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Effective migration system of coalbed methane reservoirs in the southern Qinshui Basin

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Science China Earth Sciences 2014年第12期57卷 2978-2984页

作者： WU Caifang QIN yong ZHOU LongGang School of Resource and Earth Sciences China University of Mining & Technology Key Laboratory of CBM Resource and formation History Ministry of Education

Effective migration system of coalbed methane(CBM)reservoir,which was controlled by development degree and opening-closing degree of fractures,determines the permeability of coal reservoir and can be characterized by the pore-fracture system in the extrinsic *** this paper,based on coal matrix elastic self-regulating effect theory and coal reservoir combined elastic energy theory,the fracture opening-closing degree parameterΔand the fracture development degree parameterξare suggested for the quantitative study of the effective migration system of CBM reservoir in southern Qinshui ***,the control functions ofξandΔto CBM enrichment and high production are *** results show that in present stage the area with highξvalue is located in Anze and Qinyuan,and then Zhengzhuang and fangzhuang,where fracture development degree is *** area with highΔvalue is located in Zhengzhuang and fanzhuang,and then Anze and Qinyuan,indicating where coal matrix elastic self-regulating positive effect dominates and fractures tend to be *** the comprehensive analysis onξandΔ,it can be found that their best match area is located in Zhengzhuang and fanzhuang,with high values for fracture development degree and opening-closing degree probably bringing about high fluid pressure and good permeability of reservoirs,which are advantageous to an abundant CBM production.

关键词： CBM reservoirs effective migration system opening-closing degree of fracture development degree of fracture permeability

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Urban forestry and its Relevance to Tourism Development in Sabah

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Chinese forestry Science and Technology 2005年第1期4卷 27-34页

作者： LEE y f LIGUNJANG J yong S C forestry Department Sabah MalaysiaForestry Department Sabah MalaysiaForestry Department Sabah Malaysia

Urban forestry is understood to be the management of trees and forests in urban areas. It yieldsmany environmental and material benefits. In Sabah, the environmental services of urban forestry are moreimportant than material products. The potential of practising urban forestry in various zones and underdifferent land ownership is evaluated. As urbanisation has occurred recently in Sabah, urban forestry hasonly been practised to a limited extent. Tourism is an economic sector which has gained prominence in recentyears and has huge growth potential. With the numerous environmental services provided by urban forestryto make urban areas more inhabitable, the increasing tourism activities necessitate intensification of urbanforestry activities. The main urban centres contain many tourist attractions, and are also the gateways tomany other ecotourist destinations located throughout Sabah. With tourism high on the development agendain Sabah, urban forestry needs to be promoted so that both locals and visitors can enjoy the numerous social,environmental and economic benefits.

关键词： urban forestry tourism recreation wildlife conservation Sabah Malaysia

A dimeric structure of PD-L1: functional units or evolutionary relics?

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Protein & Cell 2010年第2期1卷 153-160页

作者： yong Chen Peipei Liu feng Gao Hao Cheng Jianxun Qi George f.Gao CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CASPMI)Beijing 100101China College of Life Sciences Graduate UniversityChinese Academy of SciencesBeijing 100049China Institute of Biophysics Chinese Academy of SciencesBeijing 100101China China-Japan Joint Laboratory of Molecular Immunology and Molecular Microbiology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China

PD-L1 is a member of the B7 protein family,most of whose members so far were identified as dimers in a solution and crystalline state,either complexed or uncomplexed with their ligand(s).The binding of PD-L1 with its receptor PD-1(CD279)delivers an inhibitory signal regulating the T cell *** with the Garboczi group,we successfully solved another structure of human PD-L1(hPD-L1).Our protein crystallized in the space group of C222_(1) with two hPD-L1 molecules per asymmetric *** comparison of reported B7 structures,we have found some intrinsic factors involved in the interaction of these two *** on these results,we tend to believe this uncomplexed hPD-L1 structure demonstrated its potential dimeric state in solution,althougt it could just be an evolutionary relic,too weak to be detected under present technology,or still a functional unit deserved our attentions.

关键词： PD-L1 crystal structure dimer costimulatory molecules B7 family

Analysis on crossover probability estimation using LDPC syndrome

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Science China(Information Sciences) 2011年第9期54卷 1895-1904页

作者： fANG yong College of Information Engineering,Northwest A&f University,yangling 712100,China College of Information Engineering Northwest A&F University Yangling China

Correlation estimation is a critical issue that impacts the application of Slepian-Wolf coding (SWC) in *** online correlation estimation is a type of newly-appearing approaches,in which the decoder estimates the virtual correlation channel between two correlated sources using both side information and the compressed SWC bitstream of the *** the compressed SWC bitstream usually contains partial information of the source,the emergence of dynamic online correlation estimation is helpful to solving the problem of correlation estimation in the SWC and further makes the SWC ***,the SWC is usually implemented by LDPC *** this case,the SWC bitstream is just the LDPC syndrome of the *** has been revealed that there are residual redundancies in LDPC syndromes,which can be used to estimate the crossover probability between two correlated binary ***,this algorithm has not been well justified *** paper makes use of the central limit theorem (CLT) to establish a mathematic model for analyzing the performance of this ***,for irregular LDPC codes,the optimization of weight vectors is discussed in *** experimental results are provided to validate the analysis.

