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Structural Reliability Analysis Based on Differential Evolution Algorithm and Hypersphere Integration
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作者 CHEN Zhenzhong HAN Zhuo +4 位作者 WANG Peiyu PAN Qianghua LI Xiaoke GAN Xuehui CHEN Ge 《Journal of Donghua University(English Edition)》 2026年第1期118-130,共13页
In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order relia... In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order reliability methods exhibit limited accuracy in highly nonlinear scenarios.To overcome these challenges,a novel reliability analysis strategy based on a multimodal differential evolution algorithm and a hypersphere integration method is proposed.Initially,the penalty function method is employed to reformulate the MPP search problem as a conditionally constrained optimization task.Subsequently,a differential evolution algorithm incorporating a population delineation strategy is utilized to identify all MPPs.Finally,a paraboloid equation is constructed based on the curvature of the limit-state function at the MPPs,and the failure probability of the structure is calculated by using the hypersphere integration method.The localization effectiveness of the MPPs is compared through multiple numerical cases and two engineering examples,with accuracy comparisons of failure probabilities against the first-order reliability method(FORM)and the secondorder reliability method(SORM).The results indicate that the method effectively identifies existing MPPs and achieves higher solution precision. 展开更多
关键词 reliability analysis design point positioning differential evolution algorithm hypersphere integration
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Evolution and insights of China’s environmental governance policies:An LDA-based policy text analysis
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作者 HUA Yu-chen YANG Jia-meng +2 位作者 WEI Ren-jie CHENG Xiu LIU Zhi-yong 《Ecological Economy》 2026年第1期2-30,共29页
China’s environmental governance strategy provides a distinctive pathway for integrating sustainable development into national policy.Understanding its policy trajectory is essential for assessing China’s contributi... China’s environmental governance strategy provides a distinctive pathway for integrating sustainable development into national policy.Understanding its policy trajectory is essential for assessing China’s contribution to global sustainable development and the United Nations Sustainable Development Goals(SDGs).This study constructs a comprehensive database of 425 national environmental governance policy documents issued between 1978 and 2022 and applies Latent Dirichlet Allocation(LDA)modeling to examine the evolution of policy themes and discourse.The results show that China’s environmental governance has undergone four stages-initial exploration,detailed development,transformative leap,and diverse prosperity-reflecting a progressive shift toward more integrated and coordinated governance.Policy priorities have evolved from a primary focus on pollution control and energy transition to an emphasis on institutional construction and organizational reform,thereby strengthening alignment with the SDGs.This transformation is characterized by recurring developmental themes and increasingly preventive,forward-looking,and system-oriented governance approaches.Moreover,the co-evolution of policy concepts and implementation has driven a transition from localized,end-of-pipe responses to comprehensive governance frameworks,alongside a shift from normative guidance towards effectiveness-oriented policy design.By employing a data-driven text analysis approach,this study offers a systematic framework for tracing long-term policy evolution and assessing its implications for sustainable development. 展开更多
关键词 environmental governance policy text analysis LDA topic modeling topic evolution sustainable development policy policy transformation
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Interdisciplinary integration and development trends of intelligent diagnosis in traditional Chinese medicine:a topic evolution analysis
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作者 Chenggong Xie Keying Huang +2 位作者 Zhengquan Du Xinyi Huang Bin Wang 《Digital Chinese Medicine》 2026年第1期43-56,共14页
