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981.
In this study, we found that the optimum take-off angle for a long jumper may be predicted by combining the equation for the range of a projectile in free flight with the measured relations between take-off speed, take-off height and take-off angle for the athlete. The prediction method was evaluated using video measurements of three experienced male long jumpers who performed maximum-effort jumps over a wide range of take-off angles. To produce low take-off angles the athletes used a long and fast run-up, whereas higher take-off angles were produced using a progressively shorter and slower run-up. For all three athletes, the take-off speed decreased and the take-off height increased as the athlete jumped with a higher take-off angle. The calculated optimum take-off angles were in good agreement with the athletes' competition take-off angles. 相似文献
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Changes are being made in the content of presentday electrical engineering curriculums which require a fresh, modern outlook with regard to techniques pertaining to problem assignments and laboratory projects. Course content is being upgraded and broadened in the direction of a fundamental analytical approach. The recent revision of the electrical engineering curriculum at The Pennsylvania State University, University Park, includes liberal use of an ac network calculator in all electrical engineering options, which are outlined in this paper. The uniqueness of the ac network calculator at the University is that it is used exclusively for educational purposes, especially in the Department of Electrical Engineering. This paper discusses the "when, where, and how" of the utilization of this facility in the electrical engineering curriculum. 相似文献
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Robert P. Brady 《Counselor Education & Supervision》1976,16(1):74-76
In recent years it has been estimated that from 30 percent to 50 percent of the medical complaints brought to the family or general practice physician are functional in nature and may be psychosocial in origin (Harmon, Masuda & Holmes 1970). While chemotherapy may be appropriate for the patient with acute situational anxiety and psychiatric consultation may be appropriate for the severely neurotic or psychotic patient, the family practice physician has few remedies for the patient with chronic aches and pains, housewife syndrome, middle-age depression, businessman's fatigue, and a host of other quasimedical complaints. 相似文献