bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessing Auburn University Library's Tiger Information Literacy Tutorial (TILT)
Authors: Noe Nancy W. , Bishop Barbara A.
Published: June 2005

Purpose

During Spring semester 2001, Auburn University Libraries launched the Tiger Information Literacy Tutorial (TILT), based on the Texas Information Literacy Tutorial, designed by librarians at the University of Texas at Austin. This work assesses the effectiveness of the tutorial.

Design/methodology/approach

In‐depth analysis of data collected over three semesters is presented.

Findings

Following the Texas model, Auburn's TILT is comprised of three modules, covering searching, selecting, and evaluating information resources. Overall student perceptions of the tutorial, including technology difficulties, is reviewed; and students' personal views of their own research skills are discussed. The online information tutorial was viewed as effective, with the data indicating a need for additional study and improvement.

Value

As advances are made in computer‐aided and hypermedia‐aided instruction, the tutorial will continue to evolve as a learning tool.
Was this guide helpful? Users' perceptions of subject guides
Authors: Courtois Martin P. , Higgins Martha E. , Kapur Aditya
Published: June 2005

Purpose

Most academic libraries make subject or research guides available on their web sites. Little is known, however, in terms of user satisfaction with guides. This study examines methods used to evaluate guides and reports on an online survey placed on each of more than 80 web‐based guides provided by Gelman Library, George Washington University.

Design/methodology/approach

The survey, borrowing an approach used by Amazon.com and other web sites, consisted of a single question – Was this guide useful – and a comments box.

Findings

Two hundred ten responses were received during Fall semester 2003. Fifty two percent of responses rated guides as Very Helpful or Somewhat Helpful, while 40 percent gave ratings of Not Helpful or a Little Helpful.

Originality/value

Although limited in scope, this simple survey revealed positive elements of the guides and identified problems that could be addressed immediately. The survey also helped to identify larger issues that will benefit from additional user input.
Incoming international students and the library: a survey
Authors: Jackson Pamela A.
Published: June 2005

Purpose

To assess incoming international students' library and computer experience before coming to the US, and to determine their current library needs.

Design/methodology/approach

A study was undertaken to assess incoming international students' exposure to libraries, computer literacy skills, and to determine their library needs. Results from a survey conducted in August 2003 include demographic information about incoming students, computer and library use before coming to the US, library concepts that are new to them, and opinions about the library.

Findings

Survey results show that international students arrive in the US with high levels of computer literacy and that most incoming students have used a library in their home country. Findings suggest that international students would benefit from specialized library information competence and orientation programs.

Research limitations/implications

This study was conducted just over 3 weeks after the Dr Martin Luther King, Jr Library opened its doors. Thus, student survey responses were collected during an unsettled period. While students perceive themselves as understanding library terminology, no testing was conducted to confirm this. Further study is needed to determine the extent of their knowledge of library terms and jargon.

Practical implications

Survey results have led to the implementation of library programs that support the information competence, retention and academic success of international students.

Originality/value

Few studies include the international students themselves to determine their library and educational needs. This study offers a current view of the library needs of international students as they perceive them.
Elements of active learning in the online tutorials of ARL members
Authors: Hrycaj Paul L.
Published: June 2005

Purpose

The purpose of this paper is to determine the extent of the use of active learning in the online tutorials of members of the Association of Research Libraries (ARL) and to compare these results with those found in a similar study done in 1999 by Nancy Dewald, and also to determine what major types of active learning these sites offer.

Design/methodology/approach

The focus of the study in this paper was on “stand‐alone” library skills tutorials, as opposed to those tutorials that need to be used in conjunction with an in‐person course in order to be effective. After defining what counts as a “tutorial” and “active learning”, ARL sites were reviewed to determine whether they employ elements of active learning.

Findings

This study found that the percentage of ARL tutorials that employ active learning is significantly greater than the percentage of such tutorials in Dewald's study. Also, some categories of the methods of active learning employed in these tutorials are determined and examples for each category are provided.

Research limitations/implications

Because web page content is fluid and open to frequent changes, the findings of this study may not be accurate by the time of publication.

Originality/value

This paper updates and expands on (by focusing on ARL members) the findings of Dewald's original study of online tutorials. Also, the categories of active learning discussed and the examples of these provided can offer some aid to libraries that wish to add to or expand the use of active learning in their online tutorials.
Embedding a librarian in the classroom: an intensive information literacy model
Authors: Hearn Michael R.
Published: June 2005

Purpose

To describe an information literacy (IL) component for an undergraduate program, and to discuss the design and implementation of a faculty/librarian collaboration to teach first‐year English students how to do appropriate and thorough research.

