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41.
研究了H2S吸收液中酸性杂质对吸收平衡的影响,研究表明,H2S在脱硫液中的溶解量随着活性氨的增加而提高,随杂质含量的增加而减少,对于酸性物较多的吸收液,应相应提高总氨量,以提高脱硫液中的活性氨含量。  相似文献   
42.
从真实性的角度出发,利用Bachman的任务特征框架分析了NETEM阅读理解部分对考生交际语言能力的测试.分析表明,NETEM在输入材料方面有较高的真实性,任务涉及的语言能力的真实性也有很大的提高.但从输入与回答之间的关系看,个别题目未能体现交际语言能力的特点,仍有待改进.  相似文献   
43.
In the post-genomic era, proteomics has achieved significant theoretical and practical advances with the development of high-throughput technologies. Especially the rapid accumulation of protein-protein interactions (PPIs) provides a foundation for constructing protein interaction networks (PINs), which can furnish a new perspective for understanding cellular organizations, processes, and functions at network level. In this paper, we present a comprehensive survey on three main characteristics of PINs: centrality, modularity, and dynamics. 1) Different centrality measures, which are used to calculate the importance of proteins, are summarized based on the structural characteristics of PINs or on the basis of its integrated biological information; 2) Different modularity definitions and various clustering algorithms for predicting protein complexes or identifying functional modules are introduced; 3) The dynamics of proteins, PPIs and sub-networks are discussed, respectively. Finally, the main applications of PINs in the complex diseases are reviewed, and the challenges and future research directions are also discussed.  相似文献   
44.
Considering the randomness or interval character of physical parameters and applied loads of composite pressure vessels (COPV), the COPV reliability-analyzing model is built. And then the computational expressions for the mean value, standard deviation and deviation of fiber stress are deduced by the random factor method. The probabilistic and interval reliability designs on COPV are implemented by utilizing the probabilistic method and interval method combined with the improved particle swarm optimization (PSO) algorithm, respectively. The influence of fluctuation of structure uncertain parameters on COPV design thickness is inspected. Finally, examples are given to demonstrate that both probabilistic and interval reliability methods can satisfy the safety requirement and both are of higher rationality than the traditional safety factor method. And probabilistic method has a lower relative error but a higher computational complexity contrasted with the interval method.  相似文献   
45.
Self-excited vibration problems of maglev vehicle-bridge interaction system   总被引:1,自引:0,他引:1  
The self-excited vibration problems of maglev vehicle-bridge interaction system were addressed, which greatly degrades the stability of the levitation control, decreases the ride comfort, and restricts the cost of the whole system. Firstly, the coupled model containing the quintessential parts was built, and the mechanism of self-excited vibration was explained in terms of energy transmission from levitation system to bridge. Then, the influences of the parameters of the widely used integral-type proportion and derivation(PD) controller and the delay of signals on the stability of the interaction system were analyzed. The result shows that the integral-type PD control is a nonoptimal approach to solve the self-excited vibration completely. Furthermore, the differential-type PD controller can guarantee the passivity of levitation system at full band. However, the differentiation of levitation gap should be filtered by a low-pass filter due to noise of gap differentiation. The analysis indicates that a well tuned low-pass filter can still keep the coupled system stable.  相似文献   
46.
读者决策采购作为一种全新的基于读者需求的资源建设模式,目前国内还没有高校图书馆实施。介绍了读者决策采购面临的问题,提出PDA要在我国高校图书馆成功实施,需制定严格的标准、选择合适书商并及时进行跟踪与评价。  相似文献   
47.
采用外加恒电位下腐蚀电流-温度扫描方法研究了在0.5%Cl^-溶液中,SO4^2-浓度对316不锈钢点腐蚀行为的影响.结果表明,随着SO4^2-浓度的增加,钝化电流增加,开路电位降低.当SO4^2-浓度低于0.42%时,316不锈钢的临界点蚀温度比不存在SO4^2-时的临界点蚀温度低;当SO4^2-浓度大于0.42%时,临界点蚀温度比不存在SO4^2-时的临界点蚀温度高.从离子竞争吸附的角度进行分析,对SO4^2-加速与抑制点蚀两种作用规律的形成原因进行了解释.  相似文献   
48.
49.
EDITORIAL     
The process undertaken by an information seeker, in order to form relevance decisions regarding documents, is defined as “Document Triage.” To better facilitate users’ needs in their triage activities, interactive interfaces have begun to evolve within on-line academic repositories. In order to complement current work on interface design and interaction, and produce custom guidelines to inform the creation of triage interfaces, we examine how interfaces that alter the document presentation and structure affect information seekers’ visual and navigational attention. We present a set of heuristics for both creating and evaluating such interfaces.  相似文献   
50.
The aim of our study was to further develop an understanding of social capital in organizational-knowledge-sharing. We first developed a measurement tool and then a theoretical framework in which three social capital factors (social network, social trust, and shared goals) were combined with the theory of reasoned action; their relationships were then examined using confirmatory factoring analysis. We then surveyed of 190 managers from Hong Kong firms, we confirm that a social network and shared goals significantly contributed to a person's volition to share knowledge, and directly contributed to the perceived social pressure of the organization. The social trust has however showed no direct effect on the attitude and subjective norm of sharing knowledge.  相似文献   
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