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AbstractA quantitative evaluation of athletic training is one of the most important issues in the sports science, and its optimization problem between fitness and fatigue has to be considered. Although fitness is the gain of athletic training and athletes can acquire extensive fitness by hard training, they cannot continue such training for a long time because of fatigue. After the hard training which exceeds the physical capacity of athletes, a delayed onset muscle soreness (DOMS) appears and they cannot continue the same training hereafter. Because DOMS impedes the progress of training, it must be avoided when the training plan is made. By continuing training for a long period, the performance capacity of athlete body has enhanced and they can endure hard and long training with which it could not tolerate before, and such performance capacity enhancement is called supercompensation. In a planning athletic training, its optimization problem between fitness and fatigue should be discussed considering, both DOMS and supercompensation by forming probabilistic models of fitness and fatigue, optimal training plans which maximize the total fitness during training periods and minimize the occurrence of DOMS are discussed analytically and numerically. 相似文献
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Naoya Osawa 《Researches on Population Ecology》1989,31(1):153-160
Summary Sibling (cannibalism among siblings) and non-sibling cannibalism (cannibalism among non-siblings) were studied in a natural
population of a lady beetle,Harmonia axyridis
Pallas.
Of all the eggs laid (n=2269), 24.76% (n=562) were killed by sibling cannibalism and 36.10% (n=819) were killed by non-sibling cannibalism. Sibling cannibalism occurred constantly and intensively in most egg batches
throughout the entire oviposition period. On the other hand, non-sibling cannibalism was more intense in the middle and late
oviposition periods, and when the egg batches were close to an aphid colony. This may be due to the high density ofH. axyridis larvae relative to aphid density in the middle and late oviposition periods and also the larvae searching intensively near
an aphid colony. 相似文献
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Sibling cannibalism in the ladybird beetleHarmonia axyridis: Fitness consequences for mother and offspring 总被引:1,自引:0,他引:1
Naoya Osawa 《Researches on Population Ecology》1992,34(1):45-55
Summary The adaptive significance of sibling cannibalism was analyzed in the ladybird beetleHarmonia axyridis at two prey densities. Possible costs and benefits were considered from three points of view: the mother, the cannibal and
the victim. Cannibals ate both infertile and fertile eggs, thereby increasing in body length and survival rate with the intensity
of sibling cannibalism. The cannibalistic trait was clearly beneficial to the cannibal when aphid density was low. However,
it was not always beneficial when aphid density was high and the victims were full siblings. The altruistic behavior of being
a victim was beneficial only when the victim was cannibalized by full siblings at low aphid density. The mother attained almost
equal fitness at low aphid density, regardless of the intensity of sibling cannibalism. This suggests that sibling cannibalism
is not maladaptive for the mother. At high aphid density, however, mother’s fitness decreased with the intensity of sibling
cannibalism, indicating that sibling cannibalism is maladaptive for the mother when larval food availability is high. 相似文献
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In this paper, we consider the multivariate normality test based on measure of multivariate sample skewness defined by Srivastava (1984). Srivastava derived asymptotic expectation up to the order N−1 for the multivariate sample skewness and approximate χ2 test statistic, where N is sample size. Under normality, we derive another expectation and variance for Srivastava's multivariate sample skewness in order to obtain a better test statistic. From this result, improved approximate χ2 test statistic using the multivariate sample skewness is also given for assessing multivariate normality. Finally, the numerical result by Monte Carlo simulation is shown in order to evaluate accuracy of the obtained expectation, variance and improved approximate χ2 test statistic. Furthermore, upper and lower percentiles of χ2 test statistic derived in this paper are compared with those of χ2 test statistic derived by Mardia (1974) which is used multivariate sample skewness defined by Mardia (1970). 相似文献
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有田直矢 《南京大学学报(哲学.人文科学.社会科学 )》2000,(2)
郑家屯为辽源县 (今双辽县 )县治所在地 ,具有相当重要的交通和战略地位。1 91 6年 8月 1 3日 ,在此地爆发了中日两军的武装冲突事件 ,史称“郑家屯事件”。对于中日两国来说 ,该事件均是在国内情况极为“微妙”时所发生的。从两国社会政治的“微妙”背景来分析该事件及其外交谈判 ,就可以看出当时中日关系极为重要的转变。 相似文献
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