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Regional difference and dynamic evolution of development quality of power industry in China
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作者 Sha Yu Yongjian Pu +2 位作者 Lefeng Shi Hao Yu Yixiang Huang 《Chinese Journal of Population,Resources and Environment》 2023年第1期1-12,共12页
To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the... To achieve the goals of carbon peaking and carbon neutrality and maintain high-quality economic growth,China is currently striving to improve the quality of development of its power sector.In this regard,revealing the regional differences and evolutionary trends in the development quality of China’power sector has a high value to inspire the next improvement direction toward how to integrate regional power recourses to an overall optimization level.Motived by this purpose,this paper uses the entropy method to evaluate the com‐prehensive and subsystem indices of the development quality of the power industry,and reveals their re‐gional differences and evolutionary trends with the help of the Dagum Gini coefficient and Kernel density es‐timation methods.The findings show that:There are obvious regional differences in the development quality of China’s power industry,and the differences are steadily declining in all regions except the West.Regional differences are mainly derived from inter-regional differences,with the largest inter-regional differences in the East-Northeast region.Intra-regional differences show a distribution pattern of East>West>North‐east>Center. 展开更多
关键词 Development quality of power industry Regional difference The Dagum Gini dynamic evolution Kernel density
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Dynamic evolution of shear rate-dependent behavior of rock discontinuity under shearing condition 被引量:2
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作者 GU Lin-lin WANG Zhen +2 位作者 ZHANG Feng GAO Fei WANG Xiao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第6期1875-1887,共13页
Rock blocks sliding along discontinuities can cause serious disasters,such as landslides,earthquakes,or rock bursts.The shear rate-dependent behavior is a typical time-dependent behavior of a rock discontinuity,and it... Rock blocks sliding along discontinuities can cause serious disasters,such as landslides,earthquakes,or rock bursts.The shear rate-dependent behavior is a typical time-dependent behavior of a rock discontinuity,and it is closely related to the stability of a rock block.To further study the shear rate-dependent behavior of rock discontinuities,shear tests with alternating shear rates(SASRs)were conducted on rock discontinuities with various surface morphologies.The dynamic evolution of the shear rate dependency was studied in detail based on the shear test results,and three stages were identified with respect to the shear stress and shear deformation states.The test results revealed that dynamic changes in shear stiffness and the energy storage abilities of the rock discontinuities occurred in relation to the shear rate-dependent behavior of crack growth,which increased with an increase in normal stress and/or the joint roughness coefficient.The stage of decreasing shear stiffness corresponded to a stage of noticeable shear rate-dependency,and the shear rate was found to have no influence on the initial crack stress. 展开更多
关键词 shear rate-dependent behavior rock discontinuity dynamic evolution initial crack stress
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Dynamic evolution patterns of the degree of ground resistivity anisotropy and the sets mogenic process 被引量:1
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作者 毛桐恩 胥广银 +2 位作者 范思源 赵明 孙景芳 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期200-205,共8页
Following a new train of thinking, this paper has explored first the potential information in the ground resistivitydata observed by the existing geoelectric observation system, investigated and proposed a new dimensi... Following a new train of thinking, this paper has explored first the potential information in the ground resistivitydata observed by the existing geoelectric observation system, investigated and proposed a new dimensionlessgeoelectric precursor factor, the degree of ground resistivity anisotropy, S, and studied the characteristics of dynamic evolution pattern of S during the seismogenic process. The results show that, during the seismogenic process, the degree of ground resistivity anisotropy (S) displays h process of 'normal' → 'abnormal strengthening(amplitude, range)' → 'abnormal weakening'→ 'earthquake occurrence'→ 'normal'. The earthquake wouldoccur at the time when the S value has entered the late stage of strengthening and turns to weaken and in the gradient belt on the margin ofS anomaly region. The dynamic evolution pattern ofS reflects the changes of the tectonicstress field during the seismogenic process. Therefore, it would be possible to trace the process of earthquake generation and occurrence from the dynamic evolution pattern ofS so as to service eaJ'thquake prediction. 展开更多
