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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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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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Distribution,species richness,and relative importance of different plant life forms across drylands in China
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms Relative importance Species richness THRESHOLD
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The First Imported Case of Lassa Fever in China-Implications for Global Health Surveillance
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作者 Qiyong Liu 《Biomedical and Environmental Sciences》 2025年第3期277-278,共2页
Lassa fever(LF)is an acute viral hemorrhagic disease caused by Lassa virus(LASV)[1].LASV is transmitted to humans primarily through direct contact with infected Mastomys rodents,or items polluted by infected rodents[2... Lassa fever(LF)is an acute viral hemorrhagic disease caused by Lassa virus(LASV)[1].LASV is transmitted to humans primarily through direct contact with infected Mastomys rodents,or items polluted by infected rodents[2].LF is difficult to diagnose without laboratory tests because of its various symptoms,ranging from no symptoms to multiple organ failure and death[2].West Africa is the traditionally endemic regions for LF,with confirmed and sporadic outbreaks reported in countries,such as Nigeria,Burkina Faso and Guinea[2].LF cases have also been detected in some non-endemic regions due to international travels[3,4],for example,the United Kingdom found LF imported cases from Mali[5].This indicates that the countries are exposed to imported risks of LF due to the globalization.The recent publication[6]reported the first imported cases of LF in China,providing important insights into the understanding and control of the emerging infectious disease. 展开更多
关键词 importED TRAVEL traditionally
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Laboratory Diagnosis and Molecular Epidemiological Characterization of the First Imported Case of Lassa Fever in China
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作者 Yuliang Feng Wei Li +11 位作者 Mingfeng Jiang Hongrong Zhong Wei Wu Lyubo Tian Guo Chen Zhenhua Chen Can Luo Rongmei Yuan Xingyu Zhou Jiandong Li Xiaorong Yang Ming Pan 《Biomedical and Environmental Sciences》 2025年第3期279-289,共11页
Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the preven... Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the prevention and control of LF.Methods Samples of cerebrospinal fluid(CSF),blood,urine,saliva,and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection.Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus.Results LASV was detected in the patient’s CSF,blood,and urine,while all samples from close contacts and the environment tested negative.The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone.The variability in the glycoprotein complex(GPC)among different strains ranged from 3.9%to 15.1%,higher than previously reported for the seven known lineages.Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes,increasing strain diversity and potentially impacting immune response.Conclusion The case was confirmed through nucleotide detection,with no evidence of secondary transmission or viral spread.The LASV strain identified belongs to lineage IV,with broader GPC variability than previously reported.Mutations in the immune-related sites of GPC may affect immune responses,necessitating heightened vigilance regarding the virus. 展开更多
关键词 Lassa fever The first imported case Laboratory diagnosis Epidemiological characterization
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Research on a Monte Carlo global variance reduction method based on an automatic importance sampling method 被引量:2
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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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An Experimental Study on the Performance of Storage Pulverizing System after Renovation of Importing Hot Air
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作者 Guoqing Han Hongqi Wei +1 位作者 Chang-zheng He Ying-hui Li 《Energy and Power Engineering》 2013年第4期330-336,共7页
