology for the model is developed…

Abstract

In a companion paper (1) a general mathematical model for the allocation of touristic investments was developed. In this paper a solution methodology for the model is developed based on the principles of dynamic programming. At each stage of the dynamic program an integer program is solved to limit the range of values of the state variable which must explicitly be considered. The algorithm is illustrated through an example, and the advantages of the solution procedure are explained by considering the solution as a base for the strategic decision making in the touristic sector.

Details

The Tourist Review, vol. 27 no. 2
Type: Research Article
ISSN: 0251-3102

Article
Publication date: 28 July 2020

Antti Salonen and Maheshwaran Gopalakrishnan

The purpose of this study was to assess the readiness of the Swedish manufacturing industry to implement dynamic, data-driven preventive maintenance (PM) by identifying the gap…

Abstract

Purpose

The purpose of this study was to assess the readiness of the Swedish manufacturing industry to implement dynamic, data-driven preventive maintenance (PM) by identifying the gap between the state of the art and the state of practice.

Design/methodology/approach

An embedded multiple case study was performed in which some of the largest companies in the discrete manufacturing industry, that is, mechanical engineering, were surveyed regarding the design of their PM programmes.

Findings

The studied manufacturing companies make limited use of the existing scientific state of the art when designing their PM programmes. They seem to be aware of the possibilities for improvement, but they also see obstacles to changing their practices according to future requirements.

Practical implications

The results of this study will benefit both industry professionals and academicians, setting the initial stage for the development of data-driven, diversified and dynamic PM programmes.

Originality/Value

First and foremost, this study maps the current state and practice in PM planning among some of the larger automotive manufacturing industries in Sweden. This work reveals a gap between the state of the art and the state of practice in the design of PM programmes. Insights regarding this gap show large improvement potentials which may prove important for academics as well as practitioners.

Details

Journal of Quality in Maintenance Engineering, vol. 27 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 1 May 1990

Usha Sharma and K.B. Misra

A large number of research articles have appeared in the literature during the last two decades on the subject of system reliability optimisation, each with a view to providing…

Abstract

A large number of research articles have appeared in the literature during the last two decades on the subject of system reliability optimisation, each with a view to providing simple, exact and efficient techniques. Here, an efficient, fast and exact technique is proposed for solving integer‐programming problems that normally arise in optimal reliability design problems. The algorithm presented is superior to any of the earlier methods available so far, being based on functional evaluations and a limited systematic search close to the boundary of resources. Thus it can quickly solve even very large system problems. It can also be effectively used with other operations research problems involving integer‐programming formulations.

Details

International Journal of Quality & Reliability Management, vol. 7 no. 5
Type: Research Article
ISSN: 0265-671X

Keywords

Open Access
Article
Publication date: 26 December 2023

Mehmet Kursat Oksuz and Sule Itir Satoglu

Disaster management and humanitarian logistics (HT) play crucial roles in large-scale events such as earthquakes, floods, hurricanes and tsunamis. Well-organized disaster response…

Abstract

Purpose

Disaster management and humanitarian logistics (HT) play crucial roles in large-scale events such as earthquakes, floods, hurricanes and tsunamis. Well-organized disaster response is crucial for effectively managing medical centres, staff allocation and casualty distribution during emergencies. To address this issue, this study aims to introduce a multi-objective stochastic programming model to enhance disaster preparedness and response, focusing on the critical first 72 h after earthquakes. The purpose is to optimize the allocation of resources, temporary medical centres and medical staff to save lives effectively.

Design/methodology/approach

This study uses stochastic programming-based dynamic modelling and a discrete-time Markov Chain to address uncertainty. The model considers potential road and hospital damage and distance limits and introduces an a-reliability level for untreated casualties. It divides the initial 72 h into four periods to capture earthquake dynamics.

Findings

Using a real case study in Istanbul’s Kartal district, the model’s effectiveness is demonstrated for earthquake scenarios. Key insights include optimal medical centre locations, required capacities, necessary medical staff and casualty allocation strategies, all vital for efficient disaster response within the critical first 72 h.

Originality/value

This study innovates by integrating stochastic programming and dynamic modelling to tackle post-disaster medical response. The use of a Markov Chain for uncertain health conditions and focus on the immediate aftermath of earthquakes offer practical value. By optimizing resource allocation amid uncertainties, the study contributes significantly to disaster management and HT research.

Details

Journal of Humanitarian Logistics and Supply Chain Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2042-6747

Keywords

Article
Publication date: 20 March 2007

Jun‐Geol Baek

Condition‐based maintenance (CBM) has increasingly drawn attention in industry because of its many benefits. The CBM problem is a kind of state‐dependent scheduling problem, and…

1656

Abstract

Purpose

Condition‐based maintenance (CBM) has increasingly drawn attention in industry because of its many benefits. The CBM problem is a kind of state‐dependent scheduling problem, and is very hard to solve within the conventional Markov decision process framework. The purpose of this paper is to present an intelligent CBM scheduling model for which incremental decision tree learning as an evolutionary system identification model and dynamic programming as a control model are developed.

