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Spatiotemporal characteristics and driving mechanisms of land use/land cover(LULC)changes in the Jinghe River Basin,China
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作者 WANG Yinping JIANG Rengui +4 位作者 YANG Mingxiang XIE Jiancang ZHAO Yong LI Fawen LU Xixi 《Journal of Arid Land》 SCIE CSCD 2024年第1期91-109,共19页
Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and... Understanding the trajectories and driving mechanisms behind land use/land cover(LULC)changes is essential for effective watershed planning and management.This study quantified the net change,exchange,total change,and transfer rate of LULC in the Jinghe River Basin(JRB),China using LULC data from 2000 to 2020.Through trajectory analysis,knowledge maps,chord diagrams,and standard deviation ellipse method,we examined the spatiotemporal characteristics of LULC changes.We further established an index system encompassing natural factors(digital elevation model(DEM),slope,aspect,and curvature),socio-economic factors(gross domestic product(GDP)and population),and accessibility factors(distance from railways,distance from highways,distance from water,and distance from residents)to investigate the driving mechanisms of LULC changes using factor detector and interaction detector in the geographical detector(Geodetector).The key findings indicate that from 2000 to 2020,the JRB experienced significant LULC changes,particularly for farmland,forest,and grassland.During the study period,LULC change trajectories were categorized into stable,early-stage,late-stage,repeated,and continuous change types.Besides the stable change type,the late-stage change type predominated the LULC change trajectories,comprising 83.31% of the total change area.The period 2010-2020 witnessed more active LULC changes compared to the period 2000-2010.The LULC changes exhibited a discrete spatial expansion trend during 2000-2020,predominantly extending from southeast to northwest of the JRB.Influential driving factors on LULC changes included slope,GDP,and distance from highways.The interaction detection results imply either bilinear or nonlinear enhancement for any two driving factors impacting the LULC changes from 2000 to 2020.This comprehensive understanding of the spatiotemporal characteristics and driving mechanisms of LULC changes offers valuable insights for the planning and sustainable management of LULC in the JRB. 展开更多
关键词 land use/land cover(LULC)changes driving mechanisms trajectory analysis geographical detector(Geodetector) Grain for Green Project Jinghe River Basin
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Land use change and its driving factors in the ecological function area:A case study in the Hedong Region of the Gansu Province,China
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作者 WEI Zhudeng DU Na YU Wenzheng 《Journal of Arid Land》 SCIE CSCD 2024年第1期71-90,共20页
Land use and cover change(LUCC)is important for the provision of ecosystem services.An increasing number of recent studies link LUCC processes to ecosystem services and human well-being at different scales recently.Ho... Land use and cover change(LUCC)is important for the provision of ecosystem services.An increasing number of recent studies link LUCC processes to ecosystem services and human well-being at different scales recently.However,the dynamic of land use and its drivers receive insufficient attention within ecological function areas,particularly in quantifying the dynamic roles of climate change and human activities on land use based on a long time series.This study utilizes geospatial analysis and geographical detectors to examine the temporal dynamics of land use patterns and their underlying drivers in the Hedong Region of the Gansu Province from 1990 to 2020.Results indicated that grassland,cropland,and forestland collectively accounted for approximately 99% of the total land area.Cropland initially increased and then decreased after 2000,while grassland decreased with fluctuations.In contrast,forestland and construction land were continuously expanded,with net growth areas of 6235.2 and 455.9 km^(2),respectively.From 1990 to 2020,cropland was converted to grassland,and both of them were converted to forestland as a whole.The expansion of construction land primarily originated from cropland.From 2000 to 2005,land use experienced intensified temporal dynamics and a shift of relatively active zones from the central to the southeastern region.Grain yield,economic factors,and precipitation were the major factors accounting for most land use changes.Climatic impacts on land use changes were stronger before 1995,succeeded by the impact of animal husbandry during 1995-2000,followed by the impacts of grain production and gross domestic product(GDP)after 2000.Moreover,agricultural and pastoral activities,coupled with climate change,exhibited stronger enhancement effects after 2000 through their interaction with population and economic factors.These patterns closely correlated with ecological restoration projects in China since 1999.This study implies the importance of synergy between human activity and climate change for optimizing land use via ecological patterns in the ecological function area. 展开更多
