居民幸福感的城际差异及其影响因素探析——基于多尺度模型的研究   总被引：5，自引：2，他引：3  

党云晓  张文忠  谌丽  湛东升 《地理研究》2018,37(3):539-550

居民幸福感是建设和谐社会与检验城镇化质量的重要内容。地理学视角的研究围绕幸福感空间差异展开,解读背景环境特征与其关系。国内已有研究缺乏基于个体与城市尺度的联合分析,且缺少城市特征对幸福感影响机制的综合考虑。以环渤海地区44个城市为例,基于大规模调研问卷,采用多尺度建模方法,分析居民幸福感的城际差异及影响因素。结果表明,居民幸福感在城市之间存在显著差异;经济最发达的城市居民幸福感最低;城市规模对居民幸福感有负面影响,收入可以缓解城市规模负面影响的程度;环境污染对居民幸福感有显著的负面影响,积极的环境评价对居民幸福感有正面影响;良好的社会治安与人文环境对居民幸福感影响为正。  相似文献   

长江三角洲人口与经济的非均衡格局及其影响因素研究   总被引：3，自引：2，他引：1  

闫东升  杨槿  高金龙 《地理科学》2018,38(3):376-384

人口与经济分布格局是反映区域差异的重要指标。结合不一致指数、重心方法及不均衡指数等对长江三角洲人口与经济的非均衡格局演变进行研究,并基于2000~2015年的面板数据回归对其影响因素进行实证研究。研究发现,长江三角洲人口与经济非均衡格局呈现相对稳定状况,但随着区域发展格局转变带来的人口与经济分布格局的差异化演变,区域人口与经济的整体非均衡性有所弱化。对人口与经济非均衡格局影响因素分析表明,不同时期人口与经济不一致指数影响因素存在差异,在始终受城市发展差异影响的同时也伴随着市场力量的趋强和政府影响的弱化。  相似文献   

北京地区地源热泵系统地质条件评估工作浅谈   总被引：1，自引：1，他引：0  

姜再新  石小林  刘学清  刘冬生  马学利  张梅  司炳艳 《城市地质》2008,3(3):1-4

本文介绍了北京地区地源热泵系统地质条件评估工作的相关背景,详细阐述了地质条件评估的本质是把客观真实的地质、热工技术认识与项目可研工作的要求结合起来,深刻分析了地质条件对地源热泵系统项目应用的适合性,风险性和可行性的影响,提出地源热泵系统技术具有典型的双刃剑特征,仍有许多技术问题值得深入思考和研究。  相似文献   

白云南洼恩平组海相烃源岩空间展布规律及发育模式     

张义娜  张功成  杨海长  杨东升 《海洋地质前沿》2014,30(12):17-24

通过借助层序地层学理论、构造古地貌分析、古生物资料、沉积速率与可容纳空间关系对比,以及典型地震相识别、地震相与沉积相剖面及平面分析等,结合区域地质资料及前人的研究成果,对白云南洼恩平组烃源岩的叠置关系、影响因素、空间展布规律及发育模式进行了研究,得到如下认识:白云南洼恩平组对应一个完整的二级层序,可细分为3个三级层序,自下至上为SQ1、SQ2、SQ3,海平面总体为上升特征,SQ3的最大海泛面对应了整个恩平组二级层序的最大海泛面;白云南洼恩平组为局限浅海环境,具备发育较好海相烃源岩的条件,稳定半封闭的古构造背景,有利于烃源岩有机质的富集保存;沉积速率小,且小于可容空间增长速率,沉积物向陆退积,沉积水体深度变大,利于海相烃源岩的发育;恩平组烃源岩为大陆边缘半闭塞—欠补偿—湿润海湾模式,优质烃源岩主要发育在受隆起及断层遮挡形成的海湾区。  相似文献   

Spatiotemporal characteristics,patterns, and caus-es of land-use changes in China since the late 1980s   总被引：10，自引：0，他引：10  

