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Phragmen-Lindelof Alternative Results for the Linear Viscoelastic Damped Wave Equation
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作者 SHI Jincheng LIU Yan LIN Yiwu 《应用数学》 北大核心 2025年第2期508-516,共9页
In this article,the viscoelastic damped was equation in three-dimensional cylindrical domain were studied by using a second-order differential inequality.We proved a Phragm´en-Lindelof alternative results,i.e.,th... In this article,the viscoelastic damped was equation in three-dimensional cylindrical domain were studied by using a second-order differential inequality.We proved a Phragm´en-Lindelof alternative results,i.e.,the smooth solutions either grow or decay exponentially as the distance from the entry section tends to infinity.Our results can be seen as a version of the Saint-Venant principle. 展开更多
关键词 Fractional integral commutators Variable exponent Herz-Hardy space Variable exponent weak Herz space Variable kernel
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Opto-mechanical-thermal integration analysis of Doppler asymmetric spatial heterodyne interferometer
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作者 WANG Jin-jiang JIANG Lun +3 位作者 TONG Shou-feng PEI Hui-yi CUI Yong GUO Ming-hang 《中国光学(中英文)》 EI CAS CSCD 北大核心 2024年第6期1489-1511,共23页
In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation betw... In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications. 展开更多
关键词 Doppler asymmetric spatial heterodyne interferometer interference module imaging optical system opto-mechanical thermal integration analysis phase error temperature control
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The Theory of Adaptation of the Nervous System
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作者 Cai YifaSchool of Information Systems, Kingston University, Surrey KT12EE, U.K. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1992年第2期1-12,共12页
The explanation and simulation of the natural and artificial intelligence are the central goals of the studies of Neuroscience, Psychology, Artificial Intelligence and Cognitive Science. This paper first gives an intr... The explanation and simulation of the natural and artificial intelligence are the central goals of the studies of Neuroscience, Psychology, Artificial Intelligence and Cognitive Science. This paper first gives an introduction to the core topics and approaches in the study. Then, GAF--a general adaptive framework for neural system is proposed. Interdisciplinary discussions around the adaptation of the human nervous system are presented. Rules describing the theory of adaptation of the nervous system are provided. 展开更多
关键词 nervous system Artificial intelligence General adaptive framework.
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Comparison between the 2007 and the 2016 WHO classification of tumours of the central nervous system
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《中国现代神经疾病杂志》 CAS 2016年第8期543-543,共1页
关键词 Comparison between the 2007 and the 2016 WHO classification of tumours of the central nervous system NOS WHO
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Comparison between the 2007 and the 2016 WHO Classification of Tumours of the Central Nervous System
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《中国现代神经疾病杂志》 CAS 2016年第6期381-381,共1页
关键词 WHO IDH Comparison between the 2007 and the 2016 WHO Classification of Tumours of the Central nervous system
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Comparison between the 2007 and the 2016 WHO classification of tumours of the central nervous system(Ⅰ)
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《中国现代神经疾病杂志》 CAS 2016年第10期719-719,共1页
关键词 WHO Comparison between the 2007 and the 2016 WHO classification of tumours of the central nervous system
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Layout configuration and joint scheduling optimization of green-grey-blue integrated system for urban stormwater management:Current status and future directions
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作者 DUAN Tingting LI Pengfeng +4 位作者 KHU Soonthiam HUANG Peng TIAN Tengfei LIU Qian ZHANG Yuting 《水利水电技术(中英文)》 北大核心 2025年第7期77-108,共32页
[Objective]Under the combined impact of climate change and urbanization,urban rainstorm flood disasters occur frequently,seriously restricting urban safety and sustainable development.Relying on traditional grey infra... [Objective]Under the combined impact of climate change and urbanization,urban rainstorm flood disasters occur frequently,seriously restricting urban safety and sustainable development.Relying on traditional grey infrastructure such as pipe networks for urban stormwater management is not enough to deal with urban rainstorm flood disasters under extreme rainfall events.The integration of green,grey and blue systems(GGB-integrated system)is gradually gaining recognition in the field of global flood prevention.It is necessary to further clarify the connotation,technical and engineering implementation strategies of the GGB-integrated system,to provide support for the resilient city construction.[Methods]Through literature retrieval and analysis,the relevant research and progress related to the layout optimization and joint scheduling optimization of the GGBintegrated system were systematically reviewed.In response to existing limitations and future engineering application requirements,key supporting technologies including the utilization of overground emergency storage spaces,safety protection of underground important infrastructure and multi-departmental collaboration,were proposed.A layout optimization framework and a joint scheduling framework for the GGB-integrated system were also developed.