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Spatio-temporal Evaluation of Multi-scale Cultivated Land System Resilience in Black Soil Region from 2000 to 2019:A Case Study of Liaoning Province,Northeast China
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作者 WANG Yue JIANG Yuting ZHU Guoxu 《Chinese Geographical Science》 SCIE CSCD 2024年第1期168-180,共13页
It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cult... It is of great significance to systematically analyze the cultivated land system resilience(CLSR) for the black soil protection and national food security.The CLSR is impacted by planting structure adjustment and cultivated land quality decline,posing major hidden dangers to food security.It is urgent to evaluate the CLSR at multiple spatio-temporal scales.This study took Liaoning Province in the black soil region of Northeast China as an example.Based on the resilience theory,this study constructed the CLSR evaluation system from the input-feedback perspective at the provincial-scale and the city-scale,and used the rank-sum ratio comprehensive evaluation method(RSR) to analyze the key influencing factors of CLSR in Liaoning Province and its 14 cities from 2000 to 2019.The results showed that:1) the time series changes of CLSR at the provincial-scale and the city-scale in Liaoning Province were similar,both showing an increasing trend.2) The CLSR in Liaoning Province presented a spatial pattern of ‘high in the west and low in the east’ at the city-scale.3) There were seven and six main influencing factors of CLSR at the provincial-scale and the city-scale,respectively.In addition to the net income per capita of rural households,other influencing factors of CLSR were different at the provincial-scale and the city-scale.The feedback factors were dominant at the provincial-scale,and the input factors and feedback factors were dominant at the city-scale.The results could provide a reference for the utilization of black soil and draw on the experience of regional agricultural planning and adjustment. 展开更多
关键词 cultivated land system resilience(CLSR) rank-sum ratio comprehensive evaluation(RSR) multi-scales influencing factors black soil region Liaoning Province China
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Evaluation on the Influencing Factors of Agricultural Land Productivity in Huang-Huai Plain,China
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作者 SONG Yan-hua WANG Guo-qiang 《Asian Agricultural Research》 2010年第8期58-60,64,共4页
Taking Huang-Huai Plain as an example,evaluation index system is established from four aspects,including the resources condition,the social and economic condition,the agricultural science and technology condition,and ... Taking Huang-Huai Plain as an example,evaluation index system is established from four aspects,including the resources condition,the social and economic condition,the agricultural science and technology condition,and the disaster resistant and sustainable production condition.Correlation coefficient method and expert consultation method are used to determine the weight of evaluation index.After the standardization of extreme value,weighted sum method and multiple regression method are adopted to evaluate the influencing factors of agricultural land productivity in Huang-Huai Plain,China.Evaluation result shows that agricultural science and technology condition has a lower contribution rate to the productivity of Huang-Huai Plain than that to Henan Province.Resources condition has a higher contribution rate to the productivity of Huang-Huai Plain than that to Henan Province.Both the social and economic condition and the disaster control and sustainable production condition show relatively small contribution rate to the productivity of Huang-Huai Plain.It can be concluded that the main factors affecting the productivity of Huang-Huai Plain are the backward agricultural science and technology level,the poor farmland quality and the farmland infrastructure.Based on this,relevant suggestions are put forward to improve the farmland productivity of Huang-Huai Plain. 展开更多
关键词 Huang-Huai Plain Agricultural land productivity influencing factor evaluation index system China
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Study on Characteristics and Influencing Factors of Coagulation Indexes in Pulmonary Infection Sepsis
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作者 Pan Wei Xuanguo Zhang 《Journal of Clinical and Nursing Research》 2022年第1期122-125,共4页