关键词 land use land type geographic detector driving mechanism Hedong Region
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A Comprehensive Evaluation Framework of Water-Energy-Food System Coupling Coordination in the Yellow River Basin,China 被引量:4
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作者 YIN Dengyu YU Haochen +3 位作者 LU Yanqi ZHANG Jian LI Gensheng LI Xiaoshun 《Chinese Geographical Science》 SCIE CSCD 2023年第2期333-350,共18页
For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governan... For mankind’s survival and development,water,energy,and food(WEF)are essential material guarantees.In China,however,the spatial distribution of WEF is seriously unbalanced and mismatched.Here,a collaborative governance mechanism that aims at nexus security needs to be urgently established.In this paper,the Yellow River Basin in China with a representative WEF system,was selected as a case.Firstly,a comprehensive framework for WEF coupling coordination was constructed,and the relationship and mechanism between them were analyzed theoretically.Then,we investigated the spatiotemporal characteristics and driving mechanisms of the coupling coordination degree(CCD)with a composite evaluation method,coupling coordination degree model,spatial statistical analysis,and multiscale geographic weighted regression.Finally,policy implications were discussed to promote the coordinated development of the WEF system.The results showed that:1)WEF subsystems showed a significant imbalance of spatial pattern and diversity in temporal changes;2)the CCD for the WEF system varied little and remained at moderate coordination.Areas with moderate coordination have increased,while areas with superior coordination and mild disorder have decreased.In addition,the spatial clustering phenomenon of the CCD was significant and showed obvious characteristics of polarization;and 3)the action of each factor is self-differentiated and regionally variable.For different factors,GDP per capita was of particular importance,which contributed most to the regional development’s coupling coordination.For different regions,GDP per capita,average yearly precipitation,population density,and urbanization rate exhibited differences in geographical gradients in an east-west direction.The conclusion can provide references for regional resource allocation and sustainable development by enhancing WEF system utilization efficiency. 展开更多
关键词 water-energy-food(WEF) comprehensive framework coupling coordination relationship driving mechanism Yellow River Basin China
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DYNAMICS OF THE LOOPER DRIVE MECHANISM ON A BLIND STITCHING MACHINE
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作者 项靖安 史荣生 《Journal of China Textile University(English Edition)》 EI CAS 1990年第4期54-62,共9页
The looper drive mechanism is a main moving part in the blind stitching machine, which is aspatial 5 bar RRRSR linkage. In this paper, a dynamic analysis of the looper drive mechanism is made by means of the ma-trix m... The looper drive mechanism is a main moving part in the blind stitching machine, which is aspatial 5 bar RRRSR linkage. In this paper, a dynamic analysis of the looper drive mechanism is made by means of the ma-trix method. Two methods are adopted in the calculation of the shaking force and shaking moment, one isdone by the constraint reaction of the flame-connected kinematic parts; the other is the inertialforces of all moving links. 展开更多
关键词 BLIND STITCHING MACHINE LOOPER drive mechanism SHAKING force SHAKING MOMENT constraint reaction
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Reasonable Drive Selecting of Parallel Mechanisms Based on Screw Theory
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作者 Longqiang Qu Guowei Pan Wenliang Chen 《World Journal of Engineering and Technology》 2015年第3期259-265,共7页
By rigidizing the input joints, all possible combinations of drive selecting for the 4-PPPS parallel mechanism are analyzed based on the screw theory in this paper, and the five of them are proved to be reasonable. Th... By rigidizing the input joints, all possible combinations of drive selecting for the 4-PPPS parallel mechanism are analyzed based on the screw theory in this paper, and the five of them are proved to be reasonable. Then choosing the one as mechanical actuators, the workspace of the 4-PPPS parallel mechanism is deduced according to the rational input scheme. Finally the rationality of input scheme for this mechanism is identified on the basis of the continuity of the workspace. 展开更多
关键词 PARALLEL mechanism drive Selecting SCREW theory WORKSPACE
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Quantitative distinction of the relative actions of climate change and human activities on vegetation evolution in the Yellow River Basin of China during 1981-2019 被引量:5
