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Micro Evolutionary Processes and Adaptation
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作者 SHADMANOV R K RUBAN I N VOROPAEVA N L SHADMANOVA A R 《棉花学报》 CSCD 北大核心 2008年第S1期112-,共1页
It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.Ther... It would be well to note that in the absence of clear data about the formation of adaptation systems,or mechanisms of their occurrence,all that is recognized is the realization of the micro evolutionary processes.There is no well-defined connection between information exchange and formation 展开更多
关键词 Micro evolutionary processes and Adaptation
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The Evolutionary History of Ore-forming Processes of Metallic Ore Deposits in Northern Guangxi
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作者 Chen Yuchuan, Mao Jinwen and Wang Ping’an Chinese Academy of Geological Sciences, Beijing Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第2期155-170,共16页
The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis ... The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis shows features of polycyclic spiral evolution throughout the geological history. As far as various cycles are concerned, mantle-derived ore substances were reduced while crust-derived ore substances increased from early to late timesfin the whole geological evolutionary history, mantle-derived substances decreased gradually while crust-derived ones increased. Meanwhile ore element associations became more and more varied. In terms of space, mineralization migrated from the old basement outwards, i.e. from west to east during the Precambrian, and from north to south during the Phanerozoic, and again from east to west during the Yanshanian. 展开更多
关键词 metallogenic series evolutionary history of ore - forming processes metallogenic model rare metal- nonferrous metal deposit
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A stability evaluation method for deep-seated toppling in the upper Lancang river,Southwestern China
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作者 Yibing Ning Huiming Tang +3 位作者 Jianbing Peng Yanjun Shen John V.Smith Bocheng Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2388-2410,共23页
Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in depth.The slope deformation is initiated by river downcutting and evolves distinctive characteris... Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in depth.The slope deformation is initiated by river downcutting and evolves distinctive characteristics with a depth of river incision.In this study,we propose a system for evaluating the stability of deep-seated toppled slopes in different evolutionary stages.This system contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation methods.Based on the mechanical and kinematic analysis of slope blocks,the specific stage of slope movement can be identified in the field through outcrop mapping,in situ tests,surface displacement monitoring,and adit and borehole explorations.The stability evaluation methods are established based on the limiting equilibrium theory and the strain compatibility between the undisturbed zone and the toppled zone.Finally,several sample slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation system.The results indicate that intense tectonic activity and rapid river incision lead to a maximum principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deformations along the river valley.When considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deformation can be recognized by the layer symmetry configuration after the free rotation of the deflected layers.Intensely toppled rock blocks mainly suffer sliding failures beyond the layer symmetry condition.The factor of safety of the K73 rockslide decreased from 1.17 to 0.87 by considering the development of the potential sliding surface and the toesaturated zone. 展开更多
关键词 Stability evaluation Deep-seated toppling evolutionary process Reservoir impoundment Rock slope
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Numerical simulation study of the failure evolution process and failure mode of surrounding rock in deep soft rock roadways 被引量:15
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作者 Meng Qingbin Han Lijun +3 位作者 Xiao Yu Li Hao Wen Shengyong Zhang Jian 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第2期209-221,共13页
Based on the safety coefficient method,which assigns rock failure criteria to calculate the rock mass unit,the safety coefficient contour of surrounding rock is plotted to judge the distribution form of the fractured ... Based on the safety coefficient method,which assigns rock failure criteria to calculate the rock mass unit,the safety coefficient contour of surrounding rock is plotted to judge the distribution form of the fractured zone in the roadway.This will provide the basis numerical simulation to calculate the surrounding rock fractured zone in a roadway.Using the single factor and multi-factor orthogonal test method,the evolution law of roadway surrounding rock displacements,plastic zone and stress distribution under different conditions is studied.It reveals the roadway surrounding rock burst evolution process,and obtains five kinds of failure modes in deep soft rock roadway.Using the fuzzy mathematics clustering analysis method,the deep soft surrounding rock failure model in Zhujixi mine can be classified and patterns recognized.Compared to the identification results and the results detected by geological radar of surrounding rock loose circle,the reliability of the results of the pattern recognition is verified and lays the foundations for the support design of deep soft rock roadways. 展开更多
关键词 Deep soft rock roadway evolutionary process Failure model Numerical simulation Model recognition
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An Evolutionary Economic Geography Perspective on Types of Operation Development in West Lake, China 被引量:3
