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一种基于Hop-Along的遥感图像道路提取算法 被引量:3
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作者 夏静 胡茂林 卜华龙 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第12期1938-1940,1952,共4页
基于数值形态学的道路提取是遥感图像处理的常见问题,通常结构元素的选取复杂多变,降低了算法的自动化程度。文章结合数值形态学和Hop-Along算法,对影像进行预处理、阈值分割,得到包含道路信息的二值影像;使用数值形态学的腐蚀运算及形... 基于数值形态学的道路提取是遥感图像处理的常见问题,通常结构元素的选取复杂多变,降低了算法的自动化程度。文章结合数值形态学和Hop-Along算法,对影像进行预处理、阈值分割,得到包含道路信息的二值影像;使用数值形态学的腐蚀运算及形态重建,得到主要道路网络;使用局部Hop-Along算法进行多线拟合,得到单像素的道路中心线。通过对高分辨率遥感图像的Matlab实验证明,算法大幅降低了选取结构元素的次数,提高了自动化程度,且保持了数值形态学的几何学特性。 展开更多
关键词 道路提取 数值形态学 局部Hop-along算法
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Research on the Harmony between Route Design of and Landscapes along Highway 被引量:1
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作者 汤振兴 朱晓娟 《Journal of Landscape Research》 2010年第11期15-19,23,共6页
Through analyzing landscape environment which is the principal factor to be considered in the route design of highway,principles to be followed by the highway route design are proposed,and approaches of maintaining th... Through analyzing landscape environment which is the principal factor to be considered in the route design of highway,principles to be followed by the highway route design are proposed,and approaches of maintaining the harmony between route design and landscape along the highway under different conditions are discussed. 展开更多
关键词 HIGHWAY ROUTE design Landscapes along the HIGHWAY HARMONY
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Formation mechanism of propagated sensation along the meridians,as verified by cortical somatosensory-evoked potential topographic maps 被引量:3
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作者 Jinsen Xu Xiaohua Pan Shuxia Zheng Xianglong Hu Zheyan Sa 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第6期435-439,共5页
The peripheral driver stimulating theory states that as a driver passes along a certain meridian during acupuncture; the driver provokes nerve sense devices along the meridian, resulting in the nerve impulse entering ... The peripheral driver stimulating theory states that as a driver passes along a certain meridian during acupuncture; the driver provokes nerve sense devices along the meridian, resulting in the nerve impulse entering the central nervous system. Accordingly, volunteers have reported propagated sensations along the meridians (PSM). The present study was designed to utilize a cortical somatosensory-evoked potential (CSEP) topographic map for determining whether stimulation expansion occurs in somatosensory area I when sensation was provoked in individuals with obvious PSM. The sensation was blocked by mechanical compression, and the sensation was imitated in individuals without PSM. Results revealed a red, high-potential signal in the representative area of the lower limbs in individuals with obvious PSM symptoms when the Gall Bladder Meridian (GBM) sensation passed to the head and face. This representative area was near the middle line of the CSEP topographic map, and a red, high-potential signal, which jumps over the representative area of the upper limbs, also appeared in the representative face area, which was at the external region of the CSEP topographic map. However, in individuals exhibiting no PSM, only a red high-potential signal appeared in the representative lower limb area. When Hegu (LI 4) was stimulated in individuals without PSM, an obvious evoked response appeared only in the representative upper limb area. However, when Hegu was stimulated in individuals exhibiting PSM, the response area was larger in the representative upper limb area and extended to the representative face area. When Guangrning (GB 37) was stimulated in PSM individuals, the face representation response disappeared and was confined to a foot representation of the somatosensory area I when PSM was blocked by mechanical pressure. Results suggested that mechanical compression blocked PSM, and corresponding changes were exhibited in the CSEP topographic map. These results provide compelling evidence for the hypothesis that peripheral driver stimulation is the key element in producing PSM. 展开更多
关键词 propagated sensation along the meridians MERIDIAN cortical somatosensoryevoked potential evoked potential topographic map
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Assimilating the along-track sea level anomaly into the regional ocean modeling system using the ensemble optimal interpolation 被引量:4
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作者 LYU Guokun WANG Hui +3 位作者 ZHU Jiang WANG Dakui XIE Jiping LIU Guimei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第7期72-82,共11页
