This paper contains a three-dimensional solution for the stresses and deformations arising in an elastic circular cylinder with a spherical cavity under transverse bending. The method used here is based on Dougall's stress function approach referred to the cylindrical and spherical coordinates. The problem can be reduced to one of two simply connected domains, i. e., an infinite circular cylindrical region and an infinite region excluding a spherical cavity. The two stress functions in each region are given by simple expressions of the cylindrical and spherical harmonics. The boundary conditions on the surface of the cylinder and of the spherical cavity are satisfied by using the relations between the cylindrical and spherical functions. Numerical results are given for five different radii of the cavity.

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In this report, the phenomenon of torsional stress wave propagation in a conical bar is investigated based on the dynamic theory of elasticity. And the following results are obtained. At the wave front, the shear stress distribution has the same form as that of the torque applied, and the amplitude of the stress is inversely proportional to the distance between the apex and the observed point. The torque is transported only with the fundumental wave of which the shear stress distribution has sinusoidal form. Some time after the front passes away, it is permitted to replace approximately the transverse shear stress by that of the fundamental wave, however, complicated the stress distribution of the applied torque may be. As the apex angle becomes small, the degree of approximation becomes good.

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Many theories of residual stress measurement have already been proposed for plate and cylinder, but only two methods such as the mechanical method by Kawaguchi and the specific volume method by Yonetani are published for a single-layered sphere. In this paper, the authors propose a general formula to calculate residual stresses in a multi-layered sphere by a new method using X-ray, and the formula of industrial use for a single sphere is shown to be reduced to a special case of general one. As the linear expansion coefficient of each spherical layer is different in a general multi-layered sphere, residual stress distributions are affected by thermal stress due to temperature change, so that the authors show also a stress compensating formula for temperature. Finally the authors give two examples of residual stress measurements by applying their new method to chromium deposited steel spheres (SUJ-2) which have been quenched and tempered in different conditions.

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As a chain has a comparatively large mean line density as well as a high modulus of elasticity for elongation, the linear theory assuming the constant tension during vibration is hardly valid. Therefore, when a roller chain containing link plates of an arbitrary shape is used in operation with a rather small tension with an arbitrary angle to the vertical direction, the temporal fluctuations of tension during vibration and the spatial variation of tension along the longitudinal direction seem to have a remarkable effect on the frequencies and the modes of natural vibration. The authors have analyzed the effect theoretically by regarding particularly the chain stretched vertically as a system having multple degrees of freedom. The authors have applied the method of separation of the variables to analyze the effect of the temporal fluctuation s of tension and used the perturbation method to analyze the effect of both the temporal fluctuations and the spatial variation of tension. In these analyses, the typical hard spring type characters of the resulting nonlinear vibrations have been confirmed.

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The author computed bispectra of experimental output data passed through a nonlinear asymmetrical system and those obtained from model simulation to judge whether the nonlinear model fits or not. Then a function was introduced, which was defined as the ratio of the bispectrum and the tripple product of the square roots of the power spectra of the related frequency components and was tentatively called "the skewness function" for expression of the dependence of phase properties among those frequency components. Moreover, the properties of the skewness function both for artificial Gaussian and non-Gaussian signals was investigated. It becomes clear by this research that we can practically compute bispectrum and skewness function, identify the peculiarity in non-Gaussian wave-forms by the bispectral information, and utilize it to improve nonlinear modeling technique.

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This paper deals with a concrete design procedure of a two-dimensional model control systems which particularly serves to control the bending vibrations of elastic plates. Besides, the influence of spatial deviations in the driving force distributions upon the system response is considered from the viewpoint of the model domain. The method is applied to the control problem of flat plane speakers, which are suitable to reproduce bass sounds in acoustic systems. Two kinds of control systems for plane speakers are designed taking account of the lower four and nine modes among innumerable eigenmodes which disturb the uniform vibrations of the plates. The dynamic characteristics of the systems are experimentally investigated. The results show the practical usefulness of the method

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A part load performance of gas turbine heat recovery system is analyzed from the standpoint of the second law of thermodynamics, using as the parameter a function of exergy. The characteristics of gas turbine at part load are estimated from the design point data and heat rate about some gas turbine. In this system, additional fuel supply to heat recovery boiler is made to meet the heat demand which exceeds the exhaust heat from gas turbine. The effect of additional fuel supply and the irreversible losses occurring in each process of the system are described.

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The metallic friction between a hard rough and a soft smooth surface has been investigated, in which the scratching of the soft surface by the hard asperities and the transfer of soft metal to the asperities could occur. Two effects of the metal transfer on the friction were found in the frictional experiments between low carbon steel and copper surfaces. One is an increase in the shearing component of the friction resulting from the sliding between softer metals, i.e., copper and copper. A second phenomenon due to the metal transfer is an increase in the cone angle of the hard asperities which could be assumed to have conical shape, and this causes a reduction in the ploughing component. The friction force could be evaluated from the height distribution of the asperities on the rough surface and the height of front ridge formed in front of the asperities, where the two effects of the metal transfer on the friction were also taken into account.

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Cutting mechanics at the initial stage of peripheral milling is precisely discussed on the basis of many data on various factors. Experiments carried out are measurements of cutting force and its vector representation, observations of chip formation process with microphotographs, and measurements of the stress distribution and chip contact length on the tool rake face and shear angle obtained from the chip thickness. Main conclusions are the followings. (i) A transient period exists at the initial stage, where some factors to be effective on the mechanics vary with violence. In the period, up milling process and down milling process represent their characteristic feature. (ii) The transient cutting mechanics changes its feature with tool advancement. Up milling has four processes which can be distinguished in a period from the first contact of tool with workplace to the steady state. Down milling has two processes. The mechanics of the above each process is discussed with experimental data.

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