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Global Change in Agricultural Flash Drought over the 21st Century 被引量:1
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作者 Emily BLACK 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期209-220,I0002-I0019,共30页
Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop... Agricultural flash droughts are high-impact phenomena, characterized by rapid soil moisture dry down. The ensuing dry conditions can persist for weeks to months, with detrimental effects on natural ecosystems and crop cultivation. Increases in the frequency of these rare events in a future warmer climate would have significant societal impact. This study uses an ensemble of 10 Coupled Model Intercomparison Project(CMIP) models to investigate the projected change in agricultural flash drought during the 21st century. Comparison across geographical regions and climatic zones indicates that individual events are preceded by anomalously low relative humidity and precipitation, with long-term trends governed by changes in temperature, relative humidity, and soil moisture. As a result of these processes, the frequency of both upperlevel and root-zone flash drought is projected to more than double in the mid-and high latitudes over the 21st century, with hot spots developing in the temperate regions of Europe, and humid regions of South America, Europe, and southern Africa. 展开更多
关键词 flash drought climate change soil moisture agricultural drought CMIP
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Association of preschool children behavior and emotional problems with the parenting behavior of both parents 被引量:1
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作者 Su-Mei Wang Shuang-Qin Yan +4 位作者 Fang-Fang Xie Zhi-Ling Cai Guo-Peng Gao Ting-Ting Weng Fang-Biao Tao 《World Journal of Clinical Cases》 SCIE 2024年第6期1084-1093,共10页
BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.... BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.AIM To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children.METHODS From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool Children.Children’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional performance.Parenting behavior was evaluated using the Parental Behavior Inventory.Binomial logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting behaviors.RESULTS High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior problems.High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children.High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P<0.05).Moreover,paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors(all P>0.05),after calculating ratio of odds ratio values.CONCLUSION Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children.Overall,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or controlling the parents are,the more behavioral and emotional problems the children face.Moreover,the impact of fathers’parenting behaviors on preschool children’s behavior and emotions is no less significant than that of mothers’parenting behaviors. 展开更多
关键词 CHILDREN Preschool age PARENTING BEHAVIORAL Parenting problems
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Present Situation, Problems and Strategies of Agricultural Credit Policy in Dingxi City
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作者 Xiaoli ZHU Wenjie FAN Zongli ZHANG 《Asian Agricultural Research》 2023年第9期11-12,15,共3页
This paper analyzes the current situation of agricultural credit policy in Dingxi City,and further studies the problems in the implementation of credit policy in Dingxi City,and puts forward strategies and suggestions... This paper analyzes the current situation of agricultural credit policy in Dingxi City,and further studies the problems in the implementation of credit policy in Dingxi City,and puts forward strategies and suggestions according to these problems. 展开更多
关键词 agricultural credit policy agricultural development Dingxi City
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Analysis on the Problems and Strategies of Marketing Channels of Agricultural Products : Taking Liujun Lotus Root as an Example
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作者 Yue WANG 《Asian Agricultural Research》 2023年第9期19-21,24,共4页
Marketing channels are an important part of the circulation of agricultural products.With the development of China s agricultural industry,the marketing channels of agricultural products are continuously innovated and... Marketing channels are an important part of the circulation of agricultural products.With the development of China s agricultural industry,the marketing channels of agricultural products are continuously innovated and optimized.Taking Liujun Lotus Root as an example,on the basis of studying the existing model of marketing channels of agricultural products,this paper analyzes the problems in the existing marketing channels of Liujun Lotus Root,and puts forward relevant strategies. 展开更多
关键词 agricultural products Marketing channel Liujun Lotus Root
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Problems and Countermeasures for the Protection of Agricultural Heritage in China
