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Analysis and prediction of glacier evolution trend(2020-2100)in Northern Xinjiang
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作者 Xi-yong Sun Yang Jiao +5 位作者 Qian-li Ma Jing-hui Fan Xiao-min Du Jia-feng Liu Shao-qiang Wang Wen-chen Hu 《China Geology》 CAS CSCD 2024年第4期661-671,共11页
Glaciers,as“solid reservoirs”,are precious resources in arid areas.The study of glaciers is of great significance to the sustainable development and management of agriculture and the economy in northern Xinjiang.The... Glaciers,as“solid reservoirs”,are precious resources in arid areas.The study of glaciers is of great significance to the sustainable development and management of agriculture and the economy in northern Xinjiang.The area of glacier distribution on the 1963 topographic map data,1975 MSS data,2000 ETM data,2008 CBERS-2 data,2014 and 2018 ETM+were collected as secondary data.According to the remote sensing survey,the glacier areas in Northern Xinjiang are identified during 1963-2018.Based on the evolution of glacier area in the past 55 years,and using two scenarios,the average annual decrease area of a region during the whole 1963-2018 and the period with the minimum reduction area,the glacier areas of Southern Tianshan Mountains,Western Tianshan Mountains,Eastern Tianshan Mountains,the Sawuer Mountains and Altai Mountains in Northern Xinjiang,and the whole northern Xinjiang in 2030,2040,2050,and 2100 are examined and predicted.In 2100,the glacier area in Northern Xinjiang may decrease by 43%-59%. 展开更多
关键词 Glacial evolution Glacial area Global warm Trend analysis Glacial disappear Environmental change Northern Xinjiang Altai Mountains of Central Asia
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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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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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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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Functional Spectral Analysis of Paleoclimatic Evolution in Lanzhou Area over the Last 15 ka 被引量:1
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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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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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An SAO-based approach to technology evolution analysis using patent information: Case study—graphene sensors 被引量:11
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作者 Zhengyin HU Shu FANG +3 位作者 Ling WEI Yi WEN Xian ZHANG Min WANG 《Chinese Journal of Library and Information Science》 2015年第3期62-75,共14页
Purpose: This paper introduces an approach to technology evolution analysis using patent information based on Subject-Action-Object(SAO) structures.Design/methodology/approach: First, SAO structures were extracted fro... Purpose: This paper introduces an approach to technology evolution analysis using patent information based on Subject-Action-Object(SAO) structures.Design/methodology/approach: First, SAO structures were extracted from patent documents and were cleaned. Second, several dimension-reduction techniques were used to generate technology topics. Then, the hierarchical relationships between technology topics were calculated based on patent clustering. Finally, technology evolution maps were drawn by adding a timeline.Findings: This approach can reveal technology evolution processes from multiple perspectives than other approaches.Research limitations: The semantic annotation of an SAO type is not very accurate and the semantic types of technology topics need to be enriched.Practical implications: The approach can be applied to draw technology evolution maps using different types of technology topics such as problem or solution.Originality/value: This approach offers an analytical dimension and more details than existing techniques, and it helps identify fundamental and emerging technologies more accurately and comprehensively. 展开更多
关键词 Technology evolution Patent analysis SAO Feature d
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Steady Fault Characteristic Analysis of a Missile Power System Based on a Differential Evolution Algorithm 被引量:3
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作者 XUZhi-gao GUANZheng-xi MAJing 《International Journal of Plant Engineering and Management》 2005年第2期95-99,共5页
The differential evolution (DE) algorithm is applied to solving themodels''equations of a whole missile power system, and the steady fault characteristics of the wholesystem are analyzed. The DE algorithm is r... The differential evolution (DE) algorithm is applied to solving themodels''equations of a whole missile power system, and the steady fault characteristics of the wholesystem are analyzed. The DE algorithm is robust, requires few control variables, is easy to use andlends itself very well to parallel computation. Calculation results indicate that the DE algorithmsimulates faults of a missile power system very well. 展开更多
关键词 liquid missile power system differential evolution algorithm faultscharacteristic analysis