Objective:To explore the characteristics and influencing factors of coagulation indexes in patients with pulmonary infection sepsis.Methods:104 patients in Shaanxi Provincial Hospital of Chinese Medicine from January ... Objective:To explore the characteristics and influencing factors of coagulation indexes in patients with pulmonary infection sepsis.Methods:104 patients in Shaanxi Provincial Hospital of Chinese Medicine from January 2015 to April 2021 were collected and divided into case group(52 cases)and control group(52 cases).The general data and coagulation indexes of the two groups were statistically analyzed.The difference was statistically significant(P<0.05).Binary logistic regression analysis was used.Results:The indexes of age PT,APTT,TT,FDP,D-Dimer,INR and PLT in the control group were significantly higher than those in the control group(P<0.05);There was no significant difference in FIB-C(P>0.05);Binary logistic regression analysis showed that D-Dimer and PLT were the risk factors of pulmonary infection sepsis(OR>1,P<0.05).Conclusion:FDP and D-Dimer are risk factors for the development of pneumonia into sepsis. 展开更多
关键词 SEPSIS Pulmonary infection Coagulation index influencing factors
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An empirical study on evaluation indexes of scientific research achievements in nursing 被引量:5
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作者 Jin-Lian Cheng Xi Tan 《Frontiers of Nursing》 CAS 2018年第1期35-41,共7页
Objective: The purpose of this empirical study was to investigate the evaluation indexes of nursing research results and to provide references for the optimization of nursing research results and their clinical applic... Objective: The purpose of this empirical study was to investigate the evaluation indexes of nursing research results and to provide references for the optimization of nursing research results and their clinical applications.Methods: A total of 150 clinical nursing studies were randomly selected, the clinical applications of their results were investigated,and the results were evaluated using the evaluation indexes of nursing research achievements.Results: The results of 101 clinical nursing studies were promoted through their application, accounting for 82.79%, but they were mostly promoted and applied in small areas. When the evaluation indexes of nursing research results were used to evaluate the results, the scores for the applied results were higher than those of unapplied results, and the difference was statistically significant(P < 0.05). Considering the levels of the results, the scores of the results of studies at the national level were higher than those of studies at the municipal and hospital levels; the scores of the results of studies at the provincial level were higher than those at the hospital level; and the scores of the results of originally innovative studies were higher than those of partially innovative studies. The differences were statistically significant(P < 0.05). In terms of overall scores, the scores of the results at the provincial level were higher than those at the hospital level, and the difference was statistically significant(P < 0.05).Conclusions: The evaluation indexes of nursing research results in this study can scientifically and effectively evaluate the level,value, and effectiveness of the nursing research results and can promote the clinical application of the optimized results. 展开更多
关键词 NURSING CLINICAL study results evaluation index PROMOTION by application influencing factors
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Gas storage in shale pore system:A review of the mechanism,control and assessment
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作者 Yue Feng Xian-Ming Xiao +3 位作者 En-Ze Wang Ping Gao Chen-Gang Lu Gang Li 《Petroleum Science》 SCIE EI CSCD 2023年第5期2605-2636,共32页
In the past 15 years,the shale gas revolution and large-scale commercial developments in the United States have driven the exploration and development of shale plays worldwide.Among many factors affecting shale gas ex... In the past 15 years,the shale gas revolution and large-scale commercial developments in the United States have driven the exploration and development of shale plays worldwide.Among many factors affecting shale gas exploration potential,the gas-bearing properties of shale(quantity,storage state,composition)and their controlling factors are the essential research attracting wide attention in the academic community.This paper reviews the research progress on the retention mechanism,influencing factors,and evaluation methods for