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Implication of community-level ecophysiological parameterization to modelling ecosystem productivity:a case study across nine contrasting forest sites in eastern China 被引量:1
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作者 Minzhe Fang Changjin Cheng +2 位作者 Nianpeng He Guoxin Si Osbert Jianxin Sun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期1-11,共11页
Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations... Parameterization is a critical step in modelling ecosystem dynamics.However,assigning parameter values can be a technical challenge for structurally complex natural plant communities;uncertainties in model simulations often arise from inappropriate model parameterization.Here we compared five methods for defining community-level specific leaf area(SLA)and leaf C:N across nine contrasting forest sites along the North-South Transect of Eastern China,including biomass-weighted average for the entire plant community(AP_BW)and four simplified selective sampling(biomass-weighted average over five dominant tree species[5DT_BW],basal area weighted average over five dominant tree species[5DT_AW],biomass-weighted average over all tree species[AT_BW]and basal area weighted average over all tree species[AT_AW]).We found that the default values for SLA and leaf C:N embedded in the Biome-BGC v4.2 were higher than the five computational methods produced across the nine sites,with deviations ranging from 28.0 to 73.3%.In addition,there were only slight deviations(<10%)between the whole plant community sampling(AP_BW)predicted NPP and the four simplified selective sampling methods,and no significant difference between the predictions of AT_BW and AP_BW except the Shennongjia site.The findings in this study highlights the critical importance of computational strategies for community-level parameterization in ecosystem process modelling,and will support the choice of parameterization methods. 展开更多
关键词 BIOME-BGC community traits Forest Ecosystems model parameterization
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Community Climate Model 3模拟夏季极端降水的初步分析 被引量:15
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作者 黄丹青 钱永甫 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第3期238-248,共11页
采用累积频率的统计方法和Community Climate Model 3(CCM3)模拟的10年逐日降水结果,分析了模拟的夏季极端降水事件的时空分布特征.结果表明,CCM3模拟的极端降水阈值的大值区主要在我国黄河和长江流域的上游、印度半岛及其邻近海域和孟... 采用累积频率的统计方法和Community Climate Model 3(CCM3)模拟的10年逐日降水结果,分析了模拟的夏季极端降水事件的时空分布特征.结果表明,CCM3模拟的极端降水阈值的大值区主要在我国黄河和长江流域的上游、印度半岛及其邻近海域和孟加拉湾及其北部地区.CCM3能够模拟出我国长江流域极端降水量与极端降水日数显著增加的趋势.对极端降水平均强度、降水日数以及极端降水量与总降水量比值的经验正交函数(EOF)分析可知,我国大部分地区的极端降水基本呈现同相变化,且以长江和黄河中游地区较为显著.CCM3模式基本能够模拟出观测到的极端降水阈值与总降水、极端降水日数及其距平的高空间相关性. 展开更多
关键词 community CLIMATE model 3(CCM3) 数值模拟 累积频率 夏季极端降水 趋势 经验正交函数(EOF)分析 相关分析
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Global Climate Internal Variability in a 2000-year Control Simulation with Community Earth System Model(CESM) 被引量:13
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作者 WANG Zhiyuan LI Yao +1 位作者 LIU Bin LIU Jian 《Chinese Geographical Science》 SCIE CSCD 2015年第3期263-273,共11页
Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation ... Using the low-resolution (T31, equivalent to 3.75°× 3.75°) version of the Community Earth System Model (CESM) from the National Center for Atmospheric Research (NCAR), a global climate simulation was carried out with fixed external forcing factors (1850 Common Era. (C.E.) conditions) for the past 2000 years. Based on the simulated results, spatio-temporal structures of surface air temperature, precipitation and internal variability, such as the E1 Nifio-Southem Oscillation (ENSO), the Atlantic Multi-decadal Oscilla- tion (AMO), the Pacific Decadal Oscillation (PDO), and the North Atlantic Oscillation (NAO), were compared with reanalysis datasets to evaluate the model performance. The results are as follows: 1) CESM showed a good performance in the long-term simulation and no significant climate drift over the past 2000 years; 2) climatological patterns of global and regional climate changes simulated by the CESM were reasonable compared with the reanalysis datasets; and 3) the CESM simulated internal natural variability of the climate system performs very well. The model not only reproduced the periodicity of ENSO, AMO and PDO events but also the 3-8 years vari- ability of the ENSO. The spatial distribution of the CESM-simulated NAO was also similar to the observed. However, because of weaker total irradiation and greenhouse gas concentration forcing in the simulation than the present, the model performances had some differences from the observations. Generally, the CESM showed a good performance in simulating the global climate and internal natu- ral variability of the climate system. This paves the way for other forced climate simulations for the past 2000 years by using the CESM. 展开更多
关键词 community Earth System model (CESM) climate simulation past 2000 years climate system intemal variability
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Species abundance distribution models of Toona ciliata communities in Hubei Province,China 被引量:4
