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21.
22.
就5500m^3/min高炉鼓风机动,静叶片损坏事故发生的经过以及有关资料,从几个方面详细分析了事故发生的原因。 相似文献
23.
本文阐述了施工企业内部编制定额的必要性和成本分析平台的实用性,并根据多年的工作经验就建筑施工企业对施工成本的控制谈谈一自己的认识和看法. 相似文献
24.
碘量法测铜中物质性质和分析操作 总被引:3,自引:0,他引:3
本文讨论了碘量法测定铜量中一些有关物质的特性,以及这些性质对分析条件和操作的要求。 相似文献
25.
S. A. Halsey 《Journal of the Institute of Brewing》1985,91(5):306-312
Both transmission and transflectance near infrared spectroscopy have been evaluated for the rapid analysis of beer components. Results of sufficient accuracy have been obtained for ethanol content and Original Gravity. Application of a first derivative mathematical treatment on the spectral data improved calibration equations. Better accuracy was achieved using the transmission mode compared to that using the transflectance mode. 相似文献
26.
随着深亚微米集成电路技术的发展,集成电路的规模越来越大,工作频率越来越高,并正朝着系统集成的方向发展,因而在模拟速度,模拟精度和可模拟的电路规模等各个方面对电路仿真技术提出了新的要求。近年来,各种新的电路仿真方法和仿真系统用相继脱颖百出,并将取代那些传统的,已经无法适应深亚微米技术发展的电路仿真器。 相似文献
27.
R. E. Uhrig 《Progress in Nuclear Energy》1995,29(3-4):357-370
The integrated use of neural network and noise analysis technologies offers advantages not available by the use of either technology alone. The application of neural network technology to noise analysis offers an opportunity to expand the scope of problems where noise analysis is useful and unique ways in which the integration of these technologies can be used productively. The two-sensor technique, in which the responses of two sensors to an unknown driving source are related, is used to demonstration such integration. The relationship between power spectral densities (PSDs) of accelerometer signals is derived theoretically using noise analysis to demonstrate its uniqueness. This relationship is modeled from experimental data using a neural network when the system is working properly, and the actual PSD of one sensor is compared with the PSD of that sensor predicted by the neural network using the PSD of the other sensor as an input. A significant deviation between the actual and predicted PSDs indicate that system is changing (i.e., failing). Experiments carried out on check valves and bearings illustrate the usefulness of the methodology developed. 相似文献
28.
Jeong-Woo Choi Jun Hyo Park Shin Chul Lee Dong-Il Kim Won Hong Lee 《Korean Journal of Chemical Engineering》1995,12(5):528-534
The on-line sensing of viable cell weight in plant cell culture process is applied to analysis and control of process. The
fiber-optic fluorescence sensor was constructed to measure the NADH-dependent fluorescence inNicotiana tabacum plant cell culture and the analysis of fluorescence signal was done to be correlated with the viable cell weight. The structured
kinetic model for cell growth was proposed to estimate the theoretical viable cell weight. The dimensional analysis was proposed
for the interpretation of fluorescence signal, in which the path length, the inner filter effect and the hydrodynamic conditions
were considered as the key factors on fluorescence signal. The dimensional analysis and empirical correlation of fluorescence
signal to viable cell weight was applied to the interpretation of the detected fluorescence signal during cultivation. The
proposed interpretation of fluorescence signal using dimensional analysis was well correlated with the viable cell weight
estimated by the structured kinetic model as well as by empirical correlation. 相似文献
29.
Semantic Web Mining: State of the art and future directions 总被引:2,自引:0,他引:2
Semantic Web Mining aims at combining the two fast-developing research areas Semantic Web and Web Mining. This survey analyzes the convergence of trends from both areas: More and more researchers are working on improving the results of Web Mining by exploiting semantic structures in the Web, and they make use of Web Mining techniques for building the Semantic Web. Last but not least, these techniques can be used for mining the Semantic Web itself.The Semantic Web is the second-generation WWW, enriched by machine-processable information which supports the user in his tasks. Given the enormous size even of today’s Web, it is impossible to manually enrich all of these resources. Therefore, automated schemes for learning the relevant information are increasingly being used. Web Mining aims at discovering insights about the meaning of Web resources and their usage. Given the primarily syntactical nature of the data being mined, the discovery of meaning is impossible based on these data only. Therefore, formalizations of the semantics of Web sites and navigation behavior are becoming more and more common. Furthermore, mining the Semantic Web itself is another upcoming application. We argue that the two areas Web Mining and Semantic Web need each other to fulfill their goals, but that the full potential of this convergence is not yet realized. This paper gives an overview of where the two areas meet today, and sketches ways of how a closer integration could be profitable. 相似文献
30.
介绍了食用盐新国标制定的指导思想,新标准的特点及所修订的内容,指出为做好食用盐的质量检测要掌握和控制的技术要点,以保证和提高盐质分析结果的准确度,确保食用盐产品质量符合标准要求。 相似文献