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Mathematical Definitions of Point, Line and Area Symbols in Cartography 被引量:3
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作者 WEIWenzhan ZHONGYexun +1 位作者 PENGYueying ZHENGHongbo 《Geo-Spatial Information Science》 2003年第3期62-65,共4页
The line cartographic symbol located on the boundary and the point cartographic symbol located by single point are the main body and stress of the map. The cartographic symbols are divided into point, line and area sy... The line cartographic symbol located on the boundary and the point cartographic symbol located by single point are the main body and stress of the map. The cartographic symbols are divided into point, line and area symbol in cartography and traditional educational books, but up to now there is only qualitative description about the three kinds of symbols, there are not the mathematical definitions of point, line and area symbols. This paper tries to solve the problem. The authors propose the mathematical definition about point, line and area cartographic symbol according to the theory of topology and expound their dependence relation. 展开更多
关键词 point cartograrphic symbol line cartographic symbol area cartographicsymbol FIGURE
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Research on Monitoring Area Division of Quality Grade Changes in County Cultivated Land and Technology of Deploying Monitoring Point
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作者 Wei WEI Lijun LIAO Jianxin YU 《Asian Agricultural Research》 2013年第7期60-62,79,共4页
It is an important means in management of improving both the quality and quantity of cultivated land to monitor grade changes in cultivated land quality. How to deploy monitoring network system and its point reasonabl... It is an important means in management of improving both the quality and quantity of cultivated land to monitor grade changes in cultivated land quality. How to deploy monitoring network system and its point reasonably and roundly are the key to the technology of monitoring grade changes in cultivated land quality by monitoring grade changes in cultivated land quality dynamically in order to obtain the information to the index of cultivated land quality and its changes based on the existing achievements of farmland classification and grading. Spatial analysis method is used to demarcate monitoring area and deploy monitoring point according to ARCGIS,of which the result can meet the demand for monitoring grade changes in cultivated land. 展开更多
关键词 CULTIVATED LAND quality MONItoRING MONItoRING area
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Fractal Analysis on the Spatial Structure of Land Use Patterns in a Non-Point Source Polluted Area in Southern China
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作者 RONG Kun 《Journal of Landscape Research》 2019年第3期19-22,共4页
Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fract... Based on the TM remote sensing interpretation of land use data of a non-point source polluted area in southern China in 2015, supported by ArcGIS and the fractal theory, this paper established the perimeter-area fractal equation of the spatial structure of land use types, quantitatively calculated the fractal dimension and stability index of various land use types in this non-point source polluted area in 2015, and analyzed the spatial structure characteristics of land use types. The results showed that the fractal dimension values of the different land use types in the research area ranged 1.141–1.657, and the whole fractal dimension of the research area was 1.206. To be specific, the fractal dimension values of unused land, grass land and rural residential land were high, and the fractal dimension values of dry land, paddy filed and waters were low, and the fractal dimension values of urban land, industrial traffic construction land and forest land were moderate. The area of the land use types whose stability index values were 0.2–0.4 accounted for 89.5% of total area, suggesting that the stability of the spatial structure of land use types of Beibei District in 2015 was not high generally. The rural residential land and urban land of the research area should be planned and managed more properly from now on. 展开更多
关键词 LAND use type SPATIAL structure FRACTAL DIMENSION Stability INDEX Non-point source polluted area
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Acupuncture at Waiguan(SJ5) and sham points influences activation of functional brain areas of ischemic stroke patients: a functional magnetic resonance imaging study 被引量:22