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作者 YANG Xingzhu ZHA Yanyan +1 位作者 LU Lin YANG Yang 《Chinese Geographical Science》 SCIE CSCD 2017年第3期482-496,共15页
The types of operation play a key role in facilitating tourism consumption and economic development in a tourism destination. By adopting evolutionary economic geography theory, the paper analyzes the types of operati... The types of operation play a key role in facilitating tourism consumption and economic development in a tourism destination. By adopting evolutionary economic geography theory, the paper analyzes the types of operation in West Lake Scenic Area from 1978 to 2013. First, an evolution process consisting of four stages is underpinned, and they are: the new establishment stage, the preliminary development stage, the speedup development stage, and the stabilized maturity stage. Specifically, the distinct characteristics associated with operation types are compared and evaluated at different stages throughout the process. The evolution trees are introduced to scrutinize types of operation development. The results of evolution trees demonstrate the substantial increase in both numbers and types. Second, by applying GIS spatial analysis, the paper also analyzes the spatial evolution characteristics on the types of operation, and the results unveil the co-existence of centripetal and centrifugal forces: the processes of spatial agglomeration and spatial dispersion. More specifically, we recognize the spatial process includes the emergence of node and concentration(1978–1995), the sparse distribution and intensity reduction(1996–2002), the patchy distribution and spatial agglomeration intensification(2003–2008), the dispersed distribution and core area agglomeration(2009–2013). Lastly, path dependence on resource endowment, government and market innovation, knowledge learning and spillover can reasonably explain the types of operation evolution. In conclusion, the evolutionary economic geography theories provide new theoretical and empirical perspectives for tourism policy analysis. At the same time, our comprehensive evidences impart more comprehensive insights and offer useful managerial and policy implications. 展开更多
关键词 types of operation evolutionary economic geography spatial process West Lake China
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Geochronology and Tectonic Evolution of the West Section of the Jiangnan Orogenic Belt 被引量:4
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作者 ZHANG Heng LI Tingdong +5 位作者 XIE Ying ZHANG Chuanheng GAO Linzhi GENG Shufang CHEN Tingyu YOU Guoqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第5期1497-1515,共19页
As an important part of South China Old Land, the Jiangnan Orogenic Belt plays a significant role in explaining the assembly and the evolution of the Upper Yangtze Block and Cathaysia, as well as the structure and gro... As an important part of South China Old Land, the Jiangnan Orogenic Belt plays a significant role in explaining the assembly and the evolution of the Upper Yangtze Block and Cathaysia, as well as the structure and growth mechanism of continental lithosphere in South China.The Lengjiaxi and the Banxi groups are the base strata of the west section of the Jiangnan Orogenic Belt.Thus, the research of geochronology and tectonic evolution of the Lengjiaxi and the Banxi groups is significant.The maximum sedimentary age of the Lengjiaxi Group is ca.862 Ma, and the minimum is ca.822 Ma.The Zhangjiawan Formation, which is situated in the upper part of the Banxi Group is ca.802 Ma.The Lengjiaxi Group and equivalent strata should thus belong to the Neoproterozoic in age.The Jiangnan Orogenic Belt consisting of the Lengjiaxi and the Banxi groups as important constituents is not a Greenville Orogen Belt(1.3 Ga–1.0 Ga).The Jiangnan Orogenic Belt is a recyclic orogenic belt, and the prototype basin is a foreland basin with materials derived from the southwest and the sediments belong to the active continental sedimentation.By combining large amounts of dating data of the Lengjiaxi and the Banxi groups as well as equivalent strata, the evolutionary model of the western section of the Jiangnan Orogenic Belt is established as follows: Before 862 Ma, the South China Ocean was subducted beneath the Upper Yangtze Block, while a continental island arc was formed on the side near the Upper Yangtze Block.The South China Ocean was not closed in this period.From 862 Ma to 822 Ma, the Upper Yangtze Block was collided with Cathaysia; and sediments began to be deposited in the foreland basin between the two blocks.The Lengjiaxi Group and equivalent strata were thus formed and the materials might be derived from the recyclic orogenic belt.From 822 Ma to 802 Ma, Cathaysia continued pushing to the Upper Yangtze Block, experienced the Jinning-Sibao Movement(Wuling Movement); as result, the folded basement of the Jiangnan Orogenic Belt was formed.After 802 Ma, Cathaysia and the Upper Yangtze Block were separated from each other, the Nanhua rift basin was formed and began to receive the sediments of the Banxi Group and equivalent strata.These large amounts of dating data and research results also indicate that before the collision of the Upper Yangtze Block with Cathaysia, materials of the continental crust became less and less from the southwest to the east in the Jiangnan Orogeneic Belt; only island arc and neomagmatic arc were developed in the eastern section.Ocean-continent subduction or continent-continent subduction took place in the western and southern sections, while intra-oceanic subduction occurred in the eastern section.Comprehensive analyses on U-Pb ages and Hf model ages of zircons, the main provenance of the Lengjiaxi Group is Cathaysia. 展开更多
关键词 zircon U-Pb age evolutionary process Lengjiaxi Group Banxi Group Jinning-Sibao Movement(Wuling Movement) Jiangnan Qrogenic Belt
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Exploring potentialities of avian genomic research in Nepalese Himalayas
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作者 Prashant Ghimire Nishma Dahal +2 位作者 Ajit KKarna Surendra Karki Sangeet Lamichhaney 《Avian Research》 SCIE CSCD 2021年第4期727-738,共12页
