bluuebunny/crossref_metadata_2025 huggingface dataset:
Root cause analysis support for quality improvement in electronics manufacturing
Authors: Huertas‐Quintero L.A.M. , Conway P.P. , Segura‐Velandia D.M. , West A.A.
Published: February 2011

Purpose

The purpose of this paper is to propose a new software tool to support design for quality (DfQ) in the electronics manufacturing sector where quality and reliability are critical.

Design/methodology/approach

An integrated modelling framework that enables complete and realistic representations of manufacturing systems is proposed. A software tool, developed based on this framework, offers two modules to support DfQ: simulation and root cause analysis. This paper focuses on the latter.

Findings

Integrated models enable tracing back effects to their root causes. Software tools based on these, kind of models can provide support in finding and eliminating the cause of a particular effect. This capability can be used to perform DfQ in an effective and accurate way.

Research limitations/implications

The approach proposed strongly depends on the quality models within the integrated modelling framework. The models currently available are little and simplified. Future work includes the enrichment of the software by developing and more quality models.

Practical implications

The adoption of the proposed approach in an industrial context requires formalised information to fulfil the data required by the integrated modelling framework.

Originality/value

The main contribution of the paper is the integrated modelling framework definition and its implementation in the form of a software tool. The adoption of this tool in printed circuit assembly companies can support the solution of real quality problems and consequently, help to optimise manufacturing systems in the domain.
A practical method for measuring product maintainability in a virtual environment
Authors: Yu Haiquan , Peng Gaoliang , Liu Wenjian
Published: February 2011

Purpose

As an important product characteristic, maintainability is recognized as a highly significant factor in the economic success of engineering systems and products. Based on virtual reality technology, this paper aims to create an intuitive, immersive and interactive environment for product maintenance. In order to analyze and evaluate the product maintainability in a virtual maintenance environment, fuzzy comprehensive evaluation is used. At the early design stage, maintainability influencing factors are analyzed and the whole maintainability evaluation of the product is given by using fuzzy comprehensive evaluation method in virtual maintenance environment.

Design/methodology/approach

The paper provides a fuzzy comprehensive evaluation method for product maintainability evaluation in virtual environment.

Findings

Fuzzy comprehensive evaluation is used to evaluate product maintainability in virtual environment, and the application of virtual maintainability system is expanded.

Originality/value

According to maintainability requirement, the maintainability index set is built in this paper, and fuzzy comprehensive evaluation method is used to evaluate product maintainability in virtual maintenance environment at stage of early design.
A systems approach in the evaluation and comparison of engineering services applied in facilities management
Authors: Halim Tony , Muthusamy Kanesan , Yong Chia Sie , Wei Lam Shao
Published: February 2011

Purpose

This paper aims to be a balance of mixed management and engineering concepts that aims to fuse classical engineering methodologies into a systems engineering framework to assess and compare systematically and comprehensively services rendered by engineering systems.

Design/methodology/approach

An auditing framework is developed to assess the performance of engineering services in the context of engineering services found within a facility. As a result of a system heterogeneity factor, an approach to remove this confounding issue is developed to provide a different insight into the performance of engineering services.

Findings

The output of the audit exercise serves as an input to the second methodology, direct age‐adjusted failure, which overcomes systems attributes confounding issues when comparison is made between different systems populations of the same class type. This method allows management to identify areas in which extra resources are needed to improve maintenance performance.

Practical implications

The proposed standardization technique, which can be applied to system attributes other than age, overcomes the systems heterogeneity issue between localities. This research work is positioned in the context of building engineering services, as they are the most important in terms of socio‐economical impact. A case study based on an actual facilities assessment in Singapore is used to demonstrate the usefulness of such an integrated systems approach.

Originality/value

This paper presents a qualitative‐quantitative assessment framework that consists of two major methodologies to help in identifying and prioritising engineering system services in order to allocate limited resources to the appropriate engineering service so as to improve its performance.
On the modeling of shear bands formation in J2materials with damage evolution
Authors: D'hers Sebastian , Dvorkin Eduardo N.
Published: February 2011

Purpose

The purpose of this paper is to model the strain localization in J2materials with damage evolution using embedded strong discontinuity modes.

Design/methodology/approach

In this procedure, an heuristic bandwidth scale is adopted to model the damage evolution in the shear bands. The bifurcation triggering conditions and band growth directions are studied for these materials.

Findings

The resulting formulation does not require a specific mesh refinement to model a localization, provides mesh independent results also insensitive to element distortions and allows calibration of the model response using experimental data. The formulation capability is shown embedding the strong discontinuity modes into quadrilateral and higher order elements.