resource potential of the shale gas system,and proposes further research directions.Sorption is the main mechanism of gas retention in organic-rich shales;the gas is mainly stored in nanopores of shale in free and sorption states.The presence of water and nonhydrocarbon gases in pores can complicate the process and mechanism of methane(CH4)sorption,and the related theoretical models still need further development.The in-situ gas content and gasbearing properties of shale are governed by the geological properties(organic matter abundance,kerogen type,thermal maturity,mineral composition,diagenesis),the properties of fluids in pores(water,CH_(4),non-hydrocarbon gases),and geological conditions(temperature,pressure,preservation conditions)of the shale itself.For a particular basin or block,it is still challenging to define the main controlling factors,screen favorable exploration areas,and locate sweet spots.Compared to marine shales with extensive research and exploration data,lacustrine and marine-continental transitional shales are a further expanding area of investigation.Various methods have been developed to quantitatively characterize the in-situ gas content of shales,but all these methods have their own limitations,and more in-depth studies are needed to accurately evaluate and predict the in-situ gas content of shales,especially shales at deep depth. 展开更多
关键词 Shale gas Retention mechanism Multi-component adsorption influencing factors evaluation method
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耦合DWT-IFLOF的大坝监测数据异常检测算法
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作者 王译羚 丁勇 李登华 《中国农村水利水电》 北大核心 2024年第7期203-209,共7页
基于数据驱动的模型已广泛应用于大坝运行状态建模与短期变形预测等领域中,而监测数据中存在的异常值会削弱甚至破坏数据驱动模型的可信度和鲁棒性。针对上述问题,提出一种耦合DWT-IFLOF的大坝监测数据异常检测算法。首先,采用小波降噪... 基于数据驱动的模型已广泛应用于大坝运行状态建模与短期变形预测等领域中,而监测数据中存在的异常值会削弱甚至破坏数据驱动模型的可信度和鲁棒性。针对上述问题,提出一种耦合DWT-IFLOF的大坝监测数据异常检测算法。首先,采用小波降噪技术减少监测数据集中采集噪声对模型建模的负面干扰。其次设计一种耦合孤立森林(iForest)异常检测算法与归一化局部离群因子值(LOF_(nor))的全新监测数据异常度量化表达式。最后通过引入拉伊达准则,依据计算得到的异常分数,对异常值进行定性筛查。试验结果表明,相较于热门异常检测算法,在查全率层面提升18.32%以上;查准率提升20.14%以上;准确率提升0.71%以上。可针对大坝安全监测数据中的异常值进行有效检测。 展开更多
关键词 异常检测 孤立森林 局部离群因子 评价指标
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Influencing Factors of Total Factor Energy Efficiency in Bohai Rim Region Based on DEA-Tobit Model 被引量:1
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作者 Weifeng Gong Xiaohong Qi +2 位作者 ChuanhuiWang Wenwen Li Yang Xu 《Energy Engineering》 EI 2022年第4期1663-1679,共17页
Bohai Rim region is an important economic development area and a large carbon emission area in China.It is of great significance to explore the total factor energy efficiency and its influencing factors for the low ca... Bohai Rim region is an important economic development area and a large carbon emission area in China.It is of great significance to explore the total factor energy efficiency and its influencing factors for the low carbon transformation and high-quality development of the Bohai Rim region.Based on the total factor energy efficiency framework,the DDF-DEA model was used to calculate the total factor energy efficiency,and the internal and external differences of the total factor energy efficiency were further analyzed.The internal and external influencing factors were determined by ML index method and classical endogenous growth theory,and then the Tobit panel model was used to empirically analyze the action mechanism of all influencing factors of total factor energy efficiency in the Bohai Rim region.The results show that the pure technical efficiency,scale efficiency and technological progress among the internal influencing factors contribute to the improvement of energy efficiency in the Bohai Rim region.Industrial structure,industrial internal structure and ownership structure inhibit the improvement of energy efficiency.Energy consumption structure and energy endowment also have a negative impact on energy efficiency.Therefore,measures such as promoting technological progress,adjusting economic structure and optimizing energy structure will effectively improve total factor energy efficiency in the Bohai Rim region. 展开更多
关键词 Total factor energy efficiency influencing factors Bohai Rim region DEA-Tobit model ML index method
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Research on China's Aquaculture Efficiency Evaluation and Influencing Factors with Undesirable Outputs 被引量:2
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作者 JI Jianyue WANG Pingping 《Journal of Ocean University of China》 SCIE CAS 2015年第3期569-574,共6页
Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable output variable,... Taking the aquaculture area, the number of farming boats and that of aquaculturist as input variables, the aquaculture production as desirable output variable and polluted economic loss as undesirable output variable, this paper conducts SBM model to evaluate the aquaculture efficiency based on the data of 16 aquaculture-developed provinces in China from 2004 to 2011. The results show the efficiency in China has not changed much in recent years with the efficiency values mainly between 0.39 and 0.53, and the efficiency of marine-aquaculture-dominated provinces is generally higher than that of freshwater-aquaculture-dominated ones. To analyze the difference under the efficiency, the panel Tobit model is used with education level factor, training factor, technology extension factor, technical level factor, scale factor and species factor as the efficiency influencing factors. The results show that technology extension factor and technical level factor have significant positive influence. 展开更多
关键词 水产养殖业 养殖效率 影响因素 中国 期望 技术推广 评价 输出变量
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Extreme gradient boosting algorithm based urban daily traffic index prediction model:a case study of Beijing,China
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作者 Jiancheng Weng Kai Feng +2 位作者 Yu Fu Jingjing Wang Lizeng Mao 《Digital Transportation and Safety》 2023年第3期220-228,共9页
The exhaust emissions and frequent traffic incidents caused by traffic congestion have affected the operation and development of urban transport systems.Monitoring and accurately forecasting urban traffic operation is... The exhaust emissions and frequent traffic incidents caused by traffic congestion have affected the operation and development of urban transport systems.Monitoring and accurately forecasting urban traffic operation is a critical task to formulate pertinent strategies to alleviate traffic congestion.Compared with traditional short-time traffic prediction,this study proposes a machine learning algorithm-based traffic forecasting model for daily-level peak hour traffic operation status prediction by using abundant historical data of urban traffic performance index(TPI).The study also constructed a multi-dimensional influencing factor set to further investigate the relationship between different factors on the quality of road network operation,including day of week,time period,public holiday,car usage restriction policy,special events,etc.Based on long-term historical TPI data,this research proposed a daily dimensional road network TPI prediction model by using an extreme gradient boosting algorithm(XGBoost).The model validation results show that the model prediction accuracy can reach higher than 90%.Compared with other prediction models,including Bayesian Ridge,Linear Regression,ElatsicNet,SVR,the XGBoost model has a better performance,and proves its superiority in large high-dimensional data sets.The daily dimensional prediction model proposed in this paper has an important application value for predicting traffic status and improving the operation quality of urban road networks. 展开更多
关键词 Traffic prediction Traffic performance index(TPI) influencing factor XGBOOST Machine learning model
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Factors influencing the quality of rural human settlements in a peripheral metropolitan area based on a structural equation model:A case study from Beijing
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作者 Kan Zhou 《Chinese Journal of Population,Resources and Environment》 2014年第4期301-308,共8页
Rural human settlement is a significant indicator of the living standards of rural residents,and its improvement can contribute to promoting the positive interaction between inhabited environment and the social,econom... Rural human settlement is a significant indicator of the living standards of rural residents,and its improvement can contribute to promoting the positive interaction between inhabited environment and the social,economic,and resource environment in the countryside.Based on 557 valid questionnaires of satisfaction evaluation of human settlement in the peripheral metropolitan area of Beijing,this paper analyzed the elemental characteristics and factors influencing human settlement quality using multivariate statistical analysis and a structural equation model.The result shows that,first,the rural residents in a peripheral metropolitan area of Beijing are generally satisfied with the quality of human settlement(satisfaction rate