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Integrating Neighborhood Geographic Distribution and Social Structure Influence for Social Media User Geolocation
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作者 Meng Zhang Xiangyang Luo Ningbo Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2513-2532,共20页
Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local conten... Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local content recommen-dations.Social relationship-based methods represent a classical approach for geolocating social media.However,geographically proximate relationships are sparse and challenging to discern within social networks,thereby affecting the accuracy of user geolocation.To address this challenge,we propose user geolocation methods that integrate neighborhood geographical distribution and social structure influence(NGSI)to improve geolocation accuracy.Firstly,we propose a method for evaluating the homophily of locations based on the k-order neighbor-hood geographic distribution(k-NGD)similarity among users.There are notable differences in the distribution of k-NGD similarity between location-proximate and non-location-proximate users.Exploiting this distinction,we filter out non-location-proximate social relationships to enhance location homophily in the social network.To better utilize the location-proximate relationships in social networks,we propose a graph neural network algorithm based on the social structure influence.The algorithm enables us to perform a weighted aggregation of the information of users’multi-hop neighborhood,thereby mitigating the over-smoothing problem of user features and improving user geolocation performance.Experimental results on real social media dataset demonstrate that the neighborhood geographical distribution similarity metric can effectively filter out non-location-proximate social relationships.Moreover,compared with 7 existing social relationship-based user positioning methods,our proposed method can achieve multi-granularity user geolocation and improve the accuracy by 4.84%to 13.28%. 展开更多
关键词 User geolocation social media neighborhood geographic distribution structure influence
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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen Collection preference Dominant plant species Environmental range geographical range Species traits
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Geographical Variation in the Advertisement Calls of Leptobrachella ventripunctata(Anura:Megophryidae)in Southwestern China
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作者 Chaobo FENG Tuo SHEN +4 位作者 Lang MU Jing LIU Shize LI Yixin DIAO Haijun SU 《Asian Herpetological Research》 SCIE CSCD 2024年第3期140-151,共12页
In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China... In anurans,advertisement calls(ACs)are an essential form of intraspecific communication.This study evaluates geographical variation in the ACs of Leptobrachella ventripunctata in the Guizhou Plateau,southwestern China,and explores correlations between call characteristics,body size,and environmental factors.ACs are simple calls of L.ventripunctata,and apparent differences were observed in the ACs among different geographical populations of L.ventripunctata.The Call duration(CD)revealed a significant positive correlation with altitude and a significant negative correlation with temperature and humidity.Moreover,the Dominant frequency(DF)exhibited a significant negative correlation with altitude and the habitat closure degree and a significant positive correlation with temperature.These variations in ACs between different geographical populations of L.ventripunctata may critically impact the adaptive evolution of species,and the calls may also be relevant for environmental selection. 展开更多
关键词 ANURAN BIOACOUSTICS environmental factors geographical divergence
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Geographically and Temporally Weighted Regression in Assessing Dengue Fever Spread Factors in Yunnan Border Regions
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作者 ZHU Xiao Xiang WANG Song Wang +3 位作者 LI Yan Fei ZHANG Ye Wu SU Xue Mei ZHAO Xiao Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期511-520,共10页
Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-tempor... Objective This study employs the Geographically and Temporally Weighted Regression(GTWR)model to assess the impact of meteorological elements and imported cases on dengue fever outbreaks,emphasizing the spatial-temporal variability of these factors in border regions.Methods We conducted a descriptive analysis of dengue fever’s temporal-spatial distribution in Yunnan border areas.Utilizing annual data from 2013 to 2019,with each county in the Yunnan border serving as a spatial unit,we constructed a GTWR model to investigate the determinants of dengue fever and their spatio-temporal heterogeneity in this region.Results The GTWR model,proving more effective than Ordinary Least Squares(OLS)analysis,identified significant spatial and temporal heterogeneity in factors influencing dengue fever’s spread along the Yunnan border.Notably,the GTWR model revealed a substantial variation in the relationship between indigenous dengue fever incidence,meteorological variables,and imported cases across different counties.Conclusion In the Yunnan border areas,local dengue incidence is affected by temperature,humidity,precipitation,wind speed,and imported cases,with these factors’influence exhibiting notable spatial and temporal variation. 展开更多