Objective To systematically characterize the developmental trajectory and interdisciplinary integration of intelligent diagnosis in traditional Chinese medicine(TCM)through quantitative topic evolution analysis,we add... Objective To systematically characterize the developmental trajectory and interdisciplinary integration of intelligent diagnosis in traditional Chinese medicine(TCM)through quantitative topic evolution analysis,we addressed the fragmentation of existing research and clarified the long-term research structure and evolutionary patterns of the field.Methods A topic evolution analysis was performed on Chinese-language literature pertaining to intelligent diagnosis in TCM.Publications were retrieved from the China National Knowledge Infrastructure(CNKI),Wanfang Data,and China Science and Technology Journal Database(VIP),covering the period from database inception to July 3,2025.A hybrid segmentation approach,based on cumulative publication growth trends and inflection point detection,was applied to divide the research timeline into distinct stages.Subsequently,the latent Dirichlet allocation(LDA)model was used to extract research topics,followed by alignment and evolutionary analysis of topics across different stages.Results A total of 3919 publications published between 2003 and 2025 were included,and the research trajectory was divided into five stages based on data-driven breakpoint detection.The field exhibited a clear evolutionary shift from early rule-based systems and tonguepulse image and signal analysis(2006–2010),to machine-learning-based syndrome and prescription modeling(2011–2015),followed by deep-learning-driven pattern recognition and formula association(2016–2020).Since 2021,research has increasingly emphasized knowledge-graph construction,multimodal integration,and intelligent clinical decision-support systems,with recent studies(2024–2025)showing the emergence of large language models and agent-based diagnostic frameworks.Topic evolution analysis further revealed sustained cross-stage continuity in syndrome modeling and prescription association analysis,alongside the progressive consolidation of integrated intelligent diagnostic platforms.Conclusion By identifying key technological transitions and persistent core research themes,our findings offer a structured reference framework for the design of intelligent diagnostic systems,the construction of knowledge-driven clinical decision-support tools,and the alignment of AI models with TCM diagnostic logic.Importantly,the stage-based evolutionary insights derived from this analysis can inform future methodological choices,improve model interpretability and clinical applicability,and support the translation of intelligent TCM diagnosis from experimental research to real-world clinical practice. 展开更多
关键词 Traditional Chinese medicine diagnosis Artificial intelligence Interdisciplinary integration Research stage identification Topic evolution analysis Latent Dirichlet allocation model
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Microscopic analysis of mechanical anisotropy and damage evolution of 3D printed rock-like samples under uniaxial compressive tests 被引量:1
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作者 Yulong Shao Jingwei Yang +3 位作者 Jineon Kim Jae-Joon Song Juhyuk Moon Jianyong Han 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期688-704,共17页
Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects ... Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects such as cracks and pores.In this study,3DP gypsum samples with different printing directions were subjected to a series of uniaxial compression tests with in situ micro-computed tomography(micro-CT)scanning to quantitatively investigate their mechanical anisotropic properties and damage evolution characteristics.Based on the two-dimensional(2D)CT images obtained at different scanning steps,a novel void ratio variable was derived using the mean value and variance of CT intensity.Additionally,a constitutive model was formulated incorporating the proposed damage variable,utilizing the void ratio variable.The crack evolution and crack morphology of 3DP gypsum samples were obtained and analyzed using the 3D models reconstructed from the CT images.The results indicate that 3DP gypsum samples exhibit mechanical anisotropic characteristics similar to those found in naturally sedimentary rocks.The mechanical anisotropy is attributed to the bedding planes formed between adjacent layers and pillar-like structures along the printing direction formed by CaSO_(4)·2H_(2)O crystals of needle-like morphology.The mean gray intensity of the voids has a positive linear relationship with the threshold value,while the CT variance and void ratio have concave and convex relationships,respectively.The constitutive model can effectively match the stress–strain curves obtained from uniaxial compression experiments.This study provides comprehensive explanations of the failure modes and anisotropic mechanisms of 3DP gypsum samples,which is important for characterizing and understanding the failure mechanism and microstructural evolution of 3DP rocks when modeling natural rock behavior. 展开更多
关键词 Quantitative analysis Three-dimensional printing(3DP) Gypsum samples In situ micro-computed tomography(micro-CT)scanning Mechanical anisotropy Bedding planes Damage evolution
