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Article

Xiang Li and Ziyou Gao

Regenerative braking is an efficient energy saving technology in urban rail system, in which the recovery energy from braking trains is collected by some equipments and

Abstract

Purpose

Regenerative braking is an efficient energy saving technology in urban rail system, in which the recovery energy from braking trains is collected by some equipments and released to accelerating trains when needed. However, the high cost and low lifetime of storage devices prevent the widespread use of this technology. The purpose of this paper is to conduct thorough cost-benefit analysis to facilitate China’s urban rail companies to make decisions on the use of such technology.

Design/methodology/approach

To evaluate the benefit from regenerative energy storage, the authors formulate an improved integrated scheduling and speed control model to calculate the net energy consumption associated with different energy recovery rates and then define the benefit as the amount of energy saving arising from the usage of storage equipments. With the frequent charge/discharge operations on storage equipments, the energy recovery rate generally decreases which lowers the benefit, but the maintenance cost increases. By trading-off benefit and cost, the authors derive the optimal scrapping time, the maximum profit and the profitability condition for storage devices.

Findings

Simulation studies based on the Beijing Metro Yizhuang Line of China are given. The results show that compared with the current timetable and speed profile, the integrated scheduling and speed control approach with energy recovery rate of 0.5 can reduce the net energy consumption by 12.69 per cent; the net energy consumption can be well approximated as a linear function of energy recovery rate; and the maximum profit and the optimal scrapping time on regenerative energy storage devices are both positively related to the electricity price. The allowance proportion and the number of service trains such that busy lines with higher electricity price or allowance proportion have advantages to use the regenerative energy storage devices.

Research limitations/implications

In this work, a linear energy recovery rate and a linear maintenance cost are used in the cost-benefit analysis process. In future research, the more accurate expressions on energy recovery rate and maintenance cost should be considered if more data on recovery rate and maintenance cost can be gathered.

Originality/value

The main values of this paper are to develop the integrated optimization approaches for train scheduling and speed control and, on this basis, make thorough cost-benefit analysis for regenerative energy storage to improve the operations management of urban rail transit.

Details

Chinese Management Studies, vol. 11 no. 1
Type: Research Article
ISSN: 1750-614X

Keywords

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Book part

Irina Farquhar and Alan Sorkin

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized…

Abstract

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Details

The Value of Innovation: Impact on Health, Life Quality, Safety, and Regulatory Research
Type: Book
ISBN: 978-1-84950-551-2

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Article

S.H. Chung, Ying Kei Tse and T.M. Choi

The purpose of this paper is to carry out a comprehensive review for state-of-the-art works in disruption risk management of express logistics mainly supported by…

Abstract

Purpose

The purpose of this paper is to carry out a comprehensive review for state-of-the-art works in disruption risk management of express logistics mainly supported by air-transportation. The authors aim to suggest some new research directions and insights for express logistics practitioners to develop more robust planning in air-transportation.

Design/methodology/approach

The authors mainly confined the research to papers published over the last two decades. The search process was conducted in two dimensions: horizontal and vertical. In the horizontal dimension, attention was paid to the evolution of disruption management across the timeline. In the vertical dimension, different foci and strategies of disruption management are employed to distinguish each article. Three keywords were used in the full text query: “Disruption management”, “Air transportation”, and “Airline Operations” in all database searches listed above. Duplications due to database overlap, articles other than those from academic journals, and papers in languages other than English were discarded.

Findings

A total of 98 articles were studied. The authors categorized the papers into two broad categories: Reactive Recovery, and Proactive Planning. In addition, based on the problem characteristics and their application scenarios, a total of 11 sub-categories in reactive recovery and nine sub-categories in proactive planning were further identified. From the analysis, the authors identified some new categories in the air-transportation recovery. In addition, by analyzing the papers in robust planning, according to the problem characteristics and the state-of-the-art research in recovery problems, the authors proposed four new research directions to enhance the reliability and robustness of air-transportation express logistics.

Research limitations/implications

This study provided a comprehensive and feasible taxonomy of disruption risk management. The classification scheme was based on the problem characteristics and the application scenarios, rather than the algorithms. One advantage of this scheme is that it enables an in-depth classification of the problem, that is, sub-categories of each class can be revealed, which provides a much wider and clearer horizon to the scientific progress in this area. This helps researchers to reveal the problem’s nature and to identify the future directions more systematically. The suggestions for future research directions also point out some critical research gaps and opportunities.