关键词 Dengue fever Meteorological factor geographically and temporally weighted regression
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Comprehensive Analysis of Gender Classification Accuracy across Varied Geographic Regions through the Application of Deep Learning Algorithms to Speech Signals
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作者 Abhishek Singhal Devendra Kumar Sharma 《Computer Systems Science & Engineering》 2024年第3期609-625,共17页
This article presents an exhaustive comparative investigation into the accuracy of gender identification across diverse geographical regions,employing a deep learning classification algorithm for speech signal analysi... This article presents an exhaustive comparative investigation into the accuracy of gender identification across diverse geographical regions,employing a deep learning classification algorithm for speech signal analysis.In this study,speech samples are categorized for both training and testing purposes based on their geographical origin.Category 1 comprises speech samples from speakers outside of India,whereas Category 2 comprises live-recorded speech samples from Indian speakers.Testing speech samples are likewise classified into four distinct sets,taking into consideration both geographical origin and the language spoken by the speakers.Significantly,the results indicate a noticeable difference in gender identification accuracy among speakers from different geographical areas.Indian speakers,utilizing 52 Hindi and 26 English phonemes in their speech,demonstrate a notably higher gender identification accuracy of 85.75%compared to those speakers who predominantly use 26 English phonemes in their conversations when the system is trained using speech samples from Indian speakers.The gender identification accuracy of the proposed model reaches 83.20%when the system is trained using speech samples from speakers outside of India.In the analysis of speech signals,Mel Frequency Cepstral Coefficients(MFCCs)serve as relevant features for the speech data.The deep learning classification algorithm utilized in this research is based on a Bidirectional Long Short-Term Memory(BiLSTM)architecture within a Recurrent Neural Network(RNN)model. 展开更多
关键词 Deep learning recurrent neural network voice signal mel frequency cepstral coefficients geographical area GENDER
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Cluster Analysis of Morphologic Characteristic of Eight Geographical Populations of Rana Dybowskii 被引量:1
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作者 应璐 徐艳春 +2 位作者 黄孝明 田秀华 汪青雄 《Agricultural Science & Technology》 CAS 2008年第1期104-106,110,共4页
[ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geogra... [ObJective] The research aimed to determine the geographic distribution map of system of Rana dybowskii. [Method] Four morphologic indices (body length, body weight, forelimb length, hindlimb length) of eight geographical populations of R.dybowskii which naturally distribute in Changhai Mountain and Xiaoxing'an Mountain were measured. Measure results were variance analyzed and cluster analyzed. [Result] Variance analysis showed: the genetic branching among the Dongfanghong male population( belongs to Wandashan) and Xiaoxing'an Mountain male population and Changbai Mountain male population were significantly different (P〈0.05) ; the genetic branching between the Hebei female population (belongs to Xiaoxing'an Mountain) and Changbai Mountain female population was significantly different (P〈0.05 ). Cluster analysis showed : male R.dybowskii can be divided into three groups : the first group included Quanyang, Tianbei, Chaoyang and Ddkouqin, the second group included Tieli and Anshan, the third group included Dongfanghong; and the female R. dybowskii can be divided into three groups : the first group included Quanyang and Chaoyang, the second group included Tianbei and Dakouqin, the third group included Hebei. [Condusion] The paper deduced that the Sanjiang Plain was the geographical origin center ofR. dybowskii which radiated to Changbai Mountain and Xiaoxing'an Mountain along the adverse current of Songhua River basin, therefore, the current distribution pattern of R. dybowskii was formed. 展开更多
关键词 Rana dybowskii geographical population Morphologic characteristic Distribution pattern geographical origin Cluster analysis
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Exploration of the spatial pattern of urban residential land use with geographically weighted regression technique: a case study of Nanjing,China 被引量:1