LIU Jiyuan  KUANG Wenhui  ZHANG Zengxiang  XU Xinliang  QIN Yuanwei  NING Jia  ZHOU Wancun  ZHANG Shuwen  LI Rendong  YAN Changzhen  WU Shixin  SHI Xuezheng  JIANG Nan  YU Dongsheng  PAN Xianzhang  CHI Wenfeng 《地理学报》2014,24(2):195-210

Land-use/land-cover changes (LUCCs) have links to both human and nature interactions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year intervals from the late 1980s to 2010,with standard procedures based on Landsat TM\ETM+ images. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics,differences,and causes of land-use changes at a national scale were then examined. The main findings are summarized as follows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change decreased in the south and increased in the north,but the total area remained almost unchanged. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly,were mainly distributed in the east,and gradually spread out to central and western China. Woodland decreased first,and then increased,but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region,the southeastern coastal areas,the midstream area of the Yangtze River,and the Sichuan Basin;(2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China;(3) continuous transformation from rain-fed farmlands in northeast China to paddy fields;and (4) effectiveness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia,the Loess Plateau,and southwestern mountainous areas. In the last two decades,although climate change in the north affected the change in cropland,policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century,the anthropogenic factors that drove variations in land-use patterns have shifted the emphasis from one-way land development to both development and conservation.The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries,the internal characteristics of zones,and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning,variations in unit boundaries,and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored.  相似文献   

Characterization of organic aerosols in Beijing using an aerodyne high-resolution aerosol mass spectrometer     

ZHANG Junke  WANG Yuesi  HUANG Xiaojuan  LIU Zirui  JI Dongsheng  SUN Yang 《大气科学进展》2015,32(6):877-888

Fine particle of organic aerosol(OA), mostly arising from pollution, are abundant in Beijing. To achieve a better understanding of the difference in OA in summer and autumn, a high-resolution time-of-flight aerosol mass spectrometer(HRTo F-AMS, Aerodyne Research Inc., USA) was deployed in urban Beijing in August and October 2012. The mean OA mass concentration in autumn was 30 ± 30 μg m-3, which was higher than in summer(13 ± 6.9 μg m-3). The elemental analysis found that OA was more aged in summer(oxygen-to-carbon(O/C) ratios were 0.41 and 0.32 for summer and autumn,respectively). Positive matrix factorization(PMF) analysis identified three and five components in summer and autumn, respectively. In summer, an oxygenated OA(OOA), a cooking-emission-related OA(COA), and a hydrocarbon-like OA(HOA)were indentified. Meanwhile, the OOA was separated into LV-OOA(low-volatility OOA) and SV-OOA(semi-volatile OOA);and in autumn, a nitrogen-containing OA(NOA) was also found. The SOA(secondary OA) was always the most important OA component, accounting for 55% of the OA in the two seasons. Back trajectory clustering analysis found that the origin of the air masses was more complex in summer. Southerly air masses in both seasons were associated with the highest OA loading, while northerly air masses were associated with the lowest OA loading. A preliminary study of OA components,especially the POA(primary OA), in different periods found that the HOA and COA all decreased during the National Day holiday period, and HOA decreased at weekends compared with weekdays.  相似文献   

D-InSAR与最优化算法的采空区几何参数反演     

卜璞  李朝奎  杨文涛  廖孟光 《测绘科学》2021,46(5):143-152

针对采矿后遗留的采空区会诱发严重的地质灾害问题,该文提出一种采空区几何参数的反演算法,旨在及时探明采空区的分布特征与几何形状,进而有效控制灾害的发生.该文通过合成孔径雷达差分干涉(D-InSAR)技术获取采空区上方的地表连续沉降场,通过概率积分模型建立采空区几何特征与地表沉降场之间的相互关系,引入BFGS最优化算法对采空区的几何参数进行反演.仿真实验结果表明:在加入5 mm随机误差的情况下,BFGS算法能够有效反演出全部参数,且反演精度略高于遗传算法(SA)和模拟退火(GA)算法;同时,在不同的初值条件下,BFGS算法反演结果的数值稳定性与反演精度仍明显优于其他两种算法.工程应用中,反演结果显示SA与GA算法的相对误差平均值都超过了 10％,而BFGS算法的相对误差平均值只有4.73％,进一步验证了 BFGS算法的可靠性.  相似文献   