Originality/value

The work described in this paper extends the use of strong discontinuity modes to materials with damage evolution.
Experimental and numerical analysis of blade channel vortices in a Francis turbine runner
Authors: Yexiang Xiao , Zhengwei Wang , Zongguo Yan
Published: February 2011

Purpose

The purpose of this paper is to investigate, experimentally and numerically, the pressure pulse characteristics and unsteady flow behavior in a Francis turbine runner for moderate flow heads. The pressure pulses in the runner blade passage were predicted numerically for both moderate and high heads. The calculations were used to partition the turbine operating regions and to clarify the various for the unsteady flow behavior, especially the blade channel vortex in the runner.

Design/methodology/approach

Experimental and numerical analyses of pressure pulse characteristics at moderate flow heads in a Francis turbine runner were then extended to high heads through numerical modeling with 3D unsteady numerical simulations performed for a number of operating conditions. The unsteady Reynolds‐averaged Navier‐Stokes equations with the k‐ω‐based shear stress transport turbulence model were used to model the unsteady flow within the entire flow passage of a Francis turbine.

Findings

The dominate frequency of the predicted pressure pulses at runner inlet agree with the experimental results in the head cover at moderate flow heads. The influence of the blade passing frequency causes the simulated peak‐to‐peak amplitudes in the runner inlet to be larger than in the head cover. The measured and predicted pressure pulses at different positions along the runner are comparable. At the most unstable operating condition of 0.5a0 guide vane opening, the pressure pulses in the runner blade passage are due to the blade channel vortex and the rotor‐stator interference. The predictions show that the frequency of the blade channel vortex is relatively low and it changes with the operating conditions.

Originality/value

The paper describes a study which experimentally and numerically investigated the pressure pulses characteristics in a Francis turbine runner at moderate flow heads. The pulse characteristics and unsteady flow behavior due to the blade channel vortex in the runner at high heads were investigated numerically, with the turbine operating regions then partitioned to identify safe operating regions.
Drivers of change: a contemporary model
Authors: Kirsch Christina , Chelliah John , Parry Warren
Published: February 2011

Purpose

This paper introduces a contemporary model developed by a Sydney‐based consulting firm, ChangeTracking Research. The model was developed through an initial survey of 146 companies based in 27 countries.

Design/methodology/approach

The authors present a change development model which uses Hofstede's work as a foundation for understanding cross‐cultural differences in organizations from across the world and how that affects change management in these cultures. The model is informed by initial surveys of employees from 27 nationalities in 146 companies working in a variety of industries.

Findings

The paper presents a model that identifies six key drivers arising from different cultural dimensions that determine success in change management projects.

Practical implications

The model developed in this paper introduces new knowledge of the cross‐cultural dynamics in change management projects which would prove useful to change managers throughout the world.

Originality/value

The paper presents a unique model that presents six key drivers that determine the success of change management. A subset of clusters under each driver presents an in‐depth understanding of the critical issues to be recognized and managed in differing cultural contexts.
How platform leaders win
Authors: Hidding Gezinus J. , Williams Jeff , Sviokla John J.
Published: February 2011

Purpose

To study successful strategies in platform industries, which are IT products that enable (a network of) users to communicate with each other, and that, consequently, exhibit network effects.

Design/methodology/approach

The authors studied 15 platform industries, including their first‐mover, early entrants and current leaders. Also studied were historical documents, for example to find the time of market entry.

Findings

Unlike traditional products (e.g. consumer products), platforms evolve over time by technically integrating separate platforms (“embrace and extend”). Two key patterns were found among platform leaders: follower advantage and staircase strategies. While follower advantage is also prevalent in traditional industries, staircase strategies are not. Complementary resources (i.e. resources the firm possesses outside of the product in question, for example R&D skills or customer relations) did not explain why the current leaders won.

Research limitations/implications

First‐mover advantage was largely illusionary and follower advantage prevalent. Some leaders of platform industries entered the industry early and some entered late, but it is not clear why a particular entry timing was successful in one platform industry but not in another. The authors cannot (yet) predict how a platform industry evolves, particularly in the presence of network effects.

Practice implications

To become the leader in a platform industry, do not become the first mover, but enter some time afterwards, and manage the “embrace and extend” platform evolution using staircase strategies.

Originality/ value

This study analyzed a sample of 15 platform industries, i.e. more than a few case studies.
Testing the weak‐form efficiency in African stock markets
Authors: Ntim Collins G. , Opong Kwaku K. , Danbolt Jo , Senyo Dewotor Frank
Published: February 2011

Purpose

The purpose of this paper is to investigate and compare the weak‐form efficiency of a set of 24 African continent‐wide stock price indices and those of eight individual African national stock price indices.

