Dynamics of Vibroprotective Systems with Roller Dampers of Low-Frequency Vibrations

We study low-frequency vibrations of a vibroprotective system of solid bodies formed by a roller damper and a moving load-carrying body under the action of external harmonic excitations. The dynamic equations of combined motion of the working body of the damper over the hinged roller without sliding and the load-carrying body are deduced and numerically analyzed. A new procedure is proposed for the evaluation of the optimal parameters of adjustment of roller dampers in nonlinear systems.     

The effect of aluminium coating on elemental standards in X-ray microanalysis

The standardisation of frozen hydrated bulk biological specimens using gelatin standards is described. The relationship between corrected elemental X-ray counts and ionic concentration was found to be linear, and minimum detectable limits for each element are stated. Variations in uncorrected standard curves were found to be due to changes in aluminium coating thickness. There was an inverse relationship between coating thickness and elemental X-ray counts. The factors causing this are discussed. To avoid errors arising from inconsistent aluminium thickness, experimental material should only be compared with standards of similar aluminium net counts. This can be achieved most easily by mounting and analysing specimen and standard together.     

烧结富氧点火自动控制的实现与应用

介绍了长钢烧结厂在24m^2烧结机上采用富氧点火自动控制的实现与应用。     

预测油气田产量的β模型

通过对油气田产量变化规律进行系统研究，推导建立了预测油气田产量的β模型。该模型不但可以预测油气田产量、累积产量随生产时间的变化，而且可以预测可采储量、最高年产量及其发生的时间。实例检验该模型是可信的。     

一类动态大系统的协调控制模型

讨论了一类离散动态大系统的协调控制问题，提出了相应的模型辨识方法及自适应协调控制算法。通过仿真实例，说明效果是良好的。     

Locally Weighted Learning

This paper surveys locally weighted learning, a form of lazy learning and memory-based learning, and focuses on locally weighted linear regression. The survey discusses distance functions, smoothing parameters, weighting functions, local model structures, regularization of the estimates and bias, assessing predictions, handling noisy data and outliers, improving the quality of predictions by tuning fit parameters, interference between old and new data, implementing locally weighted learning efficiently, and applications of locally weighted learning. A companion paper surveys how locally weighted learning can be used in robot learning and control.     

节理岩体参数对围岩破损区影响的敏感性分析

本文针对黄河拉西瓦地下水电站工程，对节理岩体诸参数对围岩破损区范围的影响进行了敏感性分析。指出了主要敏感参数，对这些参数影响围岩破损区的趋势和可能程度进行了讨论，并对勘察和施工提出了一些意见。     

搅拌工艺对半固态Y112铝合金组织及性能的影响

采用自行研制的机械搅拌装置,研究了不同工艺参数对半固态Y112铝合金组织及性能的影响.研究表明,搅拌温度越高,搅拌速度越大,固相颗粒越细小、均匀和圆整,其抗拉强度与伸长率越高;但温度太高,固相颗粒会熔化,抗拉强度及伸长率也降低;随搅拌时间的延长,固相颗粒先变得细小、均匀和圆整,然后长大,抗拉强度、伸长率先升高后降低.     

Numerical study on PEMFC’s geometrical parameters under different humidifying conditions

Steady-state and three-dimensional simulations were carried out to study the influences of geometrical parameters on the performance of PEMFC under different hydrating conditions. Flow fields, species transport, transport of water in polymer membrane and movement of liquid water in cathode and anode porous layers were determined, in order to accomplish a complete estimation of ohmic and concentration losses of PEMFC power. The geometrical parameters were thickness of the polymer membrane, cathode catalyst layer as well as gas channel to rib width ratio. Every simulation was made under different relative humidities of inlet flows (50 and 100%) for every change of characteristic length. Results show that the influence of the geometrical parameters on ohmic and concentration losses is of considerable importance. The performance of PEMFC is seriously affected under dehydrating conditions. However, such performance may be considerably improved by using suitable geometrical parameters. Cathode and anode liquid saturation may not only affect the transport of species, but also the polymer electrolyte water content. These results show the importance of simultaneously calculating both the water absorption and desorption through the polymer electrolyte and the liquid saturation in the cathode and anode porous mediums to obtain an actual view of ohmic and concentration losses of the PEMFC performance.     

水轮机调速器现代调节技术及选型

对目前比较先进的微机调速器的两种系统结构进行了分析，并对微机调节的控制策略和调节参数的设置及系统配置等作了介绍，并提出了对凋速器技术性能的评价标准和调速器选型时的突出问题，可为实际应用提供参考。