The general goal of this study is to construct the closed loop control system of the reattachment process in a backward facing step flow by a row of the vortex generator jets. It is necessary to examine the dynamic characteristics of the injection jet on the reattachment process in the design of the control system. The coherence and the frequency transfer characteristics between the injection jet and the near-wall flow in the reattachment region are examined in the open-loop system. The result shows that the coherence between the jet velocity and the surface static pressure is higher than that with the surface friction velocity and the surface static pressre has better characteristics of the frequency transfer gain at the streamwise station of X/H>7. A step response of the near-wall flow is also conducted in order to find transient characteristics. It is found that the damped oscillation occurs in the surface static pressure immediately after a step change in the jet velocity.

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The general goal of this study is to construct the closed loop control system of the reattachment process in a backward facing step flow by a row of the vortex generator jets. A row of injection holes which covers full span is located upstream of the step. Optimal conditions are studied experimentally by systematic variation of two parameters, injection hole pitch and jet velocity ratio. A micro wall flow sensor was used for measurement of forward flow fraction. It is found that the reattachment line is almost parallel to the spanwise direction in the range of the pitch of 10 d to 20 d, although the discrete disturbance by jet injection is provided at the step. The velocity ratio is one of the most effective manipulated variables in the control system of the reattachment process.

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ホルスタイン種乳牛における遺伝性横隔膜筋症の原因遺伝子の1つであるHeat Shock Protein 70 (Hsp70)遺伝子の変異が，第四胃変位発生の要因である可能性について調査を行った.北海道根室地区のホルスタイン種乳牛で，第四胃変位を発症し，整復手術を受けた495頭の牛を調査対象とした. 遺伝子型解析はPCR法により，変異ホモ型，ヘテロ型および正常ホモ型の遺伝子型に区分した. 結果は，変異ホモ型1頭，ヘテロ型59頭，正常ホモ型435頭で，変異型遺伝子頻度は0.0616で，第四胃変位未発症牛492頭の変異型遺伝子頻度0.0986に比べて有意に低かった. この結果より，第四胃変位発症とHsp70変異型遺伝子との関連はないことが示唆された.

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Vortex Generator Jets (VGJs) have significant effects on separation control. The longitudinal vortices generated by VGJs embedded in the boundary layer ware investigated experimentally. In this study, to understand the reasons why the vortices for T-shaped jet orifice case behave in a manner different from those for the circular jet orifice case, velocity measurements were carried out in various phases of issuing jets discretely (pulsed jets).The pulsed VGJs with T-shaped orifices make the separation control effective in contrast to the circular jet orifice case. The pulsed VGJs with T-shaped orifices promote the interaction between adjacent vortices, and the strong longitudinal vortices were generated in the region close to the lower wall. The different feature of longitudinal vortices between the T-shaped jets and the circular jets can be explained by considering the vortex behavior in each phase of pulsed jets.

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The phase-averaged characteristic of a single pulsed vortex generator jet which is injected periodically into a turbulent boundary layer is described. Detailed measurements of the three components of the velocity in the jet made by a hot-wire anemometer with the X-type probe show evolution of the longitudinal vortex in the jet. The pulsed vortex generator jet in the stable period has a similar longitudinal vortex structure to that in the steady one. Down-wash motion of the longitudinal vortex in the jet introduces high wall shear stress.

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The exhaust gas volume, which is a major factor of the air pollution, is changed by the driving modes of the vehicle. In particular, on the congested traffic flow, its influence is considerable and complicated. Therefore, to establish the method for estimating each mode of the traffic flow is the fundamental problem. Already we have developed a simple model on the free traffic flow. In this paper, we showed a model developed by expanding the former model, to estimate the driving modes on congested flow through some actual surveys.

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グレリン受容体は主に視床下部・弓状核および下垂体等で発現し、成長ホルモン（GH）分泌や摂食亢進作用を持つ「グレリン」の機能を発揮させる重要な受容体である。我々は、ウシ・グレリン受容体遺伝子全長（約 6.5キロ塩基対）の塩基配列をウシ 13品種で決定し、塩基多型の全容を明らかにした。1,285頭の黒毛和種後代検定牛集団を用い、本遺伝子の塩基多型と増体形質との関連性を検討したところ、5'UTRマイクロサテライト（（TG）_n）と nt-7（C＞ A）座位に有意関連性を認めた。この関連性を説明する仮説（“translational hypothesis”）を提案した。

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