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Complexity Behind Simplicity——An analysis of Langston Hughes' Art of Writing in "Early Autumn"
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作者 余丽 《海外英语》 2012年第4X期9-10,共2页
Love is an eternal subject with many references in many novels,but Langston Hughes approaches it in a most simplified manner to portray the complex feeling of the protagonists.He achieves this inward complexity throug... Love is an eternal subject with many references in many novels,but Langston Hughes approaches it in a most simplified manner to portray the complex feeling of the protagonists.He achieves this inward complexity through carefully-treated outward simplicity.The paper discusses this art of writing in Early Autumn from such aspects as the dramatic point of view,well-designed setting,careful presentation and effective rhetorical devices. 展开更多
关键词 complexity simplicity RHETORICAL DEVICES
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COMPLEXITY OF EVOLUTION LANGUAGES OF THE ELEMENTARY CELLULAR AUTOMATON OF RULE 146 被引量:1
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作者 Wang Yi Morita Kenichi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期418-428,共11页
Symbolic dynamics of cellular automata is introduced by coarse-graining the temporal evolution orbits. Evolution languages are defined. By using the theory of formal languages and automata, the complexity of evolution... Symbolic dynamics of cellular automata is introduced by coarse-graining the temporal evolution orbits. Evolution languages are defined. By using the theory of formal languages and automata, the complexity of evolution languages of the elementary cellular automaton of rule 146 is studied and it is proved that its width 1-evolution language is regular, but for every n ≥ 2 its width n-evolution language is not context-free but context-sensitive. Also, the same results hold for the equivalent (under conjugation) elementary cellular automaton of rule 182. 展开更多
关键词 complexity cellular automaton evolution language formal language.
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Biological Evolution: Entropy, Complexity and Stability 被引量:1
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作者 C.G Chakrabarti Koyel Ghosh 《Journal of Modern Physics》 2011年第6期621-626,共6页
In the present paper we have made an attempt to investigate the importance of the concepts of dynamical stability and complexity along with their interelationship in an evolving biological systems described by a syste... In the present paper we have made an attempt to investigate the importance of the concepts of dynamical stability and complexity along with their interelationship in an evolving biological systems described by a system of kinetic (both deterministic and chaotic) equations. The key to the investigation lies in the expres-sion of a time-dependent Boltzmann-like entropy function derived from the dynamical model of the system. A significant result is the determination of the expression of Boltzmann - entropy production rate of the evolving system leading to the well-known Pesin-type identity which provides an elegant and simple meas-ure of dynamical complexity in terms of positive Lyapunov exponents. The expression of dynamical com-plexity has been found to be very suitable in the study of the increase of dynamical complexity with the suc-cessive instabilities resulting from the appearance of new polymer species (or ecological species) into the original system. The increase of the dynamical complexity with the evolutionary process has been explained with a simple competitive model system leading to the “principle of natural selection”. 展开更多
关键词 Boltzmann-Entropy DYNAMICAL STABILITY Pesin-type Identity and DYNAMICAL complexity Lyapunov EXPONENTS Structural Instabilities Biological evolution
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Temporal and spatial evolution of global major grain trade patterns
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作者 Ziqi Yin Jiaxuan Hu +3 位作者 Jing Zhang Xiangyang Zhou Lingling Li Jianzhai Wu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期1075-1086,共12页
The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain ... The complex and volatile international landscape has significantly impacted global grain supply security. This study uses a complex network analysis model to examine the evolution and trends of the global major grain trade from 1990 to 2020, focusing on network topology, centrality ranking, and community structure. There are three major findings. First, the global major grain trade network has expanded in scale, with a growing emphasis on diversification and balance. During the study period, the United States, Canada, China, and Brazil were the core nodes of the network. Grain-exporting countries were mainly situated in Asia, the Americas, and Europe, and importing countries in Asia, Africa, and Europe. Second, a significant increase in the number of high centrality countries with high export capacity occurred, benefiting from natural advantages such as fertile land and favorable climates. Third, the main global grain trade network is divided into four communities, with the Americas-Europe community being the largest and most widespread. The formation of the community pattern was influenced by geographic proximity, driven by the core exporting countries. Therefore, the world needs to enhance the existing trade model, promote the multi-polarization of the grain trade network, and establish a global vision for the future community. Countries and regions should participate actively in global grain trade security governance and institutional reform, expand trade links with other countries, and optimize import and export policies to reduce trade risks. 展开更多
