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Does Green Food Certification promote agri-food export quality?Evidence from China
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作者 Ping Wei Hongman Liu +1 位作者 Chaokai Xu Shibin Wen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1061-1074,共14页
The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with... The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match China's industry-level data of Green Food Certification with its HS6-digit export data of agri-food products to quantify the impact of Green Food Certification on export quality. We identify the significant and positive effect of Green Food Certification on export quality. The 2SLS estimation based on instrumental variables and a range of robustness checks confirm the validity and robustness of the benchmark conclusions. Further analysis discloses that Green Food Certification improves export quality by raising agricultural production efficiency and brand premiums. Heterogeneity analysis shows that the effect of Green Food Certification varies across regions, notably improving the quality of agri-food products exported to developed regions and regions with high levels of import supervision. Furthermore, among various product types, Green Food Certification significantly improves the export quality of primary products and products vulnerable to non-tariff measures. The above findings could guide the future development of agri-food quality certification systems, potentially leading to a transformation and promotion of the agri-food trade. 展开更多
关键词 Green Food Certification agri-food products green transformation export quality food labeling
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Impact of BRICS Trade Facilitation on China's Exports Using Cross-Border E-Commerce
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作者 Longling LI Kaimei CHEN Zijian LONG 《Asian Agricultural Research》 2024年第5期1-7,共7页
With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important forc... With the rapid growth of the global digital economy, cross-border e-commerce, as an emerging form of trade, has gradually become a powerful engine to promote the development of global trade. BRICS is an important force in the global economy, and the progress of the BRICS countries' trade facilitation level has an important impact on the global trade environment. This paper conducts an in-depth study of the dynamic changes in BRICS trade facilitation from 2013 to 2022, and uses an extended gravity model to analyze the specific impact of this change on China's exports using cross-border e-commerce. The results show that although the BRICS countries have made some progress in trade facilitation, the overall level still needs to be improved, and there are obvious differences among member countries. However, the improvement of trade facilitation among BRICS countries has undoubtedly brought significant positive effects to China's exports using cross-border e-commerce. 展开更多
关键词 Trade facilitation BRICS Cross-border e-commerce export trade
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Enhanced Deep Reinforcement Learning Strategy for Energy Management in Plug-in Hybrid Electric Vehicles with Entropy Regularization and Prioritized Experience Replay
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作者 Li Wang Xiaoyong Wang 《Energy Engineering》 EI 2024年第12期3953-3979,共27页
Plug-in Hybrid Electric Vehicles(PHEVs)represent an innovative breed of transportation,harnessing diverse power sources for enhanced performance.Energy management strategies(EMSs)that coordinate and control different ... Plug-in Hybrid Electric Vehicles(PHEVs)represent an innovative breed of transportation,harnessing diverse power sources for enhanced performance.Energy management strategies(EMSs)that coordinate and control different energy sources is a critical component of PHEV control technology,directly impacting overall vehicle performance.This study proposes an improved deep reinforcement learning(DRL)-based EMSthat optimizes realtime energy allocation and coordinates the operation of multiple power sources.Conventional DRL algorithms struggle to effectively explore all possible state-action combinations within high-dimensional state and action spaces.They often fail to strike an optimal balance between exploration and exploitation,and their assumption of a static environment limits their ability to adapt to changing conditions.Moreover,these algorithms suffer from low sample efficiency.Collectively,these factors contribute to convergence difficulties,low learning efficiency,and instability.To