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Spatial-Temporal Dynamics of Dongzhaigang Mangrove Forests on Hainan Island,China:Evidence from Landsat Observations(1988–2019)
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作者 Bing Tu Kang Peng +4 位作者 Xianjun Xie Lu Yan Yamin Deng Yiqun Gan Qinghua Li 《Journal of Earth Science》 2026年第1期289-302,共14页
The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang... The goal of this study was to determine the spatiotemporal characteristics of mangrove distribution and fragmentation patterns from 1988 through 2019 in Dongzhaigang.Land cover datasets were generated for Dongzhaigang for multiple years via a decision tree method based on a classification and regression tree(CART)algorithm using Landsat time series images.Spatiotemporal transform and fragmentation patterns of mangrove distribution were separately assessed with a transfer matrix of land cover types and a landscape pattern index.The classification method combined with multi-band images showed good accuracy,with overall accuracy higher than 90%.Mangrove areas in 1988,1999,2009,and 2019 were 2050,1875,1818,and 1750 ha,respectively,with decreases mainly due to conversion to aquaculture ponds and farmland.A mangrove growth index(MGI)was proposed,reflecting the water-mangrove relationship,showing positive mangrove growth from 1988–2009 and negative growth from 2009–2019.Study results indicated anthropogenic factors play a leading role in the extent and scale of mangrove effects over the past 30 years.According to the analysis results,corresponding management and protection measures are proposed to provide reference for the sustainable development of Dongzhaigang Mangrove Wetland ecosystem. 展开更多
关键词 mangrove forests spatial-temporal data Hainan Island decision trees Landsat image
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A novel deviation measurement for scheduled intelligent transportation system via comparative spatial-temporal path networks
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作者 Daozhong Feng Jiajian Lai +1 位作者 Wenxuan Wei Bin Hao 《Digital Communications and Networks》 2026年第1期101-118,共18页
Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-netwo... Transit managers can use Intelligent Transportation System technologies to access large amounts of data to monitor network status.However,the presentation of the data lacks structural information.Existing single-network description technologies are ineffective in representing the temporal and spatial characteristics simultaneously.Therefore,there is a need for complementary methods to address these deficiencies.To address these limitations,this paper proposes an approach that combines Network Snapshots and Temporal Paths for the scheduled system.A dual information network is constructed to assess the degree of operational deviation considering the planning tasks.To validate the effectiveness,discussions are conducted through a modified cosine similarity calculation on theoretical analysis,delay level description,and the ability to identify abnormal dates.Compared to some state-of-the-art methods,the proposed method achieves an average Spearman delay correlation of 0.847 and a relative distance of 3.477.Furthermore,case analyses are invested in regions of China's Mainland,Europe,and the United States,investigating both the overall and sub-regional network fluctuations.To represent the impact of network fluctuations in sub-regions,a response loss value was developed.The times that are prone to fluctuations are also discussed through the classification of time series data.The research can offer a novel approach to system monitoring,providing a research direction that utilizes individual data combined to represent macroscopic states.Our code will be released at https://github.com/daozhong/STPN.git. 展开更多
关键词 Intelligent transportation system Air traffic network Deviation measurement spatial-temporal path networks Operational monitoring
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Spatial-temporal distribution and emission of urban scale air pollutants in Hefei based on Mobile-DOAS 被引量:1
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作者 Zhidong Zhang Pinhua Xie +8 位作者 Ang Li Min Qin Jin Xu Zhaokun Hu Xin Tian Feng Hu Yinsheng Lv Jiangyi Zheng Youtao Li 《Journal of Environmental Sciences》 2025年第5期238-251,共14页
As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limite... As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban expansion.However,there has been limited research in recent years on the spatial-temporal distribution and emission of its atmospheric pollutants.To address this,this study conducted mobile observations of urban roads using the Mobile-DOAS instrument from June 2021 to May 2022.The monitoring results exhibit a favourable consistent with TROPOMI satellite data and ground monitoring station data.Temporally,there were pronounced seasonal variations in air pollutants.Spatially,high concentration of HCHO and NO_(2)were closely associated with traffic congestion on roadways,while heightened SO_(2)levels were attributed to winter heating and industrial emissions.The study also revealed that with the implementation of road policies,the average vehicle speed increased by 95.4%,while the NO concentration decreased by 54.4%.In the estimation of urban NO_(x)emission flux,it was observed that in temporal terms,compared with inventory data,the emissions calculated viamobile measurements exhibitedmore distinct seasonal patterns,with the highest emission rate of 349 g/sec in winter and the lowest of 142 g/sec in summer.In spatial terms,the significant difference in emissions between the inner and outer ring roads also suggests the presence of the city’s primary NO_(x)emission sources in the area between these two rings.This study offers data support for formulating the next phase of air pollution control measures in urban areas. 展开更多