Design/methodology/approach

The librarian was assigned to be a co‐instructor in the course, taught a significant percentage of the research material, and participated in the assigning of students' grades.

Findings

Each session taught by the librarian is described in detail, and the impact of the experiment on the students, the instructors and the college is addressed.

Originality/value

The paper addresses the benefits and difficulties of adding an intensive IL component on a small college campus.
Ten must reads for new academic librarians
Authors: Landry Abbie
Published: June 2005

Purpose

To inform new academic librarians and their mentors about books, articles, and web sites which provide guidance in becoming a professional librarian and achieving tenure and promotion.

Design/methodology/approach

New academic librarians are often ignorant of important publications that can help them succeed in becoming successful professional librarians. Many are not prepared for what is expected of them in an academic library. These ten works, arranged by ten categories, contain an explanation of the importance of the work and its value to the new professional librarian. These resources range from topics such as achieving tenure to learning about state publications.

Findings

These ten works were chosen based on their clarity, usefulness, and content. Full bibliographic information or pertinent URL is provided for each source.

Practical implications

This list has been successfully used by new librarians mentored by the author and will be of value to both new hires finding their way through tenure, promotion, and evaluations, as well as providing practical information for mentors to give their charges.

Originality/value

Other bibliographies provide information on how to do research, publications, pros and cons of tenure, etc., but this one brings together practical information that is instantly useful, as well as filling in gaps in a new librarian's knowledge on becoming a successful librarian.
Fruits of the tree: resources on Shaker art
Authors: Harrington Sara
Published: June 2005

Purpose

Provides students, scholars, and interested parties an introductory essay and selected bibliography of recent resources on the art and material culture of the Shakers, a communitarian religious group who lived in the United States from the 18th to 21st centuries.

Design/methodology/approach

Introduces and annotates periodical articles, monographs, and exhibition catalogues examining Shaker art and material culture dating from 1987 to the present.

Findings

Provides information about each source, discusses the characteristics of current scholarship on Shaker art, and describes sources that contain unique scholarly contributions and quality reproductions of well and lesser known Shaker objects.

Practical implications

Provides a point of departure for an exploration of Shaker studies, focusing on the art and material culture of the Shakers, and highlights important sources within the growing body of literature on the Shakers.

Originality/value

As the only recent annotated bibliography of material on Shaker art, the article provides access to interdisciplinary resources that are widely scattered within the humanities literature and thus previously difficult to locate. The article also serves to bring resources on Shaker art and material culture to a wider audience, since the special libraries devoted to Shaker collection do not have electronic catalogs, and are largely limited to on‐site access.
The impact of overqualification on job search
Authors: Wald Steven
Published: June 2005

Purpose

The two main purposes of the paper are: first, to provide an empirical test of the widely‐held view among employers that overqualified workers are less committed as evidenced by heightened levels of job search, and second, to evaluate the three explanations of overqualification (matching theory, the theory of differential overqualification, and the career mobility hypothesis) in which job search plays a central role.

Design/methodology/approach

Maximum likelihood probit estimation is conducted on a sample of employed Canadians aged 18 and over who were surveyed in 2000. Predictors of job search are derived from the economic assumption that the employee's decision to undertake job search depends on a cost‐benefit assessment.

Findings

The empirical results indicate that overqualified workers are more active job searchers, and lend support to the matching theory view that overqualification is sub‐optimal from the worker's perspective.

Originality/value

This paper adds to the small number of European studies exploring the connection between overqualification and job search. The impacts of overqualification are especially important for Canadian employers given the high incidence of overqualification of the Canadian work force.
The relationship between organizational culture and withdrawal intentions and behavior
Authors: Carmeli Abraham
Published: June 2005

Purpose

The goal of the present study is to examine the influence of five dimensions of organizational culture (i.e. job challenge, communication, trust, innovation and social cohesiveness) on employees’ withdrawal intentions and behavior. Specifically, three forms of employees’ withdrawal intentions (i.e. from the occupation, job, and organization), and one form of employees’ withdrawal behavior (i.e. self‐reported absenteeism) are examined.

Design/methodology/approach

The paper investigates these relationships among social workers in the Israeli health care system through a structured questionnaire. Regression analyses were employed to test the research hypotheses.

Findings

The findings of this study indicate that an organizational culture that provides challenging jobs, diminishes employees’ absenteeism, and withdrawal intentions from the occupation, job, and the organization. The results also show that other dimensions of organizational culture were not significantly correlated with the dependent variables, with the exception of the relationship between a culture of innovation and employees’ withdrawal intentions from the job.