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作者 Yang Wang Huoming Zhou +2 位作者 Jingyong Cai Congwen Song Linzhao Shi 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期103-117,共15页
The study of plant species abundance distribution(SAD)in natural communities is of considerable importance to understand the processes and ecological rules of community assembly.With the distribution of tree,shrub and... The study of plant species abundance distribution(SAD)in natural communities is of considerable importance to understand the processes and ecological rules of community assembly.With the distribution of tree,shrub and herb layers of eight natural communities of Toona ciliata as research targets,three diff erent ecological niche models were used:broken stick model,overlapping niche model and niche preemption model,as well as three statistical models:log-series distribution model,log-normal distribution model and Weibull distribution model,to fi t SAD of the diff erent vegetation layers based on data collected.Goodness-of-fi t was compared with Chi square test,Kolmogorov–Smirnov(K–S)test and Akaike Information Criterion(AIC).The results show:(1)based on the criteria of the lowest AIC value,Chi square value and K–S value with no signifi cant diff erence(p>0.05)between theoretic and observed SADs.The suitability and goodness-of-fi t of the broken stick model was the best of three ecological niche models.The log-series distribution model did not accept the fi tted results of most vegetation layers and had the lowest goodness-of-fi t.The Weibull distribution model had the best goodness-of-fi t for SADs.Overall,the statistical SADs performed better than the ecological ones.(2)T.ciliata was the dominant species in all the communities;species richness and diversity of herbs were the highest of the vegetation layers,while the diversities of the tree layers were slightly higher than the shrub layers;there were fewer common species and more rare species in the eight communities.The herb layers had the highest community evenness,followed by the shrub and the tree layers.Due to the complexity and habitat diversity of the diff erent T.ciliata communities,comprehensive analyses of a variety of SADs and tests for optimal models together with management,are practical steps to enhance understanding of ecological processes and mechanisms of T.ciliata communities,to detect disturbances,and to facilitate biodiversity and species conservation. 展开更多
关键词 Toona ciliata community Tree-shrubherb layers Niche models Statistical models Species abundance distribution(SAD) model fi t
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A model of community capacity building for sustainable dengue problem solution in Southern Thailand 被引量:2
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作者 Charuai Suwanbamrung Anan Dumpan +2 位作者 Suwich Thammapalo Ratana Sumrongtong Pitaya Phedkeang 《Health》 2011年第9期584-601,共18页
Dengue community capacity (DCC) is important for developing a sustainable approach to over-coming the problem of dengue. The objectives were 1) to develop and 2) evaluate a dengue community capacity building model for... Dengue community capacity (DCC) is important for developing a sustainable approach to over-coming the problem of dengue. The objectives were 1) to develop and 2) evaluate a dengue community capacity building model for the leader and non-leader group in three communities selected by purposive technique. A mixed method research design was used employing both qualitative and quantitative methods with qualitative studies conducted for community capacity building model: assessment, planning, implementation, and evaluation. DCC level was assessed by the Dengue Community Capacity Assessment Tool (DCCAT) including larval indices, and morbidity and mortality rate. To analyze the differences of the leader and non-leader’s DCC levels both pre and post-interventions in each model, the Mann-Whitney and Independent T-test were used and to analyze the difference of the DCC level among the three models (Ban Mon, Ban Nangpraya and Ban Kang), the Kruskal-Wallis Test, ANOVA, and ANCOVA were used. The findings showed that there were some differences among the three models in dengue community capacity building in terms model. The participants consisted of leader (n = 26, 24 and 28) and non-leader groups (n = 200, 215 and 176 respectively). The DCC levels of both leader and non-leader groups increased post-intervention in each model (p < 0.001) and in all three models, showing a statistically significant difference between pre and post-intervention (p < 0.001). Ban Kang model demonstrated the highest DCC levels of leader and non-leader groups, the lowest larval indices (HI, BI, and CI), and no dengue morbidity. In contrast, Ban Mon and Ban Nangpraya model showed low DCC level in both leader and non-leader groups, a high rate of larval indices and high dengue morbidity rate. However, there was no mortality rate in three areas. The conclusion indicates that the model with a high DCC level showed low risk on the dengue index both entomological and epidemiology index. The model of dengue community capacity building for dengue solution was sustainability not only needs to be maintained DCC levels but also increased dependent upon the contexts of each community. 展开更多
