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81.
甘蓝型油菜隐性核不育系绵 7AB -3中成对兄妹交不育株后代的不育率与相对应可育株自交后代的不育率相关分析表明 :不育株的不育率随相对应可育株自交后代的不育率高低而变化 ,可育株不育率高者相对应的不育株的不育率也高 ,反之则低 ,两者之间呈显著正相关 相似文献
82.
本试验的主要目的在于寻求母狐在不同日期配种和不同的交配时间对受胎率、受配率以及平均产仔数的影响。结果表明,4月上旬受胎率最高,为100％;3月中旬至3月下旬受胎率次之,为7679％,二者差异极显著（P＜0．01）;而3月上旬和4月中、下旬再次之,分别为66．66％和50％,与3月中、下旬相比差异又极显著（p＜001）。受配率则以3月中旬为最高,然后是3月下旬,而3月上旬和4月上、中旬较低。配种日期与平均产仔数无关。对于交配时间,受胎率则以30－60分钟为最高,为82.55％,与不足30分钟和60分钟以上比较差异极显著（p＜0．01）。 相似文献
83.
冰下水体沉积物中有机物、细菌及其耗氧速率的研究 总被引：2，自引：0，他引：2
冰下水体沉积物中含有丰富的有机质（１１．５％）和细菌（１２．７×１０７个／克）。其耗氧速率比春、夏、秋三季池塘底泥的耗氧速率低得多。沉积物中有机物含量与细菌数量和耗氧速率之间呈正相关。 相似文献
84.
In this article, the ruin probability is examined in a discrete time risk model with a constant interest rate, in which the dependent claims are assumed to have a one-sided linear structure. An explicit asymptotic formula is obtained for the ruin probability. Generalized Lundberg inequalities for the ruin probability are derived by martingale and inductive approaches. 相似文献
85.
In this article, the time from the start of chemotherapy randomization until cancer relapse is of primary interest. Here, cancer relapse refers to the appearance of the first observable malignant clone after therapy. A dynamic model for cancer relapse after chemotherapy is developed. The model differs from the traditional cure rate models in that it takes into consideration the growth kinetics of malignant tumors using a two-stage carcinogenesis model. The survival and hazard functions for cancer relapse time are derived, and a simulation study is performed to validate the underlying model. 相似文献
86.
In this article, another version of the generalized exponential geometric distribution different to that of Silva et al. (2010) is proposed. This new three-parameter lifetime distribution with decreasing, increasing, and bathtub failure rate function is created by compounding the generalized exponential distribution of Gupta and Kundu (1999) with a geometric distribution. Some basic distributional properties, moment-generating function, rth moment, and Rényi entropy of the new distribution are studied. The model parameters are estimated by the maximum likelihood method and the asymptotic distribution of estimators is discussed. Finally, an application of the new distribution is illustrated using the two real data sets. 相似文献
87.
Serkan Eryilmaz 《统计学通讯:理论与方法》2013,42(18):3416-3427
In this article, we study the reliability properties of systems under bivariate log-logistic model which comes out from a particular stress-strength analysis. For this model, we obtain basic reliability characteristics of series and parallel systems and investigate their properties. We also derive distribution and moments of cold standby system under the abovementioned exchangeable model. 相似文献
88.
89.
AbstractFor two components and one standby redundancy, we develop a characterization on the hazard rate order and the reversed hazard rate order of the redundant system lifetime in the context of mutually independent components lifetimes. Also, the likelihood ratio order is derived on the lifetime of the series system with two components lifetimes and two matched active redundancies lifetimes both following the proportional hazard model. 相似文献
90.
For the linear-exponential distribution with increasing hazard rate, exact and explicit expressions for means, product moments and percentage points of order statistics are obtained. Some recurrence relations for both single and product moments of order statistics are also derived. These recurrence relations would enable one to obtain all the higher order moments of order statistics for all sample sizes from those of the lower order 相似文献