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介绍了后门检测系统的设计,以及各模块实现拟采用的方案,包括:网卡数据包的截获,进程和端口号的映射,截获包的解码与分析和数据库设计等. 相似文献
954.
国际Argo计划执行现状剖析 总被引:1,自引:0,他引:1
国际Argo计划自2000年实施以来,世界上25个国家和团体已经在全球海洋中布放了5000余个Argo浮标,其中在海上正常工作的浮标已经超过3000个。这标志着全球Argo实时海洋观测网已经全面建成。文中将系统介绍国际Argo计划主要成员国在浮标布放、回收和Argo资料管理等方面所作出的贡献,以帮助读者对这21世纪的重大国际海洋观测计划有一较全面、深入的了解。 相似文献
955.
姑合工程实践,介绍快速“高真空击密法”软地基处理方法的施工原理、施工工艺及质量控制等,并简单阐述“高真空击密法”在进行软地基处理中的优点。 相似文献
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957.
In order to study the effects of different land vegetative covers on soil quality attributes, a loess hill slope was selected in eastern Golestan Province, Ghapan watershed, Iran. Four profiles in four land uses, including Quercus natural forest; Pinus artificial forest; Cupressus artificial forest and a cultivated land, were studied. Results showed that MWD was significantly different in the studied land uses, and it varied between 1.6 mm in Quercus natural forest and o.31 mm in cultivated land use. The lowest CEC, microbial respiration rate and organic carbon were 28.4 cmol·kg^1, 177 μgCO2·g^-1·day^-1 and 1.32 % found in cultivated land use, respectively. The organic matter was considerably higher content in the forest areas than that of cultivated land use. The studies on soil profile development revealed that the natural forest soils were highly developed. The soils of the Quercus natural forest were classified as Calcic Haploxeralfs with a well developed argillie horizon unlike the cultivated soils which showed the minimum development and classified as Typic Xerorthents. The soils of the artificial forests had both mollic epipedons and were classified as Typic Calcixerolls with moderate profile development. Micromorphological studies revealed that argillic horizons had speckled and partly crystallitic b-fabric in the natural forest indicating the high landscape stability. In contrast, the crystallitic b-fabric of other land uses shows the absence of enough leaching of carbonate and the subsequent migration of clay particles indicating the unstable conditions and high soil erosion. Intense erosion of the surface horizons of cultivated land use has resulted in the outcropping of the subsurface carbonate rich horizons preventing soil development. 相似文献
958.
A basinwide ocean general circulation model of the North Pacific is used to identify which location is more efficient for ocean CO2 sequestration in the North Pacific. Four injection depths at each one of fifteen locations are chosen. In terms of effectiveness index (EI) and escape factor (EF), it is clear that the effectiveness increases with increasing latitude at the end of the 50 a injection period. Sitebysite differences in the EI can be over 9% for the 1 000 m injection depth in the western North Pacific at the end of 50 a of continuous injection. The difference is much larger for the 500 m injection. The difference decreases with increasing injection depth. However, the sitebysite difference is small for the injection in the eastern North Pacific. The sequestration is more efficient for the injection in the east than in the west. For the 500 m injection depth, the difference in effectiveness between the west and the east is over 10% at the end of 50 a injection period. The largest concentration of sequestered CO2 increases with increasing injection depth. For the injection in both the western and central North Pacific, the largest exchange flux always appears to be at about 42°N, 150°E, whereas for the injection in the eastern area the large flux appears to be in the equatorial region (120°W). 相似文献
959.
为更好地贯彻落实省委关于在全省开展以“讲党性、树新风、优环境、促发展”为主题的作风建设活动的总体部署要求,近日,省国土资源厅制定了《活动方案》,号召全省各级国土资源部门以扩内需、保稳定、促发展为目标,进一步改进作风、提高能力、健全机制、形成氛围,为全省经济社会实现更好更快发展做出新的贡献。 相似文献
960.
为全面了解和掌握采矿权人矿产资源开发利用方案、年度开采设计实施情况,宝丰县国土资源局对2008年度辖区内的所有采矿权人进行了全面检查,并于日前圆满完成。 相似文献