is 66.2%).Specifically,the natural and social environment of the countryside is excellent and harmonious and corresponding standard of countryside infrastructure is advanced,but the quality of public services and follow-up management of facilities are in urgent need of improvement and the imbalance between revenue and expenditure of rural households has led to a continuous increase in the pressures of life.Second,factors such as social atmosphere,appearance of the village,entertainment,living costs,fundamental public services,and production costs have significant effects on human settlement quality in this peripheral metropolitan area,with social atmosphere as the main one.Living costs and supporting services are the main constraints to improvement in the quality of human settlement. 展开更多
关键词 human SETTLEMENTS SATISFACTION evaluation influencing factors structural EQUATION model BEIJING
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Comparison of evaluation indexes for Gastroenterology and Hepatology journals in different databases
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作者 Jia-Yuan Li Zhi-Han Yan +2 位作者 Ze Xiang Ce Gao Jian Wu 《World Journal of Gastroenterology》 SCIE CAS 2022年第38期5648-5657,共10页
BACKGROUND Accurate assessment of the quality of academic journals is of great significance.While Journal Impact Factor(JIF),calculated by Clarivate and based upon the Web of Science literature database,and CiteScore(... BACKGROUND Accurate assessment of the quality of academic journals is of great significance.While Journal Impact Factor(JIF),calculated by Clarivate and based upon the Web of Science literature database,and CiteScore(CS),developed by Elseiver and based upon the Scopus database,have enjoyed high uptake worldwide,efforts continue towards creation of other scientometric indexes that will provide evergreater qualitative insights into journal impact.Such efforts have yielded the newly-launched Journal Article Influence Index(JAII),which is based on the Reference Citation Analysis(RCA)database,an open multidisciplinary citation analysis database based on artificial intelligence technology.AIM To evaluate and summarize the similarities and differences between JAII and JIF/CS as journal evaluation indicators,and provide an intuitive method for visual representation of the related data.METHODS We searched the Journal Citation Reports to obtain the 2021 JIF list,downloaded the CS list updated in July on the Scopus website,and collected the comprehensive list of 2022 JAIIs from the RCA database(www.referencecitationanalysis.com).RESULTS Our research results revealed that by breaking through the time limit of mainstream journalevaluation methods, the JAII is able to perform well in data reliability, establishing its benefit as acomplementary scientometric index to JIF and CS.CONCLUSIONJAII provides comprehensive assessment of the quality and performance of journals. 展开更多
关键词 Journal Article Influence index Journal Impact Factor CiteScore Gastroenterology and Hepatology Scientometric index
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Carbon Emission Trends of Manufacturing and Influencing Factors in Jilin Province,China
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作者 YU Chao MA Yanji 《Chinese Geographical Science》 SCIE CSCD 2016年第5期656-669,共14页
This paper constructed a carbon emission identity based on five factors: industrial activity, industrial structure, energy intensity, energy mix and carbon emission parameter, and analyzed manufacturing carbon emissio... This paper constructed a carbon emission identity based on five factors: industrial activity, industrial structure, energy intensity, energy mix and carbon emission parameter, and analyzed manufacturing carbon emission trends in Jilin Province at subdivided industrial level through Log-Mean Divisia Index(LMDI) method. Results showed that manufacturing carbon emissions of Jilin Province increased 1.304 × 107 t by 66% between 2004 and 2010. However, 2012 was a remarkable year in which carbon emissions decreased compared with 2011, the first fall since 2004. Industrial activity was the most important factor for the increase of carbon emissions, while energy intensity had the greatest impact on inhibiting carbon emission growth. Despite the impact of industrial structure on carbon emissions fluctuated, its overall trend inhibited carbon emission growth. Further, influences of industrial structure became gradually stronger and surpassed energy intensity in the period 2009–2010. These results conclude that reducing energy intensity is still the main way for carbon emission reduction in Jilin Province, but industrial structure can not be ignored and it has great potential. Based on the analyses, the way of manufacturing industrial structure adjustment for Jilin Province is put forward. 展开更多
