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Study on Technologies for Information Monitoring and Quick Response of Agricultural Focuses and Significant Events 被引量:2
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作者 ZHAO Rui-xue KOU Yuan-tao XIAN Guo-jian MAO Guang-wei 《Agricultural Sciences in China》 CAS CSCD 2010年第5期764-770,共7页
This article analyzed the importance of information monitoring and quick response on agricultural focuses and significant events, proposed the workflow and technical framework for information monitoring and quick resp... This article analyzed the importance of information monitoring and quick response on agricultural focuses and significant events, proposed the workflow and technical framework for information monitoring and quick response based on modern information technologies, and explained key technologies during implementation and the functional structure for prototype system of the technical support platform. 展开更多
关键词 agricultural focus significant event information monitoring quick response technical platform
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Research and application of real-time monitoring and early warning thresholds for multi-temporal agricultural products information 被引量:2
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作者 XU Shi-wei WANG Yu +1 位作者 WANG Sheng-wei LI Jian-zheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第10期2582-2596,共15页
Monitoring and early warning is an important means to effectively prevent risks in agricultural production,consumption and price.In particular,with the change of modes of national administration against the background... Monitoring and early warning is an important means to effectively prevent risks in agricultural production,consumption and price.In particular,with the change of modes of national administration against the background of big data,improving the capacity to monitor agricultural products is of great significance for macroeconomic decision-making.Agricultural product information early warning thresholds are the core of agricultural product monitoring and early warning.How to appropriately determine the early warning thresholds of multi-temporal agricultural product information is a key question to realize real-time and dynamic monitoring and early warning.Based on the theory of abnormal fluctuation of agricultural product information and the research of substantive impact on the society,this paper comprehensively discussed the methods to determine the thresholds of agricultural product information fluctuation in different time dimensions.Based on the data of the National Bureau of Statistics of China(NBSC)and survey data,this paper used a variety of statistical methods to determine the early warning thresholds of the production,consumption and prices of agricultural products.Combined with Delphi expert judgment correction method,it finally determined the early warning thresholds of agricultural product information in multiple time,and carried out early warning analysis on the fluctuation of agricultural product monitoring information in 2018.The results show that:(1)the daily,weekly and monthly monitoring and early warning thresholds of agricultural products play an important early warning role in monitoring abnormal fluctuations with agricultural products;(2)the multitemporal monitoring and early warning thresholds of agricultural product information identified by the research institute can provide effective early warning on current abnormal fluctuation of agricultural product information,provide a benchmarking standard for China's agricultural production,consumption and price monitoring and early warning at the national macro level,and further improve the application of China's agricultural product monitoring and early warning. 展开更多
关键词 agricultural product information monitoring and early warning THRESHOLD MULTI-TEMPORAL real-time dynamics
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Farmers’ Access to Agricultural Information Sources: Evidences from Rural Pakistan
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作者 Muhammad Yaseen Shiwei Xu +1 位作者 Wen Yu Sadia Hassan 《Journal of Agricultural Chemistry and Environment》 2016年第1期12-19,共8页
The current study was conducted to probe farmers’ accessible agricultural information sources in rural areas of Pakistan. For this purpose a random sample of 160 households from four districts of the Punjab province ... The current study was conducted to probe farmers’ accessible agricultural information sources in rural areas of Pakistan. For this purpose a random sample of 160 households from four districts of the Punjab province of Pakistan was selected. Data were collected using validated and expert reviewed questionnaire with the help of interview method. The results revealed that majority of farmers (47.5%) ranked neighbor-friends-relatives as first source of information while 31.9% of farmers ranked this source as second and 33.7% farmers’ ranked it as third major source. With contrast to this very less farmers (10%) ranked agricultural extension staff as first information source. Keeping in view the study results, the performance of extension staff is not encouraging;therefore government should plan and launch a policy to foster performance of public agricultural extension system to fulfill the advanced technological needs of farmers to flourish sustainable agriculture and rural development. 展开更多