Originality/value

This study contributes to a better understanding of the influence of organizational contexts (e.g. culture) on the development of multiple withdrawal intentions and behaviors among social service employees in the health care sector.
Efficiency and productivity of employment offices: evidence from Sweden
Authors: Althin Rikard , Behrenz Lars
Published: June 2005

Purpose

This paper aims to measure the efficiency and productivity of Swedish employment offices.

Design/methodology/approach

Using four inputs, five outputs, and two quality attributes the efficiency and productivity of 253 Swedish employment offices are evaluated using models of relative technical efficiency and Malmquist productivity indices. The results are computed as solutions to linear programming problems for the 1992‐1995 periods.

Findings

Results of the study find that the mean efficiency across offices varies between 74 and 78 percent. The mean productivity change demonstrates a decrease of 11 percent during the 1992‐1993 period, and an increase of 7 and 13 percents during 1993‐1994 and 1994‐1995 respectively.

Research limitations/implications

Different background characteristics of job seekers could possibly bias the result for some of the offices. Further research could use a dynamic model where different job seeker characteristics are taken into consideration.

Practical implications

The paper provides an opportunity for inefficient/low productivity offices to study how offices identified as more efficient are producing their services.

Originality/value

This paper demonstrates how efficiency and productivity could be measured in a multi‐input, multi‐output employment office service sector setting where quality aspects are allowed to play a part.
The influence of managerial power and credibility on knowledge acquisition attributes
Authors: Politis John D.
Published: June 2005

Purpose

This paper examines the relationship between credibility, the dimensions of power and a number of knowledge acquisition attributes.

Design/methodology/approach

The study involves a questionnaire‐based survey of employees from a number of organisations operating in the United Arab Emirates (UAE). A total of 130 useable questionnaires were received from employees who are engaged in self‐managing activities from seven companies. These were subjected to a series of correlational and regression analyses.

Findings

There are three major findings in this research. First, the relationship between expert power and the knowledge acquisition attributes of personal traits, control and negotiation is positive and significant. Second, the constructs of coercive and referent power are likely to have a negative influence on employees' knowledge acquisition and knowledge sharing. Finally, the findings have clearly shown that the management dimension of credibility has a positive and significant impact on the knowledge acquisition attributes of control and negotiation.

Practical implications

The study shows that the real challenge for organisations in the UAE is to provide a working environment that encourages and fosters expert power and credibility and, by extension knowledge acquisition and knowledge sharing.

Originality/value

There is a paucity of research in this area and this paper makes a contribution towards filling this gap.
Jaguar “Roadmap” rethinks self‐piercing technology
Authors: Mortimer John
Published: June 2005

Purpose

Describes how Jaguar Cars is evaluating a technology roadmap to assess future manufacturing processes.

Design/methodology/approach

Describes the major production line technologies that are under close scrutiny for the next ten years for use in the Jaguar Cars' production plants at Castle Bromwich and at Halewood, Merseyside, both in the UK. Technologies under review include ultrasonic welding, friction stir spot welding, laser welding and self‐piercing rivets.

Findings

The use of self‐piercing rivets is already used in production at Jaguar for the aluminium‐bodied XJ saloon. But developments of the process are already underway in readiness for the next new model. However, at the same time, engineers are examining other techniques including ultrasonic joining and friction stir spot welding, both of which at the subject of research work in the US and the UK. Use of pedestal guns and blow feeding devices is expected to bring improvements in cost.

Research limitations/implications

Engineers at Jaguar are carrying out research and development, both in‐house and with various research bodies and universities to establish the most beneficial processes for the joining of aluminium sheet, extrusion and cast components that go to form an aluminium car body. For successful joining aluminium requires low heat input solutions. At present, self‐piercing rivets offer the best solution, but Jaguar engineers are looking at other processes including ultrasonic joining and friction stir spot welding. The aim is to find processes that are fast and cost‐effective. In the meantime, Jaguar will continue to use self‐piercing rivets for aluminium structures.

Practical implications

The practical implications of the work will lead to reduced cycle times which in turn will help to make the manufacture of aluminium car bodies more cost‐effective.

Originality/value

BMW claims it is the first car maker to make use of bowl‐feeding self‐piercing rivets for the manufacture of aluminium body‐in‐white.
Interfacing industrial robotic systems with manufacturing tracking and control software: a choice for semi‐autonomous manufacturing systems
Authors: Norberto Pires J.
Published: June 2005

Purpose

This technical paper reports the development of an industrial robotic labeling system, designed to insert identification labels on rolls of paper coming from an industrial paper machine.

Design/methodology/approach

The system was developed for an existing installation comprising a paper machine, a roll measuring and weighting station and a roll wrapping machine. The labels identify each roll by means of barcodes, which are used internally in the factory to identify and store each roll at the automatic warehouse and by the customer company for similar purposes.

