In the outskirts of Tôkyô the woods surronnding the houses are one of the most conspicious parts of the landscape of settlements there. These woods serve as protection against prevailing winds. The author's investiga-tions of them from aero-photographs taken by the Military Survey Depart-ment may be summarized as follows
1) Varieties of wind-mantles. Of the large variety of wind-mantles, the trees-that predominate are the Keyaki (Zelkowa serrate), the arder (Alnus japonica, Anus tinctoria) and the oak (Quercus acute, Querczus mnyrsinaefolia). Their distribution is determined both by their ecologies and environments. Figs. 3-II show their directions, forms, and density, and Fig. 2 their distribution.
2) Density of wind-mantles (Fig. 14). The density of the wind-mantles is not proportional to the wind velocity (Table I) . While the present per-Icentage of houses with wind-mantles to the total number of houses varies, 70% may be considered as the proportion for all the settlements before the region developed. The percentage naturally diminishes as the region develops.
3) The directions of alignment of the wind-mantles (Fig. 21). The frequency in direction of the shelter-belts (wind-mantles) is generally smaller E-W, and larger N-S (Fig. 20). The same tendency is also seen in the wind directions observed at some stations (Fig. 16-18). The next dominant direction is southward. Fig. 15 was drawn in consideration of the fact that the shelter-belts face the three directions, SW, S, and SE. It shows the density of the shelter-belts to the south and also the area affect-ed by southerly winds (Fig. 22). It will be seen from this map that the area of high density is usually southward.
If the directions of the shelter-belts agree with those of the prevailing winds, then the latter could be found from the alignment of the shelter-belts. Fig. 22 shows the directions of the prevailing winds, which were taken into consideration in the above mentioned method, and which also agrees with observations made at certain stations and from the experience of local residents. While it is true that the alignments of the belts are influenced by the topography, the author thinks that they may be influenced by other conditions as well.
This study was made under the kind guidence of Prof. Tsujimura.

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The inclination and yaw characteristics on the recovery ratio of a temperature probe at high subsonic speeds were investigated experimentally and the following results were obtained.
(1) The recovery ratio may be taken constant within yaw angles of |θ|≤20°.
(2) The recovery ratio may be taken constant with inclination angles at the low Mach number, but it is influenced by inclination angles at the high Mach number.
(3) In the case of a small inclination angle (|α|≤15°), the flow properties normal to the probe axis can be calculated with a reasonable accuracy by using the recovery ratio of zero inclination angle.

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This paper describes studies on wind-duration of strong wind, which is one of the factor for analysing fatigue damage of structures sujected to repeated wind load. In this paper, observed wind data, which is record with duration 72 hours at the center of which annual maximum wind speeds occurs, were used to estimate duration and probability of wind velocity. Generalized probability distribution function of wind velocity were proposed. Duration of strong winds presented as a function of its maximum wind velocity. From these results, multipling generalized probability distribution function by generalized number of (wind velocity) samples, approximate equation of wind-duration was derived. Approximate equation of wind-duration proposed in this Papers useful for analysing fatigue damage of structures under strong wind in Japan.

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It is well known as an observational fact that every locality has a proper surface wind direction of the maximum frequency on account of the peculiar topographic effect. Hence the angle between the directions of surface and gradient wind is always subject to a considerable fluctuation accompanied by the change of gradient wind direction. As an extreme case of such a procedure we can imagine an oblate Ekman's spiral. In this case the fundamental equations of motion based on the principle of vorticity transport are, in customary notation,
We put here
then we readily see that the eddy motion is stable or unstable according as
Thus the critical state is characterized by the relation 2a²=1.
Adopting Dobson's observation numerical computation has been performed and we see that the result once published by the present author obeys this stability condition.
Next the thermal stability of atmosphere is discussed. According to the usual conception the stability of atmospheric stratification is determined by the lapse-rate of temperature and it is stable or unstable according as the lapse-rate is lower or higher than the adiabatic lapse-rate.
But this is not always the case with the recent aerological observation so far as it concerns the lower atmosphere of 1 kilometer level, even if the atmosphere is considerably stable as revealed out by the observation of cloud form in the lower stratum.
Namely we often find the case of super-adiabatic lapse-rate in which the stratification is comparatively stable.
As one plausible explanation of this fact the theory of the thermal stability of viscous fluid has been applied and the recent study of A. L. Hales also supports this view.

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Since the wind load is critical for the design of transmission lines, it is important to assess the design wind speed reasonably at construction sites. Wind loads acting on the transmission tower usually vary greatly by direction because of the structural characteristics. However, in the current design method of transmission towers, non-directional basic wind speed is applied in Japan, and therefore in many cases this may result in overestimation. In this paper, a method to estimate directional basic wind speed for the transmission tower design is proposed. The return period of the directional wind speed is estimated keeping the same non-exceeding probability of occurring stresses as the current design method. Then directional basic wind speeds at meteorological stations are determined by comparing with the typhoon simulation results.