[Results]Current research on layout optimization predominantly focuses on the integration of green system and grey system,with relatively fewer studies incorporating blue system infrastructure into the optimization process.Moreover,these studies tend to be on a smaller scale with simpler scenarios,which do not fully capture the complexity of real-world systems.Additionally,optimization objective tend to prioritize environmental and economic goals,while social and ecological factors are less frequently considered.Current research on joint scheduling optimization is often limited to small-scale plots,with insufficient attention paid to the entire system.There is a deficiency in method for real-time,automated determination of optimal control strategies for combinations of multiple system facilities based on actual rainfall-runoff processes.Additionally,the application of emergency facilities during extreme conditions is not sufficiently addressed.Furthermore,both layout optimization and joint scheduling optimization lack consideration of the mute feed effect of flood and waterlogging in urban,watershed and regional scales.[Conclusion]Future research needs to improve the theoretical framework for layout optimization and joint scheduling optimization of GGB-integrated system.Through the comprehensive application of the Internet of things,artificial intelligence,coupling model development,multi-scale analysis,multi-scenario simulation,and the establishment of multi-departmental collaboration mechanisms,it can enhance the flood resilience of urban areas in response to rainfall events of varying intensities,particularly extreme rainfall events. 展开更多
关键词 excessive rainfall runoff green-grey-blue integrated system emergency response intelligent control optimization framework multi-departmental collaboration climate change flood
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Integrated Scheduling of Communication,Sensing,and Control for UAV-aided FSO Systems
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作者 LU Dingshan YU Yinchang +1 位作者 SU Daopeng WANG Jinyuan 《电讯技术》 北大核心 2025年第6期892-902,共11页
Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investig... Recently,unmanned aerial vehicle(UAV)-aided free-space optical(FSO)communication has attracted widespread attentions.However,most of the existing research focuses on communication performance only.The authors investigate the integrated scheduling of communication,sensing,and control for UAV-aided FSO communication systems.Initially,a sensing-control model is established via the control theory.Moreover,an FSO communication channel model is established by considering the effects of atmospheric loss,atmospheric turbulence,geometrical loss,and angle-of-arrival fluctuation.Then,the relationship between the motion control of the UAV and radial displacement is obtained to link the control aspect and communication aspect.Assuming that the base station has instantaneous channel state information(CSI)or statistical CSI,the thresholds of the sensing-control pattern activation are designed,respectively.Finally,an integrated scheduling scheme for performing communication,sensing,and control is proposed.Numerical results indicate that,compared with conventional time-triggered scheme,the proposed integrated scheduling scheme obtains comparable communication and control performance,but reduces the sensing consumed power by 52.46%. 展开更多
关键词 FSO communications integrated scheduling of communication sensing and control unmanned aerial vehicle(UAV)
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Adaptive sliding-mode path following control system of the underactuated USV under the influence of ocean currents 被引量:11
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作者 CHEN Xiao LIU Zhong +2 位作者 ZHANG Jianqiang ZHOU Dechao DONG Jiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1271-1283,共13页
The path-following control of the asymmetry underactuated unmanned surface vehicle(USV) under external disturbances such as unknown constant and irrational ocean currents is discussed, and an adaptive sliding-mode pat... The path-following control of the asymmetry underactuated unmanned surface vehicle(USV) under external disturbances such as unknown constant and irrational ocean currents is discussed, and an adaptive sliding-mode path-following control system is proposed, which comprises a path-variable updated law,a modified integral line-of-sight(ILOS) guidance law based on a time-varying lookahead distance and adaptive feedback linearizing controllers combined with sliding-mode technique. A more accurate USV model without the assumption of having diagonal inertia and damping matrices is first presented, aiming at improving the performance of the path-following control. Next, the coordinate transformation is adopted to decouple the sway dynamic from the rudder angle, and the path-following errors dynamics without non-singular problem are presented in the moving Frenet-Serret frame. Then, based on the cascaded theorem and the adaptive sliding-mode method, the adaptive control law of position errors and course error are designed, among which the lookahead distance and integral gain are all computed as different functions of cross-track error to estimate and compensate the sideslip angle caused by external disturbances adaptively. Finally, according to the Lyapunov and cascaded theorem, the control system proposed is proved to be uniform globally asymptotic stability(UGAS) and uniform semiglobal exponential stability(USGES) when the control objectives are all achieved. Simulation results illustrate the precision and high-quality performance of this new controller. 展开更多