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作者 LIU Yifeng GUO Bing +3 位作者 LU Miao ZANG Wenqian YU Tao CHEN Donghua 《Journal of Arid Land》 SCIE CSCD 2023年第1期91-108,共18页
Under the combined influence of climate change and human activities,vegetation ecosystem has undergone profound changes.It can be seen that there are obvious differences in the evolution patterns and driving mechanism... Under the combined influence of climate change and human activities,vegetation ecosystem has undergone profound changes.It can be seen that there are obvious differences in the evolution patterns and driving mechanisms of vegetation ecosystem in different historical periods.Therefore,it is urgent to identify and reveal the dominant factors and their contribution rates in the vegetation change cycle.Based on the data of climate elements(sunshine hours,precipitation and temperature),human activities(population intensity and GDP intensity)and other natural factors(altitude,slope and aspect),this study explored the spatial and temporal evolution patterns of vegetation NDVI in the Yellow River Basin of China from 1989 to 2019 through a residual method,a trend analysis,and a gravity center model,and quantitatively distinguished the relative actions of climate change and human activities on vegetation evolution based on Geodetector model.The results showed that the spatial distribution of vegetation NDVI in the Yellow River Basin showed a decreasing trend from southeast to northwest.During 1981-2019,the temporal variation of vegetation NDVI showed an overall increasing trend.The gravity centers of average vegetation NDVI during the study period was distributed in Zhenyuan County,Gansu Province,and the center moved northeastwards from 1981 to 2019.During 1981-2000 and 2001-2019,the proportion of vegetation restoration areas promoted by the combined action of climate change and human activities was the largest.During the study period(1981-2019),the dominant factors influencing vegetation NDVI shifted from natural factors to human activities.These results could provide decision support for the protection and restoration of vegetation ecosystem in the Yellow River Basin. 展开更多
关键词 vegetation evolution driving mechanisms climate change human activities relative actions Geodetector Yellow River Basin
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Microstructure and mechanical properties of continuous drive friction welded Ti_(2)AlNb alloy under different rotational rates
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作者 Zhi-qiang BU Xiu-ping MA +3 位作者 Jia-yun WU Zhen LÜ Hu CHEN Jin-fu LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3221-3232,共12页
Ti_(2)AlNb-based alloy was joined in a continuous drive friction welding machine under different rotational rates(500,1000 and 1500 r/min).The microstructure and mechanical properties of the joints were investigated.I... Ti_(2)AlNb-based alloy was joined in a continuous drive friction welding machine under different rotational rates(500,1000 and 1500 r/min).The microstructure and mechanical properties of the joints were investigated.It is shown that the weld zone(WZ) is fully composed of recrystallized B2 phase,and the grain size decreases with increasing rotational rate.The thermo-mechanically affected zone(TMAZ) suffers severe deformation during welding,due to which most of original precipitation phase is dissolved and streamlines are present.In the heat affected zone(HAZ),only the fine O phase is dissolved.The as-welded joint produced using 1000 r/min has the best mechanical properties,whose strength and elongation are both close to those of the base metal,while the as-welded joint obtained using 500 r/min exhibits the worst mechanical properties.Post-weld annealing treatment annihilates the deformation microstructure and fine O phase precipitates in the joints,consequently improving the mechanical properties significantly.Decomposed α_(2) phase is a weakness for the mechanical performance of the joint since microcracks are apt to form in it in the tensile test. 展开更多
关键词 Ti2AlNb alloy continuous drive friction welding MICROSTRUCTURE mechanical properties
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Dual Instinct and Structural Theories: DSM-5-TR
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作者 Lawrence Greenman 《Open Journal of Psychiatry》 2024年第4期374-379,共6页