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作者 Ji Qi Junqi Chen +5 位作者 Yong Huang Xinsheng Lai Chunzhi Tang Junjun Yang Hua Chen Shanshan Qu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第3期293-300,共8页
Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effect... Most studies addressing the specificity of meridians and acupuncture points have focused mainly on the different neural effects of acupuncture at different points in healthy individuals. This study examined the effects of acupuncture on brain function in a pathological context. Sixteen patients with ischemic stroke were randomly assigned to true point group (true acupuncture at right Waiguan (SJ5)) and sham point group (sham acupuncture). Results of functional magnetic resonance imaging revealed activation in right parietal lobe (Brodmann areas 7 and 19), the right temporal lobe (Brodmann area 39), the right limbic lobe (Brodmann area 23) and bilateral oc-cipital lobes (Brodmann area 18). Furthermore, inhibition of bilateral frontal lobes (Brodmann area 4, 6, and 45), right parietal lobe (Brodmann areas 1 and 5) and left temporal lobe (Brodmann area 21 ) were observed in the true point group. Activation in the precuneus of right parietal lobe (Brodmann area 7) and inhibition of the left superior frontal gyrus (Brodmann area 10) was observed in the sham group. Compared with sham acupuncture, acupuncture at Waiguan in stroke patients inhibited Brodmann area 5 on the healthy side. Results indicated that the altered specificity of sensation-associated cortex (Brodmann area 5) is possibly associated with a central mechanism of acupuncture at Waiguan for stroke patients. 展开更多
关键词 nerve regeneration ACUPUNCTURE Waiguan (SJS) brain injury ischemic stroke function-al magnetic resonance imaging Brodmann area sham point 973 Program neural regeneration
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Application of sequence stratigraphy to Triassic terrestrial strata in Tahe area of Tarim Basin 被引量:4
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作者 刘辰生 张琳婷 +1 位作者 郭建华 王明艳 《Journal of Central South University》 SCIE EI CAS 2012年第5期1388-1398,共11页
Based on a synthetic geological study of drilling,well logging and seismic data,core observations and geochemical analysis,it is recognized that Triassic sedimentary facies in the Tahe area of Tarim Basin include brai... Based on a synthetic geological study of drilling,well logging and seismic data,core observations and geochemical analysis,it is recognized that Triassic sedimentary facies in the Tahe area of Tarim Basin include braided river deposits filling erosional valleys,and sublacustrine fan,canyon and delta facies.Braided river deposits filling erosional valleys are dominated by coarse-grained lithic quartz sandstone with oblique bedding,and represent the most important sedimentation type of sandstone in the study area.Sublacustrine fan and canyon facies are mainly distributed in the Middle Oil Member.Most delta sediments are deposited in highstand system tract(HST),Because of frequent changes in base level,delta sediments are commonly eroded and rarely preserved.Sedimentary cycles are clearly reflected by lithology,sedimentary structures and well logging data,and are closely related to the changes in lacustrine level.In accordance with the basic principle of sequence subdivision,seven type-I boundaries can be recognized in Triassic strata and six type-I sequences are subdivided correspondingly.In general,lowstand system tract(LST) is well developed within stratigraphic sequences and forms the main body of reservoir sandstone in this area;highstand system tract(HST) and transgressive system tract(TST) are often eroded by upper sequences or missed,Although various factors have different influences on terrestrial sequence stratigraphy,the classical sequence stratigraphy theory proposed by VAIL can be applied to terrestrial strata. 展开更多
关键词 sequence stratigraphy erosional valley sublacustrine fan terrestrial sequence stratigraphy Tahe area Tarim Basin
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Control effects of the synsedimentary faults on the basin-marginal fans in the central part of the deep-water area of early Oligocene Qiongdongnan Basin, South China Sea 被引量:1
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作者 Guangzeng Song Zengxue Li +3 位作者 Haizhang Yang Dongdong Wang Ying Chen Rui Sun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2021年第2期54-64,共11页
