选取河南省域为研究区,利用RS(Remote Sensing)技术对18个省辖市土地利用的遥感影像数据进行处理,得到监督分类结果,运用GIS(Geographic Information System)技术对监督分类结果进行分析,并用经典的土壤构成组分多样性算法计算丰富度指...选取河南省域为研究区,利用RS(Remote Sensing)技术对18个省辖市土地利用的遥感影像数据进行处理,得到监督分类结果,运用GIS(Geographic Information System)技术对监督分类结果进行分析,并用经典的土壤构成组分多样性算法计算丰富度指数S、多样性指数H'和均匀度指数E。结果表明,各省辖市6种土地利用类型均匀度指数的范围为[0.265,0.647],济源市各土地利用类型分布最为均匀,周口市分布较为集中,均匀度最低。再将6种土地利用类型分别与均匀度指数E拟合函数进行分析,得出平均决定系数R^2的范围是[0.180,0.894],耕地与均匀度指数的拟合程度最高,而城镇建筑用地与均匀度指数的拟合效果最低;用6种土地利用类型分别与均匀度指数做相关分析,得出耕地和林地与均匀度指数的相关系数较高,城镇建筑用地与均匀度指数的相关系数最低,这与拟合函数分析的结果基本一致,说明耕地分布比较均匀而城镇建筑用地分布相对集中。展开更多
TA2/TA15 graded structural material（GSM） was fabricated by the laser additive manufacturing（LAM） process. The chemical composition, microstructure and micro-hardness of the as-deposited GSM were investigated. The ...TA2/TA15 graded structural material（GSM） was fabricated by the laser additive manufacturing（LAM） process. The chemical composition, microstructure and micro-hardness of the as-deposited GSM were investigated. The results show that the TA2 part of exhibiting near-equiaxed grains was Widmanst？tten α-laths microstructure. The TA15 part containing large columnar grains was fine basket-weave microstructure. The graded zone was divided into four deposited layers with 3000 μm in thickness. As the distance from the TA2 part increases, the alloy element contents and the β phase volume fraction increase, the α phase volume fraction decreases and the microstructure shows the evolution from Widmanst？tten α-laths to basket-weave α-laths gradually. The micro-hardness increases from the TA2 part to the TA15 part due to the solid solution strengthening and grain boundary strengthening.展开更多
Based on the analysis of several objective functions,a new method was proposed.Firstly,the feature of the inclination curve was analyzed.On this basis,the soil could be divided into several blocks with different displ...Based on the analysis of several objective functions,a new method was proposed.Firstly,the feature of the inclination curve was analyzed.On this basis,the soil could be divided into several blocks with different displacements and deformations.Then,the method of the soil division was presented,and the characteristic of single soil block was studied.The displacement of the block had two components:sliding and deformation.Moreover,a new objective function was constructed according to the deformation of the soil block.Finally,the sensitivities of the objective functions by traditional method and the new method were calculated,respectively.The result shows that the new objective function is more sensitive to mechanical parameters and the inversion result is close to that obtained by the large direct shear apparatus.So,this method can be used in slope back analysis and its effectiveness is proved.展开更多
Network virtualization is an enabling technology of running multiple virtual networks on a shared substrate network. It aims to deal with the ossification of current network architecture. As a crucial component of net...Network virtualization is an enabling technology of running multiple virtual networks on a shared substrate network. It aims to deal with the ossification of current network architecture. As a crucial component of network virtualization, virtual network embedding(VNE) can efficiently and effectively allocates the substrate resource to proposed virtual network requests. According to the optimization strategy, VNE approaches can be classified into three categories: exact, heuristic and meta-heuristic solution. The VNE exact solution is the foundation of its corresponding heuristic and meta-heuristic solutions. This paper presents a survey of existing typical VNE exact solutions, and open problems for the future research of VNE exact solutions are proposed.展开更多
The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from t...The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from the land utilization perspective, involving changes in grain production per unit area, multi-cropping index, and adjustment of agricultural structure. Compared with the record values, different research methodologies are used to analyze the po- tential of above three components. The results indicate that grain production potential of 65.68×109kg was unexploited in 2006, in which 45.8×109kg came from the restructuring in agriculture. So we can infer that the reduction of grain production in China could be primarily attributed to agricultural restructuring in recent years. So the productive poten- tial can be fully restored by increasing agricultural investment, or recovering agricultural structure in favorable condi- tions. So we can say that China’s current condition of food security is good.展开更多
How to keep cloud data intact and available to users is a problem to be solved. Authenticated skip list is an important data structure used in cloud data integrity verification. How to get the membership proof of the ...How to keep cloud data intact and available to users is a problem to be solved. Authenticated skip list is an important data structure used in cloud data integrity verification. How to get the membership proof of the element in authenticated skip list efficiently is an important part of authentication. Kaouthar Blibech and Alban Gabillon proposed a head proof and a tail proof algorithms for the membership proof of elements in the authenticated skip list. However, the proposed algorithms are uncorrelated each other and need plateau function. We propose a new algorithm for computing the membership proof for elements in the authenticated skip list by using two stacks, one is for storing traversal chain of leaf node, the other is for storing authentication path for the leaf. The proposed algorithm is simple and effective without needing plateau function. It can also be applicable for other similar binary hash trees.展开更多
