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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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Constructing, Mapping, and Analyzing Global Urban Forest Databases Using Hyperlinks: A World of Vast Unevenness and Research Challenges
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作者 Stanley D. Brunn Olena Dronova Mahmuda Sharmin 《Natural Resources》 2025年第1期1-23,共23页
A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking an... A distinctive feature of scholarly communities today is exploring topics and concepts in interdisciplinary and international contexts. This observation is increasingly apparent and visible in advancing our thinking and policies related to human/environmental worlds at local, regional, and global scales. Maps are an important part of these innovative and ongoing research approaches. In this context, we consider urban forests a topic meriting more attention of scholars studying the geographic and environmental intersections of the natural sciences with the social sciences and humanities. We construct two innovative knowledge bases, one a conceptual framework based on major themes and concepts related to mapping urban forests using key words of the first 100 results of a Google Scholar query and a second using the number of Google Scholar hyperlinks about mapping urban forests in 244 capital cities. We discovered that the constructed world maps reveal vast global unevenness in our knowledge about urban forests in hyperlink numbers and ratios, results that merit further attention by disciplinary, international and interdisciplinary scholarly communities. 展开更多
关键词 Urban Forests database MAPPING Google Scholar HYPERLINKS DISPARITIES Unevenness
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Concept of characteristics database alliance building:a case study of marine characteristic databases
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作者 ZHOU Li DONG Wenjing YANG Yi 《Marine Science Bulletin》 2025年第1期84-96,共13页
The characteristic databases in China face issues such as narrow resource coverage,low levels of standardization and normalization,and limited data sharing.To address these challenges,this paper proposes the concept o... The characteristic databases in China face issues such as narrow resource coverage,low levels of standardization and normalization,and limited data sharing.To address these challenges,this paper proposes the concept of characteristic databases alliance,using marine characteristic databases as a case for feasibility analysis and discussion.The paper outlines the development path for such alliances and offers recommendations for future growth,aiming to establish a collaborative platform for the development of characteristic databases. 展开更多
关键词 characteristic databases characteristic resources resource construction database alliance
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Best practice for developing integrative Chinese-Western medicine databases using electronic health records
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作者 REN Yan JIA Yulong +7 位作者 LIANG Wengxue XU Ye LIU Xuehong XIONG Yiquan JIANG Hao ZOU Kang SUN Xin TAN Jing 《World Journal of Integrated Traditional and Western Medicine》 2025年第3期174-186,共13页
Objectives:Electronic health records(EHRs)offer valuable real-world data(RWD)for Chinese medicine research.However,significant methodological challenges remain in developing integrative Chinese-Western medicine(ICWM)d... Objectives:Electronic health records(EHRs)offer valuable real-world data(RWD)for Chinese medicine research.However,significant methodological challenges remain in developing integrative Chinese-Western medicine(ICWM)databases.This study aims to establish a best-practice methodological framework,referred to as BRIDGE,to guide the construction of ICWM databases using EHRs.Methods:We developed the methodological framework through a comprehensive process,including systematic literature review,synthesis of empirical experiences,thematic expert discussions,and consultation with an external panel to reach consensus.Results:The BRIDGE framework outlines 6 core components for ICWM-EHR database development:Overall design,database architecture,data extraction and linkage,data governance,data verification,and data quality evaluation.Key data elements include variables related to study population,treatment or exposure,outcomes,and confounders.These databases support various research applications,particularly in evaluating the effectiveness and safety of integrative therapies.To demonstrate its practical value,we developed an ICWM-EHR database on women’s reproductive lifespan,encompassing 2,064,482 patients.This database captures women’s health conditions across the life course,from reproductive age to older adulthood.Conclusions:The BRIDGE methodological framework provides a standardized approach to building high-quality ICWM-EHR databases.It offers a unique opportunity to strengthen the methodological rigor and real-world relevance of Chinese medicine research in integrated healthcare settings. 展开更多
关键词 Chinese-Western medicine database Electronic health records Methodological framework database development Women’s reproductive health database
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About the Databases of Meteorological and Environmental Research
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《Meteorological and Environmental Research》 2025年第1期5-5,共1页