关键词 DENGUE PROBLEM SOLUTION model community Capacity BUILDING SUSTAINABLE Thailand
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Evaluation of the Community Microwave Emission Model Coupled with the Community Land Model over East Asia 被引量:1
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作者 JIA Bing-Hao XIE Zheng-Hui 《Atmospheric and Oceanic Science Letters》 2011年第4期209-215,共7页
The Community Microwave Emission Model (CMEM) developed by the European Centre for Me-dium-Range Weather Forecasts (ECMWF) can provide a link between surface states and satellite observations and simulate the passive ... The Community Microwave Emission Model (CMEM) developed by the European Centre for Me-dium-Range Weather Forecasts (ECMWF) can provide a link between surface states and satellite observations and simulate the passive microwave brightness temperature of the surface at low frequencies (from 1 GHz to 20 GHz).This study evaluated the performance of the CMEM cou-pled with the Community Land Model (CLM) (CMEM-CLM) using C-band (6.9 GHz) microwave brightness temperatures from the Advanced Microwave Scanning Radiometer on Earth Observing System (AMSR-E) over East Asia.Preliminary results support the argument that the simulated brightness temperatures of CMEM-CLM from July 2005 to June 2010 are comparable to AMSR-E observational data.CMEM-CLM performed better for vertical polarization,for which the root mean square error was approximately 15 K,compared to over 30 K for horizontal polarization.An evaluation performed over seven sub-regions in China indicated that CMEM-CLM was able to capture the temporal evolution of C-band brightness temperatures well,and the best correlation with AMSR-E appeared over western Northwest China (over 0.9 for vertical polarization).However,larger biases were found over southern North China and the middle and lower reaches of the Yangtze River. 展开更多
关键词 community Microwave Emission model community Land model microwave brightness temperature AMSR-E
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Density-based rough set model for hesitant node clustering in overlapping community detection 被引量:2
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作者 Jun Wang Jiaxu Peng Ou Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1089-1097,共9页
Overlapping community detection in a network is a challenging issue which attracts lots of attention in recent years.A notion of hesitant node(HN) is proposed. An HN contacts with multiple communities while the comm... Overlapping community detection in a network is a challenging issue which attracts lots of attention in recent years.A notion of hesitant node(HN) is proposed. An HN contacts with multiple communities while the communications are not strong or even accidental, thus the HN holds an implicit community structure.However, HNs are not rare in the real world network. It is important to identify them because they can be efficient hubs which form the overlapping portions of communities or simple attached nodes to some communities. Current approaches have difficulties in identifying and clustering HNs. A density-based rough set model(DBRSM) is proposed by combining the virtue of densitybased algorithms and rough set models. It incorporates the macro perspective of the community structure of the whole network and the micro perspective of the local information held by HNs, which would facilitate the further "growth" of HNs in community. We offer a theoretical support for this model from the point of strength of the trust path. The experiments on the real-world and synthetic datasets show the practical significance of analyzing and clustering the HNs based on DBRSM. Besides, the clustering based on DBRSM promotes the modularity optimization. 展开更多
关键词 density-based rough set model(DBRSM) overlapping community detection rough set hesitant node(HN) trust path
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Community effects on public health in India: A hierarchical model 被引量:1
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作者 Sada Nand Dwivedi Shahina Begum +1 位作者 Alok Kumar Dwived Arvind Pandey 《Health》 2012年第8期526-536,共11页
The data on any aspect of public health, including that on infant mortality, has inbuilt hierarchical structure. Using traditional regression approach in data analysis, i.e., ignoring hierarchical structure, either at... The data on any aspect of public health, including that on infant mortality, has inbuilt hierarchical structure. Using traditional regression approach in data analysis, i.e., ignoring hierarchical structure, either at micro (individual) or at macro (community) level will be avoiding desired assumption related to independence of records. Accordingly, this may result into distortion in the results due to probable underestimation of standard error of the regression coefficients. To be more specific, an irrelevant co-variate may emerge as an important covariate leading to inappropriate public health implications. To overcome this problem, the objective of the present