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作者 胡明星 吴江 朱选 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期149-156,共8页
As the traditional methods and technical means cannot meet the quantitative research needs of the urban land use patterns, quantitative research methods for the urban land use pattern are established via the GIS (geo... As the traditional methods and technical means cannot meet the quantitative research needs of the urban land use patterns, quantitative research methods for the urban land use pattern are established via the GIS (geographic information system ) technique combined with the related theories and models. Taking the city of Nanjing as an example, a spatial database of urban land use and other environmental and socio-economic data is constructed. A multiple linear regression model is developed to determine the statistically significant factors affecting the residential land use distributions. To explain the spatial variations of urban land use patterns, the geographically weighted regression (GWR) is employed to establish spatial associations between these significant factors and the distribution of urban residential land use. The results demonstrate that the GWR can provide an effective approach to the exploration of the urban land use spatial patterns and also provide useful spatial information for planning residential development and other types of urban land use. 展开更多
关键词 urban residential land use GIS geographic information system) multiple linear regression geographically weighted regression
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Geographic variation and provenance selection for bamboo wood properties in Bambusa chungii 被引量:3
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作者 杨秀艳 傅懋毅 +1 位作者 谢锦忠 李正才 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A3期261-267,287,共9页
Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed... Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed by the methods of Analysis of variance and correlation coefficient to reveal the geographic genetic variation situation. The results showed that there are significant differences between fiber length, fibrin and 1% NaOH extraction contents of B. chungii from 8 provenances; moreover, the fiber length and fiber length/width ratio had a decreasing change pattern with geographic variation from the south to the north in altitude (from high to low in elevation). The heritabilities for fibrin, fiber length, 1% NaOH extractive, lignin and fiber length/width ratio were 0.7, 0.84, 0.54, 0.38 and 0.13, respectively. A significant negative correlation was found between 1% NaOH extraction, benzo-alcohol extraction contents and bamboo culm yield, whereas there was a significant positive correlation between fibrin contents and bamboo wood yield. Besides, a close correlation was detected between fiber dimensions indices and bamboo growth or bamboo wood yield. Finally, three provenances with high qualities and culm yield, i.e. Huaiji, Xinyi and Guilin, were selected as superior sources based on principal component analysis. 展开更多
关键词 Bambusa chungii bamboo wood property pulp-bamboo geographic variation provenance selection
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Interspecific Transition Among Caragana microphylla, C. davazamcii and C. korshinskii Along Geographic Gradient. Ⅱ. Characteristics of Photosynthesis and Water Metabolism 被引量:13
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作者 马成仓 高玉葆 +1 位作者 郭宏宇 王金龙 《Acta Botanica Sinica》 CSCD 2003年第10期1228-1237,共10页
The characteristics of photosynthesis and water metabolism of Caragana microphylla Lam.,C. davazamcii Sancz. and C. korshinskii Kom. populations in different sites (117.6o-105.7o E, 44.6o-38.8o N)were studied. (1) Fro... The characteristics of photosynthesis and water metabolism of Caragana microphylla Lam.,C. davazamcii Sancz. and C. korshinskii Kom. populations in different sites (117.6o-105.7o E, 44.6o-38.8o N)were studied. (1) From the east to the west, the responses of the three species to photosyntheticallyavailable radiation (PAR) in net photosynthesis rate increased, the relative humidity of the air whichcorresponded to the occurrence of maximum photosynthesis rate decreased, and the corresponding airtemperature increased. Along the same gradient, the before-noon superiority of the photosynthesis be-came evident, and the photosynthesis rate and the light use efficiency (LUE ) increased, while the transp-iration rate decreased, thus the water use efficiency (WUE ) increased notably, and the leaf water contentdecreased gradually. From the east to the west, the plants took a water-saving strategy step by step withhigher photosynthesis rate and lower transpiration rate. These physiological changes in the plants wereadaptable to the conditions of light, temperature and humidity in the habitat of the plants, and might be thebiological foundation for the geographical transition among C. microphylla , C. davazamcii and C. korshinskii.(2) The adaptation of photosynthetic system of C. microphylla , C. davazamcii and C. korshinskii to PAR, airhumidity and temperature exhibited the interspecific continuity, which was consistent with theenvironmental gradient. In different species and different sites, the diurnal changes of net photosynthesisrate, the daily cumulative value of net photosynthesis, the diurnal changes of transpiration rate, the dailycumulative value of transpiration, the water use efficiency and the diurnal changes of leaf water contentvaried with longitudinal descent (from the east to the west). The characteristics of photosynthesis andwater metabolism indicated that the geographical transition among C. microphylla , C. davazamcii and C.korshinskii was in gradual change, and these three species formed a geographical cline. 展开更多