基于GIS的土壤重金属污染模拟扩散研究及应用     

王建  夏天  罗政  杨金辉  卜明伟  李功权 《测绘与空间地理信息》2022,45(1):74-78

土壤污染是全球三大环境污染之一,目前、重金属污染是造成我国土壤污染主要原因之一,土壤中的重金属元素会严重危害相关农作物的生长,且传统的土壤重金属污染研究和污染模型的建立大部分是通过单一的数据表格来对结果进行分析说明,不够直观和简明。因此,基于地理信息系统十分强大的空间数据管理及空间分析能力,结合相关算法,构建出土壤中重金属污染扩散迁移模型,并将WebGIS技术和土壤重金属污染扩散迁移起来,对土壤重金属污染数据用GIS技术进行分析和展示。研究表明:改进之后的模型及程序与传统模型及程序相比,数据的展示更加直观,对数据展示更加多维,可以辅助政府环保相关部门对土壤中的重金属污染制订更加精准的治理方案。  相似文献   

Experimental Anelastic Strain Recovery Compliance of Three Typical Rocks     

Lu Gao  Weiren Lin  Dongsheng Sun  Hongcai Wang 《Rock Mechanics and Rock Engineering》2014,47(6):1987-1995

The experimental determination of anelastic strain recovery (ASR) compliances for three types of rocks (granite, marble, and sandstone) was performed in the laboratory. Preloading of specimens for uniaxial compression creep tests was at 50 % of the uniaxial compressive strength (UCS) for each rock type. We obtained the shear mode Jas(t) and volumetric mode Jav(t) ASR compliances and calculated the ratio of Jas(t) to Jav(t). The Kelvin model for rock rheology was then applied in numerical simulations and the results were in good agreement with the measured data for Jas(t) and Jav(t). These results showed that both the magnitude and rate of increase of the ASR compliances are strongly dependent on the rock type, and the values of the Jas(t)/Jav(t) ratio for a loading of 50 % of the UCS showed a trend leading to different constants for each of the three rock types. Further experimental and numerical analyses showed approximate power-law relationships between the ASR compliances at 50 % of UCS, and both the UCS and the tangential Young’s modulus at 50 % of UCS (E _t50). These relationships may be useful for the preliminary estimation of ASR compliances.  相似文献   

基于UofC模型的多系统组合PPP解算性能分析     

布金伟  陈云波  左小清  常军  李小龙 《测绘通报》2017,(11):11-16

针对GNSS多系统组合进行PPP定位的问题,推导了基于UofC模型的多系统组合PPP的函数模型和随机模型。最后采用IGS观测站30 d的部分观测数据对不同组合模式的PPP进行了解算。试验分析结果表明：GNSS多系统组合PPP收敛时间与GPS单系统相比可以缩短30%~50%。对于定位精度,在观测时长较短时（如0.5 h）,GNSS多系统组合PPP整体上具有较优的定位精度,N、E方向偏差和标准差分别为0.3、0.5 cm和1.9、4.3 cm,短时间内由于对流层参数与垂直方向的强相关性,使得U方向精度稍差。此外,在卫星高度截止角大于40°的条件下,单系统可见卫星数不足从而导致无法进行连续定位,但多系统组合具有更多的可视卫星,仍能获得较好的定位精度,使其在建筑物密集区、山区和卫星遮挡较为严重的恶劣条件下具有实际应用价值。  相似文献