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    题名 作者 年代 出处 被引量
1HYDRAULICS OF COMPOUND CHANNEL WITH VEGETATED FLOODPLAINS显示文摘Experimental researches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. Results show that hydrodynamic behavior of compound channels with narrow floodplains is different from that of the wide floodplains. In such compound channels with narrow vegetated floodplains as in the Pearl River delta nework, it has been found that vegetated domains become really impenetra ble when the length of vegetated domain is larger than Lm, the length of f low in floodplain coming into the main channel, and that the influence of vegeta ted floodplains upon flood stages of a channel is not very significant.Huang Ben-sheng, Lai Guan-wen, Qiu Jing, Lin Shu-zhong (Guangdong Research Institute of Water Conservancy & Hydro-Power, Guangzhou 510610, China 2002Journal of Hydrodynamics2002,14,1:21
2Geological resources and environmental carrying capacity evaluation review,theory, and practice in China显示文摘Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict development in a region.In this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is studied.Then a 'coordination theory of resources and environmental carrying'is proposed.Next,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first time.This paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity evaluation.Finally,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods.Rui-min Li Zhi-qiang Yin Yi Wang Xiao-lei Li Qiong Liu Meng-meng Gao 2018China Geology2018,1,4:19
3大跨度钢桁架拱桥的极限承载力研究显示文摘在强地震设防区或桥梁承受铁路荷载且地质条件良好时,钢桁架拱桥是理想的大跨度桥梁选择方案。以朝天门大桥和大宁河大桥为背景,从边界条件、初始状态、荷载要素等几个关键影响参数着手,对大跨度钢桁架拱桥的极限承载能力进行参数研究,指出活载的布置形式、侧向风荷载及不同的约束条件对钢桁架拱桥的极限承载力有较大影响。方明霁 孙海涛 2010世界桥梁2010,38,4:14
4基于PS-DR-DP理论模型的区域资源环境承载力综合评价(英文)显示文摘The concepts of regional resources and environmental carrying capacity are important aspects of both academic inquiry and government policy. Although notable results have been achieved in terms of evaluating both these variables, most researchers have utilized a traditional analytical method that incorporates the 'pressure-state-response' model. A new approach is proposed in this study for the comprehensive evaluation of regional resources and environmental carrying capacity; applying a 'pressure-support', 'destructiveness-resilience', and 'degradation-promotion'('PS-DR-DP') hexagon interaction theoretical model, we divided carrying capacity into these three pairs of interactive forces which correspond with resource supporting ability, environmental capacity, and risk-disaster resisting ability, respectively. Negative carrying capacity load in this context was defined to include pressure, destructiveness, and degradation, while support, resilience, and promotion comprised positive attributes. The status of regional carrying capacity was then determined via the ratio between positive and negative contribution values, expressed in terms of changes in both hexagonal shape and area that result from interactive forces. In order to test our 'PS-DR-DP' theory-based model, we carried out a further empirical study on Beijing over the period between 2010 and 2015. Analytical results also revealed that the city is now close to attaining a perfect state for both resources and environmental carrying capacity; the latter state in Beijing increased from 1.0143 to 1.1411 between 2010 and 2015, an improved carrying capacity despite the fact that population increased by two million. The average contribution value also reached 0.7025 in 2015, indicating that the city approached an optimal loading threshold at this time but still had space for additional carrying capacity. The findings of our analysis provide theoretical support to enable the city of Beijing to control population levels below 23 million by 2020.王亮 刘慧 2019Journal of Geographical Sciences2019,29,3:11
5群岛阻滞效应影响舟山群岛水流挟沙力空间变化研究显示文摘在舟山群岛海域大范围实测资料的基础上,通过分析指出舟山群岛海域的含沙量空间分布具有明显的东南方向低、西北方向高的特点。同时,利用平面二维潮流及波浪数学模型模拟该海域的潮流场和波浪场,在此基础上对比刘家驹、窦国仁公式、不分区及分区拟合的挟沙力公式的计算结果与实测含沙量的差异,提出群岛水域只有分区计算才能从整体上把握挟沙力的空间分布特性,并从波浪及潮流的角度分析群岛水域水动力条件的变化,提出是群岛的阻滞效应导致了挟沙力空间分布的不均匀性。此外,对刘家驹及窦国仁公式的适应性进行了初步探讨,提出在舟山群岛水域,刘家驹公式中系数0.0273修正为0.13后能获得较为合理的计算结果。黄惠明 王义刚 王乐乐 夏雪瑾 2010泥沙研究2010,35,6:7