关键词 Caragana microphylla C. davazamcii C. korshinskii geographical transition PHOTOSYNTHESIS water metabolism
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Design and Implementation of Biogas Plants Geographic Information System 被引量:5
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作者 唐雪梦 陈理 吴树彪 《Agricultural Science & Technology》 CAS 2011年第7期1075-1078,共4页
[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user... [Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user's need and function demand were studied.Sub-system function was divided.By using SuperMap IS.NET,C# and SQL Server 2005 as the database and WebGIS frame,the system spatial and attribute database were designed so as to realize the WebGIS software of biogas project in Beijing.[Result] The system provided application platform for the distribution of biogas project information.User can realize the submission and inquiry the feedback of biogas project information based on system application right etc,so as to visually,fully and precisely inquiry project data.Based on the comprehensive analysis of data,the current state of biogas project and change trend were studied and decided.[Conclusion] The system provided convenience and services to relevant departments' planning and management of biogas project. 展开更多
关键词 Biogas plant geographic Informaiton System SuperMap IS.NET
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Research on Geographical Indications and Cultural Heritage of Famous Tea in Hubei 被引量:1
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作者 孙志国 黄莉敏 +2 位作者 熊晚珍 王树婷 钟学斌 《Agricultural Science & Technology》 CAS 2012年第3期502-506,536,共6页
In the study, analysis was made on present situation and development measures of geographical indications and cultural heritage protection of famous teas in Hubei Province. In addition, 8 related suggestions were prop... In the study, analysis was made on present situation and development measures of geographical indications and cultural heritage protection of famous teas in Hubei Province. In addition, 8 related suggestions were proposed as well. 展开更多
关键词 TEA geographical indication Cultural heritage Tangible cultural heritage Intangible cultural heritage Hubei Province
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Research on Geographical Environment and Culture Symbiosis of Chishui River Basin 被引量:1
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作者 王爱华 彭恩 《Journal of Landscape Research》 2011年第11期81-85,共5页
This paper took Chishui River Basin as the research object,and pointed out that its culture,which reflected local life and production and was featured with regional characteristics as well as abundant cultural connota... This paper took Chishui River Basin as the research object,and pointed out that its culture,which reflected local life and production and was featured with regional characteristics as well as abundant cultural connotation,was constituted by native natural and cultural geography,folk customs and historical feature.The relation between Chishui salt path and salt business culture under the typical closed and half-closed geographical environment was analyzed to indicate that the realignment of Chishui River had brought prosperity of Chishui River,booming of commercial towns,and development of ancient architectures and guild hall culture.The relation between rich natural resources and production and life culture of Chishui River was explained to show that Danxia landform nurtured stone culture,Chishui River resources cultivated fishing culture,special hydrogeological environment fostered liquor culture represented by Maotai,and Bamboo culture accumulated for hundreds of years.Finally,it introduced military culture and the spirit of the Long March forming based on the special location of Chishui River.It emphasized that geological environment was the important basis for human's survival and played an immeasurable role in the cultural development of a region. 展开更多
关键词 Chishui RIVER BASIN CULTURE geographicAL ENVIRONMENT SYMBIOSIS
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Spatio-temporal characteristics of population and economy in transitional geographic space at the southern end of"Hu Huan-yong Line" 被引量:3
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作者 DENG Wei CHENG Yu-fang +3 位作者 YU Huan PENG Li KONG Bo HOU Yu-ting 《Journal of Mountain Science》 SCIE CSCD 2022年第2期350-364,共15页