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Illustrative Application of the 2<sup>nd</sup>-Order Adjoint Sensitivity Analysis Methodology to a Paradigm Linear Evolution/Transmission Model: Reaction-Rate Detector Response 被引量:2
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期382-397,共16页
This work continues the illustrative application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a benchmark mathematical model that can simulate th... This work continues the illustrative application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a benchmark mathematical model that can simulate the evolution and/or transmission of particles in a heterogeneous medium. The model response considered in this work is a reaction-rate detector response, which provides the average interactions of particles with the respective detector or, alternatively, the time-average of the concentration of a mixture of substances in a medium. The definition of this model response includes both uncertain boundary points of the benchmark, thereby providing both direct and indirect contributions to the response sensitivities stemming from the boundaries. The exact expressions for the 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to the boundary and model parameters obtained in this work can serve as stringent benchmarks for inter-comparing the performances of all (deterministic and statistical) sensitivity analysis methods. 展开更多
关键词 Second-Order Adjoint Comprehensive Sensitivity analysis Methodology (2nd-CASAM) evolution Benchmark Model Exact and Efficient Computation of First- and Second-Order Response Sensitivities
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Illustrative Application of the 2<sup>nd</sup>-Order Adjoint Sensitivity Analysis Methodology to a Paradigm Linear Evolution/Transmission Model: Point-Detector Response 被引量:2
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作者 Dan Gabriel Cacuci 《American Journal of Computational Mathematics》 2020年第3期355-381,共27页
This work illustrates the application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a mathematical model that can simulate the evolution and/or tr... This work illustrates the application of the “Second Order Comprehensive Adjoint Sensitivity Analysis Methodology” (2<sup>nd</sup>-CASAM) to a mathematical model that can simulate the evolution and/or transmission of particles in a heterogeneous medium. The model response is the value of the model’s state function (particle concentration or particle flux) at a point in phase-space, which would simulate a pointwise measurement of the respective state function. This paradigm model admits exact closed-form expressions for all of the 1<sup>st</sup>- and 2<sup>nd</sup>-order response sensitivities to the model’s uncertain parameters and domain boundaries. These closed-form expressions can be used to verify the numerical results of production and/or commercial software, e.g., particle transport codes. Furthermore, this paradigm model comprises many uncertain parameters which have relative sensitivities of identical magnitudes. Therefore, this paradigm model could serve as a stringent benchmark for inter-comparing the performances of all deterministic and statistical sensitivity analysis methods, including the 2<sup>nd</sup>-CASAM. 展开更多
关键词 Second-Order Adjoint Comprehensive Sensitivity analysis Methodology (2nd-CASAM) evolution Benchmark Model Exact and Efficient Computation of First- and Second-Order Response Sensitivities
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Rediscovery and analysis of Phytophthora carbohydrate esterase(CE) genes revealing their evolutionary diversity
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作者 QIAN Kun LI Deng-hui +5 位作者 LIN Run-mao SHI Qian-qian MAO Zhen-chuan YANG Yu-hong FENG Dong-xin XIE Bing-yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第4期878-891,共14页
A continuous co-evolutionary arms-race between pathogens and their host plants promotes the development of pathogenic factors by microbes, including carbohydrate esterase(CE) genes to overcome the barriers in plant ce... A continuous co-evolutionary arms-race between pathogens and their host plants promotes the development of pathogenic factors by microbes, including carbohydrate esterase(CE) genes to overcome the barriers in plant cell walls. Identification of CEs is essential to facilitate their functional and evolutionary investigations; however, current methods may have a limit in detecting some conserved domains, and ignore evolutionary relationships of CEs, as well as do not distinguish CEs from proteases. Here, candidate CEs were annotated using conserved functional domains, and orthologous gene detection and phylogenetic relationships were used to identify new CEs in 16 oomycete genomes, excluding genes with protease domains. In our method, 41 new putative CEs were discovered comparing to current methods, including three CE4, 14 CE5, eight CE12, five CE13, and 11 CE14. We found that significantly more CEs were identified in Phytophthora than in Hyaloperonospora and Pythium, especially CE8, CE12, and CE13 that are putatively involved in pectin degradation. The abundance of these CEs in Phytophthora may be due to a high frequency of multiple-copy genes, supporting by the phylogenetic distribution of CE13 genes, which showed five units of Phytophthora CE13 gene clusters each displaying a species tree like topology, but without any gene from Hyaloperonospora or Pythium species. Additionally, diverse proteins associated with products of CE13 genes were identified in Phytophthora strains. Our analyses provide a highly effective method for CE discovery, complementing current methods, and have the potential to advance our understanding of function and evolution of CEs. 展开更多
