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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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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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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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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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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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Variations in quantifying patient reported outcome measures to estimate treatment effect
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作者 Sathish Muthu Srujun Vadranapu 《World Journal of Methodology》 2025年第2期44-53,共10页
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ... In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice. 展开更多
关键词 Patient-reported outcome measures Treatment effect Minimal clinical important difference Patient-accepted symptom state Minimum detectable change ORTHOPEDICS
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Shareholder internationality and importing activities of emerging market firms
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作者 Pei Wang William Gonzalo Vega Salas 《Frontiers of Business Research in China》 2020年第3期383-402,共20页
In light of the increasing efforts made by emerging market firms to engage in international business through importing activities,identifying the characteristics that motivate importing busi ness and con tribute to it... In light of the increasing efforts made by emerging market firms to engage in international business through importing activities,identifying the characteristics that motivate importing busi ness and con tribute to its success is practically and theoretically meaningful.Drawing upon a knowledge-based view(KBV),we examine how the shareholder internationality affects a firm's importing activities.We hypothesize that the shareholder internationality can facilitate a firm's import initiati on and con tribute to the diversity of importing countries of origin.Moreover,the divergence of shareholders'nationality backgrounds may hinder import initiation,but motivate importing from dispersed countries of origin during the import development process.A longitudinal analysis of Colombian firms supports our hypotheses. 展开更多
关键词 Shareholder internationality importing Knowledge-based view(KBV) Emerging markets Colombia International business
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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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Foreign Trade Hits New High
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《ChinAfrica》 2025年第2期52-53,共2页
China’s foreign trade hit a record high in total value in 2024 as the world’s second-largest economy further consolidated its top position globally in goods trade.The nation’s total goods imports and exports in yua... China’s foreign trade hit a record high in total value in 2024 as the world’s second-largest economy further consolidated its top position globally in goods trade.The nation’s total goods imports and exports in yuan terms reached about$6.1 trillion last year,up 5 percent year on year,according to data released on 13 January by the General Administration of Customs(GAC). 展开更多
关键词 IMPORTS TRADE globally
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ANALYSIS OF TRUMP’S TARIFF HIKE POLICY
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作者 Cheng Rui Yuan Mulinshan Luo Weijie 《China Report ASEAN》 2025年第2期79-79,共1页
On February 1,U.S.President Donald Trump signed an executive order imposing a 10 percent tariff on imports from China.The move aligns with his“America First”trade policy,aiming to reduce the U.S.trade deficit,bring ... On February 1,U.S.President Donald Trump signed an executive order imposing a 10 percent tariff on imports from China.The move aligns with his“America First”trade policy,aiming to reduce the U.S.trade deficit,bring manufacturing back to the U.S.,and deliver on promises he made during his presidential campaign. 展开更多
关键词 China. IMPORTS TARIFF
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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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Node ranking based on graph curvature and PageRank
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作者 Hongbo Qu Yu-Rong Song +2 位作者 Ruqi Li Min Li Guo-Ping Jiang 《Chinese Physics B》 2025年第2期496-507,共12页
Identifying key nodes in complex networks is crucial for understanding and controlling their dynamics. Traditional centrality measures often fall short in capturing the multifaceted roles of nodes within these network... Identifying key nodes in complex networks is crucial for understanding and controlling their dynamics. Traditional centrality measures often fall short in capturing the multifaceted roles of nodes within these networks. The Page Rank algorithm, widely recognized for ranking web pages, offers a more nuanced approach by considering the importance of connected nodes. However, existing methods generally overlook the geometric properties of networks, which can provide additional insights into their structure and functionality. In this paper, we propose a novel method named Curv-Page Rank(C-PR), which integrates network curvature and Page Rank to identify influential nodes in complex networks. By leveraging the geometric insights provided by curvature alongside structural properties, C-PR offers a more comprehensive measure of a node's influence. Our approach is particularly effective in networks with community structures, where it excels at pinpointing bridge nodes critical for maintaining connectivity and facilitating information flow. We validate the effectiveness of C-PR through extensive experiments. The results demonstrate that C-PR outperforms traditional centrality-based and Page Rank methods in identifying critical nodes. Our findings offer fresh insights into the structural importance of nodes across diverse network configurations, highlighting the potential of incorporating geometric properties into network analysis. 展开更多
关键词 important nodes graph curvature complex networks network geometry
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Beyond the tumor region:Peritumoral radiomics enhances prognostic accuracy in locally advanced rectal cancer