关键词 EXTENSION FARMER Information Source Pakistan
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Nutrition impacts of non-solid cooking fuel adoption on under-five children in developing countries 被引量:1
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作者 Yalin Tang Yuhe Guo +1 位作者 Gang Xie Chengfang Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期397-413,共17页
This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demogra... This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia. 展开更多
关键词 non-solid cooking fuel nutrition benefits under-five children developing countries
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Resilience effects for household food expenditure and dietary diversity in rural western China 被引量:1
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作者 Xiao Han Kaiyu Lyu +1 位作者 Fengying Nie Yuquan Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期384-396,共13页
A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in weste... A more resilient livelihood is increasingly recognized as an efficient way to improve vulnerable households’food security and optimize their dietary decisions.This study quantifies rural household resilience in western China,identifies the three pillars(absorptive capacity,adaptive capacity,and transformative capacity)contribution to resilience,and then establishes the estimated Resilience Capacity Index(RCI)linked with food security and dietary diversity supported by the multiple indicator multiple cause(MIMIC)model.Results show that,despite geographical heterogeneity,the RCI consistently increased from 2015 to 2021.Households with a higher RCI inheriting better capacity to deal with risk and shocks are significantly and positively correlated with increasing food expenditure and diversifying food choices.It can be because resilient households will allocate more money to food expenditure instead of saving for livelihood uncertainty.Thus,policymakers can provide more incentives for rural households to adopt more dynamic and effective risk management strategies.This,in turn,could yield positive spillover effects by preventing human capital loss associated with dietary-related chronic diseases and mortality. 展开更多
关键词 RESILIENCE food expenditure dietary diversity China risk management
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Invasion of fall armyworm led to the succession of maize pests in Southwest China
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作者 Zezheng Fan Yifei Song +1 位作者 Shengyuan Zhao Kongming Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1300-1314,共15页
The invasive fall armyworm Spodoptera frugiperda(J.E.Smith)invaded Asia in 2018,colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and sum... The invasive fall armyworm Spodoptera frugiperda(J.E.Smith)invaded Asia in 2018,colonizing the tropical and southern subtropical regions as well as migrating with the monsoons into Northeast Asia during spring and summer.This has resulted in widespread infestations,with significant impacts on maize production in various Asian countries.Previous studies have shown that the invasion of this pest can alter the species relationships of maize pests,but the actual impact on maize pest management is still unclear.This study investigated the changes in maize pest occurrence and pesticide use in the annual breeding areas of S.frugiperda in Yunnan Province and the Guangxi Zhuang Autonomous Region of China during 2017-2021,based on surveys and interviews with small farmers in maize production.The results showed that S.frugiperda has emerged as the dominant species among maize pests after invasion and colonization,replacing traditional pests such as Ostrinia furnacalis,Spodoptera litura,Agrotis ypsilon,and Rhopalosiphum maidis.The variety of pesticides used for maize pest control has changed from chlorpyrifos,lambda-cyhalothrin,and acetamiprid to emamectin benzoate-based pesticides with high effectiveness against S.frugiperda.Furthermore,the frequency of maize pest chemical applications has increased from an average of 5.88 to 7.21 times per season,with the amounts of pesticides used in summer and autumn maize being significantly higher than in winter and spring maize,thereby increasing application costs by more than 35%.The results of this study clarified the impact of S.frugiperda invasion on maize pest community succession and chemical pesticide use in tropical and south subtropical China,thereby providing a baseline for modifying the regional control strategies for maize pests after the invasion of this relatively new pest. 展开更多
关键词 Spodoptera frugiperda annual breeding region sweet waxy corn economic evaluation
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Temporal and spatial evolution of global major grain trade patterns
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作者 Ziqi Yin Jiaxuan Hu +3 位作者 Jing Zhang Xiangyang Zhou Lingling Li Jianzhai Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1075-1086,共12页
The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain ... The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks. 展开更多