关键词 PHYTOPHTHORA carbohydrate esterase gene prediction comparative genomic analysis evolution DIVERSITY
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Bayesian Coalescent Analysis of the Intra-Host Evolution of Hepatitis C Virus: Memory Genomes and Clinical Implications
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作者 Ricardo Recarey Juan Cristina 《Natural Science》 2014年第9期615-627,共13页
Genetic variability plays a key role in the biology and medical treatment of RNA viruses. As an RNA virus, Hepatitis C virus (HCV) replicate as complex distributions of closely related genomes termed viral quasispecie... Genetic variability plays a key role in the biology and medical treatment of RNA viruses. As an RNA virus, Hepatitis C virus (HCV) replicate as complex distributions of closely related genomes termed viral quasispecies. The behavior of the evolving HCV quasispecies population is influenced by the ensemble of mutants that compose the viral population. One such influence is the presence of minority subpopulations, termed memory genomes, in the mutant spectra. Biologically relevant mutants have been previously observed to be present as memory genomes in RNA viral populations. For that reason, an in-depth analysis of HCV quasispecies populations is crucial for our understanding viral evolution, drug resistance and therapy outcome. Recently developed next-generation sequencing (NGS) platforms make it possible to investigate viral quasispecies at much greater detail. In order to gain insight into these matters, we have performed a Bayesian coalescent analysis of hypervariable region 1 (HVR1) sequences of a HCV quasispecies population circulating in a chronic patient, recently obtained by ultra-deep sequencing. The results of these studies revealed a mean rate of evolution of HCV HVR1 of the intra-host quasispecies population of 4.80 × 10-2 amino acid substitutions/site/year. A sharp and rapid diversification of the HCV quasispecies isolated from the patient in three different sub-populations was observed. The most abundant sequence in the quasispecies population was not found to be the center of a tight and complex network around this sequence, suggesting that the quasispecies population as a whole efficiently explore a wide sequence space. Co-evolution of relevant amino acid sites had been identified in the HVR1. This speaks of the possible roll of these residues in HVR1 to allow the virus to shift between combinations of residues to escape the immune system while retaining its structure and functions. The results of these studies highlight the importance of minority genomes in HCV population history and evolution, the mutant clouds as reservoirs of phenotypic and genetic variants for virus adaptability, as well as the roll of the mutant spectra to overcome selective constraints. 展开更多
关键词 Hepatitis C Virus evolution BAYESIAN COALESCENT analysis QUASISPECIES
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Population Distribution Evolution Characteristics and Shift Growth Analysis in Shiyang River Basin
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作者 Minzhi Chen Peizhen Wang Li Chen 《International Journal of Geosciences》 2014年第11期1395-1403,共9页
In recent years, the population size and scale of the Shiyang River Basin unceasingly expanding lead to a series of ecological environment: surface water reducing, land desertification and Ground water levels fall, et... In recent years, the population size and scale of the Shiyang River Basin unceasingly expanding lead to a series of ecological environment: surface water reducing, land desertification and Ground water levels fall, etc. Research evolution characteristics of population distribution and migration growth of Shiyang River Basin contribute to river water resources and the industrial development of the comprehensive management. The article using the distribution of population structure index, population distribution center of gravity model and the population migration growth analysis model analyzes the distribution of the population evolution characteristics and population migration growth characteristics of Shiyang River Basin in 2000 to 2010. The results show that: 1) Considering Shiyang River Basin, population density is generally low, population distribution difference is bigger and concentration distribution in the middle corridor plain and three big population distribution center of Minqin oasis area, presenting a “point-areas-ribbon” structure characteristics. 