关键词 Mobile-DOAS HCHO NO_(2) SO_(2) spatial-temporal distribution NOx emission
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Social alienation in patients with inflammatory bowel diseases:A latent profileanalysis 被引量:1
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作者 Qingyu Wang Junyi Gu +6 位作者 Zheng Lin Sha Li Meijing Zhou Jiefeng Yang Hantian Cheng Jiali Chen Yang Lei 《International Journal of Nursing Sciences》 2025年第4期335-343,I0002,I0003,共11页
Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling a... Objectives:The study aimed to explore social alienation types in patients with inflammatorybowel diseases(IBD)and identify influencingfactors.Methods:This cross-sectional study was conducted using purposive sampling among patients with IBD from July 2022 to July 2023.Patients were assessed using the Generalized Social Alienation Scale(GSAS),the Brief Illness Perception Questionnaire(B-IPQ),the Hospital Anxiety and Depression Scale(HADS),and the Medical Coping Modes Questionnaire(MCMQ).Demographic and disease-related characteristics were also collected.Latent profileanalysis(LPA)was used to identify potential subgroups of social alienation.Univariate analysis and multicollinearity analysis were conducted to explore the influencing factors,followed by multiple regression analysis to evaluate the effect of influencingfactors on social alienation.Results:Three distinct profilesof social alienation were identified:integrated-low alienation group(n=61,20.20%),accommodative-moderate alienation group(n=195,64.57%),and maladaptive-high alienation group(n=46,15.23%).Seven characteristics were associated with the profile’smembership:self-perceived financialstress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode.Conclusions:Patients with IBD were categorized into three subgroups based on social alienation levels.Financial stress,malnutrition risk,disease duration,illness comprehensibility,anxiety,depression,and acceptance-resignation coping mode were key predictors of the subgroup membership.Targeted interventions should be developed to mitigate the negative effects of social alienation,with a focus on improving illness perception,alleviating anxiety and depression,and promoting effective coping strategies. 展开更多
关键词 Inflammatory bowel diseases Influencing factors Latent profile analysis NURSING Social alienation
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Exploring the Alienation of Digital Labor in the Era of Digital Capitalism-Based on Marx’s Theory of Alienated Labor
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作者 ZHANG Wanruo 《Cultural and Religious Studies》 2025年第2期82-88,共7页
In the era of digital capitalism with the explosion of data and information,human society will be greatly affected by digital capital,and all walks of life will be included in the chain of information-based labor prod... In the era of digital capitalism with the explosion of data and information,human society will be greatly affected by digital capital,and all walks of life will be included in the chain of information-based labor production,giving rise to a new type of labor form called“digital labor”.This paper discusses the alienation of digital labor in the context of digital capitalism,take Marx’s theory of alienated labor as the perspective,and analyze the fourfold alienation of digital labor in terms of producing products,labor process,self-realization of laborers,and social relations by combing the historical development of digital labor.Based on the above analysis,the article proposes the logical and practical paths to crack the alienation of digital labor:improve media literacy and thinking discernment,make full use of the positive effects of digital technology,and strengthen the governance of digital platforms,in order to build a fairer and more shared digital labor environment,and to realize the self-emancipation of laborers and the healthy development of the digital economy. 展开更多
关键词 digital labor digital capitalism labor alienation Marxian theory of alienated labor
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Social Alienation in Adolescents with Depression from an Interaction Perspective: A Qualitative Research
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作者 Peiqing Li Qunfang Miao +1 位作者 Hanyi Ning Yijing Xu 《Journal of Clinical and Nursing Research》 2025年第6期121-132,共12页