The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding de... The genetic based Dual Instinct Theory is determined by evolutionary history. Aggression is required for survival and sex for propagation of species. Aggressive and sexual drive derivatives with their corresponding defence mechanisms are combined with biologically based stages of infant/child development and the functional entity of Structural Theory. This model of human nature is the applied to the diagnostic categories of DSM-5-TR. Objectives: To follow the innate Dual Instinct Theory from life to death and through Artificial Intelligence;connect it with biological stages of development of the Structural Theory and illustrate its manifestations in DSM-5-TR classifications. Method: Review of selected published literature. Applying the principle of focus and cognition of informed clinical observation of innate drive derivatives in conjunction with The Structural Theory. Both theories are functional entities with no structures involved. Sigmund Freud’s biologically based stages of development;oral, anal, genital pubic, adult, and geriatric along with a variety of unconscious, automatic, and persistent defense mechanisms are selectively folded into diagnosis listed in the manual. 展开更多
关键词 Dual Instincts Structural theory Stages of Development drive Derivatives mechanisms of Defense
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Driving forces and their relative contributions to hydrocarbon expulsion from deep source rocks: A case of the Cambrian source rocks in the Tarim Basin
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作者 Bo Pang Jun-Qing Chen +2 位作者 Xiong-Qi Pang Tao Hu Yue Sheng 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期20-33,共14页
To thoroughly understand the dynamic mechanism of hydrocarbon expulsion from deep source rocks,in this study,five types of hydrocarbon expulsion dynamics(thermal expansion,hydrocarbon diffusion,compaction,product volu... To thoroughly understand the dynamic mechanism of hydrocarbon expulsion from deep source rocks,in this study,five types of hydrocarbon expulsion dynamics(thermal expansion,hydrocarbon diffusion,compaction,product volume expansion,and capillary pressure difference(CPD))are studied.A model is proposed herein to evaluate the relative contribution of different dynamics for hydrocarbon expulsion using the principle of mass balance,and the model has been applied to the Cambrian source rocks in the Tarim Basin.The evaluation results show that during hydrocarbon expulsion from the source rocks,the relative contribution of CPD is the largest(>50%),followed by compaction(10%-40%),product volume expansion(5%-30%),and thermal expansion(2%-20%).The relative contribution of diffusion to hydrocarbon expulsion is minimal(<10%).These results demonstrate that CPD plays an important role in the hydrocarbon expulsion process of deep source rocks.The hydrocarbon expulsion process of source rocks can be categorized into three stages based on the contribution of different dynamics to the process:the first stage is dominated by compaction and diffusion to expel hydrocarbons,the second stage is dominated by product volume expansion and CPD,and the third stage is dominated by product volume expansion and CPD.This research offers new insights into hydrocarbon exploration in tight oil and gas reservoirs. 展开更多
关键词 Driving force Dynamic mechanism Hydrocarbon expulsion Deep oil and gas exploration Tarim Basin
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The Evolution of a Karst Rocky Desertification Land Ecosystem and Its Driving Forces in the Houzhaihe Area, China 被引量:10
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作者 Yangbing Li Jing Xie +2 位作者 Guangjie Luo Hua Yang Shijie Wang 《Open Journal of Ecology》 2015年第10期501-512,共12页
Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzha... Understanding the evolution of karst rocky desertification (KRD) quantitatively is essential to obtain objective knowledge about the concept of KRD and the form reason of KRD, and is useful to restore KRD land. Houzhaihe area located in central plateau in Guizhou Province was studied here as a representative assemblage landform and its KRD’ s evolution and driving factors were studied, based mainly on high-resolution remote sensing image in 1963, 1978, 2005 and 2010. The KRD land comprises light KRD, moderate KRD and severe KRD. The results demonstrated that the evolution process of KRD can be divided into four modes such as unchanged, weakened, fluctuated and aggravated in the study area. The KRD with no changes from 1963 to 2010, namely, unchanged mode, accounted for 43.76% of the total area of the KRD in 2010;it distributed in the area with the slope of 15&#176 - 25&#176 and >25&#176 basically. Furthermore, the severe KRD distributed mainly in the areas within 300 - 600 m distance from settlement;when the distance away from the rural settlements was more than 900 m, the severe KRD declined, and its proportion was 28.6% and 10.6% in 1963 and 2010 respectively. In the peak-cluster depressions, located in central study area, the slope cropland with slope of 15&#176 - 25&#176 was still abounding, and was seriously rocky desertification generally. So, we propose that the existence of a large number of slope croplands is still the major driving factor of land rocky desertification. Therefore, for the rocky desertification control, the authors consider that the focal point is to alter the land use of steep-slope cropland at present. 展开更多