The journal of Meteorological and Environmental Research[ISSN:2152-3940]has been included and stored by the following famous databases:CA,CABI,CSA,EBSCO,UPD,AGRIS,EA,Chinese Science and Technology Periodical Database,... The journal of Meteorological and Environmental Research[ISSN:2152-3940]has been included and stored by the following famous databases:CA,CABI,CSA,EBSCO,UPD,AGRIS,EA,Chinese Science and Technology Periodical Database,and CNKI,as well as Library of Congress,United States. 展开更多
关键词 ISSN Library Congress meteorological environmental research issn environmental research scientific databases United States meteorological research databases
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About the Databases of Meteorological and Environmental Research
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《Meteorological and Environmental Research》 2025年第3期56-56,共1页
The journal of Meteorological and Environmental Research[ISSN:2152-3940]has been included and stored by the following famous databases:CA,CABI,CSA,EBSCO,UPD,AGRIS,EA,Chinese Science and Technology Periodical Database,... The journal of Meteorological and Environmental Research[ISSN:2152-3940]has been included and stored by the following famous databases:CA,CABI,CSA,EBSCO,UPD,AGRIS,EA,Chinese Science and Technology Periodical Database,and CNKI,as well as Library of Congress,United States. 展开更多
关键词 ISSN Library Congress meteorological environmental research issn environmental research scientific databases United States meteorological research databases
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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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GREEK EPIGRAPHIC DATABASES:SCOPE,STRUCTURE,AND PRACTICAL USE
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作者 Péter Kató 《Journal of Ancient Civilizations》 2025年第2期155-164,248,共11页
This paper explores the evolving landscape of digital resources in Greek epigraphy.A selection of digital projects is examined for its structure,accessibility,and scholarly utility,with a critical focus on completenes... This paper explores the evolving landscape of digital resources in Greek epigraphy.A selection of digital projects is examined for its structure,accessibility,and scholarly utility,with a critical focus on completeness,editorial policy,and economic sustainability.The analysis reveals tensions between openaccess ideals and the realities of commercial publishing,as well as challenges posed by short-term funding and limited project scopes.The paper also considers the integration of artificial intelligence tools,notably Ithaca,assessing their potential and current limitations.Emphasis is placed on the pedagogical impact of digital resources,showing how they empower a new generation of students and democratize access to source material.Ultimately,the study underscores the necessity of balancing innovation with scholarly rigor,advocating for ongoing critical reflection to ensure the meaningful development of digital epigraphy in both research and education. 展开更多
关键词 EPIGRAPHY databases academic research PUBLISHING DEMOCRATIZATION
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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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From Data to Discovery:How AI-Driven Materials Databases Are Reshaping Research
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作者 Yaping Qi Weijie Yang 《Computers, Materials & Continua》 2025年第5期1555-1559,共5页
AI-driven materials databases are transforming research by integrating experimental and computational data to enhance discovery and optimization.Platforms such as Digital Catalysis Platform(DigCat)and Dynamic Database... AI-driven materials databases are transforming research by integrating experimental and computational data to enhance discovery and optimization.Platforms such as Digital Catalysis Platform(DigCat)and Dynamic Database of Solid-State Electrolyte(DDSE)demonstrate how machine learning and predictive modeling can improve catalyst and solid-state electrolyte development.These databases facilitate data standardization,high-throughput screening,and cross-disciplinary collaboration,addressing key challenges in materials informatics.As AI techniques advance,materials databases are expected to play an increasingly vital role in accelerating research and innovation. 展开更多
关键词 DATA-DRIVEN materials database AI assistant materials design
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Pelvic Floor Dysfunction Databases:Evolution,Current Landscape,and Future Development
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作者 Jing-Yu Zhang An-Ran Wang +3 位作者 Shuo Liang Hong-Hui Shi Lan Zhu Si-Zhu Wu 《Chinese Medical Sciences Journal》 2025年第4期295-308,I0004,共15页
Pelvic floor dysfunction(PFD),including conditions such as stress urinary incontinence,pelvic organ prolapse,and fecal incontinence,significantly affects women's quality of life and their physical and mental healt... Pelvic floor dysfunction(PFD),including conditions such as stress urinary incontinence,pelvic organ prolapse,and fecal incontinence,significantly affects women's quality of life and their physical and mental health.With advancement of digital medicine,the systematic collection of data and the high-quality development of database platforms have increasingly become central pillars of PFD research and management.We systematically review the developmental stages of PFDrelated databases.We then conduct a comparative analysis of representative international and domestic platforms,examining key aspects including organizational structures and construction models,data sources and integration strategies,core functionalities,data quality control and standardization,data security and access management,and research applications.Finally,based on the current status of PFD database development both globally and in China,we offer recommendations to strengthen data infrastructure and guide future directions.The findings may serve as a valuable reference for the optimization of PFD databases worldwide. 展开更多
