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Glacier area change and its impact on runoff in the Manas River Basin,Northwest China from 2000 to 2020
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作者 WANG Tongxia CHEN Fulong +5 位作者 LONG Aihua ZHANG Zhengyong HE Chaofei LYU Tingbo LIU Bo HUANG Yanhao 《Journal of Arid Land》 SCIE CSCD 2024年第7期877-894,共18页
Understanding the distribution and dynamics of glaciers is of great significance to the management and allocation of regional water resources and socio-economic development in arid regions of Northwest China.In this s... Understanding the distribution and dynamics of glaciers is of great significance to the management and allocation of regional water resources and socio-economic development in arid regions of Northwest China.In this study,based on 36 Landsat images,we extracted the glacier boundaries in the Manas River Basin,Northwest China from 2000 to 2020 using eCognition combined with band operation,GIS(geographic information system)spatial overlay techniques,and manual visual interpretation.We further analyzed the distribution and variation characteristics of glacier area,and simulated glacial runoff using a distributed degree-day model to explore the regulation of runoff recharge.The results showed that glacier area in the Manas River Basin as a whole showed a downward trend over the past 21 a,with a decrease of 10.86%and an average change rate of–0.54%/a.With the increase in glacier scale,the number of smaller glaciers decreased exponentially,and the number and area of larger glaciers were relatively stable.Glacier area showed a normal distribution trend of increasing first and then decreasing with elevation.About 97.92%of glaciers were distributed at 3700–4800 m,and 48.11%of glaciers were observed on the northern and northeastern slopes.The retreat rate of glaciers was the fastest(68.82%)at elevations below 3800 m.There was a clear rise in elevation at the end of glaciers.Glaciers at different slope directions showed a rapid melting trend from the western slope to the southern slope then to the northern slope.Glacial runoff in the basin showed a fluctuating upward trend in the past 21 a,with an increase rate of 0.03×10^(8) m^(3)/a.The average annual glacial runoff was 4.80×10^(8) m^(3),of which 33.31%was distributed in the ablation season(June–September).The average annual contribution rate of glacial meltwater to river runoff was 35.40%,and glacial runoff accounted for 45.37%of the total runoff during the ablation season.In addition,precipitation and glacial runoff had complementary regulation patterns for river runoff.The findings can provide a scientific basis for water resource management in the Manas River Basin and other similar arid inland river basins. 展开更多
关键词 glacier area glacial runoff climate change glacier boundary extraction distributed degree-day model Manas River Basin
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Radiometric Zircon Ages of a Tuff Sample from the Baishantou Member of Wuyun Formation,Jiayin:A Contribution to the Search for the K-T Boundary in Heilongjian River Area,China 被引量:8
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作者 SUZUKI Shigeyuki SUN Ge +2 位作者 Ulrich KNITTEL DANHARA Tohru IWANO Hideki 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第6期1351-1358,共8页
