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Identifying rock blocks based on hierarchical rock-mass structure model

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Science china Earth Sciences 2009年第10期52卷 1612-1623页

作者： XU NengXiong School of Engineering and Technology, china university of Geosciences, beijing 100083, china School of Engineering and Technology China University of Geosciences Beijing 100083 China

Rock-masses are divided into many closed blocks by deterministic and stochastic discontinuities and engineering interfaces in complex rock-mass engineering. Determining the sizes, shapes, and adjacent relations of blocks is important for stability analysis of fractured rock masses. Here we propose an algorithm for identifying spatial blocks based on a hierarchical 3D Rock-mass Structure Model (RSM). First, a model is built composed of deterministic discontinuities, engineering interfaces, and the earth's surface, and the deterministic blocks surrounded by these interfaces are traced. Then, in each deter-ministic block, a network model of stochastic discontinuities is built and the stochastic blocks are traced. Building a unitary wire frame that connects all interfaces seamlessly is the key for our algorithm to identify the above two kinds of blocks. Using this algorithm, geometric models can be built for block theory, discrete element method, and discontinuous deformation analysis.

关键词： rock-mass engineering discontinuity block identification 3D Rock-mass Structure Model network model of stochastic discontinuities

BINDING NUMBER AND MINIMUM DEGREE FOR [a,b]-FACTORS

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Systems Science and Mathematical Sciences 1993年第2期6卷 179-185页

作者： CHEN Ciping beijing agricultural Engineering university, beijing 100083, china

We give some sufficient conditions on the binding number and the minimumdegree for a graph to have an [a, b]-factor.

关键词： Graph factor binding number degree

A Novel network Management Model Based on XML for Service and Resource

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计算机工程 2002年第S1期28卷 77-81页

作者： ZHANG JinxiangWU JianpingWANG Jilong(network Research center of Tsinghua university, beijing 100084,china, jxzhang@***) network Research center of Tsinghua university Beijing 100084China j xzhang ***

XML can allow for the interchange of data between management applications using different information models. Furthermore, CORBA technique is increasingly used in the management of service and resource in the heterogeneous network environment. As the scheme of information arrangement of CORBA is flat file style, which handles querying, deleting, and insertinginformation inefficiently, this paper puts forward a novel network management model based on XML in the domain of the management of CERNET (china Education and Research network), which has used a tree structure of managed objects arrangement to provide efficient operation on managed objects. In addition, arrangement, definition, implementation and finding schemes for CORBA managed objects using XML are also given by the tree structure, and thus can arrange and retrieve managed objects efficiently.

关键词： XMLCORBAnetwork managementModel

Research on the method for retrieving soil moisture using thermal inertia model

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Science china Earth Sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2 1. Information College, South china agricultural university, Guangzhou 5106.2, china 2. Graduate university of Chinese Academy of Sciences, beijing 100049, china 1. Information College South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of Sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Comparison of Statistical Models for Regional Crop Trial Analysis

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agricultural Sciences in china 2002年第6期1卷 605-611页

作者： ZHANG Qun-yuan and KONG Fan-ling(College of Crop Science , china agricultural university ,beijing 100094 , P.R. china) College of Crop Science China Agricultural University Beijing 100094 P.R. China

Based on the review and comparison of main statistical analysis models for estimating variety-environment cell means in regional crop trials, a new statistical model, LR-PCA composite model was proposed, and the predictive precision of these models were compared by cross validation of an example data. Results showed that the order of model precision was LR-PCA model > AMMI model > PCA model > Treatment Means (TM) model > Linear Regression (LR) model > Additive Main Effects ANOVA model. The precision gain factor of LR-PCA model was 1.55, increasing by 8.4% compared with AMMI.

关键词： Crop breeding science Regional trial Statistical Model Predictive precision

A heuristic path-estimating algorithm for large-scale real-time traffic information calculating

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Science china(Technological Sciences) 2008年第S1期51卷 165-174页

作者： L WeiFeng1,ZHU TongYu1,WU DongDong2,DAI Hong3 & HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang university,beijing 100083,china 2 beijing Transportation Information center,beijing 100055,china 3 College of Arts & Science,beijing Union university,beijing 100083,china 1. State Key Laboratory for Software Development Environment Beihang University Beijing 100083 China 2. beijing Transportation Information center Beijing 100055 China 3. College of Arts & Science Beijing Union University Beijing 100083 China

As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.

关键词： path-estimating floating car data (FCD) road network vector GPS

Identification of differentially expressed genes in photo-period sensitive genic male sterile rice by randomly amplified cDNAs using RAPD primers

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Chinese Science Bulletin 1999年第4期44卷 348-351页

作者： JIANG Shuye, CHEN Qifeng and FANG Xuanjun Biotechnology Research center, Chinese Academy of agricultural Science, beijing 100081, china Institute of Genetics and Crop Breeding, Fujian agricultural university, Fuzhou 350002, china Corresponding author Biotechnology Research center Chinese Academy of Agricultural Science Beijing China Institute of Genetics and Crop Breeding Fujian Agricultural University Fuzhou China

The fertile and sterile young panicle representational populations were constructed by bulked sampling method using young panicles in the photo-period sensitive stage of fertility *** populations were analyzed using cDNA-RAPD. The results showed that: ( ⅰ ) bulked sampling method can be employed to analyze differentially expressed genes using cDNA-RAPD, taking an advantage in avoiding false positive caused by conventional sampling method. (ⅱ) Among 150 random primers used, 83 primers amplified the same banding patterns, and 34 primers amplified the same banding pattern but different staining of intensity on gel. ( ⅲ ) 33 primers amplified differential cDNA bands between fertile and sterile cDNA populations, and the ratio of polymorphism was 22%. It is concluded that there may exist a lot of genes relating to sterility, which makes the differentially expressed cDNA fragments complicated.

关键词： photo-period sensitive genie male sterile genes cDNA-RAPD differential display analysis.

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied Science School, university of Science and Technology beijing, beijing 100083, china) Applied Science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

RRM:An incentive reputation model for promoting good behaviors in distributed systems

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Science in china(Series F) 2008年第11期51卷 1871-1882页

作者： ZHANG Hong1,2,DUAN HaiXin1,3 & LIU Wu1,3 1 Tsinghua National Laboratory for Information Science and Technology,Tsinghua university,beijing 100084,china 2 Department of Computer Science and Technology,Tsinghua university,beijing 100084,china 3 {6. Research center,Tsinghua university,beijing 100084,china 1. Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China 2. Department of Computer Science and Technology Tsinghua University Beijing 100084 China 3. network Research center Tsinghua University Beijing 100084 China

Reputation systems represent soft security mechanisms that complement traditional information security mechanisms. They are now widely used in online e-commerce markets and communities in order to stimulate good behaviors as well as to restrain adverse behaviors. This paper analyzes the limitations of the conversational reputation models and proposes an incentive reputation model called the resilient reputation model （RRM） for the distributed reputation systems. The objective of this reputation model is not only to encourage the users to provide good services and, therefore, to maximize the probability of good transaction outcomes, but also to punish those adverse users who are trying to manipulate the application systems. The simulation results indicate that the proposed reputation model （RRM） could effectively resist against the common adverse behaviors, while protecting the profits of sincere users from being blemished by those adversaries.

关键词： reputation model distributed system trust soft security