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地震地下流体物理化学动态形成的基础理论问题 被引量:7
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作者 车用太 鱼金子 赵苹 《国际地震动态》 1995年第12期6-10,共5页
本文以80年代国内外学者在地下流体的流体动力学、热动力学与化学动力学领域的探索中所取得的理论成果为基础,针对地震地下流体的压力、温度与化学组分动态观测与研究现状,从理论上阐述了地下流体物理化学各项动态形成的机制及其内... 本文以80年代国内外学者在地下流体的流体动力学、热动力学与化学动力学领域的探索中所取得的理论成果为基础,针对地震地下流体的压力、温度与化学组分动态观测与研究现状,从理论上阐述了地下流体物理化学各项动态形成的机制及其内在联系,以促进我国地震地下流体动态的基础理论研究。 展开更多
关键词 地下流体 理化动态 形成机制 地震预报
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三峡库区香溪河支流放流滤食性鱼类后理化特征的比较研究
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作者 蔡煜 梁莉甜 +6 位作者 蔡焰值 雷晓中 汪亮 刘志国 卢涛 姚云龙 秦晓燕 《湖北农业科学》 北大核心 2013年第13期3089-3094,共6页
从2010年4月至2012年12月对香溪河支流7批次放流滤食性鱼类苗种1 468万尾,对放流前与放流后的水域理化因子特征进行常规监测。结果显示,放流滤食性鱼种后总氮(TN)、氨氮(NH4-N)、亚硝酸盐氮(NO2-N)、硝酸盐氮(NO3-N)、总磷(TP)、正磷酸... 从2010年4月至2012年12月对香溪河支流7批次放流滤食性鱼类苗种1 468万尾,对放流前与放流后的水域理化因子特征进行常规监测。结果显示,放流滤食性鱼种后总氮(TN)、氨氮(NH4-N)、亚硝酸盐氮(NO2-N)、硝酸盐氮(NO3-N)、总磷(TP)、正磷酸盐磷(PO4-P)、化学耗氧量(COD)、叶绿素a要明显低于放流前,投放苗种前平均值分别为3.10 mg/L、0.421 mg/L、0.048 mg/L、2.869 mg/L、0.549 mg/L、0.299 mg/L、16.563 mg/L、26.447 mg/m3;放流鱼种后平均值分别为2.20 mg/L、0.065 mg/L、0.022 mg/L、1.643 mg/L、0.495 mg/L、0.155 mg/L、10.465 mg/L、6.608 mg/m3。放流前支流营养化TLI为67.0、放流后为56.4,香溪河支流水域呈轻度富营养化(TLI>53)。为生态修复调控水华发生建议香溪河支流水域每年放流滤食性鱼类苗种。 展开更多
关键词 香溪河支流 滤食性鱼类 增殖放流 理化动态 水华调控.
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Enhanced Oxygen Evolution Reaction Performance by Dynamic Adsorption of Intermediates on C2N-Supported Single Atom Catalysts
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作者 Chongchong Li Li Sheng +1 位作者 Yanan Zhou Wenhua Zhang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第5期662-670,I0078-I0093,I0100,I0101,共27页
The dynamic adsorption of possible intermediates on single-atom catalysts(SACs)under working condition plays a key role in the electrocatalytic performance by the oxygen evolution reaction(OER),and therefore the perfo... The dynamic adsorption of possible intermediates on single-atom catalysts(SACs)under working condition plays a key role in the electrocatalytic performance by the oxygen evolution reaction(OER),and therefore the performance of the dynamic adsorption should be fully considered in the theoretical screening of potential SACs.Based on density functional theory calculations,the OER performance of 27 types of C_(2)N-supported single transition metal atoms(TM@C_(2)N)is systematically investigated without and with considering the dynamic adsorption of possible intermediates.Without considering dynamic adsorption,only Rh@C_(2)N and Ni@C_(2)N are screened out as good catalysts.However,by further considering the dynamic adsorption configurations of possible intermediates,more promising TM@C_(2)N SACs including Fe(Co,Ni,Ru,Rh,Ir)@C_(2)N toward the OER are screened out.The presence of the intermediates(*HO,*O)on SACs could shift their d band center toward lower energy level,which makes the interaction between the adsorbate and SACs moderate and thus enhances their OER performance.The present work is instructive for further screening and designing of efficient single-atom catalysts for the oxygen evolution reaction. 展开更多
关键词 Density functional theory Single-atom catalyst Oxygen evolution reaction Dynamic adsorption
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Rocky Desertification Dynamic Analysis and the Development of Management Information System 被引量:12
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作者 颜学莉 谢世友 《Agricultural Science & Technology》 CAS 2008年第2期45-48,92,共5页
With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was... With the background of severe rocky desertification in the west of China and the ohjective of ecological environment construction and poverty elimination, the management information system of rocky desertification was designed according to the natural and humane characteristics in Nanchuan of Sichuan Province. The system was composed of data management module, information query module for rocky desertification, spatial analysis module and dynamic monitoring module. 展开更多
关键词 Rocky desertification Inforumtion system Dynamic analysis Nanchuan
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Design and Research on Artificial Rumen Continuous Culture System
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作者 孟宪章 李敏 +2 位作者 施继红 胡晓丽 刘庆福 《Agricultural Science & Technology》 CAS 2012年第11期2445-2448,共4页
[Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the... [Objective] The paper was to study the dynamic changes of forage nutrient substance fermentation in rumen, and a set of continuous culture system of artificial rumen was designed. [Method] With in vivo as control, the simulating rumen fer- mentation effect in vitro culture system was evaluated. [Result] The simulation rumen fermentation test needed adaptive phase of 2-3 d, and the fermentation state was relatively stable within 3-9 d, with good effects. The test showed certain regularity variation with index value of rumen in vivo. [Conclusion] The continuous culture sys- tem of artificial rumen could be used as the ideal model to study the rumen fermen- tation in vivo. 展开更多
关键词 Rumen fermentation Continuous culture system Experimental research Effect evaluation
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Damping of Magnetorheological Elastomers 被引量:2
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作者 Lin Chen Xing-long Gong Wei-hua Li 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第6期581-585,共5页
The damping property of magnetorheological (MR) elastomers is characterized by a modified dynamic mechanical-magnetic coupled analyzer. The influences of the external magnetic flux density, damping of the matrix, co... The damping property of magnetorheological (MR) elastomers is characterized by a modified dynamic mechanical-magnetic coupled analyzer. The influences of the external magnetic flux density, damping of the matrix, content of iron particles, dynamic strain, and driving frequency on the damping properties of MR elastomers were investigated experimentally. The experimental results indicate that the damping properties of MR elastomers greatly depend on the interfacial slipping between the inner particles and the matrix. Different from general composite materials, the interracial slipping in MR elastomers is affected by the external applied magnetic field. 展开更多
关键词 Magnetorheological elastomers Damping property Interfacial slipping
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Environmental Factors Affecting Temporal and Spatial Dynamics of Soil Erosion in Xingguo County, South China 被引量:12
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作者 WANG Ku SHI Xue-Zheng +5 位作者 YU Dong-Sheng SHI De-Ming CHEN Jing-Ming XU Bin-Bin LIANG Yin LI De-Cheng 《Pedosphere》 SCIE CAS CSCD 2005年第5期620-627,共8页
By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination withthe remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in... By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination withthe remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South Chinawere analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The resultsshowed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land undersevere erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were moresusceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. Theseareas deserve special attention in monitoring and controlling. 展开更多
关键词 GIS remote sensing soil erosion South China Xingguo County
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Ultrastructure of spermatozoa of Bullacta exarata (philippi) and its significance on reproductive evolution and physio-ecological adaptation 被引量:3
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作者 应雪萍 杨万喜 +1 位作者 姜乃澄 张永普 《Journal of Zhejiang University Science》 EI CSCD 2004年第10期1211-1217,共7页
The morphology and ultrastructure of Bullacta exarata spermatozoa observed by light and transmission electron microscopy are presented in this paper. The spermatozoon is composed of head with a simple acrosomal comple... The morphology and ultrastructure of Bullacta exarata spermatozoa observed by light and transmission electron microscopy are presented in this paper. The spermatozoon is composed of head with a simple acrosomal complex and an elongated nucleus, and tail with a midpiece, principal piece and an end piece. The midpiece consists of a mitochondrial ring, and the principal piece is composed of axoneme and lateral fin. The structure of 5. exarata spermatozoa differs significantly from that of other gastropods, especially in the lateral fin and the principal piece, which was described scarcely before. A comparison is made between B. exarata and other gastropods, and its significance on reproductive evolution and physio-ecological adaptation is preliminarily discussed. 展开更多
关键词 Bullacta exarata SPERMATOZOON ULTRASTRUCTURE EVOLUTION Physio-ecological adaptation