The ensemble optimal interpolation (EnOI) is applied to the regional ocean modeling system (ROMS) with the ability to assimilate the along-track sea level anomaly (TSLA). This system is tested with an eddy-resol... The ensemble optimal interpolation (EnOI) is applied to the regional ocean modeling system (ROMS) with the ability to assimilate the along-track sea level anomaly (TSLA). This system is tested with an eddy-resolving system of the South China Sea (SCS). Background errors are derived from a running seasonal ensemble to account for the seasonal variability within the SCS. A fifth-order localization function with a 250 km localization radius is chosen to reduce the negative effects of sampling errors. The data assimilation system is tested from January 2004 to December 2006. The results show that the root mean square deviation (RMSD) of the sea level anomaly decreased from 10.57 to 6.70 cm, which represents a 36.6% reduction of error. The data assimilation reduces error for temperature within the upper 800 m and for salinity within the upper 200 m, although error degrades slightly at deeper depths. Surface currents are in better agreement with trajectories of surface drifters after data assimilation. The variance of sea level improves significantly in terms of both the amplitude and position of the strong and weak variance regions after assimilating TSLA. Results with AGE error (AGE) perform better than no AGE error (NoAGE) when considering the improvements of the temperature and the salinity. Furthermore, reasons for the extremely strong variability in the northern SCS in high resolution models are investigated. The results demonstrate that the strong variability of sea level in the high resolution model is caused by an extremely strong Kuroshio intrusion. Therefore, it is demonstrated that it is necessary to assimilate the TSLA in order to better simulate the SCS with high resolution models. 展开更多
关键词 ensemble optimal interpolation regional ocean modeling system along-track sea level anomaly South China Sea variability
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Adaptation strategy for sea level rise in vulnerable areasalong China's coast 被引量:3
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作者 Du Bilan, Zhang Jinwen (China Institute of Marine Affairs, State Oceanic Administration, Beijing 100860, China National Marine Data and Information Service, Tianjin 300171, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2000年第4期1-16,共16页
It can be seen from the calculation that the vulnerable area along China's coast in which the elevation is less than 5 m, is 143 900 km2, accounting for about 11. 3% of the total area of the 11 coastal provinces, ... It can be seen from the calculation that the vulnerable area along China's coast in which the elevation is less than 5 m, is 143 900 km2, accounting for about 11. 3% of the total area of the 11 coastal provinces, municipalities and autonomous regions. These areas are threatened to varying extent by sea level rise. According to prediction, the relative sea level rise (including global sea level rise caused by climate change and local relative as level rise caused by vertical crust movement and ground subsidence) along China's coast will be 4~16 cm by the year 2030 with the optimum estimated value of 6~14cm. It will be 9~26 cm by the year 2050 with the optimum estimated value of 12-23 cm. And it will be 31-74 cm by the year 2100 with the optimum estimated value of 47~65 cm. The calcuation result shows that the percentage of the cost for up-grading (heightening and consolidating) sea dykes/walls in adaptation strategy in the losses of submerged areas varies from area to area: 6. 9% in the Zhujiang (Pearl) River Deta, 1. 3% ~24. 6% in the Changjiang (Yangtze) River Delta, and 0. 9%~2. 0% in the Huanghe River Delta. 展开更多
关键词 Adaptation strategy for sea level rise vulnerable areas along China's coast submerged areas
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Physical analysis on improving the recovery accuracy of the Earth's gravity field by a combination of satellite observations in along-track and cross-track directions 被引量:4
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作者 郑伟 许厚泽 +1 位作者 钟敏 员美娟 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期633-640,共8页
The physical investigations on the accuracy improvement to the measurement of the Earth's gravity field recovery are carried out based on the next-generation Pendulum-A/B out-of-plane twin-satellite formation in this... The physical investigations on the accuracy improvement to the measurement of the Earth's gravity field recovery are carried out based on the next-generation Pendulum-A/B out-of-plane twin-satellite formation in this paper. Firstly, the Earth's gravity field complete up to degree and order 100 is, respectively, recovered by the collinear and pendulum satellite formations using the orbital parameters of the satellite and the matching accuracies of key payloads from the twin GRACE satellites. The research results show that the accuracy of the Earth's gravity