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Article
Publication date: 1 January 2005

Joseph W.K. Chan

Sets out an exploratory study to give an alternative viewpoint of manufacturing logistics.

Abstract

Purpose

Sets out an exploratory study to give an alternative viewpoint of manufacturing logistics.

Design/methodology/approach

Based on causal analysis, the relationship between competitive strategy and manufacturing logistics was explored. Variables, including both positioning and competitive dimensions, in the competitive strategy that interacted with manufacturing logistics were identified. The elements of manufacturing logistics for this study included master production scheduling, capacity requirements planning, material planning, purchasing, and inventory control. A weighted business performance index was used to segregate the sample firms into three groups: high‐, average‐, and low‐performing organizations. For each of the performance group, the causal relationships between strategic elements and the performance of manufacturing logistics were then analyzed.

Findings

The results showed a significant relationship between competitive strategy and manufacturing logistics system performance.

Research/limitations/implications

Not all the elements in manufacturing logistics may contribute to the logistics performance. The construct of manufacturing logistics depends on a particular set of strategic variables that the organization designs.

Originality/value

Extends the study of manufacturing logistics beyond its boundary through a broader strategic perspective.

Details

International Journal of Physical Distribution & Logistics Management, vol. 35 no. 1
Type: Research Article
ISSN: 0960-0035

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Article
Publication date: 1 August 2002

Joseph W.K. Chan and N.D. Burns

Examines the manufacturing planning and control (MPC) systems in three supply chain environments in Hong Kong, based on a questionnaire survey. Studies five MPC modules…

Abstract

Examines the manufacturing planning and control (MPC) systems in three supply chain environments in Hong Kong, based on a questionnaire survey. Studies five MPC modules: master production scheduling; capacity requirements planning; material planning; purchasing; and inventory control. Studies the performance of each MPC module. The supply chain environments that are taken into consideration include agile, leagile, and lean. Based on a weighted organizational performance index, the sample organizations are segregated into three groups: high, average, and low performers. For each of the performance groups, benchmarks the performance ratings of the MPC system and its five modules, subject to different supply chain environments. Concludes that: MPC system performance really has a positive effect upon organization performance; four of the proposed benchmarking modules of the MPC systems can be used to assess an organization’s strengths and weaknesses with regard to their use in planning and control of manufacture; and supply chain strategy may associate with the MPC system performance.

Details

Benchmarking: An International Journal, vol. 9 no. 3
Type: Research Article
ISSN: 1463-5771

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Article
Publication date: 18 October 2011

Endra Joelianto, Edwina Maryami Sumarjono, Agus Budiyono and Dini Retnaning Penggalih

The purpose of this paper is to investigate the feasibility of controlling a small‐scale helicopter by using the model predictive control (MPC) method.

Abstract

Purpose

The purpose of this paper is to investigate the feasibility of controlling a small‐scale helicopter by using the model predictive control (MPC) method.

Design/methodology/approach

The MPC control synthesis is employed by considering five linear models representing the flight of a small‐scale helicopter from hover to high‐speed cruise. The internal model principle is employed for the trajectory tracking design.

Findings

It is found that the MPC handles well the transition problems between the models, yields satisfactory tracking control performance and produces a suitable control signal. The performance of the tracking control of the helicopter is considerably influenced by the parameter selection in the states and inputs weighting matrices of the MPC. Simulation results also showed that faster dynamics, coupling problems, input and output constraints and changing linearized multi‐inputs multi‐outputs dynamics models in the small‐scale helicopter can be handled simultaneously by the MPC controller.

Research limitations/implications

The present study is limited for the application of MPC for the control of small‐scale helicopters with non‐aggressive maneuvers.

Practical implications

The result can be extended to design a full envelope controller for an autonomous small‐scale helicopter without the need to resort to a conventional gain scheduling technique.

Originality/value

Helicopter control system designs using MPC with a single either linear or non‐linear model have been studied and reported in numerous literatures. The main contribution of the paper is in the application of MPC to handle the control problems of a small‐scale helicopter defined as a mathematical model with several different modes during a flight mission.

Details

Aircraft Engineering and Aerospace Technology, vol. 83 no. 6
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 11 February 2021

Houda Laabidi, Houda Jouini and Abdelkader Mami

The purpose of this paper is to propose an efficient current control technique based on model predictive control (MPC) for grid-connected wind conversion system. This…

Abstract

Purpose

The purpose of this paper is to propose an efficient current control technique based on model predictive control (MPC) for grid-connected wind conversion system. This nonlinear strategy is applied for the chopper circuit and grid-tied inverter and compared with other two conventional schemes; a traditional proportional-integral (PI) and sliding mode controller (SMC) using the same switching frequency.