Findings

In describing an industrial application designed for labeling applications, this paper discusses and details a software interface designed to command shop‐floor manufacturing systems remotely from the manufacturing tracking software. This adds in terms of flexibility and agility, since all available operations were implemented in a very general way requiring only simple parameterization to specify the individual operations.

Practical implications

Since the TCP/IP server is a general implementation, using the BSD compatible TCP/IP socket implementation from Microsoft, it can receive commands from virtually any client. This makes this robotic cell interface an interesting way to command shop‐floor manufacturing systems.

Originality/value

Demonstrates a method for controlling shop‐floor manufacturing systems that has broad applications.
The steady uptake of robots for dishwasher manufacture
Authors: Kochan Anna
Published: June 2005

Purpose

Aims to determine how robotics is used in white goods manufacture.

Design/methodology/approach

Interviews production specialists at BSH Bosch and Siemens Hausgerate about the application of robots to dishwasher manufacture at the company's Dillingen plant in Germany, and reviews several robot applications at the facility.

Findings

Robots have an important though limited role to play in dishwasher manufacture due to most automation needs being met by dedicated machinery

Originality/value

Reveals how the white goods industry views robotics and its value to production
Landmine detection using an autonomous terrain‐scanning robot
Authors: Najjaran Homayoun , Goldenberg Andrew A.
Published: June 2005

Purpose

Describes a dual‐arm mobile manipulator that can autonomously scan natural terrain using a typical handheld landmine detector in a manner similar to a human operator.

Design/methodology/approach

Presents a terrain‐scanning robot that consists of two articulated arms mounted on an off‐road remotely operated vehicle. One arm carries a laser and four ultrasonic rangefinders to build a terrain map. The map is used in real time to generate an obstacle‐free path for the second arm that manipulates the landmine detector autonomously. The arms are mounted on the vehicle that is controlled by an operator from a safe distance. Motion planning and control of the robot is carried out using an embedded computer that is linked to a host computer to transmit the detector data and operator commands.

Findings

Finds that the terrain‐scanning robot can effectively manipulate a relatively large landmine detector on rugged terrain with undulations and obstacles.

Research limitations/implications

Proposes real‐time motion planning that may be equally applicable to other mobile manipulators.

Practical implications

Provides a technology that together with state‐of‐the‐art landmine sensors will offer a safe solution for detecting hidden landmines and clearing them from the postwar countries.

Originality/value

Introduces the concept of a dual‐arm mobile terrain scanning robot for landmine detection in off‐road missions and civilian areas where truck‐mounted detectors are inefficient.
Evolving locomotion gaits for quadruped walking robots
Authors: Golubovic Dragos , Hu Huosheng
Published: June 2005

Purpose

This paper presents an evolutionary algorithm (EA) for Sony legged robots to learn good walking behaviours with little or no interaction with the designers. Once the learning method is put into place, the module can learn through its interaction with the real world.

Design/methodology/approach

An EA for developing locomotion gaits of quadruped walking robots is presented in this paper. It is based on a hybrid approach that changes the probability of genetic operators in respect to the performance of the operator's offspring.

Findings

The mutating and combination behaviours of the genetic algorithms allow the process to develop a useful behaviour over time. The resulting gait from this training proved to be a better solution than the non‐interference training for movements over all types of surfaces, pointing to a local optima being discovered in the non‐environmental interference situation.

Research limitations/implications

The behaviour of these algorithms is stochastic so that they may potentially present different solutions in different runs of the same algorithm. The mechanism described here has several features that should be noted. It allows rapid parameterisation of operator probabilities across the range of potential genetic algorithms and operator set. It is tailored to a steady state reproduction scheme. It would not be literally applicable to problems with noisy evaluation functions.

Originality/value

Provides novel application of genetic algorithms to a potentially practical application area.
Demographic characteristics of consumers who find it difficult to decide
Authors: Walsh Gianfranco , Mitchell Vincent‐Wayne
Published: June 2005

Purpose

The puropse of this article is to identify consumers who experience difficulty in making their buying decisions, especially in the face of variety of choice, proliferation of brand choice, small inter‐brand differences, brand counterfeiting, marketing communication overload and so on.

Design/methodology/approach

A questionnaire administered to 264 consumers in north Germany used a scale developed by the authors at the University of Hanover in 2002 to measure three types of difficulty in marketplace decision making. Those relate to similarity among product‐service offerings available, information overload, and marketing communications that lack clarity. Data collected were analysed by ANOVA and hierarchical cluster analysis.

Findings

ANOVA suggested that high levels of marketplace decision difficulty were characteristic of older, less well‐educated female consumers. Subsequent cluster analysis identified four distinct and meaningful consumer types, in terms of “marketplace decision difficulty” or MPDD.