关键词 grain trade pattern evolution complex network
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China agricultural outlook for 2015–2024 based on China Agricultural Monitoring and Early-warning System(CAMES) 被引量:12
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作者 XU Shi-wei LI Gan-qiong LI Zhe-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1889-1902,共14页
The primary goal of Chinese agricultural development is to guarantee national food security and supply of major agricultural products. Hence, the scientiifc work on agricultural monitoring and early warning as wel as ... The primary goal of Chinese agricultural development is to guarantee national food security and supply of major agricultural products. Hence, the scientiifc work on agricultural monitoring and early warning as wel as agricultural outlook must be strengthened. In this study, we develop the China Agricultural Monitoring and Early-warning System (CAMES) on the basis of a comparative study of domestic and international agricultural outlook models. The system is a dynamic and multi-market partial equilibrium model that integrates biological mechanisms with economic mechanisms. This system, which includes 11 categories of 953 kinds of agricultural products, could dynamical y project agricultural market supply and demand, assess food security, and conduct scenario analysis at different spatial levels, time scale levels, and macro-micro levels. Based on the CAMES, the production, consumption, and trade of the major agricultural products in China over the next decade are projected. The fol owing conclusions are drawn:i) The production of major agricultural products wil continue to grow steadily, mainly because of the increase in yield. i ) The growth of agricultural consumption wil be slightly higher than that of agricultural production. Meanwhile, a high self-sufifciency rate is expected for cereals such as rice, wheat, and maize, with the rate being stable at around 97%. i i) Agricultural trade wil continue to thrive. The growth of soybean and milk im-ports wil slow down, but the growth of traditional agricultural exports such as vegetables and fruits is expected to continue. 展开更多
关键词 agricultural outlook PROJECTION China Agricultural Monitoring and Early-warning System(CAMES) agriculture of China
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Using Quantile Regression Approach to Analyze Price Movements of Agricultural Products in China 被引量:7
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作者 LI Gan-qiong XU Shi-wei +2 位作者 LI Zhe-min SUN Yi-guo DONG Xiao-xia 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第4期674-683,共10页
This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data hete... This paper studies how the price movements of pork,chicken and egg respond to those of related cost factors in short terms in Chinese market.We employ a linear quantile approach not only to explore potential data heteroscedasticity but also to generate confidence bands for the purpose of price stability study.We then evaluate our models by comparing the prediction intervals generated from the quantile regression models with in-sample and out-of-sample forecasts.Using monthly data from January 2000 to October 2010,we observed these findings:(i) the price changes of cost factors asymmetrically and unequally influence those of the livestock across different quantiles;(ii) the performance of our models is robust and consistent for both in-sample and out-of-sample forecasts;(iii) the confidence intervals generated from 0.05th and 0.95th quantile regression models are good methods to forecast livestock price fluctuation. 展开更多
关键词 cost factors agricultural products forecasting price movements quantile regression model
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ICT-based agricultural advisory services and nitrogen management practices:A case study of wheat production in China 被引量:1
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作者 DING Ji-ping LI Jing-han +2 位作者 LIU Jia-huan ZHANG Wei-feng JIA Xiang-ping 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第6期1799-1811,共13页
Excessive use of nitrogen fertilizer in China and its adverse effects on agricultural production have been a national and global concern.In addition to massive public initiatives to promote sustainable farm practices,... Excessive use of nitrogen fertilizer in China and its adverse effects on agricultural production have been a national and global concern.In addition to massive public initiatives to promote sustainable farm practices,grass-rooted innovations are emerging in the niche,many of which take the forms of information and communication technologies(ICT)and digital services.This study examines the effects of ICT-based extension services provided by an entrepreneurial startup on adopting sustainable farming practices.We found no significant reduction in N-fertilizer use for wheat production.But the ICT-based services promoted farmers to adapt N-fertilizer use towards site-specific management.The business model of the entrepreneurial venture faces great challenges in becoming participatory and financially sustainable. 展开更多
关键词 venture capital innovations precision farming private-public partnerships nitrogen management