Objective:This study aims to explore the experiences of social alienation among adolescents with depression,providing practical This study aims to explore the experiences of social alienation among adolescents with de... Objective:This study aims to explore the experiences of social alienation among adolescents with depression,providing practical This study aims to explore the experiences of social alienation among adolescents with depression,providing practical guidance for improving their interpersonal relationships and facilitating their reintegration into society.Methods:This qualitative research was conducted following the conventional content analysis method.20 adolescents with depression were employed to select from June to August 2024 for face-to-face semi-structured interviews.The collected data were analyzed using Colaizzi's seven-step method.Results:Three themes and eight sub-themes were analyzed and identified:individual level(feelings of helplessness and powerlessness,cognitive distortion,avoidance and withdrawal),family level(lack of family awareness,family conflict),social level(limitations of academic stress and social circle,lack and degradation of skills,generalization of virtual reality,social“stigma”).Conclusion:Adolescents with depression experience complex social alienation.Healthcare providers should enhance their self-awareness and social adaptation skills,improve family dynamics,and provide a comprehensive range of services and services to help them to cope with the challenges of depression.Healthcare providers should enhance their self-awareness and social adaptation skills,improve family dynamics,strengthen communication,bolster family support systems,and collaborate to develop comprehensive social networks and psychological services.This will create a supportive social atmosphere to help adolescents gradually alleviate their feelings of social alienation. 展开更多
关键词 DEPRESSION Adolescents Social alienation The interactive perspective Qualitative research
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Spatial-Temporal Coupling and Determinants of Digital Economy and High-Quality Development: Insights from the Yellow River Region
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作者 Zhang Shu Wang Kangqing Guo Jinlong 《全球城市研究(中英文)》 2025年第2期1-17,149,共18页
In the current situation of decelerating economic expansion,examining the digital economy(DE)as a novel economic model is beneficial for the local economy’s sustainable and high-quality development(HQD).We analyzed p... In the current situation of decelerating economic expansion,examining the digital economy(DE)as a novel economic model is beneficial for the local economy’s sustainable and high-quality development(HQD).We analyzed panel data from the Yellow River(YR)region from 2013 to 2021 and discovered notable spatial variances in the composite index and coupling coordination of the two systems.Specifically,the downstream region exhibited the highest coupling coordination,while the upstream region had the lowest.We identified that favorable factors such as economic development,innovation,industrial upgrading,and government intervention can bolster the coupling.Our findings provide a valuable framework for promoting DE and HQD in the YR region. 展开更多
关键词 High-quality development Digital economy spatial-temporal coupling the Yellow River region
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Analysis and Governance of the Phenomenon of Consumption Alienation in the Context of E-commerce Festival Creation
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作者 Ying Tao Guanghua Xiong 《Proceedings of Business and Economic Studies》 2025年第3期223-230,共8页
In modern society,influenced by mass culture and internal alienation,people experience alienation in the consumption field.The impulsive and excessive consumption of consumers not only reflects the changes in consumpt... In modern society,influenced by mass culture and internal alienation,people experience alienation in the consumption field.The impulsive and excessive consumption of consumers not only reflects the changes in consumption culture but is also the result of the combined action of market,technological,and psychological factors.The shopping spree in the context of e-commerce festival creation is due to the hard control of science and technology and the soft penetration of mass culture,which fully invade individuals’work and life,evoke false and excessive demands,and thus generate consumption.The practical path to get rid of consumption alienation and return to rational consumption can start from three aspects:aesthetic awakening,concept guidance,and environmental regulation. 展开更多
关键词 Consumption alienation Symbolic consumption Consumption culture Internet celebrity economy
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MSSTGCN: Multi-Head Self-Attention and Spatial-Temporal Graph Convolutional Network for Multi-Scale Traffic Flow Prediction
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作者 Xinlu Zong Fan Yu +1 位作者 Zhen Chen Xue Xia 《Computers, Materials & Continua》 2025年第2期3517-3537,共21页
Accurate traffic flow prediction has a profound impact on modern traffic management. Traffic flow has complex spatial-temporal correlations and periodicity, which poses difficulties for precise prediction. To address ... Accurate traffic flow prediction has a profound impact on modern traffic management. Traffic flow has complex spatial-temporal correlations and periodicity, which poses difficulties for precise prediction. To address this problem, a Multi-head Self-attention and Spatial-Temporal Graph Convolutional Network (MSSTGCN) for multiscale traffic flow prediction is proposed. Firstly, to capture the hidden traffic periodicity of traffic flow, traffic flow is divided into three kinds of periods, including hourly, daily, and weekly data. Secondly, a graph attention residual layer is constructed to learn the global spatial features across regions. Local spatial-temporal dependence is captured by using a T-GCN module. Thirdly, a transformer layer is introduced to learn the long-term dependence in time. A position embedding mechanism is introduced to label position information for all traffic sequences. Thus, this multi-head self-attention mechanism can recognize the sequence order and allocate weights for different time nodes. Experimental results on four real-world datasets show that the MSSTGCN performs better than the baseline methods and can be successfully adapted to traffic prediction tasks. 展开更多