work was to deal with multilevel analysis of the data on infant mortality available under second round of National family Health Survey and notify changes in results under traditional regression analysis that ignores hierarchical structure of data. This method provides more accurate results leading to meaningful public health implications. In addition, estimation of variability at different levels and their covariance are also obtained. The results indicate that the community (e.g., state) level characteristics still have major role regarding infant mortality in India. Further, if computational facilities are available, multilevel analysis may be preferred in dealing with data involving hierarchical structure leading to accurate results having meaningful public health implications. 展开更多
关键词 community Effects PUBLIC Health MULTILEVEL Analysis Hierarchical model TRADITIONAL Regression model
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Sharing and evaluation of a new community co-management model for protecting Crested Ibis:a case study of Crested Ibis National Nature Reserve,China 被引量:5
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作者 WANG Chang-hai WEN Ya-li +2 位作者 LIU Xiao-hai KANG Kai-li LI Bing 《Ecological Economy》 2010年第4期376-386,共11页
The Crested Ibis(Nipponia Nippon) is endemic to Qinling Mountains of China and was once abundant over vast areas of north-east of Asia habitat.During the 20th century,however,the population declined greatly in numbers... The Crested Ibis(Nipponia Nippon) is endemic to Qinling Mountains of China and was once abundant over vast areas of north-east of Asia habitat.During the 20th century,however,the population declined greatly in numbers.Habitat quality used to be the main threat to this species but recent actions by the government and wildlife protection organizations have brought this under control.With the establishment of Crested Ibis Nature Reserve in China,conflicts between socio-economic development and Crested Ibis conservation have become more acute.How do we deal with the relation between Crested Ibis conservation and community development? In this study,the Crested Ibis Nature Reserve co-management model namely "companies + farmers + Nature Reserve" model is proposed and evaluated with demonstration investigation methods,including continuous six-year fixed-site socio-economic development data of surrounding community,company sales revenue data and monitored data of Crested Ibis Nature Reserve.The results show that farmers' income and conservation awareness increased greatly from 2003 to 2008;company sales revenue has increased by about 20% annually in the recent years;management level has noticeably improved in Nature Reserve,the scope of Crested Ibis habitat has expanded 50 hm2;chemical composition of habitat reduced year after year;and the number of Crested Ibis had been growing annually.At the end,the success of the model is evaluated,and problems in implementation of the model are discussed from the following aspects:management system,co-management concept,economic base of partners,marketing mechanism,technical capacity and so on. 展开更多
关键词 SHARING EVALUATION community co-management Crested Ibis Crested Ibis National Nature Reserve model Marketing mechanism
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A Multi-case Study of Community Supported Agriculture (CSA) Operation Model in Beijing 被引量:1
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作者 CHEN Yingying 《Journal of Landscape Research》 2021年第4期89-93,99,共6页
As one of the ways to localize foods,community supported agriculture can strengthen food safety and should be reasonably guided and developed.Based on the analysis of the spatial layout of the community supported agri... As one of the ways to localize foods,community supported agriculture can strengthen food safety and should be reasonably guided and developed.Based on the analysis of the spatial layout of the community supported agriculture organizations in Beijing,this paper described the development framework and course of community supported agriculture in Beijing.Combining 3 differentiated cases with the consumer's participation in community supported agriculture and the trust mechanism,it was found that the drive type has a very significant impact on the characteristics of these organizations. 展开更多
关键词 community Supported Agriculture Operation model Consumer participation Trust mechanism Consumer-driven Producer-driven
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Spatio-Temporal Variations in Co-Occurrence Patterns of Fish Communities in Haizhou Bay, China: Null Model Analysis
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作者 WANG Jiao ZHANG Chongliang +3 位作者 XUE Ying CHEN Yong REN Yiping XU Binduo 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第6期1497-1506,共10页
Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patte... Co-occurrence pattern of fish species plays an important role in understanding the spatio-temporal structure and the stability of fish community.Species coexistence may vary with time and space.The co-occurrence patterns of fish species were examined using the C-score under fixed-fixed null model for fish communities in spring and autumn over different years in the Haizhou Bay,China.The results showed that fish assemblages in the whole bay had non-random patterns in spring and autumn over different years.However,the fish co-occurrence patterns were different for the northern and southern fish assemblages in spring and autumn.The northern fish assemblage showed structured pattern,whereas the southern assemblage were randomly assembled in spring.The co-occurrence patterns of fish communities were relatively stable over different years,and the number of significant species pairs in northern assemblage was more than that in the southern assemblage.Environmental heterogeneity played an important role in determining the distributions of fish species that formed significant species pairs,which might affect the co-occurrence patterns of northern and southern assemblages further in the Haizhou Bay. 展开更多
关键词 FISH community Haizhou BAY NULL model analysis SPECIES CO-OCCURRENCE pattern
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Community detection in signed networks based on discrete-time model
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作者 Jianrui Chen Li Zhang +1 位作者 Weiwei Liu Zaizai Yan 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期574-583,共10页
Community detection in signed networks has been studied widely in recent years. In this paper, a discrete difference equation is proposed to imitate the consistently changing phases of the nodes. During the interactio... Community detection in signed networks has been studied widely in recent years. In this paper, a discrete difference equation is proposed to imitate the consistently changing phases of the nodes. During the interaction, each node will update its phase based on the difference equation. Each node has many different nodes connected with it, and these neighbors have different influences on it. The similarity between two nodes is applied to describe the influences between them. Nodes with high positive similarities will get together and nodes with negative similarities will be far away from each other.Communities are detected ultimately when the phases of the nodes are stable. Experiments on real world and synthetic signed networks show the efficiency of detection performance. Moreover, the presented method gains better detection performance than two existing good algorithms. 展开更多
关键词 community detection signed networks discrete-time model SIMILARITY
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Continuance intention to use the mobile interest-based community: An integrated theoretical model and empirical study 被引量:1
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作者 Jiming HU Jing YU 《Chinese Journal of Library and Information Science》 2015年第2期52-68,共17页
Purpose: This paper aims at an understanding of factors that influence the continuance intention to use mobile interest-based community applications, with a focus on the impacts of technology acceptance model (TAM)... Purpose: This paper aims at an understanding of factors that influence the continuance intention to use mobile interest-based community applications, with a focus on the impacts of technology acceptance model (TAM) constructs and experiential value. Design/methodology/approach: Taking a hybrid model combining TAM and extended expectation confirmation model (ECM) as foundation, this study integrated experiential value into the research model. A survey method was adopted and the sample was constituted by 347 Chinese undergraduates who were experienced users of mobile interest-based community applications. Structural equation modeling was used to test the research model. Findings: Our findings suggest that 1) key determinants of user satisfaction with mobile interest-based community applications are confirmation, perceived usefulness (PU), perceived ease of use (PEU) and experiential value. Both satisfaction and PU are directly correlated with continuance intention; 2) PU's impact on satisfaction and continuance intention has been confirmed again in this study. Although PEU has no direct impact on satisfaction and continuance intention, it may indirectly affect them via PU; 3) all the perceived experiential values (aesthetics, playfulness, service excellence and return on investment) have a positive influence on satisfaction. Research limitations: We did not examine the effects of individual user differences that may also be important for understanding satisfaction and continuance intention. Practical implications: The study findings can help service providers improve the use of mobile interest-based community applications. Originality/value: Our study contributes to a more systematic understanding of factors that influence continuous use of mobile interest-based community applications. 展开更多
关键词 Mobile interest-based community Continuance intention Expectationconfirmation model (ECM) Experiential value
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A thermal flux-diffusing model for complex networks and its applications in community structure detection
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作者 沈毅 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期637-643,共7页