Design/methodology/approach

Variance‐ratio tests based on ranks and signs were used to examine the weak‐form efficiency of the 32 stock price indices investigated.

Findings

On average, it was found that irrespective of the test employed, the returns of all the 24 African continent‐wide stock price indices examined in the study are less non‐normally distributed compared to the eight individual national stock price indices examined. The authors also report evidence of the African continent‐wide stock price indices having significantly better weak‐form informational efficiency than their national counterparts.

Practical implications

The policy implication of this evidence is that the African equity price discovery process can be significantly improved if African stock markets integrate their operations. Economically, this may contribute to improved liquidity and more efficient allocation of capital, which in turn can be expected to have a positive impact on economic growth.

Originality/value

The paper makes two major contributions to the extant literature. First, it offers for the first time a comparative analysis of the informational efficiencies of a sample of national stock price indices as against African continent‐wide stock price indices. Second, there is no prior evidence as to whether African stock markets can improve their informational efficiencies by integrating their operations. The paper fills this gap by demonstrating that the African equity price formation process can be improved if African stock markets integrate their operations.
Measuring volatility persistence and long memory in the presence of structural breaks
Authors: McMillan David , Thupayagale Pako
Published: February 2011

Purpose

The purpose of this paper is to estimate volatility in African stock markets (ASMs), taking account of periodic level shifts in the mean level of volatility, where the regime shifts are determined endogenously.

Design/methodology/approach

Volatility estimates are incorporated into standard volatility models to assess the impact of structural breaks on volatility persistence, long memory and forecasting performance for ASMs.

Findings

The results presented here indeed suggest that persistence and long memory in volatility are overestimated when regime shifts are not accounted for. In particular, application of breakpoint tests and a moving average procedure suggest that unconditional volatility displays substantial time variation.

Practical implications

A modification of the standard generalised autoregressive conditional heteroscedasticity model to allow for time variation in the unconditional variance generates improved volatility forecasting performance for some African markets.

Originality/value

This paper describes one of the first studies to incorporate endogenously determined regime shifts into volatility estimates and assess the impact of structural breaks on volatility persistence, long memory and forecasting performance for ASMs.
The rare event risk in African emerging stock markets
Authors: Tolikas Konstantinos
Published: February 2011

Purpose

The purpose of this paper is to investigate the asymptotic distribution of the extreme daily stock returns in African stock markets over the period 1996‐2007 and examine the implications for downside risk measurement.

Design/methodology/approach

Extreme value theory methods are used to model adequately the extreme minimum daily returns in a number of African emerging stock markets.

Findings

The empirical results indicate that the generalised logistic distribution best fitted the empirical data over the period of study.

Practical implications

Using the generalised extreme value and normal distributions for risk assessment could lead to an underestimation of the likelihood of extreme share price declines which could potentially lead to inadequate protection against catastrophic losses.

Originality/value

To the best of the author's knowledge, this is the first study to examine the lower tail distribution of daily returns for African emerging stock markets.
Solution of Raman fiber amplifier equations using MATLAB BVP solvers
Authors: Serdar Gokhan Fikri , Yilmaz Gunes
Published: February 2011

Purpose

The purpose of this paper is to demonstrate an effective and robust numerical solution for Raman fiber amplifier (RFA) equations which have no explicit solution. MATLAB BVP solvers are addressed for the solution.

Design/methodology/approach

The continuation method proposed for the solution of RFA equations using MATLAB BVP solvers is explained. Scripts for improving the power values at the boundaries with continuation, extending fiber length with continuation and calculation of the analytical partial derivatives using the MATLAB Symbolic toolbox are introduced. Comparisons among the different MATLAB BVP solvers have been made. Using the continuation method, signal evolutions for different kinds of RFA amplifier configurations are plotted.

Findings

The paper finds that MATLAB BVP solver with the continuation method can be used in the design of various kinds of RFAs for high powers/long gain fiber spans.

Research limitations/implications

The paper will assist the fiber optic research community who suffer from two or more point boundary‐value problems. Moreover, the stiffness of the signal evolution which is faced with high pump powers and/or long fiber lengths can be solved with continuation. This superiority of the solver can be used to overcome any stiff changes of the signals for future studies.

Practical implications

The increased research interests and practical demands for RFAs have been calling for reasonable and efficient means for the performance evaluation of RFAs before the real amplifiers are fabricated. The solution method presented in this paper will be an efficient means for the solution of this issue.