Design/methodology/approach

To fully exploit the merits of CBM, this paper models CBM scheduling as a state‐dependent, sequential decision‐making problem. The objective function is formulated as the minimization of the total maintenance cost. Instead of interpreting the problem within the widely used Markovian framework, this paper proposes an intelligent maintenance scheduling approach that integrates an incremental decision tree learning method and deterministic dynamic programming techniques.

Findings

Although the intelligent maintenance scheduling approach proposed in this paper does not guarantee an optimal scheduling policy from a mathematical viewpoint, it is verified through a simulation‐based experiment that the intelligent maintenance scheduler is capable of providing a good scheduling policy that can be used in practice.

Originality/value

This paper presents an intelligent maintenance scheduler. As a system identification model, we devise a new incremental decision tree learning method by which interaction patterns among attributes and machine condition are disclosed in an evolutionary manner. A deterministic dynamic programming technique is then applied to select the best safe state in terms of the total maintenance cost.

Details

International Journal of Quality & Reliability Management, vol. 24 no. 3
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 28 March 2008

Hongfei Li and Sai Deng

The purpose of this paper is to examine dynamic mapping of holding locations to the animated maps in a library catalog which aims to resolve complex shelving situations, augment…

Abstract

Purpose

The purpose of this paper is to examine dynamic mapping of holding locations to the animated maps in a library catalog which aims to resolve complex shelving situations, augment the user experience in locating library materials and enrich the Online Public Access Catalog (OPAC) by integrating external programming into the Integrated Library System (ILS).

Design/methodology/approach

Dynamic mapping displays animated direction maps for users to locate quickly the items found in the library catalog. The maps are displayed in accordance with various shelving policies. At Wichita State University Libraries, the original bibliographic data are captured from the record results page in the OPAC and transferred to a processing program residing on another server. Instead of transferring ISBN/ISSN (International Standard Book Number/ International Standard Serial Number, as practiced by some libraries) to display the Syndetic cover images, it transfers bibliographic ID and a few other fields from MARC (MAchine‐Readable Cataloging) records to a processing program which queries the ILS database for extracting data needed for the dynamic map processing. The dynamic map system consists of three sections: queried data from the ILS database, programming logic, and dynamic maps.

Findings

Compared to title‐level shelving map displays that have been implemented in some libraries, holding level map displays solve the problem of complex shelving situations, such as a title with multiple copies shelved in different locations and/or in different formats.

Originality/value

This project received very positive feedback from the library community and this paper will provide information to those libraries which are interested in dynamically presenting holding information in their OPAC.

Details

New Library World, vol. 109 no. 3/4
Type: Research Article
ISSN: 0307-4803

Keywords

Article
Publication date: 1 March 1980

John R. King and Alexander S. Spachis

Scheduling is defined by Baker as, “the allocation of resources over time to perform a collection of tasks”. The term facilities is often used instead of resources and the tasks…

Abstract

Scheduling is defined by Baker as, “the allocation of resources over time to perform a collection of tasks”. The term facilities is often used instead of resources and the tasks to be performed may involve a variety of different operations.

Details

International Journal of Physical Distribution & Materials Management, vol. 10 no. 3
Type: Research Article
ISSN: 0269-8218

Article
Publication date: 24 November 2020

Chin-Feng Lai, Yu-Lin Jeng and Sheng-Bo Huang

In a programming course, students often need tutors' assistance to complete learning activities, as they lack enough background knowledge to complete tasks. A further problem is…

Abstract

Purpose

In a programming course, students often need tutors' assistance to complete learning activities, as they lack enough background knowledge to complete tasks. A further problem is that without individual tutoring, the knowledge gap between students increases. Therefore, the authors have proposed an instant response learning supplement tool (IRLST) to support students' learning, in order to facilitate students' independent problem-solving skills.

Design/methodology/approach

The authors divided the students into two groups according to their learning styles: verbal and visual. The IRLST was used to collect and analyze the information on their usage and provide supplementary resources to facilitate their learning. The proposed system also analyzed the student usage, background knowledge and exam scores to assess their academic performance.

Findings

According to the results of statistical analysis, students' learning performance improved significantly, especially low-scoring students. Moreover, as compiler messages were not recognized, students tended to identify the same problems. Thus, it is suggested that teachers not only should focus on improving the students' syntax but also strengthening their background knowledge and debugging skills.

Research limitations/implications

There are two main limitations in this study: (1) as most of the students were in the visual learning group, the size of the groups was impacted, thus it was not possible to establish a control group; (2) one specific version of the IRLST system did not send reliable advice or supplementary content occasionally.

Originality/value

The IRLST developed in this study can be used to provide immediate supplementary resources to help students overcoming programming problems and developing problem-solving skills.

Details

Library Hi Tech, vol. 41 no. 4
Type: Research Article
ISSN: 0737-8831

Keywords

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