We introduce a thermal flux-diffusing model for complex networks. Based on this model, we propose a physical method to detect the communities in the complex networks. The method allows us to obtain the temperature dis... We introduce a thermal flux-diffusing model for complex networks. Based on this model, we propose a physical method to detect the communities in the complex networks. The method allows us to obtain the temperature distribution of nodes in time that scales linearly with the network size. Then, the local community enclosing a given node can be easily detected for the reason that the dense connections in the local communities lead to the temperatures of nodes in the same community being close to each other. The community structure of a network can be recursively detected by randomly choosing the nodes outside the detected local communities. In the experiments, we apply our method to a set of benchmarking networks with known pre-determined community structures. The experiment results show that our method has higher accuracy and precision than most existing globe methods and is better than the other existing local methods in the selection of the initial node. Finally. several real-world networks are investigated. 展开更多
关键词 complex networks community structure thermal flux-diffusing model
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Origin and advances in implementing blowing-snow effects in the Community Land Model
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作者 ZeYong Hu ZhiPeng Xie 《Research in Cold and Arid Regions》 CSCD 2019年第5期335-339,共5页
Snow cover on the Tibetan Plateau(TP)is closely related to regional and continental biological and hydrological processes.The vast snow cover,special climatic conditions,and sparse vegetative cover over the TP facilit... Snow cover on the Tibetan Plateau(TP)is closely related to regional and continental biological and hydrological processes.The vast snow cover,special climatic conditions,and sparse vegetative cover over the TP facilitate the occurrence of blowing snow,leading to substantial heterogeneities in the snow cover and great promotion in the moisture supply from the land surface to the overlying atmospheric boundary layer.However,blowing-snow processes are significantly misrepresented or even neglected in current models,which causes considerable uncertainties of numerical model simulations and leads to erroneous estimates of snow-related processes in mountainous terrain.We present in this paper a brief review of our work in the past 5 years to serve as a basis for further development and improvement of the land-surface model.These studies can be divided into three parts:detection of the problems,development of the land-surface model,and application of the coupled model over the TP(the logical framework is presented in Figure 1).The origin and advances in the development of a land-surface model with consideration of blowing-snow effects are described herein;and the importance of blowing-snow processes in the land-surface model,especially over the TP,is highlighted.We expect that the blowingsnow studies over the TP will play a key role in documenting and understanding the land-surface processes(LSPs)and the cryospheric changes over the TP. 展开更多
关键词 BLOWING SNOW LAND surface process community LAND model TIBETAN Plateau
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Impacts of Vegetation on the Intraseasonal Oscillation Simulated by the Community Atmosphere Model (CAM3)
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作者 HAN Ying XU Zhong-Feng 《Atmospheric and Oceanic Science Letters》 2011年第1期1-6,共6页
The influences of vegetation on intraseasonal oscillation (ISO) were examined using the Community Atmosphere Model version 3 (CAM3). Two 15-year numerical experiments were completed: the first was performed with ... The influences of vegetation on intraseasonal oscillation (ISO) were examined using the Community Atmosphere Model version 3 (CAM3). Two 15-year numerical experiments were completed: the first was performed with a realistic vegetation distribution (VEG run), and the second was identical to the VEG run except without land vegetation (NOVEG run). Generally speak- ing, CAM3 was able to reproduce the spatial distribution of the ISO, but the ISO intensity in the simulation was much weaker than that observed in nature: the 1SO has a relatively much stronger signal. A comparison of the VEG run with the NOVEG run revealed that the presence of vegetation usually produces a weak ISO. The vegetation effects on ISO intensity were significant over West Africa and South Asia, especially in the summer half-year. Vegetation also plays an important role in modulating ISO propagation. The eastward propagation of the ISO in the VEG run was clearer than that in the NOVEG run over the West African and Maritime Continent regions. The northward propagation of the ISO in the VEG run was more consistent with observation than that in the NOVEG run. 展开更多
关键词 VEGETATION intraseasonal oscillation ISO intensity ISO propagation community atmosphere model