关键词 grain trade pattern evolution complex network
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Exploring Biocomplexity in Cancer: A Comprehensive Review
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作者 Andras Szasz Gyula Peter Szigeti 《Open Journal of Biophysics》 2024年第2期154-238,共85页
Living objects have complex internal and external interactions. The complexity is regulated and controlled by homeostasis, which is the balance of multiple opposing influences. The environmental effects finally guide ... Living objects have complex internal and external interactions. The complexity is regulated and controlled by homeostasis, which is the balance of multiple opposing influences. The environmental effects finally guide the self-organized structure. The living systems are open, dynamic structures performing random, stationary, stochastic, self-organizing processes. The self-organizing procedure is defined by the spatial-temporal fractal structure, which is self-similar both in space and time. The system’s complexity appears in its energetics, which tries the most efficient use of the available energies;for that, it organizes various well-connected networks. The controller of environmental relations is the Darwinian selection on a long-time scale. The energetics optimize the healthy processes tuned to the highest efficacy and minimal loss (minimalization of the entropy production). The organism is built up by morphogenetic rules and develops various networks from the genetic level to the organism. The networks have intensive crosstalk and form a balance in the Nash equilibrium, which is the homeostatic state in healthy conditions. Homeostasis may be described as a Nash equilibrium, which ensures energy distribution in a “democratic” way regarding the functions of the parts in the complete system. Cancer radically changes the network system in the organism. Cancer is a network disease. Deviation from healthy networking appears at every level, from genetic (molecular) to cells, tissues, organs, and organisms. The strong proliferation of malignant tissue is the origin of most of the life-threatening processes. The weak side of cancer development is the change of complex information networking in the system, being vulnerable to immune attacks. Cancer cells are masters of adaptation and evade immune surveillance. This hiding process can be broken by electromagnetic nonionizing radiation, for which the malignant structure has no adaptation strategy. Our objective is to review the different sides of living complexity and use the knowledge to fight against cancer. 展开更多
关键词 complexity Networks SMALL-WORLD Genetic Mutations SELF-ORGANIZING Self-Symmetry Energetic Balance Entropy Nash Equilibrium GAMES evolution CANCER Therapy
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Probability Distribution of China Aviation Network Average Degree of Edge Vertices and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Liang Yanping 《Journal of Traffic and Transportation Engineering》 2024年第2期51-62,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of average degree of edge vertices of China aviation network w... In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of average degree of edge vertices of China aviation network were studied based on the statistics data of China civil aviation network in 1988, 1994, 2001, 2008 and 2015. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network. Based on the statistical data, the average degrees of edge vertices in China aviation network in 1988, 1994, 2001, 2008 and 2015 were calculated. Using the probability statistical analysis method and regression analysis approach, it was found that the average degree of edge vertices had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network average degree of edge vertices normal distribution linear evolution trace
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Probability Distribution of Ratio of China Aviation Network Edge Vertices Degree and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Wei Liying 《Journal of Traffic and Transportation Engineering》 2024年第3期119-129,共11页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of ratio of China aviation network edge vertices degree were s... In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of ratio of China aviation network edge vertices degree were studied based on the statistics data of China civil aviation network in 1988, 1994, 2001, 2008 and 2015. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network. Based on the statistical data, the ratio of edge vertices degree in China aviation network in 1988, 1994, 2001, 2008 and 2015 were calculated. Using the probability statistical analysis method and regression analysis approach, it was found that the ratio of edge vertices degree had linear probability distribution and the two parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network ratio of edge vertices degree linear probability distribution linear evolution trace.