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Topic Mining and Evolution Analysis of Domestic Smart Library Research Based on the BERTopic Model
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作者 Meile Li Yinuo Jiang 《Journal on Artificial Intelligence》 2025年第1期509-516,共8页
This paper conducts topic mining and analysis of research literature in the domestic smart library field based on the BERTopic model,aiming to reveal its topic development context and evolution trends.Journal literatu... This paper conducts topic mining and analysis of research literature in the domestic smart library field based on the BERTopic model,aiming to reveal its topic development context and evolution trends.Journal literature in the smart library field collected by CNKI(China National Knowledge Infrastructure)from 2015 to 2024 was analyzed using the BERTopic model and dynamic topic modeling for topic mining and evolution trend analysis.The study found that the domestic smart library field involves multiple core topics,identifying a diversified topic structure centered around“data”,“user”,“5g”,etc.The research results provide data support and practical reference for libraries to accurately identify key points of technology integration during smart transformation and to optimize smart service models. 展开更多
关键词 Domestic smart library BERTopic topic mining evolution analysis
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Genome-wide Analysis of Glucose-6-phosphate Dehydrogenase(G6PDH) and Its Evolution in Eucalyptus grandsis 被引量:3
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作者 林元震 张志毅 +1 位作者 林善枝 刘纯鑫 《Agricultural Science & Technology》 CAS 2011年第9期1276-1278,共3页
[Objective] The aim of this study was to perform genome-wide analysis of glucose-6-phosphate dehydrogenase(G6PDH) and reveal its evolution in Eucalyptus grandsis.[Method] The gene character,protein sequence and phyl... [Objective] The aim of this study was to perform genome-wide analysis of glucose-6-phosphate dehydrogenase(G6PDH) and reveal its evolution in Eucalyptus grandsis.[Method] The gene character,protein sequence and phylogenetic tree of G6PDH gene were analyzed by BLAST and other bioinformatics software within Eucalyptus grandsis whole genome database.[Result] Six G6PDH genes,including one cytomic type and five plastids,were detected in the E.grandsis genome.All the G6PDHs have conserved motifs of motif 1,motif 2,motif 3,motif 7,motif 9 and motif 11.Furthermore,promoter sequences of all E.grandsis G6PDH contain TATA box,enhancer,light-responsive,hormone-responsive and stress-responsive regulatory elements.[Conclusion] This study provided reference for the further revealing molecular function of E.grandsis G6PDH gene family 展开更多
关键词 Eucalyptus grandsis Glucose-6-phosphate dehydrogenase evolution analysis Conserved motif
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Analysis of Pedigree and Trait Evolution of Peanut Varieties Registered in Fujian Province
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作者 黄金堂 陈海玲 郑国栋 《Agricultural Science & Technology》 CAS 2013年第4期606-611,619,共7页
In order to provide reference for the breeding of new peanut varieties and introduction of peanut cultivars in Fujian Province, the pedigree and trait evolution of 33 peanut varieties registered (certified, identifie... In order to provide reference for the breeding of new peanut varieties and introduction of peanut cultivars in Fujian Province, the pedigree and trait evolution of 33 peanut varieties registered (certified, identified) during 1949-2011 in Fujian Province were analyzed. Results showed that, 45 parents were used as parents for peanut breeding, and 22 parents were originated from Fujian Province, 24 parents were registered varieties; Shitouqi, Yueyou 92, Shanyou 523, Quanhua No.10 and Quanhua 327 were milestone parents of peanut varieties in Fujian Province, and the phylogenetic relationship of varieties mainly came from Guangdong. Systematic se- lection was the main breeding method during 1951-1980 in Fujian Province, while crossbreeding became the main method of peanut breeding since 1991. With the variety update of peanuts, the yield levels were constantly increasing. The gradual increase of 100-pod weight and 100-kernel weight played an important role in the improvement of peanut yield. Fat content increased slightly with time, while protein content changed in contrast. Plant height was gradually decreased, and anti-lodging and fertilizer-tolerance capacity was improved, which were suitable for close planting. The total number of branches was decreased slightly, while the number of bearing branches barely changed. 展开更多
关键词 Fujian PEANUT PEDIGREE Trait evolution analysis
