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基于主客体安全性评估的访问控制模型

四川大学学报（工程科学版） 2011年第6期43卷 140-147页

作者：罗俊刘嘉勇龚勋胡勇四川大学信息安全研究所四川成都610041 四川大学计算机学院四川成都610065

从访问行为的主体和客体安全性出发,提出了一种基于主客体安全性评估的访问控制模型。定义了用户安全度、资源安全度、用户安全级别、资源安全级别和操作级别等概念及其相互关系,提出了用户以某种操作访问某系统资源需要满足的条件公式... 详细信息

从访问行为的主体和客体安全性出发,提出了一种基于主客体安全性评估的访问控制模型。定义了用户安全度、资源安全度、用户安全级别、资源安全级别和操作级别等概念及其相互关系,提出了用户以某种操作访问某系统资源需要满足的条件公式。通过威胁、脆弱性和环境安全性估值的加权求和得到用户所访问客体所在设备的安全性估值,即为客体安全度。访问行为的主体安全度则取决于用户所用物理设备的安全性、用户对资源使用的合规性、用户的历史表现、第三方对用户的评价以及用户身份凭证级别。讨论了这5个因素估值的计算方法,并采用加权和求得主体安全度。最后,在实际应用中对该访问控制模型进行了实验验证。统计数据表明,与基于防火墙和入侵检测的访问控制系统相比,采用基于主客体安全性评估的访问控制系统的安全事件无论从总数还是严重性上都有明显下降。

关键词：访问控制主体客体安全度安全级别

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地位与策略:“大调解”中的人民法院

法制与社会发展 2011年第6期17卷 23-36页

作者：王禄生四川大学法学院四川成都610064

本文是对当前部分地方推行的,力图追求法院在"大调解"中占据"主导"地位的本土实践的反思,并试图通过论述证明:法院在现有的制度环境下很难真正地扮演起"大调解"中的主导角色。这与执政党对法院的定位、社会公众对解纷机构的选择倾向和... 详细信息

本文是对当前部分地方推行的,力图追求法院在"大调解"中占据"主导"地位的本土实践的反思,并试图通过论述证明:法院在现有的制度环境下很难真正地扮演起"大调解"中的主导角色。这与执政党对法院的定位、社会公众对解纷机构的选择倾向和司法的固有限度息息相关。法院的这种角色决定了其在追求"大调解"格局"主导地位"过程中所采用的各种策略。这些策略的采用虽然极大提升了法院解决疑难纠纷的能力,但却同时进一步限制了法院对"主导地位"的追求。二律悖反的事实说明准确定位才是法院在"大调解"中发挥更大作用的基础和关键。

关键词：大调解法院的地位法院的策略资源依赖新制度主义

Nitrate Leaching in an Irrigated Wheat-Maize Rotation Field in the North China Plain

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Pedosphere 2005年第2期15卷 196-203页

作者： ZHANGYu-Ming HUChun-Sheng ZHANGJia-Bao CHENDe-Li LIXiao-Xin instituteofGeneticandDevelopmentalBiology ChineseAcademyofSciencesShijiazhuang050021（China） instituteofSoilScience ChineseAcademyofSciencesNanjing210008（China） DepartmentofresourcemanagementandHorticulture InstituteofLandandFoodResourcetheUniversityofMelbourneParkville3052Victoria（Australia）

Soil water deep drainage and nitrate (NO-3. leaching losses below the root zone were investigated in a 1 ha wheat-maize rotation field under traditional agricultural management that local farmers generally follow in the North China Plain, using the soil water balance method and NO3.N concentration in suction samples. Water drainage, and NO3.N distribution and leaching losses exhibited pronounced spatial and temporal variability. Soil water deep drainage and NO3.N leaching loss mostly occurred during the sum…

关键词： deep drainage nitrate leaching soil water

A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2,3.& BAO ShuMing1 1 The Key Lab of Poyang Lake Ecological Environment and resource Development, Jiangxi Normal University, Nanchang 3.0022, China 2 institute of Geographic Sciences and resources Research, Chinese Academy of Sciences, Beijing 100101, China 3.School of Geography and Environmental Sciences, Jiangxi Normal University, Nanchang 3.0022, China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 3., 2005 was combined with GIS thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by remote sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