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作者 YANG Yonggan 《Journal of Landscape Research》 2023年第4期65-68,共4页
With the rapid development of modern agriculture,China has increasingly attached importance to the protection and development of agricultural cultural heritage,but it has encountered severe challenges in reality.By an... With the rapid development of modern agriculture,China has increasingly attached importance to the protection and development of agricultural cultural heritage,but it has encountered severe challenges in reality.By analyzing the connotation and current situation of agricultural cultural heritage,to address the issues faced by China,such as imbalanced theoretical and practical development,difficulty in grasping the boundaries of protection and development,inadequate research and management mechanisms,large funding gaps,lack of talent,and insufficient international influence,targeted solutions are proposed based on relevant information and literature.This aims to strengthen the protection,activation,and inheritance of agricultural cultural heritage. 展开更多
关键词 agricultural cultural heritage Ecological protection Sustainable development Rural revitalization
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Spatio-Temporal Agricultural Drought Quantification in a Rainfed Agriculture, Athi-Galana-Sabaki River Basin
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作者 Joe Ndundi Tete Godfrey Ouma Makokha +2 位作者 Oscar Owino Ngesa John Ngugi Muthami Bonface Wabwire Odhiambo 《Journal of Geographic Information System》 2024年第4期201-226,共26页
This study employs a quantitative approach to comprehensively investigate the full propagation process of agricultural drought, focusing on pigeon peas (the most grown crop in the AGS Basin) planting seasonal variatio... This study employs a quantitative approach to comprehensively investigate the full propagation process of agricultural drought, focusing on pigeon peas (the most grown crop in the AGS Basin) planting seasonal variations. The study modelled seasonal variabilities in the seasonal Standardized Precipitation Index (SPI) and Standardized Agricultural Drought Index (SADI). To necessitate comparison, SADI and SPI were Normalized (from −1 to 1) as they had different ranges and hence could not be compared. From the seasonal indices, the pigeon peas planting season (July to September) was singled out as the most important season to study agricultural droughts. The planting season analysis selected all years with severe conditions (2008, 2009, 2010, 2011, 2017 and 2022) for spatial analysis. Spatial analysis revealed that most areas in the upstream part of the Basin and Coastal region in the lowlands experienced severe to extreme agricultural droughts in highlighted drought years. The modelled agricultural drought results were validated using yield data from two stations in the Basin. The results show that the model performed well with a Pearson Coefficient of 0.87 and a Root Mean Square Error of 0.29. This proactive approach aims to ensure food security, especially in scenarios where the Basin anticipates significantly reduced precipitation affecting water available for agriculture, enabling policymakers, water resource managers and agricultural sector stakeholders to equitably allocate resources and mitigate the effects of droughts in the most affected areas to significantly reduce the socioeconomic drought that is amplified by agricultural drought in rainfed agriculture river basins. 展开更多
关键词 agricultural Drought Food Security Standardized Precipitation Index Standardized agricultural
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Evolving patterns of agricultural production space in China:A network-based approach
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作者 Shuhui Yang Zhongkai Li +2 位作者 Jianlin Zhou Yancheng Gao Xuefeng Cui 《Geography and Sustainability》 CSCD 2024年第1期121-134,共14页
The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have p... The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological analysis.In this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in China.The results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past decades.The little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively stable.Additionally,identified provincial communities closely resemble China's agricultural natural zones.Furthermore,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural production.Despite the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special attentions.The findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development. 展开更多
关键词 agricultural system Complex network agricultural production space Proximity matrix Production capability
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A Comparative Study of Metaheuristic Optimization Algorithms for Solving Real-World Engineering Design Problems
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作者 Elif Varol Altay Osman Altay Yusuf Ovik 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期1039-1094,共56页
Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to solve.Such design problems are widely experienced in many engineering fields,such as ... Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to solve.Such design problems are widely experienced in many engineering fields,such as industry,automotive,construction,machinery,and interdisciplinary research.However,there are established optimization techniques that have shown effectiveness in addressing these types of issues.This research paper gives a comparative study of the implementation of seventeen new metaheuristic methods in order to optimize twelve distinct engineering design issues.The algorithms used in the study are listed as:transient search optimization(TSO),equilibrium optimizer(EO),grey wolf optimizer(GWO),moth-flame optimization(MFO),whale optimization algorithm(WOA),slimemould algorithm(SMA),harris hawks optimization(HHO),chimp optimization algorithm(COA),coot optimization algorithm(COOT),multi-verse optimization(MVO),arithmetic optimization algorithm(AOA),aquila optimizer(AO),sine cosine algorithm(SCA),smell agent optimization(SAO),and seagull optimization algorithm(SOA),pelican optimization algorithm(POA),and coati optimization algorithm(CA).As far as we know,there is no comparative analysis of recent and popular methods against the concrete conditions of real-world engineering problems.Hence,a remarkable research guideline is presented in the study for researchersworking in the fields of engineering and artificial intelligence,especiallywhen applying the optimization methods that have emerged recently.Future research can rely on this work for a literature search on comparisons of metaheuristic optimization methods in real-world problems under similar conditions. 展开更多
关键词 Metaheuristic optimization algorithms real-world engineering design problems multidisciplinary design optimization problems
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An Effective Meshless Approach for Inverse Cauchy Problems in 2D and 3D Electroelastic Piezoelectric Structures
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作者 Ziqiang Bai Wenzhen Qu Guanghua Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2955-2972,共18页
In the past decade,notable progress has been achieved in the development of the generalized finite difference method(GFDM).The underlying principle of GFDM involves dividing the domain into multiple sub-domains.Within... In the past decade,notable progress has been achieved in the development of the generalized finite difference method(GFDM).The underlying principle of GFDM involves dividing the domain into multiple sub-domains.Within each sub-domain,explicit formulas for the necessary partial derivatives of the partial differential equations(PDEs)can be obtained through the application of Taylor series expansion and moving-least square approximation methods.Consequently,the method generates a sparse coefficient matrix,exhibiting a banded structure,making it highly advantageous for large-scale engineering computations.In this study,we present the application of the GFDM to numerically solve inverse Cauchy problems in two-and three-dimensional piezoelectric structures.Through our preliminary numerical experiments,we demonstrate that the proposed GFDMapproach shows great promise for accurately simulating coupled electroelastic equations in inverse problems,even with 3%errors added to the input data. 展开更多
关键词 Generalized finite difference method meshless method inverse Cauchy problems piezoelectric problems electroelastic analysis
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Agricultural intensity for sustainable regional development:A case study in peri-urban areas of Karawang Regency,Indonesia
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作者 Setyardi Pratika MULYA Delik HUDALAH 《Regional Sustainability》 2024年第1期119-136,共18页
Peri-urban areas are playing an increasingly crucial role in the agricultural development and intensification in Indonesia.Peri-urban agriculture is highly vulnerable to change compared with urban and rural agricultur... Peri-urban areas are playing an increasingly crucial role in the agricultural development and intensification in Indonesia.Peri-urban agriculture is highly vulnerable to change compared with urban and rural agriculture,due to its location in transitional areas.Indicators of peri-urban agricultural intensity can help guide regional development.In this study,we assessed the sustainability of peri-urban areas based on agricultural intensity in Karawang Regency,Indonesia.We developed a village-based index to assess the region’s agricultural intensity by rescaling the village agriculture index(VAI)and combining the local sustainability index(LSI)with factor analysis.Since the unit of analysis is the village,we modified the LSI to the village sustainability index(VSI).In addition,we also developed a logical matrix analysis to determine the level of agricultural sustainability(LoAS)of each village.The combined results of the three indices(VAI,VSI,and LoAS)generated information about agricultural sustainability.The results indicated that peri-urban villages with high agricultural intensity tended to exhibit low levels of social welfare,economic development,and disaster risk.Moreover,high agricultural intensity did not necessarily ensure the prosperity of the people.Instead,there was the economic disparity among the villages in the study area.Encouraging diversity of agricultural intensity seems to be more critical than promoting agricultural intensity itself.Overall,this study highlights the distinctive characteristics and dynamic of peri-urban areas.New approaches,variables,and information regarding the combination of agricultural intensity and sustainability need to be developed as valuable tools for regional planning. 展开更多