关键词 Graph convolutional network traffic flow prediction multi-scale traffic flow spatial-temporal model
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Current Status and Influencing Factors of Social Alienation Among Young and Middle-Aged Stroke Patients in Dali
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作者 Yu Cheng Haojie Zhou +2 位作者 Xianjuan Zhang Yanshan Chen Guifeng Zhao 《Journal of Clinical and Nursing Research》 2025年第6期101-110,共10页
Objective:To explore the current status of social alienation and its influencing factors among young and middle-aged stroke patients in Dali.Methods:A convenience sampling method was used to survey 385 young and middl... Objective:To explore the current status of social alienation and its influencing factors among young and middle-aged stroke patients in Dali.Methods:A convenience sampling method was used to survey 385 young and middle-aged stroke patients in a tertiary hospital in Dali from December 2024 to July 2025.Questionnaires including general demographic information,the General Alienation Scale,the Athens insomnia scale,and others were administered.Results:The social alienation score of young and middle-aged stroke patients in Dali was(35.67±3.46).Univariate analysis showed that general demographic factors[education level,monthly household income,whether it was the first onset,presence of sequelae,disease duration,activities of daily living(ADL,Barthel Index)],social support,stigma,self-perceived burden,anxiety and depression,and sleep status were influencing factors of social alienation(P<0.05).Regression analysis indicated that social support,anxiety and depression,disease duration,stigma,presence of sequelae,and self-care ability were significant influencing factors of social alienation(P<0.01),explaining 65.3%of the total variance.Conclusion:The level of social alienation among young and middle-aged stroke patients in Dali is relatively low.Special attention should be paid to patients with a disease duration of<7 days,those with sequelae,moderate-to-severe dependence in self-care,low social support,high stigma,and high levels of anxiety and depression,to effectively reduce their social alienation. 展开更多
关键词 Young and middle-aged stroke Influencing factors Social alienation
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Alienation and Life Satisfaction:Mediation Effects of Social Identity and Hope among University Students
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作者 Shu-Hsuan Chang Der-Fa Chen +4 位作者 Jing-Tang Sie Kai-Jie Chen Zhe-Wei Liao Tai-Lung Chen Yao-Chung Cheng 《International Journal of Mental Health Promotion》 2025年第12期1907-1927,共21页
Background:Interpersonal alienation has increasingly been recognized as a salient risk factor affecting university students’psychological adjustment and life satisfaction.Guided by Social Identity and Self-Categoriza... Background:Interpersonal alienation has increasingly been recognized as a salient risk factor affecting university students’psychological adjustment and life satisfaction.Guided by Social Identity and Self-Categorization theories,this study examines how alienation influences life satisfaction through the mediating roles of social identity and hope.Methods:This study surveyed 492 Taiwan Region of China undergraduate students(53.7 percent female,mean age 21.08 years)from 60 universities using convenience sampling in May 2023.Data were collected through an online questionnaire distributed via faculty-managed teaching media platforms.Measures included perceived social identity,state hope,interpersonal alienation,and life satisfaction.All instrumentswere adapted from validated scales,translated into traditional Chinese through back-translation,and reviewed by experts to ensure content validity and cultural relevance.Statistical analyses were conducted using SPSS 20 and SmartPLS 4.0.Results:Harman’s single-factor test indicated no significant common method bias.Measurement model analyses demonstrated satisfactory reliability,convergent validity,and absence of multicollinearity.All four hypothesized paths were supported:interpersonal alienation negatively predicted life satisfaction,with perceived social identity and hope serving as individual and sequential mediators.The model explained 10.5%of the variance in social identity,25.3%in hope,and 49.6%in life satisfaction.Group comparisons revealed that male students reported significantly higher hope and life satisfaction than females,and first-year students experienced greater alienation than upper-level peers.Conclusion:This study elucidates how interpersonal alienation undermines life satisfaction among university students and highlights the protective roles of social identity and hope.Findings underscore the importance of fostering psychological resources that promote resilience and well-being.The results offer practical implications for designing educational programs that enhance students’sense of belonging,optimism,and emotional strength.These insights contribute to a deeper theoretical understanding of the mechanisms linking alienation and life satisfaction and inform strategies to support student adaptation and flourishing in higher education. 展开更多
