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Remote Sense and GIS-Based Division of Landslide Hazard Degree in Wanzhou District of the Three Gorges Reservoir Area 被引量:1
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作者 ZHOU Qigang FENG Wenlan +2 位作者 SONG Shujun YUAN Lifeng ZHOU Wancun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期780-786,共7页
An evaluation model divided landslide hazard degrees in Wanzhou District of Three Gorges Reservoir Area. The model was established by GIS techniques and took land use/cover, stratum characters, slope aspect, slope gra... An evaluation model divided landslide hazard degrees in Wanzhou District of Three Gorges Reservoir Area. The model was established by GIS techniques and took land use/cover, stratum characters, slope aspect, slope gradient, elevation difference and slope shape as evaluation factors. The data of land use/cover were obtained by remote sensing, and the weights of the factors mentioned above were established by the analytic hierarchy process (AHP). The results indicate, low danger areas in the studied area account for 66.51%, and high danger areas and very high danger areas occupy 1/3 of the total area. The regions of high and very high danger are mainly located around the urban area of Wanzhou District and on the banks of the Yangtze River with a relatively large area, where collapse and landslide directly threats densely populated areas and Three Gorges Reservoir. Slope destabilization, if occurs, will bring huge loss to social economy. All research results are consistent with the actual conditions; therefore, they can be regarded as a useful basis for planning and constructing of the reservoir area. 展开更多
关键词 landslide hazard degree three gorges reservoir area LANDSLIDE remote sense geography information system
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Selection Method of Evaluation Indicators with Three-Parameter Interval Grey Number 被引量:1
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作者 Fanlin Meng Na Wang Bingjun Li 《Open Journal of Applied Sciences》 2015年第12期833-840,共8页
The evaluation problem with three-parameter interval grey number (T-PIGN) widely exists in real world. To select effective evaluation indicators of the problem, this paper puts forward evaluation index system selectio... The evaluation problem with three-parameter interval grey number (T-PIGN) widely exists in real world. To select effective evaluation indicators of the problem, this paper puts forward evaluation index system selection principle of T-PIGN based on distance entropy model, and gives out evaluation index system selection judgment criterion of T-PIGN. Furthermore, for the redundancy of evaluation index system with T-PIGN, a selection method of evaluation index system with T-PIGN is proposed. Finally, the applicability of the proposed method is verified by concrete examples. 展开更多
关键词 Evaluation INDICATORS Selection three-Parameter interval GREY NUMBER GREY DISTANCE ENTROPY
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An Evaluation Algorithm for Importance of Dynamic Nodes in Social Networks Based on Three-Dimensional Grey Relational Degree
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作者 Xiaolong Li Yiliang Han +1 位作者 Deyang Zhang Xuguang Wu 《国际计算机前沿大会会议论文集》 2018年第2期18-18,共1页
关键词 Social networks DYNAMIC nodesthree-dimensional GREY RELATIONAL degree
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Design and Analysis of a Magnetic Bearings with Three Degrees of Freedom 被引量:1
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作者 Ye Yuan Yukun Sun Qianwen Xiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期142-151,共10页
The current research of supporting and transmission system in flywheel energy storage system(FESS) focuses on the low consumption design. However, friction loss is a non-negligible factor in the high-speed but lightwe... The current research of supporting and transmission system in flywheel energy storage system(FESS) focuses on the low consumption design. However, friction loss is a non-negligible factor in the high-speed but lightweight FESS energy and momentum storage with mechanical-type supporting system. In order to realize the support system without mechanical loss and to maximize the e ciency of the flywheel battery, a permanent magnet biased magnetic bearings(PMBMB) is applied to the FESS with the advantages of low loss, high critical speed, flexible controllability and compact structure. In this frame, the relevant research of three degrees of freedom(3-DOF) PMBMB for a new type FESS is carried out around the working principle, structural composition, coupling