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Probability Distribution of Arithmetic Average of China Aviation Network Edge Vertices Nearest Neighbor Average Degree Value and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Xiong Zhihua 《Journal of Traffic and Transportation Engineering》 2024年第4期163-174,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average... In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of arithmetic average of edge vertices nearest neighbor average degree values of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the arithmetic averages of edge vertices nearest neighbor average degree values of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the arithmetic average of edge vertices nearest neighbor average degree values had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network arithmetic average of edge vertices nearest neighbor average degree value linear evolution trace
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Effect of conformity on evolution of cooperation in a coordination game
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作者 王先甲 王饕 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期172-183,共12页
Individual decision-making processes are not solely driven by self-interest maximization but are also influenced by the pressure to conform to the group.In primary games like the prisoner's dilemma,the presence of... Individual decision-making processes are not solely driven by self-interest maximization but are also influenced by the pressure to conform to the group.In primary games like the prisoner's dilemma,the presence of conformity pressure may facilitate the constructive development of cooperative behavior.In this study,we investigate how conformity influences the growth of cooperation in complicated coordination games.Our findings reveal that,even in the presence of stringent game rules,conformity can promote cooperation.In fact,a certain level of conformity pressure can even eliminate the“defection basin”of deer hunting games played on regular networks.Additionally,we demonstrate that the effect of conformity on cooperative behavior is contingent upon the degree of conformity pressure,with different levels of conformity pressure producing opposite effects.These findings provide novel insights into the promotion of cooperative evolution.For instance,if increasing the reward for cooperation has proven ineffective,manipulating the proportion of initial strategy choices may be a more promising approach. 展开更多
关键词 cooperative evolution complex network conformity behavior spatial dynamics
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Probability Distribution of China Aviation Network Nearest Neighbor Average Degree and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2023年第3期95-106,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of node nearest neighbor average degree of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the probability distribution and evolution trace of node nearest neighbor average degree of China aviation network were studied based on the statistics data of China civil aviation network in 1988,1994,2001,2008 and 2015.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network.Based on the statistical data,the nearest neighbor average degrees of nodes in China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Using the probability statistical analysis method,it was found that the nearest neighbor average degree had the probability distribution of normal function and the position parameters and scale parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network nearest neighbor average degree normal probability distribution linear evolution trace
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A New Model on Origin and Evolution of Biology 被引量:1
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作者 王奕蛟 冯綮一 柴立和 《Agricultural Science & Technology》 CAS 2009年第4期4-7,共4页
Modified classical Boltzmann entropy as generalized entropy, then proposed Maximum Generalized Entropy Principle fusing physics and biology, and established a new model for biological origin and evolutions based on th... Modified classical Boltzmann entropy as generalized entropy, then proposed Maximum Generalized Entropy Principle fusing physics and biology, and established a new model for biological origin and evolutions based on this principle, finally took protein evolution for an example to analyze. The model provided some reference for biological complexity research. 展开更多
关键词 Biological origin and evolution complexity Generalized entropy
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Nearest Neighbor Average Degree of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Chunyue Zhang Xiaoxuan 《Journal of Traffic and Transportation Engineering》 2023年第4期159-171,共13页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of Chi... In order to reveal the complex network characteristics and evolution principle of China aviation network, the relationship between the node degree and the nearest neighbor average degree and its evolution trace of China aviation network in 1988, 1994, 2001, 2008 and 2015 were studied. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network. According to the statistical data, the node nearest neighbor average degree of China aviation network in 1988, 1994, 2001, 2008 and 2015 was calculated. Through regression analysis, it was found that the node degree had a negative exponential relationship with the nearest neighbor average degree, and the two parameters of the negative exponential relationship had linear evolution trace. 展开更多
关键词 China aviation network complex network node degree nearest neighbor average degree negative exponential relationship evolution trace.