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Coupled TM-damage modeling and global sensitivity analysis of thermal spalling in heterogeneous rocks
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作者 Liyuan Liu Mingshan Shi +4 位作者 Derek Elsworth Tao Wang Hongguang Ji Le Zhang Yaohui Li 《International Journal of Mining Science and Technology》 2026年第3期535-552,共18页
Thermal spalling in heterogeneous rocks under rapid heating poses critical risks to deep mining and geothermal operations.In this study,we develop a coupled thermal-mechanical-damage(TM D)model that explicitly incorpo... Thermal spalling in heterogeneous rocks under rapid heating poses critical risks to deep mining and geothermal operations.In this study,we develop a coupled thermal-mechanical-damage(TM D)model that explicitly incorporates Weibull distributed heterogeneity to a single fracture in rock,and validate it against ceramic quenching and granite acoustic emission experiments.Distance based generalized sensitivity analysis(DGSA)is applied to quantify the influence and interactions of key parameters,revealing the dominant controls on spalling onset,severity,and damage morphology.The results demonstrate that thermal stress dominates crack initiation and propagation,that lateral constraints can significantly delay and suppress spalling,and that material heterogeneity markedly influences peak stress and damage modes within a certain range of thermal expansion coefficient and has multiple effects on thermal spalling.This study provides a theoretical basis for quantitative assessment and parameter optimization of thermal spalling processes in rock masses. 展开更多
关键词 Rock heterogeneity Thermal spalling Microstructure evolution Sensitivity analysis Parameter interaction effect
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Assessing neotectonic deformation and terrain evolution through geospatial morphometric techniques across the MBT zone,NW Himalaya
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作者 CHANGMAI Jayshree PATIDAR Atul Kumar KOTHYARI Girish Ch 《Journal of Mountain Science》 2026年第3期1079-1104,共26页
The transitional zone between the Sub-Himalaya and the Lesser Himalaya is delineated by the Main Boundary Thrust(MBT)to the north and the Himalayan Frontal Thrust(HFT)to the south.The MBT acts as a major topographic b... The transitional zone between the Sub-Himalaya and the Lesser Himalaya is delineated by the Main Boundary Thrust(MBT)to the north and the Himalayan Frontal Thrust(HFT)to the south.The MBT acts as a major topographic barrier that exerts significant control over longitudinal river valleys and sediment dispersal patterns.This region exhibits pronounced fluvial responses shaped by the interplay of tectonic activity and climatic processes.The present study addresses the need for detailed micro-scale morphometric analysis in this zone to better understand ongoing landscape deformation and neotectonic signatures.A multidisciplinary approach integrating geospatial morphometric techniques with field-based evidence has been employed to investigate terrain evolution.Quantitative morphometric assessments were conducted for 16 sub-basins within an active segment of the MBT,bounded by the Jakhan River to the east and the Giri River to the west.Dimensional changes driven by tectonic uplift and accelerated erosion/incision were evaluated using the hypsometric integral(HI),with most values falling below 0.50,indicating that the drainage basins are in an equilibrium stage.Basin shape(Bs)values range from 0.88 to 6.79,supporting the occurrence of accelerated erosional processes.The stream length gradient index(SL)exhibits values between 86 and 816,suggesting rapid uplift and incision.Similarly,computed values of the Chi(χ)coefficient(479-3706)and the steepness index(Ksn;63-214)reflect differential erosion and strong tectonic control on drainage network evolution.The spatial distribution of tectonic deformation was statistically evaluated using a correlation matrix based on the Relative Index of Active Tectonics(RIAT).The results reveal that approximately 50.33%and 16.25%of the study area fall into high and moderate activity zones,respectively,which is corroborated by historical earthquake records and geomorphic evidence.Neotectonic signatures are preserved in the landscape as river terraces,displaced or tilted strata,V-shaped valleys,river offsets,knickpoints,hanging valleys,and channel migration along the strike of the MBT.These findings underscore the significant role of neotectonics in landform evolution and offer valuable insights for geohazard assessment and mitigation strategies in the rapidly developing foothill regions of the Himalaya. 展开更多
关键词 NEOTECTONICS Morphometric analysis Main Boundary Thrust Fluvial response Relative Index of Active Tectonics(RIAT) Landscape evolution HIMALAYA