characteristics analysis, mathematical model, and structural design. In order to verify the performance of the 3-DOF PMBMB, the radial force mathematical model and the coupling determination equations of radial two DOF are calculated according to an equivalent magnetic circuit, and radial–axial coupling is analyzed through finite element analysis. Moreover, a control system is presented to solve the control problems in practical applications. The rotor returns to the balanced position in 0.05 s and maintains stable suspension. The displacement fluctuation is approximately 40 μm in the y direction and 30 μm in the x direction. Test results indicate that the dynamic rotor of the proposed flywheel energy storage system with PMBMB has excellent characteristics, such as good start-of-suspension performance and stable suspension characteristics. The proposed research provides the instruction to design and control a low loss support system for FESS. 展开更多
关键词 FLYWHEEL energy storage system Magnetic bearings degreeS of FREEDOM Coupling FINITE ELEMENT analysis
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让你过把DJ瘾——Three Degrees
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作者 冰河洗剑 《网友世界》 2004年第8期40-41,共2页
将电脑中的音乐与其它用户共享,让网上的朋友收听,老办法就是架高一个流媒体服务器。但是,随着P2P技术的发展,音乐共享又有了新方式。想不想与朋友一起来过把DJ瘾?来跟我看看奇妙的P2P即时通讯工具“3度Three Degrees”吧!
关键词 P2P技术 即时通讯工具 “3度 three degrees” MSN MESSENGER “3度”组 动画/照片发送 即时聊天工具 音乐混合功能
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Degree of polarization based on the three-component pBRDF model for metallic materials 被引量:5
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作者 王凯 朱京平 刘宏 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期254-259,共6页
An expression of degree of polarization(DOP) for metallic material is presented based on the three-component polarized bidirectional reflectance distribution function(p BRDF) model with considering specular reflec... An expression of degree of polarization(DOP) for metallic material is presented based on the three-component polarized bidirectional reflectance distribution function(p BRDF) model with considering specular reflection, directional diffuse reflection and ideal diffuse reflection. The three-component p BRDF model with a detailed reflection assumption is validated by comparing simulations with measurements. The DOP expression presented in this paper is related to surface roughness, which makes it more reasonable in physics. Test results for two metallic samples show that the DOP based on the three-component p BRDF model accords well with the measurement and the error of existing DOP expression is significantly reduced by introducing the diffuse reflection. It indicates that our DOP expression describes the polarized reflection properties of metallic surfaces more accurately. 展开更多
关键词 degree of polarization(DOP) polarized bidirectional reflectance distribution function(pBRDF) metallic materials
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A novel two-degree-of-freedom spherical ultrasonic motor using three travelling-wave type annular stators 被引量:5
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作者 王剑 胡锡幸 +1 位作者 王班 郭吉丰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1298-1306,共9页
In order to promote the tolerance and controllability of the multi-degree-of-freedom(M-DOF) ultrasonic motor, a novel two-degree-of-freedom(2-DOF) spherical ultrasonic motor using three traveling-wave type annular sta... In order to promote the tolerance and controllability of the multi-degree-of-freedom(M-DOF) ultrasonic motor, a novel two-degree-of-freedom(2-DOF) spherical ultrasonic motor using three traveling-wave type annular stators was put forward. Firstly,the structure and working principle of this motor were introduced, especially a spiral spring as the preload applied component was designed for adaptive adjustment. Then, the friction drive model of 2-DOF spherical motor was built up from spatial geometric relation between three annular stators and the spherical rotor which was used to analyze the mechanical characteristics of the motor.The optimal control strategy for minimum norm solution of three stators' angular velocity was proposed, using Moore-Penrose generalized inverse matrix. Finally, a 2-DOF prototype was fabricated and tested, which ran stably and controllably. The maximum no-load velocity and stall torque are 92 r/min and 90 m N·m, respectively. The 2-DOF spherical ultrasonic motor has compact structure, easy assembly, good performance and stable operation. 展开更多
关键词 球形电动机 超声波马达 电机定子 两自由度 行波型 环形 2自由度 最优控制策略
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Three vertex degree correlations of fixed act-size collaboration networks