address these challenges,the Deep Deterministic Policy Gradient(DDPG)algorithm is enhanced using entropy regularization and a summation tree-based Prioritized Experience Replay(PER)method,aiming to improve exploration performance and learning efficiency from experience samples.Additionally,the correspondingMarkovDecision Process(MDP)is established.Finally,an EMSbased on the improvedDRLmodel is presented.Comparative simulation experiments are conducted against rule-based,optimization-based,andDRL-based EMSs.The proposed strategy exhibitsminimal deviation fromthe optimal solution obtained by the dynamic programming(DP)strategy that requires global information.In the typical driving scenarios based onWorld Light Vehicle Test Cycle(WLTC)and New European Driving Cycle(NEDC),the proposed method achieved a fuel consumption of 2698.65 g and an Equivalent Fuel Consumption(EFC)of 2696.77 g.Compared to the DP strategy baseline,the proposed method improved the fuel efficiency variances(FEV)by 18.13%,15.1%,and 8.37%over the Deep QNetwork(DQN),Double DRL(DDRL),and original DDPG methods,respectively.The observational outcomes demonstrate that the proposed EMS based on improved DRL framework possesses good real-time performance,stability,and reliability,effectively optimizing vehicle economy and fuel consumption. 展开更多
关键词 plug-in hybrid electric vehicles deep reinforcement learning energy management strategy deep deterministic policy gradient entropy regularization prioritized experience replay
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Export Competitiveness and Sustainable Development of the Ukrainian Timber Industry
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作者 Anastasiia Shapiro 《Open Journal of Applied Sciences》 2024年第10期2777-2789,共13页
This paper conducts a comprehensive analysis of the export dynamics within the Ukrainian timber industry, emphasizing its pivotal role in the national economy. The study begins by outlining the research objectives, co... This paper conducts a comprehensive analysis of the export dynamics within the Ukrainian timber industry, emphasizing its pivotal role in the national economy. The study begins by outlining the research objectives, context, and innovative methodologies, setting the stage for a deep dive into the theoretical underpinnings of sustainable and competitive trade. It explores Ukraine’s rich forest biodiversity across varied vegetation zones and its geopolitical significance. Detailed evaluations of forest resource management, policy frameworks, and institutional support form the core of the analysis. Challenges such as imbalanced export structures and legal inconsistencies are critically examined. The research employs trade gravity models and competitive indicators like the Revealed Comparative Advantage (RCA) and Market Share (MS) to assess factors influencing exports and to forecast potential growth areas. The findings inform strategic recommendations aimed at enhancing export capacity through market diversification, brand development, and legal stability. The conclusion highlights the need for strategic interventions to harness Ukraine’s timber resources sustainably, balancing economic gains with environmental stewardship. 展开更多
关键词 Ukrainian Timber Industry export Dynamics export Competitiveness Sustainable Trade Forest Resource Management
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Changes in calcium accumulation and utilization efficiency and their impact on recycling,immobilization,and export across the oil palm cycle
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作者 Ismael de Jesus Matos Viégas Luma Castro de Souza +4 位作者 Eric Victor de Oliveira Ferreira Milton Garcia Costa Glauco André dos Santos Nogueira Vitor Resende do Nascimento Candido Ferreira de Oliveira Neto 《Oil Crop Science》 CSCD 2024年第3期143-150,共8页
Effective calcium(Ca)management is crucial for optimizing oil palm cultivation and enhancing crop yield.This study aimed to gain insights into the dynamics of Ca concentration,accumulation,exportation,immobilization,a... Effective calcium(Ca)management is crucial for optimizing oil palm cultivation and enhancing crop yield.This study aimed to gain insights into the dynamics of Ca concentration,accumulation,exportation,immobilization,and recycling in various oil palm organs relative to plant age.The experiment was conducted at the Agropalma enterprise site in the northeastern region of Para State,Brazil,evaluating seven plant age treatments:2,3,4,5,6,7,and 8 years old.Employing a completely randomized design with four replications.The results demonstrated an age-related increase in Ca concentration in petioles,rachis,arrows,male inflorescences,peduncles,and fruits.Furthermore,Ca accumulation exhibited an upward trend in all organs with progressing plant age.Notably,the study revealed an enhanced Ca use efficiency across all plant organs in correlation with the age of oil palm cultivation.These findings underscore the dynamic nutritional demands of oil palm,influencing Ca immobilization,cycling,and export throughout its developmental stages. 展开更多