关键词 KARST Rocky DESERTIFICATION EVOLUTION Driving mechanism Central PLATEAU in GUIZHOU
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China's Development Modeli:the Costs and Benefits of the Decentralization Approach to Transition 被引量:1
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作者 张晏 王永钦 +2 位作者 章元 陈钊 陆铭 《China Economist》 2007年第4期22-33,共12页
This article provides a coherent framework within which to understand China’s development model,as well as the successes and the failures of China’s decentralization approach to reform.The combination of political c... This article provides a coherent framework within which to understand China’s development model,as well as the successes and the failures of China’s decentralization approach to reform.The combination of political centralization and economic decentralization provide local government with enough incentives to develop local economies,in particular incentives to promote market privatisation locally.However,the relative evaluation-based incentive schemes lead to inter- regional market segmentation,increasing inter-regional development gaps and the unequal provision of certain public goods.The success of early-stage reform can be attributed to the benefits of the decentralization approach.The next stage reform should however focus on minimizing the associated costs.China’s gradualist reform can be seen as a mechanism design issue under the control of central government.Therefore,it is essential to take both the costs and benefits of the decentralization approach into account in the design of the next-stage reform package. 展开更多
关键词 DECENTRALIZATION APPROACH benefitS COSTS mechanism design
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Spatio-temporal Evolution Characteristics and Driving Mechanism of the New Infrastructure Construction Development Potential in China 被引量:1
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作者 GU Tianshi ZHANG Peng ZHANG Xujia 《Chinese Geographical Science》 SCIE CSCD 2021年第4期646-658,共13页
With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digi... With the advent of the era of big data and artificial intelligence, new infrastructure construction(NIC) has attracted the attention of many countries. The development of NIC provides an opportunity to bridge the digital divide and narrow the regional gap,providing continuous impetus to further promote economic development. Here, we considered 31 provincial-level administrative units in China(not including Hong Kong, Macao, and Taiwan of China due to data unavailable) and established comprehensive evaluation indicators for the development potential of NIC. Afterward, we used the entropy-weight TOPSIS model to determine the development potential of NIC and analyze its spatio-temporal evolution characteristics. Furthermore, the GeoDetector model was applied to explore the driving mechanism of the NIC development potential. The conclusions were as follows: (1) The Chinese NIC development potential is generally low. The eastern China was the region with the highest development potential year by year, while the development potential in the central China was found to be in an accelerating phase. (2) The evolution of the Chinese NIC development potential’s spatial pattern has been characterized by an inland extension and coastal agglomeration. Moreover, we identified a superior development zone, a rising development zone, an inferior development zone, and a declining development zone. (3) The scope of Chinese NIC development potential agglomeration areas has gradually expanded and its degree has gradually deepened. The range of high-value agglomeration in eastern area gradually expanded and its degree gradually deepened. (4) Investment in innovative talents appears as the core factor affecting the Chinese NIC development potential. Whether acting alone or synergistically with other factors, its promoting effect on Chinese NIC development potential is the strongest. 展开更多
关键词 new infrastructure construction development potential spatio-temporal evolution driving mechanism China
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Spatial-temporal pattern and formation mechanism of county urbanization on the Chinese Loess Plateau 被引量:1
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作者 SONG Yong-yong MA Bei-bei +3 位作者 DAI Lan-hai XUE Dong-Qian XIA Si-you WANG Peng-tao 《Journal of Mountain Science》 SCIE CSCD 2021年第4期1093-1111,共19页