关键词 agricultural intensity Village agriculture index(VAI) Village sustainability index(VSI) Level of agricultural sustainability(LoAS) Peri-urban areas Indonesia
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Unveiling the impact and mechanism of digital technology on agricultural economic resilience
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作者 Tianshu Quan Hui Zhang +1 位作者 Tianli Quan Yi Yu 《Chinese Journal of Population,Resources and Environment》 2024年第2期136-145,共10页
Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However... Enhancing the economic resilience of agriculture is essential for promoting sustainable and high-quality agricultural development.The emergence of digital technology has created new opportunities in this field.However,existing research predominantly focuses on traditional agricultural factors and technologies.Therefore,the impact of digital technology on agricultural economic resilience within the broader context of the“production-operation-industry”system in agriculture has not been comprehensively explored.To bridge this gap,this study analyzes panel data from 30 Chinese provinces from 2011 to 2020.It employs the static Van Dorn’s law and a dynamic spatial panel model to examine how digital technology empowers agricultural resilience.The findings indicate a continuous strengthening of digital technology development in China,albeit with significant polarization and spatial imbalances.Moreover,the resilience of the agricultural economy undergoes notable fluctuations,initially narrowing and subsequently displaying an upward trend.Digital technology clearly plays a pivotal role in empowering resilience through agricultural scale operation,industrial transformation,and technological progress.Its impact,particularly on the promotion of resilience in the eastern region and non-grain-producing areas and on high-level agricultural economies,also shows regional and technological variations. 展开更多
关键词 Digital technology agricultural economic resilience Counterfactual method Dynamic spatial panel model agricultural scale
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Professional Cognitive Education Model for Agricultural Water Conservancy Engineering under the Background of New Agricultural Science
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作者 Chong DU Da KONG Tangzhe NIE 《Asian Agricultural Research》 2024年第9期38-40,共3页
The construction of new agricultural science requires the use of modern scientific and technological means to transform and enhance current agricultural related majors.The agricultural water conservancy engineering ma... The construction of new agricultural science requires the use of modern scientific and technological means to transform and enhance current agricultural related majors.The agricultural water conservancy engineering major,with its inherent disciplinary advantages,plays an indispensable and important role in the construction of new agricultural science.In recent years,the lack of professional cognitive education has gradually become a significant problem in the training of talents in agricultural water conservancy engineering.Therefore,this paper deeply analyzes the problems and reasons faced by professional cognitive education,and proposes specific educational strategies for several key aspects such as enrollment promotion,freshman enrollment education,construction of teacher team,combination of scientific research and teaching,and strengthening professional cognition through competition activities.It aims to provide reference for improving the quality of professional cognitive education and exploring effective ways. 展开更多
关键词 NEW agricultural science construction PROFESSIONAL COGNITIVE education agricultural water conservancy engineering
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Highly Accurate Golden Section Search Algorithms and Fictitious Time Integration Method for Solving Nonlinear Eigenvalue Problems
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作者 Chein-Shan Liu Jian-Hung Shen +1 位作者 Chung-Lun Kuo Yung-Wei Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1317-1335,共19页