field model from the Pendulum-A/B satellite formation is about two times higher than from the collinear satellite formation, and the further improvement of the determination accuracy of the Earth's gravity field model is feasible by the next-generation Pendulum-A/B out-of-plane twin-satellite formation. Secondly, the Earth's gravity field from Pendulum-A/B complete up to degree and order 100 is accurately recovered based on the orbital parameters of the satellite (e.g., an orbital altitude of 400 km, an intersatellite range of 100 km, an orbital inclination of 89° and an orbital eccentricity of 0.001), the matching accuracies of space- borne instruments (e.g. 10-6 m in the intersatellite range, 10-3 m in the orbital position, 10-6 m/s in orbital velocity, and 10-11 m/s2 in non-conservative force), an observation time of 30 days and a sampling interval of 10 s. The measurement accuracy of the Earth's gravity field from the next-generation Pendulum-A/B out-of-plane twin-satellite formation is full of promise for being improved by about l0 times compared with that from the current GRACE satellite formation. Finally, the physical requirements for the next-generation Pendulum-A/B out-of-plane twin-satellite formation are analyzed, and it is proposed that the satellite orbital altitude be preferably designed to be close to 400±50 km and the matching precision of key sensors from the Pendulum-A/B mission be about one order of magnitude higher than from the GRACE program. 展开更多
关键词 twin pendulum-MB satellites collinear and pendulum satellite formations along-cross-track ob-servations physical analysis satellite gravity recovery
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A new framework for evaluating along-wind responses of a transmission tower 被引量:3
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作者 Liu Guohuan and Li Hongnan School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116023, China PhD Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2009年第1期87-93,共7页
In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized ... In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized force spectrum (GFS) model of the transmission tower is deduced; (2) an analytical model that includes the contributions of the higher modes is further derived as a rational algebraic formula to estimate the structural displacement response; and (3) a new approach, applying load with displacement (ALD) instead of force, to solve the internal force of transmission tower is given. Unlike conventional methods, the ALD method can avoid calculating equivalent static wind loads (ESWLs). Finally, a transmission tower structure is used as a numerical example to verify the feasibility and accuracy of the ALD method. 展开更多
关键词 along-wind-induced dynamic responses transmission tower generalized force spectrum equivalent static wind loads
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The existence of propagated sensation along the meridian proved by neuroelectrophysiology 被引量:7
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作者 Jinsen Xu Shuxia Zheng +2 位作者 Xiaohua Pan Xiaoxiang Zhu Xianglong Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第28期2633-2640,共8页
Propagated sensation along the meridian can occur when acupoints are stimulated by acupuncture or electrical impulses. In this study, participants with notable propagated sensation along the me- ridian were given elec... Propagated sensation along the meridian can occur when acupoints are stimulated by acupuncture or electrical impulses. In this study, participants with notable propagated sensation along the me- ridian were given electro-acupuncture at the Jianyu (LI15) acupoint of the large intestine meridian. When participants stated that the sensation reached the back of their hand, reguJar nervous system action discharge was examined using a physiological recording electrode placed on the superficial branch of the radial nerve. The topographical maps of brain-evoked potential in the primary cortical somatosensory area were also detected. When Guangming (GB37) acupoint in the lower limb and Hegu (LI4) acupoint in the upper limb were stimulated, subjects without propagated sensation along the meridian exhibited a high potential reaction in the corresponding area of the brain cortical somatosensory area. For subjects with a notable propagated sensation along the meridian, the re- action area was larger and extended into the face representative area. These electrophysiological measures directly prove the existence of propagated sensation along the meridian, and the periph- eral stimulated site is consistent with the corresponding primary cortical somatosensory area, which presents a high potential reaction. 展开更多
关键词 neural regeneration ELECTRO-ACUPUNCTURE propagated sensation along meridian expanding ofcentral excitation discharge of afferent nerve topographical mapping of brain-evoked potential peripheral nerve central nerve grants-supported paper NEUROREGENERATION
