Service life planning and performance requirements

Service life planning comprises a model for the determination of a reasonable expected service life for buildings and components, and it establishes a routine for the assessment of design alternatives. A design option is considered reasonable when it meets or exceeds performance requirements over time that have been drawn up specifically for the specific project. Due to this assessment reference, there is a very evident link to the concept of performance-based building. Any stakeholder involved in the value chain or in the design process of the building, as well as regulators and building users, can express performance requirements. Identified requirements, both in relevance and in quality, will vary with the stakeholder and his/her perspective of interest. As building sector manufacturers develop most products with reference to standards rather than with reference to specific requirements, there is no direct link from user requirements to the product design. Instead, the building designer has the responsibility to ensure performance requirements are met by the performance of products integrated into the design. As these design decisions also have to be made at the material and component level, a performance-based building would benefit from an established rationale that enables the communication of performance requirements across the relevant system levels in the relevant design processes. A path for the connection of the established concepts of service life planning and performance-based building is presented. The aim is to identify key elements that need to be developed for the successful linkage of performance-based building with service life planning.     

高层建筑擦窗机的选型与建筑设计要求

论述了擦窗机产品的发展现状与安装的必要性；在擦窗机产品的分类与选型考虑因素的基础上，对目前我国擦窗机的型式及其配置做了比较系统的介绍；最后还简单列举了几种擦窗机的布置方式。对高层建筑在建筑设计时就考虑擦窗机的安装型式，结构设计的承载要求等，提供了较为实用的参考。     

An Efficient Code-Based Voxel-Traversing Algorithm

The paper considers an efficient approach to traversing a uniformly-subdivided space pierced by a line segment. A voxel, as the basic constituent element of the uniformly subdivided space, is restricted to having the form of a cube. The algorithm works in two steps. In the first step, the so-called Bresenham voxels are identified and, by comparing their position codes, their type of connectivity is determined. To achieve the required connectivity between neighbouring voxels, the second step of the algorithm is applied to find the missing voxels. In this way, the algorithm efficiently switches between face-, edge- and vertex-connectivity. Although the algorithm works with oating-point precision, it is extremely computationally efficient, and tests of speed compared with the Müller, Cleary & Wyvill, Amanatides & Woo, and Zemčik algorithms are described.     

拼接式彩色等离子体大屏幕显示驱动电路的研究

针对拼接结构的高分辨率彩色等离子体大屏幕系统的应用，指出了刷新型电路模式的不足之处，提出了一种混合型模式的驱动电路。从彩色模块ＡＣＰＤＰ的结构特性出发，详细讨论了该电路的工作原理，驱动波形以及放电过程。     

房屋基础因地道塌陷的加固处理

本文通过对房屋基础因地道塌陷事故的处理，提出一种结构受力合理、施工便利、经济性好的基础加固新方法，供今后实际工程事故处理时参考。     

用傅里叶变换计算单缝衍射的光强分布

现代光学和通讯理论由于引入了傅里叶变换的方法，使计算光学系统和通讯系统的物像的对应关系简洁、清晰。该文用傅氏变换计算长为２ａ、照度为Ａ的均匀缝光源在观察面上的光强分布为Ｉ（ｘ）＝│Ｅ（ｘ）│＾２＝ＡＡ＾２ａ＾２（ｓｉｎ２πｆａ／２πｆａ）此方法也可运用于矩形孔、圆孔等。     

Two years of operational use of Subpixel Automatic Navigation of AVHRR scheme: accuracy assessment and validation

Automated techniques for satellite imagery navigation and co-location are especially required for environmental monitoring activities intensively using satellite data. In this work are presented the results obtained after 2 years of operational use of the Subpixel Automatic Navigation of AVHRR (SANA) scheme. An automatic method for accuracy assessment of satellite navigation techniques, which permits a preliminary evaluation of their performances, dealing with a large collection of test images is also proposed. The navigation accuracy assessment, performed by using a selection of small islands as reference points, is discussed.Results achieved over more than 400 Advanced Very-High-Resolution Radiometer (AVHRR) scenes confirm that the SANA scheme is a very accurate one (computed mean navigation error is generally about one AVHRR pixel). Furthermore, because of its high processing speed, it can be considered a suitable tool for intensive satellite data processing in multitemporal analyses, especially required for environmental studies as well as for operational monitoring purposes.     

大系统分解协调在库群防洪优化调度中的应用

文章介绍了大系统分解协调理论,建立了串联、并联库群水库防洪优化调度模型.以澧水流域并联系统为例进行了优化调度计算,并以常规调度方案成果进行了分析比较论证.     

BINELOCA 程序与广东岭澳核电站大破口失水事故分析

ＢＩＮＥＬＯＣＡ程序是在吸收国外先进大破口失水事故分析计算机程序的基础上，针对我国现有大破口失水事故分析程序的不足和工程应用方面的问题，采用了一些成熟的、新型的和当今国际公认的瞬态热工水力数学物理模型以及水和蒸汽性质参数计算公式改编而成的大破口失水事故分析程序。通过对广东岭澳核电站大破口失水事故的计算表明，ＢＩＮＥＬＯＣＡ程序计算的结果与法国计算的结果是一致的。     

A method to find all solutions of a system of multivariate polynomial equalities and inequalities in the max algebra

In this paper we show that finding solutions of a system of multivariate polynomial equalities and inequalities in the max algebra is equivalent to solving an Extended Linear Complementarity Problem. This allows us to find all solutions of such a system of multivariate polynomial equalities and inequalities and provides a geometrical insight in the structure of the solution set. We also demonstrate that this enables us to solve many important problems in the max algebra and the max-min-plus algebra such as matrix decompositions, construction of matrices with a given characteristic polynomial, state space transformations and the (minimal) state space realization problem.Research assistant with the N.F.W.O. (Belgian National Fund for Scientific Research).Senior research associate with the N.F.W.O.