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Thoughts on Participation of Supply and Marketing Cooperative System in Agricultural Social Service 被引量:1
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作者 Yong YANG Wensheng WANG Min LI 《Asian Agricultural Research》 2018年第8期1-4,8,共5页
Agricultural social service is an important field in the development of modern agriculture. At present,agricultural social service should be based on the extension of the agricultural industrial chain and value chain.... Agricultural social service is an important field in the development of modern agriculture. At present,agricultural social service should be based on the extension of the agricultural industrial chain and value chain. The supply and marketing system has important opportunity to participate in social services. It should be based on deep reform of supply and marketing system,rural industrial poverty alleviation,sustainable agricultural ecological development,development of farmers' cooperative organizations,and increase of organization efficiency. It is recommended to undertake works in construction of platform of supply of agricultural products,commercialization of agricultural technology services,scale development of community-supported agriculture,and market based agricultural social capital. Through improving the team system of supply and marketing system,it is recommended to create platform-based flattening environment and create cooperative ecology in PPP mode to guarantee. 展开更多
关键词 农业 社会化服务 发展现状 经济发展
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Construction and development of the Agricultural Science Data Center
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作者 MENG Xianxue 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第4期349-352,共4页
Science data are very important resources for innovative research in all scientific disciplines. The Ministry of Science and Technology (MOST) of China has launched a comprehensive platform program for supporting sc... Science data are very important resources for innovative research in all scientific disciplines. The Ministry of Science and Technology (MOST) of China has launched a comprehensive platform program for supporting scientific innovations and agricultural science database construction and sharing project is one of the activities under this program supported by MOST. This paper briefly described the achievements of the Agricultural Science Data Center Project. 展开更多
关键词 DATABASE science data data center information management
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Application of Security Index in Evaluation of Agricultural Insurance Security Level
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作者 Xuan ZUO Qiao ZHANG Ke WANG 《Asian Agricultural Research》 2018年第2期39-41,共3页
At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for ag... At present,there is still no unified standard for evaluation of agricultural insurance security level,especially in the quantitative evaluation. In order to explore a scientific and reasonable evaluation method for agricultural insurance security level,this paper analyzed the current situation of evaluation methods of social insurance,endowment insurance and medical insurance,as well as the application of security index. It is expected to provide a certain reference for evaluation of agricultural insurance security level by the agricultural insurance security index. 展开更多
关键词 Agricultural Insurance Security level EVALUATION Security index
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Construction of personalized knowledg environment for professional libraries:From the practice of Chinese National Agricultural Library
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作者 Ruixue ZHAO Xianxue MENG Yuantao KOU 《Chinese Journal of Library and Information Science》 2013年第4期1-15,共15页
Purpose:Centralized on the construction of a personalized knowledge environment that can better meet the need of Chinese agricultural researchers,this paper presents the practice conducted by the National Agricultural... Purpose:Centralized on the construction of a personalized knowledge environment that can better meet the need of Chinese agricultural researchers,this paper presents the practice conducted by the National Agricultural Library(NAL)of Chinese Academy of Agricultural Sciences(CAAS)in the digital research environment.Based on the analysis of information needs of Chinese agricultural researchers,CAAS constructed digital research environments for its researchers at different levels,by means of providing more professional knowledge services for targeted researcher users.Design/methodology/approach:On the basis of the construction of public service platform—National Agriculture Information System of the Library of CAAS(i.e.NAL),local resources were integrated with public open resources by using key technologies,such as Web 2.0,knowledge navigation,linked data and intelligent retrieval,to construct an institutional personalized digital repository for CAAS researchers.Findings:By using the construction tool CAASPKE,knowledge environment platforms have been constructed for 10 CAAS institutes,taking roughly 33%of CAAS institutes.In addition,16 discipline information environment platforms have been set up for CAAS