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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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Import/Export of China Crude Oil & Oil Products in 1998
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《China Oil & Gas》 CAS 1999年第1期62-62,共1页
关键词 import/export of China Crude Oil
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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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China Chamber of Commerce for Import and Export of Machinery and Electronic Products Holds China-Saudi Investment Conference
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《International Understanding》 2023年第4期64-64,共1页
On December 12th,2023,the China-Saudi Investment Conference,co-sponsored by the Ministry of Commerce of the People's Republic of China and the Ministry of Investment of the Kingdom of Saudi Arabia,and organised by... On December 12th,2023,the China-Saudi Investment Conference,co-sponsored by the Ministry of Commerce of the People's Republic of China and the Ministry of Investment of the Kingdom of Saudi Arabia,and organised by the China Chamber of Commerce for Import and Export of Machinery and Electronic Products. 展开更多
关键词 export import SAUDI
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Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method 被引量:1
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作者 Yi-Sheng Hao Zhen Wu +3 位作者 Shen-Shen Gao Rui Qiu Hui Zhang Jun-Li Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期200-215,共16页
Global variance reduction is a bottleneck in Monte Carlo shielding calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This study proposed a grid-AIS m... Global variance reduction is a bottleneck in Monte Carlo shielding calculations.The global variance reduction problem requires that the statistical error of the entire space is uniform.This study proposed a grid-AIS method for the global variance reduction problem based on the AIS method,which was implemented in the Monte Carlo program MCShield.The proposed method was validated using the VENUS-Ⅲ international benchmark problem and a self-shielding calculation example.The results from the VENUS-Ⅲ benchmark problem showed that the grid-AIS method achieved a significant reduction in the variance of the statistical errors of the MESH grids,decreasing from 1.08×10^(-2) to 3.84×10^(-3),representing a 64.00% reduction.This demonstrates that the grid-AIS method is effective in addressing global issues.The results of the selfshielding calculation demonstrate that the grid-AIS method produced accurate computational results.Moreover,the grid-AIS method exhibited a computational efficiency approximately one order of magnitude higher than that of the AIS method and approximately two orders of magnitude higher than that of the conventional Monte Carlo method. 展开更多
关键词 Monte Carlo Global variance reduction Reactor shielding Automatic importance sampling
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基于Null Importance和Stacking模型的知识追踪研究
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作者 梁开迪 张丽华 《中国科技论文在线精品论文》 2024年第2期174-182,共9页
为应对基于游戏的学习平台在知识追踪应用方面的不足,本研究利用Field Day Lab提供的教育游戏用户日志进行深入分析。采用方差法和Null Importance方法对数据集进行降维处理,并结合K折交叉验证与LightGBM算法,建立了一个高效的预测模型... 为应对基于游戏的学习平台在知识追踪应用方面的不足,本研究利用Field Day Lab提供的教育游戏用户日志进行深入分析。采用方差法和Null Importance方法对数据集进行降维处理,并结合K折交叉验证与LightGBM算法,建立了一个高效的预测模型。此外,通过集成Logistic模型,构建起Stacking模型。研究表明,该模型在验证集上的Macro-F1值显著提升至0.699,同时也在测试集上显示出优异的泛化能力。本研究为教育游戏领域的知识追踪提供了创新方法,并为游戏开发与教育实践提供了宝贵参考,支持教育游戏的开发者为学生创造更有效的学习体验。 展开更多
关键词 人工智能 知识追踪 Null importance Stacking集成模型
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An analysis of agarwood trade patterns,historical perspectives,and species identification challenges:repercussions for importing nations
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作者 Zhao-Qi Xie Jun-Yu Xu +1 位作者 Muhammad Rafiq Chun-Song Cheng 《TMR Modern Herbal Medicine》 CAS 2024年第1期1-10,共10页
Background:Agarwood,primarily derived from the Aquilaria and Gyrinops genera,holds significant economic importance.However,there is a lack of comprehensive investigations providing guidance to importing nations regard... Background:Agarwood,primarily derived from the Aquilaria and Gyrinops genera,holds significant economic importance.However,there is a lack of comprehensive investigations providing guidance to importing nations regarding cultivation quantities and expected yields of Agarwood from distinct species.This study aims to address this gap by exploring the historical context and trade evolution of Agarwood,highlighting its global importance,and the challenges associated with securing accurate species information.Method:On-site visits to Agarwood cultivation sites were conducted to gain a nuanced understanding of Aquilaria species and their cultivation requirements.Additionally,a thorough analysis of global export and import data for Agarwood products over the last decade was undertaken.Results:China Mainland emerged as the leading exporter of Agarwood,averaging an annual export value of USD 1 million.India’s substantial exports challenge the prevailing notion of limited Agarwood production within its borders.Hong Kong and Singapore are pivotal distribution hubs,while Hong Kong and Taipei feature prominently as import destinations.Our analysis uncovers anomalies in the representation of Agarwood producers from 2001 to 2008,suggesting potential misclassification of Aquilaria Agarwood as Gyrinops in global export information.These findings underscore the urgency of investigating classification and reporting practices in the Agarwood trade.Furthermore,A.filaria emerges as a notable source,while A.malaccensis is decline in prominence.Conclusion:This study provides crucial insights for policymakers,stakeholders,and industry players seeking to make informed decisions in the Agarwood trade landscape.The results highlight the need for accurate species identification,classification,and reporting practices to ensure sustainable cultivation and trade of Agarwood. 展开更多
关键词 AGARWOOD import and export trends global trade field visits industry analysis
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Identification of Important FPGA Modules Based on Complex Network
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作者 Senjie Zhang Jinbo Wang +3 位作者 Shan Zhou Jingpei Wang Zhenyong Zhang Ruixue Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1027-1047,共21页