Research limitations/implications

The present study was restricted to a single large city in one European country, and one of the test statistics was perhaps too rigorous for useful conclusions in the case of some variables, but the findings do contain clear managerial implications and future research developments are proposed.

Practical implications

Marketing strategists should find it useful to understand the demographics of consumers who are likely to experience difficulty in making marketplace decisions – for instance, to segment audiences for their marketing communications, and to vary style and content accordingly.

Originality/value

This study offers a practical market segmentation scheme, based on demographic influences on decision‐making behaviour.
Relationship marketing: schools of thought and future research directions
Authors: Palmer Roger , Lindgreen Adam , Vanhamme Joëlle
Published: June 2005

Purpose

The purpose of this article is to challenge the applicability of the traditional micro‐economic framework for analysing marketing situations and actions in the contemporary marketing environment. To assess the validity and value of relationship marketing as an alternative paradigm. To identify fruitful directions for further research.

Design/methodology/approach

The literature of relationships and relationship marketing was systematically reviewed and thoroughly analysed, and a conceptual framework built from the findings.

Findings

Three key schools of thought are identified, examined and discussed, and their main components explained and examined. Various perspectives on exchange relationships are discussed. Two specific tools for implementation of relationship marketing are evaluated. With a clear conceptual frame of reference thus established, the second part proposes a number of fruitful directions for further research. These include a bibliometric study to assess whether or not a consistent theory of relationship marketing exists, and a rigorous identification of contextual factors determining different marketing styles.

Research limitations/implications

The second part of the paper explicitly discusses research directions to take the new paradigm forward, in theory and in practice.

Practical implications

The combination of a more rigorous conceptual framework and a clear research agenda holds the promise of significant progress in the practical implementation of a young sub‐discipline.

Originality/value

The paper presents a distinctively wide‐ranging and thorough overview of the subject of value to both academic researchers and marketing practitioners.
Symmetrization of asymmetrical three‐phase load supplied from non‐ideal periodic non‐sinusoidal voltage source using simplified structure of the compensator
Authors: Dębowski Krzysztof , Pasko Marian
Published: June 2005

Purpose

The problems presented in the paper concern a three‐phase four‐wire system with periodical non‐sinusoidal voltage sources with inner impedances and asymmetrical linear three‐phase loads. Generally, the line currents of the system are asymmetrical. The purpose of the paper is to improve the working conditions of the system by means of symmetrization.

Design/methodology/approach

A method of symmetrization of these systems has been proposed. In this paper, the symmetrization problem has been solved by using the symmetrical components theory and compensation of reactive power for each of voltage harmonics under consideration.

Findings

After symmetrization currents become symmetrical and their RMS values and active power on source impedances become lower. The realization of symmetrization makes possible: reduction of RMS values of source currents, an assurance of equal loads for individual phases of the system supplied from sources with inner impedances, after symmetrization the voltage source generates and load consumes greater useful active power.

Originality/value

The simplified structure of the compensator has been proposed in the paper. The symmetrization has been presented with reference to new structure of the compensator.
Non‐negative matrix factorization and its application in blind sparse source separation with less sensors than sources
Authors: Li Yuanqing , Cichocki Andrzej
Published: June 2005

Purpose

Proposes a non‐negative matrix factorization method.

Design/methodology approach

Presents an algorithm for finding a suboptimal basis matrix. This is controlled by data cluster centers which can guarantee that the coefficient is very sparse. This leads to the proposition of an application of non‐matrix factorization for blind sparse source separation with less sensors than sources.

Findings

Two simulation examples reveal the validity and performance of the algorithm in this paper.

Originality/value

Using the approach in this paper, the sparse sources can be recovered even if the sources are overlapped to some degree.
Transient analysis of nonlinear dynamic circuits using a numerical‐integration method
Authors: Tadeusiewicz Michał , Hałgas Stanisław
Published: June 2005

Purpose

Developing an efficient second‐order integration method of transient analysis of nonlinear dynamic circuits which overcomes the main drawback of the trapezoidal rule.

Design/methodology/approach

Dynamic circuits including transistors and operational amplifiers are considered. A new family of two‐step, second‐order numerical integration algorithms has been developed using a polynomial approximation.

Findings

The algorithms have been worked out which are implicit, A‐stable and they depend on a parameter which is allowed to be changed during the computation process according to a proposed strategy. Also the variable step‐size formula has been derived enabling us to eliminate a restarting procedure. The method has been implemented and tested using several representative circuits. It has been compared, both theoretically and via numerical examples, with the alternative well known algorithms: the trapezoidal rule and the backward differentiation formula of order two.