The synsedimentary faults and basin-marginal fans located in the central part of the deep-water area of the early Oligocene Qiongdongnan Basin have been investigated using seismic profiles,boreholes,and well-log data.... The synsedimentary faults and basin-marginal fans located in the central part of the deep-water area of the early Oligocene Qiongdongnan Basin have been investigated using seismic profiles,boreholes,and well-log data.Through the formations of the characterized paleogeomorphology,such as transverse anticlines,fault ditches,and step-fault belts,the synsedimentary faults are known to have controlled the development position,distribution direction,and extension scales of the basin-marginal fans.For example,at the pitching ends of two adjacent faults,transverse anticlines developed,which controlled the development positions and distributions of the fans.During the early Oligocene,the faults controlled the subsidence center,and fault ditches were formed at the roots of the faults.In the surrounding salient or low salient areas,which were exposed as provenance areas during early Oligocene,the fault ditches acted as the source channels and determined the flow paths of the clastics,where incised valley fills were obviously developed.The fault ditches which developed in the sedimentary basins were able to capture the drainage systems and influenced the distributions of the fans.The large boundary faults and the secondary faults generated two fault terraces and formed step-fault belts.The first fault terrace caused the clastics to be unloaded.As a result,fans were formed at the entrance to the basin.Then,the second fault terrace caused the fans to move forward,with the fans developing in a larger extension scale.The results obtained in this study will potentially be beneficial in the future prospecting activities for reservoirs and coalmeasure source rocks in the basins located in the deep-water areas of the South China Sea. 展开更多
关键词 deep-water area synsedimentary fault basin-marginal fan transverse anticline fault ditch step-fault belt
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A method to determine the shell layout scheme for equipment battlefield damage tests under artillery fire 被引量:1
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作者 Cai Chen Quan Shi +2 位作者 Zhi-feng You Hong-yu Ge Fang Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2021年第2期682-691,共10页
In this paper,a new method for determining the shell layout scheme is proposed,which can make the equipment damage data by the battlefield damage test resemble as close as possible the actual combat data.This method i... In this paper,a new method for determining the shell layout scheme is proposed,which can make the equipment damage data by the battlefield damage test resemble as close as possible the actual combat data.This method is based on the analysis of the impact point distribution and effective damage area of equipment.In order to obtain the position of the impact points,an impact point distribution model under artillery fire was established.Similarly,in order to obtain the effective damage area of equipment,the concepts of generalized damage area and task-based equipment functional damage probability were demonstrated,and the corresponding calculation model was established.Through case analysis,the shell layout scheme was effectively obtained,verifying the correctness of the proposed method. 展开更多
关键词 Battlefield damage test Projectile impact point Effective damage area Functional damage
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Seismic sedimentology of conglomeratic sandbodies in lower third member of Shahejie Formation (Palaeogene) in Shengtuo area, East China 被引量:2
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作者 袁勇 张金亮 +2 位作者 李存磊 孟宁宁 李岩 《Journal of Central South University》 SCIE EI CAS 2014年第12期4630-4639,共10页
The sand-conglomerate fans are the major depositional systems in the lower third member of Shahejie Formation in Shengtuo area, which formed in the deep lacustrine environment characterized by steep slope gradient, ne... The sand-conglomerate fans are the major depositional systems in the lower third member of Shahejie Formation in Shengtuo area, which formed in the deep lacustrine environment characterized by steep slope gradient, near sources and intensive tectonic activity. This work was focused on the sedimentary feature of the glutenite segment to conduct the seismic sedimentology research. The near-shore subaqueous fans and its relative gravity channel and slump turbidite fan