This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solve... This study sets up two new merit functions,which are minimized for the detection of real eigenvalue and complex eigenvalue to address nonlinear eigenvalue problems.For each eigen-parameter the vector variable is solved from a nonhomogeneous linear system obtained by reducing the number of eigen-equation one less,where one of the nonzero components of the eigenvector is normalized to the unit and moves the column containing that component to the right-hand side as a nonzero input vector.1D and 2D golden section search algorithms are employed to minimize the merit functions to locate real and complex eigenvalues.Simultaneously,the real and complex eigenvectors can be computed very accurately.A simpler approach to the nonlinear eigenvalue problems is proposed,which implements a normalization condition for the uniqueness of the eigenvector into the eigenequation directly.The real eigenvalues can be computed by the fictitious time integration method(FTIM),which saves computational costs compared to the one-dimensional golden section search algorithm(1D GSSA).The simpler method is also combined with the Newton iterationmethod,which is convergent very fast.All the proposed methods are easily programmed to compute the eigenvalue and eigenvector with high accuracy and efficiency. 展开更多
关键词 Nonlinear eigenvalue problem quadratic eigenvalue problem two new merit functions golden section search algorithm fictitious time integration method
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Linking 24-h Movement Behavior Guidelines to Cognitive Difficulties,Internalizing and Externalizing Problems in Preterm Youth
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作者 Zhihui Cheng Ailikute Aikeremu +6 位作者 Yanping Gao Zhihao Zhang Anthony G.Delli Paoli Paolo Marcello Cunha Alyx Taylor Fabian Herold Liye Zou 《International Journal of Mental Health Promotion》 2024年第8期651-662,共12页
Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether ... Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether meeting the 24-h movement behavior(24-HMB)guidelines,which include recommendations on physical activity(PA),screen time(ST),and sleep(SL),is related to indicators of cognitive difficulties,internalizing problems(e.g.,depression and anxiety),and externalizing problems(e.g.,difficulties in making friends and arguing)in a sample of preterm youth(children and adolescents born preterm).Methods:In this cross-sectional study,data from 3410 preterm youth(aged 6 to 17 years)were included for data analyses.Multivariable logistic regression was used to investigate associations between meeting the 24-HMB guidelines and the above-mentioned health outcomes,while controlling for sociodemographic and health-related factors.Results:The prevalence of meeting 24-HMB guidelines varied across independent and integrated components of the 24-HMB guidelines.Meeting the ST guideline alone(p<0.05)and integrated guidelines(i.e.,ST+SL and ST+SL+PA)were associated with fewer cognitive difficulties and reduced internalizing and externalizing problems(p<0.05).Specifically,meeting the SL guideline alone and integrated guidelines(i.e.,SL+ST)were associated with lower odds of depression and anxiety(p<0.01).Additionally,meeting independent,and integrated(PA and/or ST)guidelines were associated with less pronounced difficulties in making friends and arguing(p<0.05).Meeting 24-HMB guidelines in an isolated and integrated manner are linked to better cognitive performance and fewer internalizing and externalizing problems in preterm youth.Conclusion:Results suggest that advocating for the implementation of the 24-HMB guidelines may reduce cognitive challenges and behavioral issues,which is of high relevance for improving public health.Future longitudinal studies in preterm youth should investigate how modifying specific 24-HMB behaviors,especially ST,influence cognitive difficulties,internalizing and externalizing problems in this vulnerable population. 展开更多
关键词 Cognitive difficulties externalizing problems internalizing problems physical activity preterm youth
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Thoughts on Pairing Assistance to Tibet for Promoting Agricultural High-quality Development in Southern Tibet from the Perspective of Agricultural Power
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作者 Zhiguo SUN Li GAO +3 位作者 Yuanpeng SUN Guangchao CAO Xinying ZHOU Xiaoqiang LI 《Asian Agricultural Research》 2024年第3期18-24,共7页
In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style mod... In the new era,there is an urgent need to further promote pairing assistance to Tibet,promote the simultaneous construction of a strong agriculture in Tibet and the China's Mainland,and compose a Chinese-style modernization.Southern Tibet,located in the southeastern part of the Tibet Autonomous Region,includes Shannan City and Nyingchi City,is a region assisted by four provincial partners including Hubei Province.This paper introduces the agricultural environment in southern Tibet,studies its agricultural characteristics,and analyzes the main issues of its pairing assistance.Taking forging the strong consciousness of the Chinese national community as the main line,the paper explores strategies for promoting agricultural high-quality development in southern Tibet through pairing assistance to Tibet from the perspective of agricultural power,and proposes some strategies,such as inheriting agricultural cultural heritage,promoting the upgrading of modern seed industry,enhancing the characteristic advantages of highland barley(naked barley)and animal husbandry industries,and developing edible fungi and cold water fish industries. 展开更多