Nepal,a small landlocked country in South Asia,holds about 800 km of Himalayan Mountain range including the Earth's highest mountain.Within such a mountain range in the north and plain lowlands in the south,Nepal ... Nepal,a small landlocked country in South Asia,holds about 800 km of Himalayan Mountain range including the Earth's highest mountain.Within such a mountain range in the north and plain lowlands in the south,Nepal provides a habitat for about 9%of global avian fauna.However,this diversity is underrated because of the lack of enough studies,especially using molecular tools to quantify an-d understand the distribution patterns of diversity.In this study,we reviewed the studies in the last two decades(20002019)that used molecular methods to study the biodiversity in Nepal to examine the ongoing research trend and focus.Although Nepalese Himalaya has many opportunities for cutting-edge molecular research,our results indicated that the rate of genetic/genomic studies is much slower compared to the regional trends.We found that genetic research in Nepal heavily relies on resources from international institutes and that too is mostly limited to research on species monitoring,distribution,and taxonomic validations.Local infrastructures to carry out cutting-edge genomic research in Nepal are still in their infancy and there is a strong need for support from national/international scientists,universities,and governmental agencies to expand such genomic infrastructures in Nepal.We particularly highlight avian fauna as a potential future study system in this region that can be an excellent resource to explore key biological questions such as understanding eco-physiology and molecular basis of organismal persistence to changing environment,evolutionary processes underlying divergence and speciation,or mechanisms of endemism and restrictive distribution of species. 展开更多
关键词 Avian fauna evolutionary process GENOMICS HIMALAYAS Nepal
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Time Dependent Gaussian Equivalent Linearization of Duffing Oscillator Using Continuous Wavelet Transform
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作者 Arunasis Chakraborty Prateek Mittal Sabarethinam Kameshwar 《Journal of Civil Engineering and Architecture》 2013年第8期1006-1017,共12页
Evolutionary response analysis of Duffing oscillator using Gaussian equivalent linearization in wavelet based time-frequency frame work is presented here. Cubic (i.e., odd type) non-linearity associated with stiffne... Evolutionary response analysis of Duffing oscillator using Gaussian equivalent linearization in wavelet based time-frequency frame work is presented here. Cubic (i.e., odd type) non-linearity associated with stiffness and damping is modeled. The goal of this research is to develop the mathematical model of an equivalent linear system which is applicable for different non-stationary input processes (i.e., either summation of amplitude modulated stationary orthogonal processes or digitally simulated non-stationary processes). The instantaneous parameters of the ELTVS (equivalent linear time varying system) are evaluated by minimizing the error between the displacements of non-linear and equivalent linear systems in wavelet domain. For this purpose, three different basis functions (i.e., Mexican Hat, Morlet and a modified form of Littlewood-Paley) are used. The unknown parameters (i.e., natural frequency and damping) of the ELTVS are optimized in stochastic least square sense. Numerical results are presented for different types of input to show the applicability and accuracy of the proposed wavelet based linearization technique. 展开更多
关键词 Statistical linearization wavelet analysis Duffing oscillator evolutionary process.
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Progress of research on transportation geography in China 被引量:2
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作者 金凤君 王成金 +4 位作者 曹有挥 曹小曙 王姣娥 戴特奇 焦敬娟 《Journal of Geographical Sciences》 SCIE CSCD 2016年第8期1067-1080,共14页
As an important branch of human geography, transportation geography has experienced three periods of evolution: foundation, systematization, and rapid development of the discipline. It has gradually become a relativel... As an important branch of human geography, transportation geography has experienced three periods of evolution: foundation, systematization, and rapid development of the discipline. It has gradually become a relatively mature discipline. During the period 1930– 1980, the development of transportation geography consisted mainly of the publication of theoretical texts. During 1980–2000, it gradually became a systematic discipline. Since the start of the 21 st century, transportation geography has focused mainly on exploring the impacts of transportation on socio-economic development. Currently, studies on transportation geography have led to significant developments in a number of areas, including transportation theory, facility distribution and planning, transportation flows and network analysis, evaluation of transport modes, transportation planning, and simulation and assessment of urban transportation. Such studies have also enriched human geography research, provided a wider geographical overview and elucidated the development mechanism of transportation, as well as helped to understand the impacts of transport development on socio-economic systems. Some findings obtained by geographers have been widely used in transportation geography and related fields, including the four basic laws of transportation generation, the hub–spoke mode of transport organization, the subordinating and guiding functions of transportation on socio-economic development, regional transport dominance measures, accessibility measures, and spatial organization of port systems. 展开更多
关键词 transportation geography evolutionary process research field academic contribution development trend
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