6Performance Evaluation of Urban Comprehensive Carrying Capacity of Harbin, Heilongjiang Province in China显示文摘Urban comprehensive carrying capacity is an important guarantee and external representation of regional sustainable development. Based on urban comprehensive carrying capacity, this paper constructed a performance evaluation index system of urban comprehensive carrying capacity, and used entropy method, urban comprehensive carrying capacity measurement model and urban sustainable development model to measure spatial and temporal comprehensive carrying capacity of Harbin City in Heilongjiang Province from 2012 to 2017. The results show that: 1) index weight analysis suggested the regional development mode in Harbin still followed an epitaxial development mode, which pursued the expansion of scale and the growth of total amount of regional development, neglecting the effective utilization of resources and the improvement of structural benefits. 2) In the pressure system, the index of resource support has dropped sharply. The index of environmental capacity and social progress has risen circuitously, while the degree of agglomeration and the value of transportation facilities have risen steadily;in the pressure system, the index of population development and economic growth tended to fluctuate, while energy consumption and environmental pollution showed a more synchronous change in characteristics, and the livable demand remained at a high level. 3) The carrying capacity index of resources and environment in Harbin has been declining, and the acquired carrying capacity index fluctuated. The long-term regional development model has severely impaired the carrying capacity of resources and environment. 4) The comprehensive carrying capacity of Harbin has clear spatial differentiation characteristics. Finally, the paper proposes that location conditions, economic development level, government regulation, and science and technology are the main factors influencing the spatial differentiation of urban comprehensive carrying capacity.DIAO Shuo YUAN Jiadong WU Yanyan 2019Chinese Geographical Science2019,29,4:6
7Regional carrying capacity: case studies of Bohai Rim area显示文摘Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rims sustainable development. Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.Yu Dan-lin Mao Han-ying 2002Journal of Geographical Sciences2002,12,2:4
8Carrying capacity for the electromagnetic suspension low-speed maglev train on the horizontal curve显示文摘Aiming at the lateral dislocation between the electromagnets and the rails on a horizontal curve,we investigated a single magnetic bogie of the maglev train in this paper.The magnetic levitation and guidance forces supplied by the suspension modules were deduced by the flux tube method.According to the dynamic equilibrium equations of the maglev train on the curved track with cant,several major factors that influence the carrying capacity were analyzed,and the formula of the carrying capacity was presented.The results provide a theoretical reference for the design of maglev train.CUI Peng,LI Jie & LIU DeSheng Maglev Engineering Center,National University of Defense Technology,Changsha 410073,China 2010Science China(Technological Sciences)2010,53,4:4
9Quantitative evaluation of Tibet’s resource and environmental carrying capacity显示文摘This study identifies the carrying state and value of Tibet’s resource and environmental carrying capacity.A new theoretical framework is proposed for exploring the resource and environmental carrying capacity based on two perspectives of“growth limit”and“stability of Human-Earth relationship system”.On this basis,an ideal growth model that accords with the“short board”effect is established to predict the population limitation.Analytical results show that the holistic state of resource and environmental carrying capacity in Tibet is in jeopardy.From 2010 to 2016,Tibet’s carrying state continued to decline,moreover,the negative forces still overwhelm the positive forces.Although the resource reserves still have room for more population,the environmental capacity and ecological capacity have been overloaded.Meanwhile,the Human-Earth relationship system is in an unstable stage.Three scenarios that respond to different socioeconomic developments are implemented to predict the population limitation of resource and environmental carrying capacity in Tibet;thus,authors argue that Tibet should keep its population size within 4 million around 2025.This research will provide reference for sustainable development and resources and environmental conservation in Tibet.WANG Liang LIU Hui 2019Journal of Mountain Science2019,16,7:4
