基于多变量混合Poisson分布的最优BMS设计

机动车辆保险精算中的奖惩系统（Ｂｏｎｕｓ－ＭａｌｕｓＳｙｓｔｅｍ,ＢＭＳ）的研究主要集中于汽车第三者责任保险的场合,ＪｅａｎＬｅｍａｉｒｅ在［１］中对此作了详细的探讨,本文作者在［２］中讨论了机动车辆车损险的分类最优ＢＭＳ,孟生旺在［３］中讨论了机动...     

Influence of human immunodeficiency virus infection on neurological impairment: an analysis of longitudinal binary data with informative drop-out

A study to investigate the human immunodeficiency virus (HIV) status on the course of neurological impairment, conducted by the HIV Center at Columbia University, followed a cohort of HIV positive and negative gay men for 5 years and assessed the presence or absence of neurological impairment every 6 months. Almost half of the subjects dropped out before the end of the study for reasons that might have been related to the missing neurological data. We propose likelihood-based methods for analysing such binary longitudinal data under informative and non-informative drop-out. A transition model is assumed for the binary response, and several models for the drop-out processes are considered which are functions of the response variable (neurological impairment). The likelihood ratio test is used to compare models with informative and non-informative drop-out mechanisms. Using simulations, we investigate the percentage bias and mean-squared error (MSE) of the parameter estimates in the transition model under various assumptions for the drop-out. We find evidence for informative drop-out in the study, and we illustrate that the bias and MSE for the parameters of the transition model are not directly related to the observed drop-out or missing data rates. The effect of HIV status on the neurological impairment is found to be statistically significant under each of the models considered for the drop-out, although the regression coefficient may be biased in certain cases. The presence and relative magnitude of the bias depend on factors such as the probability of drop-out conditional on the presence of neurological impairment and the prevalence of neurological impairment in the population under study.     

工业经济效益指标体系的再思考

为了适应社会主义市场经济的发展,国家统计局会同财政部、国家经贸委等有关部门对原有我国工业经济效益指标体系进行了修改,制订了一套新的工业经济效益综合评价考核指标体系,包括７项指标：总资产贡献率、资本保值增值率、资产负债率、流动资产周转率、成本费用利润率...     

多源场的高斯定理及其应用

现行的电磁学对线电荷的能量公式、静电平衡条件都没有直接推导过.本文先提出多源场的高斯定理公式,然后进行推导,以供参考.     

网絡协議TCP/IP

网络协议TCP/IP,分别相当于ISO/OSI参考模式中的第四层和第三层,源于美国国防部ARPANET的协议标准.目前,在高档微机工程工作站中得到广泛的应用,并成为工业界的一个“公认”标准. 本文介绍TCP/IP协议,并结合对B-NET(运行于16位微机DUAL系统83和UNIX系统V)中的TCP/IP的提取和分析,着重说明它们的接口及其执行过程机理.     

关于动力学理論中的扰动方法

本文讨论了动力学理论中求解Vlasov-Maxwell方程的扰动方法,证明了第一次线性化后的高阶分布函数对研究电磁波与带电粒子之间的互作用没有影响,并给出了第二次线性化后的Vlasov-Maxwell方程的一般求解方法.     

脊波导回旋管的大信号分析

本文在建立脊波导大回旋半径回旋管模型的基础上,对此回旋管做了非线性理论计算和分析,给出了脊波导场和QP_W公式的表达式。对于脊波导TE_(101)、TE_(301)模式电子回旋基波和回旋三次谐波工作的三种回旋管情形做了详细的计算。结果指出,TE_(301)回旋三次谐波工作的回旋管有51％的高效率。     

成电8010分布式計算机之特点

成电8010是基于单板机开发成功的分布式微机过程控制系统。该系统的性能特点是任务的动态调度、机间合作、优美降级和资源分享等。这些特点使其应用非常成功。本文就是对这些性能特点作相应的分析和介绍。     

黄化型大麦的系列研究 Ⅲ南黄大麦生长发育的调查

本文系统地报道了南黄大麦与原品种早熟3号在生育期、植株高度、叶片长宽、分蘖数以及穗部性状等方面的比较.指出南黄大麦除出土时间,倒二叶的长宽与早熟3号基本一致,剑叶长宽略大于早熟3号外,其余性状差异显著.植株矮小,生长发育缓慢,这与黄化型大麦叶色浅,叶绿体的片层结构不发达,光合机能弱,光合产物少有关.     

Convective Filmwise Condensation of R-11 inside a Vertical Tube

Partial condensation of refrigerant R-11 was experimentally and theoretically studied. The test apparatus consisted of two concentric tubes, with the vapor flowing downward in the inner tube and the cooling water in the annular space in countercurrent direction. By using the available dimensionless correlation, the mean heat transfer coefficient of the cooling water was determined, and then the mean condensationheat transfer coefficient was calculated from the overall heat transfer coefficient.The model of a homogeneous two-phase mixture of liquid and vapor, and Prandtl's principle of analogy between the momentum and heat transfer were used to establish the type of the correlation. Adopting the methods of the gradually linear regression and F-level evidence testing, the present paper proposed the dimensionless correlation to predict the relationship among the mean Nusselt number, Prandtl number, Kutateladze number and the dimensionless tube length.