关键词 sliding-mode control unmanned surface vehicle(USV) integral line-of-sight(ILOS) path following proof of stability
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Selection of the best initial orbital elements of satellite based on fuzzy integration evaluation method 被引量:3
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作者 Yang Yong'an Zhang Hongwei +1 位作者 Feng Zuren Luo Yongjin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期566-570,共5页
The fuzzy integration evaluation method (FIEM) is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT&C (Tracking, Telemetry and Control) center w... The fuzzy integration evaluation method (FIEM) is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT&C (Tracking, Telemetry and Control) center with all kinds of data sources. By employing FIEM together with the experience of TT&C experts, the index system to evaluate the selection of the best initial orbits is established after the data sources and orbit determination theories are studied. Besides, the concrete steps in employing the method are presented. Moreover, by taking the objects to be evaluated as evaluation experts, the problem of how to generate evaluation matrices is solved. Through practical application, the method to select the best initial orbital elements has been proved to be flexible and effective The originality of the method is to find a new evaluation criterion (comparing the actually tracked orbits) replacing the traditional one (comparing the nominal orbits) for selecting the best orbital elements. 展开更多
关键词 system engineering fuzzy integration evaluation method SATELLITE initial orbit TT&C system.
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Research on the integration of Web_-CNC and EIS 被引量:1
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作者 Zou Zeming Li Congxin Ruan Xueyu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第4期894-900,共7页
During the time of building enterprise information System (EIS), agility of enterprise can' t be improved entirely just through implementing the system such as: ERP, PDM, CAPP and so on. There is an information ga... During the time of building enterprise information System (EIS), agility of enterprise can' t be improved entirely just through implementing the system such as: ERP, PDM, CAPP and so on. There is an information gap between bottom rnannfacturing equipment and the top EIS, that makes against elevating the agility of enterprise. Building Web- CNC and realizing its integration with EIS is an effect way to solve this problem. The architecture of Web- CNC, the integration of Web- CNC and EIS are detailed. Lastly, an instance is analyzed and discussed. 展开更多
关键词 enterprise information system information gap Web_ CNC integration.
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Multi Model Technology and Its Application in the Integration of CAD/CAM/CAE 被引量:1
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作者 XU Xiang-yang, WANG Yan-yan (Automotive Engineering College, Harbin Institute of Technology Weiha i, Shandong 264209, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期215-216,共2页
The globalization and the intensive competition of th e automotive market require shortening the product development cycle, improving the quality and reducing the cost. Optimizing the product development process, b ui... The globalization and the intensive competition of th e automotive market require shortening the product development cycle, improving the quality and reducing the cost. Optimizing the product development process, b uilding product’s consistent defining model for life cycle, and realizing the in tegration of CAD/CAM/CAE and Concurrent Engineering (CE) become the means to acc ept the challenge. A new product modeling technology, Multi Model Technology (MM T), is provided in this paper to meet the needs of the challenge for automotive powertrain product development. First, the paper introduces the concept of Multi Model Technology. MMT introduce s Object-oriented Technology (OT) into product modeling process and combine OT with feature-based modeling technology. With the help of OT, MMT builds product object model to support system level management in product development. The obj ect model of the product is a Multi Model Structure. The MMS consists of finish part model level (assembly model level), rough part model level (part model leve l), function model level and basic model level. Every models in the MMS is creat ed by feature-based technology in design process. In this case, models in the M MS of product can be shared by casting mould, sand core and sand core mould. The refore, CAD engineers, CAE engineers and CAM engineers can work concurrently and the integration of CAD/CAM/CAE can be realized. Second, MMT is applied in cylinder head development. The multi model structures of cylinder head, its casting mould, sand core and sand core mould are built, an d the process-oriented feature models of every objects in the multi model struc tures are modeled, the application of different model objects in development pro cess is analyzed. The integrated modeling technology of cylinder head, its casti ng mould, sand core and sand core mould under MMT is studied. And the concurrent engineering oriented integration method of CAD/CAE and the method to realize th e integration of CAD/CAE under MMT are also discussed. Based on above, the integ ration of CAD/CAM/CAE of cylinder head is realized in automotive powertrain prod uct. The practice results shows that the modeling technology in this paper can optimi ze the development process, realize the data sharing and concurrent engineering in the product development process. 展开更多