关键词 degree of ground resistivity anisotropy dynamic evolution pattern seismogenic process
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A Dynamic Evolution Model of Airline Networks
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作者 谢泽浚 张璐嫚 +1 位作者 邓盛锋 李炜 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第5期137-140,共4页
Empirical data show that most of the degree distribution of airline networks assume a double power law. In this work, firstly, we assume cities as sites, flight between two cities as an edge between two sites, and bui... Empirical data show that most of the degree distribution of airline networks assume a double power law. In this work, firstly, we assume cities as sites, flight between two cities as an edge between two sites, and build a dynamic evolution model for airline networks by improving the BA model, in which the conception of attractiveness plays a decisive role in the course of evolution of the networks. To this end, we discuss whether the attractiveness depends on the site label s or not separately, finally we obtain analytic degree distribution. As a result, if the attractiveness of a site is independent of the degree distribution of sites, which will follow the double power law, otherwise, it will be scale-free. Moreover, degree distribution depends on the parameters of the models, and some parameters aye more sensitive than others. 展开更多
关键词 A dynamic evolution Model of Airline Networks AS
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Collaboration strategy for software dynamic evolution of multi-agent system
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作者 李青山 褚华 +2 位作者 张曼 李敏 刁亮 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2629-2637,共9页
As the ability of a single agent is limited while information and resources in multi-agent systems are distributed, cooperation is necessary for agents to accomplish a complex task. In the open and changeable environm... As the ability of a single agent is limited while information and resources in multi-agent systems are distributed, cooperation is necessary for agents to accomplish a complex task. In the open and changeable environment on the Internet, it is of great significance to research a system flexible and capable in dynamic evolution that can find a collaboration method for agents which can be used in dynamic evolution process. With such a method, agents accomplish tasks for an overall target and at the same time, the collaborative relationship of agents can be adjusted with the change of environment. A method of task decomposition and collaboration of agents by improved contract net protocol is introduced. Finally, analysis on the result of the experiments is performed to verify the improved contract net protocol can greatly increase the efficiency of communication and collaboration in multi-agent system. 展开更多
关键词 multi-agent system dynamic evolution task decomposition collaboration
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Dynamic Evolution and Driving Forces of the Changes in Lakeside Wetlands in the Mongolian Plateau
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作者 WEN Yunhao WANG Xueming +9 位作者 LIU Huamin YU Hongbo NIU Feng FANG Haitao WEN Lu ZHUO Yi FU Ruiying BAI Yang XIAO Bowen WANG Lixin 《Journal of Resources and Ecology》 CSCD 2024年第5期1160-1174,共15页
Rapid climate change and human disturbance have caused serious damage and shrinkage of the wetlands in the Mongolian Plateau,posing severe challenges to environmental development.Based on remote sensing images and DEM... Rapid climate change and human disturbance have caused serious damage and shrinkage of the wetlands in the Mongolian Plateau,posing severe challenges to environmental development.Based on remote sensing images and DEM data,this study established a series of datasets for lakeside wetlands in the Mongolian Plateau in 2000,2010 and 2020,and investigated the dynamic evolution of lakeside wetlands in the Mongolian Plateau through spatial and temporal analyses.The results showed that in 2000,there were 564 lakes(>1 km^(2))in the Mongolian Plateau,with a total area of about 55216.47 km^(2).Compared with 2000,the area of lakes in 2010 was significantly reduced,and there was a significant increase in the number of woody marshes and a reduction in