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COMPLEXITY AND CHAOTIC DYNAMICS OF ROCK FAULTING 被引量:1
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作者 TANKaixuan XIEYanshi +1 位作者 CHENGuanghao HUANGXiaonai 《Geotectonica et Metallogenia》 2003年第1期104-111,共8页
Fault is a complex dynamic system controlled by the coupling of rock texture, reaction, fluid flow,stress, and rock deformation mechanism. A coupled reaction-transport- mechanical dynamic model for fault system is est... Fault is a complex dynamic system controlled by the coupling of rock texture, reaction, fluid flow,stress, and rock deformation mechanism. A coupled reaction-transport- mechanical dynamic model for fault system is established and described in this paper. An example is presented for the Shuikoushan deposit, Hunan. The results of dynamic simulation indicate that the evolution and magnitude of fracture permeability of different rocks are different, and that faulting can enhance the spatial heterogeneity of rock permeability and facilitate fluid flow and mineralization in local fault zone. The pressure for a fault usually shows a variation mode of aperiodic oscillation with time, which reflects the chaotic behavior of the evolution of a fault. 展开更多
关键词 reaction-transport-mechanical coupling complexity chaotic evolution rock faulting
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NUMERICAL STUDIES FOR A MODEL DESCRIBING COMPLEXITY
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作者 黄欣 刘曾荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第8期767-770,共4页
A simple model based on the discussion for infinite dimensional system is introduced to investigate the dynamical complexity for continous system.By using numerical. methods,we show the dynamical behaviors of the maod... A simple model based on the discussion for infinite dimensional system is introduced to investigate the dynamical complexity for continous system.By using numerical. methods,we show the dynamical behaviors of the maodel model appear tocorrespond to universal language and context-senitive language. 展开更多
关键词 complexity. evolution of pattern numerical method
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The Spatiotemporal Evolution of Wave Packets under Chaotic Condition
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作者 LIUFang XUGong-Ou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第5期531-538,共8页
Using the minimum uncertainty state of quantum integrable system as initial state, the spatiotemporal evolution of the wave packet under the action of perturbed Hamiltonian is studied causally as in classical mechani... Using the minimum uncertainty state of quantum integrable system as initial state, the spatiotemporal evolution of the wave packet under the action of perturbed Hamiltonian is studied causally as in classical mechanics. Due to the existence of the avoided energy level crossing in the spectrum there exist nonlinear resonances between some pairs of neighboring components of the wave packet, the deterministic dynamical evolution becomes very complicated and appears to be chaotic. It is proposed to use expectation values for the whole set of basic dynamical variables and the corresponding spreading widths to describe the topological features concisely such that the quantum chaotic motion can be studied in contrast with the quantum regular motion and well characterized with the asymptotic behaviors. It has been demonstrated with numerical results that such a wave packet has indeed quantum behaviors of ergodicity as in corresponding classical case. 展开更多
关键词 complexity in spatiotemporal evolution concise topological description quantum behaviors of ergodicity
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Shuffled complex evolution coupled with stochastic ranking for reservoir scheduling problems 被引量:3
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作者 Jing-qiao Mao Ming-ming Tian +3 位作者 Teng-fei Hu Kang Ji Ling-quan Dai Hui-chao Dai 《Water Science and Engineering》 EI CAS CSCD 2019年第4期307-318,共12页
This paper introduces an optimization method(SCE-SR)that combines shuffled complex evolution(SCE)and stochastic ranking(SR)to solve constrained reservoir scheduling problems,ranking individuals with both objectives an... This paper introduces an optimization method(SCE-SR)that combines shuffled complex evolution(SCE)and stochastic ranking(SR)to solve constrained reservoir scheduling problems,ranking individuals with both objectives and constrains considered.A specialized strategy is used in the evolution process to ensure that the optimal results are feasible individuals.This method is suitable for handling multiple conflicting constraints,and is easy to implement,requiring little parameter tuning.The search properties of the method are ensured through the combination of deterministic and probabilistic approaches.The proposed SCE-SR was tested against hydropower scheduling problems of a single reservoir and a multi-reservoir system,and its performance is compared with that of two classical methods(the dynamic programming and genetic algorithm).The results show that the SCE-SR method is an effective and efficient method for optimizing hydropower generation and locating feasible regions quickly,with sufficient global convergence properties and robustness.The operation schedules obtained satisfy the basic scheduling requirements of reservoirs. 展开更多
