学習者にとっての理解を容易にする目的で,垂直降下式放電記録ペンとターンテーブルを組み合わせ,等加速度直線運動の測定法を基礎として半定量的な測定が可能な測定装置を作製した.円板状及び矩形状の真鍮板を試料とし,試料の質量と試料の回転軸からの距離及び試料に与える力のモーメントを変えた場合について角加速度の測定を行った.角加速度が試料に与える力のモーメントに比例し,さらにに反比例する関係を利用して実験データの解析を行い,が試料の質量及び回転軸からの距離の自乗に比例することを精度良く計測できることがわかった.

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In the case where a ship runs in regular waves with turning manoeuvre, the rolling oscillation becomes apparently unsteady state due to the changes of the frequencies and angle of the encounter waves and can grow into large amplitude. In comparison with the case where a ship runs straight, it is so difficult for the operator of the ship to predict the heavy amplitude rolling that occurs in the condition that the encounter angle of wave changes in heavy sea condition. Therefore operators, especially of small boats, should manoeuvre the ships taking into account of this phenomenon to avoid the dangerous situation, but this theme has not been studied adequately in the past. In this study, we investigate the rolling motions that occurs on a fishing boat (180t) including consideration of turning manoeuvre by using numerical simulation assuming that the boat runs in regular wave. The result of this study shows some basic characters of rolling motion that occurs in turning manoeuvre, and some conditions for receiving the influences of the timing of rudder controlling. Additionally we consider the ways of manoeuvre to reduce the maximum amplitude of rolling motion and find some effective ways.

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To estimate the maneuvering hydrodynamic coefficients or construct the ship position control system, not only ship position but also motion must be measured with high accuracy. Kinematic GPS (KGPS) has an enough accuracy for such purpose. By using of more than three GPS antennas, six Degree Of Freedom motion at any points can be calculated from position data of these antennas. We carried out the experiment of KGPS using "KOJIMA" that is training ship. It is shown that the ship motion can be measured, and velocity, angular velocity, force and moment at the center of gravity are obtained. Then we derived the relationship between KGPS error and motion measurement error, and showed the notes for arrangement of antennas.

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本研究の目的は，一般的に行われている2 種類の後方宙返りの身体の回転方略を比較することであった．男子大学体操競技者9 名（身長：1.66±0.03[m]，体重：61.2±3.8[kg]，年齢：20.1±1.9 歳）を対象に，異なる離地高からのかかえ込みと屈身の後方宙返りを行った．身体重心まわりの角運動量，離地時の身体重心の鉛直速度，空中局面のの変化について検討した．その結果，の大きさは離地高によって調節され，の変化のタイミングは空中姿勢に応じて調節されていることが明らかになった．つまり，の変化と大きさが後方宙返りを成功させるための重要かつ方略的なパラメーターであることが考えられた．

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The procedure to obtain the current effects is shown here. Ship motion can be measured by using of kinematic GPS(KGPS), which has a high accuracy. Force and moment of current can be derived from motion measurement of ship as a difference between total force acting on ship and forces based on a motion and operation of rudder. We carried out the experiment of maneuverability and passing through the KURUSHIMA strait using KOJIMA that is training ship. Firstly we investigated a maneuverability of KOJIMA by free running test. Next we analyzed the effects of current inKURUSHIMA strait, which is compared with the effects evaluated from current velocity measured by Doppler sonar.

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懸垂運動の基本「蹴上がり」が動力学的に解析されている.体操の選手が鉄棒に懸垂した状態から,鉄棒の上に苦も無く一振りで上がる秘密は,身体のを最小値に移すタイミングの把握にある.そこでは角運動量の保存が成立する瞬間を利用して,最小の,最大の角速度を得た回転が行なわれていることが計算によって示されている.

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力学的エネルギーの実験用としてWilberforceの振り子を作った.その際,おもりの部分に黄銅でできた正六角柱を使用した.共鳴点をとるとき正六角柱のが必要となり,その大きさを求めた.それを正n乃角柱に発展させ,I_Z=1/6Mr^2(2cos^2θ+1)となることがわかった.尚,この論文では正n角柱のを求め,その結果をいろいろの例について示した.

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The torsional vibration of the shafting driven by the marine main engine is a mater of the utmost importance. When the frequency of periodic torque is equal to the natural frequency of the shafting, the amplitude of the torsional vibration increases. This frequency is called critical speed. In order to calculate the critical speed of a propeller shaft, it is necessary to know propeller inertia.
This paper describes the production of the experimental equipment excited by periodic torque. Propeller inertia could be calculated from the experimental results.
Propeller inertia obtained from the experimental results is compared with it from the measurement of dimension.

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巨大な円板を有する回転軸の危険速度について検討し,柔支持領域でばね定数の低下と共に値の減少する危険速度が前向きふれまわりに限って1個のみとなる条件を導いた。これは軸全体の極より大きいことに対応している。限界条件近傍では前向きの二次危険速度はジャイロ効果のため円板位置での傾きが制限され弾性モードとなる。

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Recently, minimum time berthing problems have been numerically solved, however, a detailed ship motion model is necessary to obtain an optimal solution. To obtain the detailed model, detailed ship data by tank test when ship is designed, is needed. These detailed ship data are difficult to obtain a ship's captain or pilot. Therefore, it is difficult to obtain the solution of minimum time berthing problem for a ship's captain or pilot. In this research, the estimation of the ship motion model is tried from ship's principal particulars, which mariners can easily acquire. However, the model estimated from ship's principal particulars has possibility to include error margin. Therefore, in this research, it is tried to use the neural network controller to correct the minimum time control solution, which contains the model error. Using a small training ship, the validity of the estimated model and the neural network controller are examined by actual sea tests.

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