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作者 雷敏 赵清贵 侯振挺 《Journal of Central South University》 SCIE EI CAS 2011年第3期830-833,共4页
A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on ... A rate equation approach was presented for the exact computation of the three vertex degree correlations of the fixed act-size collaboration networks.Measurements of the three vertex degree correlations were based on a rate equation in the continuous degree and time approximation for the average degree of the nearest neighbors of vertices of degree k,with an appropriate boundary condition.The rate equation proposed can be generalized in more sophisticated growing network models,and also extended to deal with related correlation measurements.Finally,in order to check the theoretical prediction,a numerical example was solved to demonstrate the performance of the degree correlation function. 展开更多
关键词 网络模型 顶点度 固定法 协作 速率方程 相关测量 边界条件 理论预测
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Positive solutions of three-point boundary value problems 被引量:1
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作者 缪烨红 张吉慧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第6期817-823,共7页
In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in... In this paper, we consider existence of single or multiple positive solutions of three-point boundary value problems involving one-dimensional p-Laplacian. We then study existence of solutions when the problems are in resonance cases. The proposed approach is based on the Krasnoselskii's fixed point theorem and the coincidence degree. 展开更多
关键词 three-point boundary value problems positive solution fixed point theorem coincidence degree theorem
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Relations between Mountain Settlements and Geographic Factors in Three Gorges Reservoir Area
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作者 罗勇 于慧 +2 位作者 王勇 郑志军 王晓 《Journal of Donghua University(English Edition)》 EI CAS 2015年第4期571-576,共6页
Compared with previous studies,the research attempted to establish the appropriate quantitative models to explain the relations between settlement density Diand geographic factors,which could make a scientific guidanc... Compared with previous studies,the research attempted to establish the appropriate quantitative models to explain the relations between settlement density Diand geographic factors,which could make a scientific guidance to the mountain settlements planning. Five factors,including slope,relief amplitude,distance to river, distance to cultivated land, and distance to road, were identified through principal component analysis( PCA). The inherent relations between five factors and Di( settlement density)were modeled by regression analysis. The results are as follows.( 1) The associations among Diand slope,relief amplitude,river,road are better modeled by the exponential decay line; with the buffer distance of slope, relief amplitude, distance to river and distance to road increasing, Didecreases.( 2) The associations between Diand cultivated land are better modeled by the quadratic polynomial line; with the buffer distance of cultivated land increasing,Diincreases first, and then dramatically decreases.( 3) The area within 500 m from the road,within 500 m from the cultivated land,within 1 600 m from the river,within the relief amplitude of 30-200 m,and the area within the slope of 0°-10° are the fitting land for settlements,and it is very important to lay the mountain settlements on those optimized regions. 展开更多
关键词 three G orges RESERVOIR area SETTLEMENT AGGREGATION degree spatial distribution characteristic
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EXISTENCE OF THREE-SOLUTIONS FOR SECOND-ORDER DIFFERENTIAL EQUATIONS WITH NONLINEAR BOUNDARY VALUE CONDITIONS
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作者 Liu BinDept.ofMath.,HuazhongUniv.ofScienceandTechnology,Wuhan430074,China.CollegeofMath.andStatist.,WuhanUniv.,Wuhan430072,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期135-144,共10页
The paper deals with the existence of three- solutions for the second- order differential equations with nonlinear boundary value conditions x″=f(t,x,x′) , t∈ [a,b], g1(x(a) ,x′(a) ) =0 , g2 (x(b) ,x′(... The paper deals with the existence of three- solutions for the second- order differential equations with nonlinear boundary value conditions x″=f(t,x,x′) , t∈ [a,b], g1(x(a) ,x′(a) ) =0 , g2 (x(b) ,x′(b) ) =0 , where f :[a,b]× R1× R1→ R1,gi:R1× R1→ R1(i=1 ,2 ) are continuous functions.The methods employed are the coincidence degree theory.As an application,the sufficient conditions under which there are arbitrary odd solutions for the BVP are obtained 展开更多