the number of herbaceous marshes.In 2020,the lakes in the central part of the Mongolian Plateau were smaller than in 2010.The areas of lakes in the western,southern and eastern regions were increasing,and the areas of herbaceous swamps,woody marshes and meadows were increasing overall.Lakes,bare land and saline-alkali land decreased overall.The degree of salinization was reduced over the study period.There was a significant correlation between the Adaptive Palmer Drought Index(scPDSI)and lake area.In the past two decades,the climatic factors and human activities of the Mongolian Plateau have profoundly affected the evolution of the lakeside wetlands.We should prioritize the protection of lakes and wetland resources in order to achieve the dynamic balance of wetland ecology. 展开更多
关键词 lakeside wetland Mongolian Plateau lacustrine shorenization dynamic evolution
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Uncovering the dynamic evolution of nucleotidebinding site-leucine-rich repeat(NBS-LRR) genes in Brassicaceae 被引量:9
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作者 Yan-Mei Zhang Zhu-Qing Shao +4 位作者 Qiang Wang Yue-Yu Hang Jia-Yu Xue Bin Wang Jian-Qun Chen 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2016年第2期165-177,共13页
Plant genomes harbor dozens to hundreds of nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes; however, the long-term evolutionary history of these resistance genes has not been fully understood, This study... Plant genomes harbor dozens to hundreds of nucleotide-binding site-leucine-rich repeat (NBS-LRR) genes; however, the long-term evolutionary history of these resistance genes has not been fully understood, This study focuses on five Brassicaceae genomes and the Carica papaya genome to explore changes in NBS-LRR genes that have taken place in this Rosid II lineage during the past 72 million years. Various numbers of NBS-LRR genes were identified from Arabidopsis lyrata (198), A. thaliana (165), Brassica rapa (204), Capsella rubella (127), Thellungiella salsuginea (88), and C. papaya (51). In each genome, the identified NBS-LRR genes were found to be unevenly distributed among chromosomes and most of them were clustered together. Phylogenetic analysis revealed that, before and after Brassicaceae speciation events, both toll/interleukin-1 receptor-NBS-LRR (TNL) genes and non-toll/interleukin-1 receptor-NBS-LRR (nTNL) genes exhibited a pattern of first expansion and then contraction, suggesting that both subclasses of NBS-LRR genes were responding to pathogen pressures synchronically. Further, by examining the gain/loss of TNL and nTNL genes at different evolutionary nodes, this study revealed that both events often occurred more drastically in TNL genes. Finally, the phylogeny of nTNL genes suggested that this NBS-LRR subclass is composed of two separate ancient gene types: RPW8-NBS-LRR and Coiled-coiI-N BS-LRR. 展开更多
关键词 dynamic evolution nucleotide-binding site-leucine-rich repeat gene phylogenetic relationship plant disease resistance
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Aerodynamic airfoil design using the Euler equations based on the dynamic evolution method and the control theory 被引量:5
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作者 GAO YingYing HE Feng SHEN MengYu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第4期697-702,共6页
Based on the idea of adjoint method and the dynamic evolution method,a new optimum aerodynamic design technique is presented in this paper.It can be applied to the optimum problems with a large number of design variab... Based on the idea of adjoint method and the dynamic evolution method,a new optimum aerodynamic design technique is presented in this paper.It can be applied to the optimum problems with a large number of design variables and is time saving.The key of the new method lies in that the optimization process is regarded as an unsteady evolution,i.e.,the optimization is executed,simultaneously with solving the unsteady flow governing equations and adjoint equations.Numerical examples for both the inverse problem and drag minimization using Euler equations have been presented,and the results show that the method presented in this paper is more efficient than the optimum methods based on the steady flow solution and the steady solution of adjoint equations. 展开更多
关键词 Euler equations aerodynamic optimization dynamic evolution adjoint method
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Dynamic evolution trend of comprehensive transportation green efficiency in China:From a spatio-temporal interaction perspective 被引量:2
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作者 MA Qifei JIA Peng +1 位作者 SUN Caizhi KUANG Haibo 《Journal of Geographical Sciences》 SCIE CSCD 2022年第3期477-498,共22页