The existence of the Cretaceous-Tertiary (K/T) boundary in the non-marine succession is expected at Jiayin in the Heilongjiang River area, China. Zircons from a tuff sample from the Baishantou Member of Wuyun Format... The existence of the Cretaceous-Tertiary (K/T) boundary in the non-marine succession is expected at Jiayin in the Heilongjiang River area, China. Zircons from a tuff sample from the Baishantou Member of Wuyun Formation in Jiayin were analyzed by the laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U-Pb dating and fission-track dating methods. Ages of 64.1±0.7 Ma (U-Pb) and 61.7±1.8 Ma (fission-track dating) were obtained, which allow reevaluation of a previously reported late Maastrichian age for the tuff layer that was in conflict with the paleontological evidence. These results confirm the Danian age of the section in agreement with the paleontological evidence. 展开更多
关键词 U-Pb dating fission-track dating Baishantou section K/T boundary DANIAN Heilongjiang River area
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Permian/Triassic Boundary and Its Correlation in the Daxian-Xuanhan Area, Northeastern Sichuan Province, China 被引量:5
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作者 MA Yongsheng MOU Chuanlong +2 位作者 TAN Qinyin YU Qian WANG Ruihua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第1期56-62,共7页
There are different opinions about the Permian/Triassic boundary and its correlation in the Daxian-Xuanhan area because of lacking typical lithological symbols and fossil criterions. Especially, it is very hard to det... There are different opinions about the Permian/Triassic boundary and its correlation in the Daxian-Xuanhan area because of lacking typical lithological symbols and fossil criterions. Especially, it is very hard to determine the Permian/Triassic boundary in the Daxian-Xuanhan buried areas. This brings many difficulties to geological research and oil and gas exploration. Based on field investigation and studies of well cores, newly found fossils, lithological characteristics and well log analyses, the authors discussed the Permian/Triassic boundary in the Daxian-Xuanhan area and brought forward a specific scheme for its determination and regional correlation. 展开更多
关键词 Permian/Triassic boundary CORRELATION Daxian-Xuanhan area
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Annual variation in Calanus sinicus abundance and population structure in the northern boundary area of the Yellow Sea Cold Water Mass 被引量:2
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作者 尹洁慧 张光涛 +2 位作者 赵增霞 王世伟 万艾勇 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第6期1284-1294,共11页
The Yellow Sea Cold Water Mass (YSCWM) was suggested as an over-summering site of the dominant copepod species Calanus sinicus in coastal Chinese seas. Population abundance and structure were investigated by monthly... The Yellow Sea Cold Water Mass (YSCWM) was suggested as an over-summering site of the dominant copepod species Calanus sinicus in coastal Chinese seas. Population abundance and structure were investigated by monthly sampling along three transects across the northern boundary of the YSCWM during 2009-2010. Results show that thermal stratification existed from June to October and that the vertical thermal difference increased with depth. Generally, total abundance was lowest in October and highest in June, and the female/male sex ratio was highest in February and lowest in August. Evident spatial differences in abundance were observed during the existence of the YSCWM. In June, total abundance averaged 158.8 ind/m~ at well-stratified stations, and 532.1 ind/m3 at other stations. Similarly, high abundances of 322.0 and 324.4 ind/m3 were recorded from July to August inside the YSCWM, while the abundance decreased from 50.4 to 1.9 ind/m3 outside the water mass. C. sinicus distribution tended to even out over the study area in September when the YSCWM disappeared. We believe that the YSCWM may retard population recruitment in spring and preserve abundant cohorts in summer. The summer population was transported to neritic waters in autumn. In addition to low temperatures, stable vertical structure was also an essential condition for preservation of the summer population. C. sinicus can survive the summer in marginal areas in high abundance, but the population structure is completely different in terms of C5 proportion and sex ratio. 展开更多