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Distribution Characteristics of High Temperature Damage and Its Influence on the Rice Yield in the Area along Huaihe River 被引量:3
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作者 FENG De-hua1,JIANG Yue-lin1,YANG Tai-ming2,CHEN Jin-hua2 1.College of Resources & Environment,Anhui Agricultural University,Hefei 230036,China 2.Anhui Meteorological Science Research Institute,Hefei 230031,China 《Meteorological and Environmental Research》 CAS 2011年第3期73-76,80,共5页
[Objective] The research aimed to study the distribution characteristics of high temperature damage and its influence on the rice yield in the area along Huaihe River.[Method] The meteorological data of 10 stations in... [Objective] The research aimed to study the distribution characteristics of high temperature damage and its influence on the rice yield in the area along Huaihe River.[Method] The meteorological data of 10 stations in the area along Huaihe River during 1965-2009 and the yield data of Anhui single-season middle rice during 1967-2006 were selected.The occurrence characteristic of summer high temperature weather and the intensity of high temperature damage in the area along Huaihe River were analyzed.Based on the previous high temperature damage index of rice,Changfeng County where was the typical rice planting zone in the area along Huaihe River was as the representation,and the yield damage loss rate risk of high temperature damage in Changfeng was analyzed by combining with the historical yield data.[Result] The high temperature weather in the area along Huaihe River frequently happened.The high temperature damage presented 'N' shape trend from west to east.The occurrence frequency of high temperature weather in Huainan and Bengbu where were in the middle area along Huaihe River was more and was less in Huoqiu and Shouxian where were near the south mountain area of Anhui.The occurrence time mainly focused from the middle and last dekads of July to the first dekad of August after the plum rain.At this time,it was the booting,heading and flowering periods of single-season middle rice,and the influence on the rice yield was obvious.The damage loss rate of single-season middle rice yield in Changfeng County along Huaihe River continued to increase as the increasing of high temperature damage duration.But the occurrence probability decreased.The intensity grade of high temperature damage disaster loss rate which happened frequently concentrated mainly in levels I and II.The longer the high temperature damage duration in the reproductive growth stage of rice was,the bigger the damage loss rate was.But the corresponding occurrence probability was small,and vice versa.[Conclusion] The research provided the reference for assessing the high temperature disaster risk. 展开更多
关键词 High temperature damage Distribution characteristic RICE Disaster loss rate Area along Huaihe River China
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An evaluation of sea surface height assimilation using along-track and gridded products based on the Regional Ocean Modeling System(ROMS) and the four-dimensional variational data assimilation 被引量:1
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作者 ZHOU Chaojie DING Xiaohua +2 位作者 ZHANG Jie YANG Jungang MA Qiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第9期50-58,共9页
Remote sensing products are significant in the data assimilation of an ocean model. Considering the resolution and space coverage of different remote sensing data, two types of sea surface height(SSH) product are em... Remote sensing products are significant in the data assimilation of an ocean model. Considering the resolution and space coverage of different remote sensing data, two types of sea surface height(SSH) product are employed in the assimilation, including the gridded products from AVISO and the original along-track observations used in the generation. To explore their impact on the assimilation results, an experiment focus on the South China Sea(SCS) is conducted based on the Regional Ocean Modeling System(ROMS) and the four-dimensional variational data assimilation(4 DVAR) technology. The comparison with EN4 data set and Argo profile indicates that, the along-track SSH assimilation result presents to be more accurate than the gridded SSH assimilation, because some noises may have been introduced in the merging process. Moreover, the mesoscale eddy detection capability of the assimilation results is analyzed by a vector geometry–based algorithm. It is verified that, the assimilation of the gridded SSH shows superiority in describing the eddy's characteristics, since the complete structure of the ocean surface has been reconstructed by the original data merging. 展开更多
