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This work discusses the use of exponentially and reciprocally decaying infinite elements and assesses their respective value for magnetostatic and eddy current problems. In particular, the need for different decaying parameters for different materials is shown to be detrimental to their application in many practical situations. A simple method, whereby a 2‐D solution is used to find the approximate boundary conditions for a closely truncated 3‐D mesh is presented and shown to give good results without the complications of infinite elements. This method is applied to a large eddy current problem.

A knowledge‐based system for forming quadrilateral finite elements, XFORMQ, was developed at the Centre of Flexible Manufacturing Research and Development of McMaster University, Canada. It automatically forms quadrilateral elements of good quality in conjunction with existing triangular mesh generators. XFORMQ can model geometries as complicated as those handled by triangular mesh generators. It allows for pre‐specified element sizes and rapid transition of element density. The concepts of ‘layer’ and ‘polygon patterns’, which considerably simplify the mesh generation rules and ensure the quality of formed elements, are introduced. Several test cases with different degrees of difficulties were used to evaluate XFORMQ's capabilities with satisfactory results. XFORMQ has the potential of generating meshes arising from the adaptive finite element analysis with quadrilateral elements.

This paper aims to investigate the internet web page metadata usage behavior in terms of their metadata element co‐occurrences. Metadata are designed to facilitate both web publishers/authors to organize their web pages and search engines to index the web pages accurately.

This study examines the types of metadata elements employed by different professional groups of web authors, the number of elements they prefer to use, and the types of element combinations they typically embed in their pages' HTML code.

The findings reveal that the “keyword” and “description” elements were the most popular single elements. The most popular combination of two elements was that of “keyword and description”. Very few authors included combinations of five elements. This study also shows that preferences for element combinations varied by domains.

This approach will enhance the current understanding of metadata usage behavior and may help search engine designers as they continue their quest for improved indexing and retrieval of web pages.

As forestry contributes to the reduction of greenhouse gases by CO₂ fixation, in recent years, use of wood in buildings has attracted all over the world more attention. However, construction of large wood structures is almost inexistent within urban areas in Japan. This is due to the Japanese law on fire protection of wood buildings in cities, which is considered very strict with severe requirements. This paper aims to present a research work relative to the development of one-hour fire-resistant wood structural elements for buildings in cities. The developed elements are composed of three layers made of laminated timber.

These wood structural elements, made of glued laminated timber with self-charring-stop, have sufficient fire resistance during and after a fire and comply with the strict Japanese standard for wood structural elements, which stipulates that such elements have to withstand the whole dead-load of concerned buildings after fire. To comply with such requirements, new elements of glued laminated timber with self-charring-stop layer were developed, and their performance was confirmed. Several fire-resistant tests conducted on columns, beams, column-beam joints, connections between beams and walls and beams with holes were carried out.

All tests proved that the elements have sufficient fire resistance. No damage was found out at the load-bearing part of the elements after testing. As the developed elements have two layers protecting the load-bearing part, the temperature in the load-bearing part could be retained below 260°C (carbonization temperature) and provide the elements with a sufficient fire resistance for 1 h.

These wood structural elements have already been applied in six projects, where large-size wooden buildings were constructed in urban areas in Japan.

The proposed structural elements use a novel technique. Every wooden element is composed of three layers made of glued laminated timber. The elements have a typical performance of self-charring-stop after fire without need for water of firefighters. More technologies related to these elements, including column-beam joints and beams with holes and effect of crack, were also developed to design and construct safe wooden buildings.

The purpose of this paper is to clarify the usefulness of characteristics analysis of an interior permanent magnet (IPM) motor using the 3‐D finite element method (FEM) with prismatic elements from the view point of the accuracy and the calculation time.

The authors analyzed characteristics of an IPM motor applied by the pulse width modulation (PWM) voltage source using the 3‐D FEM with prismatic elements and with tetrahedral elements; then compared the calculated results and the calculation time using prismatic elements with those using tetrahedral elements.

It was found that the calculated current and torque, and eddy current loss using prismatic elements are almost the same as those using tetrahedral elements. The calculation time using prismatic elements is shorter than that using tetrahedral elements.

This paper verifies the usefulness of the 3‐D FEM with prismatic elements through characteristics analysis of an IPM motor driven by the PWM voltage source.

In this paper, we introduce the concept of a supporting set for a general system. We study basic properties of supporting sets for a general system, supporting sets for subsytems of a system, homomorphic images of supporting sets for a system, and supporting sets for free sums and direct sums of systems.

The paper presents a new technique for a compatible transition from a h‐refined to a p‐refined finite element mesh. At one or more faces of particularly designed pNh‐transition elements a low order h‐discretization may be combined with a usual p‐mesh in the other parts of the elements. The pNh‐elements are conform finite elements which can be applied in an adaptive scheme controlled by a residue based error estimate. Typical applications which require strongly a local mesh refinement within a p‐finite element mesh are, e.g. the approximation of high gradients and the determination of contact areas. Numerical examples demonstrate the efficiency of the pNh‐element technique for such problems.

This paper gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The bibliography at the end of the paper contains more than 1330 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1999–2002.

Accuracy and time consumption in numerical computations are often in contradiction to each other. In modern industrial design processes flux field computation becomes more and more important. Thus, it is desirable to minimize any methodical error for better performance. This paper discusses a flaw of frequently used standard elements in boundary‐element‐method and shows a way to avoid it.

Stability characteristics of two‐level, time‐integration algorithms are investigated, with particular reference to explicit schemes. Conditions for stability are expressed on the basis of algebraic estimates of the eigenvalues associated with the amplification matrices of the algorithm. The use of automatic symbolic manipulators allows an extension of these estimates to higher order and multidimensional elements. Eigenvectors are also evaluated algebraically and the resulting fundamental mode shapes are related to the onset of instabilities.