关键词 Calanus sinicus Yellow Sea Cold Water Mass (YSCWM) over-summer strategy boundary area thermal stratification
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Carbon Isotope Excursions and Paleo-Oceanography of the Ordovician–Silurian Boundary Carbonate Rocks from the Xainza Area, Tibet 被引量:2
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作者 YUAN Tao YI Haisheng +2 位作者 ZHANG Shuai CAI Zhanhu LI Gaojie 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2052-2054,共3页
Objective The Ordovician–Silurian transitional period is a special time when the global paleo-environment changed greatly.It witnessed the first mass extinction as of Phanerozoic period and glaciations that occurred ... Objective The Ordovician–Silurian transitional period is a special time when the global paleo-environment changed greatly.It witnessed the first mass extinction as of Phanerozoic period and glaciations that occurred frequently at a large scale in a very short time,which has thus attracted much attention among geoscientists at home and abroad. 展开更多
关键词 Carbon Isotope Excursions and Paleo-Oceanography of the Ordovician Silurian boundary Carbonate Rocks from the Xainza area TIBET GM
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Use of the area of main influence to fix a relevant boundary for mining damages in Germany
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作者 Denise Müller Axel Preusse 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第1期79-83,共5页
In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-A... In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in 2016.Especially the production of gas had to be regulated.With the legislation amendment, the Subsidence-Area Mining Regulation has been revised, too.The changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground storage.Although the Subsidence-Area Mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining damages.The determination and prediction of this boundary above caverns are presented in this paper.In addition, further elements of ground movements and their relevance to mine damages are analyzed.The usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on buildings.Furthermore, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages. 展开更多
关键词 Ground movements area of MAIN INFLUENCE boundary for MINING DAMAGES Subsidence-area MINING regulation SUBSIDENCE detection Modeling above caverns
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An advanced segmentation using area and boundary tracing technique in extraction of lungs region
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作者 Kiran THAPALIYA Sang-Woong LEE +2 位作者 Jae-Young PYU Heon JEONG Goo-Rak KWON 《Journal of Central South University》 SCIE EI CAS 2014年第10期3811-3820,共10页
A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment... A new method is presented for the segmentation of pulmonary parenchyma. The proposed method is based on the area calculation of different objects in the image. The main purpose of the proposed algorithm is the segment of the lungs images from the computer tomography(CT) images. The original image is binarized using the bit-plane slicing technique and among the different images the best binarized image is chosen. After binarization, the labeling is done and the area of each label is calculated from which the next level of binarized image is obtained. Then, the boundary tracing algorithm is applied to get another level of binarized image. The proposed method is able to extract lung region from the original images. The experimental results show the significance of the proposed method. 展开更多
