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上海大都市游憩商业区的型态模式研究 被引量:18
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作者 张建 《地域研究与开发》 CSSCI 北大核心 2005年第3期63-67,共5页
文章在城市游憩商业区(RBD)的研究进展基础上,采用REcEn模型,对上海都市区RBD作了识别;提出了上海都市区RBD系统存在叠加、伴生、增长极、点轴4种模式8种型态;并从城市产业结构调整、居住职能转移、商业服务业发展和行政区划等视角,探... 文章在城市游憩商业区(RBD)的研究进展基础上,采用REcEn模型,对上海都市区RBD作了识别;提出了上海都市区RBD系统存在叠加、伴生、增长极、点轴4种模式8种型态;并从城市产业结构调整、居住职能转移、商业服务业发展和行政区划等视角,探讨了大都市区RBD系统的动力机制,揭示了上海都市区RBD系统的发展趋势。 展开更多
关键词 游憩商业区 型态模式 空间结构 上海市
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电子设备制造业转型升级型态和模式选择
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作者 陈超 《通讯世界》 2023年第2期184-186,共3页
我国电子设备制造业虽然充分融入全球价值链中,但总体处于全球价值链的低端。近年来,我国制造业粗放式发展使我国在劳动力资源方面的优势逐渐丧失。因此,我国电子设备制造业进行转型升级,且已经取得了初步成效。为了推动电子设备制造业... 我国电子设备制造业虽然充分融入全球价值链中,但总体处于全球价值链的低端。近年来,我国制造业粗放式发展使我国在劳动力资源方面的优势逐渐丧失。因此,我国电子设备制造业进行转型升级,且已经取得了初步成效。为了推动电子设备制造业进一步向制造服务转型升级,要解决转型升级中所存在的缺乏核心技术、科研投入不足等问题,选择合适的转型升级型态与模式,以及采取有效的转型升级对策。 展开更多
关键词 电子设备制造业 转型升级 型态模式选择
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Finite difference method for dynamic response analysis of anchorage system 被引量:5
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作者 言志信 段建 +3 位作者 江平 刘子振 赵红亮 黄文贵 《Journal of Central South University》 SCIE EI CAS 2014年第3期1098-1106,共9页
Based on some assumptions, the dynamic analysis model of anchorage system is established. The dynamic governing equation is expressed as finite difference format and programmed by using MATLAB language. Compared with ... Based on some assumptions, the dynamic analysis model of anchorage system is established. The dynamic governing equation is expressed as finite difference format and programmed by using MATLAB language. Compared with theoretical method, the finite difference method has been verified to be feasible by a case study. It is found that under seismic loading, the dynamic response of anchorage system is synchronously fluctuated with the seismic vibration. The change of displacement amplitude of material points is slight, and comparatively speaking, the displacement amplitude of the outside point is a little larger than that of the inside point, which shows amplification effect of surface. While the axial force amplitude transforms considerably from the inside to the outside. It increases first and reaches the peak value in the intersection between the anchoring section and free section, then decreases slowly in the free section. When considering damping effect of anchorage system, the finite difference method can reflect the time attenuation characteristic better, and the calculating result would be safer and more reasonable than the dynamic steady-state theoretical method. What is more, the finite difference method can be applied to the dynamic response analysis of harmonic and seismic random vibration for all kinds of anchor, and hence has a broad application prospect. 展开更多
关键词 anchorage system dynamic response finite difference method attenuation characteristic
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Eco-compensation and Harmonious Regional Development in China 被引量:4
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作者 LIU Chunla LIU Weidong +3 位作者 LU Dadao CHEN Mingxing Michael DUNFORD XU Mei 《Chinese Geographical Science》 SCIE CSCD 2016年第3期283-294,共12页
Harmonious regional development poses difficult problems, especially in so far as the harmonious regional development of ecological resources is concerned. China has explored several eco-compensation models, and in ea... Harmonious regional development poses difficult problems, especially in so far as the harmonious regional development of ecological resources is concerned. China has explored several eco-compensation models, and in each province eco-compensation has different characteristics. These methods have had significant impacts. The aim of this paper is first to examine the meaning of ecocompensation and to present a framework for analyzing it. Next the development of eco-compensation in China is examined. Finally, four typical models of eco-compensation are compared: the government financial transfer payment compensation model; the ecological resource exploiters′ payment compensation model; the ecological destruction compensation model; and the ecological resource tax collection compensation model. Each model has its own unique feature and potential to contribute to harmonious regional development. 展开更多
关键词 eco-compensation harmonious regional development China
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Trends in per capita ecological footprint and biocapacity in China 1949-2013
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作者 Yuan Cao Chengzhong Chen Xuguang Ge 《Chinese Journal of Population,Resources and Environment》 2017年第2期175-181,共7页
This paper proposes two concepts: the ecological footprint component index(EFCI) and the biocapacity component index(BCCI), based on the ecological footprint(EF) and Shannon entropy approaches. Per capita EFCI and BCC... This paper proposes two concepts: the ecological footprint component index(EFCI) and the biocapacity component index(BCCI), based on the ecological footprint(EF) and Shannon entropy approaches. Per capita EFCI and BCCI in China 1949-2013 are analyzed using empirical mode decomposition(EMD). Nonlinear models of per capita EFCI and BCCI in China 1949-2013 are presented and their cycles and predictions from 2014 to 2023 are analyzed. The results over the last 65 years show:(1) EFCI in China has increased constantly with fluctuations, while BCCI has slowly decreased. Their annual change rates are 2.81% and-1.26%, respectively. The increasing EFCI indicates a gradual improvement in China's sustainable development potential; the decreasing BCCI indicates severe environmental and population challenges.(2) The cycles of per capita EFCI have periods of 5.4 and 16.3 years, while cycles of per capita BCCI have periods of 3.6, 13,and 21.7 years. The predictive models indicate that EFCI will first decrease, reaching 0.02725 in2014, and will subsequently increase to 0.03261 in 2021. BCCI will increase, reaching 0.01365 in2014 and 0.01541 in 2022. EFCI and BCCI will reach 0.03037 and 0.01537, respectively, in 2023.Policymakers should ensure that the EFCI and BCCI increase in 2023. 展开更多