Research limitation/implications

The algorithms developed in the paper are two‐step and second‐order, consequently the step size cannot be too large and the algorithms are not L‐stable.

Originality/value

A new family of two‐step implicit integration algorithms is developed. It can be useful for the analysis and design of electronic circuits.
Curl‐conform source fields in finite element formulations
Authors: Dular Patrick
Published: June 2005

Purpose

This paper proposes an automatic procedure to characterize discrete source fields.

Design/methodology/approach

A technique is developed to characterize curl‐conform fields to be used as source fields or non‐local basis functions in finite element formulations. A reduced characterization of such fields using curl‐conform finite elements is defined. An automatic construction of these curl‐conform spaces is proposed.

Findings

A reduced characterization of such fields is shown to be convenient for the coupling with complementary reaction fields and for simply and explicitly defining non‐local quantities, such as currents in h‐conform magnetodynamic formulations. The reduced form rests on the choice of supports for the fields limited to reduced cut spaces associated with cuts making the definition domain simply connected.

Originality/value

Develops a procedure to simplify the construction of curl‐conform source fields.
Analysis of iron loss under distorted elliptical rotating flux of SPM motor
Authors: Takahashi N. , Fukum A. , Miyagi D.
Published: June 2005

Purpose

In this paper, a new method for estimating iron loss under a distorted elliptical rotating flux is proposed.

Design/methodology/approach

In order to precisely analyze the iron loss of rotating machines, the iron loss under distorted rotating flux should be taken into account. However, reports of precise analysis considering measured iron loss data under rotating flux are few.

Findings

The iron loss of surface permanent magnet (SPM) motor model proposed by the investigation committee of IEE of Japan is estimated using the proposed method. The experimental examination is carried out by measuring the iron loss of the motor using a torque meter.

Originality/value

Examines an estimation method of iron loss of motors.
Robust and efficient FETI domain decomposition algorithms for edge element approximations
Authors: Toselli Andrea , Vasseur Xavier
Published: June 2005

Purpose

A family of preconditioned dual‐primal FETI iterative algorithms for the solution of algebraic systems arising from edge element approximations in two dimensions is presented.

Design/methodology/approach

The primal constraints, which determine the size of the coarse problem to be solved at each iteration step, are here suitable averages over subdomain edges. The condition number of the corresponding methods is independent of the number of subdomains and possibly large jumps of the coefficients.

Findings

For h finite elements, it grows only polylogarithmically with the number of unknowns associated with individual substructures, while for hp approximations on geometrically refined meshes, it is independent of arbitrarily large aspect ratios.

Originality/value

Proposes an algorithm with a rate of convergence that is independent of possibly large jumps of the coefficients and mesh aspect ratios.
Comparison of semi‐analytical and FEM solutions in a certain magnetic fluid dynamics problem
Authors: Ziolkowski Marek , Brauer Hartmut , Kuilekov Milko
Published: June 2005

Purpose

To provide a new semi‐analytical procedure which is much faster than FEM and for this reason can be applied in a reconstruction of an interface between two conducting fluids (magnetic fluid dynamics problem) by means of magnetic field tomography.

Design/methodology/approach

Three approaches are compared: a simple analytical solution (AS1), a modified semi‐analytical solution (AS2), and the finite element method solution. The modified semi‐analytical approach takes into account an information about azimuthal spatial harmonics received from the Fourier analysis of magnetic flux density distributions calculated by FEM. AS1 and AS2 have been compared for different modes of the interface using FEM solution as a reference.

Findings

It is shown that for small perturbations the AS2 in every case provides smaller errors than AS1 although for some modes (14,24) the quality of the solution is still not satisfactory.

Originality/value

This paper describes a new technique for the analysis of electromagnetic field which can be also applied in other problems.
Qualification of the inverse problem of defect reconstruction using optimized mesh database
Authors: Gyimóthy Szabolcs , Pávó József
Published: June 2005

Purpose

To propose a novel method for defect reconstruction in electromagnetic non‐destructive testing (NDT).

Design/methodology/approach

The inversion method is based on an optimized database that contains the measured signals for some predefined defect prototypes. The database is supported by an anisotropic simplex mesh, which has been generated adaptively in the abstract n‐dimensional space, spanned by the model parameters of the defect type. The actual reconstruction reduces to a mesh search and interpolation. The described theory is demonstrated in the paper by a solved NDT test problem.

Findings

We have realized that in addition to sole defect reconstruction, the database provides meta‐information about the quality of the inversion, the suitability of the chosen defect model parameters, as well as the capabilities of the testing experiment.

Research limitations/implications

Defect models having several parameters require a sophisticated mesh generation algorithm, which works in higher dimensions.