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Analysis of Nida's dynamic equivalence from the perspective of domestication and foreignization 被引量:1
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作者 YU Yuan LI Wan-jun 《Sino-US English Teaching》 2007年第9期74-81,共8页
This paper presents an introduction to the concepts of domestication and foreignization and the theory of Nida's "dynamic equivalence". Then, the paper makes an analysis of "dynamic equivalence" from the perspect... This paper presents an introduction to the concepts of domestication and foreignization and the theory of Nida's "dynamic equivalence". Then, the paper makes an analysis of "dynamic equivalence" from the perspective of domestication and foreignization. 展开更多
关键词 DOMESTICATION FOREIGNIZATION dynamic equivalence
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Dynamic Visualization Approach of the Multiphase Flow Using Electrical Capacitance Tomography 被引量:1
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作者 王泽璞 陈琪 +2 位作者 王雪瑶 李志宏 韩振兴 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期380-388,共9页
Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualiza... Identifying the flow patterns is vital for understanding the complicated physical mechanisms in multiphase flows.For this purpose,electrical capacitance tomography(ECT) technique is considered as a promising visualization method for the flow pattern identification,in which image reconstruction algorithms play an important role.In this paper,a generalized dynamic reconstruction model,which integrates ECT measurement information and physical evolution information of the objects of interest,was presented.A generalized objective functional that simultaneously considers the spatial constraints,temporal constraints and dynamic evolution information of the objects of interest was proposed.Numerical simulations and experiments were implemented to evaluate the feasibility and efficiency of the proposed algorithm.For the cases considered in this paper,the proposed algorithm can well reconstruct the flow patterns,and the quality of the reconstructed images is improved,which indicates that the proposed algorithm is competent to reconstruct the flow patterns in the visualization of multiphase flows. 展开更多
关键词 electrical capacitance tomography VISUALIZATION flow pattern identification dynamic reconstruction algorithm
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Long-term Decomposition Process of the Leaf Litter, Carbon and Nitrogen Dynamics under Different Forest Management in the Sierra de Francia, Salamanca, Spain
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作者 Sergio Salazar Luz-Estela Sanchez +1 位作者 Purificacion Galindo Ignacio Santa-Regina 《Journal of Agricultural Science and Technology(B)》 2012年第3期312-328,共17页
The dynamics of organic matter, carbon and nitrogen were studied during leaf decomposition over a three annual cycles period using the litterbag method at three permanently untilled and unfertilised plots. Our hypothe... The dynamics of organic matter, carbon and nitrogen were studied during leaf decomposition over a three annual cycles period using the litterbag method at three permanently untilled and unfertilised plots. Our hypothesis is to determine if each litter type influences the decomposition and C and N releases from each other litter type (three plots and two species). The main objective of this study is the comparison of decomposition dynamics in a climax forest with respect to that occurring in the chestnut managed plots on terrain suitable for oak to have further insight into the recycling of above ground organic matter and these two associated bioelements. As for the loss of dry matter, two-way analysis of variance, involving the treatment and year factors, revealed the existence of significant differences only for year, while no differences were observed for either treatment or interaction. At the end of the 2.4 years of the study, most of the treatment assays higher nitrogen concentrations than the initial ones were recorded. These three treatments the samplings prior to the last one revealed nitrogen concentrations higher than the initial ones, such that it may be concluded that the trend was towards an increase in concentration. 展开更多
关键词 Litter decomposition mass loss carbon and nitrogen release litter bags forest ecosystems Castanea sativa Quercus pyrenaica.