depositions were identified according to observation and description of cores combining with the numerous data of seismic and logging. Then, the depositional model was built depending on the analysis of palaeogeomorphology. The seismic attributes which are related to the hydrocarbon but relative independent were chosen to conduct the analysis, the reservoir area of the glutenite segment was found performing a distribution where the amplitude value is relatively higher, and finally the RMS amplitude attribute was chosen to conduct the attribute predicting. At the same time, the horizontal distribution of the sedimentary facies was analyzed qualitatively. At last, the sparse spike inversion method was used to conduct the acoustic impedance inversion, and the inversion result can distinguish glutenite reservoir which is greater than 5 m. This method quantitatively characterizes the distribution area of the favorable reservoir sand. 展开更多
关键词 Shengtuo area near-shore subaqueous fan gravity flow channel slump turbidite fan sedimentary mode acoustic impedance inversion
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Reductions in non-point source pollution through different management practices for an agricultural watershed in the Three Gorges Reservoir Area 被引量:13
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作者 Yaowu Tian Zhilin Huang Wenfa Xiao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期184-191,共8页
Non-point source water pollution generated by agricultural production is considered a major environmental issue in the Three Gorges Reservoir Area (TGRA) of China. The Annualised Agricultural Non-Point Source Pollut... Non-point source water pollution generated by agricultural production is considered a major environmental issue in the Three Gorges Reservoir Area (TGRA) of China. The Annualised Agricultural Non-Point Source Pollution (AnnAGNPS) model was selected to assess the impact of the application of various management treats, including seven crops, five fertilizer levels and three-group management practice scenarios, on water quality from Heigou River Watershed in TGRA. The scenario subsets include conservation tillage practice (CTP), conservation reserve program (CRP) and conversion of cropland into forestland program (CCFP). Results indicated that tea can not be replaced by other crops because comparatively tea resulted in a higher sediment yield. CTP with no-tillage was more effective to reduce sediment yield, but could increased nutrient loss. CRP reduced sediment yield significantly, but slightly benefited on nutrient loss. CCFP reduced not only sediment yield but also the nutrient loss significantly. The conversion of cropland with a slope greater than 10° into forestland was found to be the best scenario as the sediment yield export is less than 5 tons/ha and nutrient loss is within the permissible limit. 展开更多
关键词 non-point pollution management practice REDUCTION the Three Gorges Reservoir area
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Discussion on the Green Tax Stimulation Measure of Nitrogen Fertilizer Non-Point Source Pollution Control-Taking the Dongting Lake Area in China as a Case 被引量:8
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作者 XIANG Ping-an ZHOUYan +1 位作者 HUANG Huang ZHENG Hua 《Agricultural Sciences in China》 CAS CSCD 2007年第6期732-741,共10页
A study on designing the tax of nitrogen fertilizer can provide a new method for controlling nitrogen fertilizer non-point source pollution. The tax design of nitrogen fertilizer was discussed by utilizing the externa... A study on designing the tax of nitrogen fertilizer can provide a new method for controlling nitrogen fertilizer non-point source pollution. The tax design of nitrogen fertilizer was discussed by utilizing the external theory and the demand elasticity theory. The results indicated that the coefficient of price elasticity of nitrogen fertilizer demand is -0.21, which instructed that the market demand is in lack of elasticity in the short period and the impact of nitrogen fertilizer manufacturers is subtle. The 11 counties (cities and boroughs) in the Dongting Lake area in China, where the farmland nitrogen application surpassed the average ecological fertilization dosage, is listed to the taxation scope of nitrogen fertilizer tax. The environment loss will reduce 0.07 hundred million RMB yuan and the revenue will increase 0.89 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The loss, which was brought by the decreasing food supplies production, will be 0.58 