It is urgent and important to explore the dynamic evolution in comprehensive transportation green efficiency(CTGE)in the context of green development.We constructed a social development index that reflects the social ... It is urgent and important to explore the dynamic evolution in comprehensive transportation green efficiency(CTGE)in the context of green development.We constructed a social development index that reflects the social benefits of transportation services,and incorporated it into the comprehensive transportation efficiency evaluation framework as an expected output.Based on the panel data of 30 regions in China from 2003-2018,the CTGE in China was measured using the slacks-based measure-data envelopment analysis(SBM-DEA)model.Further,the dynamic evolution trends of CTGE were determined using the spatial Markov model and exploratory spatio-temporal data analysis(ESTDA)technique from a spatio-temporal perspective.The results showed that the CTGE shows a U-shaped change trend but with an overall low level and significant regional differences.The state transition of CTGE has a strong spatial dependence,and there exists the phenomenon of“club convergence”.Neighbourhood background has a significant impact on the CTGE transition types,and the spatial spillover effect is pronounced.The CTGE has an obvious positive correlation and spatial agglomeration characteristics.The geometric characteristics of the LISA time path show that the evolution process of local spatial structure and local spatial dependence of China’s CTGE is stable,but the integration of spatial evolution is weak.The spatio-temporal transition results of LISA indicate that the CTGE has obvious transfer inertness and has certain path-dependence and spatial locking characteristics,which will become the major difficulty in improving the CTGE. 展开更多
关键词 comprehensive transportation green efficiency spatio-temporal interaction dynamic evolution trend spatial markov model exploratory spatio-temporal data analysis
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Dynamic evolution of nitrogen and oxygen dual-coordinated single atomic copper catalyst during partial oxidation of benzene to phenol 被引量:1
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作者 Weiming Chen Hongqiang Jin +3 位作者 Feng He Peixin Cui Changyan Cao Weiguo Song 《Nano Research》 SCIE EI CSCD 2022年第4期3017-3025,共9页
Single atom catalysts(SACs)with metal_(1)-N_(x)sites have shown promising activity and selectivity in direct catalytic oxidation of benzene to phenol.The reaction pathway is considered to be involving two steps,includ... Single atom catalysts(SACs)with metal_(1)-N_(x)sites have shown promising activity and selectivity in direct catalytic oxidation of benzene to phenol.The reaction pathway is considered to be involving two steps,including a H_(2)O_(2)molecule dissociated on the metal single site to form the(metal_(1)-N_(x))=O active site,and followed by the dissociation of another H_(2)O_(2)on the other side of metal atom to form O=(metal_(1)-N_(x))=O intermediate center,which is active for the adsorption of benzene molecule via the formation of a C-O bond to form phenol.In this manuscript,we report a Cu SAC with nitrogen and oxygen dual-coordination(Cu1-N3O1 moiety)that doesn’t need the first H_(2)O_(2)activation process,as verified by both experimental and density function theory(DFT)calculations results.Compared with the counterpart nitrogen-coordinated Cu SAC(denoted as Cu1/NC),Cu SAC with nitrogen and oxygen dual-coordination(denoted as Cu1/NOC)exhibits 2.5 times higher turnover frequency(TOF)and 1.6 times higher utilization efficiency of H_(2)O_(2).Particularly,the coordination number(CN)of Cu atom in Cu1/NOC maintains four even after H_(2)O_(2)treatment and reaction.Combining DFT calculations,the dynamic evolution of single atomic Cu with nitrogen and oxygen dualcoordination in hydroxylation of benzene is proposed.These findings provide an efficient route to improve the catalytic performance through regulating the coordination environments of SACs and demonstrate a new reaction mechanism in hydroxylation of benzene to phenol reaction. 展开更多
关键词 single atom catalyst coordination dynamic evolution benzene oxidation PHENOL
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Spatiotemporal evolution of ecosystem service value and topographic gradient effect in the Da-Xiao Liangshan Mountains in Sichuan Province,China 被引量:2
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作者 JIN Tao CHEN Yang +2 位作者 SHU Bo GAO Min QIU Jian 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2344-2357,共14页