Urbanization is a comprehensive and complex socioeconomic phenomenon that plays an influential role in promoting global socioeconomic development.The Loess Plateau region is an important part of the China’s ecologica... Urbanization is a comprehensive and complex socioeconomic phenomenon that plays an influential role in promoting global socioeconomic development.The Loess Plateau region is an important part of the China’s ecological security pattern,and occupies an important position in the implementation of China’s new-type urbanization strategy and the realization of the urban dream.The characteristics of the staged changes and regional differentiation of urbanization in the area from 1990 to 2018 were studied with focus on regions and subregions by selecting 341 county-level administrative units on the Chinese Loess Plateau as the research area,and employing partition analysis and geographic detector methods.This revealed the formation mechanism of the spatial differentiation pattern of urbanization on the Loess Plateau.We found that the urbanization of the Loess Plateau,previously in a slow growth phase,entered the accelerated development phase,presenting a macro pattern of high rates of urbanization in central and eastern areas and low rates in western areas.The formation of the regional differentiation patterns of urbanization on the Loess Plateau were the combined results of natural geographical and socioeconomic factors.Among these factors,the interaction of any two factors had a stronger impact on regional urbanization patterns than a single factor,which was specifically manifested as nonlinear or bi-factor enhancement effects.The findings of this paper may provide a theoretical reference and scientific basis for the scientific promotion of healthy urbanization on the Chinese Loess Plateau and the ecologically fragile areas of developing countries around the world. 展开更多
关键词 URBANIZATION Spatial-temporal pattern Influencing factors Driving mechanism Geographical detector Chinese Loess Plateau
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Carbon sink response of terrestrial vegetation ecosystems in the Yangtze River Delta and its driving mechanism 被引量:2
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作者 ZHAO Haixia FAN Jinding +1 位作者 GU Binjie CHEN Yijiang 《Journal of Geographical Sciences》 SCIE CSCD 2024年第1期112-130,共19页
The carbon cycle of terrestrial ecosystems is influenced by global climate change and human activities.Using remote sensing data and land cover products,the spatio-temporal variation characteristics and trends of NEP ... The carbon cycle of terrestrial ecosystems is influenced by global climate change and human activities.Using remote sensing data and land cover products,the spatio-temporal variation characteristics and trends of NEP in the Yangtze River Delta from 2000 to 2020 were analyzed based on the soil respiration model.The driving influences of ecosystem structure evolution,temperature,rainfall,and human activities on NEP were studied.The results show that the NEP shows an overall distribution pattern of high in the southeast and low in the northwest.The area of carbon sinks is larger than that of the carbon sources.NEP spatial heterogeneity is significant.NEP change trend is basically unchanged or significantly better.The future change trend in most areas will be continuous decrease.Compared with temperature,NEP are more sensitive to precipitation.The positive influence of human activities on NEP is mainly observed in north-central Anhui and northern Jiangsu coastal areas,while the negative influence is mainly found in highly urbanized areas.In the process of ecosystem structure,the contribution of unchanged areas to NEP change is greater than that of changed areas. 展开更多
关键词 carbon sinks terrestrial vegetation ecosystems driving mechanisms climate change human activities ecosystem structure Yangtze River Delta
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A NEW METHOD OF MECHANISM SYNTHESIS FOR BIPED ROBOTS
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作者 Tan Guanzheng Institute of Robotics, Central South University of Technology, Changsha 410083 Zhu Jianying Department of Mechanical Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 《中国有色金属学会会刊:英文版》 CSCD 1997年第1期152-156,共5页
ANEWMETHODOFMECHANISMSYNTHESISFORBIPEDROBOTS①TanGuanzhengInstituteofRobotics,CentralSouthUniversityofTechnol... ANEWMETHODOFMECHANISMSYNTHESISFORBIPEDROBOTS①TanGuanzhengInstituteofRobotics,CentralSouthUniversityofTechnology,Changsha41008... 展开更多
关键词 BIPED robot mechanism SYNtheSIS harmonic GEAR drive PLANET GEAR drive
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Design of the Miniature Electrode-feeding MechanismBased on Creeping Motion
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作者 冯晓光 赵万生 +1 位作者 詹涵菁 栗岩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1998年第4期23-27,共5页
This paper describes the creeping principle. Based on this principle, a pocket-sized electrode creep-feeding mechanism applied to electrical discharge machining(EDM) is designed. Features of the mechanism: the structu... This paper describes the creeping principle. Based on this principle, a pocket-sized electrode creep-feeding mechanism applied to electrical discharge machining(EDM) is designed. Features of the mechanism: the structure of two-layer parallel plate is employed as its moving pairs, and an integral structure is adoped in the design of the mechanism. This mechanism can drive an electrode by piezoelectric element in steps of order of nanometer (the minimum feeding step of 78nm). 展开更多
