Effectiveness of spatial representation in the formation of network communities: experimental study on community organizer

In this paper, we present and discuss Community Organizer, a system designed to support network communities. The main characteristic of Community Organizer is the use of spatial representations for the relationships among community members including the communications exchanged among these members. These spatial representations reflect the degree of closeness of interests and concerns among the members, and are intended to provide users with clues on how to form network communities. In order to investigate the effectiveness of the proposed spatial representations, we conducted experiments with two different versions of the software. One version offered meaningful spatial representations while the other version did not. The subjects who used the former software version felt a greater sense of ‘community’, enjoyed using the software more, and actively used it longer than the subjects using the latter software version (control condition). These results indicated that the proposed spatial representations are effective in supporting network community formation.     

磷－溴双元素阻燃涤纶切片的研制

分析了磷－溴（Ｐ－Ｂｒ）阻燃剂的特性及阻燃机理。应用Ｐ－Ｂｒ阻燃剂进行了阻燃涤纶切片的开发研制试验，结果表明：Ｐ－Ｂｒ阻燃剂阻燃效果好、能高度分散并有良好的热稳定性，其所制阻燃涤纶切片有良好的可纺性。     

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本文结合实际资料,对内蒙古赤峰热水镇温泉天然气的地球化学特征进行了分析和研究。结果表明:上述天然气由多种成因气体组合而成。其中He属壳源放射性成因,CO_2属有机成因,CH_4属无机合成,N_2属大气成因。     

Measurements of Stress Intensity Factors of an Interface Crack Under Mixed Mode Loading

The optical method of caustics has been utilised to measure both the stress intensity factor for a crack lying along the interface of an aluminium/epoxy bimaterial specimen, and the mode mixity arising from the difference in the elastic properties across the interface. Measurements were carried out by using a novel modification to the method whereby caustics are produced and measured from both sides of the specimen, so compensating automatically for the distortion induced in the specimen due to misaligned loading fixtures. A flat reflective surface across the interface was obtained by adhering a reflective coating to the specimen. Verification that this coating does not affect measurement accuracy was obtained by comparing stress intensity factors measured from coated and uncoated monolithic aluminium specimens where good agreement was found to exist between both measurements.     

Kinetic study of the hydrolysis of isocyanic acid in the gas phase

The hydrolysis of isocyanic acid in the gaseous phase has been investigated at temperatures between 553 and 613 K by mass spectrometry and evaluated to obtain the corresponding kinetic data. The reaction order and reaction constant have been determined. Finally, the influence of water on the catalysed formation of melamine from isocyanic acid under the operating conditions employed has been investigated in order to determine whether there is a need to try the process gas.     

Mechanization techniques for poplar development in Turkey

Annual commercial poplar wood production in Turkey is about 3.6 million cubic meters, half of which comes from hybrid poplar I-214. The poplar plantation areas of Turkey are 70% of the poplar plantation areas of the Near and Middle Eastern countries, and nearly 5% of the world. In this study, unit times of standard operations were investigated in poplar nurseries and plantations in which new mechanical technology was applied and compared with traditional methods. Analyses of unit times were made on 11 treatments for poplar nurseries and nine treatments for poplar plantations; some new methods are also recommended. Mechanization methods based on new technologies give promising results in poplar nurseries and plantations.     

海底沉积物中天然气水合物生成和分解规律研究进展

对国内外有关海底沉积物中天然气水合物生成和分解规律方面的研究进行了详细调研,得到如下结论:天然气水合物的生成和分解条件在海底沉积物中与在井筒、管道中有明显不同,其主要原因是多孔介质中流体与孔隙壁面间的界面效应对海底沉积物中天然气水合物的形成条件会产生明显影响;在海底沉积物中天然气水合物生成和分解条件的数值模拟技术研究方面,研究者大都假设以天然气水合物作为盖层的成藏类型,借助常规油气藏数值模拟技术进行模拟研究;影响海底沉积物中天然气水合物生成和分解条件的因素很多,因此海底沉积物中天然气水合物生成和分解规律研究必须借助试验模拟、数值模拟和现场测试相结合的综合方式进行。该调研成果可为今后天然气水合物经济有效开采技术方案选择和进行天然气水合物危害控制等提供参考。     

Experimental Study of Concrete Subjected to Explosive Loading

The main subject of this paper is to demonstrate the response of structural concrete to different imposed strain rates. Attention is focused on the strain rate about 10^-2 s ^-1>, where some technical difficulties are experienced when an exact determination of mechanical properties for quasi-brittle materials is attempted. The design of a measurement system, which realizes computer acquisition, analysis, and graphic representation of data, is also presented.     

论高校开放式实验教学体系的构建

实施开放式实验教学已成为当前高校实验教学改革的突破口。实施开放式实验教学，必须构建科学的运行体系，主要包括教学目标体系、内容体系、保障体系和效能考评体系四个方面。     

高坝洲电厂机组挖潜增容研究

介绍了高坝洲电厂从减少弃水增加运行调度灵活性出发,挖掘机组潜能,扩大机组容量.对此方案的可行性进行了技术论证和试验.