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南盘江坳陷二叠系层序地层格架及古地理环境

沉积与特提斯地质 2004年第3期24卷 80-89页

作者：赖生华陈洪德余谦西南石油学院油气藏地质及开发工程国家重点实验室成都理工大学四川成都610059 成都地质矿产研究所四川成都610082

南盘江坳陷二叠系划分为12个三级层序,平均每个层序延续时限为3.a。进而将三级层序划分为4个Ⅰ型层序和8个Ⅱ型层序。三级层序虽然在不同地区发育完整性有所不同,但总体可以进行对比。三级层序构成两个超层序。超层序SS1沉积期,南盘江... 详细信息

南盘江坳陷二叠系划分为12个三级层序,平均每个层序延续时限为3.a。进而将三级层序划分为4个Ⅰ型层序和8个Ⅱ型层序。三级层序虽然在不同地区发育完整性有所不同,但总体可以进行对比。三级层序构成两个超层序。超层序SS1沉积期,南盘江坳陷主要为台、盆相间古地理格局,具有狭窄的台地边缘—台地斜坡沉积。钦防地区为半深海环境。超层序SS2沉积末期,右江地区从台、盆相间格局演化到盆包台格局。上扬子古陆主体为开阔台地—局限台地,而靠近川滇古陆则变为陆相环境。

关键词：南盘江坳陷二叠系层序地层古地理

Impacts of land Cover Changes on Runoff and Sediment in the Cedar Creek Watershed,*** River,Indiana,United States

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Journal of Mountain Science 2008年第2期5卷 113-121页

作者： JIANG Xiaobo Chi-hua Huang Fushui Ruan Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 Siehuan China USDA ARS National Soil Erosion Research Laboratory ~75 S Russell Street West Lafayette IN 47907 United States Water and Soil Conservative Department Fuzhou 35ooo3 Fujian China

The relation between runoff and sediment and land cover is investigated in the Cedar Creek Watershed （CCW）, located in Northeastern Indiana, United States. The major land cover types in this watershed are cultivated land, woodland and pasture /Conservation Reserve Program （CRP）, which account for approximate 90 % of the total area in the region. Moreover, land use was changed tremendously from aooo to 9004, even without regarding the effect of the crop rotation system （corn ＆ soybean）. At least 49 % of land cover types were changed into other types in this period. The land cover types, ranking by changing area from high to low series, are rye, soybean, corn, woodland and pasture/CRP. The CCW is divided into 21 subwatersheds, and soil and water loss in each sub-watershed is computed by using Soil and Water Assessment Tool （SWAT）. The results indicate that the variations in runoff and sediment have positive relation to the area of crops （especially corn and soybean）; sediment is more sensitive to land cover changes than runoff; more heavy rainfall does not always mean more runoff because the combination of different land cover types always modify runoff coefficient; and rye, soybean and corn are the key land cover types, which affected the variation in runoff and sediment in the CCW.

关键词： Cedar Creek watershed Soil and Water Assessment Tool land cover change runoff sediment

SOIL CONSERVATION EFFICIENCY OF DIFFERENT MODELS CONVERTING FROM STEEP FARMING SLOPE PLOTS IN YA'AN, sichuan, CHINA

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International Journal of Sediment Research 2003年第4期18卷 340-345页

作者： Yulin DENG, Yan PENG, Yukuan WANG and Zongting YANG institute of Mountain Hazards and Environment, Chinese Academy of sichuan 610041, P. R. China College of Forestry and Horticulture of sichuan Agricultural University, sichuan 625000, P. R. China. Water resources Administration in Ya'an, sichuan 625000, P. R. China. institute of Mountain Hazards and Environment Chinese Academy of Sichuan 610041 P. R. China College of Forestry and Horticulture of sichuan Agricultural University Sichuan 625000 P. R. China College of Forestry and Horticulture of sichuan Agricultural University Sichuan 625000 P. R. China institute of Mountain Hazards and Environment Chinese Academy of Sichuan 610041 P. R. China Water resources Administration in Ya'an Sichuan625000P.R.China