关键词 ROMS 4DVAR sea surface height assimilation along-track gridded product
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Quantitative Estimation of Air Mass Exchange by Along-Valley Wind in the Rongbuk Valley 被引量:1
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作者 Zhou Li-Bo Zou Han +3 位作者 Ma Shu-Po Zhu Jin-Huan Li Peng Huo Cui-Ping 《Atmospheric and Oceanic Science Letters》 2009年第1期29-34,共6页
For a better understanding of the air mass exchange processes between the surface and free atmos-phere in the Himalayas,a Himalayan exchange between the surface and troposphere 2007 (HEST2007) campaign was carried out... For a better understanding of the air mass exchange processes between the surface and free atmos-phere in the Himalayas,a Himalayan exchange between the surface and troposphere 2007 (HEST2007) campaign was carried out in the Rongbuk Valley,on the northern slope of Mt.Qomolangma,in June 2007.The wind,tem-perature and radiation conditions were measured during the campaign.Using these observation data,together with the National Centers for Environmental Prediction/the National Center for Atmospheric Research (NCEP/NCAR) reanalysis data,the air mass exchange between the inside of the valley and the outside of the valley is quantitatively estimated,based on a closed-valley method.The air mass is strongly injected into the Rongbuk Valley in the after-noon,which dominates the diurnal cycle,by a strong downward along-valley wind,with a maximum down-ward transfer rate of 9.4 cm s?1.The total air volume flux injected into the valley was 2.6×1011 m3 d?1 in 24 hours in June 2007,which is 15 times the total volume of the val-ley.The air mass transfer into the valley also exhibited a clear daily variation during the HEST2007 campaign,which can be affected by the synoptic situations through the adjustment of local radiation conditions. 展开更多
关键词 air mass exchange quantitative estimation along-valley wind the Himalayas
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Spatial-temporal Patterns of Land-use Change in Typical Transect Area Along China National Highway 106 During 1996-2008
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作者 LIU Yu LIU Yansui +1 位作者 GUO Liying LU Shasha 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第3期39-46,共8页
Based on land-use database updated with the survey of 1996, 2000, 2004 and 2008, this paper analyzed the land-use changes in the typical transect area along National Highway 106 with the aid of GIS technology and quan... Based on land-use database updated with the survey of 1996, 2000, 2004 and 2008, this paper analyzed the land-use changes in the typical transect area along National Highway 106 with the aid of GIS technology and quantitative models. The results showed that arable land had been continuously decreased from 1996 to 2008, with a loss of 65.85× 10^3 hm2 and an average decrement of 5.49×10^3 hm^2 per year, and the loss in northern areas was larger; garden land and woodland were gradually centralized to the predominance area with an increment of 25.73×10^3 hm2 and 22.37×10^3 hm2, respectively; residential and industrial land increased year after year, and the transportation land showed the equalized developing spatial pattern; the increment of construction land and encroachment on arable land in the area were deeply influenced by the national macroscopic land-use policies, the rapid advance of urbanization and the development level of the regional economy. Through this case study, it is suggested that differential land- use policies should be adopted to create good environmental conditions to guarantee food security and to promote the economic development. 展开更多
关键词 land-use change mechanism analysis transect area along China National Highway 106
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Rules for Access of Foreign Capitals to Agricultural Field in Countries along the "Belt and Road"
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作者 Haitao TANG 《Asian Agricultural Research》 2018年第1期37-39,50,共4页
Agriculture is related to the strategy and security of a country. Every country is very discreet about access of foreign capitals to the agricultural field. Countries along the " Belt and Road" also have imp... Agriculture is related to the strategy and security of a country. Every country is very discreet about access of foreign capitals to the agricultural field. Countries along the " Belt and Road" also have imposed restrictions on the access of foreign capitals to the agricultural field.There are restrictions on establishing agriculture-related enterprises,affiliated organizations,and branch offices. Also,there are regulations concerning the scope,proportion,performance requirement,and approval of access of foreign capitals to the agricultural field. 展开更多
关键词 Countries along the "Belt and Road" Agriculture Access of foreign capitals Regulations