Originality/value

MATLAB BVP solvers have been proven to be effective for the numerical solution of RFAs with multiple pumps and signal waves. Using the continuation method, in a distributed RFA with ten pump sources, 2,400 mW total input pump power is achieved. The improvement of the total power is about 1.4 times compared with those of the previously reported methods. Using the MATLAB BVP solvers, total power/fiber span can be improved further using the continuation process with the cost of computational time. This is a notable and promising improvement from a RFA designer's point of view.
A DWT‐based approach for detection of interturn faults in power transformers
Authors: Behjat Vahid , Vahedi Abolfazl
Published: February 2011

Purpose

Interturn winding faults, one of the most important causes of power transformers failures, cannot be detected by existing detection methods until they develop into high‐level faults with more severe damage to the transformer. The purpose of this paper is to describe development of a new discrete wavelet transform (DWT) based approach for detection of winding interturn faults.

Design/methodology/approach

The following approach was accomplished for development of the proposed fault detection method in this study. The DWT was first applied to decompose the terminal current signals of a transformer, which in turn were obtained from simulations using a finite elements method model of the transformer, into a series of wavelet components. Based on the characteristic features associated with interturn faults extracted from the decomposed waveforms of the terminal currents, a detection scheme was developed. An experimental setup was used to validate the proposed detection method.

Findings

The results of this study demonstrate the efficacy of DWT applied on terminal currents of the transformer to identify interturn faults on the windings well before such faults lead to a catastrophic failure. It is believed that, based on the present findings, there definitely exists scope for improving interturn fault diagnosis with wavelet transform.

Research limitations/implications

Performing more detailed studies to find all relevant characteristics of the wavelet transform in this application, identifying the location of the faulted turns along winding, applying the method for indicating early stages of turn insulation deterioration and evaluating other type of wavelets for this application would be some future directions of this research.

Practical implications

With the proposed method, it is becoming possible to detect early signs of the fault occurrence, so that the necessary corrective actions can be taken to prevent long‐lasting outages and reduce down times of the faulty power transformer. The method will be particularly useful as a complement for the classical protection devices of the power transformers.

Originality/value

Some recent studies have been carried out regarding the application of DWT for discrimination between an internal fault and other disturbances such as magnetizing inrush and external faults. This paper extends those studies for the detection of interturn faults using more quantitative and qualitative characteristics features.
A novel PSO‐based technique for optimal design of protective current transformers
Authors: Rashtchi Vahid , Bagheri Amir , Shabani Arash , Fazli Saeed
Published: February 2011

Purpose

The purpose of this paper is to present a new approach for the optimal design of protective current transformers (CTs). The proposed technique is applied to the design of typical CTs and results are compared with traditional CT design method and genetic algorithm optimization algorithm.

Design/methodology/approach

The aim of CT design is to make current measurements more accurately, particularly for the high fault currents which arise in short circuits, and more efficient CT in terms of both size and cost. The present work formulates these objectives as an optimization problem to be solved by particle swarm optimization.

Findings

Simulation results demonstrate the effectiveness of this technique in optimizing the CT design parameters. The designed CTs have smaller measurement errors compared to standard values and respond well to high fault currents. Manufacturing costs have also been reduced.

Originality/value

In addition to improved efficiency, the benefits of this method are its treatment of CT design in terms of an equivalent circuit and design parameters. The proposed algorithm also extends the linear operation area of the CT and guarantees its good response to high fault currents that may occur in power systems.
Flexible approximation schemes with numerical and semi‐analytical bases
Authors: Dai Jianhua , Pinheiro Helder , Webb Jonathan P. , Tsukerman Igor
Published: February 2011

Purpose

The purpose of this paper is to extend the generalized finite‐difference calculus of flexible local approximation methods (FLAME) to problems where local analytical solutions are unavailable.

Design/methodology/approach

FLAME uses accurate local approximations of the solution to generate difference schemes with small consistency errors. When local analytical approximations are too complicated, semi‐analytical or numerical ones can be used instead. In the paper, this strategy is applied to electrostatic multi‐particle simulations and to electromagnetic wave propagation and scattering. The FLAME basis is constructed by solving small local finite‐element problems or, alternatively, by a local multipole‐multicenter expansion. As yet another alternative, adaptive FLAME is applied to problems of wave propagation in electromagnetic (photonic) crystals.

Findings

Numerical examples demonstrate the high rate of convergence of new five‐ and nine‐point schemes in 2D and seven‐ and 19‐point schemes in 3D. The accuracy of FLAME is much higher than that of the standard FD scheme. This paves the way for solving problems with a large number of particles on relatively coarse grids. FLAME with numerical bases has particular advantages for the multi‐particle model of a random or quasi‐random medium.