Converting farming slope land into artificial forestland or grassland is a major measure of soil/water conservation. Five conversion practices, namely, 1) a control plot still tilled with a crop (maize), 2) a folder grass-growing plot seeded with Lolium perenne , 3. a young alder tree-growing plot, 4) a pear orchard plot and 5)a bamboo plot intercropped with folder grass, were monitored to compare the soil conservation efficiency of those changes in Ya'an,{3.for 3.years between September 1998 and August 2001. Results showed that the 5 designed converting models functioned differently in erosion control. The most effective model was bamboo groves intercropped with folder grass (Lolium perenne). The folder grass (Lolium perenne) growing model was more effective than the pure pear orchard model. The least effective model was the young alder tree-growing slope, which was even less effective than the control (a slope without converted cultivation). Meanwhile, changes in the soil's physical properties r

关键词： Soil and water conservation effect. Watershed land use. sichuan Province

Study on Moist-locking mining technique of Cool Water well coal mine

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Study on Moist-locking mining technique of Cool Water well c...

2011 International Symposium on Water resource and Environmental Protection(ISWREP 2011)

作者： Liu Yujie sichuan traffic vocational technical college road and bridge department sichuan traffic vocational technical college chengdu china Fan Limin Shaanxi geological survey {3. Xian TangYanLu shaanxi geology survey {3. Xian china Nie Zhongquan sichuan traffic vocational technical college road and bridge department sichuan traffic vocational technical college chengdu china Liu Guodong sichuan University {3. of water conservancy and electric power chengdu china

Cool water Wells coal mine is a modern large mine in Shaanxi Yulin-Shenmu coal mine areas. Coal mining had caused serious destruction and pollution to local geological environment and threatened the groundwater resources. If it couldn’t control properly, the great accidents would be caused easily and even influence the development of mining cities later. Therefore, the paper puts forward some measures to protect groundwater resources and reasonable utilization of coal gangue, according to cool water well coal mine’s environmental geological characteristics, which had important practical significance to mine construction and environmental protection.

关键词： Cool Water well coal mine groundwater resource gangue mining measures Moist-locking mining technique

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中国山地范围界定的初步意见

山地学报 2008年第2期26卷 129-136页

作者：江晓波中国科学院水利部成都山地灾害与环境研究所中国科学院山地灾害与地表过程重点实验室四川成都610041

中国山地的范围一直缺乏可操作的、准确的量化方法,从而导致对山地及其内部资源、环境、人口和发展问题认识的不全面。同时,准确界定山地范围是实施数字山地战略的一项基础性工作。在前人研究的基础上,采用两种方案确定中国山地范围。... 详细信息

中国山地的范围一直缺乏可操作的、准确的量化方法,从而导致对山地及其内部资源、环境、人口和发展问题认识的不全面。同时,准确界定山地范围是实施数字山地战略的一项基础性工作。在前人研究的基础上,采用两种方案确定中国山地范围。方案一:将满足以下两种情况的国土界定为山地,1)海拔≥3.00m;2)海拔≥3.0～3.00m,同时相对高差>200m或坡度>25°。根据此标准计算,中国山地面积为4000265km2,占中国陆地面积的41.67%。方案二:根据UNEP-WCMC的标准,将满足下述情况的国土定义为山地,1)海拔≥2500m;2)海拔≥1500～2500m,坡度≥2°;3.海拔≥1000～1500m,坡度≥5°或相对高差≥3.0m;4)海拔≥3.0～1000m,相对高差≥3.0m。根据此标准计算,中国山地面积为442613.km2,占中国陆地面积的46.11%。按两种方法计算所得的分省山地面积中,前5名都是西藏、青海、新疆、四川和云南。将两种方案计算的山地面积按高程划分为六级:①3.0～1000m(含3.0m),②1000～1500m(含1000m),③1500～2500m(含1500m),④2500～3.00m(含2500m),⑤3.00～4500m(含3.00m),⑥≥4500m。根据两种方案的定义,海拔3.00m以上的山地面积相等;除了方案一在3.0～1000m间山地较方案二多3.4508km2外,其余几个级别山地的面积均为方案二大于方案一的山地面积,其中2500～3.00m间多13.43.km2,1500～2500m间多3.6186km2,1000～1500m间多282273.m2。

关键词：山地范围定义数字山地中国