关键词 Interpersonal alienation perceived social identity perceived hope satisfaction with life sequential mediation model
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A structured distributed learning framework for irregular cellular spatial-temporal traffic prediction
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作者 Xiangyu Chen Kaisa Zhang +4 位作者 Gang Chuai Weidong Gao Xuewen Liu Yibo Zhang Yijian Hou 《Digital Communications and Networks》 2025年第5期1457-1468,共12页
Spatial-temporal traffic prediction technology is crucial for network planning,resource allocation optimizing,and user experience improving.With the development of virtual network operators,multi-operator collaboratio... Spatial-temporal traffic prediction technology is crucial for network planning,resource allocation optimizing,and user experience improving.With the development of virtual network operators,multi-operator collaborations,and edge computing,spatial-temporal traffic data has taken on a distributed nature.Consequently,noncentralized spatial-temporal traffic prediction solutions have emerged as a recent research focus.Currently,the majority of research typically adopts federated learning methods to train traffic prediction models distributed on each base station.This method reduces additional burden on communication systems.However,this method has a drawback:it cannot handle irregular traffic data.Due to unstable wireless network environments,device failures,insufficient storage resources,etc.,data missing inevitably occurs during the process of collecting traffic data.This results in the irregular nature of distributed traffic data.Yet,commonly used traffic prediction models such as Recurrent Neural Networks(RNN)and Long Short-Term Memory(LSTM)typically assume that the data is complete and regular.To address the challenge of handling irregular traffic data,this paper transforms irregular traffic prediction into problems of estimating latent variables and generating future traffic.To solve the aforementioned problems,this paper introduces split learning to design a structured distributed learning framework.The framework comprises a Global-level Spatial structure mining Model(GSM)and several Nodelevel Generative Models(NGMs).NGM and GSM represent Seq2Seq models deployed on the base station and graph neural network models deployed on the cloud or central controller.Firstly,the time embedding layer in NGM establishes the mapping relationship between irregular traffic data and regular latent temporal feature variables.Secondly,GSM collects statistical feature parameters of latent temporal feature variables from various nodes and executes graph embedding for spatial-temporal traffic data.Finally,NGM generates future traffic based on latent temporal and spatial feature variables.The introduction of the time attention mechanism enhances the framework’s capability to handle irregular traffic data.Graph attention network introduces spatially correlated base station traffic feature information into local traffic prediction,which compensates for missing information in local irregular traffic data.The proposed framework effectively addresses the distributed prediction issues of irregular traffic data.By testing on real world datasets,the proposed framework improves traffic prediction accuracy by 35%compared to other commonly used distributed traffic prediction methods. 展开更多
关键词 Network measurement and analysis Distributed learning Irregular time series Cellular spatial-temporal traffic Traffic prediction
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Spatial-temporal Evolvement Characteristics of Climate Productivity for the Plants on Inner Mongolia Desert Steppe 被引量:5
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作者 韩芳 苗百岭 +3 位作者 郭瑞清 李兴华 那日苏 王海 《Meteorological and Environmental Research》 CAS 2010年第5期76-79,共4页
Thornthwaite Memorial model and other statistic methods were used to calculate the climate-productivity of plants with the meteorological data from 1961 to 2007 at 9 stations distributed on Inner Mongolia desert stepp... Thornthwaite Memorial model and other statistic methods were used to calculate the climate-productivity of plants with the meteorological data from 1961 to 2007 at 9 stations distributed on Inner Mongolia desert steppe.The spatial and temporal variation characteristics of climate-productivity were analyzed by using the methods of the tendency rate of the climate trend,accumulative anomaly,and spatial difference and so on.The results showed that the climate-productivity kept linear increased trend over Inner Mongolia desert steppe in recent 47 years,but not significant.In spatial distribution,the climate-productivity reduced with the increased latitude.The climate-productivity in southwest part of Inner Mongolia desert steppe was growing while that in the southeast was reducing.The variation rate of the climate-productivity increased from the northwest part to the southeast part of Inner Mongolia desert steppe.In recent 47 years,the climate-productivity in southeast Jurh underwent the greatest decreasing extent,and the region was the sensitive area of the climate-productivity variation. 展开更多
关键词 Desert steppe Climate productivity spatial-temporal distribution Variation rate China