关键词 bit-plane slicing technique connected component labeling area tracing boundary tracing
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The Calculation of Stress-Strain State of Anisotropic Composite Finite-Element Area with Different Boundary Conditions on the Surface
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作者 Bergulyov Anton 《World Journal of Mechanics》 2014年第1期31-36,共6页
The numerical analytic research approach of stress-strain state of anisotropic composite finite element area with different boundary conditions on the surface, is represented below. The problem is solved by using a sp... The numerical analytic research approach of stress-strain state of anisotropic composite finite element area with different boundary conditions on the surface, is represented below. The problem is solved by using a spatial model of the elasticity theory. Differential equation system in partial derivatives reduces to one-dimensional problem using spline collocation method in two coordinate directions. Boundary problem for the system of ordinary higher-order differential equation is solved by using the stable numerical technique of discrete orthogonalization. 展开更多
关键词 COMPOSITE FINITE-ELEMENT areas boundary Conditions ELASTICITY Theory SPLINE Approximation COLLOCATION Methods
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Atmospheric Carbon Dioxide Reconstruction and Ocean Acidification Deduced from Carbon Isotope Variations across the Triassic–Jurassic Boundary in the Qiangtang Area, Tibetan Plateau
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作者 YI Fan YI Haisheng +1 位作者 XIA Guoqing CAI Zhanhu 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2055-2057,共3页
Objective The end-Triassic mass extinction was one of the five most profound Phanerozoic extinction events.This event was accompanied by a series of significant environmental changes,of which the most notable is the e... Objective The end-Triassic mass extinction was one of the five most profound Phanerozoic extinction events.This event was accompanied by a series of significant environmental changes,of which the most notable is the emergence of warm climate and the world-wide disappearance of carbonate platform. 展开更多
关键词 PCO Ca Jurassic boundary in the Qiangtang area Tibetan Plateau Atmospheric Carbon Dioxide Reconstruction and Ocean Acidification Deduced from Carbon Isotope Variations across the Triassic
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灰飞虱自动识别计数方法研究
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作者 程麒文 邱白晶 《中国农机化学报》 北大核心 2024年第7期166-171,共6页
为更精确地施药,提供可靠的虫量数据,提出一种基于图像识别技术的灰飞虱数量计算方法。设定由拍摄距离和相机调节倍数组成三组拍摄条件,融合区域面积、区域圆度和边界直径三个参数组合构成识别计数模型,利用边缘检测和区域填充完成图像... 为更精确地施药,提供可靠的虫量数据,提出一种基于图像识别技术的灰飞虱数量计算方法。设定由拍摄距离和相机调节倍数组成三组拍摄条件,融合区域面积、区域圆度和边界直径三个参数组合构成识别计数模型,利用边缘检测和区域填充完成图像中的个体提取,每组条件下分别计算5张单个长翅和短翅的参数值作为标准。拍摄条件相同的情况下,分别计算4张相互独立和4张有轻微连接的灰飞虱的计数图像,将每个区域的结果比对参数标准值范围,如果三个参数均在范围内,则输出1;至少有一个参数不符合,重新计算该区域面积和边界直径,当同时符合标准值的2倍时,输出2。试验结果表明:灰飞虱全为独立的图像中,有8张相对错误率为0%,3张小于10%,1张为13.3%;轻微连接的图像中,有2张相对错误率为0%,6张小于10%,4张为10%~25%,能满足灰飞虱数量的自动计算。 展开更多
关键词 灰飞虱 自动识别计数 区域面积 区域圆度 边界直径
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世界地质公园规划编制中若干问题探讨——以光雾山-诺水河世界地质公园为例
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作者 刘明 《四川地质学报》 2024年第2期371-376,共6页
地质公园规划是每个地质公园管理和后期建设的重要依据,也是地质公园能够可持续发展的重要保障。以光雾山-诺水河世界地质公园规划编制实例,从技术层面来探讨在世界地质公园规划编制中地质公园范围划定、地质遗迹保护区划定及保护级别... 地质公园规划是每个地质公园管理和后期建设的重要依据,也是地质公园能够可持续发展的重要保障。以光雾山-诺水河世界地质公园规划编制实例,从技术层面来探讨在世界地质公园规划编制中地质公园范围划定、地质遗迹保护区划定及保护级别确定、总体空间布局策划、功能区区划等问题,为世界地质公园规划编制及探索世界地质公园规划编制技术要求提供参考。 展开更多
关键词 光雾山-诺水河 地质公园范围 地质遗迹保护区 地质公园规划:功能区