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近年では気象観測データと台風シミュレーションを用いた建設地点での特性を考慮した風荷重の評価が進められている。この場合，建設地の毎に対応した合理的な設計風速を用いており，別の風力相関の問題が重要となる。本報では，建物に作用する風力のによる影響を検討するため，多量の風圧データを用いた風力の別相関特性，柱に作用する最大軸応力度を基にした風荷重の組合せ効果の別検討結果を報告する

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The developed sampler is examined for measuring out suspended dust to the north, east, south and west winds in measuring period. This sampler is constituted of the four usual samplers, a wind-vane and switch auto-changer replying to the each wind direction. And it is able to separately catch suspended dust on the each filter for the different wind blowing by the developed sampler.
The suspended dust concentrations were five times measure using the developed sampler and the usual sampler at Toyohara Cho in Hiratsuka City for about fourty days from August to September in 1979. And Iron, Lead, Manganese, Vanadium, Titanium, Chromium and Nickel in the caught suspended dust were determined by the Fluorescent X-Ray Spectrometry method.
The concentrations of suspended dust and each metallic element measured by the developed sampler were compared with the value obtained by the usual sampler showed good agreement. When the wind blew from the east or north at the sampling site, the concentrations of air pollutants were shown the maximum affecting the industrial and urban area. On the other hand, the low level concentrations were shown in blowing southerly or westerly from the seaside and the rural country.
Within the results of this study, it was able to suppose the source of suspended dust and each metallic element by the developed sampler and this sampler was very useful.

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　中高層建物では屋上に

風速計を設置する場合が多いが、適切な設置位置をまとめたガイドラインは無い。中高層建物屋上では非定常性の大きな気流場が形成されるため、屋上で外部風速が適切に測定されているとは限らない。本研究では屋上直上での水平断面の気流場に着目し、測定・風速と外部・風速との差を風洞実験及びCFD解析により評価する。本報では、風洞実験により外部をパラメータとしてPIV によりを面的に測定し、外部との差を算出することで外部判定精度を評価した結果を報告する。

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本論文では、変化時の三次元角柱の風圧特性を明らかにすることを目的とし、変時の角柱まわり流れのLES解析を行った。変化の度合いによって、隅角部の近傍に極大な負圧が認められた。また、その際のと流れ特性との関連性について考察した。
を緩やかに増加させた場合、前縁付近の剥離・再付着流れから、剥離せん断層が後方で巻き込む流れへ移行するが、ある程度の速度で変化させた場合は流れの移行に対して変化が速いため、逆方向のになっても側面に強い循環が形成続け、主流に対して流れが大きく曲げられるため、極大負圧が生じるものと考えられる。

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鉄道分野での強風時運転規制方法の更なる最適化のために、著者らは１点の風速計で得られた風速を簡便に推定するモデルについて研究している。強風時の風速データを用いて２地点の風速およびの相互相関関数を調べた。その結果、強風時ののほうがラグの増大に伴う相互相関関数の減少率が大きかった。

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本研究では中高層建物の屋上近傍気流の水平断面に着目し、建物屋上部における外部

・風速計設置想定位置における・風速の測定結果と外部・風速との差を風洞実験及びCFD 解析により評価を行い、適切な風速計設置位置の提案を行い、その後自然換気口の高度な制御手法の提案へと繋げることを目的とする。本報では、風洞実験を再現したLESにより、外部・風速との差の評価・計測位置の検討を行った。

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本稿は風雑音に見られる低周波帯域の相関から，マイクロホンアレイに到来する風の

と風速を推定し，風速計の実現可能性を検討した。まずマイクロホンアレイが収録する風雑音をシミュレーションで作り，風速の推定が可能なことを示した。次に三つの近接マイクロホンで扇風機の風雑音を収録し風速を推定した。結果，推定値はに依存した。そこで推定値と真値の組を用いて誤差の低減を試みた結果，の誤差は約6.64°風速の相対誤差は約5.4%まで低減した。また，マイクロホンが収録する周囲の雑音の影響を検討し，風速3.5m/sに対しA騒音レベルが70dB程度の雑音では推定に影響がないことが分かった。

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自然風における変動を再現することを目的として，圧力勾配方向の制御によってを変動させることができる風洞試験装置を試作した．風路の開閉を手動で行っているため，変化時に風速も変動するなどの問題が生じているが，概ね計画どおりにを変化させることができた．

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