Originality/value

In the authors' opinion the mesh database approach offers a totally new point of view of a given inverse problem, and may help in the better understanding of its nature.
An integral approach based on dual discretization and method of moment for the solution of static electric field
Authors: Canova A. , Gruosso G. , Repetto M.
Published: June 2005

Purpose

The scope of the work is to provide an hybrid numerical technique for the solution of electric field.

Design/methodology/approach

In this paper an integral approach for the solution of static electric field based on a dual discretization (DD) and on a surface method of moment (MoM) is presented. The proposed technique is applied to the solution of 3D electric field problems where different perfectly conducting bodies are placed in a homogeneous and isotropic medium. The approach is also extended to the analysis of static current field. In the presented formulation MoM is applied on a surface domain which is discretized according to a baricentrical dual scheme.

Findings

The procedure has been applied to several practical cases and it represents an efficient tool for the evaluation of lumped circuit parameters as capacitances of 3D conducting bodies and ground resistance of grounding systems.

Research limitations/implications

The formulation presented in the paper is limited to the calculus of electric field in homogeneous media. For future development the authors are working in order to include non‐homogeneous media.

Practical implications

The proposed approach aids the designer of electrical systems as large scale grounding systems or integrated circuit connections in the calculations of lumped electrical parameters.

Originality/value

The originality of the paper lies in the coupling of MoM with finite formulation and DD.
Parallelized computation of compressed BEM matrices on multiprocessor computer clusters
Authors: Buchau André , Hafla Wolfgang , Groh Friedemann , Rucker Wolfgang M.
Published: June 2005

Purpose

Various parallelization strategies are investigated to mainly reduce the computational costs in the context of boundary element methods and a compressed system matrix.

Design/methodology/approach

Electrostatic field problems are solved numerically by an indirect boundary element method. The fully dense system matrix is compressed by an application of the fast multipole method. Various parallelization techniques such as vectorization, multiple threads, and multiple processes are applied to reduce the computational costs.

Findings

It is shown that in total a good speedup is achieved by a parallelization approach which is relatively easy to implement. Furthermore, a detailed discussion on the influence of problem oriented meshes to the different parts of the method is presented. On the one hand the application of problem oriented meshes leads to relatively small linear systems of equations along with a high accuracy of the solution, but on the other hand the efficiency of parallelization itself is diminished.

Research limitations/implications

The presented parallelization approach has been tested on a small PC cluster only. Additionally, the main focus has been laid on a reduction of computing time.

Practical implications

Typical properties of general static field problems are comprised in the investigated numerical example. Hence, the results and conclusions are rather general.

Originality/value

Implementation details of a parallelization of existing fast and efficient boundary element method solvers are discussed. The presented approach is relatively easy to implement and takes special properties of fast methods in combination with parallelization into account.
Electric machine operational modeling utilizing coupled electromagnetic and electric drives simulations
Authors: Mohammed O.A. , Liu Z. , Liu S. , Abed N.Y.
Published: June 2005

Purpose

The purpose of this research is to develop new techniques for component physical modeling for the dynamic simulation of integrated power systems.

Design/methodology/approach

A FE‐based phase variable model is proposed so as to achieve fast and accurate simulation. Such a model is established based on the nonlinear transient FE analysis, in order to take into consideration the harmonic effects due to the nonlinear magnetization property, magnetic circuit geometry as well as other design variations.

Findings

In the FE‐based phase variable model, the inductances are described as functions of the phase angle and the magnitude of winding currents, the rotor position and other operational parameters. They are obtained from the transient FE solutions, stored in tables, and retrieved during the simulation. The FE‐based phase variable model is implemented in Simulink in two ways. The first is the equation‐based block and the second is the circuit component‐based block. The FE‐based phase variable models of various electrical components in the power system were studied. This includes various types of rotating machines and transformers. Examination and application examples show the correctness and effectiveness of the proposed operational modeling procedures.

Originality/value

The developed FE‐based physical phase variable model is as accurate as the full FE model with much faster simulation speed. It will benefit the dynamic simulation of integrated power system. This combination of physical modeling and integrated dynamic simulation is original and represents an added value to the state‐of‐the‐art in this field.
Band gaps in photonic crystals with dispersion
Authors: Szabó Zsolt , Kádár György , Volk János
Published: June 2005

Purpose

The paper presents the band gap computation in one‐ and two‐dimensional photonic crystals built up from porous silicon. The frequency dispersion of the dielectric materials is taken into account.