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基于生态系统完整性的自然保护地边界划定方法--以欧美地区的实践为例
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作者 李咏华 姚松 高欣芸 《华中建筑》 2024年第4期142-146,共5页
科学划定自然保护地的边界关系到保护目标的实现和管理措施的制定,是自然保护地规划和建设的首要环节。该文以欧美地区的实践案例为例,介绍了基于生态系统完整性的自然保护地边界划定方法。首先对现有自然保护地边界划定方法进行梳理,... 科学划定自然保护地的边界关系到保护目标的实现和管理措施的制定,是自然保护地规划和建设的首要环节。该文以欧美地区的实践案例为例,介绍了基于生态系统完整性的自然保护地边界划定方法。首先对现有自然保护地边界划定方法进行梳理,在此基础上介绍了面向实施的景观单元(Operational Landscape Units)的概念和划定流程;其次梳理了韦斯特布鲁克圩田保护边界划定和旧金山湾海岸带保护边界划定的案例;最后为我国自然保护地的边界划定提出建议。 展开更多
关键词 面向实施的景观单元 自然保护地 生态系统完整性 边界划定 生态过程
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协调发展视角下大南昌都市圈城市增长边界的划定
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作者 刘珂 蔡海生 张学玲 《地理与地理信息科学》 CSCD 北大核心 2024年第2期37-43,共7页
科学划定城市增长边界(UGB)能合理引导城市发展方向,有效抑制无序蔓延。基于协调发展视角,结合多目标土地利用适宜性评价方法与PLUS模型划定大南昌都市圈刚性UGB及自然增长、政策约束、协调发展3种情景下的弹性UGB。结果表明:①多目标... 科学划定城市增长边界(UGB)能合理引导城市发展方向,有效抑制无序蔓延。基于协调发展视角,结合多目标土地利用适宜性评价方法与PLUS模型划定大南昌都市圈刚性UGB及自然增长、政策约束、协调发展3种情景下的弹性UGB。结果表明:①多目标土地利用适宜性呈现空间差异且存在重叠和交叉,协调发展最适宜区与农业生产最适宜区、生态保护最重要区重叠面积相比城镇建设最适宜区均有所下降;②刚性UGB面积占研究区总面积的76.11%,保障大南昌都市圈城市扩张严格遵循生态保护红线和粮食安全底线;③PLUS模型模拟结果总体呈耕地、林地、草地、未利用地减少以及水域和建设用地增加的趋势,其中建设用地扩张最显著,但协调发展情景下城市扩张得到有效约束,且该情景下弹性UGB能有效减缓城市扩张占用农业或生态价值最高区域,更能优化城市景观格局。研究结果有利于引导和实现大南昌都市圈城市可持续发展,也可为其他城市三生空间协调发展提供参考。 展开更多
关键词 协调发展目标 PLUS模型 城市增长边界 大南昌都市圈
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Study on the Spatial Pattern Changes of Land Use Based on Fractal Dimensions in Tianjin New Coastal Area 被引量:3
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作者 白新萍 《Agricultural Science & Technology》 CAS 2011年第6期879-882,919,共5页
[Objective] The aim was to discuss the spatial pattern changes of land use in Tianjin new coastal area based on fractal dimensions.[Method] By dint of remote and geographic information system technology to obtain the ... [Objective] The aim was to discuss the spatial pattern changes of land use in Tianjin new coastal area based on fractal dimensions.[Method] By dint of remote and geographic information system technology to obtain the data of urban land use in new coastal area from 1993 to 2008,the boundary dimension,radius dimension and information dimension of each land use type were calculated based on fractal dimension.In addition,the revealed land use spatial dimension changes characteristics were analyzed.[Result] The spatial distribution of each land use type in new costal area had distinct fractal characteristics.And,the amount and changes of three types of dimension values effectively revealed the changes of complicatedness,centeredness and evenness of spatial pattern of land use in the study area.The boundary dimension of unused land and salty earth increased incessantly,which suggested its increasing complicatedness.The boundary of the port and wharf and shoal land was getting simpler.The radius dimension of the cultivated land was larger than 2,which suggested that its area spread from center to the surroundings;the one in salty land and waters distributed evenly within different radius space to the center of the city;the one in other land use types reduced gradually from center to the surroundings.The information dimension value in the woodland and orchard land,unused land and shoal land was small,and was in obvious concentrated distribution;the spatial distribution of cultivated and salty land concentrated in the outside area;the construction area in the port and wharf spread gradually on the basis of original state;the spatial distribution of waters and residents and mines were even.[Conclusion] Applying fractal dimensions to the study of spatial pattern changes of urban land use can make up for some disadvantages in classical urban spatial pattern quantitative research,which has favorable practical value. 展开更多