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Bi-Level Energy Management Model of Grid-Connected Microgrid Community
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作者 Haibin Cao Houqi Dong +3 位作者 Yongjie Ren Yuqing Wang Na Li Ming Zeng 《Energy Engineering》 EI 2022年第3期965-984,共20页
As the proportion of renewable energy power generation continues to increase,the number of grid-connected microgrids is gradually increasing,and geographically adjacent microgrids can be interconnected to form a Micro... As the proportion of renewable energy power generation continues to increase,the number of grid-connected microgrids is gradually increasing,and geographically adjacent microgrids can be interconnected to form a Micro-Grid Community(MGC).In order to reduce the operation and maintenance costs of a single micro grid and reduce the adverse effects caused by unnecessary energy interaction between the micro grid and the main grid while improving the overall economic benefits of the micro grid community,this paper proposes a bi-level energy management model with the optimization goal of maximizing the social welfare of the micro grid community and minimizing the total electricity cost of a single micro grid.The lower-level model optimizes the output of each equipment unit in the system and the exchange power between the system and the external grid with the goal of minimizing the operating cost of each microgrid.The upper-level model optimizes the goal ofmaximizing the socialwelfare of themicrogrid.Taking amicrogrid community with four microgrids as an example,the simulation analysis shows that the proposed optimization model is beneficial to reduce the operating cost of a single microgrid,improve the overall revenue of the microgrid community,and reduce the power interaction pressure on the main grid. 展开更多
关键词 Renewable energy grid-connected micro-grid community bi-level energy management model
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Evaluation of Development Model of Community Residential Areas in a World Heritage Site:A Case Study of Wulingyuan Scenic Spot in Zhangjiajie
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作者 YAO Junjie YUAN Yuan 《Journal of Landscape Research》 2022年第1期104-106,111,共4页
In order to provide suggestions of development model for residential areas in the Wuling mountainous area with changes in the industrial model brought about by tourism development, the evaluation model of the developm... In order to provide suggestions of development model for residential areas in the Wuling mountainous area with changes in the industrial model brought about by tourism development, the evaluation model of the development modes of 8 local residential areas was constructed by using the ordering relation analysis method. It is concluded that Nanyuan Group belongs to relocation type;Shuijingya, Nanzhang, Miaota and Lijia groups are disentanglement type;Xiejia, Chazhang and Dengjia groups are control type. The study provides reference data for the community to balance the relationship between tourism development and traditional production and life, and has certain guiding significance for local community planning and development. 展开更多
关键词 Residential community protection Evaluation model Ordering relation analysis method
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Community health worker model for health care delivery and environment programs focused on initiatives in USA and India
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作者 Muskaan Chhibber Pranav Selvan +4 位作者 Gurvinder Singh Amartya Dave Akram Alnounou Sandeep Bajaj Melishia Bansa 《History & Philosophy of Medicine》 2021年第1期1-7,共7页
Community health workers are equipped with the tools and resources necessary to bring about a change in the form of a rapid chain reaction.The community health workers model focuses on the practices,strategies,plans,a... Community health workers are equipped with the tools and resources necessary to bring about a change in the form of a rapid chain reaction.The community health workers model focuses on the practices,strategies,plans,and implementation techniques needed to organize a community health event based on diverse agendas:health,environment,and minorities.This model encompasses past experiences as a guide with tested strategies to assist future health interns with a ground framework and resources to showcase the importance of adopting healthy and environmentally friendly practices.The basic outline of the model is based on data collected from various community health events in Illinois(United States of America)and New Delhi(India).These events included back to school fairs,cleanliness drives,health camps,and educational events.As community health workers can help in implementing better practices in the masses through one-on-one interactions,this model of community health worker programs would outline event organization tips,predicted outcomes,targeted audience,and required material templates.The next phase of this model highlights utilizing the data and experience from these events to report to the health ministries of different countries for the incorporation of the proposed practices in their health agendas and policies.This model,if implemented unanimously,could bring about a revolution in the arena of health workers.They will be assisted at each step,will establish connections with health workers globally,and share their health and environment-based agendas to collaborate and organize important events.This model envisions a strong established network of community health workers,display of their agenda,and creation of a ripple effect throughout the society by the means of these programs. 展开更多