Design/methodology/approach

The behavior of the light in a photonic crystal can be well described by the Maxwell equations. The finite difference time domain (FDTD) method is applied to determine the band structure. The frequency dependence of the dielectric constant is taken into account by a sum of second‐order Lorenz poles. The material parameters are determined applying a conjugate gradient‐based minimization procedure. Passing a light pulse of Gaussian distribution through the photonic crystal and analyzing the transmitted wave can explore the photonic bands.

Findings

The realized simulations and visualizations can lead to a much better understanding of the behavior of electromagnetic waves in dispersive photonic crystals, and can make possible to set up experimental conditions properly. The obtained results show again that silicon and porous silicon can be used for the fabrication of photonic crystals.

Research limitations/implications

Due to the high computational requirements of the three‐dimensional case we plan to work out a parallel version of the presented FDTD algorithm.

Originality/value

This paper presents a simple way to take into account the frequency dispersion in the simulation of photonic crystals with the FDTD method.
Identification and simulation of a circuit‐based model of magnetic hysteresis
Authors: Gruosso G. , Repetto M.
Published: June 2005

Purpose

The scope of the work is to provide an identification procedure for an hysteresis model based on nonlinear circuit cells.

Design/methodology/approach

An identification procedure for an hysteresis model based on nonlinear circuit cells is presented. The response of elementary cell is equal to a generalized play operator. The procedure allows the identification of the limit symmetric hysteresis loop and of minor loops. The identification procedure is based on the relationship between the circuit parameters and the discretization of the first derivative of the BH curve by means of a staircase function.

Findings

The model obtained is employed for the simulation of soft magnetic composite material cores under different supply voltage waveforms. The proposed identification procedure is able to define an accurate model of an hysteretic material with a low number of elemental network cells. The identification algorithm is simple and makes use of the limit hysteresis cycle only. Symmetric minor loops are used to tune “soft” operators for the correct reconstruction of cycles which do not reach saturation.

Research limitations/implications

The model is limited to scalar and static hysteresis model.

Practical implications

The model obtained can be used in network simulator like SPICE in order to model circuits in which magnetic devices are involved.

Originality/value

The circuit hysteresis model has been presented in literature, while its identification is newly proposed by the authors.
An analysis of magnetic shielding against DC power lines based on homogenization
Authors: Waki H. , Igarashi H. , Honma T.
Published: June 2005

Purpose

To analyze effectively magnetic shielding effects by shields with fine structure.

Design/methodology/approach

Simplification of the fine structure makes it possible to analyze them efficiently. The authors have introduced a homogenization method to estimate effective permeability of magnetic composite structure for the static field. The homogenization method is applied to the analysis of magnetic shields composed of steel plates and steel rods against DC power lines to test its feasibility.

Findings

The properties of the magnetic shielding are analyzed by using the homogenization method. The errors of the magnetic fields increase in case of very few layers.

Originality/value

The simplification of the magnetic shields with fine structure by using the homogenization method makes it possible to analyze efficiently magnetic shielding effects, although the accuracy becomes worse in case of very few layers.
A FEM‐BEM approach using level‐sets in electrical capacitance tomography
Authors: Kortschak Bernhard , Brandstätter Bernhard
Published: June 2005

Purpose

For the spatial reconstruction of a two phase flow, as it might occur in a pipe, the main problem has always been the blurring of the resulting images.

Design/methodology/approach

In this paper, we present a method where blurring is implicitly avoided by the use of level sets. The level set method describes the iteratively evolving interface between different materials. The underlying field problem is solved with the boundary element method formulated in the region, where the degrees of freedom are present and the finite element method in all other regions.

Findings

Finally reconstruction results of an electrical capacitance tomography sensor are presented to show the validity of the method.

Originality/value

Presents a method where blurring is avoided by the use of level sets.
Statistical robust design using the unscented transformation
Authors: Steiner Gerald , Watzenig Daniel , Magele Christian , Baumgartner Ulrike
Published: June 2005

Purpose

To establish a statistical formulation of robust design optimization and to develop a fast optimization algorithm for the solution of the statistical design problem.

Design/methodology/approach

Existing formulations and methods for statistical robust design are reviewed and compared. A consistent problem formulation in terms of statistical parameters of the involved variables is introduced. A novel algorithm for statistical optimization is developed. It is based on the unscented transformation, a fast method for the propagation of random variables through nonlinear functions. The prediction performance of the unscented transformation is demonstrated and compared with other methods by means of an analytical test function. The validity of the proposed approach is shown through the design of the superconducting magnetic energy storage device of the TEAM workshop problem 22.

Findings

Provides a consistent formulation of statistical robust design optimization and an efficient and accurate method for the solution of practical problems.

Originality/value

The proposed approach can be applied to all kinds of design problems and allows to account for the inevitable effects of tolerances and parameter variations occuring in practical realizations of designed devices.