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Study on the Relationship among Forest Fire,Temperature and Precipitation and Its Spatial-temporal Variability in China 被引量:9
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作者 吕爱锋 《Agricultural Science & Technology》 CAS 2011年第9期1396-1400,共5页
[Objective] The aim was to discuss the relationship between forest fire and meterological elements (precipitation and temprature) in each region of China.[Method] Firstly,the average precipitation and temperature in... [Objective] The aim was to discuss the relationship between forest fire and meterological elements (precipitation and temprature) in each region of China.[Method] Firstly,the average precipitation and temperature in forest area of each province in fire season were obtained based on meterological data,forest distribution data,seasonal and monthly data of forest fire in China.Secondly,the relationship among forest fire area,precipitation and temperature was discussed through temporal and correlation analysis.[Result] The changes of precipitation and temperature with time could reflect the annual variation of fire area well.Forest fire area went up with the decrease of precipitation and increase of temprature,and visa versa.Meanwhile,there existed diffirences in the relationship in various regions over time.Correlation analyses revealed that there was positive correlation between forest fire area and temperature,especailly Northwest China (R=0.367,P〈0.01),Southwest China (R=0.327,P〈0.05),South China (R=0.33,P〈0.05),East China (R=0.516,P〈0.01) and Xinjiang (R=0.447,P〈0.05) with obviously positive correlation.At the same time,the correlation between forest fire area and precipitation was significantly positive in Northwest China (R=0.482,P〈0.01),while it was significantly negaive in South China (R=-0.323,P=0.03),but there was no significant correlation in other regions.[Conclusion] Relationships between forest fire and meteorological elements (precipitation and temprature) revealed in the study would be useful for fire provention and early warning in China. 展开更多
关键词 Forest fire PRECIPITATION TEMPERATURE spatial-temporal variability
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Spatial-Temporal Distribution Characteristics and Limiting Factors of Medium-low Yield Farmland in Tianjin
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作者 潘洁 吕雄杰 +1 位作者 肖辉 陆文龙 《Agricultural Science & Technology》 CAS 2015年第3期578-582,共5页
[Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [... [Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [Method] Based on the statistical date of Tianjin and its relevant counties and districts, the yield standard was set up to classify high-yield, medium-yield and low-yield farmland in Tianjin. The author analyzed area change of medium-low yield farmland in six agricultural counties and districts (including Jixian County, Wuqing District, Baodi District, Ninghe County, Jinghai County and Dagang district of Binghai New Area) from 1980 to 2010. [Result] The results showed that the average yield of grain rose from 2 445 kg/hm^2 in 1980 to 5 130 kg/hm^2 in 2010, increasing 109.82%. The area of mediumlow yield farmland was reduced from 291 250.13 hm^2 in 1985 to 76 489.87 hm^2 in 2010, coming down 74%. In Tianjin, the area of medium-low yield farmland of 2010 accounted for 19% of the total farmland, of which the ratios of medium-low yield farmland of Jinghai County, Jixian County, Dagang district of Binghai New Area, Wuqing District, Baodi District and Ninghe County were 43.12%, 18.59%, 17.23%, 14.01%, 7.05% and 0, respectively. Low soil nutrient content, drought and water shortage, as well as soil salinization were the main yield limiting factors to mediumlow yield farmland in Tianjin in 2010. [Conclusion] The countermeasures to improve the medium-low yield farmland were proposed, involving enhancing the investment of the government, strengthening the construction of water conservancy infrastructure, further improving the soil fertility, as well as saline and alkaline land, optimizing the farming system and planting drought and salt tolerance crops, etc. 展开更多
关键词 Medium-low yield farmland spatial-temporal distribution Limiting factors TIANJIN
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A Review of the "Alienation" Theme in Bernard Malamud's Works
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作者 路潇潇 《英语广场(学术研究)》 2012年第6期5-6,共2页
In Bernard Malamud's works,the theme of alienation occurs repeatedly.This article tries to make a review of the "alienation" theme in Malamud's four novels,Dubin's Lives,A New Life,The Tenants,an... In Bernard Malamud's works,the theme of alienation occurs repeatedly.This article tries to make a review of the "alienation" theme in Malamud's four novels,Dubin's Lives,A New Life,The Tenants,and The Fixer. 展开更多
关键词 alienation Dubin’s Lives A New Life The Tenants The Fixer
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Spatial-temporal Evolution and Driving Force of Cultivated Land Quality in Henan Province
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作者 宋艳华 《Agricultural Science & Technology》 CAS 2017年第11期2106-2112,2126,共8页