The Da-Xiao Liangshan mountains are critical ecological function areas and essential ecological barriers in the upper reaches of the Yangtze River in China.This study selected a total of six periods of land use land c... The Da-Xiao Liangshan mountains are critical ecological function areas and essential ecological barriers in the upper reaches of the Yangtze River in China.This study selected a total of six periods of land use land cover(LULC)data from 1995 to 2020,to estimate the ecosystem service value(ESV)and analyzed its spatiotemporal evolution and topographic gradient divergence.The results showed that:(1)The ESV increased by 1.1 billion yuan,with an increase rate of 1.47%from 1995 to 2020.Two time periods,2005–2010 and 2015–2020,showed more significant increases than other periods.(2)The elevation and slope of mountainous areas determine the type of land use and further influence the spatial pattern of ESV.(3)Although woodland and grassland are the main land use types of the study area(more than 90%),the hydrological regulation function of the water area partially compensated for the impact of the encroachment of the built-up area on the ESV of grassland.(4)The spatial distribution of ESVs showed an inverted V-shaped characteristic as the topographic gradient increased,with the dominant position being the 5th topographic gradient zone.Finally,this study provided relevant recommendations for ecosystem protection and optimization.The findings of this study clarified the influence of topographical factors on the spatial differentiation of ESV and provided novel insights into ecosystem protection. 展开更多
关键词 Ecosystem service value(ESV) dynamic evolution Terrain gradient effect Spatial pattern Liangshan Yi region
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Features and physical proces of the dynamic evolution pattern of ground resistivity precursor front
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作者 毛桐恩 范思源 +1 位作者 余素荣 孙景芳 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1998年第5期72-79,共8页
In order to quantitatively describe the geoelectric precursor anomaly in the short-impending process of earthquakes, a new geoelectric precursor index — (monthly) relative change rate of ground resistivity, R ρ... In order to quantitatively describe the geoelectric precursor anomaly in the short-impending process of earthquakes, a new geoelectric precursor index — (monthly) relative change rate of ground resistivity, R ρ (t) , is designed. Using this index and choosing the internationally accepted ground resistivity data before the Tangshan M =7.8 earthquake of July 28, 1976, the features of dynamic evolution pattern of R ρ(t) are studied. The results show that: ① about 10~9 months before earthquake, the ground resistivity in a certain range around the epicentral region begins to display the anomaly of accelerating descent, and the rate of descent is higher in the epicentral region than in surrounding areas; ② with the shortening of countdown before earthquake, the R ρ(t) value in epicentral region increases gradually (ground resistivity value decreases at an increasing rate); ③ the R ρ(t) value has the epicentral area as a center and its contour lines propagate towards surrounding areas with the shortening of countdown before earthquake; ④after the R ρ(t) value in epicentral region has descended at increasing rate to reach an extremity [ R ρ(t) = (7.0], it turns to descend at decreasing rate (2~3 months) and earthquake occurs when it accelerates again. Meanwhile, earthquake occurs when the contour lines of R ρ(t) stop propagating towards surrounding areas and turn to shrink back (2~3 months later). Its physical process can be explained by the″ swollen hypothesis″ of Prof. Fu and the theory of ″Slip-weakening and rockmass instability″ of Mei, Niu, et al .. 展开更多
关键词 short-impending process of earthquake ground resistivity precursor front dynamic evolution physical process
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Dynamic aggregation evolution of competitive societies of cooperative and noncooperative agents
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作者 林振权 叶高翔 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期572-586,共15页