Practical implications

This study summarized various reasons which account for the disruption in air-transportation. In addition, the authors suggested various considerations for express logistics practitioners to enhance logistics network reliability and efficiency.

Originality/value

There are various classification schemes in the literature to categorize disruption management. Using different algorithms (e.g. exact algorithm, heuristics, meta-heuristics) and distinct characteristics of the problem elements (e.g. aircraft, crew, passengers, etc.) are the most common schemes in previous efforts to produce a disruption management classification scheme. However, the authors herein attempted to focus on the problem nature and the application perspective of disruption management. The classification scheme is hence novel and significant.

Details

Industrial Management & Data Systems, vol. 115 no. 8
Type: Research Article
ISSN: 0263-5577

Keywords

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Article

Isil Yazar, Emre Kiyak, Fikret Caliskan and T. Hikmet Karakoc

This paper aims to present a nonlinear mathematical model of a small-scale turbojet aeroengine and also a speed controller design that is conducted for the constructed…

Abstract

Purpose

This paper aims to present a nonlinear mathematical model of a small-scale turbojet aeroengine and also a speed controller design that is conducted for the constructed nonlinear mathematical model.

Design/methodology/approach

In the nonlinear mathematical model of the turbojet engine, temperature, rotational speed, mass flow, pressure and other parameters are generated using thermodynamic equations (e.g. mass, energy and momentum conservation laws) and some algebraic equations. In calculation of the performance parameters, adaptive neuro fuzzy inference system (ANFIS) method is preferred in related components. All calculated values from the mathematical model are then compared with the cycle data of the turbojet engine. Because of the single variable control need and effect of noise factor, modified proportional–integral–derivative (PID) controller is treated for speed control. For whole operation envelope, various PID structures are designed individually, according to the operating points. These controller structures are then combined via gain-scheduling approach and integrated to the nonlinear engine model. Simulations are performed on MATLAB/Simulink environment for design and off-design operating points between idle to maximum thrust levels.

Findings

The cascade structure (proposed nonlinear engine aero-thermal model and speed controller) is simulated and tested at various operating points of the engine and for different transient conditions. Simulation results show that the transitions between the operating points are found successfully. Furthermore, the controller is effective for steady-state load changes. It is suggested to be used in real-time engine applications.

Research limitations/implications

Because of limited data, only speed control is treated and simulated.

Practical implications

It can be used as an application in the industry easily.

Originality/value

First point of novelty in the paper is in calculation of the performance parameters of compressor and turbine components. ANFIS method is preferred to predict performance parameters in related components. Second novelty in the paper can be seen in speed controller design part. Because of the single variable control need and effect of noise factor, modified PID is treated.

Details

Aircraft Engineering and Aerospace Technology, vol. 90 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

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Article

Yunpeng Zhang and Haibin Duan

The purpose of this paper is to develop a directional and roll control system for unmanned combat air vehicle (UCAV) automatic takeoff roll, with the objective of keeping…

Abstract

Purpose

The purpose of this paper is to develop a directional and roll control system for unmanned combat air vehicle (UCAV) automatic takeoff roll, with the objective of keeping the UCAV along the runway centerline and keeping the wings level, especially when there is a crosswind.

Design/methodology/approach

The nonlinear model of the UCAV during takeoff roll is established. The model is linearized about the lateral‐directional equilibrium point at different forward speeds. The approximate directional model and roll model are extracted using time‐scale decomposition technique. Then the directional control law and roll control law are developed using gain scheduling approach. Nose wheel steering, differential brake and rudder are used as the primary directional control device at low, medium and high speeds, respectively, according to both the qualitative and quantitative analysis of their control effectiveness at different speeds. A priority matrix is developed to determine the secondary control device which is used if the primary control device fails, thus the directional control system can have a certain degree of fault tolerance.

Findings

This work developed the directional control law and roll control law by using gain scheduling approach. Experimental results verified that the developed directional and roll control system has high robustness and satisfactory fault tolerance: it can guarantee a safe takeoff under a 50 ft/sec crosswind, even if one directional control device fails, which satisfies the relevant criteria in MIL‐HDBK‐1797.