The purpose of this study was to find out the spatial-temporal rules and driving force of cultivated land quality in Henan Province in the last ten years. Agricultural land grading factor evaluation was used to evalua... The purpose of this study was to find out the spatial-temporal rules and driving force of cultivated land quality in Henan Province in the last ten years. Agricultural land grading factor evaluation was used to evaluate the cultivated land quality of 2002 and 2012 in Henan Province, and to research the change laws. Method of correlation coefficient was employed to select the driving forces affecting cultivated land quality evolution. The results indicated that the cultivated land quality in Henan Province increased slightly in the last ten years in general, and in spatial there were unchanged regions, increased regions and decreased regions. The cultivated land quality in spatial presented the trend of good becoming better, bad becoming worse, which should be highly valued in cultivated land quality protection and management. Land development and consolidation projects had significant contributions to increasing the cultivated land quality. Driving forces between the sudden change regions and gradual change regions were significantly different. The paper concluded that the research on the spatial-temporal evolution and driving force of cultivated land quality based on cultivated land quality evolution had important academic significance and practical value. 展开更多
关键词 Cultivated land quality spatial-temporal evolution Driving force Sudden change region Gradual change region Henan Province
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On Adaptation and Alienation in Translation
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作者 周小惠 《海外英语》 2014年第22期173-174,共2页
From cultural point of view,there are two methods in translation:adaptation which is TL culture-oriented and alienation which is SL culture-oriented.What this article tries to prove is that each of them has its own st... From cultural point of view,there are two methods in translation:adaptation which is TL culture-oriented and alienation which is SL culture-oriented.What this article tries to prove is that each of them has its own strong and weak points,which leads to the conclusion that both methods are justified in their existence.And last,some points for attention are suggested for translation,which include the relationship between SL and TL,the type of texts and the translator's purpose. 展开更多
关键词 ADAPTATION alienation TL SL
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The Alienation and Loneliness in Orpheus Descending
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作者 陈瑶琼 《海外英语》 2016年第23期164-165,共2页
Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangem... Orpheus Descending is written by American famous playwright Tennessee Williams. According to the portrayal of a series marginalized people, this drama presents the solitude in human beings' heart and the estrangement in interpersonal relations. This paper tries to analyze the solitude theme in this drama from philosophic aspect and realistic aspect, combining alienation theory and existentialism theory to analyze the reason and the manifestation of solitude. 展开更多
关键词 alienation LONELINESS Orpheus Descending
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Spatial-temporal Patterns and Driving Forces of Water Retention Service in China 被引量:14
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作者 XIAO Yang OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2019年第1期100-111,共12页
Overwhelming water-deficiency conditions and an unbalanced water supply and demand have been major concerns of both the Chinese government and the general public during recent decades. Studying the spatial-temporal pa... Overwhelming water-deficiency conditions and an unbalanced water supply and demand have been major concerns of both the Chinese government and the general public during recent decades. Studying the spatial-temporal patterns and impact factors that influence water retention in China is important to enhance the management of water resources in China and other similar countries. We employed a revised Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST) model and regression analyses to investigate the water retention service in China. The results showed that the southeastern China generally performed much better than Northwest China in terms of the spatial distribution of water retention. In general, the efficacy of the water retention service in China increased from 2000 to 2014; although some areas still had a downward trend. Water retention service increased significantly(P < 0.05) in aggregate in the Qinghai-Tibet Plateau, and the Da Hinggan Mountains and Xiao Hinggan Mountains. However, the service in southwestern China showed a decreasing trend(P < 0.05), which would have significant negative impact on the downstream population. This study also showed that in China the changes in water retention service were primarily due to climate change(which could explain 83.49% of the total variance), with anthropogenic impact as a secondary influence(likewise the ecological programs and socioeconomic development could explain 9.47% and 1.06%, respectively). Moreover, the identification of water retention importance indicated that important areas conservation and selection based on downstream beneficiaries is vital for optimization protection of ecosystem services, and has practical significance for natural resources and ecosystem management. 展开更多
关键词 WATER RETENTION spatial-temporal pattems driving FACTORS China
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