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Visual analysis of the evolution and focus in landslide research field 被引量:5
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作者 YANG Jing CHENG Chang-xiu +2 位作者 SONG Chang-qing SHEN Shi NING Li-xin 《Journal of Mountain Science》 SCIE CSCD 2019年第5期991-1004,共14页
This paper analysed the evolution of landslide research and research foci in different countries. The data comprise 3105 landslide SCI articles published between January 1977 and June 2015 from the Web of Science. The... This paper analysed the evolution of landslide research and research foci in different countries. The data comprise 3105 landslide SCI articles published between January 1977 and June 2015 from the Web of Science. The data are extracted under interaction constraints of the journal title, category, and keywords. The complex network method is used for the analysis. First, from the perspective of topics and methods, the evolution is systematically assessed by generating a co-citation network of the articles and a semantic cluster analysis. Second, from the perspective of topics and landsliderelated disasters, the focus in different countries is discussed by generating co-occurrence networks. These networks are the co-occurrence of the countries and keywords, and the co-occurrence of countries and landslide-related disaster phrases. The main conclusions are as follows:(1) landslide susceptibility analysis and methods of machine learning are popular research topics and methods, respectively. The topics change through time, and the article output is influenced by increasing landslide-related disasters, increasing economic losses and casualties, a desire for a more complete and accurate landslide inventory, and the use of effective methods, such as geographical information Science(GIS) and machine learning.(2) The research focus in each country is related with the country-specific disasters or economic costs caused by landslides to some degree. In addition to Italy and the USA, China is the country most commonly affected by landslides, and it should develop its own landslide database and complete in-depth studies of disaster mitigation. 展开更多
关键词 LANDSLIDES COMPLEX network CLUSTER analysis evolution Research FOCUS
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A novel approach of testability modeling and analysis for PHM systems based on failure evolution mechanism 被引量:16
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作者 Tan Xiaodong Qiu Jing +3 位作者 Liu Guanjun Lv Kehong Yang Shuming Wang Chao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第3期766-776,共11页
Prognostics and health management (PHM) significantly improves system availability and reliability, and reduces the cost of system operations. Design for testability (DFT) developed concurrently with system design... Prognostics and health management (PHM) significantly improves system availability and reliability, and reduces the cost of system operations. Design for testability (DFT) developed concurrently with system design is an important way to improve PHM capability. Testability modeling and analysis are the foundation of DFT. This paper proposes a novel approach of testability modeling and analysis based on failure evolution mechanisms. At the component level, the fault progression-related information of each unit under test (UUT) in a system is obtained by means of failure modes, evolution mechanisms, effects and criticality analysis (FMEMECA), and then the failure-symptom dependency can be generated. At the system level, the dynamic attributes of UUTs are assigned by using the bond graph methodology, and then the symptom-test dependency can be obtained by means of the functional flow method. Based on the failure-symptom and symptom-test dependencies, testability analysis for PHM systems can be realized. A shunt motor is used to verify the application of the approach proposed in this paper. Experimental results show that this approach is able to be applied to testability modeling and analysis for PHM systems very well, and the analysis results can provide a guide for engineers to design for testability in order to improve PHM performance. 展开更多
关键词 Design for testability Failure evolution mechanism Failure-symptom dependency Prognostics and health management Symptom-test dependency Testability modeling and analysis Unit under test
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Analyzing space-time evolution of rural transition in a rapidly urbanizing region:A case study of Suzhou,China 被引量:4
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作者 ZHANG Ruoyan LI Hongbo YUAN Yuan 《Journal of Geographical Sciences》 SCIE CSCD 2022年第7期1343-1356,共14页