关键词 coincidence degree three- solutions theorem nonlinear boundary value conditions
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An investigation of weed seed banks reveals similar potential weed community diversity among three different farmland types in Anhui Province, China 被引量:4
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作者 HE Yun-he GAO Ping-lei QIANG Sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第4期927-937,共11页
Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey ... Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey of weed seed banks was conducted in 2 280 fields at 228 sites of 62 locations representing three different types of farmland(95 paddy, 73 summer-ripe, and 60 autumn-ripe farmlands) along the bank of the Yangtze River in Anhui Province, China. A total of 43 families and 174 species of weeds were found in these weed seed banks. A comparison of the composition of weed groups in the seed banks showed that the species number and density percentage of grass, sedge and broadleaf weed groups were similar among the different types of farmland. The seed banks of all three farmland types shared 71 common weed species, accounting for 40.80% of the total number of species. These common weeds, which were both associated and not associated with crops, accounted for 91.71% of the total dominance degree among all farmland types. The crop-associated weed species were distributed in all soil layers of each farmland type. The Shannon-Wiener index H′(description of species diversity which is more sensitive to dense species) and Pielou's evenness index J(description of species evenness) in summer-ripe farmland were similar to those in autumn-ripe farmland but differed from those in paddy farmland. However, the Simpson's index D(description of species diversity which is more sensitive to sparse species) was similar among all three farmland types. The results of similarity comparison indicated that although the aboveground weed community differed among the different cropping patterns, the weed species composition in the soil seed bank was still similar. Consequently, our results demonstrate that after the implementation of long-term monoculture patterns, weed species compositions in the soil seed bank in different farmlands become homogenized regardless of the crop type. 展开更多
关键词 species compositi on domi nance degree COMM UNITY similarity COMM UNITY variati on ANHUI Province
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Quantitative Trait Loci for Grain Chalkiness and Endosperm Transparency Detected in Three Recombinant Inbred Line Populations of Indica Rice 被引量:19
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作者 MEI De-yong ZHU Yu-jun +3 位作者 YU Yong-hong FAN Ye-yang HUANG De-run ZHUANG Jie-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期1-11,共11页
Quantitative trait loci(QTL) for percentage of chalky grain,degree of chalkiness,and endosperm transparency were detected using 3 recombinant inbred line populations derived from crosses between parental lines of co... Quantitative trait loci(QTL) for percentage of chalky grain,degree of chalkiness,and endosperm transparency were detected using 3 recombinant inbred line populations derived from crosses between parental lines of commercial three-line hybrids of indica rice.Two of the populations showed great variations on heading date,and the other had a short range of heading date variation.A total of 40 QTLs were detected and fell into 15 regions of 10 chromosomes,of which 5 regions were detected for 1 or more same traits over different populations,2 were detected for different traits in different populations,3 were detected for 2 or all the 3 traits in a single population,and 5 were detected for a single trait in a single population.Most of these QTLs have been reported previously,but a region located on the long arm of chromosome 10 showing significant effects in all the 3 populations has not been reported before.It was shown that a number of gene cloned,including the Wx and Alk for the physiochemical property of rice grain,and GW2,GS3 and GW5 for grain weight and grain size,could have played important roles for the genetic control of grain chalkiness in rice,but there are many more QTLs exerting stable effects for rice chalkiness over different genetic backgrounds.It is worth paying more attentions to these regions which harbor QTL such as the qPCG5.2/qDC5.2/qET5.2 and qPCG10/qDC10/qET10 detected in our study.Our results also showed that the use of segregating populations having high-uniform heading date could greatly increase the efficiency of the identification of QTL responsible for traits that are subjected to great environmental influence. 展开更多