关键词 modeling technology CAD/CAM/CAE integration cy linder head
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The Information Integration of CAPP in CIMS
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作者 ZHANG Yu 1, XIONG Man-chen 2 (CIMS Application and Research Center, Faculty of Mechanical and Electr onic Engineering, Kunming University of Science and Technology, Kunming 65009 3, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期182-183,共2页
This paper analyzes the flow of the process design an d the fountain of the technique data in a manufacturing enterprise, and discusse s the information flows between CAPP and other systems in CIMS, such as CAD syst e... This paper analyzes the flow of the process design an d the fountain of the technique data in a manufacturing enterprise, and discusse s the information flows between CAPP and other systems in CIMS, such as CAD syst em and Enterprise Resource Planning (ERP) system. And then, it discusses the pla ns of information integration between CAPP and CAD, as well as between CAPP and ERP. To design the processes of a product requires the manufacture information, such as blank material and machine tool, which is saved in a database in ERP. General ly, a traditional CAPP system considers the information of the manufacturing res ources, such as machine tool, as changeless. However, it is real changing, becau se the resources may be occupied or the machine tool may be under repair. Theref ore, in order to design the processes more reasonably, we must consider the real change of resources in a workshop. Creating a public resource database to suppo rt the real change of resources is put forward in this paper. With the public re source database, the resource integration between CAPP system and ERP is realize d; and by information collections in CAPP system, such as BOM, the material cons umption and man-hour consumption and their output to ERP, the information integ ration between CAPP system and ERP is realized. 展开更多
关键词 CIMS CAPP ERP information integration techniq ue data
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Analytical Properties of Solutions and First Integrals of a Class of the Third-Order Autonomous Systems
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作者 CHEN Yang I.P.Martynov 《重庆理工大学学报(自然科学)》 CAS 北大核心 2018年第6期199-204,共6页
The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of g... The paper is devoted to the analytic theory of differential equations.In paper shown that how to establish the analytical properties of solutions of an autonomous system of the third order special type(meromorphy of general solutions,instances of availability logarithmic branch points).The method for constructing the first integrals of the systems under consideration is indicated. 展开更多
关键词 MEROMORPHIC function logarithmic branch POINT FIRST INTEGRAL
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Thermal performance of integration of solar collectors and building envelopes
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作者 于国清 龚小辉 曹双华 《Journal of Central South University》 SCIE EI CAS 2009年第S1期255-258,共4页
The integration of building with solar collector was studied. The theoretical model of integration of building envelopes and flat plate solar collectors was set up and the thermal performance of integration was studie... The integration of building with solar collector was studied. The theoretical model of integration of building envelopes and flat plate solar collectors was set up and the thermal performance of integration was studied in winter and summer,and compared to envelopes without solar collectors. The results show that the solar collection efficiency is raised in the integration of building envelopes and solar collectors with the air layer doors closed. This is true whether in winter or summer. The increment is higher as the inlet water temperature increases or the ambient temperature is low. In winter,the heat loss is significantly reduced through integration of the building envelopes and solar collectors with the closed air layer doors. The integration with the open air layer door is worse than that without collectors. In summer,the heat gains of the integration of envelopes and solar collectors are more obviously reduced than envelopes without collectors,the integration with the open air layer door is a little better than the closed one,but the difference is very small. 展开更多
关键词 SOLAR COLLECTOR building ENVELOPES SOLAR COLLECTION efficiency heat TRANSFER integration
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Nanofibrous scaffolds for the regeneration of nervous tissue
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作者 Aijun Wang,Yiqian Zhu,Song Li(Department of Bioengineering,University of California,Berkeley,Berkeley,CA 94720,USA.) 《医用生物力学》 EI CAS CSCD 2010年第S1期20-21,共2页