Influenced by globalization,rural transition in developed Western countries has experienced processes of productivism,post-productivism,and multifunctional development.By contrast,rural transition in most developing c... Influenced by globalization,rural transition in developed Western countries has experienced processes of productivism,post-productivism,and multifunctional development.By contrast,rural transition in most developing countries has been accompanied by rapid urbanization,which has become a core topic in geography research.As the world’s largest developing country,China has undergone profound development since the reform and opening-up.Moreover,rural spaces in some eastern coastal areas have entered the stage of reconstruction after decades of industrialization and urbanization.This paper takes Suzhou as the case area and measures the process of rural transition from 1990 to 2015 by constructing an index system.It then analyzes the characteristics of space-time evolution using exploratory spatial data analysis(ESDA)methods to reveal the influence of economic and social development on rural transition.The results show that rural transition,which generally entails the weakening of rurality and enhancing of urbanity on a macro scale,tends to be heterogeneous across different regions on a micro scale.This paper argues that multifunctionality will be the main future trend of rural transition in rapidly urbanizing areas.The experience in Suzhou could provide an example for establishing policies on sustainable development in rural spaces and achieving urban-rural co-governance. 展开更多
关键词 rural transition multifunctionality rural revitalization SUZHOU space-time evolution exploratory spatial data analysis(ESDA)
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Functional Spectral Analysis of Paleoclimatic Evolution in Lanzhou Area over the Last 15 ka 被引量:2
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作者 杨桂芳 殷鸿福 +1 位作者 李长安 陈中原 《Chinese Journal Of Geochemistry》 EI CAS 2003年第4期377-380,共4页
In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 conte... In this paper, we make use of the functional spectral analysis to infer the periodicity of paleoclimate in the Hongzuisi section since about 15 ka. Through combined analysis of organic carbon isotope and CaCO\-3 content, the law of paleoclimatic evolution of the Hongzuisi section is obtained. There were climatic changes from 10 ka to about 0.1 ka over the last 15 ka. Among these cycles, the cycle of several ka is most remarkable. The result indicates that functional spectral analysis is helpful for paleoclimatic study, which can provide useful information about paleoclimatic reconstruction and future forecast. 展开更多
关键词 PALEOCLIMATIC evolution FUNCTIONAL spectral analysis organic carbon ISOTOPE CAC03 content
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Spatiotemporal evolution and driving factors of global production networks:An analysis based on the input-output technique 被引量:6
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作者 ZHENG Zhi CHEN Wei +1 位作者 LIANG Yi ZHANG Yajing 《Journal of Geographical Sciences》 SCIE CSCD 2021年第5期641-663,共23页
Global production networks have become the most important organizational platforms for coordinating international production activities,and their evolution patterns profoundly affect value distribution across the worl... Global production networks have become the most important organizational platforms for coordinating international production activities,and their evolution patterns profoundly affect value distribution across the world.In this study,we shall firstly carry out an in-depth quantitative research to analyze the patterns and evolution of global production networks,using a long time-sequenced multi-region input-output table and the network analysis approach.Then based on the method of value-added decomposition,we will develop an index system to measure the degree of participation of regions in global production networks.Finally,we will try to identify the factors affecting the degree of participation of countries in global production networks by constructing a regression model.The results show that from 1995 to 2015,the evolution of global production networks measured by input-output linkages experienced four stages:expansion,contraction,re-expansion,and re-contraction.In addition,the core communities of global production networks evolved from two major production communities(Europe and the Americas)to three pillars(Europe,Americas,and Asia)while more segmented communities are mainly affected by geographical proximity.The latter consists of European,North American,South American,African and Asian communities.The evolution of the global production network pattern primarily manifests as a process of cooperation strengthening or weakening among communities,based on changes in the external environment and the need for individual development strategies.Meanwhile,the United States,Germany,and the United Kingdom have consistently ranked among the top entities in global production networks,whereas China,Russia,and Southeast Asia have the fastest rises in ranking.In addition,government efficiency,resources endowment,infrastructure conditions and technology levels play important roles in the participation in global production networks. 展开更多
