查询词典 generating

In this paper, we use approximate distribution comes from probability generating function in estimating credit VaR. Further, we perform the credit VaR sensitive analysis for multi-sector factors based on different sector correlation assumption.

本文在信用风险加成模型之下，利用机率产生函数的近似分配计算信用风险值，并在多个部门因子中，在不同相关性部门因子分配假设下，比较信用风险值之敏感度分析。

By the supplementary variable method the steady state equations and probability generating function for the customer number in the system including one customer in service are obtained. The stability conditions under which the steady state solution exists, the average customer number and the average sojourn time in the system.

通过补充变量法，首先建立了系统稳态下的状态转移方程，用概率母函数的方法求解得到了稳态下系统队长的概率母函数，进而求出系统稳态解存在的稳态条件和稳态下系统的平均队长和顾客在系统中的平均逗留时间。

After studying the MAC protocol of Ad hoc network and by modifying the Wireless Token Ring Protocol, a new uncontested Distributed Parallel Wireless Polling Access Protocol that can provide MAC QoS guarantees for Ad hoc network is presented, and the mathematical model is established by the embedded Markov chain theory and the probability generating function method. Based on it, the mean value of queue length and message waiting time are explicitly obtained.

摘要该文对Ad hoc网络的MAC层协议进行了研究，通过对无线令牌环协议进行改进，提出了一种新的具有QoS保障的无竞争的分布式并行无线轮询访问协议，并采用嵌入Markov链和概率母函数的分析方法，用限定服务规则进行了系统建模，在系统模型的基础上得到了系统的平均排队队长以及平均等待时间的解析结果。

Under the service rule that customers who first come would first get the service, we use the structure analysis method to get the stochastic decomposition of the queue length with the generating function of probability and the steady waiting time with Laplace-stieitjes transforms.

重点分析了带启动期的一般减量服务的单重休假$M/G/1$排队系统的一般结构，利用结构分析的方法，在先来先服务规则下求得稳态队长的随机分解的概率母函数和稳态等待时间的随机分解的$LST$，同时，讨论了系统处于平衡的条件及其概率含义的直观解释，进一步讨论了系统处于休假期、忙期、忙循环等状态时的各项性能指标及系统状态分布。

Aiming at complicated computing and difficulty of being realized when extending single sensor PHD filtering to the multi-sensor case by means of probability generating function, a multi-sensor multi-target sequential particle-PHD tracking algorithm is proposed based on the thought of sequential filtering for a centralized fusion system. The algorithm chooses the importance density function with regard to every sensor, and updates sample particle of every sensor layer by layer.

当采用概率母函数将单传感器PHD滤波推广到多传感器情形时，针对计算繁琐，难于实现的问题，本文基于集中式融合系统的有序滤波思想，提出多传感器、多目标有序粒子PHD跟踪算法，该算法通过选取与各传感器相关的重要性密度函数，层层更新各传感器的采样粒子，达到多传感器多目标有序PHD跟踪。

Secondly, by establishing a discrete time Markov model with spatial reuse for a MANET, we analyze the performance of the network under the AODV routing protocol. The average route length and the probability to communicate within a limited hop distance are obtained. Several performance parameters of the route discovery and route maintain process are analytically studied, such as the probability generating function and the expectation of the flooding distabce. the probability that a route is discovered by a query packet with a "hop limit", the probability that a request packet finds a valid route, the average time needed to discover a valid route and the cost to successfully route a data packet to its destination. Furthermore, we present a concrete example based on the transmitter characteristic of directional antennas and obtain the corresponding results.

建立了移动自组网络空间可重用的离散时间马氏链模型，得到了AODV路由协议下网络任意两节点间的平均路由长度、在指定"跳限"要求下通信的概率；对随选型路由协议下路由发现和路由维护过程中若干网络性能参数进行了解析分析，如网络中任意两节点问的泛洪距离的概率母函数及其期望、限定泛洪步数时成功寻路的概率、发现一条有效路由的平均时间、成功路由的代价等；并基于定向天线的发射特征给出了一个具体实例，分析计算了相应的网络性能参数。

The dissertation includes the work as follows: Firstly, we present a random graph model with spatial reuse for a dense MANET which using directional antennas. The analytic formula of several important performance parameters for the MANET are obtained under the DSR routing protocol, such as the average flooding distance, the probability generating function of the flooding distance, the probability of a flooding route to be symmetrically valid, the average time to find a symmetrically valid route and the cost to successfully route a data packet to its destination. We compare the two models with spatial reuse and without spatial reuse by evaluating these parameters. It is shown that the spatial reuse model is much more effcctive in terms of the performance of the dense network with directional antenna, because the bigger is the degree of spatial reuse, the smaller is the average flooding distance.

在定向天线技术的支持下，建立了移动自组网络空间可重用的贝努利随机图模型，获得了DSR路由协议下平均泛洪距离的解析公式和泛洪距离的概率母函数：给出了有效对称路由概率、发现有效路由平均时间、成功路由代价等关键性能参数的解析分析；在网络性能参数定量分析的基础上，对空间可重用和无重用的网络进行了比较分析，结果显示空间重用度增大，则平均泛洪距离、路由发现时延、网络代价减少。

In the point reactor model, the probability function(n, t0, t) of a source neutron at time t0 leading to n neutrons at time t is dealt with. The non-linear partial differential equation for the probability generating function G(z; t0, t) is derived. By solving the equation, we have obtained an approximate analytic solution for a slightly prompt supercritical sys tem.

在点堆模型基础上，考虑了在t0时刻系统引入一个源中子，在t时刻产生n个中子的概率(n， t0， t)推导了概率生成函数G(z； t0， t)所满足的偏微分方程，并得到了近似解。

We use the approximate distribution comes from probability generating function of CreditRisk+ to value the CDO under the single sector factor and multi-sector factors scenarios. For single sector factor model, we discuss the sensitive analysis of CDO fair spread by different default probability, default correlation and loss given default. For multi-sector factors model, we exam the CDO fair spread based on different sector correlation assumption, such as Gamma distribution in moment match method, multivariate Gamma distribution and compound Gamma distribution.

本文在信用风险加成模型之下，利用机率产生函数的近似分配评价抵押债务债券，并考虑单一部门因子与多个部门因子，单一部门因子中，在不同违约机率、违约相关系数和违约损失率下，探讨抵押债务债券公平价差之敏感度分析；多个部门因子中，在不同相关性部门因子分配假设下，如动差配适法的伽玛分配、多维伽玛分配、复合伽玛分配，探讨抵押债务债券公平价差之方法结果比较。

The probability vector can be viewed as a prototype vector for generating solution vectors that have high evaluations with respect to the available knowledge of the search space. Compared with the general genetic algorithm, PBIL discards the complex and problem-correlation operators, which always affect the algorithm's performance highly.

相对于常规遗传算法，PBIL进化算法抛弃了复杂的且对算法性能影响很大的交叉、变异算子，而引入竞争学习的机制，以概率矢量的方式通过采样来产生下一代群体，然后选出群体中最优个体对概率矢量进行更新，直至最后收敛。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。