Research limitations/implications

Irregular stencils produced by local refinement may adversely affect the accuracy. This drawback could be rectified by least squares FLAME, where the number of stencil nodes can be much greater than the number of basis functions, making the method more robust and less sensitive to the irregularities of the stencils.

Originality/value

Previous applications of FLAME were limited to purely analytical basis functions. The present paper shows that numerical bases can be successfully used in FLAME when analytical ones are not available.
An iterative method for optimal resolution‐constrained polar quantizer design
Authors: Petković Marko D. , Perić Zoran H. , Jovanović Aleksandra Ž.
Published: February 2011

Purpose

The purpose of this paper is to address the problem of polar quantization optimization. Particularly, the aim is to find the method for the optimal resolution‐constrained polar quantizer design.

Design/methodology/approach

The new iterative algorithm for determination of the optimal decision and representation magnitude levels and algorithm for optimization of number of phase cells within each magnitude level, is proposed.

Findings

At high rates, the new optimal polar quantizer outperforms the optimal polar compander for 0.2 dB, while the more significant gain should be expected at lower rates. In this paper, in order to enable practical implementation of quantizer model, algorithm which transforms real values for the optimal numbers of phase cells within magnitude levels into integer ones is also proposed. Moreover, the approximate closed form of signal‐to‐quantization ratio is derived.

Practical implications

Since circularly symmetric sources and complex presentation of signals arise in numerous applications, it can be concluded that the usage area of the suggested proposal is very wide (audio coding, image coding, spectral phase coding, synthetic aperture radars systems, coding of the discrete Fourier transform).

Originality/value

It should be emphasized that in contrast to earlier work, where models have been designed under high‐rate assumption, the obtained nonuniform unrestricted polar quantizer is optimal for all rates.
A novel reactive navigation strategy for mobile robots based on chaotic exploration and TTM self‐construction
Authors: Yu Xiaolei , Zhao Zhimin
Published: February 2011

Purpose

The purpose of this paper is to present a novel method for integrating of chaotic exploration and thinning‐based topological mapping to deal with the “traverse targets and return” problem applied for robot navigation in unknown environments. This new strategy can guarantee the robot stronger ability of exploring unknown environments, as well as recording and selecting optimal trajectory to return.

Design/methodology/approach

The chaotic dynamic evolution of controlled multi‐scroll system is linked to the multi‐sensory perception and reactive behaviors of a mobile robot. The thinning‐based topological map (TTM), as the contextual layer of the cognitive system, is adopted to achieve the environmental recording in the process of robot exploration and navigation. Once the robot arrives at the terminal target via avoiding all the obstacles, the TTM has been built in real time. Based on the records in the topological map, a short and smooth point‐to‐point path is generated to achieve the exit from target and to move back to the starting point.

Findings

The simulation results confirmed that the proposed solution is suitable to resolve the robot's tasks of obstacle avoidance, target retrieving, and return, also has better performance than traditional strategies.

Originality/value

The presented novel method focuses integration of chaotic exploration and TTM self‐construction. The chaotic perception and control technique permits the robot to explore most of the environmental information within the smallest explored area. The introduced topological map, generated by applying a thinning algorithm, guarantees a short and smooth returning trajectory for the robot.
Pointwise completeness and pointwise degeneracy of 2D standard and positive Fornasini‐Marchesini models
Authors: Kaczorek Tadeusz
Published: February 2011

Purpose

The purpose of this paper is to formulate and solve the pointwise completeness and pointwise degeneracy of standard and positive 2D Fornasini‐Marchesini and 2D Roesser models.

Design/methodology/approach

A procedure is proposed for investigation of the pointwise completeness and pointwise degeneracy of 2D standard and positive Fornasini‐Marchesini and Roesser models.

Findings

Necessary and sufficient conditions for pointwise completeness and pointwise degeneracy of standard and positive Fornasini‐Marchesini and Roesser models are established.

Originality/value

The paper proposes a method for investigation of the pointwise completeness and pointwise degeneracy of the standard and positive Fornasini‐Marchesini and Roesser models.
Determining degrees of freedom for eccentricity fault in SRM based on nonlinear static torque function
Authors: Torkaman Hossein , Afjei Ebrahim
Published: February 2011

Purpose

The purpose of this paper is to determine the degrees of freedom (DOF) for eccentricity fault in switched reluctance motor (SRM) based on nonlinear static torque function to minimize torque ripple for maximum performance in motoring operation.