关键词 Ecological footprint component index(EFCI) biocapacity component index(BCCI) entropy method empirical mode decomposition(EMD) dynamic model
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Research on transformation from UML statechart to interface automata 被引量:1
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作者 李良明 Wang Zhijian Tang Longye 《High Technology Letters》 EI CAS 2010年第2期152-156,共5页
This paper studies the problem of deriving an interface automata model from UML statechart, in which, interface automata is a formaliged model for describing component behavior in an open system, but there is no unive... This paper studies the problem of deriving an interface automata model from UML statechart, in which, interface automata is a formaliged model for describing component behavior in an open system, but there is no universal criterion for deriving behavior from component to construct the model. UML is a widely used modeling standard, yet it is very difficult to apply it to system verification and testing directly for its imprecise semantics. After analyzing the expression ability of the two models, several transforma- tion rules are defined and each step of transformation is described in detail, after that, the approach is illustrated with an example. The paper provides a method for acquiring interface automata and lays the foundation for related research. 展开更多
关键词 model transformation interface automata (IA) UML stateehart
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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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Developing Mechanism of Rubber-tea-chicken Agro-forestry Model in Tropical Area of China
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作者 Meng Qingyan Miao Zewei Wang Zhaoqian 《Chinese Journal of Population,Resources and Environment》 2012年第3期100-106,共7页
As a typical tropical agro-forestry ecosystem in Wenchang, Hainan Province, China, rational mechanisms of the rubber-tea-chicken eco-agricultural model were studied with the Solow technological level index, stability ... As a typical tropical agro-forestry ecosystem in Wenchang, Hainan Province, China, rational mechanisms of the rubber-tea-chicken eco-agricultural model were studied with the Solow technological level index, stability indicator, harmonizing coefficient, grey corretation coefficient and production dominance. This study focused on rational hierarchical structure, the limiting factors and optimal strategies of the model development based on model structure, resource conditions and external market demands. Results showed that rational mechanism of the rubber-tea-chicken ecosystem model mainly included technological contributions, leverage function of dominance component (livestock husbandry), stability of the model structure and harmony of its components, the model dominant product's market demand and government's supporting policies. The contributions of fund, technology, information and talent resources played an important role in improving sustainability and productivity of the agro-forestry model. 展开更多
关键词 eco-agricultural model the Solow technological levelindex stability indicator harmonizing coefficient grey correlationcoefficient
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Alternate Form of Damped Wave Conduction and Relaxation Equation a Capite Adcalcem in Temperature
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作者 Kal Renganathan Sharma 《Journal of Physical Science and Application》 2013年第1期46-53,共8页
An alternate non-Fourier heat conduction equation is derived from consideration of translation motion of spinless electron under a driving force due to an applied temperature gradient. This equation is a eapite ad cal... An alternate non-Fourier heat conduction equation is derived from consideration of translation motion of spinless electron under a driving force due to an applied temperature gradient. This equation is a eapite ad calcem,temperature. Elimination of the rate of change of velocity with respect to time leads to a non-Fourier heat conduction equation with a accumulation of temperature or ballistic term in it. The new constitutive heat conduction equation is combined with the energy balance equation in one dimension. The governing equation for transient temperature a partial differential equation (Eq. (23)) is solved for by the method of Laplace transforms. The problem considered is the semi-infinite medium with constant thermo physical properties with constant wall temperature boundary condition. A closed form analyticalexpression for the transient temperature was obtained (Eq. (36)) after truncation of higher order terms in the infinite binomial series and use of convolution and lag properties. This solution is compared with that obtained using the parabolic Fourier model and the damped wave model as presented in an earlier study. The predictions of Eq. (36) are closer to the Fourier model. The convex nature of the temperature curve is present. 展开更多
关键词 Transport theory non-fourier conduction CWT constant wall temperature binomial infinite series.