关键词 PAIRING ASSISTANCE to TIBET Southern TIBET Shannan CITY Nyingchi CITY agricultural high-quality development agricultural power
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Optimal Shape Factor and Fictitious Radius in the MQ-RBF:Solving Ill-Posed Laplacian Problems
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作者 Chein-Shan Liu Chung-Lun Kuo Chih-Wen Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3189-3208,共20页
To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection techniq... To solve the Laplacian problems,we adopt a meshless method with the multiquadric radial basis function(MQRBF)as a basis whose center is distributed inside a circle with a fictitious radius.A maximal projection technique is developed to identify the optimal shape factor and fictitious radius by minimizing a merit function.A sample function is interpolated by theMQ-RBF to provide a trial coefficient vector to compute the merit function.We can quickly determine the optimal values of the parameters within a preferred rage using the golden section search algorithm.The novel method provides the optimal values of parameters and,hence,an optimal MQ-RBF;the performance of the method is validated in numerical examples.Moreover,nonharmonic problems are transformed to the Poisson equation endowed with a homogeneous boundary condition;this can overcome the problem of these problems being ill-posed.The optimal MQ-RBF is extremely accurate.We further propose a novel optimal polynomial method to solve the nonharmonic problems,which achieves high precision up to an order of 10^(−11). 展开更多
关键词 Laplace equation nonharmonic boundary value problem Ill-posed problem maximal projection optimal shape factor and fictitious radius optimal MQ-RBF optimal polynomial method
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Identifying multidisciplinary problems from scientific publications based on a text generation method
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作者 Ziyan Xu Hongqi Han +2 位作者 Linna Li Junsheng Zhang Zexu Zhou 《Journal of Data and Information Science》 CSCD 2024年第3期213-237,共25页
Purpose:A text generation based multidisciplinary problem identification method is proposed,which does not rely on a large amount of data annotation.Design/methodology/approach:The proposed method first identifies the... Purpose:A text generation based multidisciplinary problem identification method is proposed,which does not rely on a large amount of data annotation.Design/methodology/approach:The proposed method first identifies the research objective types and disciplinary labels of papers using a text classification technique;second,it generates abstractive titles for each paper based on abstract and research objective types using a generative pre-trained language model;third,it extracts problem phrases from generated titles according to regular expression rules;fourth,it creates problem relation networks and identifies the same problems by exploiting a weighted community detection algorithm;finally,it identifies multidisciplinary problems based on the disciplinary labels of papers.Findings:Experiments in the“Carbon Peaking and Carbon Neutrality”field show that the proposed method can effectively identify multidisciplinary research problems.The disciplinary distribution of the identified problems is consistent with our understanding of multidisciplinary collaboration in the field.Research limitations:It is necessary to use the proposed method in other multidisciplinary fields to validate its effectiveness.Practical implications:Multidisciplinary problem identification helps to gather multidisciplinary forces to solve complex real-world problems for the governments,fund valuable multidisciplinary problems for research management authorities,and borrow ideas from other disciplines for researchers.Originality/value:This approach proposes a novel multidisciplinary problem identification method based on text generation,which identifies multidisciplinary problems based on generative abstractive titles of papers without data annotation required by standard sequence labeling techniques. 展开更多
关键词 Problem identification MULTIDISCIPLINARY Text generation Text classification
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Oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions via Prufer transformation
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作者 LI Zhi-yu LI Kun +2 位作者 CAI Jin-ming QIN Jian-fang ZHENG Zhao-wen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期191-200,共10页
A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in ... A class of Sturm-Liouville problems with discontinuity is studied in this paper.The oscillation properties of eigenfunctions for Sturm-Liouville problems with interface conditions are obtained.The main method used in this paper is based on Prufer transformation,which is different from the classical ones.Moreover,we give two examples to verify our main results. 展开更多
关键词 Sturm-Liouville problem interface condition oscillatory solution