hundred million RMB yuan and the net social benefit will be 0.38 hundred million RMB yuan following revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.49%. The variation scope of the income of farmers will range from -8.41 to 6.44%. The 5 areas, Yunxi Borough, Junshan Borough, Hanshou County, Jinshi City, and Ziyang Borough, had an increase in food supplies production after the revenue collection. The environment loss will reduce 0.01 hundred million RMB yuan and the revenue will increase 0.16 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The economic benefits, which was brought by the increasing cereals production, will be 0.67 hundred million RMB yuan and the net social benefit will be 0.84 hundred million RMB yuan after revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.06%. The variation scope of the increasing income of farmers will range from 0.69 to 6.44%. Considering the entire social welfare, taxation of nitrogen fertilizer will have more advantages than disadvantages in the Dongting Lake area. 展开更多
关键词 nitrogen fertilizer non-point source pollution TAX Dongting Lake area
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Combination Operation for Neutral Point of 35 kV Power Grids in Mountainous Area 被引量:2
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作者 YUAN Tao SIMA Wen-xia +1 位作者 RAN Rui ZHU Wei 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2626-2630,共5页
Based on a lot of measurement and analysis,this paper find that the unbalanced nature of 35 kV grids due to unsymmetrical capacitance values gives difficulty in neutral point operation in mountainous area.Improving co... Based on a lot of measurement and analysis,this paper find that the unbalanced nature of 35 kV grids due to unsymmetrical capacitance values gives difficulty in neutral point operation in mountainous area.Improving compensation of Petersen coil can rectify imbalance of voltage but bring up new problem that Petersen coil can not extinguish grounding arc effectively in fault.To put down contradiction mentioned above,this paper proposes a combination operation for neutral point of 35 kV grids as neutral point insulated in routine operation and grounding through Petersen coil in fault,then EMTP simulation is carried out.Simulation indicates that new neutral operation method can improve lightning withstand level and decrease trip-out rate of grids. 展开更多
关键词 山区 补偿电网 消弧线圈 投切运行 暂态分析
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SOME REMARKS ABOUT THE AREA-PRESERVING CONVEX CURVE FLOW IN THE PLANE
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作者 PiLing 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第4期417-428,共12页
Using Picard's theorem and the Leray-Schauder fixed point theorem to reinvestigate the area-preserving convex curve flow in the plane which is considered as a coupled system and thus different from the setting han... Using Picard's theorem and the Leray-Schauder fixed point theorem to reinvestigate the area-preserving convex curve flow in the plane which is considered as a coupled system and thus different from the setting handled by Gage. 展开更多
关键词 Picard's theorem Leray-Schauder fixed point theorem maximum principle area-preserving convex curve flow.
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Non point source ground water pollution trends in an urban area
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《Global Geology》 1998年第1期3-4,共2页
关键词 Non point source ground water pollution trends in an urban area
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深水浊积水道多点地质统计模拟——以安哥拉Plutonio油田为例 被引量:30
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作者 张文彪 段太忠 +3 位作者 刘志强 苑书金 林煜 许华明 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2016年第3期403-410,共8页
为对西非安哥拉Plutonio油田渐新统O73砂层组深水浊积水道分布进行模拟,基于浅层高频地震资料,对浅层水道沉积的形态特征及规模进行定量研究,通过相似性类比,用于指导油田深层单一水道砂体规模统计,然后建立定量化三维训练图像,最后利... 为对西非安哥拉Plutonio油田渐新统O73砂层组深水浊积水道分布进行模拟,基于浅层高频地震资料,对浅层水道沉积的形态特征及规模进行定量研究,通过相似性类比,用于指导油田深层单一水道砂体规模统计,然后建立定量化三维训练图像,最后利用多点地质统计学Snesim算法进行深水浊积水道分布模拟,并利用实钻井资料进行验证。研究表明:研究区浅层单一水道宽度、深度呈线性正相关关系,弯曲度与陆坡坡度呈指数负相关,单一水道砂体平均厚度13 m,平均宽度162 m。通过高精度梯度阻抗反演,提取浅层水道目标地质体作为深层水道定量化三维训练图像,采用Snesim算法进行随机模拟,深层浊积水道模拟结果忠实于井点数据,且水道砂体的平面形态、发育规模以及叠置关系具有受训练图像定量约束的特点,能够再现水道以及水道与天然堤间的空间结构与几何特征。 展开更多
关键词 深水沉积 浊积水道 多点地质统计模拟 浅水沉积 三维训练图像 渐新统 下刚果—刚果扇盆地
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RouterOS在多VLAN中的PPPOE解决方案 被引量:3
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作者 杨霖 肖志新 《吉首大学学报(自然科学版)》 CAS 2010年第6期43-45,共3页
以吉首大学校园网为案例,提出了基于RouterOS的多VLAN网络结构下的PPPOE解决方案,并就实施过程中遇到的问题提出了解决办法.