关键词 ELECTRODE CREEP direct drive mechanism PIEZOELECTRIC element EDM
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A New Method of Mechanism Synthesis for Biped Robots
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作者 谭冠政 《High Technology Letters》 EI CAS 1996年第1期22-25,共4页
For a biped robot,the most essential components are its joints,including hip,knee,and ankle joints.In this paper,the construction method of a new type of joint is proposed.The main feature of this joint is that a comb... For a biped robot,the most essential components are its joints,including hip,knee,and ankle joints.In this paper,the construction method of a new type of joint is proposed.The main feature of this joint is that a combined transmission consisting of harmonic geardrive and planet gear drive is adopted in its system,and it possesses smaller volume,greaterdriving torque,and fine-looking appearance.Using this type of joint,a practical biped robotnamed NAIWR-I was constructed.The computer simulations and experiments with NAI-WR-I robot show that the method of mechanism synthesis proposed in this paper is reason-able and feasible. 展开更多
关键词 BIPED robot mechanism synthesis HARMONIC GEAR drive PLANET GEAR drive
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Research on Inner Mechanism and KDTIM Theory of Knowledge Discovery 被引量:2
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作者 YangBingru LiXin SongWei 《工程科学(英文版)》 2004年第1期46-51,共6页
The inner mechanisms were put forward solely by the author Yang Bingru. Among the inner mechanisms the double base coope\|rating mechanism, double basis fusion mechanism and information increasing mechanism are introd... The inner mechanisms were put forward solely by the author Yang Bingru. Among the inner mechanisms the double base coope\|rating mechanism, double basis fusion mechanism and information increasing mechanism are introduced in this paper. The expansibility structural models of KD (Knowledge discovery) are described including KDD *, KDK *, KD (D&K) and DFSSM, etc.. Some innovative methods, such as a mining algorithm and auto evaluation method are introduced. On the basis of all above parts, KDTIM (Knowledge discovery theory based on inner mechanism) theory is the advanced theory, and explaination of the mainstream driving to KD brought by research on inner mechanism and KDTIM is presented. 展开更多
关键词 KDTIM理论 主流驱动 内部机械 开矿机械 双基合作机械 扩展结构模型
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Sheet material lifting mechanism of the manipulator
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作者 Hong Chao Zou Congcong +2 位作者 Huang Bingshun Zhang Li Jin Aimin 《Computer Aided Drafting,Design and Manufacturing》 2016年第3期44-48,共5页
At present, machine fixed up and down repeatedly work is done by human. Although it is low cost and easy to change plate, there are many shortcomings of the work injury and the low work efficiency. Foreign automatic l... At present, machine fixed up and down repeatedly work is done by human. Although it is low cost and easy to change plate, there are many shortcomings of the work injury and the low work efficiency. Foreign automatic loading and unloading device has been developed, but the principle is more complex, the cost is higher, the energy consumption is larger, so the automatic loading and unloading robot came into being. Aiming at the transportation of mechanical raw material, an automatic device is designed to transport the scheduled raw materials to the specified position according to the processing requirements. The device has the characteristics of the simple operation, the rapid response and the large range of activities, and has obvious economic and environmental benefits. There is certain popularization value. 展开更多
关键词 MANIPULATOR lifting mechanism hydraulic drive motor silicon steel sheet
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Study on the Promoting Mechanism of Teachers'Ethics Internalization in Universities
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作者 Shan Chang 《Journal of Contemporary Educational Research》 2021年第3期82-86,共5页
On the basis of clarifying the teachers'Ethics internalization theory,this paper analyzes the typical dilemma in teachers'Ethics internalization.To resolve these problems,this paper construct an overall framew... On the basis of clarifying the teachers'Ethics internalization theory,this paper analyzes the typical dilemma in teachers'Ethics internalization.To resolve these problems,this paper construct an overall framework,including security mechanism,normative mechanism,education mechanism,evaluation mechanism and supervision mechanism,which the external conditions are used to constantly strengthen the moral needs of the subject,then enhance the consciousness of moral internalization,improve the effectiveness of teachers'moral construction. 展开更多
关键词 Teachers'ethics INTERNALIZATION Promoting mechanism External driving force Ethics standard
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