关键词 碳排放强度 吉林省 制造业 发展趋势 影响因素 产业结构调整 能源强度 中国
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Performance Evaluation of Urban Comprehensive Carrying Capacity of Harbin, Heilongjiang Province in China 被引量:6
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作者 DIAO Shuo YUAN Jiadong WU Yanyan 《Chinese Geographical Science》 SCIE CSCD 2019年第4期579-590,共12页
Urban comprehensive carrying capacity is an important guarantee and external representation of regional sustainable development. Based on urban comprehensive carrying capacity, this paper constructed a performance eva... Urban comprehensive carrying capacity is an important guarantee and external representation of regional sustainable development. Based on urban comprehensive carrying capacity, this paper constructed a performance evaluation index system of urban comprehensive carrying capacity, and used entropy method, urban comprehensive carrying capacity measurement model and urban sustainable development model to measure spatial and temporal comprehensive carrying capacity of Harbin City in Heilongjiang Province from 2012 to 2017. The results show that: 1) index weight analysis suggested the regional development mode in Harbin still followed an epitaxial development mode, which pursued the expansion of scale and the growth of total amount of regional development, neglecting the effective utilization of resources and the improvement of structural benefits. 2) In the pressure system, the index of resource support has dropped sharply. The index of environmental capacity and social progress has risen circuitously, while the degree of agglomeration and the value of transportation facilities have risen steadily;in the pressure system, the index of population development and economic growth tended to fluctuate, while energy consumption and environmental pollution showed a more synchronous change in characteristics, and the livable demand remained at a high level. 3) The carrying capacity index of resources and environment in Harbin has been declining, and the acquired carrying capacity index fluctuated. The long-term regional development model has severely impaired the carrying capacity of resources and environment. 4) The comprehensive carrying capacity of Harbin has clear spatial differentiation characteristics. Finally, the paper proposes that location conditions, economic development level, government regulation, and science and technology are the main factors influencing the spatial differentiation of urban comprehensive carrying capacity. 展开更多
关键词 COMPREHENSIVE carrying capacity NATURAL carrying capacity performance evaluation influencing factors HARBIN CITY
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Quantification of driving factors on NDVI in oasis-desert ecotone using geographical detector method 被引量:4
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作者 ZHANG Yu ZHANG Ke-cun +1 位作者 AN Zhi-shan YU Yan-ping 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2615-2624,共10页
Within oasis-desert ecotone regions,the normalized difference vegetation index(NDVI)is an important parameter for evaluating the growth of vegetation.An accurate quantitative study between NDVI and environmental and a... Within oasis-desert ecotone regions,the normalized difference vegetation index(NDVI)is an important parameter for evaluating the growth of vegetation.An accurate quantitative study between NDVI and environmental and anthropogenic factors is critical for understand the driving factors of vegetation growth in oasis-desert ecotone.In 2016,four periods Landsat 8 OLI_TIRS images,relevant climatological parameters data(air temperature,air relative humidity,wind velocity and accumulated temperature),land cover type data and soil data were selected as proxies.In order to quantify the explanatory power for NDVI spatial and temporal distribution in the southern edge of Dunhuang City and northern side of the Mingsha Mountain,the geographical detector model was used to explain the potential influences of factors versus the spatial distribution of NDVI,and each explanatory variable's relative importance can be calculated.The factor detector results disclose that the spatial distribution of NDVI is primarily dominated by land cover type.The risk detector results show