关键词 Reservoir scheduling Optimization method Constraint handling Shuffled complex evolution Stochastic ranking
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Metamorphism of the northern Liaoning Complex:Implications for the tectonic evolution of Neoarchean basement of the Eastern Block,North China Craton 被引量:14
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作者 Kam Kuen Wu Guochun Zhao +3 位作者 Min Sun Changqing Yin Yanhong He Pui Yuk Tam 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期305-320,共16页
As one of the areas where typical late Archean crust is exposed in the Eastern Block of the North China Craton, the northern Laioning Complex consists principally of tonalitic-trondhjemitic-granodioritic (TTG) gneis... As one of the areas where typical late Archean crust is exposed in the Eastern Block of the North China Craton, the northern Laioning Complex consists principally of tonalitic-trondhjemitic-granodioritic (TTG) gneisses, massive granitoids and supracrustal rocks. The supracrustal rocks, named the Qingyuan Group, consist of interbedded amphibolite, hornblende granulite, biotite granulite and BIF. Petrological evidence indicates that the amphibolites experienced the early prograde (M1), peak (M2) and post-peak (M3) metamorphism. The early prograde assemblage (M1) is preserved as mineral inclusions, represented by actinotite + hornblende - plagioclase + epidote + quartz 4- sphene, within garnet porphyroblasts. The peak assemblage (M2) is indicated by garnet + clinopyroxene + hornblende + plagioclase + quartz + ilmenite, which occur as major mineral phases in the rock. The post-peak assemblage (M3) is characterized by the garnet 4- quartz symplectite. The P-T pseudosections in the NCFMASHTO system constructed by using THERMOCALC define the P-T conditions of M1, M2 and M3 at 490-550 C+(4.5 kbar, 780 810 C/7.65- 8.40 kbar and 630-670 +C]8.15-9.40 kbar, respectively. As a result, an anticlockwise P-T path involving isobaric cooling is inferred for the metamorphic evolution of the amphibolites. Such a P-T path suggests that the late Archean metamorphism of the northern Liaoning Complex was related to the intrusion and underplating of mantle-derived magmas. The underplating of voluminous mantle-derived magmas leading to metamorphism with an anticlockwise P-T path involving isobaric cooling may have occurred in continental magmatic arc regions, above hot spots driven by mantle plumes, or in continental rift envi- ronments. A mantle plume model is favored because this model can reasonably interpret many other geological features of late Archean basement rocks from the northern Liaoning Complex in the Eastern Block of the North China Craton as well as their anticlockwise P-T paths involving isobaric cooling. 展开更多
关键词 Amphibolites Northern Liaoning complex North China Craton Late Archean Metamorphic evolution
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Spatiotemporal Evolution of Ecological Security in the Wanjiang City Belt,China 被引量:6
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作者 CAO Yuhong LIU Meiyun +2 位作者 ZHANG Yu CHEN Chen CAO Weidong 《Chinese Geographical Science》 SCIE CSCD 2020年第6期1052-1064,共13页
Ecological security is the foundation and guarantee of sustainable development,and its importance is increasingly widely recognized and valued by the world.The Yangtze River Basin is an important ecological security b... Ecological security is the foundation and guarantee of sustainable development,and its importance is increasingly widely recognized and valued by the world.The Yangtze River Basin is an important ecological security barrier in China and the Wanjiang City Belt(WCB)along the Yangtze River is directly related to the ecological security pattern of the entire basin.Based on the Driver-Pressure-State-Impact-Response(DPSIR)model and a geographical information system(GIS)platform,an ecosystem security evaluation index system was constructed to measure and evaluate the evolution of ecosystem security in the WCB,China.Results showed that:1)From 2000 to 2018,the overall level of ecological security in the study area was in a state of either early warning or medium warning,but the level of ecological security in each prefecture-level city was significantly different.2)From the perspective of the evolution of the ecosystem,the value of its comprehensive evaluation index dropped from 4.255 in 2000 to 3.885 in 2018.From the perspective of subsystems,the value of Pressure comprehensive evaluation index is much higher than that of other subsystems,indicating that during the rapid development of the social economy,the pressure on the natural environment tended to rise,and triggered changes in the State and Response subsystems.3)The coefficient of variation(CV)of the Driver was much higher than other factors influencing the ecological security system.There are large differences in the economic development and ecological evolution of the cities in the WCB.This study has improved the theoretical research on regional ecological security,and has certain practical guiding significance for building a beautiful,green and sustainable China and promoting global ecological security. 展开更多