research teams,and 5 professional digital libraries for provincial agricultural academies,which spread in Beijing,Shanxi,Sichuan,and the Xinjiang and Tibet Autonomous Regions.Research limitations:User’s local collections ought to be integrated with IR resources of the CAAS platform constantly.Due to the lack of overall knowledge resources,functions of the platform have not been fully explored,so the effect need be evaluated with the time being.Practical implications:The construction of research knowledge environment in CAAS has not only contributed to the development of its personalized knowledge service system,but also made the functions of libraries transformed into the information service system.In this case,CAAS libraries are now playing more and more important roles in the innovation process of Chinese agricultural researchers.Originality/value:The innovative practice is the first endeavor that ever implemented in the agricultural information service area across China’s mainland.The construction tool developed for the knowledge environment of personalization could customize resources flexibly according to the need of different CAAS users,and it can organize the knowledge resources of CAAS institutes effectively. 展开更多
关键词 Personalized service Knowledge service Research knowledge environment Digital library Institutional repository Personalized service tool
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Visual learning graph convolution for multi-grained orange quality grading 被引量:1
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作者 GUAN Zhi-bin ZHANG Yan-qi +4 位作者 CHAI Xiu-juan CHAI Xin ZHANG Ning ZHANG Jian-hua SUN Tan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第1期279-291,共13页
The quality of oranges is grounded on their appearance and diameter.Appearance refers to the skin’s smoothness and surface cleanliness;diameter refers to the transverse diameter size.They are visual attributes that v... The quality of oranges is grounded on their appearance and diameter.Appearance refers to the skin’s smoothness and surface cleanliness;diameter refers to the transverse diameter size.They are visual attributes that visual perception technologies can automatically identify.Nonetheless,the current orange quality assessment needs to address two issues:1)There are no image datasets for orange quality grading;2)It is challenging to effectively learn the fine-grained and distinct visual semantics of oranges from diverse angles.This study collected 12522 images from 2087 oranges for multi-grained grading tasks.In addition,it presented a visual learning graph convolution approach for multi-grained orange quality grading,including a backbone network and a graph convolutional network(GCN).The backbone network’s object detection,data augmentation,and feature extraction can remove extraneous visual information.GCN was utilized to learn the topological semantics of orange feature maps.Finally,evaluation results proved that the recognition accuracy of diameter size,appearance,and fine-grained orange quality were 99.50,97.27,and 97.99%,respectively,indicating that the proposed approach is superior to others. 展开更多
关键词 GCN MULTI-VIEW FINE-GRAINED visual feature APPEARANCE diameter size
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Ensemble learning prediction of soybean yields in China based on meteorological data 被引量:1
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作者 LI Qian-chuan XU Shi-wei +3 位作者 ZHUANG Jia-yu LIU Jia-jia ZHOU Yi ZHANG Ze-xi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1909-1927,共19页
The accurate prediction of soybean yield is of great significance for agricultural production, monitoring and early warning.Although previous studies have used machine learning algorithms to predict soybean yield base... The accurate prediction of soybean yield is of great significance for agricultural production, monitoring and early warning.Although previous studies have used machine learning algorithms to predict soybean yield based on meteorological data,it is not clear how different models can be used to effectively separate soybean meteorological yield from soybean yield in various regions. In addition, comprehensively integrating the advantages of various machine learning algorithms to improve the prediction accuracy through ensemble learning algorithms has not been studied in depth. This study used and analyzed various daily meteorological data and soybean yield data from 173 county-level administrative regions and meteorological stations in two principal soybean planting areas in China(Northeast China and the Huang–Huai region), covering 34 years.Three effective machine learning algorithms(K-nearest neighbor, random forest, and support vector regression) were adopted as the base-models to establish a high-precision and highly-reliable soybean meteorological yield prediction model based on the stacking ensemble learning framework. The model's generalizability was further improved through 5-fold crossvalidation, and the model was optimized by principal component analysis and hyperparametric optimization. The accuracy of the model was evaluated by using the five-year sliding prediction and four regression indicators of the 173 counties, which showed that the stacking model has higher accuracy and stronger robustness. The 5-year sliding estimations of soybean yield based on the stacking model in 173 counties showed that the prediction effect can reflect the spatiotemporal distribution of soybean yield in detail, and the mean absolute percentage error(MAPE) was less than 5%. The stacking prediction model of soybean meteorological yield provides a new approach for accurately predicting soybean yield. 展开更多