Practical implications

The directional and roll control system developed can be easily applied to practice and can steer the UCAV during takeoff roll safely, which will considerably increase the autonomy of the UCAV.

Originality/value

The paper shows how time‐scale decomposition technique is employed to extract the approximate directional model and roll model, which simplifies model analysis and control law design. A fault‐tolerant directional control system is designed to improve safety during takeoff.

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Article

Zhixiang Chen and Li Li

The purpose of this paper is to study the information support technologies of integrated production planning control for OEM (original equipment manufacturer) driven…

Abstract

Purpose

The purpose of this paper is to study the information support technologies of integrated production planning control for OEM (original equipment manufacturer) driven networked manufacturing systems, and offer implications to firms for implementing networked manufacturing.

Design/methodology/approach

OEM driven networked manufacturing and its operations modes and support technologies are first discussed. Then, integration framework of production planning and control is proposed and relative technologies are discussed. Finally, a case of the application of information support technologies in networked manufacturing is illustrated.

Findings

Both theory analysis and case experience show that information integration and sharing are critical for effective operations of OEM driven networked manufacturing and an integrated production planning and control system can benefit firms for successfully operating a networked manufacturing system.

Practical implications

It is valuable to develop and apply integrated production planning and control systems in OEM driven networked manufacturing, Firms should pay more attention to information sharing and communication with partners and utilize advanced information technologies to synchronize the operations of partners.

Originality/value

Integration framework of production planning and control proposed in this paper has originality and the technology strategies are also practical. Managerial ideas, technology framework and application strategies of integrated production planning and control are helpful for firms to implement OEM driven networked manufacturing.

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Article

Editorial This special issue of Industrial Management & Data Systems is a huge departure from our usual journal/ monograph style. This is an additional issue to the year's…

Abstract

Editorial This special issue of Industrial Management & Data Systems is a huge departure from our usual journal/ monograph style. This is an additional issue to the year's volume — a bonus in fact.

Details

Industrial Management & Data Systems, vol. 92 no. 5
Type: Research Article
ISSN: 0263-5577

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Article

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…

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

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Article

This aircraft, or more exactly this integrated weapons system, is undoubtedly of major importance to both the British aircraft industry and the Royal Air Force. It is…

Abstract

This aircraft, or more exactly this integrated weapons system, is undoubtedly of major importance to both the British aircraft industry and the Royal Air Force. It is beyond question the most exacting project which the British industry has undertaken and as such has demanded adoption of the latest techniques, materials, equipment and management procedures as well as pursuit of research and development programmes on an unprecedented scale. In terms of air power, this system represents a substantial advance on any comparable aircraft or system currently in service and will give the Royal Air Force a strike and reconnaissance capability at high and low level which is possibly unmatched by any other air force in the world. The design philosophy of the TSR‐2 as it applies to an aircraft designed primarily for the high‐speed, low‐level strike/reconnaissance role was described in detail in the December 1963 issue of Aircraft Engineering (Ref. 1) but since that initial appraisal of the TSR‐2 was written some eleven months ago, there has been a gradual release of further information concerning the aircraft, its systems, power plant and equipment. It is the purpose of this article to bring the story up to date in that particular context, although it should be emphasized that the TSR‐2 is still subject to the strictest security embargo and it will be many years before a detailed study of the complete weapons system can be published. It is not intended to cover the same ground as the earlier article (Ref. 1) attempted but, before proceeding to detailed consideration of the systems, a brief overall description of the aircraft is given for the sake of completeness.

Details

Aircraft Engineering and Aerospace Technology, vol. 36 no. 11
Type: Research Article
ISSN: 0002-2667

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Article

David Ray, John Gattorna and Mike Allen

Preface The functions of business divide into several areas and the general focus of this book is on one of the most important although least understood of…

Abstract

Preface The functions of business divide into several areas and the general focus of this book is on one of the most important although least understood of these—DISTRIBUTION. The particular focus is on reviewing current practice in distribution costing and on attempting to push the frontiers back a little by suggesting some new approaches to overcome previously defined shortcomings.

Details

International Journal of Physical Distribution & Materials Management, vol. 10 no. 5/6
Type: Research Article
ISSN: 0269-8218

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