关键词 ecological security complex ecosystem spatiotemporal evolution spatial difference Wanjiang City Belt(WCB)
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O-O bond formation mechanisms during the oxygen evolution reaction over synthetic molecular catalysts 被引量:4
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作者 Xue-Peng Zhang Hong-Yan Wang +2 位作者 Haoquan Zheng Wei Zhang Rui Cao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第8期1253-1268,共16页
Water oxidation is one of the most important reactions in natural and artificial energy conversion schemes.In nature,solar energy is converted to chemical energy via water oxidation at the oxygen-evolving center of ph... Water oxidation is one of the most important reactions in natural and artificial energy conversion schemes.In nature,solar energy is converted to chemical energy via water oxidation at the oxygen-evolving center of photosystem II to generate dioxygen,protons,and electrons.In artificial energy schemes,water oxidation is one of the half reactions of water splitting,which is an appealing strategy for energy conversion via photocatalytic,electrocatalytic,or photoelectrocatalytic processes.Because it is thermodynamically unfavorable and kinetically slow,water oxidation is the bottleneck for achieving large-scale water splitting.Thus,developing highly efficient water oxidation catalysts has attracted the interests of researchers in the past decades.The formation of O-O bonds is typically the rate-determining step of the water oxidation catalytic cycle.Therefore,better understanding this key step is critical for the rational design of more efficient catalysts.This review focuses on elucidating the evolution of metal-oxygen species during transition metal-catalyzed water oxidation,and more importantly,on discussing the feasible O-O bond formation mechanisms during the oxygen evolution reaction over synthetic molecular catalysts. 展开更多
关键词 Oxygen evolution reaction Water oxidation O-O bond formation Transition metal complex Molecular electrocatalysis Reaction mechanism
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The evolution of complex brains and behaviors in African cichlid fishes 被引量:1
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作者 Caroly A.SHUMWAY 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第1期144-156,共13页
In this review, I explore the effects of both social organization and the physical environment, specifically habitat complexity, on the brains and behavior of highly visual African cichlid fishes, drawing on examples ... In this review, I explore the effects of both social organization and the physical environment, specifically habitat complexity, on the brains and behavior of highly visual African cichlid fishes, drawing on examples from primates and birds where appropriate. In closely related fishes from the monophyletic Ectodinii clade of Lake Tanganyika, both forces influence cichlid brains and behavior. Considering social influences first, visual acuity differs with respect to social organization (monogamy versus polygyny). Both the telencephalon and amygdalar homologue, area Dm, are larger in monogamous species. Monogamous species are found to have more vasotocin-immunoreactive cells in the preoptic area of the brain. Habitat complexity also influences brain and behavior in these fishes. Total brain size, telencephalic and cerebellar size are positively correlated with habitat complexity. Visual acuity and spatial memory are enhanced in cichlids living in more complex environments. However habitat complexity and social forces affect cichlid brains differently. Taken together, our field data and plasticity data suggest that some of the species-specific neural effects of habitat complexity could be the consequence of the corresponding social correlates. Environmental forces, however, exert a broader effect on brain structures than social ones do, suggesting allometric expansion of the brain structures in concert with brain size and/or co-evolntion of these structures [Current Zoology 56 (1): 144-156, 2010]. 展开更多
关键词 FISH evolution BRAIN Behavior Social organization Habitat complexity
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