Design/methodology/approach

An algorithm based on nonlinear torque function versus rotor position and percent of rotor eccentricity for the SRM operation is introduced. This algorithm enables accurate determination of different modes of motor operations namely, healthy and faulty conditions. In this approach, SRM is first analyzed by a 3D finite element method for estimation of nonlinear torque function and then the function is approximated by least square, cubic spline and piecewise cubic Hermitian methods. The minimization is performed by random search method and genetic algorithm.

Findings

A new procedure for computing the DOF of eccentricity in SRM based on nonlinear torque function is proposed and analyzed. It computes the legal intervals for the radial airgap length as well as the regions of the motor operation under different conditions. The functionability and the feasibility of this algorithm is illustrated by employing it on a three‐phase 6/4 SRM.

Practical implications

The proposed method and its results can improve the motor control while the implementation is simple and practical. The proposed method can be used for other motors as well.

Originality/value

The boundary of motor operation under fault must be calculated to attain smooth control on motor to achieve high performance expected from the machine. To the best knowledge of the authors, this is the first time such a study has been conducted on SRM.
Speed sensorless induction motor drive with motor choke and predictive control
Authors: Guzinski Jaroslaw , Abu‐Rub Haitham
Published: February 2011

Purpose

The purpose of this paper is to present a complete solution for speed sensorless AC drive with voltage source inverter, induction machine, and motor choke. Major problems with adjustable speed drives are underlined and the use of motor choke is justified. An AC drive with motor choke can work only if specific modifications in the control algorithms are done.

Design/methodology/approach

The goal of the paper is to present new nonlinear vector control method for induction motor drive. In the control system, the presence of motor choke is taken into account. The choke changes the structure of the predictive controller and state observer. The new concept of integrating the predictive controller with electromagnetic forces observer is presented. The paper presents theoretical description of the system as well the simulation and experimental verification.

Findings

The paper shows that the suggested decoupled AC drive control system is operating better than a system without decoupling. The system with motor choke requires modifications in the current controller and observer system. With omitting the motor choke a speed sensorless drive cannot work properly.

Practical implications

The solution is oriented for industrial applications because in numerous industrial dives the motor choke is utilized. However, with motor choke many sophisticated control algorithms cannot work properly. The concept presented in the paper solves such practical problems.

Originality/value

The paper presents a completely new decoupled field‐oriented control system with load angle controller, predictive current controller and state observer for AC drive with motor choke.
Modeling and optimal control of variable reluctance stepper motor
Authors: Stepien Slawomir , Bernat Jakub
Published: February 2011

Purpose

The purpose of this paper is to present a method of modeling the variable reluctance stepper motor using the time‐stepping finite element technique. The proposed model is used to obtain the optimal control law for the input circuit solving the linear‐quadratic problem.

Design/methodology/approach

A strongly coupled field‐circuit model of the stepper motor is presented. Also, the method of the optimal control that minimizes the power loss in the motor windings is proposed.

Findings

The proposed optimal control method can be applied to the electrical machines connected to the electronic converters. Calculated control signals may be used to obtain the optimal waveforms of the input voltages at each phase of the analyzed machine.

Originality/value

The paper examines the application of the presented control method to minimize the power loss in the stator windings of the four‐phased variable reluctance stepper motor.
Hierarchical synthesis system with hybrid DLO‐MOGA optimization
Authors: Gerard Scanlan Anthony , Halton Mark Keith
Published: February 2011

Purpose

The purpose of this paper is to present a hierarchical circuit synthesis system with a hybrid deterministic local optimization – multi‐objective genetic algorithm (DLO‐MOGA) optimization scheme for system‐level synthesis.

Design/methodology/approach

The use of a local optimization with a deterministic algorithm based on linear equations which is computationally efficient and improves the feasibility of designs, allows reduction in the number of MOGA generations required to achieve convergence.

Findings

This approach reduces the total number of simulation iterations required for optimization. Reduction in run time enables use of full transistor‐level models for simulation of critical system‐level sub‐blocks. Consequently, for system‐level synthesis, simulation accuracy is maintained. The approach is demonstrated for the design of pipeline analog‐to‐digital converters on a 0.35 μm process.

Originality/value

The use of a hybrid DLO‐MOGA optimization approach is a new approach to improve hierarchical circuit synthesis time while preserving accuracy.
Comparison of first‐ and second‐order 2D finite element models for calculating AC loss in high temperature superconductor coated conductors
Authors: Ainslie Mark D. , Flack Tim J. , Hong Zhiyong , Coombs Tim A.
Published: February 2011

Purpose

The purpose of the paper is to provide a comparison of first‐ and second‐order two dimensional finite element models for evaluating the electromagnetic properties and calculating AC loss in high‐temperature superconductor (HTS) coated conductors.