"Hu Huan-yong Line(Hu Line)"depicts a geographical pattern of China’s population distribution.Its essence is the regionality of humanland relationship and reflects basic characteristics and laws of human be... "Hu Huan-yong Line(Hu Line)"depicts a geographical pattern of China’s population distribution.Its essence is the regionality of humanland relationship and reflects basic characteristics and laws of human beings’adaptation to the natural environment.With the development of the times and the progress of modern science and technology,especially the rapid urbanization and construction of transportation network system in China,the connection between economic and geographical space has been continuously strengthened.The geographical transition zones from mountain areas to plains,i.e.,transitional geographical space,have promoted the changes in human-land relationships through population migration and agglomeration.Taking Sichuan-Yunnan provinces at the southern end of Hu Line as study area,this study analyzed the spatial correlation between population distribution and economy in this region,explored the pattern of geographical agglomeration and deagglomeration,and explained the changing characteristics of humanland relationship in transitional geographic space using global Moran’s I index,global regression model(GRM)and geographically weighted regression(GWR).The results show that population and Gross Domestic Product(GDP)have significant spatial dependence to this region,with obvious aggregation in geographical distribution and positive autocorrelation;comparing with the general least square model,the GWR model incorporating spatial effect was more suitable for revealing the distribution characteristics of geographical elements,with fine results and better fitting;the spatial model of population and GDP as well as the spatio-temporal evolution model of their changes,all of them strongly indicated that Normalized Difference Vegetation Index(NDVI)and road density were important factors governing the spatial differentiation of population and economy;under the rapid development of regional economy and continuous evolution of urban-rural relations,rural transformation and spatial reconstruction promoted the change of population migration and agglomeration. 展开更多
关键词 Hu Huan-yong Line Spatial correlation geographically weighted regression Population distribution Transitional geographic space
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Selecting suitable sites for mountain ginseng(Panax ginseng)cultivation by using geographically weighted logistic regression 被引量:1
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作者 HAN Hee JANG Kwang-min CHUNG Joo-sang 《Journal of Mountain Science》 SCIE CSCD 2017年第3期492-500,共9页
With the well-being trends to pursue a healthy life, mountain ginseng(Panax ginseng) is rising as one of the most profitable forest products in South Korea. This study was aimed at evaluating a new methodology for ide... With the well-being trends to pursue a healthy life, mountain ginseng(Panax ginseng) is rising as one of the most profitable forest products in South Korea. This study was aimed at evaluating a new methodology for identifying suitable sites for mountain ginseng cultivation in the country. Forest vegetation data were collected from 46 sites and the spatial distribution of all sites was analyzed using GIS data for topographic position, landform, solar radiation, and topographic wetness. The physical and chemical properties of the soil samples, including moisture content, p H, organic matter, total nitrogen, exchangeable cations, available phosphorous, and soil texture, were analyzed. The cultivation suitability at each site was assessed based on the environmental conditions using logistic regression(LR) and geographically weighted logistic regression(GWLR) and the results of both methods were compared. The results show that the areas with northern aspect and higher levels of solar radiation, moisture content, total nitrogen, and sand ratio are more likely to be identified as suitable sites for ginseng cultivation. In contrast to the LR, the spatial modeling with the GWLR results in an increase in the model fitness and indicates that a significant portion of spatialautocorrelation in the data decreases. A higher value of the area under the receiver operating characteristic(ROC) curve presents a better prediction accuracy of site suitability by the GWLR. The geographically weighted coefficient estimates of the model are nonstationary, and reveal that different site suitability is associated with the geographical location of the forest stands. The GWLR increases the accuracy of selecting suitable sites by considering the geographical variations in the characteristics of the cultivation sites. 展开更多
关键词 Panax ginseng Site suitability Logistic regression geographically weighted logistic regression geographic Information System South Korea
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Application of Remote Sensing and Geographic Information System in Land Use and Land Cover Change
