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根据炉渣结构的共存理论和相图,推导了CaOB2O3和FeOFe2O3B2O3渣系的热力学计算模型。结果表明:(1)理论计算的CaOB2O3渣系的作用浓度NCaO及NB2O3与实测的活度aCaO及aB2O3一致;(2)理论计算的FeOFe2O3B2O3渣系的氧化能力NFetO与实测的炉渣FetO的活度值相符合。这说明本文提出的热力学计算模型是合理的。  相似文献   
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Multi-agent technologies have been widely employed for the development of web-based systems, including web-based e-markets, web-based grid computing, e-governments and service-oriented software systems. In these service-oriented systems, service provider agents and service consumer agents are autonomous and rational entities, which can enter and leave the environments freely. For simplicity, we use terms ‘provider’ and ‘consumer’ to represent this two types of agents. How to select the most suitable service providers according to a service request from a consumer in such an open environment is a very challenging issue. In this paper, we propose an innovative trust model, called the GTrust model, for service group selection in general service-oriented environments. In the GTrust model, the trust evaluation for a service group is based on the functionality coverage of the group, the dependency relationships among individual services in the group, the ratings of individual services on the attributes of the service request and a similarity measurement of the extent to which reference reports can reflect the service request in terms of the priority distribution of attributes. The experimental results and analysis demonstrate the good performance of the GTrust model on the service group selection in service-oriented environments.  相似文献   
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MVB (Multifunction Vehicle Bus), defined in IEC 61375, has been broadly adopted as the communication standard between embedded control systems on-board modern trains. In this work a new method to take advantage of the full bandwidth of the channel using an OFDM technique is described. With this new method it is possible to share the physical medium between standard MVB traffic and new OFDM traffic. A 90 Mbps theoretical bitrate can be achieved. The results of this work have been validated in a test bench including standard MVB nodes transmitting on a line similar to a real vehicle bus.  相似文献   
6.
Physical activity monitoring for youth is an area of increasing scientific and public health interest due to the high prevalence of obesity and downward trend in physical activity. However, accurate assessment of such activity remains a challenging problem because of the complex nature in which certain activities are performed. In this study, we formulated the issue as a machine learning problem—using a diverse set of 19 physical activities commonly performed by youth—via two approaches: activity recognition and intensity estimation. With the aid of training data, we implemented a distance metric learning method called DML-KNN that utilizes time-frequency features and is capable of effectively classifying both continuous and intermittent movement in youth subjects. Four different time-frequency feature extraction methods were then systematically evaluated. Our results show that the DML-KNN method performed competitively, especially when using features extracted by the Tamura method for intensity estimation, and by the Square Coefficient method for activity recognition.  相似文献   
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介绍ADSL传输技术使用情况及与ISDN等的比较。  相似文献   
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Mortar mixes with different water-cement ratios and consistency were impregnated with methyl-methacrylate monomer and polymerized thermally under water using the free radical initiator, -azobis (isobutyronitrile). Results on drying, impregnation and polymerization are presented. It is shown that a considerable amount of polymer remained strongly adhered or chemically inserted in the inorganic matrix. The molecular weight of the inserted polymer is higher than that obtained in the solvent extracted polymer and this is also higher than the polymer molecular weight obtained by bulk polymerization under the same conditions. The compressive and flexural strength of the impregnated mortar were found to be a function of the amount of polymer in the composites. Fracture behaviour under load, and polymer distribution inside the composites were examined by scanning electron microscopic techniques (SEM). It was observed that the polymer acts in two ways, first as a filler of porous and microcrack voids, secondly forming an anisotropic irregular network improving the bond characteristic of the interface between aggregate and matrix. Furthermore, due to the the adhesion of the polymer to both phases, it acts as a reinforcement and improves the mechanical properties, in particular the flexural strength.  相似文献   
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本文主要研究了操作条件的改变对分离效果的影响,在研究中还考察了NaCl和絮凝剂加入乳浊液后对分离过程产生的增效作用。得到了一个与实验数据相关联的数学方程,为估算油的去除率提供了一个有用的工具。在电浮选装置中采用不溶电极,为今后的分离技术提供了一个新思路。  相似文献   
10.
根据科技项目情况统计涉及的统计表类型繁多 ,要求统计数字准确、图表精美的特点 ,设计了一个由2 2个关联的表构成的科技项目统计关系数据库 ,对全省每年的科技项目进行各种统计、绘制统计图表 ,并介绍了VFP与 EXCEL间的通信 ,VFP生成图表等几个实现重点  相似文献   
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