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41.
对"基于角色的访问控制"方法进行扩展,提出"基于规则和角色的访问控制"方法.在此基础上,研制出一个.Net框架下信息管理系统的访问控制解决方案.该方案通过为客体(页面或其它类对象)绑定若干访问控制列表(Access Control List,ACL),再利用可视化编辑器来设置ACL,以实现对系统功能的动态配置,最终完成对用户访问权限的灵活管理. 相似文献
42.
To quantitatively analyze the response of distributions and hydrogen isotopic compositions （SD） of plant leaf wax to moisture, and to better understand their implications for paleoclimatic reconstruction, we measured av- erage chain length （ACL） and 8D values of n-alkanes and n-fatty acids （n-FAs） from Orinus kokonorica, a typical and representative plant in Lake Qinghai area, along a distance transect extending from lakeshore to wetland to dry- land in the arid ecosystem. The results showed that the ACL values of n-alkanes and n-FAs were negatively corre- lated with soil water content （SWC） with R2~0.593 and R2=0.924, respectively. This is as a result of plant＇s response to water loss with more abundance in long-chain n-alkyl lipids under increasing aridity by analyzing relationships between the molecular ratios of long-chain n-alkyl lipids （n-alkanes and n-FAs） from O. kokonorica and SWC. The 8D values of C29 n-alkane and C28 n-FA were also negatively correlated with SWC with R2-0.778 and R2-0.760, respectively, which may due to enhanced D-enrichment in leaf water by evapotranspiration （soil water evaporation and leaf water transpiration） with increasing aridity. Our results demonstrated that moisture exerts a significant con- trol on the ACL and 8D values from O. kokonorica in an arid ecosystem. This preliminary study on a modern single plant （O. kokonorica） sets a foundation for comprehending these values as quantitative proxies for paleo-humidity reconstruction. 相似文献