A thermal power plant of Sinopec has 9 boilers, which generally have problems of high exhaust gas temperature and high flying ash carbon content. In order to improve the adaptability of coals, the stability of coal po... A thermal power plant of Sinopec has 9 boilers, which generally have problems of high exhaust gas temperature and high flying ash carbon content. In order to improve the adaptability of coals, the stability of coal powder ignition, the burn-off rate of pulverized coals and the boiler efficiency, a series of renovation projects about importing hot air into mill exhauster are proposed. For the sake of verifying the renovation effects, an efficiency performance test is conducted on the renovated #5 boiler. The test result shows that the boiler heat efficiency has improved by 0.4% and it operates more safely and reliably after the renovation. At last, this paper recommends an optimized operation mode. 展开更多
关键词 STORAGE Pulverizing System importing HOT AIR RENOVATION PERFORMANCE Test Operation Optimization
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The Culture Importing In English Language Teaching
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作者 Yin Jiling 《International Journal of Technology Management》 2014年第4期67-69,共3页
With the advancement of economic globalization, our country needs more and more English talents with international vision. University English Language Teaching is not just limited to listening, speaking, reading and w... With the advancement of economic globalization, our country needs more and more English talents with international vision. University English Language Teaching is not just limited to listening, speaking, reading and writing, but also develops students 'intercultural communicative competence, so it requires teachers to import culture in the teaching process and cultivate the students' cultural awareness. 展开更多
关键词 English language teaching cultural import importANCE measures
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Heterogeneous Firms in Importing: Theory and Evidence from China
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作者 Yuting Chen 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2015年第2期301-334,共34页
In this study, I explore the effects of the financial status of firms on its decisions to import. The import decision is reflected in various aspects, such as whether to import or buy from home market; what types of g... In this study, I explore the effects of the financial status of firms on its decisions to import. The import decision is reflected in various aspects, such as whether to import or buy from home market; what types of goods to import, etc. A novelty of this analysis is that I distinguish between ordinary trade and processing trade, which involves importing inputs to be assembled and re-exported. Several novel patterns emerge. Firstly, a firm's financial status, especially its liquidity, significantly influences its decisions to import. Secondly, regional financial development also has a significantly affect importing decisions. However, a firm's creditworthiness and regional factors work independently (i.e., regional financial development does not alleviate a firm's credit constraints). The findings yield implications for developing economies which demand technological spillovers from advanced markets and those which maintain large trade surpluses with the developed economies. 展开更多
关键词 heterogeneous firms import credit constraints
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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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Discussion on Question of Importing Large-scale Equipment from Other Countries by Installment
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作者 DUAN Li-wei LU Zhong -hai +4 位作者 SHANG Guo-xin QI liang-xin WANG Ming -xue SUN Feng-lei(Intrument Sechon, Zhujinag Hospital, First Military Surgeon University, Guangzhou, 510282, China Education Guaranteeing Department, First Surgeon University, Guangzhou, 5 《International Journal of Plant Engineering and Management》 1999年第2期469-474,共6页
Successful cases have not been rare, that is to import funds accelerate hospital building by means of raising funds, borrowing, renting, jointing, and so on. The same characteristics is raising money at first and then... Successful cases have not been rare, that is to import funds accelerate hospital building by means of raising funds, borrowing, renting, jointing, and so on. The same characteristics is raising money at first and then working, and the investor will earn high proportional benefits. 