It is proved that the right spread order is closed under the formation of parallel systems with independent and identical components. As an application,the simple upper bounds for both the mean and the variance of the...It is proved that the right spread order is closed under the formation of parallel systems with independent and identical components. As an application,the simple upper bounds for both the mean and the variance of the life length of a parallel system with independent and identical NBUE components are obtained. Furthermore,it is proved that the right spread order is also closed under increasing convex transformations under some conditions.展开更多
It is shown that the total life of a parallel system with independent and identical (i.i.d.) exponential components is smaller in the right spread order than an exponential life with the sane mean as the system. As ...It is shown that the total life of a parallel system with independent and identical (i.i.d.) exponential components is smaller in the right spread order than an exponential life with the sane mean as the system. As applications, simple upper bounds for the mean and the variance of the life length of a parallel system with i.i.d. NBUE components are established, as well as the preservation property of the convolution of NBUE and exponential randorn variables.展开更多
Some stochastic comparisons of generalized order statistics under the right spread order, the location independent riskier order and the total time transform order are investigated in this paper. The underlying distri...Some stochastic comparisons of generalized order statistics under the right spread order, the location independent riskier order and the total time transform order are investigated in this paper. The underlying distributions and parameters on which generalized order statistics are based are also surveyed to obtain the conditions for increasing the expectations of spacings between the first two generalized order statistics and between the last two generalized order statistics.展开更多
文摘It is proved that the right spread order is closed under the formation of parallel systems with independent and identical components. As an application,the simple upper bounds for both the mean and the variance of the life length of a parallel system with independent and identical NBUE components are obtained. Furthermore,it is proved that the right spread order is also closed under increasing convex transformations under some conditions.
基金Supported by National Natural Science Foundation of China under Grant No.10201010Action Programming of Lanzhou University.
文摘It is shown that the total life of a parallel system with independent and identical (i.i.d.) exponential components is smaller in the right spread order than an exponential life with the sane mean as the system. As applications, simple upper bounds for the mean and the variance of the life length of a parallel system with i.i.d. NBUE components are established, as well as the preservation property of the convolution of NBUE and exponential randorn variables.
基金Supported by Program for Young Talents in Artillery College.
文摘Some stochastic comparisons of generalized order statistics under the right spread order, the location independent riskier order and the total time transform order are investigated in this paper. The underlying distributions and parameters on which generalized order statistics are based are also surveyed to obtain the conditions for increasing the expectations of spacings between the first two generalized order statistics and between the last two generalized order statistics.
基金Supported by the NNSF of China(Grant No.:10171093)the National 973 Fundamental Research Program on Financial Engineering(Grant No:G1998030418)the Doctoral Program Foundation of Institute of High Education.