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作者 王静 经卓玮 +2 位作者 马友华 王强 於忠祥 《Agricultural Science & Technology》 CAS 2014年第1期144-147,共4页
The integration and application of remote sensing (RS) and geographic in-formation system (GIS) in the study of the Land Use and Land Cover Change (LUCC) were summarized, as wel as researches on the monitoring d... The integration and application of remote sensing (RS) and geographic in-formation system (GIS) in the study of the Land Use and Land Cover Change (LUCC) were summarized, as wel as researches on the monitoring dynamic changes in LUCC, driving force and application examples of the integration and the application of RS and GIS in simulation research. The methods and technical ap-proaches of RS and GIS in LUCC research were discussed. Views on the existing problems of the integration and the application of RS and GIS were put forward, and the future developing direction of LUCC technology was forecasted. 展开更多
关键词 Land cover/land use Remote sensing (RS) geographic information sys-tem (GIS) Integration of RS and GIS
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Analysis of the Correlation between the Geographical Distribution of Populus euphratica Oliv. and the Climatic Environment
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作者 杨银科 阎正龙 《Agricultural Science & Technology》 CAS 2012年第7期1450-1455,共6页
[Objective] This research was to study the correlation regional climatic characteristics and changing geographic distribution of Populus euphratica Oliv. (Salicaceae), as well as the adaption of Populus euphratica Oli... [Objective] This research was to study the correlation regional climatic characteristics and changing geographic distribution of Populus euphratica Oliv. (Salicaceae), as well as the adaption of Populus euphratica Oliv. to the climatic environment. [Method] The climatic characteristics, water source, groundwater and soil type in the distribution regions of Populus euphratica Oliv. and the effect of long-term human activities were comprehensively analyzed based an overview of Populus euphratica Oliv. and its distribution. [Result] Specific regional climatic characteristics and long term human activities are the principle determinants for the growth of Populus euphratica Oliv. The change of leaf shape is a distinct feature of Populus euphratica Oliv. in adapting to the climatic environment. Populus euphratica Oliv. withstands various environmental stresses by means of in vivo synthesis, transport and conversion of secondary phenolic metabolites. Effective protection and rehabilitation measures, and ecological water transport have obvious effect on the restoration and reconstruction of damaged ecological environment of Populus euphratica oasis. [Conclusion] This study is of great significance for the restoration of ecological environment in the arid inland regions, north-west China. 展开更多
关键词 POPULUS EUPHRATICA Oliv. (Salicaceae) geographic distribution Climatic and environmental characteristics CORRELATION ANALYSIS
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Classification Method for Dongting Lake Wetland Based on Geographic Information
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作者 朱晓荣 张怀清 《Agricultural Science & Technology》 CAS 2012年第10期2175-2179,2196,共6页
[Objective] This study aimed to improve the accuracy of remote sensing classification for Dongting Lake Wetland.[Method] Based on the TM data and ground GIS information of Donting Lake,the decision tree classification... [Objective] This study aimed to improve the accuracy of remote sensing classification for Dongting Lake Wetland.[Method] Based on the TM data and ground GIS information of Donting Lake,the decision tree classification method was established through the expert classification knowledge base.The images of Dongting Lake wetland were classified into water area,mudflat,protection forest beach,Carem spp beach,Phragmites beach,Carex beach and other water body according to decision tree layers.[Result] The accuracy of decision tree classification reached 80.29%,which was much higher than the traditional method,and the total Kappa coefficient was 0.883 9,indicating that the data accuracy of this method could fulfill the requirements of actual practice.In addition,the image classification results based on knowledge could solve some classification mistakes.[Conclusion] Compared with the traditional method,the decision tree classification based on rules could classify the images by using various conditions,which reduced the data processing time and improved the classification accuracy. 展开更多
关键词 geographic information Decision tree classification
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A multi-Agent system architecture for geographic information gathering
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作者 高刚毅 王申康 《Journal of Zhejiang University Science》 CSCD 2004年第11期1367-1373,共7页