Introductons The biophysical organization of extracellular matrix (ECM) plays an important role in tissue morphogenesis,remodeling and functions. In many types of tissues,e. g. ,blood vessel,nerve,heart,muscle,tendon ... Introductons The biophysical organization of extracellular matrix (ECM) plays an important role in tissue morphogenesis,remodeling and functions. In many types of tissues,e. g. ,blood vessel,nerve,heart,muscle,tendon and ligament,ECM has aniso- 展开更多
关键词 Nanofibrous scaffolds for the regeneration of nervous tissue PLLA
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Decision Making Support System(DSS)——A Synthesized and Integrated Crystallization of Systems Engineering, Artificial Intelligence and Electronic Technologies
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作者 汪成为 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第1期1-2,共2页
I firmly believe that of systems engineering is the requirement-driven force for the progress ofsoftware engineering, artificial intelligence and electronic technologies. The development ofsoftware engineering, artifi... I firmly believe that of systems engineering is the requirement-driven force for the progress ofsoftware engineering, artificial intelligence and electronic technologies. The development ofsoftware engineering, artificial intelligence and electronic technologies is the technical supportfor the progress of systems engineering. INTEGRATION can be considered as "bridging" the ex-isting technologies and the People together into a coordinated SYSTEM. 展开更多
关键词 Decision Making Support system Artificial Intelligence and Electronic Technologies DSS A Synthesized and Integrated Crystallization of systems Engineering
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THE CLIMATIC STUDY OF CHANGBAI MOUNTAIN BY INTEGRATION OF REMOTE SENSING INFORMATION AND GEO-CODED IMAGES
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作者 Yang Meihua Department of Geography, Northeast Normal University Wang Yeqiao Changchun Inst. of Geography, Chinese Academy of Sciences 《遥感信息》 CSCD 1990年第A02期39-40,共2页
Ⅰ. INTRODUCTION Changbai Mountain is situated between E127°54′-128°08′, N40°58′-42°06′ about 2700 meters above sea level. It is the typical area of the mountainous climate in the monsoon area ... Ⅰ. INTRODUCTION Changbai Mountain is situated between E127°54′-128°08′, N40°58′-42°06′ about 2700 meters above sea level. It is the typical area of the mountainous climate in the monsoon area of the temperate zone on the globe. The well reserved primeval vertical distribution of natural landscape belts and the Natural Conservation of Changbai Mountains adopted by the UNESCO′s MAB Program cause the worldwide attention of geographers. Beside the complexity of the climatic structure itself, the mechanical effection of the high mountain body also effect the climate in the eastern part of China. In the mountain area where short of meteorological observation data, the climatic study by remote sensing is favorable for discovery and representation of climatic law in large area. 展开更多
关键词 the CLIMATIC STUDY of CHANGBAI MOUNTAIN BY integration of REMOTE SENSING INFORMATION AND GEO-CODED IMAGES GEO data body
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A Study on the Integration of the Confucian Culture and the Core Values of China
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作者 Sun Renxiang 《学术界》 CSSCI 北大核心 2016年第6期320-324,共5页
Core value is an important guarantee for building a harmonious socialist society and the ideological and moral basis of the unity of the people of all ethnic groups in our country.In recent years,the cultivation and p... Core value is an important guarantee for building a harmonious socialist society and the ideological and moral basis of the unity of the people of all ethnic groups in our country.In recent years,the cultivation and practice of core values have become more and more popular;the main thoughts of core values derive fromtraditional culture.In retrospect of our traditional culture,Confucian culture is not allowed to be ignored.Therefore,in the process of fostering and practicing the core values,we need to analyze the combination between Confucian culture and core values,and ingeniously fuse the Confucian culture into the core values,so that the connotation of the core values would more abundant. 展开更多
关键词 儒家文化 价值观 整合 中国 传统文化 思想道德 社会 培育
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Study on the Mechanism of the Integration of Urban and Rural Development from the View of Elements Flow
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作者 Chang Ye Jin Tianlin 《学术界》 CSSCI 北大核心 2016年第6期285-290,共6页
Fromthe enterprise,individual and government,which are the three main economic behavior subject,this paper analysis factors impact of flow behavior main body and the change of the objective function,constraint functio... Fromthe enterprise,individual and government,which are the three main economic behavior subject,this paper analysis factors impact of flow behavior main body and the change of the objective function,constraint function and the impact of the change of behavior equation,and then summarizes their effects on the integration of urban and rural development,to build fromexogenous shocks to the endogenous to adapt to the economic decision-making framework,clarify elements flow affect the running mechanismof the urban-rural integration. 展开更多
关键词 城乡一体化发展 流动行为 运行机制 经济决策 行为主体 目标函数 约束函数 城乡发展
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