10Carrying Capacity of Water Leisure Environment in Eco-cities-A Case Study of Ancient Canal Scenic Area in Yangzhou City显示文摘Water leisure tourism is an emerging theme in urban planning, and its planning mode and operation level directly influence the eco-cycle degree of urban development. Tourism activities inevitably impact environmental quality of urban water spaces, and the research on the environmental carrying capacity of such spaces has also become an important prerequisite of tourism planning. Taking the Yangzhou Ancient Canal Scenic Area for an example, the paper constructed the estimated indicators of water leisure tourism environmental carrying capacity on the basis of analyzing scenic geographical resources and tourism economic conditions, and calculated the scenic area's water leisure tourism environmental integrated carrying capacity by the method of barrel extrapolation, providing a reasonable foundation for evaluating the planning conditions in the eco-cycle urban water leisure tourism planning.SONG Li XIAO Ping 2013Journal of Landscape Research2013,5,4:4
11Risk-based evaluation on geological environment carrying capacity of mountain city - A case study in Suide County, Shaanxi Province, China显示文摘With the rapid development and expansion of the cities in China, the carrying capacity of resource and environment has become a huge concern for local governments. From the perspective of geological environment, geological disasters are the main restraining factor of the development in mountain cities. This study was conducted in Suide County of Shaanxi Province with a risk-based approach as followed: a hazard analysis on geological disasters based on a slope geological survey at a scale of 1:10,000; a consequence analysis based on unmanned aerial vehicle(UAV) aerial survey data; integrating the results of hazard analysis and consequence analysis, a risk zonation and analysis of geological disasters in urban areas were completed considering urban planning, land use planning and the safety of infrastructure and major engineering. Subsequently, taking the acceptable levels of human life and property risks incurred by landslides as the criteria of the evaluation of geological environment carrying capacity, a comprehensive assessment of current and future urban carrying capacity was conducted based on the results of the risk analyses. Accordingly, the prior development zone, the restricted development zone and the prohibited zone were delineated, with corresponding suggestions for future urban development. The technological and methodological system used in the study can be applied to geological environment carrying capacity evaluation of other important mountain cities, which can provide scientific basis for the optimization of land and space.WANGYao ZHANG Mao-sheng XUE Qiang WU Si-duo 2018Journal of Mountain Science2018,15,12:4
12A Vesicular Stomatitis Virus-Based Vaccine Carrying Zika Virus Capsid Protein Protects Mice from Viral Infection显示文摘Dear Editor,Zika virus (ZIKV) is a mosquito-borne virus that belongs to the Flavivirus family along with dengue virus (DENV),yellow fever virus, West Nile virus, and Japanese encephalitis virus (Ming et al. 2016). ZIKV is a singlestranded positive-sense RNA virus encoding three structural proteins, including nucleocapsid protein C, prM/M,envelope glycoprotein E, and seven non-structural proteins.Since 2015.Xiaodan Shi Jingping Hu Jing Guo Chuanjian Wu Sidong Xiong Chunsheng Dong 2019Virologica Sinica2019,34,1:2