关键词 meteorological factors ensemble learning crop yield prediction machine learning county-level
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Nonreciprocity of energy transfer in a nonlinear asymmetric oscillator system with various vibration states 被引量:1
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作者 Jian’en CHEN Jianling LI +3 位作者 Minghui YAO Jun LIU Jianhua ZHANG Min SUN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第5期727-744,共18页
The nonreciprocity of energy transfer is constructed in a nonlinear asymmetric oscillator system that comprises two nonlinear oscillators with different parameters placed between two identical linear oscillators.The s... The nonreciprocity of energy transfer is constructed in a nonlinear asymmetric oscillator system that comprises two nonlinear oscillators with different parameters placed between two identical linear oscillators.The slow-flow equation of the system is derived by the complexification-averaging method.The semi-analytical solutions to this equation are obtained by the least squares method,which are compared with the numerical solutions obtained by the Runge-Kutta method.The distribution of the average energy in the system is studied under periodic and chaotic vibration states,and the energy transfer along two opposite directions is compared.The effect of the excitation amplitude on the nonreciprocity of the system producing the periodic responses is analyzed,where a three-stage energy transfer phenomenon is observed.In the first stage,the energy transfer along the two opposite directions is approximately equal,whereas in the second stage,the asymmetric energy transfer is observed.The energy transfer is also asymmetric in the third stage,but the direction is reversed compared with the second stage.Moreover,the excitation amplitude for exciting the bifurcation also shows an asymmetric characteristic.Chaotic vibrations are generated around the resonant frequency,irrespective of which linear oscillator is excited.The excitation threshold of these chaotic vibrations is dependent on the linear oscillator that is being excited.In addition,the difference between the energy transfer in the two opposite directions is used to further analyze the nonreciprocity in the system.The results show that the nonreciprocity significantly depends on the excitation frequency and the excitation amplitude. 展开更多
关键词 NONRECIPROCITY strong nonlinearity energy transfer chaotic vibration higher branch of response
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Accurate recognition of the reproductive development status and prediction of oviposition fecundity in Spodoptera frugiperda(Lepidoptera:Noctuidae)based on computer vision 被引量:1
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作者 LÜChun-yang GE Shi-shuai +4 位作者 HE Wei ZHANG Hao-wen YANG Xian-ming CHU Bo WU Kong-ming 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2173-2187,共15页
Spodoptera frugiperda(Lepidoptera:Noctuidae)is an important migratory agricultural pest worldwide,which has invaded many countries in the Old World since 2016 and now poses a serious threat to world food security.The ... Spodoptera frugiperda(Lepidoptera:Noctuidae)is an important migratory agricultural pest worldwide,which has invaded many countries in the Old World since 2016 and now poses a serious threat to world food security.The present monitoring and early warning strategies for the fall army worm(FAW)mainly focus on adult population density,but lack an information technology platform for precisely forecasting the reproductive dynamics of the adults.In this study,to identify the developmental status of the adults,we first utilized female ovarian images to extract and screen five features combined with the support vector machine(SVM)classifier and employed male testes images to obtain the testis circular features.Then,we established models for the relationship between oviposition dynamics and the developmental time of adult reproductive organs using laboratory tests.The results show that the accuracy of female ovary development stage determination reached 91%.The mean standard error(MSE)between the actual and predicted values of the ovarian developmental time was 0.2431,and the mean error rate between the actual and predicted values of the daily oviposition quantity was 12.38%.The error rate for the recognition of testis diameter was 3.25%,and the predicted and actual values of the testis developmental time in males had an MSE of 0.7734.A WeChat applet for identifying the reproductive developmental state and predicting reproduction of S.frugiperda was developed by integrating the above research results,and it is now available for use by anyone involved in plant protection.This study developed an automated method for accurately forecasting the reproductive dynamics of S.frugiperda populations,which can be helpful for the construction of a population monitoring and early warning system for use by both professional experts and local people at the county level. 展开更多
