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A technique combining finite elements and boundary elements is promising for unbounded field problems. A hypothetical boundary is assumed in the unbounded domain, and the usual finite element method is applied to the inner region, while the boundary element method is applied to the outer infinite region. On the coupling boundary, therefore, both potential and flux must be compatible. In the finite element method, the flux is defined as the derivative of the potential for which a trial function is defined. In the boundary element method, on the other hand, the same polynomial function is chosen for the potential and the flux. Thus, the compatibility cannot be satisfied unless a special device is considered. In the present paper, several compatibility conditions are discussed concerning the total flux or energy flow continuity across the coupling boundary. Some numerical examples of Poisson and Helmholtz problems are demonstrated.

Materials with anisotropic conductivity are frequently used as sensors in electrical industries. In this paper, an anisotropic conductivity tensor to express Hall effect in n‐type semiconductors is derived and its steady‐current field is solved using the finite element method. Some numerical examples are given and comparison with measured data is discussed.

Ion‐acoustic wave propagation in plasma is discussed. Analytical and numerical solutions are given for one‐dimensional plane waves. The similarity of the ion‐acoustic waves to the waves associated with an electrical transmission line is pointed out and the solved examples are compared with experimental observations.

A numerical integration scheme using the Monte Carlo method is discussed to evaluate the singular integral in boundary elements. A numerical demonstration is given for some potential problems. Results evaluated by the Monte Carlo method are compared with the analytical ones for accuracy and computation time. Examination shows the validity and capability of the approach.

The two‐dimensional discrete Huygens’ modelling or TLM simulation is presented for the TE electromagnetic field problems. The TLM element or node with variable traveling speed and characteristic impedance is applied to several practical problems including scattering at the edge of a wall and over periodic grids or grooves, wave propagation along a dielectric structure, and a mode coupling between two parallel optical waveguides. The TLM solutions are compared with the theoretical ones or the results of other numerical methods and reasonable agreement is achieved.

What were the spinning industries like in the initial stage in Japan? From which class did the founders of these industries come, ex‐warrior or commoners (merchants or farmers)? This will interest readers. Viewed from a capital investment, it was most significant in Japan whether the government financed an industry or not. This article deals with Tanigawa Tatsumi, the founder president (presidency 1885‐1911) of Okayama Cotton Spinning Company (an enterprise for employing ex‐warriors). Whereas cotton spinning companies for employing ex‐warriors played an important role in the initial stages of the development of the cotton spinning industry, these became bankrupt before long. Under such circumstances, Tanigawa’s Spinning Company weathered many years. An examination of a brief history of Okayama Spinning Company with special reference to Tanigawa’s life history will reveal the significance of the entrepreneur’s learning and virtue, organizing ability, and leadership. Furthermore, it will make clear what otherwise might have been overlooked about the initial nature of industrialization in Japan.