We propose an evolution model of cooperative agent and noncooperative agent aggregates to investigate the dynamic evolution behaviors of the system and the effects of the competing microscopic reactions on the dynamic... We propose an evolution model of cooperative agent and noncooperative agent aggregates to investigate the dynamic evolution behaviors of the system and the effects of the competing microscopic reactions on the dynamic evolution. In this model, each cooperative agent and noncooperative agent are endowed with integer values of cooperative spirits and nonco- operative spirits, respectively. The cooperative spirits of a cooperative agent aggregate and the noncooperative spirits of a noncooperative agent aggregate change via four competing microscopic reaction schemes: the win-win reaction between two cooperative agents, the lose-lose reaction between two noncooperative agents, the win-lose reaction between a coop- erative agent and a noncooperative agent (equivalent to the migration of spirits from cooperative agents to noncooperative agents), and the cooperative agent catalyzed decline of noncooperative spirits. Based on the generalized Smoluchowski's rate equation approach, we investigate the dynamic evolution behaviors such as the total cooperative spirits of all coop- erative agents and the total noncooperative spirits of all noncooperative agents. The effects of the three main groups of competition on the dynamic evolution are revealed. These include: (i) the competition between the lose-lose reaction and the win-lose reaction, which gives rise to respectively the decrease and increase in the noncooperative agent spirits; (ii) the competition between the win-win reaction and the win-lose reaction, which gives rise to respectively the increase and decrease in the cooperative agent spirits; (iii) the competition between the win-lose reaction and the catalyzed-decline reaction, which gives rise to respectively the increase and decrease in the noncooperative agent spirits. 展开更多
关键词 dynamic evolution in competitive societies cooperative and noncooperative agents win-win andlose-lose reaction win-lose reaction
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Time Evolution,Dynamical Quantum Fluctuation and High-Order Squeezing Feature in Polariton System——Ⅰ
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作者 梁国栋 余晓敏 余超凡 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第11期913-924,共12页
We have set up a new reduced model Hamiltonian for the polariton system, in which the nonlinear interaction contains the rotating term k l ( a + b + ab+) and the attractive two-mode squeezed coupling - k2 ( a ... We have set up a new reduced model Hamiltonian for the polariton system, in which the nonlinear interaction contains the rotating term k l ( a + b + ab+) and the attractive two-mode squeezed coupling - k2 ( a + b+ + ab ) . The dynamical evolution of this system has been solved and the nonclassical features relevant to the second-order and high-order squeezing have been obtained in an analytical form. For the first time, in contrast to the existing result, we have confirmed for the phonon field that the attractive two-mode squeezed interaction will not only result in the second-order and high-order squeezing in X-component with the time evolution, but also in time average. Furthermore, the phenomena of collapse and revival of inversion will occur as well in the time evolution of the average number of photon and phonon, as also in the second-order and high-order squeezing of photon field, particularly, in the high-order squeezing of phonon field. 展开更多
关键词 dynamic evolution of polariton system quantum fluctuation high-order squeezing
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Hydrochemical Dynamic Characteristics and Evolution of Underground Brine in the Mahai Salt Lake of the Qaidam Basin Qinghai-Tibet Plateau 被引量:4
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作者 HU Shuya ZHAO Quansheng +2 位作者 WANG Guangcai ZHANG Jianwei FENG Juan 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期1981-1990,共10页
The mineral rock salts present in the Mahai Salt Lake of the Qaidam basin exhibit high solubilities in water. In addition, the multicomponent underground brine exhibits a high salinity and is easily precipitated. In t... The mineral rock salts present in the Mahai Salt Lake of the Qaidam basin exhibit high solubilities in water. In addition, the multicomponent underground brine exhibits a high salinity and is easily precipitated. In the natural state, brine transport in the brine layer is extremely slow, and the brine is in a relatively stable chemical equilibrium state with the rock salt media. However, during mining, both the seepage and the chemical fields fluctuate significantly, thereby disrupting the equilibrium and leading to variations in the chemical composition and dynamic characteristics of the brine. Therefore, we selected underground brine from the Mahai Salt Lake, collecting a total of 183 brine samples over three stages of mining(i.e., the early stage of underground brine extraction, the initial stage of mining, and the later stage of mining). Using a range of analytical techniques, the chemical dynamics of the underground brine water and its evolution were systematically studied. We found that evaporation and enrichment were the main mechanisms of underground brine evolution in the Mahai Salt Lake, with cation exchange and mineral dissolution/precipitation being key factors in determining the dynamic characteristics and evolution of the brine. 展开更多