Design/methodology/approach

The models are based on the two‐dimensional (2D) H formulation, which is based on directly solving the magnetic field components in 2D. Two models – one with a minimum symmetric triangular mesh and one with a single‐layer square mesh – are compared based on different types of mesh elements: first‐order (Lagrange – linear) and second‐order (Lagrange – quadratic) mesh elements, and edge elements.

Findings

The number and type of mesh elements are critically important to obtain the minimum level of discretization to achieve accurate results. Artificially increasing the superconductor layer and choosing a minimum symmetric mesh with triangular edge elements can provide a sufficiently accurate estimation of the hysteretic superconductor loss for a transport current.

Originality/value

This paper describes how the selection of mesh type and number of elements affects the computation speed and convergence properties of the finite element model using two different types of meshing. It offers an insight into the different factors modelers must consider when modeling HTS coated conductors and the methods that may be applied when extending the model to complex device geometries, such as wound coils.
Geometrical information coded in Maxwell's equations: a review
Authors: Baldomir Daniel , Pereiro Manuel , Arias Juan
Published: February 2011

Purpose

The purpose of this paper is to show how the geometrical information of Maxwell's equations is coded into the constitutive equations.

Design/methodology/approach

The Maxwell's equations have been written with the tensorial algebra into a three‐dimensional Euclidean space and compared with the usual four‐dimensional relativistic approach.

Findings

This simple geometry allows the finding of the relativistic information coded on the electric and magnetic fields, showing that they are not independent as relativity affirm obtaining their transformation for a moving inertial observer.

Originality/value

The main value of the paper is to present a simple mathematical tool which enables the engineers or applied physicists to obtain the relativistic transformations of the fields without using four‐dimensional geometries and the more sophisticated mathematical techniques.
The role of channel orientation in B2B technology adoption
Authors: Asare Anthony K. , Brashear Alejandro Thomas G. , Granot Elad , Kashyap Vishal
Published: February 2011

Purpose

The purpose of this paper is to develop an in‐depth understanding of the issues that organizations consider and experience when making the decision to adopt B2B technologies.

Design/methodology/approach

The paper uses a qualitative approach to collect and analyze data. In‐depth interviews were conducted to help generate new themes, and ideas about B2B technology adoption. After the data were collected, the authors used an elaborate multi‐stage process to code, analyze, and interpret the data generated from the interviews.

Findings

The main theme that emerged out of this study is that an organization's response to requests from its trading partner to adopt B2B technologies is highly influenced by its marketing channel orientation. The study identifies three types of marketing channel orientations that can influence a firm's technology adoption decision and demonstrates how each of these orientations influence a firm's responses and attitudes towards B2B technology adoption.

Originality/value

The study is important to practitioners since it helps them recognize the value of understanding their trading partner's channel strategies and orientations as they develop strategies to get their suppliers to adopt B2B technologies. It also contributes to the academic literature by demonstrating the value of a firm's channel strategy orientation, a very important concept that has been ignored in the channels and B2B technology adoption literature.
Bond audit, a method for evaluating business relationships
Authors: Wendelin Robert
Published: February 2011

Purpose

The purpose of this paper is to create an audit method for analyzing and improving business relationships. This is accomplished by specifying bonds on a lower abstraction level than in earlier theory regarding bonds in order to classify the different types of bonds and analyze their strength.

Design/methodology/approach

The findings are based on 14 case studies in seven different industries. The methodology used is systematic and based on the abductive approach. Qualitative interviews were conducted.

Findings

Bonds were found to be important regulators of business relationships in this study. The main finding is that a bond audit can be used as a tool for analyzing business relationships and for consulting activity with the aim of strengthening or weakening business relationships.

Practical implications

By influencing the bonds using bond management, companies can strengthen or weaken the business relationship.

Originality/value

The paper describes an audit method for analyzing business relationships by stringently analyzing all parts of it using the bond‐auditing tool, and thus auditing bonds more specifically than has been done previously.
Towards the next generation of public management
Authors: Almqvist Roland , Catasús Bino , Skoog Matti
Published: February 2011

Purpose

This paper aims to present an empirical case where fundamental changes in the environment have forced an organization to re‐evaluate its management control systems and possibly search for destabilizing supporting routines in order to unlearn the established ways of measuring and controlling within the organization. The problem, however, is that organizational technologies often work in the other direction, i.e. they promote stability in organizational routines. The paper seeks to increase understanding regarding the importance of destabilizing, or, as the authors like to call them, sensebreaking activities within organizations that are present in rapidly changing environments.

