Ischemic diseases are lifethreatning and socioeconomically important in Japan. They are caused mainly from atherosclerosis with vascular stenosis. The atheromatous lesions are described briefly, for the specialist of flow dynamics and rheology to be able to understand the histopathology, developing mechanism and molecular biology, adding several discussions as to the flow and vascular problems yet unelucidated in modern medicine.

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The combustion is an extremely complicated phenomenon accompanied by several interactive processes such as chemical reaction, heat and mass transfer and gaseous flow. Therefore, the main stream of the combustion study has so far been the phenomenological approach based on experimental findings, and the contribution of the theoretical approach has been very limited. However, the recent remarkable progress in the asymptotic analysis is going to change this situation. The method was originally adopted in the late '30s by the Russian school, but its full power has been achieved only in the last two decades. In this report, the one-dimensional flame theory with simplified one-step kinetics will be explained, in the beginning, to show how the burning velocity can be given as an eigenvalue of the conservation equations. Then the asymptotic analysis will be introduced to obtain the analytical solution so as to illustrate utility and essential natures of the method.

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Weakly nonlinear equations governing the motions of internal waves for two-fluid system are derived using Zakharov's methods. The equations include all of the KdV, B-O and ILW equations, representing the evolution of the whole range of wave-numbers. Spectral methods will be applied directly to the numerical integration of the obtained equations.
Solitary waves with various depth ratis of two-fluids are numerically simulated. As a result, the ILW-solition produces tails in the rear as the depth ratio approaches to 1 and the KdV-soliton steepens its front as the depth ratio approaches to 0.

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The stable posture of two parallel circular cylinders in a uniform flow is experimentally studied when they are free to rotate in one about an axis in the middle between them.
The two cylinders come to rest arranging side by side to the oncoming flow when s/d= 0.5, where s is the distance between the axis of rotation and the central axis of the cylinder and d the diameter of the cylinder. When s/d-=1.0 or 1.5, the two cylinders are stable both in a tandem arrangement and in side-by-side arrangement to the oncoming flow. When s/d≥2.0, the two cylinders are stable only in a tandem arrangement.

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The life cycle of three-dimensional cumulus convection is numerically simulated by a large eddy simulation method using a one-equation model. The basic equations contain nine prognostic equations : the Navier-Stokes equations, pressure and thermodynamic equations, three moisture and water equations, and a model equation. The model equation is a transport equation for subgrid scale kinetic energy ; buoyancy and shear produce subgrid scale kinetic energy. A terrain-following coordinate transformation is employed in order to map a simulation domain with an irregular lower boundary onto a rectangular domain. A finite difference scheme solves the transformed equations, conserving heat, moisture, water substances, and subgrid scale motion. The life cycle of an isolated cell of cumulus convection is simulated over a bell-shaped mountain for a simplified atmospheric condition. The result is in good qualitative agreement with observed characteristics. A simulation is also made over a flat surface to investigate the effects of the mountain. For comparison, the mountain case is simulated using Smagorinsky's model. The overall level of subgrid scale kinetic energy within the cloud is less than that computed from the one-equation model. However, subgrid scale kinetic energy diffuses outwards the cloud.

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