关键词 input-output table network analysis evolution pattern value-added decomposition participation degree indicator system
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A PRELIMINARY STUDY ON THE 3DVAR ASSIMILATION OF THE AMSU-A DATA IN SPACE-TIME MULTISCALE ANALYSIS SYSTEM 被引量:4
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作者 LIU Rui-xia XIE Yuan-fu LIU Jie 《Journal of Tropical Meteorology》 SCIE 2017年第3期314-322,共9页
Assimilating satellite radiances into Numerical Weather Prediction(NWP) models has become an important approach to increase the accuracy of numerical weather forecasting. In this study, the assimilation technique sche... Assimilating satellite radiances into Numerical Weather Prediction(NWP) models has become an important approach to increase the accuracy of numerical weather forecasting. In this study, the assimilation technique scheme was employed in NOAA's STMAS(Space-Time Multiscale Analysis System) to assimilate AMSU-A radiances data.Channel selection sensitivity experiments were conducted on assimilated satellite data in the first place. Then, real case analysis of AMSU-A data assimilation was performed. The analysis results showed that, following assimilating of AMSU-A channels 5-11 in STMAS, the objective function quickly converged, and the channel vertical response was consistent with the AMSU-A weighting function distribution, which suggests that the channels can be used in the assimilation of satellite data in STMAS. With the case of the Typhoon Morakot in Taiwan Island in August 2009 as an example, experiments on assimilated and unassimilated AMSU-A radiances data were designed to analyze the impact of the assimilation of satellite data on STMAS. The results demonstrated that assimilation of AMSU-A data provided more accurate prediction of the precipitation region and intensity, and especially, it improved the 0-6h precipitation forecast significantly. 展开更多
关键词 MULTIGRID 3DVAR space-time multiscale analysis system numerical experiments
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Evolution Analysis About Soybean MIR166 Family 被引量:2
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作者 Wang Zhi-hao Jin Hui-hui +1 位作者 Chen Qing-shan Zhu Rong-sheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2015年第1期22-29,共8页
MicroRNA(miRNA) is a class of important regulating non-coding small molecular RNA. The gma-MIR166 gene family consists of 21 members and their expression patterns diversify widely. It is important to analyze the evo... MicroRNA(miRNA) is a class of important regulating non-coding small molecular RNA. The gma-MIR166 gene family consists of 21 members and their expression patterns diversify widely. It is important to analyze the evolution of gma-MIR166 gene family in order to understand the evolutionary mechanisms of miRNAs in soybean. In this study, we implemented soybean wide genome block analysis, the molecular phylogeny of gma-MIR166 and block analysis of gma-MIR166 family. The results showed that both chromosome big segmental duplications and tandem duplications were main reasons contributed to the expanding of gmaMIR166 gene family. These findings suggested that gma-MIR166 gene family might originate from one or two ancient miRNA genes. The results of research provided a support for evolutionary study of miRNAs in soybean and related species in Fabaceae. 展开更多
关键词 microRNA family evolution SOYBEAN block analysis
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Genotype distribution and evolutionary analysis of rotavirus associated with acute diarrhea outpatients in Hubei,China,2013–2016 被引量:3
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作者 Ting Zhang Jing Li +5 位作者 Yong-Zhong Jiang Jun-Qiang Xu Xu-Hua Guan Li-Qiang Wang Jie Chen Yi Liang 《Virologica Sinica》 SCIE CAS CSCD 2022年第4期503-512,共10页