关键词 percentage of chalky grain degree of chalkiness endosperm transparency quantitative trait locus headingdate variation indica rice(Oryza sativa L.subsp.indica)
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Existence of Solutions of Three-Dimensional Fractional Differential Systems
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作者 Vadivel Sadhasivam Jayapal Kavitha Muthusamy Deepa 《Applied Mathematics》 2017年第2期193-208,共16页
In this article, we consider the three-dimensional fractional differential system of the form together with the Neumann boundary conditions,? where are the standard Caputo fractional derivatives, . A new result on the... In this article, we consider the three-dimensional fractional differential system of the form together with the Neumann boundary conditions,? where are the standard Caputo fractional derivatives, . A new result on the existence of solutions for a class of fractional differential system is obtained by using Mawhin’s coincidence degree theory. Suitable examples are given to illustrate the main results. 展开更多
关键词 FRACTIONAL DIFFERENTIAL EQUATIONS BOUNDARY Value Problem COINCIDENCE degree Theory
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THE ANALYSES OF THE THREE-DIMENSIONAL STRESS STRUCTURE NEAR THE CRACK TIP OF MODE Ⅰ CT SPECIMENS IN ELASTICPLASTIC STATE(Ⅱ)—THE ANALYSES OF THE STRESS STRUCTURE
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作者 岳珠峰 郑长卿 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第9期817-828,共12页
Based on [1], the stress structures of the smooth region and shear lip of the specimens have been investigated in the paper.The characteristics of the stress structure in the smooth region have been found that the var... Based on [1], the stress structures of the smooth region and shear lip of the specimens have been investigated in the paper.The characteristics of the stress structure in the smooth region have been found that the variable z can separated out; the stresses in the midsection can be obtained by the plane strain FEM results or HRR structure modified by the stress triaxiality. The effects of load level and thickness on the stress structure can be reflected by the distribution of CTOD along the thickness direction. The obtained expressions of the stresses are very simple and visualized. The analyses of the stress structure in the shear lip show that the stresses can be obtained by different methods of interpolation to a certain precise degree.A new degree parameter of the plane strain state has been put forward and studied. The parameter can reflect relatively well the variation of the kind and thickness of the specimen as well as the load level. The fracture parameter has also been investigated to be sure that it can be obtained by modified CTOD with the stress triaxiality. 展开更多
关键词 stress structure SINGULARITY Z_1 region stress triaxiality CTOD shear lip interpolative method degree parameter of the plane strain state
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Topological Configuration and Rotation Analysis of the Three⁃Order Rubik􀆳s Cube
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作者 Yulei Hou Ting Zhou +2 位作者 Guoxing Zhang Ming Li Daxing Zeng 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第5期49-58,共10页
The mechanism of three⁃order Rubik􀆳s Cube(RC)has the characteristics of recombination and variable degree of freedom,and it is difficult to accurately describe the degree of its freedom.This paper takes RC as... The mechanism of three⁃order Rubik􀆳s Cube(RC)has the characteristics of recombination and variable degree of freedom,and it is difficult to accurately describe the degree of its freedom.This paper takes RC as the research object,and the adjacency matrix is constructed based on topology and graph theory in order to describe the variation rule of topological configuration in the single layer rotation of RC.In this paper,the degree of freedom of the RC in any shape can be described by defining the concept of entanglement degree of freedom,establishing a set of adjacency matrix,and determining the degree of freedom of the RC which is attributed to the number of non⁃zero elements in the set of adjacent matrix.The prime number is proposed to describe the rotation of the RC combined with the rotation recognition of RC,which is simple and convenient for computer processing.The research contents in this paper are beneficial to the study of RC from the perspective of mechanism science.Meanwhile,it is of great significance to the study of other complex mechanisms with variable degrees of freedom. 展开更多
