遗传算法应用于并联管道计算中的研究

传统求解并联管路的水力计算的方法不是精度低就是限制条件多。设计了一种改进的遗传算法求解的方案，对适应度函数的选取作了详尽地分析，并提出了可增强局部搜索能力的微调变异算子。并联管路的水力计算实例证明了改进的遗传算法的有效性。     

行波管“冷参数”测试技术的研究

针对因螺旋线行波管慢波线的结构特殊,导致其管内输能机构和切断衰减器的反射系数不易测量的问题,提出了利用多点法对输能机构和切断衰减器的反射系数进行测量的方法,并讨论了测试中所用探针反射系数的测试技术。该方法具有无损伤、测试方便等优点,也可用于其他类似特殊结构反射系数的测量。     

Influence of Distributional Shape of Substance Parameters on Exposure Model Output

Uncertainty of environmental concentrations is calculated with the regional multimedia exposure model of EUSES 1.0 by considering probability input distributions for aqueous solubility, vapor pressure, and octanol-water partition coefficient, K(ow). Only reliable experimentally determined data are selected from available literature for eight reference chemicals representing a wide substance property spectrum. Monte Carlo simulations are performed with uniform, triangular, and log-normal input distributions to assess the influence of the choice of input distribution type on the predicted concentration distributions. The impact of input distribution shapes on output variance exceeds the effect on the output mean by one order of magnitude. Both are affected by influence and uncertainty (i.e., variance) of the input variable as well. Distributional shape has no influence when the sensitivity function of the respective parameter is perfectly linear. For nonlinear relationships, overlap of probability mass of input distribution with influential ranges of the parameter space is important. Differences in computed output distribution are greatest when input distributions differ in the most influential parameter range.     

Ivomec—F驱杀牦牛寄生虫后血液生理生化值的测定

Ivomec—F(含1％Ivermectin和1％Clorsulon,以下简称F药)是一种防治家畜体外寄生虫的广谱驱虫药,用该药驱杀牦牛主要寄生虫后,测定其血液生理生化值。结果,F药按1mL/50kgBW皮下注射患主要寄生虫的牦牛后,试验组牦牛RBC、WBC、Hb、BPC等生理指标与对照组相似,TTT、ZnTT、SGPT、Il、TP、A、G、SGOT、ACP、ALP、BUN、BS等生化指标与对照组比较差异不显著(P>0.05),该药对牦牛肝功、肾功、骨骼、心脏、蛋白质和糖代谢等均无任何影响,说明F药按1 mL/50kgBW的剂量驱杀寄生虫对牦牛的血液生理生化值无显著影响。     

Modifying a central composite design to model the process mean and variance when there are hard-to-change factors

Summary.  An important question within industrial statistics is how to find operating conditions that achieve some goal for the mean of a characteristic of interest while simultaneously minimizing the characteristic's process variance. Often, people refer to this kind of situation as the robust parameter design problem. The robust parameter design literature is rich with ways to create separate models for the mean and variance from this type of experiment. Many times time and/or cost constraints force certain factors of interest to be much more difficult to change than others. An appropriate approach to such an experiment restricts the randomization, which leads to a split-plot structure. The paper modifies the central composite design to allow the estimation of separate models for the characteristic's mean and variances under a split-plot structure. The paper goes on to discuss an appropriate analysis of the experimental results. It illustrates the methodology with an industrial experiment involving a chemical vapour deposition process for the manufacture of silicon wafers. The methodology was used to achieve a silicon layer thickness value of 485 Å while minimizing the process variation.     

酒精蒸馏工序重要工艺参数的控制

影响蒸馏塔运行的因素较多,各变量之间相互关联,交叉藕合,工艺参数最为复杂,要使蒸馏过程物料进出平衡,热量平衡,以及各控制点压力、温度、提取成品酒稳定,选择正确的控制方案,解决合理的变量配对至关重要。标志塔正常运行的主要工艺参数是蒸汽包压力。粗塔顶温、精塔中温、冷凝器酒气温度、塔底液位。     

由桥梁动力响应识别过桥汽车参数的灵敏度方法

为了识别通过桥梁汽车的参数，提出了在灵敏度分析的基础上由简支梁桥动力响应识别过桥汽车参数的方法。将汽车抽象为两自由度五参数模型，用有限元方法计算桥梁的动力响应。从对未知参数的猜测值开始，由测试或模拟计算的动力响应用最小二乘法和规则化技巧识别过桥汽车参数，用邻近两次识别参数的百分相对误差（RPE）控制迭代过程的终止。由数值模拟结果可知，识别得到的汽车参数是令人满意的，其中质量的识别精度最高，表明该方法识别过桥汽车参数可行。     

普遍语法与语言习得--从认知的角度看Chomsky的内在主义语言观

建立在对大脑内部语言机制认知基础上的Chomsky内在主义语言观, 完全不同于行为主义的外在主义语言观, 它解释了普遍语法与语言习得的关系, 表明大脑内部语言机制在习得语言中所起到的关键作用.Chomsky的原则--参数理论解释了儿童语言习得的现象,并以此证明儿童掌握的语言不完全是从他们听到的语言中学来的,而是由来自儿童大脑内部的生物属性决定的.     

Maximum likelihood estimation for the proportional hazards model with partly interval-censored data

Summary. The maximum likelihood estimator (MLE) for the proportional hazards model with partly interval-censored data is studied. Under appropriate regularity conditions, the MLEs of the regression parameter and the cumulative hazard function are shown to be consistent and asymptotically normal. Two methods to estimate the variance–covariance matrix of the MLE of the regression parameter are considered, based on a generalized missing information principle and on a generalized profile information procedure. Simulation studies show that both methods work well in terms of the bias and variance for samples of moderate size. An example illustrates the methods.     

平方反比有心力场中三守恒量与轨道几何参数的关系

在平方反比有心力场中运动的质点 ,其角动量、机械能及Runge -Lenz矢量守恒 .本文利用轨道特殊点的几何特性 ,十分简捷地得到了三守恒量与轨道几何参数的关系 .