关键词 Land use Fractal dimension boundary dimension Radial dimension Information dimension Tianjin New Coastal area
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国家气候观象台多维度观测能力建设及科学研究——以深圳为例
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作者 李磊 邱宗旭 +7 位作者 罗红艳 杨红龙 高瑞泉 卢超 张丽 江崟 庄红波 唐佳慧 《大气科学》 CSCD 北大核心 2024年第5期1937-1951,共15页
国家气候观象台是中国国家级气象观测的重要节点,发展国家气候观象台的观测能力,并依托其开展有特色的科学研究,有助于推动我国大气科学发展。深圳国家气候观象台是我国珠三角经济圈环境综合观测区唯一的国家级气候观象台,经过20余年的... 国家气候观象台是中国国家级气象观测的重要节点,发展国家气候观象台的观测能力,并依托其开展有特色的科学研究,有助于推动我国大气科学发展。深圳国家气候观象台是我国珠三角经济圈环境综合观测区唯一的国家级气候观象台,经过20余年的持续不断建设,已具备了城市—郊区的对比监测、气象—环境的联合监测、地面—高空的立体监测和陆地—海洋的协同监测等多方面的监测能力。基于深圳国家气候观象台的观测数据,大气科学领域的学者们已在粤港澳大湾区城市气候、边界层风特性及致灾机理、大气环境与环境气象、气候资源、地闪雷电特征等多个领域开展研究并取得了丰硕的成果,进一步丰富了对这些领域的科学认识。此外,深圳国家气候观象台还支撑了深圳本地的防灾减灾、城市管理、城市规划以及生态文明建设等工作,已逐渐成为发挥气象观测社会效益的典范。 展开更多
关键词 深圳国家气候观象台 粤港澳大湾区 城市气候 环境气象 大气边界层物理
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不同透水条件下海底饱和沉积层动力响应特性分析
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作者 李腾达 单振东 +1 位作者 李金恺 景立平 《地震工程与工程振动》 CSCD 北大核心 2024年第2期169-182,共14页
海床沉积层的透水条件可以直接影响其在地震中的动力响应特性,但是在现有的理论研究中,大部分都直接假设海床沉积层的底部为不透水边界。为此,基于Biot饱和多孔介质理论,通过求解沉积层瞬态响应和稳态响应的解析解或半解析解,研究了沉... 海床沉积层的透水条件可以直接影响其在地震中的动力响应特性,但是在现有的理论研究中,大部分都直接假设海床沉积层的底部为不透水边界。为此,基于Biot饱和多孔介质理论,通过求解沉积层瞬态响应和稳态响应的解析解或半解析解,研究了沉积层底部透水条件对其在地震中动力响应特性的影响。研究结果表明,在底部位移激励的条件下,快波和慢波经过沉积层的不透水底部边界时会产生一类压缩波,经过沉积层完全透水底部边界时会产生两类压缩波;即使在相同的激励条件下,不同透水性能的沉积层中产生的两类压缩波的振动幅值也具有非常显著的差异;沉积层底部透水条件也会影响海床的频率响应特性,低频时底部透水的沉积层的位移放大系数较大;相反,高频时底部不透水的沉积层的位移放大系数较大。 展开更多
关键词 海域地震 动力响应 透水边界条件 饱和沉积层 动力渗透系数
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一种基于多维度生态评估的自然保护地边界优化方法——以三江源国家公园黄河源园区为例
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作者 李业涵 刘楠 吴雪飞 《中国园林》 CSCD 北大核心 2024年第1期119-125,共7页
科学准确划定自然保护地边界是设立保护地及制定和实施保护管理措施的首要前提,厘清自然保护地边界是在整合优化自然保护地的过程中首要解决的问题。以生物多样性与生态系统服务双保护为目标,基于In VEST和SWAT模型综合评估生态系统服务... 科学准确划定自然保护地边界是设立保护地及制定和实施保护管理措施的首要前提,厘清自然保护地边界是在整合优化自然保护地的过程中首要解决的问题。以生物多样性与生态系统服务双保护为目标,基于In VEST和SWAT模型综合评估生态系统服务,并基于生物完整性等级(Degree of Biological Integrity,DBI)和生态增强因子(Enhancement Factor,EF)评估了保护成本及生态效益,提出了一种自然保护地的边界优化方法。基于这种方法将三江源国家公园黄河源园区的现有边界优化为涵盖总体自然边界、核心生态边界与管理边界的多重边界,从而使生态系统服务得到最大限度的保护,使生物多样性保护得到一定程度的加强,并同时考虑管理效益,确保新增保护成本较低。 展开更多
关键词 风景园林 自然保护地 边界 生态系统服务 生态评估 保护成本 生态效益
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基于形态聚类的老旧小区临街边界优化研究——以安徽省合肥市老城区为例
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作者 徐浩 曹海婴 《住宅产业》 2024年第6期40-42,共3页
老旧小区临街边界作为日常生活的重要场所是公共与私密的过渡区域,但随着小区的逐渐陈旧,当前浮现出较多亟待解决的问题。本文以安徽省合肥市老城区为例,量化研究老旧小区临街边界的空间形态,运用聚类分析的方法根据形态特征总结出小尺... 老旧小区临街边界作为日常生活的重要场所是公共与私密的过渡区域,但随着小区的逐渐陈旧,当前浮现出较多亟待解决的问题。本文以安徽省合肥市老城区为例,量化研究老旧小区临街边界的空间形态,运用聚类分析的方法根据形态特征总结出小尺度渗透型、中小尺度凹凸型、中大尺度封闭型及大尺度平整型四类边界,并根据个性问题分别提出针对性的优化策略,以期为老旧小区临街边界形态划分提供全新依据,同时为样本边界更新提供一定的参考价值。 展开更多
关键词 老旧小区 临街边界 聚类分析 空间形态
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生态系统保护和修复的初步探讨 被引量:3
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作者 张兴云 李维 胡译元 《林业勘查设计》 2024年第2期46-49,共4页
通过对抚远市界江界河区域生态系统存在主要问题及其生态系统保护和修复价值分析,提出该区域生态系统保护和修复技术要求,研究制定保护和修复方案,为持续推进抚远市界江界河区域东北森林带中的林地、湿地与草原生态系统的保护修复等项... 通过对抚远市界江界河区域生态系统存在主要问题及其生态系统保护和修复价值分析,提出该区域生态系统保护和修复技术要求,研究制定保护和修复方案,为持续推进抚远市界江界河区域东北森林带中的林地、湿地与草原生态系统的保护修复等项工作提供参考。 展开更多
关键词 生态系统 保护和修复 界江界河区域 抚远市
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破围与限界:对中央苏区时期妇女角色的再考察
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作者 要仲宇 张博文 《黑河学院学报》 2024年第1期169-172,共4页
中央苏区时期,中国共产党把妇女运动与政治革命运动紧密结合,通过开展一系列社会革命让妇女取得了政治、经济、文化教育、婚姻自主等方面全面的解放,从而启发妇女的政治意识,使妇女成为支持苏维埃运动的中流砥柱群体。然而,妇女在整个... 中央苏区时期,中国共产党把妇女运动与政治革命运动紧密结合,通过开展一系列社会革命让妇女取得了政治、经济、文化教育、婚姻自主等方面全面的解放,从而启发妇女的政治意识,使妇女成为支持苏维埃运动的中流砥柱群体。然而,妇女在整个革命中扮演的不仅只有革命支持者与被解放者这两重身份,受限于革命政权的生存压力,妇女自身的女性角色常常处于失语状态。革命中的妇女角色的“破围”与“限界”需要全新的考察。 展开更多
关键词 中央苏区时期 妇女角色 妇女解放 限界与突破
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