In this study, to optimize the conditions for print out by the printer, which means color reproduction, was estimated by the parameter design method of quality engineering. RGB of ISO/JIS-SCID standard image S7 was applied as the signal factor, and RGB of the printed image measured as characteristics of output. The resolution of the scanner and the quality of paper was selected as noise factor. Various settings of the printer were decided to control factor. Analysis of variance on the RGB data and SN ratio shown that the effect of "Adjustment of image quality" and "Print mode" were significant among the main effect of control factors.

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Curved shells have been widely used in the field of building construction and vehicle body. In the other hand, composite materials (fiber reinforced plastics:FRP) are used for lightweight design. Since FRP materials have different elastic properties depend on the fiber-directions, the vibration characteristics show complex phenomena. In this report, the first, the natural frequencies and natural modes of the slightly curved FRP curbed shells formed with angle play are estimated based on the shallow shell theory and the Ritz method. The next, the influence of fiber-direction and eccentricity of curved plate on the natural frequencies and natural modes are discussed.

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An analysis for damping of shallow shells with a constrained viscoelastic layer and metal layers is presented. In this paper, vibration damping properties of three layered shallow shells are analyzed by SEM (Strain energy method). Eigenvalue and eigenvector (displacement functions) are analyzed based on the Ritz method, when natural frequency, modal loss factor and strain energy are obtained. The modal loss factor is defined as a ratio of damping energy (strain energy consumed in viscoelastic layer) dissipated during a vibration cycle and total strain energy of the shell. For numerical examples, damping energy distributions in the core are presented, and the concept of effective damping patch design are considered.

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The finite element method is applied to the nonlinear buckling analysis of laminated composite conical shells. The coupling effect of general laminates is considered in the stress-strain relation. The displacement field within each element is represented by Fourier circumferential components. The effects of axisymmetric initial imperfection on the buckling load of antisymmetric angle-ply laminated conical shells are investigated.

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This paper presents the optimization for nonlinear vibration of laminated composite, circular cylindrical shells by using Multi-Objective Genetic Algorithm (MOGA). For this purpose, a backbone curve equation for primary resonance of the shell is first derived from nonlinear vibration analysis using the harmonic balance method analytically. In optimization, fiber angles for each lamina of a symmetrically balanced laminated shell are taken as discrete design variables, and then nonlinear natural frequency and linear natural frequency are considered as object functions to be maximized. In numerical calculations Fonseca-type MOGA is employed for the present problem and parete optimum solutions are obtained. Finally optimal stacking sequence of the shell is studied by considering both of the linear vibration and nonlinear vibration characteristics of the shell.

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A layerwise optimization approach, developed for the design of the vibration of laminated rectangular plates, is extended to apply to symmetrically laminated, composite skew plates. There is little information available on the optimum lay-ups of such skew plates, despite their extensive use in the aerospace industry. The optimum design problem is formulated to maximize the lowest frequency or the difference of the lowest two frequencies, and fiber orientation angles in the layers are used as the design variables. A Ritz method is used to calculate natural frequencies of the skew plates and the convergence and comparison studies with results available from the literature indicate accuracy of the calculated frequencies as the object function. An extensive set of numerical results is given in tabular and graphical form, illustrating the optimum lay-ups of the laminated skew plates with respect to the fiber orientation angles.

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In this research, effects of axial inertia force on nonlinear bending vibrations of a beam with a tip mass spring are analyzed. Although the added mass at the end of the beam decreases the natural frequency of the longitudinal vibration, vibration of the beams have been analyzed disregarding the inertia force in the axial direction. First, analytical procedure of the vibration of the beam is derived including both effects of the axial inertia force and the geometrical nonlinearity of the beam. Next, results of natural frequency of the beam are presented and effects of the axial inertia force are inspected. Finally, frequency response curves of the beam are obtained by the harmonic balance method and influence of the axial inertia force is examined.

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A finite element analysis is performed for a flex spline of a wave drive gear. Edge displacement is given so as to element lengths are unchanged in static analysis. Radial displacement by the rotation of the oval is expanded up to sixth order in dynamic analysis. The displacement in dynamic analysis depends little on the input rotation speed, whose form is largely different from that in static analysis. The displacement at side is small compared with in static analysis. Higer order displacement is significant at the center of side compared with at edge.

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A piezoelectric speaker has some strong points compared with a dynamic speaker. It is easily made small and light due to its simple structure. Also, it is excellent in sound reproduction in the middle and higher frequency ranges. But it also has some weak points. For example, the sound pressure level in the lower frequency range is poor because of the amplitude of vibration being small. Up to now a great effort has been made to improve the performance of the piezoelectric speaker, but no definite solution has been found yet. In this paper, a piezoelectric vibrator unit with a conical shell structure is reported, and the vibration and acoustic characteristics are discussed through F.E.M. and B.E.M. analyses and experiments.

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An approach has been proposed for the modification of a snowboard. The proposed approach consists of the snowboard turn simulation and the inverse analysis method (sensitivity analysis). Firstly, the outline of the numerical approach for the analysis of a snowboard turn is described. Subsequently, the sensitivity analysis is shown to estimate the change quantities for the modification of the snowboard. Finally, a prototype snowboard is modified by tuning the width and thickness of the snowboard into an objective snowboard referring two indices of the snowboard turn, a "Locus of center of gravity" and a "Rotation of snowboard". From the numerical examples, it follows that one can modify a prototype snowboard into an objective snowboard by using the proposed approach.

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