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Demography and Socio-Economic Aspects on Irrigated Smallholder Agricultural Enterprises and Their Association with the Cultivation of Maize (Zea mays L.) as a Selected Field Crop
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作者 Tsumbedzo Jutas Mavhungu Azwihangwisi Edward Nesamvuni +2 位作者 Khathutshelo Alfred Tshikolomo Ndivhudzannyi Sylvestor Mpandeli Johan Adriaan van Niekerk 《Agricultural Sciences》 2024年第7期729-741,共13页
The purpose of this study is to correlate demography and socio-economic aspects at Irrigated Smallholder Agricultural Enterprises and their association with the Cultivation of Maize in order to determine its positive ... The purpose of this study is to correlate demography and socio-economic aspects at Irrigated Smallholder Agricultural Enterprises and their association with the Cultivation of Maize in order to determine its positive impacts at irrigated smallholders’ agricultural entrepreneurs’ household. Chi-square test was used as descriptive analysis method. The Fischer Exact tests were employed to test demography (gender, age, education, and income) in winter and summer production season of irrigated smallholder agricultural enterprises and their association with the cultivation of selected field crop (i.e. maize). The results show that gender results were not being statistically significant, as measured by the Phi measure of effect size, φ = 0.149, p = 0.011, and φ = 0.05, p = 0.392 in summer. As far as age is concern, it appears to be a statistically significant association between cultivating maize and age in winter, φ = 0.046, p = 0.730 in winter and φ = 0.172, p = 0.013. Education winter result not being statistically significant, the effect size showed a weak association, as measured by the Phi measure of effect size, φ = 0.112, p = 0.305 and φ = 0.035, p = 0.948 in summer. Income result not being statistically significant, as measured by the Phi measure of effect size, φ = 0.049, p = 0.399 and φ = 0.081, p = 0.166 in summer. In conclusion, the study shows that the development of best management practices must be based on a comprehensive analysis of the livelihoods and irrigated smallholder agricultural enterprise farming styles of participating irrigated smallholder agricultural entrepreneurs. 展开更多
关键词 MAIZE ASSOCIATION Irrigated Smallholder agricultural Enterprises DEMOGRAPHY Livelihoods
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An agent-based model of agricultural land expansion in the mountain forest of Timor Island,Indonesia
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作者 PUJIONO Eko SADONO Ronggo +12 位作者 IMRON Muhammad Ali SUTOMO JANUAR Hedi Indra KUSWANDI Relawan KURNIAWAN Hery HADI Etik Erna Wati SAPUTRA Muhammad Hadi HIDAYAH Izhamil HUMAIDA Nida SUKMAWATI Jalma Giring HADIYAN Yayan NUGROHO Agung Wahyu HANI Aditya 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2263-2282,共20页
The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns ... The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns indicate that deforestation primarily occurs at lower elevations and near the boundaries of forests and settlements,often associated with shifting cultivation by local farmers.This study adopts a process-based modelling approach,specifically the agent-based model,to simulate land changes,particularly farmers'expansion of agricultural land around the Mutis mountain forest.The underlying concept of this agent-based approach is the interaction between the human and environmental systems.Farmers,representing the human system,interact with the land,which represents the environmental system,through land use decision-making mechanisms.The research was conducted in the Community Forest of the Timor Tengah Utara District,one of the sites within the Mutis-Timau Forest Complex with the highest deforestation rate.Land use change simulations were performed using agent-based modelling from 1999 to 2030,considering the socio-economic conditions of farmers,spatial preferences,land use decisions,and natural transitions.The results revealed that the agricultural area increased by 14%under the Business as Usual scenario and 5%under the Reducing Emission from Deforestation and Forest Degradation scenario,compared to the initial agricultural area of 245 hectares.The probability of farmers deciding to extend agricultural activities was positively associated with the number of livestock maintained by farmers and the size of the village area.Conversely,the likelihood of farmers opting for agricultural extensification decreased with an increase in the area of private land and the farmer's age.These findings are crucial for the managers of the Mutis-Timau Forest Complex and other relevant stakeholders,as they aid in arranging actions to combat deforestation,designing proper forest-related policies,and providing support for initiatives such as reducing emissions from deforestation and forest degradation programs or further incentive schemes. 展开更多
关键词 agricultural land expansion Simulation Agent-based model FARMER DEFORESTATION Mountainous tropical forest
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