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OPTIMIZING THE DESIGN PARAMETER OF MINE DYNAMIC SYSTEM
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作者 宋志 白润才 +1 位作者 贾宝山 孙宝铮 《Journal of Coal Science & Engineering(China)》 1999年第1期60-66,共7页
The main contests of mire optimization design includes: mine field size, borizon and level height, mumber, shaft form and development disposal and so on. In this paper, based on mine dynamic analysis, the index functi... The main contests of mire optimization design includes: mine field size, borizon and level height, mumber, shaft form and development disposal and so on. In this paper, based on mine dynamic analysis, the index function model of mine different development stage is built up,applying dynamic programming method to find the solution of system’s optimum value,which makes the optimized result of mine dynamic design parameter more comprehensive, sysematical and reasonable. Through theory analysis research and practical validation, the obtained design parameters are reasonable and accurate. 展开更多
关键词 dynamic analysis index function design parameter
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ANALYSIS ON SPATIAL DIFFERENCE OF LAND USECHANGE BASED ON PHYSICAL AND CULTURALLANDSCAPE ATTRIBUTES──A Case Study at Mongolian AutonomousCounty of Qian Gorlos, Jilin Province 被引量:3
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作者 HUANG Fang, LIU Xiang-nan, XU Hong-mei, ZHANG Shu-wen, ZHANG Yang-zhen (Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P. R. China School of Urban and Environmental Science, Northeast Normal University, Changchun 13 《Chinese Geographical Science》 SCIE CSCD 2001年第1期50-56,共7页
Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-tempor... Land use changes are regarded as landscape pattern change driven by many interactive natural and social-economic factors. Different combination of physical geographical elements induced the difference of spatio-temporal pattern of land use change. There are four physical geographical regions in Mongolian Autonomou County of Qian Gorlos of Jilin Province. Based on spatial analysis and statistical analysis, we conclude that the primary pattern of land use and the tendency of land use changes are all different in four physical geographical regions. During 1987 – 1996, the dominant land use change processes were from grassland or forest to arableland, from unused land to paddy and grassland to unused land. Though land use change is mainly affected by social and economic condition in short period, the composite characters of physical geographical elements controls land use dynamic process. The relationship between land use dynamic process and the character of physical geographical units differ in different regions. Possible human impacts on land use change are explored with application of buffer areas of series distance along main roads and radius around main settlements. A few models are built to describe the relationship between land use spatial change rates and distance to road and settlements. According to our result, the relationship with the proximity to roads was a negative liner function, with the change rate decreasing rapidly when moving away from roads. Within a distance of less 7.5km from main traffic lines, land use changes occur red more. The bulk of grassland was apt to be opened up for cultivation around the settlements and the transformation from dryland to paddy occurred within the distance of 1km away from settlements. 展开更多
关键词 land use change physical geographic region land use dynamic process effective coefficient cultural landscape variable
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Research of Dynamic Variations in the Gravitational Field of Forthcoming Volcano Eruption
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作者 V.I. Korochentsev P.P. Sherbakov E.V. Lisunov 《Journal of Environmental Science and Engineering》 2011年第6期781-784,共4页
There is expounded the theory of"gravitational" wave propagation from the volcano crater (magma) under changing density of magma mass inside the volcano. It was revealed that while the abruptly accelerated magma m... There is expounded the theory of"gravitational" wave propagation from the volcano crater (magma) under changing density of magma mass inside the volcano. It was revealed that while the abruptly accelerated magma movement during starting period began eruption, the registered "gravitational" waves were being emitted and were propagating with the velocity greater than that of sound and seismic waves velocity. Alteration of "gravitational" waves velocity under the magma movement can be additional feature in prognosis of the start time of volcano eruption. The considered method might be effective when making up prognoses of underwater volcano eruption. 展开更多
关键词 VOLCANO EARTHQUAKE gravitational waves
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Network traffic flow evolution with battery electric vehicles and conventional gasoline vehicles
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作者 Li Manman Lu Jian +1 位作者 Sun Jiahui Tu Qiang 《Journal of Southeast University(English Edition)》 EI CAS 2019年第2期213-219,共7页
In order to investigate the effect of the use of battery electric vehicles on traffic dynamics,the valid paths of electric battery vehicles are defined and a check-based method is proposed to obtain them.Then,assuming... In order to investigate the effect of the use of battery electric vehicles on traffic dynamics,the valid paths of electric battery vehicles are defined and a check-based method is proposed to obtain them.Then,assuming that travelers only focus on their past travel experience,a day-to-day traffic assignment model is established based on reinforcement learning and bounded rationality.In the proposed model,the Bush-Mosteller model,a reinforcement learning model,is modified to calculate path choice probability according to bounded rationality.The modified model updates the path choice probability only if the gap between expected travel time and perceived travel time is beyond the cognitive threshold.Numerical experiments validate the effectiveness of the model and show that traffic flows can converge to the equilibrium in any case of cognitive thresholds and penetration rates of battery electric vehicles.The cognitive threshold has a positive influence on the variation of traffic flows while it has a negative influence on the differences between traffic flows.The adaptation of battery electric vehicles leads to the poor performance of the traffic system. 展开更多