文摘选取河南省域为研究区,利用RS(Remote Sensing)技术对18个省辖市土地利用的遥感影像数据进行处理,得到监督分类结果,运用GIS(Geographic Information System)技术对监督分类结果进行分析,并用经典的土壤构成组分多样性算法计算丰富度指数S、多样性指数H'和均匀度指数E。结果表明,各省辖市6种土地利用类型均匀度指数的范围为[0.265,0.647],济源市各土地利用类型分布最为均匀,周口市分布较为集中,均匀度最低。再将6种土地利用类型分别与均匀度指数E拟合函数进行分析,得出平均决定系数R^2的范围是[0.180,0.894],耕地与均匀度指数的拟合程度最高,而城镇建筑用地与均匀度指数的拟合效果最低;用6种土地利用类型分别与均匀度指数做相关分析,得出耕地和林地与均匀度指数的相关系数较高,城镇建筑用地与均匀度指数的相关系数最低,这与拟合函数分析的结果基本一致,说明耕地分布比较均匀而城镇建筑用地分布相对集中。
基金Project(2010CB731705)supported by the National Basic Research Program of China
文摘TA2/TA15 graded structural material（GSM） was fabricated by the laser additive manufacturing（LAM） process. The chemical composition, microstructure and micro-hardness of the as-deposited GSM were investigated. The results show that the TA2 part of exhibiting near-equiaxed grains was Widmanst？tten α-laths microstructure. The TA15 part containing large columnar grains was fine basket-weave microstructure. The graded zone was divided into four deposited layers with 3000 μm in thickness. As the distance from the TA2 part increases, the alloy element contents and the β phase volume fraction increase, the α phase volume fraction decreases and the microstructure shows the evolution from Widmanst？tten α-laths to basket-weave α-laths gradually. The micro-hardness increases from the TA2 part to the TA15 part due to the solid solution strengthening and grain boundary strengthening.
基金Projects(2013CB036004,2011CB710601)supported by the National Basic Research Program of ChinaProject(51178468)supported by the National Natural Science Foundation of ChinaProject(CX2011B096)supported by Hunan Provincial Postgraduate Innovation Program,China
文摘Based on the analysis of several objective functions,a new method was proposed.Firstly,the feature of the inclination curve was analyzed.On this basis,the soil could be divided into several blocks with different displacements and deformations.Then,the method of the soil division was presented,and the characteristic of single soil block was studied.The displacement of the block had two components:sliding and deformation.Moreover,a new objective function was constructed according to the deformation of the soil block.Finally,the sensitivities of the objective functions by traditional method and the new method were calculated,respectively.The result shows that the new objective function is more sensitive to mechanical parameters and the inversion result is close to that obtained by the large direct shear apparatus.So,this method can be used in slope back analysis and its effectiveness is proved.
基金supported by the National Basic Research Program of China(973 Program)under Grant 2013CB329104the National Natural Science Foundation of China under Grants 61372124 and 61427801the Key Projects of Natural Science Foundation of Jiangsu University under Grant 11KJA510001
文摘Network virtualization is an enabling technology of running multiple virtual networks on a shared substrate network. It aims to deal with the ossification of current network architecture. As a crucial component of network virtualization, virtual network embedding(VNE) can efficiently and effectively allocates the substrate resource to proposed virtual network requests. According to the optimization strategy, VNE approaches can be classified into three categories: exact, heuristic and meta-heuristic solution. The VNE exact solution is the foundation of its corresponding heuristic and meta-heuristic solutions. This paper presents a survey of existing typical VNE exact solutions, and open problems for the future research of VNE exact solutions are proposed.
基金Under the auspices of National Key Technologies R&D Program of China (No. 2006BAB15B02)National Natural Science Foundation of China (No. 40671009)
文摘The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from the land utilization perspective, involving changes in grain production per unit area, multi-cropping index, and adjustment of agricultural structure. Compared with the record values, different research methodologies are used to analyze the po- tential of above three components. The results indicate that grain production potential of 65.68×109kg was unexploited in 2006, in which 45.8×109kg came from the restructuring in agriculture. So we can infer that the reduction of grain production in China could be primarily attributed to agricultural restructuring in recent years. So the productive poten- tial can be fully restored by increasing agricultural investment, or recovering agricultural structure in favorable condi- tions. So we can say that China’s current condition of food security is good.
基金partially supported by the Fundamental Research Funds for the Central Universities of China under Grant No.2015JBM034the China Scholarship Council Funds under File No.201407095023
文摘How to keep cloud data intact and available to users is a problem to be solved. Authenticated skip list is an important data structure used in cloud data integrity verification. How to get the membership proof of the element in authenticated skip list efficiently is an important part of authentication. Kaouthar Blibech and Alban Gabillon proposed a head proof and a tail proof algorithms for the membership proof of elements in the authenticated skip list. However, the proposed algorithms are uncorrelated each other and need plateau function. We propose a new algorithm for computing the membership proof for elements in the authenticated skip list by using two stacks, one is for storing traversal chain of leaf node, the other is for storing authentication path for the leaf. The proposed algorithm is simple and effective without needing plateau function. It can also be applicable for other similar binary hash trees.