'Importing funds' has solved some practical problems, but it also causes some negative effects, such as difficulty in management, being difficult to work, inequitable benefit allocation, little benefits earned by the hospital, a big venture, and so on.By means of installment, the hospital has imported much equipment, such as very expensive Magnetic Resonating Instrument (MRI), spiral CT, straight accelerator, ECT and so on. Connecting with practice, the authors has analyzed objectively the profits and the harm of importing equipment by installment. There are four reasons for applying installment: firstly, it solves the problem of shortage of funds of the hospital; secondly, it efficiently avoids the inconvenience resulted from the management by both jointing sides together; thirdly, it raises the investing earnings of the hospital; finally, it is advantages which are as follows. Importing large-scale foreign equipment from abroad by installment has not been popular in the native hospital, and there are not relatively regular and ripe rules to be followed. Moreover, because effective institution is required to act as an economic guarantor, an extra content of work will, be added to practice.The authors prefer that attentions should be paid to the five aspects in importing equipment by means of installment; selecting the suitable importing project, selecting a favorable cooperating partner and deciding suitable cooperating items; selecting an excellent company or institution to guarantee for the hospital, and grasping the practice of the contract. 展开更多
关键词 HOSPITAL importing equipment PURCHASING INSTALLMENT
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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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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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Importance-Weighted Transfer Learning for Fault Classification under Covariate Shift
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作者 Yi Pan Lei Xie Hongye Su 《Intelligent Automation & Soft Computing》 2024年第4期683-696,共14页
In the process of fault detection and classification,the operation mode usually drifts over time,which brings great challenges to the algorithms.Because traditional machine learning based fault classification cannot d... In the process of fault detection and classification,the operation mode usually drifts over time,which brings great challenges to the algorithms.Because traditional machine learning based fault classification cannot dynamically update the trained model according to the probability distribution of the testing dataset,the accuracy of these traditional methods usually drops significantly in the case of covariate shift.In this paper,an importance-weighted transfer learning method is proposed for fault classification in the nonlinear multi-mode industrial process.It effectively alters the drift between the training and testing dataset.Firstly,the mutual information method is utilized to perform feature selection on the original data,and a number of characteristic parameters associated with fault classification are selected according to their mutual information.Then,the importance-weighted least-squares probabilistic classifier(IWLSPC)is utilized for binary fault detection and multi-fault classification in covariate shift.Finally,the Tennessee Eastman(TE)benchmark is carried out to confirm the effectiveness of the proposed method.The experimental result shows that the covariate shift adaptation based on importance-weight sampling is superior to the traditional machine learning fault classification algorithms.Moreover,IWLSPC can not only be used for binary fault classification,but also can be applied to the multi-classification target in the process of fault diagnosis. 展开更多
关键词 Covariate shift adaption nonlinear multi-mode process importance weight sampling multi-fault classification
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An Analysis of Innovative Contributions to the Important Discourse on the Development of New Quality Productivity
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作者 Yao Hao Jie Wu 《Journal of Contemporary Educational Research》 2024年第6期135-141,共7页
The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality product... The discourse on developing high-quality productivity marks a significant theoretical innovation,which is conducive to the modernization and sinicization of Marxism.It refines our understanding of“new quality productivity,”defining it as an advanced form driven by innovation,embodying“high technology,efficiency,and quality,”with the aim of comprehensively enhancing productivity.It elucidates the necessity of cultivating such forces,asserting that they are crucial for achieving high-quality development,securing a leading position in global technology,and fulfilling the aspirations for a better life.Moreover,it outlines a new implementation route,emphasizing strategies such as fostering technological autonomy,nurturing emerging industries,integrating education and talent in technology,adopting a“build through challenges”approach,adjusting solutions locally,and providing categorized guidance,all of which are based on the ongoing comprehensive reforms. 展开更多