13Dynamic Change of Ecological Footprint in Xingtai City in the Years 2003-2009显示文摘Quantitative estimation of the ecological footprint in Xingtai City in the years 2003-2009 is carried out by using the Ecological Footprint Model and the Time Series.Result shows that the per capita ecological footprint demand increases in Xingtai City from the year 2003 to 2009;and land use for energy shows a significant increase,accounting for the maximum proportion in per capita ecological footprint demand.Per capita ecological footprint supply gradually decreases.Ecological supply provided by cultivated land occupies the greatest proportion in the supply of per capita ecological carrying capacity,which is the main factor determining the supply of ecological carrying capacity in Xingtai City.In the years 2003-2009,ecological footprint of Xingtai City is at the state of ecological deficit.This indicates that the economic and social development of Xingtai City is based on the over-exploitation of resources,especially the cultivated land and energy land.Thus,the development mode of Xingtai City has already been in a state of unsustainable development.Based on this,corresponding countermeasures are put forward for the sustainable development in future,so as to implement the healthy control of the sustainable development in Xingtai City,China.CHEN Ji-bing,LI Yu-ping Department of Geography,Xingtai University,Xingtai 054001,China 2011Asian Agricultural Research2011,3,2:2
14Comprehensive Assessment of Water Environment Carrying Capacity of Yunnan Province显示文摘Based on the concept and connotation of water environment carrying capacity, taking Yunnan Province as a case, this paper built water environment carrying capacity evaluation system from the perspectives of water resources, water environment carrying capacity and socio-economic development, and applied the index evaluation model to analyze the trends of water environment carrying capacity in Yunnan from 2006 to 2014. The results showed that, during those years, the evaluation value of water environment carrying capacity ranged from 0.23 to 0.46 in Yunnan Province.The minimum value was 0.23 in 2013, the maximum value was 0.46 in 2010. From 2006 to 2014, the evaluation value of water environment carrying capacity was less than 0.5 in general, and the water environment in a fragile state on the whole.DONG Xuyan LU Ying ZHOU Zixuan CHEN Hao 2017Journal of Landscape Research2017,9,3:2
15Spatio-temporal Change and Carrying Capacity Evaluation of Human Coastal Utilization in Liaodong Bay,China from 1993 to 2015显示文摘In China, promoting the development of coastal areas has been included in a series of national strategic development plans.At the same time, many marine environmental problems have been associated with the rapid development of coastal sea use. In order to quantify the impact of human activities on the coast, the characteristics of coastlines and near-shore sea use of Liaodong Bay, Northeast China, were first classified using multi-source, remotely sensed imagery using automatic or semi-automatic extraction methods for five periods between 1993 and 2015. Sea use dynamics and coastline dynamics resulting from human activates were analyzed. Results showed a significant trend of continuous growth in sea use and a progressive increase in the total length of artificial coastline, but a noticeable loss of natural coastline during the five periods. Reclaimed land and enclosed areas were the main types of sea use. Most coastal human activities were distributed in the northern part of the bay. In recent years, rapid industrialization and urbanization in China's coastal areas have promoted large-scale land reclamation. Accordingly, the observed coastline changes during each period had a close relationship with coastal development and sea area utilization. Based on marine functional zoning(MFZ), the sea use carrying capacity was evaluated by means of indexes to describe human exploitation of the marine and coastal environments in the bay. This showed that the intensity of coastal utilization in Liaodong Bay has increased year-on-year. Sea use carrying capacity reached a ‘critically loaded'state by 2008 and was ‘overloaded' by 2015.XU Jingping LI Fang SUO Anning ZHAO Jianhua SU Xiu 2019Chinese Geographical Science2019,29,3:2
16广西北部湾经济区水资源可利用量及承载能力研究显示文摘通过分析广西北部湾经济区水资源开发状况、可利用量以及人类生存与发展对水资源的需求,采用最大可承载人口数量方法,评估了该地区不同水平年水资源在合理和极限两种开发利用状态下的人口承载量。计算结果表明,在合理开发利用状态下,经济区将在2030年出现人口超载77.83万人,而水资源本底条件较差的北海市在2005年~2030年人口超载20万~160万人;在极限开发利用状态下,只有北海市在2010年~2030年人口超载17万~110万人。建议采取跨流域调水、雨洪资源利用等措施,以满足广西北部湾经济区经济社会的可持续发展对水资源的需求。莫崇勋 蔡德所 杜群超 孙桂凯 2010水力发电2010,36,11:2