关键词 CHW community health workers Health care Delivery PROGRAMS model
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Techno-Financial Analysis of Energy Access through Hybrid System with Solar PV under the Various Rural Community Models for State of Uttarakhand, India
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作者 Ashish Verma Saurabh Biswas Syed Yasir Ahmad 《Smart Grid and Renewable Energy》 2015年第4期75-94,共20页
Uttarakhand state comes under special category state where approximately 69.45% population lived in rural area under the population density with varied range of 37 to 607 persons per sq.km. Although Uttarakhand is hav... Uttarakhand state comes under special category state where approximately 69.45% population lived in rural area under the population density with varied range of 37 to 607 persons per sq.km. Although Uttarakhand is having per capita consumption of 1112.29 kWh which is higher than national average per capita consumption of 779 kWh as till date, but remote communities, villages are not able to access clean, cheep and good quality of energy due to uneven terrain, lack of proper transmission & distribution lines [1]. 100% villages are electrified under the RGGVY scheme as per the Ministry of Power Government of India, but due to poor loading of transformer, lack of grid infrastructure and natural calamities, remote house owners are not able to get good quality of power thus affect the livelihood and source of income generation in various means [2]. As Uttarakhand state having future plans to be make state energy sufficient and energy access to all by year 2016-2017, so major ground level initiative have been taken by Government of Uttarakhand. The government of Uttarakhand has incorporated innovative business model to provide good quality of power with non-conventional energy source. Under the initiative invlovement of local people and village level, panchayats have ownership and responsibility to operate these clean energy business model to improve livelihood in remote hilly places of Uttarakhand. Under this analysis, five different type of community models are categorized as Community 1, Community 2, Community 3, Standalone 1 & Standalone 2 for rural &remote communities based on number of unclustered households with the distance covered between 200 m to 20 km, and electrical loads i.e. lighting, fan, mobile chargers, television along with time of day energy consumption patterns. These community models are for remote hilly location where grid integration and distribution lines are not feasible to built due to hilly terrain, low soil strength and huge expenses for expanding power cables for supplying good quality power. The preliminary studies and simulations has been done in HOMER tool by considering the various composite source of power, i.e. Solar PV with battery bank, Solar PV with battery Bank & Generator, and Solar PV along with DG. These three hybrid source of power generation with Solar PV as base source under five different community models, the techno-commercial feasibility has been analyzed in terms of load sharing proposition with Solar PV and battery, DG, Energy production through PV, load consumption per year, Excess and unmet energy monitoring, battery sizing to meet the load during nights, DG operation when the solar energy not available due to weather condition and non availability of sunshine in night. Financial feasibility has been examined in terms of levelized cost of energy, cost summary and O&M cost per year of three integrated sources of energy generation with Solar PV under each community model. Solar PV power plant , which is the best renewable source of energy to cater energy access issue in remote hilly places. The Uttarakhand receives good amout of daily average radiation level of 5.14 - 5.50 kWh/m2/day. Financial feasible community models for different hilly region based on their energy consumption need to be implemented with the help of local community by providing ownership to local people, panchayat, for it not only caters energy access issue but also provides clean, cheep, uninterruptable energy and improves livelihood standard to locals by engaging them into operation maintenance and tariff or rent collection. The study shows that Solar PV power plant with battery bank is the optimal solution considering life cycle cost of hybrid system. It is feasible due to low operation and maintenance cost, price declination of battery and Solar PV module, battery prices at time of replacement. 展开更多
关键词 Distributed community modelS HOMER Hybrid Energy Solution Solar PV HILLY Region
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