that,high NDVI region is located within woodland.The mean value of NDVI displays an increase and then decrease trend with air temperature increase.With the increase of wind velocity and decrease of air relative humidity,the NDVI value shows a decrease trend.The interactive q values between the two factors are higher than any q value of separated factors.Results also indicate that the strongest interactive effects of NDVI are different in distinct seasons.Consequently,anthropogenic activity is more important than environmental factors on NDVI in oasis-desert ecotone.We also demonstrate that air relative humidity rather than air temperature have played a greater role in NDVI spatial distribution. 展开更多
关键词 Influence factors Normalized DIFFERENCE VEGETATION index GEOGRAPHICAL DETECTOR Oasis-desert ECOTONE
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Sense Estimation and Instrumental Evaluation of Fabric-Evoked Prickle 被引量:1
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作者 敖利民 郁崇文 《Journal of Donghua University(English Edition)》 EI CAS 2004年第3期82-87,共6页
In this paper, the mechanism of fabric-evoked prickle is discussed, which indicates that the mechanical stimuli aroused by the fiber ends on the fabric surface to the skin-sensory receptors are responsible for prickle... In this paper, the mechanism of fabric-evoked prickle is discussed, which indicates that the mechanical stimuli aroused by the fiber ends on the fabric surface to the skin-sensory receptors are responsible for prickle. The factors influencing the intensity of prickle are specialized and anatomized. Several means of sense estimate, including the corresponding statistical measures, are described. A few groping objective methods of evaluating prickle are analyzed, including the testing principles, the advantages and the disadvantages. At last, a new concept is proposed on the objective evaluation of prickle. 展开更多
关键词 感官评价 仪器检验 织布诱发刺痛 服装舒适性 客观评价 主观评价 统计度量
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Evaluation and Overview of Progress in Farmland Protection Researches 被引量:2
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作者 Lan LUO Guo ZHANG +1 位作者 Yuerong ZHENG Xiang NING 《Asian Agricultural Research》 2013年第8期35-40,共6页
With rapid advance of urbanization in China,both quantity and quality of farmland are gravely threatened,human-land conflict is growing,and the issue of grain security becomes more serious.Accordingly,practical and fe... With rapid advance of urbanization in China,both quantity and quality of farmland are gravely threatened,human-land conflict is growing,and the issue of grain security becomes more serious.Accordingly,practical and feasible protection of farmland has become one of core problems in China's land resource management.From theory,system,effective factors and measures and methods of farmland protection, this paper comprehensively analyzes research achievement and progress in farmland protection,in the hope of providing basis for further indepth research of farmland protection in China. 展开更多
关键词 FARMLAND PROTECTION FARMLAND PROTECTION system Inf
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Evaluation of E-commerce Poverty Alleviation Effect in the Context of Rural Revitalization Strategy
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作者 Luming YANG Nan NAN Pianpian QIAN 《Asian Agricultural Research》 2019年第12期57-61,共5页
The industrial prosperity proposed in the overall requirement of rural revitalization strategy in the Report of the 19th National Congress is the cornerstone of rural development. E-commerce poverty alleviation is an ... The industrial prosperity proposed in the overall requirement of rural revitalization strategy in the Report of the 19th National Congress is the cornerstone of rural development. E-commerce poverty alleviation is an effective way of poverty alleviation in recent years. This paper mainly explored the factors influencing the rural e-commerce poverty alleviation and the evaluation of poverty alleviation effects,in order to come up with countermeasures and recommendations to provide assistance and guidance for the use of e-commerce to achieve poverty alleviation and accordingly to revitalize the rural industry. Firstly,using the literature research method,it proposed four level Ⅰ indicators influencing the e-commerce poverty alleviation,and designed a detailed level Ⅱ indicator system under each dimension. Then,the questionnaire survey method was employed to collect data for SPSS analysis to verify whether the designed indicator system is correct. Finally,it analyzed the problem of the current stage of e-commerce poverty alleviation by means of the quadrifid graph,and came up with corresponding countermeasures on the basis of the four key levek I factors. 展开更多
