外墙保温技术在住宅建筑中的应用

从节约能源、保护环境、改善建筑功能与质量为目的出发，采用外墙保温技术，加强围护结构的保温性，实现建筑节能65％的要求。     

基于专家系统法的异形件最小包络矩形求解

异形件布局问题广泛存在于社会各领域.目前,直接处理异形件布局问题的算法设计难度和计算量较大,而矩形件布局已有一些成熟算法.因此,将异形件转化为矩形件后处理布局能简化问题,并保证良好布局效果.本文基于专家系统法处理异形件,使其转换为易解决布局的包络矩形.     

隔爆型电气设备平面隔爆面传爆原因与预防

分析了平面隔爆面传爆的一些原因并提出了相应的预防措施，通过这些措施。满足了隔爆要求，达到了防爆的目的。     

A two-stage design of adaptive fuzzy controllers for time-delay systems with unknown models

In this article, a systematic two-stage design method for adaptive fuzzy controllers is presented. The proposed control scheme has low computational complexity. Moreover, the exact mathematical model of the plant to be controlled is not required. The fuzzy controller under consideration is based on the proportional-derivative fuzzy control scheme and triangular membership functions. In the design procedure, the domain intervals of the input and output variables are selected with a heuristic approach to minimize a cost function under the constraint of tolerable overshoots in the response curve. A learning scheme is then proposed to automatically adjust the parameters in the fuzzy controller to reduce the error of the system. It can also be used adaptively to improve the system performance of a time-varying system. Simulations and comparisons are included to demonstrate the effectiveness of the proposed method.     

Heat transfer inside a horizontal channel with an open trapezoidal enclosure subjected to a heat source of different lengths

The heat transfer phenomena inside a horizontal channel with an open trapezoidal enclosure subjected to a heat source of different lengths was investigated numerically in the present work. The heat source is considered as a local heating element of varying length, which is embedded at the bottom wall of the enclosure and maintained at a constant temperature. The air flow enters the channel horizontally at a constant cold temperature and a fixed velocity. The other walls of the enclosure and the channel are kept thermally insulated. The flow is assumed laminar, incompressible, and two‐dimensional, whereas the fluid is considered Newtonian. The results are presented in the form of the contours of velocity, isotherms, and Nusselt numbers profiles for various values of the dimensionless heat source lengths (0.16 ≤ ε ≤ 1). while, both Prandtl and Reynolds numbers are kept constant at (Pr = 0.71) and (Re = 100), respectively. The results indicated that the distribution of the isotherms depends significantly on the length of the heat source. Also, it was noted that both the local and the average Nusselt numbers increase as the local heat source length increases. Moreover, the maximum temperature is located near the heat source location.     

基于解析法的复杂封闭空间有源结构声控制

给出了任意凸多面体声腔在内部点源和外力激励下,腔内声压分布的解析解。该解析方法较传统的数值方法,不仅数据准备量小、速度快精度高,且能够解决目前常用的声弹性法难以解决的复杂几何形状的封闭空腔的声固耦合问题。在此基础上,结合有源结构声控制方法,建立了复杂封闭空间局部区域有源消声的模型,给出了矩阵形式的数值算法,并对一类似车辆驾驶室的复杂封闭空腔进行了有源降噪仿真分析,降噪效果良好,证明该方法可以作为复杂封闭空间有源力消声控制系统的建模基础。     

On rationally supported surfaces

We analyze the class of surfaces which are equipped with rational support functions. Any rational support function can be decomposed into a symmetric (even) and an antisymmetric (odd) part. We analyze certain geometric properties of surfaces with odd and even rational support functions. In particular it is shown that odd rational support functions correspond to those rational surfaces which can be equipped with a linear field of normal vectors, which were discussed by Sampoli et al. (Sampoli, M.L., Peternell, M., Jüttler, B., 2006. Rational surfaces with linear normals and their convolutions with rational surfaces. Comput. Aided Geom. Design 23, 179–192). As shown recently, this class of surfaces includes non-developable quadratic triangular Bézier surface patches (Lávička, M., Bastl, B., 2007. Rational hypersurfaces with rational convolutions. Comput. Aided Geom. Design 24, 410–426; Peternell, M., Odehnal, B., 2008. Convolution surfaces of quadratic triangular Bézier surfaces. Comput. Aided Geom. Design 25, 116–129).     

钢支撑支锚刚度对基坑围护结构的影响研究

为研究钢支撑支锚刚度对基坑围护结构的影响,文章以福州地铁潘墩站深基坑工程为背景,运用控制变量法,通过理正深基坑计算软件对不同钢支撑支锚刚度工况下深基坑进行计算分析,得出不同钢支撑支锚刚度下支护结构最大侧向位移、内力、基坑周边地表沉降及支撑轴力变化规律。研究结果表明:钢管内支撑刚度从200MN/m 2增加到600MN/m 2,钻孔灌注桩侧移量减小,地表沉降量降低,钻孔灌注桩迎土侧弯矩、背土侧弯矩呈减小趋势,钢支撑轴力增大,钢支撑对背土侧地下钻孔灌注桩的约束大于迎土侧。适当增加内支撑刚度可控制周边土体变形。     

触发器型压力传感器的研究

本文报道了一种触发器型压力传感器，对这类传感器的电路结构和工作原理进行了理论分析。详细讨论了影响传感器特性的四种因素。定量地分析了调控三角波电压对传感器测量灵敏度和线性范围的影响。对实验结果进行了讨论，理论分析与实验结果基本一致。