关键词 Elaeis guineensis Jacq Ca cycling Ca export Ca immobilization Ca use efficiency Plant nutrition AMAZON
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Building the ARIMA Model for Forecasting the Production of Vietnam’s Coffee Export
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作者 Duy Quang Phung Quoc Thang Trinh +4 位作者 Quang Truong Do Ngan Giang Nguyen Van Ha Nguyen Gia Khiem Ngo Thi Minh Ngoc Tran 《Journal of Applied Mathematics and Physics》 2024年第4期1237-1246,共10页
Coffee is a significant industry, accounting for 3% of Vietnam’s GDP, with annual export turnover consistently exceeding USD 3 billion. Despite global economic challenges affecting purchasing power at various times, ... Coffee is a significant industry, accounting for 3% of Vietnam’s GDP, with annual export turnover consistently exceeding USD 3 billion. Despite global economic challenges affecting purchasing power at various times, Vietnam’s coffee exports in December 2023 continued to surge, reaching the highest level in the past 9 months at 190,000 tons, a 59.3% increase compared to November 2023, but still a slight 3.5% decrease from the same period last year. The export turnover reached USD 538 million, a 51% increase from November 2023 and a 26.4% increase from the same period last year. Therefore, forecasting the coffee export volume holds significant importance for coffee producers nationwide. This research employs the Box-Jenkins method to construct an ARIMA model for forecasting Vietnam’s coffee export volume based on annual data published by the General Statistics Office. Results indicate that among the models considered, the ARIMA(1, 1, 2) model is the most suitable. The study also provides short-term forecasts for Vietnam’s coffee export volume. However, the current model is limited to forecasting and is not yet optimized, as the assumed linearity in the model is a simplification. 展开更多
关键词 ARIMA Forecasting Coffee export Volume Data Science
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Analysis of the Impact of Technical Trade Barriers on the Export of Toys-Based on Analysis of Zhejiang,China
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作者 LIU Ningning CHEN Xiaoxi 《Chinese Business Review》 2024年第1期37-46,共10页
Technical barriers to trade,as a non-tariff barrier,have an increasing impact on the international market.As a major province in toy exports,Zhejiang Province’s toy export trade is therefore greatly hindered.This art... Technical barriers to trade,as a non-tariff barrier,have an increasing impact on the international market.As a major province in toy exports,Zhejiang Province’s toy export trade is therefore greatly hindered.This article aims to explore the impact of technical trade barriers on toy exports in Zhejiang Province and analyze countermeasures.Through literature review and some empirical analysis,it is found that technical trade barriers have greatly promoted the development of Zhejiang’s toy industry;however,they have also subjected it to impacts and pressures such as cost and technology.In response to the impact of technical trade barriers on toy exports,this article proposes corresponding countermeasures to avoid such barriers:firstly,establish a quality management system that complies with export product regulations to ensure that the products produced can meet international requirements and standards;secondly,reduce dependence on overseas markets;then enhance one’s own technology,and strengthen product innovation,in order to enhance the international competitiveness of the product and oneself;in addition,we should also explore diversified markets and expand the sales channels and coverage of our products. 展开更多
关键词 technical trade barriers Zhejiang Province export of toys countermeasure analysis
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Mysterious Exporter for Brassinosteroid First Identified
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《Bulletin of the Chinese Academy of Sciences》 2024年第1期50-51,共2页
It is impossible for plants to grow and reproduce without being regulated by phytohormones.One of the phytohormones is the brassinosteroid(BR)hormones,also named as the sixth phytohormone.