关键词 mechanism of Rubik􀆳s Cube topological configuration adjacency matrix degree of freedom prime number
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Application of integrated formation evaluation and three-dimensional modeling in shale gas prospect identification
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作者 Jin Gao Zhe Cao +3 位作者 Guangdi Liu Longmei Zhao Lijun Du Yuhua Kong 《Journal of Geological Research》 2019年第3期28-39,共12页
Identifying the shale gas prospect is crucial for gas extraction from such reservoirs.Junggar Basin(in Northwest China)is widely considered to have high potential as a shale gas resource,and the Jurassic,the most sign... Identifying the shale gas prospect is crucial for gas extraction from such reservoirs.Junggar Basin(in Northwest China)is widely considered to have high potential as a shale gas resource,and the Jurassic,the most significant gas source strata,is considered as prospective for shale gas exploration and development.This study evaluated the Lower Jurassic Badaowan Formation shale gas potential combined with geochemical,geological,and well logging data,and built a three-dimensional(3D)model to exhibit favorable shale gas prospects.In addition,methane sorption capacity was tested for verifying the prospects.The Badaowan shale had an average total organic carbon(TOC)content of 1.30 wt.%and vitrinite reflectance(Ro)ranging from 0.47%to 0.81%with dominated type III organic matter(OM).X-ray diffraction(XRD)analyses showed that mineral composition of Badaowan shale was fairly homogeneous and dominated by clay and brittle minerals.67 wells were used to identify prospective shale intervals and to delineate the area of prospects.Consequently,three Badaowan shale gas prospects in the Junggar Basin were identified:the northwestern margin prospect,eastern Central Depression prospect and Wulungu Depression prospect.The middle interval of the northwestern margin prospect was considered to be the most favorable exploration target benefitted by wide distribution and high lateral continuity.Generally,methane sorption capacity of the Badaowan shale was comparable to that of the typical gas shales with similar TOC content,showing a feasible gas potential. 展开更多
关键词 Shale gas PROSPECT Prospective interval Badaowan Formation Junggar Basin
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Analysis of Variance for Three-Way Unbalanced Mixed Effects Interactive Model
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作者 Emmanuel W. Okereke Joy C. Nwabueze Stanislaus O. Obinyelu 《Open Journal of Statistics》 2020年第2期261-273,共13页
In the study, a method of solving ANOVA problems based on an unbalanced three-way mixed effects model with interaction for data when factors A and B are fixed, and factor C is random was presented, and the required EM... In the study, a method of solving ANOVA problems based on an unbalanced three-way mixed effects model with interaction for data when factors A and B are fixed, and factor C is random was presented, and the required EMS was derived. Under each of the appropriate null hypotheses, it was observed that none of the derived EMS was unbiased for the other. Unbiased estimators of the mean squares were determined to test hypotheses. With the unbiased estimators,?appropriate F-statistics as well as their corresponding pseudo-degrees of freedom were obtained. The theoretical results presented in the paper were?illustrated using a numerical example. 展开更多
关键词 EXPECTED Mean SQUARE (EMS) Pseudo-degree of FREEDOM UNBIASED ESTIMATE Hypotheses Multi-Factor Experiments
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Existence of Solutions for a Multi-point Boundary Value Problems with Three Dimension Kernal at Resonance
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作者 LIANG Ju-hua REN Li-shun ZHAO Zhi-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期138-143,共6页
在这份报纸,多点的边界价值为三份订单的问题非线性的恭敬方程被考虑。在巧合定理的帮助下由于 Mawhin,一条存在定理被获得。
关键词 边界价值问题 巧合度定理 存在定理
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Generation of continuous-variable high-dimensional entanglement with three degrees of freedom and multiplexing quantum dense coding:publisher's note
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作者 Hui Guo Na Liu +4 位作者 Zhi Li Rongguo Yang Hengxin Sun Kui Liu Jiangrui Gao 《Photonics Research》 SCIE EI CAS CSCD 2023年第3期392-392,共1页
This publisher's note corrects the authorship in Photon.Res.10,2828(2022).
关键词 quantum CONTINUOUS degreeS
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