Problems related to influence of wind on sprinkler sprays are wind drift, amount of evaporation loss, variation in the sprinkling region, etc. As a consequence, geometric pattern form is influenced by these effects directly. The wind condition near the earth's surface is turbulent flow and vary with time. On the other hand, the author introduced the concept of mean wind velocity and theoretically calculated the geometric pattern form of a single sprinkler. Some of the calculated data were compared with the experimental data and the accuracy of the theoretical calculation were confirmed.
1) On flat field
a) On the assumption that the wind velocity is the same as the average wind, the author considered the case of a velocity profile according to logarithmic law.
b) Previous calculated data were used for the calculation of the geometric pattern form of a single sprinkle on flat field under a windy condition.
c) The calculated geometric pattern form shows a shift to the wind direction according to the wind speed.
2) On inclined field
a) On the assumption that the wind velocity is the same as the average wind, the author considerd a case of. uniform velocity distribution.
b) The wind direction is assumed to be parallel to the earth's surface and the x direction. And, the following equations are obtained in the x, y and z
directions:
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c) The calculated results show the characteristic geometric pattern form of a single sprinkler on an inclined field under a windy condition.

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In order to obtain uniformity of sprinkler irrigation on inclined field, the author derived some factors required for this purpose by appling the results of theoretical calculation on the trajectory of flying water droplets of various diameters projected from a sprinkler nozzle. A special sprinkler was designed to determine the theoretical data. As a result, the following two methods are considered as means for uniform distribution of water on inclined field.
a) Method of controlling the angular velocity of a rotary sprinkler according to discharge direction. By this method water concentration at the upper part of inclined field is improved and the mean depth of sprinkled water in any discharge direction becomes uniform.
b) Method of varying the nozzle angle of a sprinkler according to the discharge derection to get uniform water distribution. By this method the nozzle angle can be set so as to make the flying water droplets of the same diameter fall at an equal distance in any discharge direction on inclined field, so that the same geometric pattern as on the flat field can be obtained.

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In Tube-end Spinning, “softening” of tube material with frictional heat generated at interface between die and tubular stock, is considered as the most important fundamental principle. And so, knowing about the forming temperature and effective heat to soften the tube material is required to discuss the formability for Tube-end Spinning. In this paper, the equation of mean temperature θ_m1 of material at forming portion, and effective heat Q₁ which is available for softening tube material during the forming are formulated. The results are written as below.
(1) The mean temperature θ_m1 increases according to the increase of die revolution and decreases according to the increase of the feeding rate of tubular stock.
(2) Effective heat Q₁ is proportional to the forming time and becomes larger according to die revolution increase, smaller according to feeding rate and die angle increase.
(3) Effective heat Q₁ is about 20-40% of total heat, and the amount of heat flowing into die is largest among of heat losses.

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Since nearly all sprinklers are sprinkling over circular areas, a certain amount of overlap is always necessary for uniform water distribution.
The degree of the uniformity of water distribution in the field can be expressed numerically by the index-Uniformity Coefficient (C_u) which is defined by the equation C_u=100 (1.0-ΣX/m·n).
This index is an important factor for planning and controlling the sprinkler irrigation system and has been evaluated from such experiments as the Pan tests and the Can test.
In this report, the authors propose a method of calculation to evaluate the Uniformity Coefficient from the distribution pattern formed by a single sprinkler and to use an electronic computer in order to process this calculation.
Then, an optimum spacing for a certain sprinkler discharge profile and an optimum sprinkler discharge profile for a certain spacing are studied by using this calculation technique.
These data and the proposed calculation technique may be very useful for the planning and control of a sprinkler irrigation system.

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いわゆる切込刃などの在来の刈払機用刈刃の欠点は, 短時間のうちに摩耗や刃こぼれを生ずることであり, 摩耗によって切断角が大きくなった刈刃は, 目立てしても切れ味が充分に回復しない。また, 刈刃の回転と作業動作に伴って生ずるジャイロ偶力が意外と大きく, これによる疲労の問題も無視できず, 安全性の点でも大いに問題がある。一方, ナイロンカッターは, 安全ではるが, 耐久性に乏しい。本報のピアノ線刃による草刈装置は, これらの欠点をいくらかでも除去しようとの意図から考案されたもので, 機構の主体は, ピアノ線刃を円盤周部の取付環に回動自在になるように取り付けたことにある。
本報では, ピアノ線刃の構成並びに諸元を決定するための実験を行い, 実用化の可能性を考察した。続報では, 高速度写真などによる, 雑草に対する切断特性を明らかにし, さらに作業者が受ける生体負担及びそれに関与する諸要因を調べた結果を報告する。

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