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Describes the design and operating principles of fluxgate sensors and magnetometers. Polarity determination and compensation for temperature and high frequency (> 100Hz) alternating magnetic fields are also discussed.

The purpose of this paper is to propose a new model that is inclusive and practical because of the deficiencies in models for construct measurement. Further, the authors demonstrate the value of the proposed model by describing its application to the development and validation of a multi-dimensional construct, enviropreneurial orientation. Although used in the literature, enviropreneurial orientation had not been developed nor tested as a construct. The paper provides detailed explanation of development and validation processes exemplified by experiences of research into the factors that motivate individual enviropreneurial orientation among owner/managers in supply chains.

The authors review models of construct development and propose an eight step model to overcome the deficiencies in the existing models. The eight steps are: defining the construct; identifying its dimensions; generating measurement items for each dimension; pretesting the measurement items; collecting data; constructing scales; analysing reliability; and evaluating the relationships. Each step is explained through examples based on the authors’ experience in using the model to develop the new construct – enviropreneurial orientation.

All correlation results were positive and significant as were the multiple regression results with one exception, competitive aggressiveness.

The authors provide a practical model to guide new construct measurement development which can be used by researchers and research students for multi-dimensional constructs, especially they are constrained by time and financial resources. By using an example to demonstrate the applicability of the model, the authors go beyond the usual description of construct development models to make the proposed model more comprehensible and thus useful.

Gives a bibliographical review of the error estimates and adaptive finite element methods from the theoretical as well as the application point of view. The bibliography at the end contains 2,177 references to papers, conference proceedings and theses/dissertations dealing with the subjects that were published in 1990‐2000.

Gives a bibliographical review of the finite element meshing and remeshing from the theoretical as well as practical points of view. Topics such as adaptive techniques for meshing and remeshing, parallel processing in the finite element modelling, etc. are also included. The bibliography at the end of this paper contains 1,727 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1990 and 2001.

The purpose of this paper is to examine the effect of varying compaction pressure on magnetic properties of self-developed soft magnetic composite (SMC) cores. The change in shape of ferromagnetic hysteresis curves has – in turn – the impact on the values of hysteresis model parameters. The phenomenological GRUCAD model is chosen for description of hysteresis curves.

Several cylinder-shaped cores have been made from a mixture of iron powder and suspense polyvinyl chloride using a hydraulic press with a form and a band with a thermocouple for controlling heat treatment conditions. The only varying parameter in the study is the compaction pressure. The magnetic properties of developed cores have been measured using a computer-acquisition card and LabView software. The obtained hysteresis curves are fitted to the equations of the phenomenological GRUCAD model. This description is compliant with the laws of irreversible thermodynamics. The variations of model parameters are presented as functions of compacting pressure.

The compaction pressure has a significant impact on magnetic properties of self-developed SMC cores. The paper provides a number of charts useful for checking how the parameters of the hysteresis model are affected.

The present paper is limited to modelling symmetrical loops only. Description of more complex magnetization cycles is postponed to another, forthcoming paper.

The GRUCAD hysteresis model may be a useful tool for the designers of magnetic circuits. Its parameters depend on the processing conditions (in this study – the compaction pressure) of the SMC cores.

Modelling of magnetic properties of SMC cores has been carried so far using some well-known description like Preisach, Takács and Jiles–Atherton proposals. The GRUCAD model has a number of advantages, and it may be a useful alternative to the latter formalism. So far it has been used for description of hysteresis curves in conventional materials like non-oriented and grain-oriented electrical steels. In the present work, it is applied to novel SMC materials.