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作者 Zhi-Ying Liang Mao-Li Yu +11 位作者 Hui Yang Hao-Jiang Li Hui Xie Chun-Yan Cui Wei-Jing Zhang Chao Luo Pei-Qiang Cai Xiao-Feng Lin Kun-Feng Liu Lang Xiong Li-Zhi Liu Bi-Yun Chen 《World Journal of Gastroenterology》 2025年第8期49-65,共17页
BACKGROUND The peritumoral region possesses attributes that promote cancer growth and progression.However,the potential prognostic biomarkers in this region remain relatively underexplored in radiomics.AIM To investig... BACKGROUND The peritumoral region possesses attributes that promote cancer growth and progression.However,the potential prognostic biomarkers in this region remain relatively underexplored in radiomics.AIM To investigate the prognostic value and importance of peritumoral radiomics in locally advanced rectal cancer(LARC).METHODS This retrospective study included 409 patients with biopsy-confirmed LARC treated with neoadjuvant chemoradiotherapy and surgically.Patients were divided into training(n=273)and validation(n=136)sets.Based on intratumoral and peritumoral radiomic features extracted from pretreatment axial high-resolution small-field-of-view T2-weighted images,multivariate Cox models for progression-free survival(PFS)prediction were developed with or without clinicoradiological features and evaluated with Harrell’s concordance index(C-index),calibration curve,and decision curve analyses.Risk stratification,Kaplan-Meier analysis,and permutation feature importance analysis were performed.RESULTS The comprehensive integrated clinical-radiological-omics model(ModelICRO)integrating seven peritumoral,three intratumoral,and four clinicoradiological features achieved the highest C-indices(0.836 and 0.801 in the training and validation sets,respectively).This model showed robust calibration and better clinical net benefits,effectively distinguished high-risk from low-risk patients(PFS:97.2%vs 67.6%and 95.4%vs 64.8%in the training and validation sets,respectively;both P<0.001).Three most influential predictors in the comprehensive ModelICRO were,in order,a peritumoral,an intratumoral,and a clinicoradiological feature.Notably,the peritumoral model outperformed the intratumoral model(C-index:0.754 vs 0.670;P=0.015);peritumoral features significantly enhanced the performance of models based on clinicoradiological or intratumoral features or their combinations.CONCLUSION Peritumoral radiomics holds greater prognostic value than intratumoral radiomics for predicting PFS in LARC.The comprehensive model may serve as a reliable tool for better stratification and management postoperatively. 展开更多
关键词 Rectal cancer Peritumoral radiomics Intratumoral radiomics Prognosis analysis Variable importance analysis Tumor microenvironment
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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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Top Players in Importing and Exporting Pesticides in China in 2008
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《China Chemical Reporter》 2009年第8期47-47,共6页
关键词 Top Players in importing and Exporting Pesticides in China in 2008
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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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Importing cars is becoming a higher-risk business
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《中国汽车(英文版)》 2002年第8期10-11,共2页
Following China’s WTO entry, most importers and consumers were optimistic about the imported car market at the beginning of this year. As of July, the market indicated, however, despite the import tariffs having been... Following China’s WTO entry, most importers and consumers were optimistic about the imported car market at the beginning of this year. As of July, the market indicated, however, despite the import tariffs having been reduced in accordance with the WTO commitment, the prices of imported cars rebounded rapidly after a short period 展开更多
关键词 IMPORTED BECOMING prices COMMITMENT CUSTOMS BEGINNING despite Tianjin FIGURES accordance
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中国古代槟榔文化的接受与传播
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作者 冯青 《农业考古》 北大核心 2024年第4期195-201,共7页
作为舶来品的槟榔,在饮食、医药、赋税等方面扮演过重要的角色,具有丰厚的历史文化。梳理文献发现,两汉三国时期,槟榔视作“奇草异木”记载在各种《异物志》中,开始被接受;南北朝时期,槟榔是贵族士宦的“奢侈品”,唐代受佛教平等思想影... 作为舶来品的槟榔,在饮食、医药、赋税等方面扮演过重要的角色,具有丰厚的历史文化。梳理文献发现,两汉三国时期,槟榔视作“奇草异木”记载在各种《异物志》中,开始被接受;南北朝时期,槟榔是贵族士宦的“奢侈品”,唐代受佛教平等思想影响日渐向大众传播,宋代逐渐成为百姓家的“寻常物”。槟榔之所以能被接受与传播,并在海南用于婚俗,是因其本身的物质文化之外,还与其因贵异而用于重要的人际礼仪、文人墨客极力推崇渲染和赋予了槟榔君子品格等精神文化有着莫大的关系。 展开更多
关键词 betel nut culture imported product ACCEPTANCE DISSEMINATION
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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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Data-driven casting defect prediction model for sand casting based on random forest classification algorithm 被引量:1
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作者 Bang Guan Dong-hong Wang +3 位作者 Da Shu Shou-qin Zhu Xiao-yuan Ji Bao-de Sun 《China Foundry》 SCIE EI CAS CSCD 2024年第2期137-146,共10页
The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was p... The complex sand-casting process combined with the interactions between process parameters makes it difficult to control the casting quality,resulting in a high scrap rate.A strategy based on a data-driven model was proposed to reduce casting defects and improve production efficiency,which includes the random forest(RF)classification model,the feature importance analysis,and the process parameters optimization with Monte Carlo simulation.The collected data includes four types of defects and corresponding process parameters were used to construct the RF model.Classification results show a recall rate above 90% for all categories.The Gini Index was used to assess the importance of the process parameters in the formation of various defects in the RF model.Finally,the classification model was applied to different production conditions for quality prediction.In the case of process parameters optimization for gas porosity defects,this model serves as an experimental process in the Monte Carlo method to estimate a better temperature distribution.The prediction model,when applied to the factory,greatly improved the efficiency of defect detection.Results show that the scrap rate decreased from 10.16% to 6.68%. 展开更多
关键词 sand casting process data-driven method classification model quality prediction feature importance
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