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Application Research of Gravel and Machine-Made Sand along the KKH-2 Project in Pakistan on Asphalt Pavement
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作者 Jun Hu Xiao Tian +1 位作者 Gang Wang Zhiqiang Wang 《World Journal of Engineering and Technology》 2019年第4期622-633,共12页
According to the characteristics of stone along the KKH-2 project in Pakistan, the applicability of gravel and machine-made sand for road engineering was studied. Through investigation, the types of stone along the pr... According to the characteristics of stone along the KKH-2 project in Pakistan, the applicability of gravel and machine-made sand for road engineering was studied. Through investigation, the types of stone along the project were relatively simple, and the stone materials used for road construction were mainly limestone, sandstone and pebbles, and the reserves?were?abundant. The experiment research and analyses comparisons of the parameters and road performance characteristics of natural gravel materials were carried out, and the design parameters and road performance indicators of natural grit in the current code were supplemented and adjusted to make it more suitable for Pakistan to use natural gravel materials for road construction. Thesis combines the project,?proposing that mechanism sand and natural sand mixed concrete?is?not inferior?tonatural sand mixed concrete in terms of technical performance, and the overall cost is lower than that of natural sand mixed concrete. The research results are of great significance for saving engineering construction costs, ensuring road performance and prolonging service life. 展开更多
关键词 Pakistan KKH-2 PROJECT STONE along the Line Machine-Made SAND Concrete Experimental Research
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The Belt and Road Initiative and the Concept of an Economic Corridor along the Southern Silk Road
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作者 Lin Wenxun Wu Lingwei 《Contemporary Social Sciences》 2017年第4期24-33,共10页
The Belt and Road Initiative requires the urgent revival of the Southern Silk Road. This means a good understanding of its rich historical connotations and its comprehensive and mutual-beneficial functions. Starting f... The Belt and Road Initiative requires the urgent revival of the Southern Silk Road. This means a good understanding of its rich historical connotations and its comprehensive and mutual-beneficial functions. Starting from a very early period, the Southern Silk Road has played an important role in the history of Yunnan and has been characterized by using cowry as money. This paper proposes the development of a new economic corridor along the Southern Silk Road from Xi'an in the north, via Chengdu and Kunming, to South Asia and Southeast Asia thus linking the Silk Road Economic Belt to the 21 st Century Maritime Silk Road. This will bring about a new phase of all-around opening-up linking domestic and overseas markets via land and sea. 展开更多
关键词 The Belt and Road Initiative the economic corridor along the Southern Silk Road the role of Yunnan the concept
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Using Tangent Boost along a Worldline and Its Associated Matrix in the Lie Algebra of the Lorentz Group
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作者 Michel Langlois Martin Meyer Jean-Marie Vigoureux 《Journal of Modern Physics》 2017年第8期1190-1212,共23页
In order to generalize the relativistic notion of boost to the case of non inertial particles and to general relativity, we look closer into the definition of the Lie group of Lorentz matrices and its Lie algebra and ... In order to generalize the relativistic notion of boost to the case of non inertial particles and to general relativity, we look closer into the definition of the Lie group of Lorentz matrices and its Lie algebra and we study how this group acts on the Minskowski space. We thus define the notion of tangent boost along a worldline. This very general notion gives a useful tool both in special relativity (for non inertial particles or/and for non rectilinear coordinates) and in general relativity. We also introduce a matrix of the Lie algebra which, together with the tangent boost, gives the whole dynamical description of the considered system (acceleration and Thomas rotation). After studying the properties of Lie algebra matrices and their reduced forms, we show that the Lie group of special Lorentz matrices has four one-parameter subgroups. These tools lead us to introduce the Thomas rotation in a quite general way. At the end of the paper, we present some examples using these tools and we consider the case of an electron rotating on a circular orbit around an atom nucleus. We then discuss the twin paradox and we show that when the one who made a journey into space in a high-speed rocket returns home, he is not only younger than the twin who stayed on Earth but he is also disorientated because his gyroscope has turned with respect to earth referential frame. 展开更多
