Work-oriented development of knowledge-based systems: a case for multiple perspectives

System development is strongly influenced by the perspectives used by system developers. Current development methods for knowledge-based systems are based on an information processing perspectives of experts and users which has been criticized by a number of researchers. The paper argues that work-oriented development of knowledge-based systems requires the parallel use of multiple perspectives (including the information processing perspective), and that the use of any single perspective is potentially dangerous. As an example of the importance of using multiple perspectives, thepaper presents the situated action perspective, and shows how it complements the information processing perspective.     

浅谈做好螺丝湾水电站施工质量,工期,投资控制的几项措施

螺丝湾水电站作为云南省电力局（ 集团公司） 、迪庆州、省投资公司三方合资建设的电站，是迪庆藏族自治州自建国以来投资最大的一个建设项目，它的建成，开创了滇西北水电资源多方合资开发的先例，有其特殊的经济和政治意义。本文结合螺丝湾水电站建设的实际情况，论述了在市场经济条件下做好螺丝湾电站建设中“三控制”的几项措施     

含氮化合物废气选择性催化氧化技术研究进展

通过对当前含氮化合物废气治理技术的对比分析,总结选择性催化氧化的相关技术优势。根据对含氮化合物的种类及来源分析,介绍氨气、腈类、胺类及其他含氮化合物的催化净化技术。重点总结催化剂的种类、研发进展和在实际使用中可能遇到的问题,同时展望含氮化合物废气选择性催化氧化技术的研发方向。     

Simulation of toxic gases and vapours removal by activated carbon filters

The system ASC carbon filter/cyanogen chloride was studied by simulation. Three filter configurations and several models, taking into account Langmuir adsorption and second-order reaction between the adsorbed toxic vapour and the active metal on the surface, were developed.The effects of axial dispersion, number of reaction units, film mass transfer units and intraparticle mass transfer resistance on the breakthrough time were studied.Simulation results show that a complex model should be used in order to predict with reasonable accuracy the protection imparted by these filters.     

钒钛磁铁精矿的烧结特性及强化措施

阐述了钒钛磁铁精矿的矿石特点，烧结特性及其与烧结矿质量之间的关系，并提出了强化烧结的措施。     

State multiplicity in CSTR-separator-recycle polymerisation systems

This article continues earlier work (Comput. Chem. Eng. 24 (2000) 209) concerning the design and control of isothermal reactor-separator-recycle systems. The multiplicity behaviour of six reaction systems of increasing complexity, from one-reactant, first-order reaction to chain-growth polymerisation, is investigated. Below a critical value of the plant Damkohler number, Da<Da^cr, the only steady state involves infinite flow rates. Feasible steady states become possible if the critical value is exceeded, Da>Da^cr. For one-reaction systems, one stable steady state is born at a transcritical bifurcation. For consecutive-reaction systems, including polymerisation, a fold bifurcation can lead to two feasible steady states. Moreover, the transcritical bifurcation is destroyed when two reactants are involved. If the gel-effect is included, a maximum of four steady states are possible. When multiple steady states exist, the achievable conversion is constrained by the instability of the low-conversion branch. This has practical importance for polymerisation systems when the radicals’ quasi-steady state assumption is not valid or the gel effect is significant.     

Automated model generation for performance engineering of building automation networks

Large technical systems need to be designed both reliable and efficient. Specialized design tools offer therefore a simplified, abstract design and extend details autonomously in the background. Analytic and simulation based models could improve the quality by testing and dimensioning the design before implementation, but setting up the necessary models is time-consuming and expensive. Therefore many developers ask for analysis tools which are able to create their models from the available information in the design tools. This paper presents such an automated modeling approach basing on an existing design database at the example of a network analysis for building automation fieldbuses. The process of automated modeling is unfolded, and the potentials and limitations are discussed.     

火电机组运行优化系统的现状与展望

简单回顾了国内外在火电机组运行优化领域的研究历程，列举了目前国内外市场上针对火电机组的各种主流运行优化产品的功能特点和应用情况，分析了国外引进产品和国内自主研发产品在中国当前市场环境下各自的优势和劣势。介绍了当前运行优化系统在国内电站机组的应用现状，阐述了国内外运行优化系统在实际应用中存在的问题，并提出了相应的改进意见。对机组运行优化系统的未来发展进行了展望，指出机组运行优化系统将利用先进技术设备和信息平台，与电站管理紧密结合，在日益规范的市场中不断发展完善，为提高电站经济性发挥更大的作用。