Group A human rotaviruses(RVAs)annually cause the deaths of 215,000 infants and young children.To understand the epidemiological characteristics and genetic evolution of RVAs,we performed sentinel surveillance on RVA ... Group A human rotaviruses(RVAs)annually cause the deaths of 215,000 infants and young children.To understand the epidemiological characteristics and genetic evolution of RVAs,we performed sentinel surveillance on RVA prevalence in a rotavirus-surveillance network in Hubei,China.From 2013 to 2016,a total of 2007 fecal samples from hospital outpatients with acute gastroenteritis were collected from four cities of Hubei Province.Of the 2007 samples,153(7.62%)were identified positive for RVA by real-time RT-PCR.RVA infection in Hubei mainly occurred in autumn and winter.The highest detection rate of RVA infection was in 1–2 years old of outpatients(16.97%).No significant difference of RVA positive rate was observed between females and males.We performed a phylogenetic analysis of the G/P genotypes based on the partial VP7/VP4 gene sequences of RVAs.G9P[8]was the most predominant strain in all four years but the prevalence of G2P[4]genotype increased rapidly since 2014.We reconstructed the evolutionary time scale of RVAs in Hubei,and found that the evolutionary rates of the G9,G2,P[8],and P[4]genotypes of RVA were 1.069×10^(-3),1.029×10^(-3),1.283×10^(-3)and 1.172×10^(-3)nucleotide substitutions/site/year,respectively.Importantly,using a molecular clock model,we showed that most G9,G2,P[8],and P[4]genotype strains dated from the recent ancestor in 2005,2005,1993,and 2013,respectively.The finding of the distribution of RVAs in infants and young children in Hubei Province will contribute to the understanding of the epidemiological characteristics and genetic evolution of RVAs in China. 展开更多
关键词 Group A human rotavirus(RVA) PREVALENCE Phylogenetic analysis evolution Hubei Province
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Space-time analysis of the changing patterns of population pressure on the ecological environment in China 被引量:1
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作者 Dongqi Sun Jinliang Jiang +2 位作者 Jianbin Xu Liang Zhou Yi Hu 《Chinese Journal of Population,Resources and Environment》 2015年第4期341-348,共8页
This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrat... This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality. 展开更多
关键词 Chinese POPULATION ECO-ENVIRONMENT ECO-ENVIRONMENTAL pressure CHANGING TREND space-time analysis
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Spectra analysis and O_2 evolution for TiO_2 photocatalyst compounded with indirect transition semiconductors 被引量:2
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作者 童海霞 柴立元 张馨睿 《Journal of Central South University》 SCIE EI CAS 2012年第9期2425-2433,共9页
The photo absorbing, photo transmitting and photoluminescence performances of WiO2 photocatalysts compounded with V2O5 or WO3 were investigated by UV-Vis spectra, transmitting spectra, and PL spectra, respectively. Th... The photo absorbing, photo transmitting and photoluminescence performances of WiO2 photocatalysts compounded with V2O5 or WO3 were investigated by UV-Vis spectra, transmitting spectra, and PL spectra, respectively. The energy band structures of TiO2 photocatalysts were analyzed. The photocatalytic activities of the TiO2 photocatalysts were investigated by splitting of water for 02 evolution. The results indicate that the band gaps of WO3 and V205 are about 2.8 and 2.14 eV, respectively, and the band gap of rutile TiO2 is about 3.08 eV. Speeds of water splitting for 2%WO3-TiO2 and 8%V2O5-TiO2 photocatalysts are 420 and 110 μmol/(L.h), respectively, under UV light irradiation. V2O5 and WO3 compounded with suitable concentration can improve the photocatalytic activity of TiO2 with Fe3+ as electron acceptor. 展开更多
关键词 TiO2 photocatalyst indirect transition semiconductor spectra analysis photo splitting water 02 evolution
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ANALYSIS OF EVOLUTIONARY RELATIONSHIP BETWEEN ASTASIA LONGA AND EUGLENA GRACILIS BY USING RAPD TECHNIQUE AND CLADISTIC ANALYSIS 被引量:1
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作者 王江新 施之新 +1 位作者 甘小妮 谢树莲 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第1期40-50,共11页
Although both Astasia longa and Euglena gracilis belong to different genera, they share many morphological characters except that A. longa has no chloroplast. In the 1940’s, on the basis of the finding that in darkne... Although both Astasia longa and Euglena gracilis belong to different genera, they share many morphological characters except that A. longa has no chloroplast. In the 1940’s, on the basis of the finding that in darkness or upon addition of some chemicals, E. gracilis would fade reversibly or irreversibly, some scholars hypothesised that A. longa evolved from E. gracilis by losing chloroplast. The authors’ use of RAPD and cladistic analyses in a study on the evolutionary relationship between A .longa and E. gracilis showed that the A. longa ’s relationship with E. gracilis was closer than that with other green euglenoids. This proves the hypothesis that A. longa evolved from E. gracilis is reasonable. The results of this study suggest that saprophytic colorless euglenoids were transformed from green euglenoids by losing their choroplasts. 展开更多
关键词 A. longa Euglena gracilis cladistic analysis molecular evolution RAPD
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