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Study on integrated calculation of ecological water demand for basin system 被引量:4
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作者 JIN Xin YAN DengHua +4 位作者 WANG Hao ZHANG Cheng TANG Yun YANG GuiYu WANG LingHe 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第10期2638-2648,共11页
The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecologi... The operation of reservoir(s) has a certain impact on the downstream hydrologic regime,and even endangers the ecological water safety of river corridor and ecosystems which interact with river system.Therefore,ecological operation needs to be carried out in order to ensure ecological water use of downstream zone.The key technological support is the estimation and integrated calculation of ecological water demand.The connotation of the integrated calculation on ecological water demand lies on that the ecological water demand of different ecosystems is integrated to meet the requirements of water allocation and operation on watershed scale in terms of hydrological cycle.Considering the practical requirement of ecological operation of reservoir(s),this study proposed an integrated calculation approach of ecological water demand according to the ecological water demand in various ecosystems as well as the hydraulic connection among them;it established an integrated calculation model of regional ecological water demand by means of the distributed hydrological model,and studied the integrated calculation in Yalong River basin which is the source area of the west route of South-North Water Transfer Project as an example.The results indicated that the integrated calculation model more effectively combined the ecological water demand and hydraulic connection of ecosystems in time and space,compared with the lumped water balance analysis,since the former conquered the defect of insufficient ecological water source and supplement on multiple spatial and temporal scales,and met the demand of ecological operation of reservoir(s). 展开更多
关键词 ecological operation of reservoir ecological water demand integrated calculation distributed hydrological model west route of South-North Water Transfer Project in Yalong River source area
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Model updating based on incomplete modal data 被引量:5
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作者 LI HuaJun WANG JunRong HU Sau-Lon James 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第7期1737-1747,共11页
The objective of model updating is to improve the accuracy of a dynamic model based on the correlation between the measured data and the analytical (finite element) model. In this paper, we intend to update the mass a... The objective of model updating is to improve the accuracy of a dynamic model based on the correlation between the measured data and the analytical (finite element) model. In this paper, we intend to update the mass and stiffness matrices of an analytical model when only modal frequencies or spatially incomplete modal data are available. While the proposed method is systematic in nature, it also preserves the initial configuration of the analytical model, and physical equality and/or inequality constraints can be easily incorporated into the solution procedure. Numerical examples associated with a simple 5-DoF (degree of freedom) mass-spring system are chosen to illustrate the detailed procedure and the effectiveness of the proposed method. Numerical scenarios ranging from the updating for stiffness terms only to that for all mass and stiffness terms based on various kinds of incomplete modal data are studied. The obtained model updating results are excellent when the measured modal data are noise-free. Uncertainty studies are also conducted based on simulations of corrupted modal data, but a thorough theoretical analysis of the noise effect on the proposed method is still needed. 展开更多
关键词 model updating model reduction modal expansion incomplete mode
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Quasi-Conical Quantum Dot: Electron States and Quantum Transitions
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作者 Eduard M.Kazaryan Lyudvig S.Petrosyan +1 位作者 Vanik A.Shahnazarya Hayk A.Sarkisyan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第2期255-260,共6页
The exactly solvable model of quasi-conical quantum dot, having a form of spherical sector, is proposed. Due to the specific symmetry of the problem the separation of variables in spherical coordinates is possible in ... The exactly solvable model of quasi-conical quantum dot, having a form of spherical sector, is proposed. Due to the specific symmetry of the problem the separation of variables in spherical coordinates is possible in the one- electron Sehrodinger equation. Analytical expressions for wave function and energy spectrum are obtained. It is shown that at small values of the stretch angle of spherical sector the problem is reduced to the conical QD problem. The comparison with previously performed works shows good agreement of results. As an application of the obtained results, the quantum transitions in the system are considered. 展开更多
关键词 conical quantum dot electron states quantum transitions
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Kinetic theory for aquatic animal distribution simulation
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作者 FANG Hong Wei DAI Dong Chen +3 位作者 LI Song Heng HE Guo Jian HUANG Lei PENG Wen Qi 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第12期1856-1866,共11页
Identifying the underlying mechanisms that influence the spatial patterns in populations improves the forecasts of the alternative management strategies on the spatial dynamics of the populations, which are critical f... Identifying the underlying mechanisms that influence the spatial patterns in populations improves the forecasts of the alternative management strategies on the spatial dynamics of the populations, which are critical for assessing and managing the fisheries and improving the water resource management. This paper described a new approach of the numerical model for the prediction of the aquatic animal distribution in the flows. The model was developed based on the kinetic theory of gases, the mechanism of the aquatic animal movement and the flow hydrodynamic patterns. The model was validated using the available experimental data and an acceptable agreement was obtained. A comprehensive parameter study was then conducted to help understand the impact and the sensitivity of each parameter to the aquatic animal distribution. The promising results of the model reveal the prospect of applying this model to the reliable prediction of the aquatic animal distribution within a relatively large water area. 展开更多
关键词 kinetic theory aquatic animal distribution Euler aquatic animal swimming behavior
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