关键词 E-COMMERCE poverty alleviation RURAL REVITALIZATION influencing factors EFFECT evaluation Strategies
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Low temperature cracking behavior of asphalt binders and mixtures: A review
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作者 Meng Guo Xiupeng Yao Xiuli Du 《Journal of Road Engineering》 2023年第4期350-369,共20页
Low temperature cracking(LTC)distress on pavement seriously affects road life.This paper finished a literature review of the research on the mechanism of LTC of asphalt composites(asphalt composites refers to asphalt ... Low temperature cracking(LTC)distress on pavement seriously affects road life.This paper finished a literature review of the research on the mechanism of LTC of asphalt composites(asphalt composites refers to asphalt binder and asphalt mixture in this article),test methods,factors contributing to LTC,measures to prevent and control the distress,and prediction of LTC in asphalt pavements.The following conclusions were obtained:the cracking mechanism of asphalt mixtures needs to be further revealed by means of simulation at the micro level,the BBR and 4 mm plate test(by DSR)methods are currently optimal,and a correlation between asphalt and asphalt mixture evaluation indexes needs to be established.Sensitivity analyses are needed for the factors affecting LTC of asphalt mixtures.It is necessary to calculate the contribution of each factor to the LTC of asphalt mixtures.The aim is to propose targeted improvement measures for the most unfavourable factors,as well as to carry out research and development of key materials for anti-cracking.Measures for the prevention and control of LTC of asphalt pavement are analyzed and discussed.Existing researches on the prediction of LTC of asphalt pavements is discussed.It is necessary to analyse the mechanical response of asphalt pavement,the damage process and the sensitivity of anti-cracking parameters on the basis of considering the complex geometrical characteristics and material properties of asphalt pavement materials.Finally,the mechanism of LTC,evaluation methods,factors influencing LTC,and remedial measures for asphalt composites were summarized,and future research prospects were suggested.This paper provides theoretical support for the further solution of LTC distress of asphalt pavement,which is effective on the improvement of pavement life. 展开更多
关键词 Asphalt pavement Low temperature cracking evaluation methods influencing factors Distress improvement measures
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基于网络分析的水网可达性评估 被引量:1
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作者 李发文 高菲 《水利水电技术(中英文)》 北大核心 2024年第3期127-139,共13页
【目的】为探究水资源可达性的空间格局,促进优化水资源配置,科学规划水系布局,【方法】提出一种基于网络特性和取水成本的水网可达性计算方法。运用网络分析工具sDNA计算网络可达性指标,以CRITIC法计算网络分析指标权重,加权求和得到... 【目的】为探究水资源可达性的空间格局,促进优化水资源配置,科学规划水系布局,【方法】提出一种基于网络特性和取水成本的水网可达性计算方法。运用网络分析工具sDNA计算网络可达性指标,以CRITIC法计算网络分析指标权重,加权求和得到水网网络可达性,然后通过核密度估计进行空间拓展;综合考虑地形、土地利用、道路因素,制作研究区的成本阻力栅格数据,水网网络可达性减去累计成本阻力,以此评估水网的可达性。【结果】研究区的平均可达性为0.31,标准差为0.04,变异系数为0.13。当河网是偏自然状态水系时,可达性呈现出树枝状分布,从主河道到支流逐渐减弱,且随着远离河道而减弱。在地形较为平坦、人类活动频繁、人工渠道发达的区域,一些江河交汇处将出现水网可达性较高的密集区域,例如汉江中游、长江中游、太湖流域、里下河流域、黄淮海平原、渭河平原。【结论】结果表明,从网络分析的角度出发,将水网视为一个拓扑网络来计算水网的可达性,实现了在大尺度区域的应用。同时考虑了取水成本和阻力对局部可达性的影响,从而增加了可达性结果的准确性,为实现精细化的水资源管理提供了重要的依据。 展开更多
关键词 水可达性评估 成本距离 核密度估计 影响因素
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融合Altmetrics指标的领域高产学者综合影响力研究——以Nature生物科技子刊为例 被引量:1
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作者 宋艳辉 魏新星 邱均平 《现代情报》 北大核心 2024年第1期153-167,共15页
[目的/意义]评估高产学者的影响力有利于推动学者研究的积极性,也可为引进优秀人才提供参考。根据普赖斯定律确定的高产作者是一个研究领域中有影响力的骨干力量,在科研工作中发挥着关键的导向作用。但依据科研产出量这一单一指标来评... [目的/意义]评估高产学者的影响力有利于推动学者研究的积极性,也可为引进优秀人才提供参考。根据普赖斯定律确定的高产作者是一个研究领域中有影响力的骨干力量,在科研工作中发挥着关键的导向作用。但依据科研产出量这一单一指标来评判学者的影响力存在一定的局限性。合理的学者影响力评价方法在评价学者科研产出绝对数量的基础上还应考虑科研成果的质量,对学者进行包括学术水平在内多维度的综合影响力展开评价研究。[方法/过程]本文在前人的研究基础上初步遴选传统指标和Altmetrics指标,以3本Nature生物科技子刊为例,其官网为数据源采集相关指标数据。分别从高产学者的科研影响力和社会影响力两个维度构建评价指标体系,通过相关性分析等方法对指标进行筛选,接着采用因子分析、主成分分析方法分别对高产学者的科研影响力和社会影响力进行评价,并分析两个维度的相关关系,最后得到高产学者影响力的二维测度结果。[结果/结论]结果显示,大部分学者在两个维度的影响力排名差距较大,并且两个维度呈较强的正相关关系,因此本文将科研影响力即传统指标与社会影响力即Altmetrics指标二者结合进行高产学者的综合影响力评价具有合理性。同时,通过比较该领域不同发文量的高产学者综合影响力情况,发现高产学者科研成果的“高产出量”并不完全意味着“高质量”,预示学者们应摒弃唯发文量至上的观念,形成一支真正高质量的高产作者队伍,助推领域的发展。 展开更多
关键词 高产学者 学者影响力 Altmetrics指标 评价指标
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