关键词 battery electric vehicles constrained path reinforcement learning bounded rationality traffic dynamics
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保持和提高油层产能的综合工艺
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作者 胡业文 冯鼎 冯耀忠 《国外油田工程》 2010年第7期7-8,54,共3页
为了保持和提高地层的产能,开发成功了可排出地层无机、有机、液态、黏塑和固态堵塞物的地层超声波物理化学处理工艺;可稳定黏土和快速排出堵塞物的盐酸和聚丙烯酸处理工艺;可降低酸岩反应速度的微乳酸处理工艺。给出了这类新工艺的工... 为了保持和提高地层的产能,开发成功了可排出地层无机、有机、液态、黏塑和固态堵塞物的地层超声波物理化学处理工艺;可稳定黏土和快速排出堵塞物的盐酸和聚丙烯酸处理工艺;可降低酸岩反应速度的微乳酸处理工艺。给出了这类新工艺的工艺过程,矿场使用结果表明,这类工艺是高效的,既可用于油井,也可用于注水井,在油田开发晚期采用这类新工艺,可提高油井的产油量和地层采收率。 展开更多
关键词 综合工艺 动态超声波物理化学处理 盐酸-聚丙烯酸酸化 微乳酸酸化提高油层产能
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Dynamic and steady control of quantum coherence in photonic crystals via the Zeeman effect 被引量:2
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作者 CHEN LuZhou HUANG YongGang +1 位作者 JIN ChongJun WANG XueHua 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第12期2300-2304,共5页
The dynamic evolution of a multi-level atom in the three-dimensional photonic crystal under an applied magnetic field is investigated.By combining the Zeeman effect with the photonic band gap effect,the dynamic quantu... The dynamic evolution of a multi-level atom in the three-dimensional photonic crystal under an applied magnetic field is investigated.By combining the Zeeman effect with the photonic band gap effect,the dynamic quantum superposition states and steady quantum coherent trapping states of the atom can be flexibly controlled.This paves the way for coherent manipulation of quantum states in the solid-state system,which has important applications in quantum information processing. 展开更多
关键词 quantum superposition state control of quantum coherence photonic crystal gap Zeeman effect
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Evolutionary algorithm based on dynamical structure of membrane systems in uncertain environments
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作者 Chuang Liu Linan Fan 《International Journal of Biomathematics》 2016年第2期1-16,共16页
In this paper, a new evolutionary algorithm based on a membrane system is proposed to solve the dynamic or uncertain optimization problems. The proposed algorithm employs objects, a dynamical membrane structure and se... In this paper, a new evolutionary algorithm based on a membrane system is proposed to solve the dynamic or uncertain optimization problems. The proposed algorithm employs objects, a dynamical membrane structure and several reaction rules of the membrane systems. The object represents a candidate solution of the optimization problems. The dynamical structure consists of the nested membranes where a skin membrane contains several membranes, which is useful for the proposed algorithm that finds optimal solutions. The reaction rules are designed to locate and track the optimal solutions of the dynamic optimization problems (DOPs), which are inspired by processing the chemical compounds in the region of cellular membranes. Experimental study is conducted based on the moving peaks benchmark to evaluate the performance of the proposed algorithm in comparison with three state-of-the-art dynamic optimization algorithms. The results indicate the proposed algorithm is effective to solve the DOPs. 展开更多
关键词 Membrane systems membrane algorithm dynamic optimization problems.
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The dynamical evolution theory of the isolated oasis system
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作者 LI YaoKun CHAO JiPing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第3期436-447,共12页
Assume that an oasis and its surrounding desert consist of an isolated system without mass and energy exchange with the outer environment.The characteristics of oasis evolution have been explored under the condition o... Assume that an oasis and its surrounding desert consist of an isolated system without mass and energy exchange with the outer environment.The characteristics of oasis evolution have been explored under the condition of system energy conservation.The results show that oasis evolves with two equilibrium states.The first equilibrium suggests a stable expansive and an unstable degraded oasis whereas the second equilibrium indicates a stable shrink and an unstable increase of the oasis area.If one equilibrium state is unstable,the components of the isolated system(oasis and desert) would tend to be no energy exchange and they each reach to energy balance respectively.Oasis would maintain its initial area in this case.Further analyses point out that the two equilibrium states have completely different characteristics.In the first equilibrium state,a higher vegetation albedo,lower soil albedo and larger canopy resistance,and direr soil both contribute to the oasis area expansion,accompanying an excessive large desert soil and vegetation canopy temperature difference(SCTD).In the second equilibrium state,however,a lower vegetation albedo,higher soil albedo and small canopy resistance,and wetter soil benefit the oasis area to stay near its initial value,following a moderate SCTD.The convergent trajectories of the initial values in phase space are influenced by the separatrices of the equilibrium points.Higher temperature is an advantage factor for initial values convergent to the oasis expansion solution. 展开更多
关键词 energy conservation OASIS DESERT two equilibrium states
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