Design/methodology/approach

Firstly, the MPC scheme uses the mathematical model to predict future behaviors of the controlled converter outputs for possible switching states. After that, the optimal voltage vector is selected by minimizing a cost function, which is defined as a sum of the absolute values of the controlled current errors. Then, the corresponding switching signals are applied to the converter switches in the next sampling period to track correctly the reference current. Thus, the MPC scheme ensures a minimal error between the predicted and reference trajectories of the considered variables.

Findings

The MPC-based algorithm presents several benefits in terms of high accuracy control, reduced DC-link voltage ripples during steady-state operation, faster transient response, lower overshoots and disturbance rejection and acceptable total harmonic distortion.

Originality/value

The authors introduce several simulation case studies, using PSIM software package, which prove the reliability and effectiveness of the proposed MPC scheme. Therefore, the MPC performances, during dynamic and steady-state condition, are compared with those obtained by a PI regulator and SMC to highlight the improvements, specifically the transfer of smooth power to the grid.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 13 March 2020

Hongshuai Gao and Quansheng Sun

With the rapid development of transportation and the continuous increase of traffic volume and load level, some bridges cannot meet the use requirements, and the demand…

Abstract

Purpose

With the rapid development of transportation and the continuous increase of traffic volume and load level, some bridges cannot meet the use requirements, and the demand for bridge strengthening is growing. Furthermore, bridges are affected by factors such as structure and external environment. With the increase of service time, the deterioration of bridges is also increasing. In order to avoid the waste caused by demolition and reconstruction, it is necessary to strengthen the bridge accurately and effectively to improve the bearing capacity and durability, eliminate the hidden dangers, and ensure the normal operation of the bridge. It is of great significance to study the strengthening methods. Compared with traditional strengthening methods, the advantages of using new materials and new technology to strengthen bridges are more obvious. This paper introduces a new method for bridge active strengthening, called modified polyurethane cement with prestressed steel wire rope (MPC-PSWR).

Design/methodology/approach

Relying on the actual bridge strengthening project, five T-beams of the superstructure of the bridge are taken as the research object, and the T-beams before and after strengthening are evaluated, calculated, and analyzed by finite element simulation and field load test. By comparing the numerical simulation and load test data, the strengthening effect of modified polyurethane cement with prestressed steel wire rope on stiffness, strength, and bearing capacity is verified, which proves that the strengthening effect of MPC-PSWR is effective for strengthening.

Findings

MPC-PSWR can effectively reduce deflection, cracks, and strain, thereby significantly improving the flexural capacity of existing bridges. Under the design load, the deflection, crack width, and stress of the strengthened beams decrease in varying degrees. The overall performance of the beams strengthened by MPC-PSWR has been improved, and the flexural performance meets the requirements of the code.

Originality/value

MPC-PSWR is an innovative bridge-strengthening method. Through the analysis of its MPC-PSWR effect, the MPC-PSWR method with reference to significance for the design and construction of similar bridges is put forward.

Details

International Journal of Structural Integrity, vol. 11 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 27 April 2020

Lipeng Wang, Zhi Zhang, Qidan Zhu and Xingwei Jiang

This paper aims to propose a novel model predictive control (MPC) with time varying weights to develop a lateral control law in an automatic carrier landing system (ACLS)…

Abstract

Purpose

This paper aims to propose a novel model predictive control (MPC) with time varying weights to develop a lateral control law in an automatic carrier landing system (ACLS), which minimizes landing risk and improves flight quality.

Design/methodology/approach

First, a nonlinear mathematic model of an F/A-18 aircraft during lateral landing is established. Then the landing model is linearized in the form of state deviations on the equilibrium points. Second, landing risk windows are proposed and a high-dimensional landing risk model is addressed through a back propagation (BP) neural network. The trained samples are acquired based on a pilot behavior model. Third, time varying weights created from the lateral landing risk are introduced into the performance function of MPC. Optimal solution is solved quicker and some state deviations are focused on and eliminated. Fourth, the algebraic inequalities are substituted by the linear matrix inequalities (LMIs), which are easily calculated by the computers.

Findings

On a semi-physical platform, the proposed method compares with a traditional MPC algorithm and a modified MPC with an additional term. The test results indicate that the proposed algorithm brings about an excellent landing performance as well as an ability of eliminating landing risk.