关键词： distributed source coding Slepian-Wolf coding LDPC syndrome correlation estimation

Responses of breeding waterbird communities to environmental changes in subsidence wetlands in the North China Plain

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Avian Research 2023年第3期14卷 336-344页

作者： Guangyao Wang Jinming Zhao Weiqiang Li Xiangrong Song yong Zhang Chunlin Li Willem f.de Boer School of Resources and Environmental Engineering Anhui UniversityHefei230601China School of Life Science Huaibei Normal UniversityHuaibei235000China College of Biology and the Environment Nanjing Forestry UniversityNanjing210037China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration Anhui UniversityHefei230601China Wildlife Ecology and Conservation Group Wageningen University&Research6708PBWageningenthe Netherlands

In the context of global degradation and loss of natural wetlands,waterbirds have been increasingly using artificial wetlands as alternative ***,waterbirds are facing various threats in these artificial wetlands,due to dramatic environmental changes induced by anthropogenic *** the effects of these changes on the temporal dynamics of the waterbird communities can help understand how waterbirds adapt to environmental changes and thus formulate effective management and conservation *** this study,we carried out field surveys on waterbirds and environmental factors across 20 subsidence wetlands created by underground coal mining in the Huainan coal mining area in the breeding seasons of 2016 and *** predicted that the waterbird assemblages(i.e.,number of individuals,species richness,Shannon-Wiener diversity,Pielou evenness and species composition) differed between the two years,and that these differences were correlated with the temporal changes in environmental *** the surveyed wetlands,we recorded 26 waterbird species in 2016 and 23 in *** individual wetlands,the number of waterbird individuals and species richness increased by 71.6% and 20.1%,respectively,over the five years,with no changes in Shannon-Wiener diversity and Pielou *** overall increase in the number of bird individuals was mainly caused by an increase in vegetation gleaners and gulls that adapt well to anthropogenic *** species composition was significantly different between the two years,which was mainly caused by changes in the number of individuals of dominant species under influence of changes in human *** most wetlands,the temporal pairwiseβ-diversities could be explained by species turnover rather than nestedness,probably due to high mobility of waterbird species and dramatic changes in local *** study suggests that waterbird communities could respond to environmental changes in subsidence wetlands,

关键词： Artificial wetlands Environmental changes Subsidence wetlands Waterbird community

Existence and multiplicity of positive solutions for an elastic beam equation

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Applied Mathematics(A Journal of Chinese Universities) 2011年第3期26卷 253-264页

作者： SUN yong-ping College of Electron and Information Zhejiang University of Media and Communications Hangzhou310018 China.

This paper investigates the boundary value problem for elastic beam equation of the formu″″（t） q（t）f（t, u（t）,u′（t）,u″（t）,u′″（t））, 0〈t〈1,with the boundary conditionsu=（0）=u′（1）=u″（0）=u′″（1）=0.The boundary conditions describe the deformation of an elastic beam simply supported at left and clamped at right by sliding clamps. By using Leray-Schauder nonlinear alternate, Leray-Schauder fixed point theorem and a fixed point theorem due to Avery and Peterson, we establish some results on the existence and multiplicity of positive solutions to the boundary value problem. Our results extend and improve some recent work in the literature.

关键词： Positive solution existence and multiplicity elastic beam equation fixed point theorem nonlinear alternate.

Monotone positive solution for three-point boundary value problem

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Applied Mathematics(A Journal of Chinese Universities) 2008年第3期23卷 279-285页

作者： SUN yong-ping College of Electronics and Information Zhejiang University of Media and Communications Hangzhou310018 China

In this paper, the existence of monotone positive solution for the following secondorder three-point boundary value problem is studied：x″（t）＋f（t,x（t））=0,0〈t〈1,x′（0）=0,x（1）＋δx′（η）=0,where η ∈ （0, 1）, δ∈ [0, ∞）, f ∈ C（[0, 1] × [0, ∞）, [0, ∞））. Under certain growth conditions on the nonlinear term f and by using a fixed point theorem of cone expansion and compression of functional type due to Avery, Anderson and Krueger, sufficient conditions for the existence of monotone positive solution are obtained and the bounds of solution are given. At last, an example is given to illustrate the result of the paper.

关键词： three-point boundary value problem fixed point theorem monotone positive solution

Three Symmetric Positive Solutions for Second-order Nonlocal Boundary Value Problems

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 233-242页

作者： yong-ping Sun College of Electron and Information Zhejiang University of Media and Communications Hangzhou 310018China

Using the Leggett-Williams fixed point theorem, we will obtain at least three symmetric positive solutions to the second-order nonlocal boundary value problem of the form u″（t）＋g（t）f（t,u（t））=0,0〈t〈1,u（0）=u（1）=∫01m（s）u（s）ds. where m ∈ L1[0 1], g ：（0, 1）→ [0, ∞） is continuous, symmetric on （0, 1） and maybe singular at t = 0 and t = 1, f： [0, 1] × [0, ∞） → [0, ∞） is continuous and f（-, x） is symmetric on [0, 1] for all x∈ [0, ∞）.

关键词： symmetric positive solution nonlocal boundary value problem fixed point theorem

Existence and iteration of monotone positive solutions for a third-order two-point boundary value problem

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Applied Mathematics(A Journal of Chinese Universities) 2008年第4期23卷 413-419页

作者： SUN yong-ping School of Electronics and Information Zhejiang University of Media and Communications Hangzhou 310018 China

The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″（t）＋ q（t）f（t,u（t）,u′（t）） = 0, 0 〈 t 〈 1, u（0） = u″（0） = u′（1） = 0 is studied.... 详细信息

关键词： third-order two-point boundary value problem monotone iterative method positive solution,existence iterative scheme