The globalization of hardware designs and supply chains,as well as the integration of third-party intellectual property(IP)cores,has led to an increased focus from malicious attackers on computing hardware.However,exi... The globalization of hardware designs and supply chains,as well as the integration of third-party intellectual property(IP)cores,has led to an increased focus from malicious attackers on computing hardware.However,existing defense or detection approaches often require additional circuitry to perform security verification,and are thus constrained by time and resource limitations.Considering the scale of actual engineering tasks and tight project schedules,it is usually difficult to implement designs for all modules in field programmable gate array(FPGA)circuits.Some studies have pointed out that the failure of key modules tends to cause greater damage to the network.Therefore,under limited conditions,priority protection designs need to be made on key modules to improve protection efficiency.We have conducted research on FPGA designs including single FPGA systems and multi-FPGA systems,to identify key modules in FPGA systems.For the single FPGA designs,considering the topological structure,network characteristics,and directionality of FPGA designs,we propose a node importance evaluationmethod based on the technique for order preference by similarity to an ideal solution(TOPSIS)method.Then,for the multi-FPGA designs,considering the influence of nodes in intra-layer and inter-layers,they are constructed into the interdependent network,and we propose a method based on connection strength to identify the important modules.Finally,we conduct empirical research using actual FPGA designs as examples.The results indicate that compared to other traditional indexes,node importance indexes proposed for different designs can better characterize the importance of nodes. 展开更多
关键词 Hardware security FPGA circuits node importance interdependent network
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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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Development of endemicity and conservation importance indices for tropical forests and the floral diversity assessment of Mt.Natoo in Benguet,Philippines
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作者 Johndale Rein T.BULLONG Jim P.SILVERIO +2 位作者 Joanna I.ALAFAG Maricel A.GURON Jones T.NAPALDET 《Journal of Mountain Science》 SCIE CSCD 2024年第3期786-804,共19页
The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using tradition... The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary ones.This shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the species.This study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the species.These indices were applied to Mt.Natoo,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of 42.90.Comparing these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower values.Thus,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical forests.Additionally,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in Mt.Nato-o.Majority are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate climate.These are important baseline information for conservation plans and monitoring of tropical mossy forests. 展开更多
关键词 Endemicity index Conservation importance index Cordillera Central Range Floristic element Jaccard Index of Similarity
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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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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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Beyond statistical significance:Embracing minimal clinically important difference for better patient care
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作者 Naveen Jeyaraman Madhan Jeyaraman +2 位作者 Swaminathan Ramasubramanian Sangeetha Balaji Sathish Muthu 《World Journal of Methodology》 2025年第1期33-41,共9页
The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the p... The minimal clinically important difference(MCID)represents a pivotal metric in bridging the gap between statistical significance and clinical relevance,addressing the direct impact of medical interventions from the patient's perspective.This comprehensive review analyzes the evolution,applications,and challenges of MCID across medical specialties,emphasizing its necessity in ensuring that clinical outcomes not only demonstrate statistical significance but also offer genuine clinical utility that aligns with patient expectations and needs.We discuss the evolution of MCID since its inception in the 1980s,its current applications across various medical specialties,and the methodologies used in its calculation,highlighting both anchor-based and distribution-based approaches.Furthermore,the paper delves into the challenges associated with the application of MCID,such as methodological variability and the interpretation difficulties that arise in clinical settings.Recommendations for the future include standardizing MCID calculation methods,enhancing patient involvement in setting MCID thresholds,and extending research to incorporate diverse global perspectives.These steps are critical to refining the role of MCID in patient-centered healthcare,addressing existing gaps in methodology and interpretation,and ensuring that medical interventions lead to significant,patient-perceived improvements. 展开更多
关键词 Minimal clinically important difference Patient-centered care Clinical relevance Global health
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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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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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The Importance of Breathing Training in Folk Dance Teaching
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作者 Xiaowei Sun 《Journal of Contemporary Educational Research》 2024年第4期187-192,共6页
The importance of breathing training in dance teaching is reflected in the two aspects of enhancing the quality of dance movements and sublimating the connotation of dance movements.For example,high-quality breathing ... The importance of breathing training in dance teaching is reflected in the two aspects of enhancing the quality of dance movements and sublimating the connotation of dance movements.For example,high-quality breathing can help performers complete the dance movements and improve the coordination of the movements;at the same time,the unique body rhythm formed by breathing can strengthen the visual effect of the performance and convey its spirit and soul to the audience.This requires folk dance teachers to carry out relevant training and teaching activities based on the categories and skills of dance breathing,such as changing students’ideological cognition,developing periodic breathing training courses,providing personalized guidance to students,and allowing students to adjust their learning and practice methods in the evaluation. 展开更多
关键词 Folk dance teaching Breathing training importANCE Training methods
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