关键词 Hydrochemical dynamics evolution exploitation process underground brine Mahai Salt Lake Qinghai-Tibet Plateau
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Solving chemical dynamic optimization problems with ranking-based differential evolution algorithms 被引量:3
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作者 Xu Chen Wenli Du Feng Qian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1600-1608,共9页
Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-di... Dynamic optimization problems(DOPs) described by differential equations are often encountered in chemical engineering. Deterministic techniques based on mathematic programming become invalid when the models are non-differentiable or explicit mathematical descriptions do not exist. Recently, evolutionary algorithms are gaining popularity for DOPs as they can be used as robust alternatives when the deterministic techniques are invalid. In this article, a technology named ranking-based mutation operator(RMO) is presented to enhance the previous differential evolution(DE) algorithms to solve DOPs using control vector parameterization. In the RMO, better individuals have higher probabilities to produce offspring, which is helpful for the performance enhancement of DE algorithms. Three DE-RMO algorithms are designed by incorporating the RMO. The three DE-RMO algorithms and their three original DE algorithms are applied to solve four constrained DOPs from the literature. Our simulation results indicate that DE-RMO algorithms exhibit better performance than previous non-ranking DE algorithms and other four evolutionary algorithms. 展开更多
关键词 dynamic optimization Differential evolution Ranking-based mutation operator Control vector parameterization
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The Investigation of the Dynamical Evolution of Extrasolar Three-planetary System GJ 3138
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作者 Alexander Perminov Eduard Kuznetsov 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2022年第1期68-84,共17页
This article is devoted to studying the dynamical evolution and orbital stability of compact extrasolar threeplanetary system GJ 3138. In this system, all semimajor axes are less than 0.7 au. The modeling of planetary... This article is devoted to studying the dynamical evolution and orbital stability of compact extrasolar threeplanetary system GJ 3138. In this system, all semimajor axes are less than 0.7 au. The modeling of planetary motion is performed using the averaged semi-analytical motion theory of the second order in planetary masses,which the authors construct. Unknown and known with errors orbital elements vary in allowable limits to obtain a set of initial conditions. Each of these initial conditions is applied for the modeling of planetary motion. The assumption about the stability of observed planetary systems allows to eliminate the initial conditions leading to excessive growth of the orbital eccentricities and inclinations and to identify those under which these orbital elements conserve moderate values over the whole modeling interval. Thus, it becomes possible to limit the range of possible values of unknown orbital elements and determine their most probable values in terms of stability. 展开更多
关键词 Planetary Systems planets and satellites:dynamical evolution and stability planetstar interactions celestial mechanics
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Dynamical Evolution of an Effective Two-Level System with PT Symmetry
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作者 Lei Du Zhihao Xu +1 位作者 Chuanhao Yin Liping Guo 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期10-14,共5页
We investigate the dynamics of parity-and time-reversal(PT) symmetric two-energy-level atoms in the presence of two optical and one radio-frequency fields. The strength and relative phase of fields can drive the sys... We investigate the dynamics of parity-and time-reversal(PT) symmetric two-energy-level atoms in the presence of two optical and one radio-frequency fields. The strength and relative phase of fields can drive the system from the unbroken to the broken PT symmetric regions. Compared with the Hermitian model, Rabi-type oscillation is still observed, and the oscillation characteristics are also adjusted by the strength and relative phase in the region of the unbroken symmetry. At the exception point, the oscillation breaks down. To better understand the underlying properties we study the effective Bloch dynamics and find that the emergence of the PT components of the fixed points is the feature of the PT symmetry breaking and the projections in the x–y plane can be controlled with high flexibility compared with the standard two-level system with the PT symmetry. It helps to study the dynamic behavior of the complex PT symmetric model. 展开更多