关键词 LIE Group of Lorentz Matrices LIE Algebra TANGENT BOOST along a Worldline Acceleration Special RELATIVITY General RELATIVITY Thomas Rotation Twin Paradox INERTIAL Particles Non INERTIAL Particles
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CHINA AND RUSSIA JOIN HANDS TO BUILD PIVOT PORTS ALONG SILK ROAD ON ICE
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作者 ZHANG TINGTING CHEN XIAOCHEN 《Contemporary World》 2018年第2期45-48,共4页
The "Ice Silk Road", ever since its proposal during the meeting between the Chinese and Russian foreign ministers in May 2017, has become an important area of bilateral cooperation. We believe that, in a broad sense... The "Ice Silk Road", ever since its proposal during the meeting between the Chinese and Russian foreign ministers in May 2017, has become an important area of bilateral cooperation. We believe that, in a broad sense, the "Ice Silk Road" refers to the economic cooperation with the Arctic states; and in a narrow sense, it refers to the Arctic shipping routes that connect East Asia, Western Europe and North America, especially the Arctic Northeast Passage. This article adopts the narrow definition. 展开更多
关键词 CHINA RUSSIA PIVOT PORTS along SILK ROAD ON ICE
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Exact Traveling Wave Solutions for Nano-Solitons of Ionic Waves Propagation along Microtubules in Living Cells and Nano-Ionic Currents of MTs
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作者 Emad H. M. Zahran 《World Journal of Nano Science and Engineering》 2015年第3期78-87,共10页
In this work, the extended Jacobian elliptic function expansion method is used as the first time to evaluate the exact traveling wave solutions of nonlinear evolution equations. The validity and reliability of the met... In this work, the extended Jacobian elliptic function expansion method is used as the first time to evaluate the exact traveling wave solutions of nonlinear evolution equations. The validity and reliability of the method are tested by its applications to nano-solitons of ionic waves propagation along microtubules in living cells and nano-ionic currents of MTs which play an important role in biology. 展开更多
关键词 Extended Jacobian Elliptic Function Expansion Method Nano-Solitons of IONIC WAVES PROPAGATION along MICROTUBULES in Living Cells Nano-Ionic Currents of MTS Traveling Wave Solutions
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The Actualities and Countermeasures of Soil Erosion along the Tanggula to Lhasa Section of the Qinghai-Tibet Railway
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作者 Du Bei 《工程科学(英文版)》 2006年第2期49-55,共7页
The ecological environment in the area where the Qinghai-Tibet Railway passes through is very fragile and is showing the tendency of retrogression. So as the construction would largely disturb the earth surface and ve... The ecological environment in the area where the Qinghai-Tibet Railway passes through is very fragile and is showing the tendency of retrogression. So as the construction would largely disturb the earth surface and vegetation and would have a large quantity of earth and stone digging, the construction of the railway in this area would certainly lead to a series of questions. Through the integrated analysis of the actualities of soil erosion and water and soil conservation along the section of Tanggula-Lhasa of the Qinghai-Tibet Railway, and with the combination of the features of the railway construction and the environment, the protection measures and proposals about the soil erosion along the section of Tanggula to Lhasa of the Qinghai-Tibet Railway have been put forward, so as to reach to the purpose of holding back the further development of soil erosion along the line, improving the ecological environment in the local area and maintaining the railway in normal operation. 展开更多
关键词 青藏铁路 唐古拉-拉萨地区 铁路沿线 土壤浸蚀 保护措施
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基于遥感监测的沿运洼地内涝特征与影响因素研究
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作者 王大勇 管清花 +4 位作者 金瑞清 刘丹 窦俊伟 陈学群 范明元 《灌溉排水学报》 CAS CSCD 2024年第6期99-105,112,共8页
【目的】探究沿运邳苍郯新平原洼地内涝特征及影响因素。【方法】以沿运洼地为重点研究区域,在内涝影响范围内开展勘测、遥感解译等,分析洪涝前后归一化差异水体指数(NDWI)及归一化植被指数(NDVI)特征,研究沿运邳苍郯新平原涝洼地内涝... 【目的】探究沿运邳苍郯新平原洼地内涝特征及影响因素。【方法】以沿运洼地为重点研究区域,在内涝影响范围内开展勘测、遥感解译等,分析洪涝前后归一化差异水体指数(NDWI)及归一化植被指数(NDVI)特征,研究沿运邳苍郯新平原涝洼地内涝影响范围变化及其对农作物长势影响,探索水利设施建设等对灾害范围的影响。【结果】(1)受灾作物2004年与2005年NDVI的差值为0.5,未受灾区域2004年与2005年NDVI差值为0.25,受灾作物NDVI显著降低,受灾区域内2005年整年作物生长情况弱于2004年。(2)台儿庄节制闸建成后可降低洪涝对附近农田的影响,有效减少洪涝灾害造成的经济损失。【结论】洪涝灾害对洼地内作物长势影响大于洼地外作物,水利设施建设可以有效减少洪涝灾害造成的经济损失;遥感监测技术是防治洪涝灾害的有效手段。 展开更多
关键词 沿运洼地 内涝特征 归一化差异水体指数 归一化植被指数 水利设施
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