World Wide Web (WWW) is a vast repository of information, including a great deal of geographic information. But the location and retrieval of geographic information will require a significant amount of time and effort... World Wide Web (WWW) is a vast repository of information, including a great deal of geographic information. But the location and retrieval of geographic information will require a significant amount of time and effort. In addition, different users usually have different views and interests in the same information. To resolve such problems, this paper first proposed a model of geographic information gathering based on multi-Agent (MA) architecture. Then based on this model, we construct a prototype system with GML (Geography Markup Language). This system consists of three tiers-Client, Web Server and Data Resource. Finally, we expatiate on the process of Web Server. 展开更多
关键词 GIS (geographic Information System) MULTI-AGENT geographic information GML
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Establishment of Geographic Information Database of Benxi City and Its Application in Analysis of Climatic Resources
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作者 宋仁锋 高艳波 宋长远 《Meteorological and Environmental Research》 CAS 2010年第1期68-70,74,共4页
Based on 1:50 000 basic geographic information data,the digital elevation,longitude,latitude,slope,aspect and all kinds of terrain databases of Benxi City (China) were established with Arcgis 9.2 software.Township bou... Based on 1:50 000 basic geographic information data,the digital elevation,longitude,latitude,slope,aspect and all kinds of terrain databases of Benxi City (China) were established with Arcgis 9.2 software.Township boundary database was established by digitizing map,and the township information was amended according to the reality.Taking the elaborate simulation of spatial distribution of annual mean temperature as an example,the paper reports the application of the geographic information database in analysis of climatic resources. 展开更多
关键词 geographic information system Climatic resources geographic information database Benxi City China
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Geographic Drone-based Route Optimization Approach for Emergency Area Ad-Hoc Network
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作者 V.Krishnakumar R.Asokan 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期985-1000,共16页
Wireless sensor Mobile ad hoc networks have excellent potential in moving and monitoring disaster area networks on real-time basis.The recent challenges faced in Mobile Ad Hoc Networks(MANETs)include scalability,local... Wireless sensor Mobile ad hoc networks have excellent potential in moving and monitoring disaster area networks on real-time basis.The recent challenges faced in Mobile Ad Hoc Networks(MANETs)include scalability,localization,heterogeneous network,self-organization,and self-sufficient operation.In this background,the current study focuses on specially-designed communication link establishment for high connection stability of wireless mobile sensor networks,especially in disaster area network.Existing protocols focus on location-dependent communications and use networks based on typically-used Internet Protocol(IP)architecture.However,IP-based communications have a few limitations such as inefficient bandwidth utilization,high processing,less transfer speeds,and excessive memory intake.To overcome these challenges,the number of neighbors(Node Density)is minimized and high Mobility Nodes(Node Speed)are avoided.The proposed Geographic Drone Based Route Optimization(GDRO)method reduces the entire overhead to a considerable level in an efficient manner and significantly improves the overall performance by identifying the disaster region.This drone communicates with anchor node periodically and shares the information to it so as to introduce a drone-based disaster network in an area.Geographic routing is a promising approach to enhance the routing efficiency in MANET.This algorithm helps in reaching the anchor(target)node with the help of Geographical Graph-Based Mapping(GGM).Global Positioning System(GPS)is enabled on mobile network of the anchor node which regularly broadcasts its location information that helps in finding the location.In first step,the node searches for local and remote anticipated Expected Transmission Count(ETX),thereby calculating the estimated distance.Received Signal Strength Indicator(RSSI)results are stored in the local memory of the node.Then,the node calculates the least remote anticipated ETX,Link Loss Rate,and information to the new location.Freeway Heuristic algorithm improves the data speed,efficiency and determines the path and optimization problem.In comparison with other models,the proposed method yielded an efficient communication,increased the throughput,and reduced the end-to-end delay,energy consumption and packet loss performance in disaster area networks. 展开更多
关键词 Mobile ad hoc networks(MANETs) geographical graph-based mapping(GGM) geographic drone based route optimization data speed anchor node’s
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