2) The population distribution trend of Shiyang River Basin is constantly concentration, but the change is slow;the population distribution of Minqin is in the highest concentration degree, but the trend has been declining. 3) The focus of population density in river basin locates in Liangzhou district of Daliu country;in ten years, it migrates about 1209 m to southwest Wuwei City direction, but migration along the direction things is bigger than the north and south direction. The focus of population density and the basin geometry center is far away. 4) For ten years, at the township for basic statistics unit, each level population migration change within the overall is not significant: township level > prefecture-level cities level > counties level. 5) For ten years, there are significant changes in population migration between watershed township units, Wuwei City and Gulang Town are the two main concentrations of population centers. 展开更多
关键词 Shiyang RIVER BASIN POPULATION Distribution evolution Characteristics SHIFT GROWTH analysis
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Simulation and experimental analysis of melt pool evolution in laser engineered net shaping
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作者 Zhuangzhuang Mao Wei Feng +1 位作者 Ce Hao Zhanwei Liu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2022年第5期332-340,共9页
In this work,the evolution of melt pool under single-point and single-line printing in the laser engineered net shaping(LENS)process is analyzed.Firstly,the basic structure of the melt pool model of the LENS process i... In this work,the evolution of melt pool under single-point and single-line printing in the laser engineered net shaping(LENS)process is analyzed.Firstly,the basic structure of the melt pool model of the LENS process is established and the necessary assumptions are made.Then,the establishment process of the multi-physical field model of the melt pool is introduced in detail.It is concluded that the simulation model results are highly consistent with the online measurement experiment results in terms of melt pool profile,space temperature gradient,and time temperature gradient.Meanwhile,some parameters,such as the 3D morphology and surface fluid field of the melt pool,which are not obtained in the online measurement experiment,are analyzed.Finally,the influence of changing the scanning speed on the profile,peak temperature,and temperature gradient of the single-line melt pool is also analyzed,and the following conclusions are obtained:With the increase in scanning speed,the profile of the melt pool gradually becomes slender;The relationship between peak temperature and scanning speed is approximately linear in a certain speed range;The space temperature gradient at the tail of the melt pool under different scanning speeds hardly changes with the scanning speed,and the time temperature gradient at the tail of the melt pool is in direct proportion to the scanning speed. 展开更多
关键词 Additive manufacturing Laser engineered net shaping Melt pool evolution Simulation analysis Temperature measurement
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Evolution Analysis and Balanced Coexistence of Ecological Chain
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作者 Daping LIANG 《Meteorological and Environmental Research》 CAS 2020年第2期15-19,24,共6页
Based on evolution history of earth ecosystem,by studying and analyzing three development stages of natural ecological chain and man-made ecological chain before and after the birth of human beings on the earth,and co... Based on evolution history of earth ecosystem,by studying and analyzing three development stages of natural ecological chain and man-made ecological chain before and after the birth of human beings on the earth,and comparing the energy consumption of human activities and the impact of environmental factors related to natural ecological chain in these stages,following characteristics are found. First,the increasing intelligence of human activities has an increasing impact on the natural ecological chain. Second,the increasing energy consumption of human activities is directly proportional to the degree of natural ecological impact. Third,the traditional production mode of consumption type and the development speed of science and technology are inversely proportional to the change cycle of man-made ecological chain and directly proportional to the degree of ecological crisis. An ecosystem has the ability to regulate,but it has its limits. Beyond this limit,the ecological balance will be destroyed. So,the goal is to transform into a circular type of modern production mode and scientific and technological development as soon as possible,and to shift to a balance between human material requirements and the maintenance and stability of the environment,namely the era of ecological chain of coexistence where nature and human beings are highly harmonious. 展开更多
关键词 ECOLOGICAL CHAIN evolution analysis BALANCED COEXISTENCE
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Evolution and prospect of China's rural development policy: A policy text analysis of the No.1 Central Documents
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作者 WANG Qiang 《Ecological Economy》 2018年第4期268-281,共14页