关键词 New quality productivity Basic connotation important discourse Realistic approach Innovative contributions
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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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Salience theory value spillovers between China’s systemically important banks:evidence from quantile connectedness
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作者 Xiaoye Jin 《Financial Innovation》 2024年第1期3028-3066,共39页
Analyzing the interdependencies among financial institutions is critical for designing systemic risk monitoring mechanisms;however,most existing research focuses on the first moment of the return distribution,which fa... Analyzing the interdependencies among financial institutions is critical for designing systemic risk monitoring mechanisms;however,most existing research focuses on the first moment of the return distribution,which falls into the conventional models of choice under risk.Previous literature has observed the scarcity of investors’attention and processing power,which makes the traditional theory of choice under risk more vulnerable and brings the salience theory that accommodates investors’cognitive limitations to our attention.Motivated by evidence of salience theory value(STV)containing unique information not captured by traditional higher-order moments,we employ a quantile connectedness approach to examine the STV interconnectedness of China’s systemically important banks(C-SIBs).The quantile approach allows us to uncover the dynamic STV interconnectedness of C-SIBs under normal,bearish,and bullish market conditions and is well-suited to extreme risk problems.Our results show that the C-SIBs system is asymmetrically interconnected across quantiles and at higher levels under bullish than bearish market conditions.Principally,a bank’s performance in the C-SIBs system depends on its systemic importance and market conditions.Furthermore,the comparative analysis indicates that STV could provide more information than higher-order moments in capturing the dynamic change in the C-SIBs system and detecting some market events more precisely.These results have important implications for policymakers and market participants to formulate regulatory policy and design risk management strategies. 展开更多
关键词 Salience theory value Extreme spillovers Quantile connectedness China's systemically important banks
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《中国矿产地质志》研编与新一轮找矿突破行动建议--“庆祝陈毓川院士九十华诞暨从事地质工作70周年”专辑特邀主编寄语
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作者 王登红 《地球学报》 北大核心 2025年第1期2-7,共6页
矿产资源是经济社会发展的重要物质基础,矿产资源勘查开发事关国计民生和国家安全。为保障国家矿产资源安全,当前全国上下正在全面组织实施新一轮找矿突破战略行动,以推动加强国内重要的战略性矿产资源的勘探开发和增储上产,从源头上完... 矿产资源是经济社会发展的重要物质基础,矿产资源勘查开发事关国计民生和国家安全。为保障国家矿产资源安全,当前全国上下正在全面组织实施新一轮找矿突破战略行动,以推动加强国内重要的战略性矿产资源的勘探开发和增储上产,从源头上完善战略性矿产资源探采供储销统筹和衔接体系。为了进一步摸清我国资源家底,全面反映矿产勘查成果和成矿规律,以陈毓川院士为首的科研团队于2012年起牵头组织实施了新中国第一部《中国矿产地质志》研编工作,截至目前,研编工作取得重大进展,完成了200多部志书评审验收,其中,正式出版发行了88部。在《地球学报》编辑部的大力支持下,本专辑共汇集了18篇论文,内容主要涉及到部分全国性矿种组志书和省级矿产地质志研编成果,涵盖铀、锰、铜、铅锌、高纯石英原料矿、金、银、锂、化工等重要矿产篇以及新疆、青海、云南、贵州、广西、内蒙古、河北、吉林等省级篇。通过对已有矿产资源禀赋特征和成矿规律进行了总结,开展了成矿预测,提出了对新一轮找矿突破战略行动的找矿部署建议。 展开更多
关键词 中国矿产地质志 重要矿种 重要省份 找矿建议
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社交网络节点重要性识别研究进展
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作者 郭强 欧阳 +1 位作者 江明珠 刘建国 《电子科技大学学报》 北大核心 2025年第1期125-151,共27页
准确识别社交网络中的节点重要性对于促进或抑制信息传播、遏制疾病传播具有重要意义,同时在精准营销和社会治理等领域也具有重要理论意义和应用价值。该文从4个角度对节点影响力识别算法进行总结和梳理,具体包括:基于微观局部结构、中... 准确识别社交网络中的节点重要性对于促进或抑制信息传播、遏制疾病传播具有重要意义,同时在精准营销和社会治理等领域也具有重要理论意义和应用价值。该文从4个角度对节点影响力识别算法进行总结和梳理,具体包括:基于微观局部结构、中观的社团结构、宏观全局结构及基于机器学习的算法。详细介绍了其中的代表性算法,并从不同层面分析了不同算法的优缺点。此外还总结了常用的传播动力学模型和评价指标。最后提炼了仍需解决的问题和未来可能的研究方向。 展开更多
关键词 社交网络 节点重要性 社团结构 机器学习
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中国中间品进口供应链韧性:演进趋势、影响因素及发展对策
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作者 项松林 苏立平 《财经问题研究》 北大核心 2025年第2期80-91,共12页
在特朗普2.0时代,提升中间品进口供应链韧性对于保障中国经济安全、促进国内国际双循环具有重要的现实意义。本文区分了全球供应集中度和进口来源集中度,构建了一个可用于分析中间品进口供应链韧性的基本框架,利用CEPII BACI数据库的基... 在特朗普2.0时代,提升中间品进口供应链韧性对于保障中国经济安全、促进国内国际双循环具有重要的现实意义。本文区分了全球供应集中度和进口来源集中度,构建了一个可用于分析中间品进口供应链韧性的基本框架,利用CEPII BACI数据库的基础数据实际测算了1995—2022年中国中间品进口供应链韧性,并进一步分析了中国中间品进口供应链韧性的影响因素。研究结论如下:从演进趋势来看,1995—2022年,中国中间品进口供应链韧性逐渐提升,总体处于安全范畴,但极易受外部冲击影响。从影响因素来看,中国进口供应链韧性的主要影响因素为进口来源集中度。近年来,该因素对中国中间品供应链韧性的提升作用有所降低。“一带一路”倡议为稳定中国中间品进口供应链韧性作出积极贡献。西方发达国家极限施压的负面影响不容小觑。因此,应采取差异化政策,提升中间品进口供应链韧性;深挖潜力,努力从内部寻找替中间品;争取最大可能地与西方发达国家开展产业合作;加大国际合作力度,持续拓展进口中间品的全球来源;强化新质生产力的赋能作用,提升中间品供应链韧性。本文的研究有助于客观评估中国中间品进口供应链韧性,并为提升产业链供应链韧性提供决策参考。 展开更多
关键词 中间品进口 供应链韧性 进口来源集中度 全球供应集中度
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