Practical implications

The landing phase of a carrier-based aircraft is one of the most dangerous and complicated stages, and the algorithm proposed by this paper plays a vital role in the lateral landing.

Originality/value

This paper establishes a lateral landing risk model, which considers not only the current landing state but also the future touchdown point. This lateral landing risk is integrated into the time varying weights of the MPC algorithm so that the state deviations and landing risk can be both reduced in the rolling optimization.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

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Article
Publication date: 1 August 1998

Alexander Howard, Ashok Kochhar and John Dilworth

Outlines an objective model based approach for the functional specification of manufacturing planning and control (MPC) systems. It is based on the premise that there is…

Abstract

Outlines an objective model based approach for the functional specification of manufacturing planning and control (MPC) systems. It is based on the premise that there is factual information (company characteristics and management concerns) which can be used to make recommendations about suitable functionality of appropriate MPC systems. A generic MPC system architecture, applicable to medium‐sized batch manufacturing companies, is used to organise the information within the model. The model describes the relationships between the inputs (objective company characteristics and subjective management concerns) and outputs (MPC functional activities). The functional activities have been defined at a level of detail which represents significant choices in functionality and are useful for the functional specification of MPC systems. The model provides reasoning which describes the relevance of the activities in individual cases. Uses field studies to validate and test the elements of the model (inputs, outputs and reasoning). Uses the model output to create an outline functional specification at each of the field study sites. Concludes that the model can be used to obtain an objective view of necessary functionality in MPC systems in medium‐sized batch manufacturing companies. The output from the model can be used as the basis for the development of a final, detailed functional specification. Use of the model results in time savings.

Details

International Journal of Operations & Production Management, vol. 18 no. 8
Type: Research Article
ISSN: 0144-3577

Keywords

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Article
Publication date: 1 August 1995

W. Rocky Newman and V. Sridharan

A manufacturing planning and control (MPC) system is a major partof the infrastructure used by a firm to enhance its competitiveposition. Although a clear understanding of…

Abstract

A manufacturing planning and control (MPC) system is a major part of the infrastructure used by a firm to enhance its competitive position. Although a clear understanding of the mechanics and benefits of alternative MPC systems exists, very little is known about the relationships between such systems, the strategic environment faced by the user‐firms, and their performance in achieving cost/competitive advantage. Historically, the choice of an MPC system appears to have been made based solely on available in‐house expertise, industry trends, or plain inertia. Reports a summary of the results of a survey conducted to explore empirically the relationship between the environmental characteristics faced by the manufacturing function and manufacturing performance of firms using alternative MPC systems. Presents the results of an analysis of the environment faced by best and worst performers using different MPC systems. The results indicate key linkages between the MPC systems, environment, and performance.

Details

Integrated Manufacturing Systems, vol. 6 no. 4
Type: Research Article
ISSN: 0957-6061

Keywords

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Article
Publication date: 1 February 1993

Anatoly V. Zhuplev

Describes the birth and demise of the Moscow Personnel Centre. TheCentre was founded as a city‐sponsored independent consulting companywhich developed numerous different…

Abstract

Describes the birth and demise of the Moscow Personnel Centre. The Centre was founded as a city‐sponsored independent consulting company which developed numerous different personnel and counselling services. Due to an unfocused strategy and inability to secure the support of the new Moscow city government, the Personnel Centre broke apart in 1991.

Details

Journal of Organizational Change Management, vol. 6 no. 2
Type: Research Article
ISSN: 0953-4814

Keywords

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Article
Publication date: 1 May 2001

Corrinne S. Shearer, David S. Hames and Janet B. Runge

Research has demonstrated that mergers and acquisitions often fail, in significant part because companies fail to effectively integrate their diverse organizational…

Abstract

Research has demonstrated that mergers and acquisitions often fail, in significant part because companies fail to effectively integrate their diverse organizational cultures. This case study provides an in‐depth description of one company’s organizational culture just prior to being acquired, and demonstrates how it began to change almost immediately following the acquisition. The new CEO affected the acquired company’s culture directly by changing roles, responsibilities, policies, procedures, and practices. He affected it indirectly through his influence on other organizational members. Suggestions for effectively managing the integration of diverse organizational cultures following an acquisition are discussed.

Details

Leadership & Organization Development Journal, vol. 22 no. 3
Type: Research Article
ISSN: 0143-7739

Keywords

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