By combing 20 documents of the Central Committee on the historical evolution of rural development policies since 1982, we hold that historical evolution has undergone reforms, adjustments, modernization developments a... By combing 20 documents of the Central Committee on the historical evolution of rural development policies since 1982, we hold that historical evolution has undergone reforms, adjustments, modernization developments and new ideas, and the path of reform experienced economic recovery, industrial nurturing agriculture, agriculture modernization and rural revitalization. The study found that: farmers' income has always been the focus of attention; agricultural production has shifted from total demand to green ecology; urban and rural resource elements are not well-organized, resulting in internal contradictions. The implementation of the rural revitalization strategy is an important measure to fundamentally solve the rural development problems in the new era. 展开更多
关键词 the No.1 CENTRAL Document text analysis rural development evolution PROSPECT
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Spatial-temporal Evolution Analysis on Land Use Multifunctionality in the China-Vietnam Border Area
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作者 HUANG Tianneng WANG Nian 《Chinese Geographical Science》 SCIE CSCD 2022年第6期995-1012,共18页
Exploring the spatial and temporal evolution characteristics of the border land use multifunctionality(LUMF)provides insights for taking advantage of border land use and optimizing border land use policies.Based on th... Exploring the spatial and temporal evolution characteristics of the border land use multifunctionality(LUMF)provides insights for taking advantage of border land use and optimizing border land use policies.Based on the improved Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS)mode,this study identifies and evaluates the LUMFs in the China-Vietnam border area between 2000 and 2018 from the perspectives of agricultural production,social security,ecological service,landscape recreation,and national security.The results show that:1)The comprehensive land use functions in most counties and cities continued to be improved.2)The comprehensive land use function exhibits remarkable spatial divergence and aggregation characteristics.The high-value area of the agricultural production function and social security function evolves from the east to the west.In addition,the spatial evolution of ecological service function is complicated,without an obvious spatial divergence and aggregation pattern.The landscape recreation function shows different spatial differentiation characteristics in the early and middle stage,and forms a large cluster in the later stage.Finally,the spatial evolution pattern of the national security function is significant.3)Designing differentiated border land policies,improving border land use security,and establishing a long-term mechanism for ecological protection and ecological compensation can aid in optimizing the LUMF level in the border area. 展开更多
关键词 land use multifunctionality spatial-temporal evolution characteristics improved Technique for Order Preference by Similarity to an Ideal Solution(TOPSIS) spatial analysis China-Vietnam border area
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Analysis on the Evolution Path of Transformation of Manufacturing Enterprises through Servitization——A Case Study Based on ShaanGu Group
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作者 Tongjing Zhang Zheng He Xiaohong Yang 《管理科学与研究(中英文版)》 2022年第11期190-199,共10页
Service-oriented manufacturing is an emerging innovative development model,and its core is the deep integration of products and services.It has become a hot issue in current research.In order to deeply explore the evo... Service-oriented manufacturing is an emerging innovative development model,and its core is the deep integration of products and services.It has become a hot issue in current research.In order to deeply explore the evolution path of servitization transformation of manufacturing enterprises,ShaanGu Group is taken as a case,and discusses practical application of service-oriented manufacturing model in different development processes of ShaanGu Group.Thus,four stages of transformation of ShaanGu Group through servitization are summarized:specialized after-sales service stage,rental service stage,engineering complete service stage and financial service stage.Through comparative research,it is found that general evolution path of manufacturing enterprises to service transformation is:the primary stage(providing product-oriented product service system)→the intermediate stage(providing application-oriented product service system)→the advanced stage(providing utility-oriented product service system)→the completed stage(providing pure service).On this basis,some suggestions are provided for manufacturing enterprises to integrate productive services in the process of transformation. 展开更多
关键词 Service-Oriented Manufacturing Case analysis evolution Path Product Service System Productive Services
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