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901.
随着知识经济的来临,智力资本已成为企业最重要的资本。面临经济形势的巨大变化。企业必须重新思考经营战略,再造核心能力,尽快实现由传统管理方式向现代管理方式的转变。人力资源是企业的第一资源,现代管理必须注重发挥“人”的作用,围绕“人”来构筑企业的核心能力。如今企业员工培训已突破其原本的纯教育意义。而成为现代企业管理的重要方式和手段以及企业竞争力的重要组成部份。对照我区上市公司的实际,培训工作的开展还很不够。企业培训的作用远远没有到位。因此对企业培训的性质、作用、意义和方法必须予以重新认识。 相似文献
902.
用复变函数研究了含椭圆孔的压电材料反平面问题的基本解和裂纹尖端的场强度因子.结果表明:应力强度因子与普通材料的应力强度因子相同,而电位移强度因子与前者有相同的表达形式. 相似文献
903.
Nonlinear analysis of the alcoholic''s EEG 总被引:1,自引:0,他引:1
The nonlinear analysis is used to study the EEGs of the alcoholic and the control. Three kinds of expansions are discussed in order to get a more proper delay and then Liangyue Cao algorithm is implemented efficiently. Totally, there are 40 subjects involved in this study and the average values and the sample variances of D2s are computed. The results show that the average value of D2s of the alcoholic is larger than that of the control when the same electrode was used, which means that the brain dynamics of the alcoholic is more complex than that of the control. On the other hand, for most of the electrodes, the sample variance of D2s of the alcoholic is larger than that of the control, suggesting that the brain dynamics of the alcoholic is less steady. 相似文献
904.
候晓梅 《阜阳师范学院学报(自然科学版)》2002,19(2):73-74
本文从探索教学方法,激发中师学生的学习兴趣出发,谈谈悬念在中师化学教学中的应用。 相似文献
905.
Identifying melts of thickened lower continental crust from high Sr/Y rocks is very important to trace deep crustal processes. Recent studies on Dabie Early Cretaceous granitoids have revealed that melts derived from thickened lower continental crust have higher Sr/CaO ratios and define a high Sr evolution trend compared with normal granitoids. Fractional crystallization of plagioclase can significantly change Sr and CaO contents of melts, but its role in controlling the Sr/CaO ratios of the melts is still unclear. This study gives a direct comparison of plagioclase compositions between normal granitoids and low-Mg adakitic rocks. On the basis of Sr-Ca exchange partition coefficient, discussions on effect of plagioclase crystallization on Sr/CaO ratios of melts show that fractional crystallization of abundant plagioclase cannot significantly change Sr/CaO ratios of granitic melts, which are inherited from their individual initial melts. High Sr/CaO ratios indicate the absence of plagioclase in sources of granitic melts. Therefore, high Sr/CaO correlation can be an important indicator to identify melts derived from thickened lower continental crust. 相似文献
906.
A new implementation of image-processing engine for 3D visualization and stereo video stream display
This paper presents a new implementation of a high-definition image-processing engine, which mainly tar- gets the 3-dimensional (3D) visualization and stereo video stream display of binocular display equipment. The engine is compatible with the mainstream analog and digital stereo videos in component format and is able to receive stereo composite video broadcast signals using an integrated analog stereo video decoder. The four modules include a spatio- temporal scaling transform engine, a 2D-3D converter, an image animating engine, and a 2D scalar operating in pipe- line architecture to implement the video format conversion and the stereo effect enhancement. Furthermore, the data access, hardware structure, and system-level configurations are optimized. Finally, the proposed architecture is realized by 0.18 pm CMOS technology. The application-specific integrated circuit verification results show that the engine can generate a strong feeling of 3D immersion and high- definition image quality with minimal flicker. The chip has wide compatibility and an uppermost 1080P-processing capacity, which has approximately 3.5 million gates with about 43 mm2 die size. 相似文献
907.
Classification of Tibetan lakes based on variations in seasonal lake water temperature 总被引:2,自引:0,他引:2
Widespread lakes on the Tibetan Plateau (TP) are valuable archives for investigating climate and environment changes, which could provide essential information on the mechanisms of past climate changes on the TP and their interaction with the global climate systems. However, there is a lack of in-depth investigation of modern limnological processes in the Tibetan lakes, which hampers the understanding of paleolimnological records and lake ecosystem succession. In this study, we performed continuous temperature monitoring at two lakes, Bangong Co, a freshwater lake in the western TP, and Dagze Co, a brackish lake in the central TP, in order to characterize the patterns of seasonal temperature variability, stratification, and mixing. Temperature data for an entire hydrological year demonstrate that Bangong Co is a dimictic lake and that Dagze Co is a meromictic lake. The higher salinity in the deep water at Dagze Co prevents the lake from overturning completely, and this finding is supported by simulations using a physical limnological model Lake Analyzer. Continuous lake water temperature monitoring provides fundamental data for classifying Tibetan lakes, as well as the hydrological basis for understanding their pa- leolimnological records and ecosystem succession. 相似文献
908.
Haixia Long Bing Liu Bing Hou Chao Wang Keith M. Kendrick Chunshui Yu Tianzi Jiang 《科学通报(英文版)》2014,59(13):1355-1361
The serotonin-transporter-linked polymorphic region (5-HTTLPR) is associated with mood disorders. This association is thought to be due to amygdala hyper- responsiveness to negative emotional stimuli as a result of reduced frontal cortical control. In Caucasians, the short form is associated with this effect, but in Han Chinese we recently found that the long form is involved. Serotonin receptors have rich expression in default mode network (DMN) regions and the recent studies have found an association between the short form of the 5-HTTLPR and DMN functional connectivity (FC) in Caucasians. The present study has investigated whether there may also be an ethnic difference in this influence of 5-HTTLPR on the DMN. We recruited 233 young Han Chinese subjects and calculated the resting-state default-network FC. Our study found that the L carriers had decreased FC in the bilateral medial prefrontal cortex, right parahippocampal gyrus, left middle temporal gyrus, and increased FC in left precuneus (Pcu) compared to SS. The PCC-Pcu FC in L carriers was significantly negatively correlated with the depression scores. Our findings, therefore, suggest that there is also a difference between Caucasian and Han Chinese subjects in the association between the different forms of the 5-HTTLPR and DMN functional connectivity. 相似文献
909.
910.
Preliminary evidence indicating Dome A (Antarctica) satisfying preconditions for drilling the oldest ice core 总被引:4,自引:0,他引:4
Ian ALLISON 《科学通报(英文版)》2008,53(1):102-106
Lowest temperature and snow accumulation rate are preconditions for retrieving the oldest ice core from the polar ice sheets. The 10-m depth firn temperature at Dome A, the summit of the Antarctic Ice Sheet, recorded by an automatic weather station (AWS) was -58.3℃ in 2005 and -58.2℃ in 2006, respectively. The 10-m firn temperature is an approximation of the annual mean air temperature (AMAT), and this is the lowest AMAT that has been recorded on the surface of the Earth. The stable isotopic ratios (δ^18O and δD) of surface snow at Dome A are also lower than at other ice sheet domes along the East Antarctic Ice Divide such as Dome C, Dome F, Dome B and Vostok. These facts indicate that Dome A is the "pole of cold" on the Earth. The total amount of snow accumulation rate in 2005 and 2006 was only 0.16 cm, equaling 0.016 m water equivalent per year, the lowest precipitation ever recorded from Antarctica. Preliminary evidences indicate that Dome A is a candidate site for recovering the oldest ice core. 相似文献