关键词 Spodoptera frugiperda computer vision OVARY TESTIS WeChat applet
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Evaluation of Holstein cows with different tongue‑rolling frequencies:stress immunity,rumen environment and general behavioural activity
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作者 Fuyu Sun Xiaoyang Chen +2 位作者 Yongfeng Li Guangyong Zhao Xianhong Gu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2686-2700,共15页
Background The tongue-rolling behaviour of cows is regarded as an outward sign of stressed animals in a low welfare status.The primary aim of this observational study was to evaluate the association between the freque... Background The tongue-rolling behaviour of cows is regarded as an outward sign of stressed animals in a low welfare status.The primary aim of this observational study was to evaluate the association between the frequency of tongue-rolling behaviour and its physiological function.The secondary aim was to explore the relationship between general activities and the frequency of tongue-rolling behaviour of cows.A total of 126 scan sampling behavioural observations were collected over 7 d on 348 Holstein cows with the same lactation stage in the same barn.The tongue-rolling frequency was defined as the number of tongue-rolling observations as a percentage to the total observations per individual cow.According to their tongue-rolling frequency,the cows were grouped into the CON(no tongue-rolling),LT(frequency 1%),MT(frequency 5%),and HT(frequency 10%)groups.Six cows from each group were randomly selected for sampling.Serum samples,rumen fluid,milk yield,and background infor-mation were collected.The general behaviour data during 72 continuous hours of dairy cows,including eating time,rumination time,food time(eating time+rumination time),and lying time,were recorded by the collar sensor.Results Cortisol(P=0.012),γ-hydroxybutyric acid(P=0.008),epinephrine(P=0.030),and dopamine(P=0.047)levels were significantly higher in tongue-rolling groups than in the CON group.Cortisol levels and tongue-rolling frequency had a moderate positive correlation(linearly r=0.363).With the increase in tongue-rolling frequency,the rumen pH decreased first and then increased(P=0.013),comparing to the CON group.HT cows had significantly less food time than CON cows(P=0.035).The frequency of tongue-rolling had a moderate negative relationship with rumination time(r=-0.384)and food time(r=-0.492).Conclusions The tongue-rolling behaviour is considered as a passive coping mechanism,as the stress response in cows with high tongue-rolling frequency increased.Food intake and rumination activities were all closely related to the occurrence of tongue-rolling behaviour. 展开更多
关键词 General activity Holstein cow Rumen fermentation Stress immunity Tongue rolling
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Mixing trait-based corn(Zea mays L.)cultivars increases yield through pollination synchronization and increased cross-fertilization
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作者 Hongping Li Kui Liu +8 位作者 Zhibin Li Moubiao Zhang Yongen Zhang Shuyan Li Xiuling Wang Jinlong Zhou Yali Zhao Tianxue Liu Chaohai Li 《The Crop Journal》 SCIE CSCD 2023年第1期291-300,共10页
Abiotic stress such as high temperature at flowering is one of many conditions reducing yield of corn(Zea mays L.).Mixing corn cultivars with diverse functional traits increases within-crop diversity and provides a po... Abiotic stress such as high temperature at flowering is one of many conditions reducing yield of corn(Zea mays L.).Mixing corn cultivars with diverse functional traits increases within-crop diversity and provides a potential means of mitigating yield losses under stress conditions.We conducted a three-year field study to investigate the effects of cultivar mixtures on kernel setting rate,pollen sources,and yield.This study consisted of six treatments,including two high temperature-tolerant(HTT)monocrops of WK702 and DH701,two high temperature-sensitive(HTS)monocrops of DH605 and DH662,and two HTT–HTS mixtures of WK702-DH605 and DH701-DH662.The anthesis–silking interval(ASI)was 0.9–1.6 days shorter in mixtures than in monocrops.Kernel setting rate was increased in mixtures(86.4%–88.7%)compared with those in monocrops(74.7%–84.1%)as a result of synchrony and complementarity of pollination.Grain yields of the HTT–HTS mixtures increased by 13.3%–18.7%,equivalent to 1169 to1605 kg ha^(-1),in comparison with HTS corn monocrops.The results of SSR markers showed that crossfertilization percentage in corn cultivar mixtures ranged from 29.3%to 47.8%,partially explaining yield improvement.Land equivalent ratio(LER)was 1.12 for corn mixtures and the partial land equivalent ratio(e.g.,>0.5)showed the complementary benefits in corn mixtures.The results indicated that mixing corn cultivars with diverse flowering and drought-tolerance traits increased yields via pollination synchrony. 展开更多
关键词 Cultivar heterogeneity Cultivar mixture Flowering trait synchronization Fertilization complementarity Kernel set
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