Biomechanical Study On A New Crouching Start (Chen\u27s Start)

スタートは、陸上競技の短距離走種目にとっては非常に重要な一部分で, 成績に大きく影響を与えるものである。今迄, 短距離走の技術に関する研究では, スタートに関するものがかなり多く, とくにスタート時の銃声に対する反応の速さ、スターティング・ブロックに加える蹴りの強さ、また、前後の足の位置とスタート時におけるそれぞれの足の蹴りの強さ、動作時間の速さなどの比較研究や、スタートの直後の歩幅の問題、前傾角度の問題、加速の問題、胴体及び四肢の位置の問題などが、重要な課題とされて来た。本研究は陸上競技のスタートを基本から変え、より合理的なスタートを可能にさせるため、工夫したものである。現在使用されているスタートは一般的に「用意」の号令で腰を高く上げて、両足で軽くスターティング・ブロックを蹴り、号砲 (銃声) に従い走り出すものである。本研究が用いた新しいスタートの方法は、「用意」の号令時から、スタートの号砲が鳴るまでの間に、前の足の蹴りに対し、後の足が引くことによって、前の足のキックの水平方向の力を強化し、更に、両手への「用意」時の体重負担を大きく軽減させ、従来のスタートよりも素速く、低い前傾姿勢でスタートすることが出来るように改良されたものである。This is the biomechanical study on a new crouching start (Chen\u27s start). Eight university decathlon athletes were asked to use the two different kinds of start (conventional and Chen\u27s). Studies were done by recording the EMGs of the lower extremities\u27 muscles and the forces both during "set" position and at the time of start, by filming from the "set" position to about three steps after the sound of the starting gun, and by timing and recording performances of the 30 meters dash with three trials for each start. The new start reduced performance time by 0.029 second. Pressure on hands were reduced from 27.50±2.87kg in the conventional start to 21.79±2.78kg while using the new start (p<0.01). The peak horizontal force in the front leg was increased in using the new start, from 78.55±9.16kg for the conventional start to 86.66±10.94kg (p<0.02) for Chen\u27s start. EMGs appeared during the time of "on your mark" and "set" position were changed both in pattern and in amplitude. In using the new start, the thrust force of the pre-tensed pulling rear leg in the "set" position were increased, the Length of the first step was greater and the angles of forward inclination of the body were lowered for the first few steps

(40(2):133-144)A study on the Tractor-mounted Peanut Harvester

為促使落花生收穫作業機械化，農試所著手開發一種曳引機承載單畦牽引式落花生收穫機。此種收穫機之特殊設計為莖蔓切割機構和振動犁。此機之作業方式為利用切蔓刀自主根切除花生莖蔓，以振動犁挖掘花生莢，再利用輸送鏈條清潔雜物。此機型設計時特點為結構簡單，成本低廉，容易操作，經局部調整可適用其他淺根類作物之收穫工作。A single-row, tractor-mounted peanut harvester capable of harvesting peanuts was developed by researchers at the Taiwan Agricultual Research Institute. The vine-cutting mechanism and vibrating plow were the specific designs of this equipment. This machine cutted the vines from the taproot digged it from the ground by vibrating plow, and then seperated and cleaned soil debris from the plants using conveying grid-chains. The simplicity, low cost and easy operation were the characteristics of this machinery. This equipment can serve as the universal harvester for shallow root crop harvesting with minimum modification

(38(1):140-155)A Study on the Performance of an Impact Type Peanut Thresher

落花生收穫機開發時所遭遇的瓶頸在於脫莢機構之改良。在此研究中，以打擊式脫莢機構進行落花生脫莢性能之測定，由試驗結果顯示，作業方式之有關流量和投入方式對於脫莢性能並無顯著影響，作物含水率的影響則十分顯著。切蔓處理後的花生植株可顯著降低破莢率。承網與脫莢筒間隙減少時亦可降低破莢率。脫莢筒轉速的增加亦增加破莢率。 The bottle neck problem in the development of a peanut harvester is the design and improvement of threshing mechanisms. In this study, the threshing performance of an impact type peanut thresher is analyzed. The results indicate that the feed rate and feeding type have no correlation with the threshing performance. The moisture content of peanut pods significantly affect the amount of damaged pods. Vine-cutted peanuts have the lower percentage of damaged pods. The reduction of clearance between concave and cylinder also decreases damaged pods. The increase of cylinder speed causes more damaged pods

Glucose Intolerance and Hypoxia in Tibetan Highlanders : Review on Verification of Diabetes Acceleration Hypothesis

特集2: 総合地球環境学研究所「高所プロジェクト」特集 = Special Issue 2: The High Altitude Project in Research Institute for Humanity and Nature本稿は, 高所プロジェクトの提唱してきた「糖尿病アクセル仮説」の一部について検証した科学論文 (Glucose intolerance associated with hypoxia in people living at high altitudes in the Tibetan highland. BMJ open 2016) のレビューである。耐糖能障害がライフスタイルと低酸素血症といかに関連するかを, 中国からインドにわたるチベット高原 (2900-4800m) の1258人の住民において研究された。社会経済的要因, 高度3500m 以上在住, および低酸素血症が, 高所住民の耐糖能異常の増加に大きく関与していることが報告された。低酸素血症, 多血症, 耐糖能異常の3者には密接な関係があり, 加齢とライフスタイル変化がその関係を促進している (糖尿病アクセル仮説) ことが検証された。The association between glucose intolerance and high altitudes (2900-4900m) was clarified in Tibetan highlanders. The hypothesis was verified that dwelling at high altitudes have vulnerability to diabetes accelerated by lifestyle change or aging. 1258 subjects (40-87 years) were examined; farmers in Domkhar (2900-3800m), nomads in Haiyan, Ryuho, and Changthang (3000-4800m), and urban dwellers in Leh and Jiegu (3300-3700m). The prevalence of glucose intolerance was higher in urban dwellers and in farmers compared with nomads. Dwelling at a higher altitude was significantly associated with fasting hyperglycemia (odds ratios for >4500 and 3500-3999m were 3. 59 and 2. 07 vs 1.0 ; <3500m) by multiple logistic regression analysis with adjustment of age, sex, and confounding factors. Further hypoxemia and polycythemia were closely associated with glucose intolerance. Socioeconomic factors, hypoxemia, and the effects of altitudes over 3500m play a major role in the high prevalence of glucose intolerance in highlanders. Tibetan highlanders may be vulnerable to glucose intolerance, with polycythemia as a sign of poor hypoxic adaptation, accelerated by lifestyle change and aging