关键词 export impossible sixth
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China:In the fourth quarter of 2023,exports of yarn and fabric to ASEAN ceased declining and rebounded
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《China Textile》 2024年第1期22-23,共2页
On January 8th,the China Chamber of Commerce for Import and Export of Textiles released data showing that in the fourth quarter,China’s textile and clothing exports gradually stabilised.The proportion of intermediate... On January 8th,the China Chamber of Commerce for Import and Export of Textiles released data showing that in the fourth quarter,China’s textile and clothing exports gradually stabilised.The proportion of intermediate exports in textile and clothing exports continued to rise,providing a new impetus for the substantial expansion of exports to traditional markets and international supply chain cooperation. 展开更多
关键词 export QUARTER FOURTH
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China's rare earth import and export analysis in the 1st half of 2024
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作者 Zhang Wencan 《China Rare Earth Information》 2024年第3期11-14,共4页
1.Export situation from January to June 20241.1 Overall export situation of rare earth products Export value of rare earth products showed a wholistic down trend affected by the continuousdecline in rare earth prices ... 1.Export situation from January to June 20241.1 Overall export situation of rare earth products Export value of rare earth products showed a wholistic down trend affected by the continuousdecline in rare earth prices in the first half year,however,export volume increased.According to statistics from the General Administration of Customs,from January to June 2024,China's cumulative export of rare earth products was 29,095 tons,an increase of 11%year-on-year,with a cumulative export value of 256 million US dollars,a decrease of 43% year-on-year,Figure 1. 展开更多
关键词 export FIGURE DOLLAR
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Research on the Threshold Effect of China’s Pharmaceutical Export Trade on Internal and External R&D Investment
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作者 Qiao Jiahui Song Yu +1 位作者 Gong Jingran Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第2期135-146,共12页
Objective To study the threshold effect of export trade on internal and external R&D investment in China’s pharmaceutical industry,and to provide reference for some pharmaceutical enterprises to improve the inves... Objective To study the threshold effect of export trade on internal and external R&D investment in China’s pharmaceutical industry,and to provide reference for some pharmaceutical enterprises to improve the investment.Methods The panel data of pharmaceutical industry in 25 provinces and cities in China from 2009 to 2019 were selected to conduct empirical analysis by establishing a threshold regression model,and a better export trade interval was obtained.Results and Conclusion There is a threshold value for the effect of new product export on both internal and external R&D expenditures,and the threshold values are 845.2788 million yuan and 318.4198 million yuan,respectively.There is a single threshold effect of export trade on both internal and external R&D investment in China’s pharmaceutical industry,and the effect of export trade on internal and external R&D investment changes from negative to positive as the export trade develops from low to high. 展开更多
关键词 pharmaceutical industry threshold effect export trade R&D investment
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Plug-in混合动力汽车能量管理策略优化设计 被引量:15
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作者 张博 李君 +3 位作者 高莹 杨世春 杨成宏 陈华艳 《农业机械学报》 EI CAS CSCD 北大核心 2009年第9期20-25,共6页
