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61.
主要介绍基于WEB的电子政务系统智能化模块,由电子政务概念引出智能化电子政务系统建设的必要性,具体分析智能化的电子政务系统应具备的模块,最后简单论述了电子政务系统发展趋势。  相似文献   
62.
计算机网络技术的飞速发展,计算机网络的应用也越来越多,促使很多企业也开始扩展网络办公及其他网络业务,那么网络设备的选择与维护便成为他们最关心的问题。  相似文献   
63.
Li KW  Yu RF  Han XL 《Applied ergonomics》2007,38(3):259-265
A study on combined manual materials-handling tasks performed on floors under three friction levels was conducted. Eight male subjects participated in the study. The maximum acceptable weight of handling, including lifting, carrying for 3m, lowering, and walking 3m back at twice per minute was determined. The subject then performed the same tasks for 10 min. Heart rate, Vo2, energy efficiency, perceived sense of slip, and rating of perceived exertion for whole body strain were measured. The results showed that the effects of friction level on the maximum acceptable weights of handling, perceived sense of slip, Vo2, and energy efficiency were statistically significant (p相似文献   
64.
对沈阳市桃仙镇荒山子村一个农户生态经济系统进行分析,结果表明:该农户正处于从传统农业向现代农业的过渡阶段,经济效益较好,整体技术水平和生态效益低,后两了该农户的进一步发展,以目前的生产水平,应采取户与户联合,取得规模效益,以当前农业产业化的发展。  相似文献   
65.
Disruption damage conditions for future large tokamaks like ITER are nearly impossible to simulate on current tokamaks. The electrothermal plasma source SIRENS has been designed, constructed, and operated to produce high density (> 1025/m3), low temperature (1–3 eV) plasma formed by the ablation of the insulator with currents of up to 100 kA (100 s pulse length) and energies up to 15 kJ. The source heat fluence (variable from 0.2 to 7 MJ/m2) is adequate for simulation of the thermal quench phase of plasma disruption in future fusion tokamaks. Different materials have been exposed to the high heat flux in SIRENS, where comparative erosion behavior was obtained. Vapor shield phenomena has been characterized for different materials, and the energy transmission factor through the shielding layer is obtained. The device is also equipped with a magnet capable of producing a parallel magnetic field (up to 16 T) over a 8 msec pulse length. The magnetic field is produced to decrease the turbulent energy transport through the vapor shield, which provides further reduction of surface erosion (magnetic vapor shield effect).  相似文献   
66.
Comments on J. J. Christensen-Szalanski and L. R. Beach's (see record 1984-21471-001) conclusion that the attention given to commentaries and replies to articles did not justify the extra space and argues that citation indexes do not measure the major usefulness of these commentaries. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
纳米SiO2材料的应用   总被引:11,自引:1,他引:11  
本文根据纳米的奇异特性,简要综述纳米SiO2在各个领域中的应用。  相似文献   
68.
溶胶—凝胶法制备有机改性硅酸盐的研究进展   总被引:3,自引:0,他引:3  
综述了有机改性硅酸盐的溶胶-凝胶合成路线,并简要介绍它们的结构、性能及应用  相似文献   
69.
The aboriginal use of reed and bone as raw materials for knives and daggers, respectively, has been well-documented ethnographically in some geographical areas of Melanesia. Because of the significant role that these weapons played in inter- and intra-ethnic aggression, they can potentially have retained smears from the contact with human blood. To carry out a guiding low-vacuum scanning electron microscopy (SEM) study of specific interest to ethnography, the outsides of a fragment of stalk of giant cane (Arundo donax) and tibial diaphysis of domestic sheep (Ovis aries) were smeared with peripheral human blood. No biological specimen preparation was applied to the samples. After just over 1 month, bloodstain boundaries and their neighboring inner areas were examined via secondary electrons by a variable-pressure SEM (VP-SEM) working in low-vacuum mode. On both substrates, bloodstains exhibited micro-scales. No janocyte (erythrocyte negative replica) was observed in the examined areas. However, erythrocytes were seen crowded together as grain-shaped corpuscles in the smear on reed, and several hecatocytes (moon-like shaped erythrocytes) were evidenced in the smear on bone. The results of this study suggest that a VP-SEM working in low-vacuum mode can be used fruitfully to detect blood remains in medium-sized reed and bone antique aboriginal artifacts. This procedure can prospectively help to ethnographic museum curators and aboriginal-art surveyors as an easy guiding test in the valuation of antique traditional weapons prior to acquisition, when the real use of a piece has been claimed by the supplier.  相似文献   
70.
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