Design/methodology/approach

The authors used multiple sources and multiple techniques to collect data; interviews with managers, participation in meetings, and document analysis such as annual reports, pamphlets, speeches and Swedish Armed Forces's (SAF's) web site.

Findings

The study is clearly presented in a design‐oriented way. The benefits, however, are that it illustrates that the available models take for granted that the organization has a mission that is accepted. When the mission is debated, the focus and practice of management control falls into pieces. Also, when the ontology of the organization is debated, flexibility does not suffice. The proposition is that it is through sensebreaking that a reflective position may be held. That is, a position where everything may be questioned and that this questioning never stops.

Originality/value

The study of the SAF could probably be labeled a study of an extreme case. Extreme cases facilitate theory building because the dynamics being examined tend to be more visible than they might be in other contexts. The caveat, however, is that this particular case study risks becoming anecdotal since the SAF is, per definition, one of a kind. The paper's argument, however, is that the SAF acts as an illustration of the limits (and possibilities) of management control theory and how it is framed as a technology in a milieu that is neither relatively stable nor stable, but rather under extraordinary pressure for change.
Implementing the UK Central Government's policy agenda for improved third sector engagement
Authors: Jones Martin , Liddle Joyce
Published: February 2011

Purpose

As many states recognise the need to enter into new relationships with the third sector, strategic commissioning of services has moved up the political agenda. The establishment of the Office of the Third Sector in the UK Cabinet Office heralded a commitment to engage the “voice” and “choice” of third sector organizations in designing, delivering and measuring public service delivery. This paper seeks to report on the findings gathered from a series of workshops and other data collection on public sector commissioning of third sector service delivery, and to highlight some tensions and emerging issues in this policy field.

Design/methodology/approach

Qualitative data from workshops were supplemented with observations, interview data, existing research, and secondary data from a number of government agencies and third sector representative organizations.

Findings

The findings from the workshops and other data collection methods will feed into future design and development of training programmes for public sector and third sector officers. They should also inform the policy debate and enhance understanding of some of the tensions and problems facing practitioners in this policy field.

Originality/value

Little research exists on third sector or public sector commissioning, and this work will be of value to policy makers, practitioners and academics concerned with strategic commissioning. The paper augments existing theory on state and non‐governmental relationships and the contribution of third sector agencies to public service delivery.
Towards a humanitarian logistics knowledge management system
Authors: Tatham Peter , Spens Karen
Published: February 2011

Purpose

The aim of this paper is to offer a conceptual model and an associated taxonomy to support the development of a body of knowledge in support of the logistic response to a natural or man‐made disaster.

Design/methodology/approach

Based on a literature review, the paper outlines the difficulties associated with the logistic response to a disaster, before discussing a generic approach to knowledge management. The literature review is then used to identify two potential models (the Supply‐Chain Operations Reference (SCOR) and the UK Defence Lines of Development (LOD)), which are then further developed and integrated in order to underpin a knowledge taxonomy.

Findings

The paper proposes a model that combines both the SCOR and LOD models into a unified approach as a first step towards the development of a broad‐ranging reference source to support humanitarian logisticians and, thereby, improve the effectiveness and efficiency of the response to future disasters.

Research limitations/implications

As a first step towards the creation of a knowledge taxonomy, this conceptual paper does not attempt to validate the model, but it proposes an approach by which this could be undertaken.

Practical implications

Given the plethora of non‐governmental organizations (NGOs) in the broadest sense of this categorization, and also recognizing the varied nature of their aims, objectives and approaches, the paper pays particular attention to the need to develop a model that can be supported by the NGO community as a whole.

Originality/value

The paper proposes an improved model to support the development of a body of knowledge in support of the logistic response to a natural or man‐made disaster.
Mega fires: can they be managed effectively?
Authors: Maditinos Zissis , Vassiliadis Christos
Published: February 2011

Purpose

The purpose of this paper is to provide a review of mega fire catastrophic phenomena and bring out some useful aspects for more effective pre‐, during and post‐disaster management of mega fires.

Design/methodology/approach

The paper uses two very recent (2007) mega fire cases (Peloponnese – Greece and California – USA) to provide evidence of the magnitude of this kind of disaster and how their impacts can be mitigated if certain management practices are implemented.

Findings

Mega fires are major catastrophic events, with multiple impacts for the communities and areas in which they happen. They are very difficult to manage, mainly owing to their magnitude. However, their negative effects and impacts can be mitigated if pre‐, during, and post‐disaster activities and measures are planned and implemented.

Originality/value

This paper could be useful to practitioners and public service managers that are responsible for the development of fire management policies and management of mega fires situations.