应用PSAT前向仿真软件及矩阵分割全局优化算法,对并联式Plug-in混合动力汽车(PHEV)在不同电能消耗续驶里程(CDR)下的能量管理策略进行了优化设计研究。结果表明:PHEV电能消耗续驶里程越大,优化控制参数对整车经济性影响越小;小CDR优化... 应用PSAT前向仿真软件及矩阵分割全局优化算法,对并联式Plug-in混合动力汽车(PHEV)在不同电能消耗续驶里程(CDR)下的能量管理策略进行了优化设计研究。结果表明:PHEV电能消耗续驶里程越大,优化控制参数对整车经济性影响越小;小CDR优化控制参数的整车平均经济性能好于大CDR优化控制参数;利用优化设计得到的PHEV能量管理策略可以使整车平均等价油耗降至2.70 L/(100 km),相对于原型车经济性提高了近58%。 展开更多
关键词 plug-in混合动力汽车 能量管理策略 优化 仿真
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用Plug-in实现对PDF文件的信息提取 被引量:16
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作者 李贵林 李建中 杨艳 《计算机应用》 CSCD 北大核心 2003年第2期110-112,共3页
利用AdobeAcrobat提供的编程接口编写Plug in插件,实现对PDF文件信息的提取。
关键词 PDF文件 信息提取 程序设计 plug-in插件
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Plug-in结构应用程序设计 被引量:18
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作者 刘毅 陈慧蓉 荣钢 《计算机应用》 CSCD 北大核心 2002年第4期9-11,14,共4页
插件 (Plug in)结构使软件可以动态地寻找和加载特定的代码模块 ,因此被越来越广泛地采用。文中分析了Plug in程序应当具有的主要特性 ,介绍了运用标准DLL方式和COM标准两种方式实现Plug in结构的界面的方法 。
关键词 程序设计 应用程序 plug-in结构 代码模块 计算机
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Plug-in混合动力汽车动力总成优化设计研究 被引量:11
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作者 张博 李君 +2 位作者 杨世春 高莹 尹雪峰 《汽车工程》 EI CSCD 北大核心 2009年第7期592-596,共5页
应用PSAT前向仿真软件,建立了双离合器式并联PHEV仿真模型。在确定了PHEV整车性能约束条件并对动力总成主要部件进行了成本分析之后,对不同全电力续驶里程和动力电池类型的PHEV动力总成进行了优化。结果表明:动力电池设计容量对整车成... 应用PSAT前向仿真软件,建立了双离合器式并联PHEV仿真模型。在确定了PHEV整车性能约束条件并对动力总成主要部件进行了成本分析之后,对不同全电力续驶里程和动力电池类型的PHEV动力总成进行了优化。结果表明:动力电池设计容量对整车成本影响最大,而它主要取决于所要求的全电力续驶里程;随着所要求的全电力续驶里程的增大,所需电机最大输出功率升高,而发动机最大输出功率则降低。 展开更多
关键词 plug-in混合动力汽车 动力总成 优化设计 PSAT仿真软件
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Plug-in混合动力汽车动力系统参数匹配 被引量:11
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作者 赵又群 李佳 《应用基础与工程科学学报》 EI CSCD 2011年第3期459-465,共7页
以并联型Plug-in混合动力电动汽车(PHEV)为研究对象,提出了其动力驱动系统参数匹配的原则和实施方法.采用该方法对某型轿车动力总成参数进行了匹配,使用电动汽车仿真软件ADVISOR对整车性能进行仿真计算.仿真结果表明:Plug-in混合动力轿... 以并联型Plug-in混合动力电动汽车(PHEV)为研究对象,提出了其动力驱动系统参数匹配的原则和实施方法.采用该方法对某型轿车动力总成参数进行了匹配,使用电动汽车仿真软件ADVISOR对整车性能进行仿真计算.仿真结果表明:Plug-in混合动力轿车动力性与原车相当,经济性与原车相比有很大提高,达到预期开发目标. 展开更多
关键词 plug-in混合动力汽车 动力总成 参数匹配 仿真
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大型过程建模的Import/Export解决方案 被引量:3
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作者 张莉 王文 《计算机工程与应用》 CSCD 北大核心 2001年第12期23-26,共4页
文章分析了大型复杂过程的建模需求,基于已研发的企事业过程建模系统EPMS,提出了将Import/Export技术用于大型过程建模的解决方案,通过过程模型的拆分和组装,从而支持过程模型的多人员、异地并行建模模式和过程重用。
关键词 大型模型建模 Import/export 软件工程 可视化
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Status quo and Countermeasures of Tea Export Trade of China 被引量:4
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作者 桂燕玲 《Agricultural Science & Technology》 CAS 2015年第7期1527-1530,1551,共5页
The research analyzed status quo of Chinese tea export, including export scale, exporting countries and regions, product structure, explored factors affecting tea export, and detailed international trade development o... The research analyzed status quo of Chinese tea export, including export scale, exporting countries and regions, product structure, explored factors affecting tea export, and detailed international trade development of Chinese teas. On basis of global politics and economic situations, the research proposed new thoughts and of global trades of Chinese teas with application of the Belt and Road Initiative strategy. 展开更多
关键词 TEA Chinese tea export International tea trade Status quo
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基于plug-in的网络漏洞扫描系统 被引量:1
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作者 刘宇东 《信息网络安全》 2003年第12期49-50,共2页
计算机网络最大的优势在于资源共享和通信,与此同时也必然会存在各种各样的安全漏洞,及时发现并填补这些漏洞是当前网络安全工作的一个重要任务。本文分析了漏洞扫描的关键技术,提出基于Plug-in的网络漏洞扫描系统的设计和实现。
关键词 网络漏洞扫描系统 计算机网络 网络安全 plug-in 软件模块 防火墙
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利用Plug-in技术扩展应用程序的Web应用 被引量:1
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作者 赵黔莉 《微型机与应用》 2004年第2期33-35,共3页
讨论Plug-in的基本原理和开发方法,实现了一个H.263解码器的插件,并研究了如何把应用程序通过Plug-in技术嵌入浏览器中。
关键词 plug-in H.263解码器 插件 浏览器 WEB应用 MIME
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