17The suspended sediment transport equation and its near-bed sediment flux显示文摘The suspended sediment transport equation and its near-bed sediment flux are one of the key problems of sediment transport research under nonequilibrium condition. Based on the three-dimensional primitive suspended transport equation, the two-dimensional suspended sediment transport equation is deduced. The derived process indicates that the physical essence of the near-bed sediment flux is right the bottom boundary condition for the suspended sediment transport equation. This paper analyzes the internal relations between the two methods of sediment carrying capacity and shear stress in common use, points out the consistency of these two methods in terms of form and physical meaning, and unifies these two methods theoretically. Furthermore, based on the analysis and comparison of the expressions of the near-bed sediment flux, this paper summarizes some problems to which attention should be paid, thus offering a novel approach to the study and the solution of the problems of suspended sediment transport and exchange flux of near-bed water sediment.LI RuiJie1,2, LUO Feng2 & ZHU WenJin3 1 Key Laboratory of Coastal Disaster and Defence (Hohai University), Ministry of Education, Nanjing 210098, China 2 Laboratory of Marine Environment, Hohai University, Nanjing 210098, China 3 Institute of Physical Oceanography, Hohai University, Nanjing 210098, China 2009Science China(Technological Sciences)2009,52,2:2
18教育目标分类学提纲 动作技能领域(三)显示文摘3.00 运动活动(Motor activity) 3.10 进行工作的身体定势(Bodily set to perform task)(定位)(positioning) 3.11 姿势(Posture) 3.12 平衡(Balance) 3.13 对准目标(Aiming) 3.20 大运动能力(Gross motor abilities) 3.21 包括躯体的运动(Movement1987华东师范大学学报(教育科学版)1987,5,1:1
19Adding body load modifies the vibratory sensation of the foot sole and affects the postural control显示文摘Background: Heavy backpacks are often used by soldiers and firefighters. Weight carrying could reduce the speed and efficiency in task completion by altering the foot sole sensitivity and postural control.Methods: In fifteen healthy subjects, we measured the changes in sensitivity to vibrations applied to the foot sole when standing upright or walking after load carrying(30% body weight). The participants were asked to judge different vibration amplitudes applied on the 2 nd or 5 th metatarsal head and the heel at two frequencies(25 and 150 Hz) to determine the vibration threshold and the global perceptual representation(Ψ)of the vibration amplitude(Φ)given by the Stevens power function(Ψ=k×Φ~n). Any increase in negative k value indicated a reduction in sensitivity to the lowest loads. Pedobarographic measurements, with computation of the center of pressure(COP) and its deviations, were performed during weight carrying.Results: The 25-Hz vibration threshold significantly increased after weight carrying when standing upright or walking.After standing with the added loads, the absolute negative k value increased for the 25 Hz frequency. After walking with the added loads, the k coefficient increased for the two vibration frequencies. Weight carrying significantly increased both the CoP surface and CoP lateral deviation.Conclusions: Our data show that weight carrying reduces the sensory pathways from the foot sole and accentuates the center of pressure deviations.Yves Jammes Eva Ferrand Corentin Fraud Alain Boussuges Jean Paul Weber 2019Military Medical Research2019,6,1:1
20Magnetic fluid based squeeze film between porous circular disks with sealed boundary显示文摘Efforts have been made to study the effect of the magnetic fluid lubricant and the seal-ing of the boundary for the squeeze film between two circular disks when the upper disk having aporous facing with its boundary sealed, approaches the non-porous lower disk normally. The modi-fied Reynolds equations for the fluid region and the governing Laplacian equation for the pressurein porous region are solved with appropriate boundary conditions. Expressions are obtained forpressure, load carrying capacity and the response time. The results are presented graphically. Thecombined effect of the magnetic fluid lubricant and sealing of the boundary increases the load car-rying capacity significantly and hence the performance of the bearing can be enhanced considera-bly by sealing the boundary and taking a magnetic fluid as lubricant.R.M.PATEL G.M.DEHERI 2001Science China Mathematics2001,44,S1:1
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