关键词 pelvic floor dysfunction disease registry databasE data platform disease research
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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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Corrigendum to“Meta databases of steel frame buildings for surrogate modelling and machine learning-based feature importance analysis”[Journal of Resilient Cities and Structures Volume 3 Issue 1(2024)20-43]
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作者 Delbaz Samadian Jawad Fayaz +2 位作者 Imrose B.Muhit Annalisa Occhipinti Nashwan Dawood 《Resilient Cities and Structures》 2025年第1期124-124,共1页
The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significan... The authors regret that the original publication of this paper did not include Jawad Fayaz as a co-author.After further discussions and a thorough review of the research contributions,it was agreed that his significant contributions to the foundational aspects of the research warranted recognition,and he has now been added as a co-author. 展开更多
关键词 machine learning meta databases jawad fayaz surrogate modelling feature importance analysis steel frame buildings
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International Renowned Databases and Institutions Indexing Asian Agricultural Research
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《Asian Agricultural Research》 2025年第12期52-52,共1页
Asian Agricultural Research(ISSN1943-9903),founded in 2009,is a monthly comprehensive agricultural academic journal published and approved by the Library of Congress of the United States of America.
关键词 Library Congress INDEXING international renowned databases monthly publication agricultural academic journal Asian agricultural research United States America
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Analysis of a dverse drug reactions a ssociated with ceftazidime/a vibactam using the FAERS database
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作者 Qiu-Lan Mo Juan-Juan Xie +1 位作者 Rong-Hui Wang Qiu-Gui Wei 《Medical Data Mining》 2026年第1期3-12,共10页
Background:The purpose of this study was to analyze and classify adverse drug events(ADEs)related to ceftazidime/avibactam reported in the Food and Drug Administration Adverse Event Reporting System(FAERS)database and... Background:The purpose of this study was to analyze and classify adverse drug events(ADEs)related to ceftazidime/avibactam reported in the Food and Drug Administration Adverse Event Reporting System(FAERS)database and to evaluate their potential safety signals since the drug’s market introduction.Methods:This analysis systematically extracted and filtered FAERS data for ceftazidime/avibactam from its market launch in 2015 to the last quarter of 2024,utilizing the Medical Dictionary for Regulatory Activities(MedDRA)terminology for ADE recoding.The analysis employed the reporting odds ratio(ROR)method to assess the strength of ADE signals and to identify significant diseases associated with infections,the hepatobiliary system,the urinary system,and the nervous system.Results:A review of 540 adverse reaction reports revealed significant signals of adverse effects related to infections,hepatobiliary disorders,urinary system issues,and neurological impairments,including pathogen resistance,liver and kidney function impairment,encephalopathy,thrombocytopenia,and toxic epidermal necrolysis.However,these issues require further clinical attention.Conclusion:Ceftazidime/avibactam is associated with a range of adverse reactions,necessitating enhanced clinical monitoring,particularly in patients with underlying liver or kidney dysfunction.Continuous risk assessment and vigilant monitoring are critical for its clinical use.However,this study is limited by inherent reporting biases and confounders associated with the spontaneous reporting database(FAERS).Future research should validate these signals through prospective cohort and mechanistic studies and explore personalized risk management strategies for high-risk populations. 展开更多
关键词 ceftazidime/avibactam FAERS database adverse drug event
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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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WEIGHTED ALGORITHM FOR FINGERPRINTING RELATIONAL DATABASES 被引量:1
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作者 崔新春 秦小麟 +1 位作者 管致锦 束瑜 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期148-154,共7页
The necessity and the feasibility of introducing attribute weight into digital fingerprinting system are given. The weighted algorithm for fingerprinting relational databases of traitor tracing is proposed. Higher wei... The necessity and the feasibility of introducing attribute weight into digital fingerprinting system are given. The weighted algorithm for fingerprinting relational databases of traitor tracing is proposed. Higher weights are assigned to more significant attributes, so important attributes are more frequently fingerprinted than other ones. Finally, the robustness of the proposed algorithm, such as performance against collusion attacks, is analyzed. Experimental results prove the superiority of the algorithm. 展开更多
关键词 digital fingerprinting relational database systems copyright protection attribute weight traitor tracing
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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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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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