关键词 PT dynamical evolution of an Effective Two-Level System with PT Symmetry
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Transformation power or development pressure:economic growth targets and urban carbon productivity
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作者 Longtao Chen Yi Zheng +1 位作者 Xianfeng Han Juan Liu 《Chinese Journal of Population,Resources and Environment》 2024年第2期176-184,共9页
Maintaining moderate economic growth targets(EGTs)is the key for local governments to effectively implement the“carbon peak and carbon neutrality”goals under the refreshed development pattern.Utilizing panel data of... Maintaining moderate economic growth targets(EGTs)is the key for local governments to effectively implement the“carbon peak and carbon neutrality”goals under the refreshed development pattern.Utilizing panel data of 276 prefecture-level cities in China's Mainland from 2010 to 2020,and employing methods such as intermediary and threshold models,this study empirically analyzes the internal mechanism of EGT’s impact on urban carbon productivity(UCP).Our findings demonstrate that:①The overall EGT during the analyzed period is not conducive to improving UCP.This conclusion remains valid after a series of robustness tests.This effect is more pronounced in the central region and resource-based cities than in the east-west region and non resource-based cities.②EGT not only directly suppresses UCP but also exerts indirect negative impacts on UCP from three aspects:delaying the digital economy(DE),constraining financial expansion(FE),and hindering green technology innovation(GTI).This negative indirect effect is similar to or even surpasses the direct effect,suggesting that the internal relationship between EGT and“dual-carbon”goals should be re-evaluated from a new compound perspective.③EGT not only has a simple linear impact on UCP but also significantly exhibits a dynamic evolution pattern in inverted“U”shape.That is,as EGT continuously upgrades,a nonlinear impact on UCP emerges in the form of“promoting first,suppressing later”.This indicates that surpassing the“degree”limit for EGT will be detrimental to the improvement of UCP.This study broadens the scope of carbon productivity analysis by introducing a new perspective centered on EGT.The insights gleaned from this research offer valuable guidance for local governments to effectively manage economic growth expectations and promote the synchronized achievement of dual-carbon objectives. 展开更多
关键词 Economic growth target Urban carbon productivity Mediating effects dynamic evolution
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Capture Efficiency Analysis in the Circular Restricted Three-body Problem
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作者 Yu-Xuan Miao Xi-Yun Hou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期198-210,共13页
Temporary capture efficiency is studied in the framework of the circular restricted three-body problem in two steps.First, a non-uniform distribution of test particles around the secondary's orbit is obtained by f... Temporary capture efficiency is studied in the framework of the circular restricted three-body problem in two steps.First, a non-uniform distribution of test particles around the secondary's orbit is obtained by fully accounting the secondary's gravitational influence. Second, the capture efficiency is computed based on the non-uniform distribution. Several factors influencing the result are discussed. By studying the capture efficiency in the circular restricted three-body problem of different mass ratios, a power-law relation between the capture efficiency(p) and the mass ratio(μ) is established, which is given by p ≈ 0.27 × μ^(0.53), within the range of 3.0035 ×10^(-6)≤ μ ≤ 3.0034 × 10^(-5). Taking the Sun–Earth system as an example, the influence from the orbit eccentricity of the secondary on the non-uniform distribution and the capture efficiency is studied. Our studies find that the secondary's orbit eccentricity has a negative influence on the capture efficiency. 展开更多
关键词 METHODS numerical-celestial mechanics-planets and satellites dynamical evolution and stability
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