关键词 VLAN PPPOE 问题提出 网络结构 实施过程 解决方案 解决办法 校园网 大学 案例
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ITOPSIS与PSF耦合的采空区稳定性综合辨析 被引量:2
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作者 贾楠 吴超 +1 位作者 罗周全 谢承煜 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2016年第8期1182-1187,共6页
为提高地下金属矿采空区辨析的客观性,提出ITOPSIS及PSF耦合的综合辨析方法.首先引入TOPSIS方法并加以改进,形成适用于整体辨析的改进的TOPSIS(ITOPSIS)模型:1引入区间值直觉模糊集(IVIFS)以提高定性属性量化描述的客观性;2改进相对贴... 为提高地下金属矿采空区辨析的客观性,提出ITOPSIS及PSF耦合的综合辨析方法.首先引入TOPSIS方法并加以改进,形成适用于整体辨析的改进的TOPSIS(ITOPSIS)模型:1引入区间值直觉模糊集(IVIFS)以提高定性属性量化描述的客观性;2改进相对贴近度公式,避免了不可区分现象;3针对引发逆序问题的两个因素分别提出绝对理想解及IFAHP定权;4构建了采空区整体稳定性ITOPSIS等级量化区间,并将ITOPSIS运用于某金属矿山.然后,将基于点安全系数(PSF)的数值分析运用于2#,4#采空区局部稳定性分析,由PSF曲线具象地洞悉采空区局部稳定状态.研究结果为更好地综合分析采空区稳定性提供思路. 展开更多
关键词 采空区 稳定性 综合辨析 改进toPSIS 区间值直觉模糊集 点安全系数
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基于POI数据的城市功能识别与分布特征研究——以长春市区为例
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作者 孙明英 王灵芝 +2 位作者 钟巧莹 吴俊杰 梁安琪 《西南大学学报(自然科学版)》 CAS 北大核心 2025年第1期189-199,共11页
长春市是国家新型城镇化综合试点城市,识别长春市中心城区功能,针对当前存在的问题提出对策建议,对城市空间的优化与协调具有重要意义。以兴趣点(Point of Interest,POI)数据及开放街道地图(Open Street Map,OSM)数据为基础,结合核密度... 长春市是国家新型城镇化综合试点城市,识别长春市中心城区功能,针对当前存在的问题提出对策建议,对城市空间的优化与协调具有重要意义。以兴趣点(Point of Interest,POI)数据及开放街道地图(Open Street Map,OSM)数据为基础,结合核密度分析、实地调查验证等方法,识别长春市中心城区城市功能类型。结果表明:单一功能区中,商业功能区数量最多,居住功能区最少;主导—混合功能区中的商业主导功能区及交通主导功能区形成对商业聚集区与轨道交通系统的重要补充;细分—混合功能区特征显示功能混合程度从市中心向周边逐渐加大。经验证,城市功能识别结果符合长春市实际,由此提出对策建议:未来长春市中心城区应注重多中心发展格局,并加强绿地空间和公共服务设施建设。 展开更多
关键词 城市功能区 兴趣点数据 核密度估计 对比验证 长春市中心城区
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AutoCAD在土地测量中的应用 被引量:4
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作者 龚有亮 蒋理兴 曹歆宏 《地矿测绘》 2006年第1期34-35,共2页
介绍了AutoCAD在测定地界、量测土地面积、土地分割等方面的应用。实践证明,利用AutoCAD丰富的制图和量测功能,可大大减少野外测量和计算的工作量,简化土地测量工作,提高效率。
关键词 AUtoCAD 界址点 面积 土地分割 地籍测量
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基于AutoCAD建立图式符号库的方法 被引量:1
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作者 李娟 《北京测绘》 2005年第1期49-51,共3页
本文介绍了在AutoCAD中建立图式符号库的必要性,并针对图式符号的分类,分别介绍了对各类符号建立图式符号库的基本方法。
关键词 AUtoCAD 图式符号库 方法 点状符号 线状符号 面状符号
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AutoCAD环境下大比例尺地形图符号库的制作
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作者 李洪玉 李永香 +1 位作者 国仲凯 赵秀英 《测绘》 2009年第2期74-77,共4页
本文论述了在AutoCAD环境下,大比例尺地形图符号库(点状符号、线状符号、面状符号)的定制和开发方法,并用程序予以实现,在实际工作中具有一定的应用价值。
关键词 点状符号 线状符号 面状符号 定制
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