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1.
Using Designer's Simulation Toolkit DeST h developed by Tsinghua University, research was carried out on the energy consumption of a typical residential building in Ningbo, P. R. China, with a focus on the heat transfer coefficient of external windows facing every direction. Results show that variation of the heat transfer coefficient of external windows in all directions has a substantial effect on energy consumption for heating but little effect on energy consumption for cooling. It is difficult to decrease cooling energy consumption by decreasing the heat transfer coefficient of external windows in summer. The heat transfer coefficient of external windows facing south has a significant effect on building energy consumption, but the windows facing north have less effect, and those facing east and west have the least impact. Decreasing the heat transfer coefficient of external windows facing north and south from 4.7 to 3.2 produces the most favorable performance cost ratio for energy saving investments. Reasons for the decrease in the heat transfer coefficient of external windows leading to increased air conditioning energy consumption were discussed. The conclusions are useful for guiding energy efficient building design in other subtropical cities.  相似文献   

2.
乡村小康和谐社会的量化研究   总被引:1,自引:0,他引:1  
以县(市)为研究单元,应用两阶段聚类法,对广西乡村小康和谐社会的发展状况进行综合分析研究,揭示各研究单元与指标变量的关系及其空间分布规律。结果表明,广西76个县(市)可分为4种发展类型:高度协调发展类型Ⅰ,中等协调发展类型Ⅱ,初级协调发展类型Ⅲ和整体发展滞后类型Ⅳ。各类型的发展水平差异有明显地域联系和分异特征,总格局为东高西低,东南高西北低,空间结构呈点轴开发模式。  相似文献   

3.
Hainan Island     
《分子植物育种》2007,5(2):191-191
Geographical location Hainan Province is the solely tropical island province of China, administrating Hainan main island,the islets and reefs of Xisha, Nansha, Zhongsha and their surrounding waters. Hainan Province lies in the central part of  相似文献   

4.
Kain's spatial mismatch hypothesis (SMH) (1968) highlights the segregation of Black population in the inner city as well as the decentralization of jobs, both of which played a role in the poor labor market outcomes for Black residents in the inner city. Demographic and economic changes in U.S. metropolitan areas since the late 20th century have transformed the urban spatial structure. This paper aims to revisit the SMH and investigate whether the spatial pattern of mismatch has changed as a result of geographic shifts in the Black population. This paper specifically examines how the suburbanization of the Black population has affected the geographic patterns of mismatch and whether the mismatch is disappearing in the major U.S. metropolitan areas. Using spatial measures of mismatch, this paper presents intra-metropolitan spatial mismatch patterns that capture the clustering of jobs and the Black population based on their relative distributions, showing that the overall level of spatial mismatch declined in major U.S. metropolitan areas between 2000 and 2015. However, geographical evidence reveals that the spatial mismatch has shifted to the outer suburbs, replicating city-suburb spatial inequality, implying that although mismatch may have declined in the inner city due to Black suburbanization, spatial mismatch continue to persist in U.S. metropolitan areas in Black suburbs. The findings also demonstrate that although spatial mismatch generally declined in the inner city, it increased in cities with high inner city polarization, particularly New York, Chicago, San Francisco, and Seattle.  相似文献   

5.
为了深入了解南海上层海洋热力状态的变化规律,利用1980—2015年共36年GODAS月平均海温资料,将5~366 m的垂直平均海温表征南海地区海洋上层的热含量,分析了南海海洋上层热状态的水平和垂直分布特征以及季节和年际变化特征。结果表明:年平均南海热含量水平分布表现为东高西低的形势,垂直纬向平均分布表现为暖水厚度和温跃层深度东厚(深)西薄(浅),垂直经向平均表现为暖水厚度南厚北薄,温跃层深度中间浅两边深;南海地区海温变化幅度在75~200 m处最大,不同深度海温距平均具有明显的年际和年代际变化特征;南海区域平均热含量在秋季最高,春夏次之,冬季最低,其年际变化明显,且在1998年之后出现明显的突变,由负值转变为正值,表现出明显的增温趋势;热含量季节EOF主模态空间分布形势表现为东高西低的特征,对应的时间序列在20世纪90年代末存在年代际转折,由主要为负值转化为主要为正值,表现在空间分布上,则为南海地区热含量由西高东低型转化为东高西低型。  相似文献   

6.
陇南山区乡村聚落空间格局研究   总被引:1,自引:1,他引:0  
解决好山区乡村问题对建设小康社会和实现全面发展具有重要意义。文章基于景观格局指数,以陇南市为研究对象,借助ArcGIS、GeoDa空间分析工具,从数量、规模、形态、邻近度出发,探索了山区乡村聚落在不同空间尺度上的分布特征。结果表明:(1)陇南市独院和小型聚落数量庞大,占乡村聚落总数的79.25%,大、中型聚落数量相对较小,但面积占乡村聚落总面积的79.66%;(2)西和县的中西部和徽县的中部是单位土地面积上乡村聚落数量和面积高值出现的热点区;(3)陇南市乡村聚落规模在东西方向上呈现“中部较东西两侧大,东部略大于西部”的特点,在南北方向上呈现“自南向北缓慢增加”的特点;(4)陇南山区最西端有一个狭小的聚落形态规整带,其余地方乡村聚落的形态普遍不规整;(5)陇南山区乡村聚落形状指数存在高值与高值聚集、低值与低值聚集的特点;(6)陇南市乡村聚落的土地利用集约水平较高,聚落显著聚集的村有1937 个,占全市行政村个数的61.16%,并且显著聚集的村在空间上集中分布。  相似文献   

7.
洛南县连翘种植区土壤养分状况及空间分布特征初步研究   总被引:1,自引:1,他引:0  
揭示洛南县土壤养分空间变异规律,为指导该县连翘种植科学施肥和服务精准农业提供技术支撑。本研究采用地理信息技术和地统计学原理,在土壤样品信息采集的基础上,探讨分析该县土壤养分状况和主要养分指标空间变异趋势。研究表明:洛南连翘种植区土壤pH值多为中性;有机质整体较缺乏,尤以东南部地区缺乏明显;氮素从北到南呈减少趋势,东南部地区含量较缺乏;速效磷为适宜水平,从西向东呈减少趋势,自南向北呈增加趋势;速效钾含量较高,从西向东、自南向北呈增加趋势;微量元素有效含量中铁较丰富,锰、铜、锌处于适宜水平,硼较缺乏。研究结果可供布局连翘种植基地及连翘种植合理施肥参考。  相似文献   

8.
The smart low-carbon development of modern cities has become one of the academic hotspots.However,the dynamics is rarely involved.Therefore,TOPSIS method was used to take a quantitative study on the dynamics of smart low-carbon development for major Chinese cities.The results showed that:(1) 3 main dynamics of smart lowcarbon city development in China are institution and culture conditions,facility and function conditions and economy and industry conditions,but the overall utility is relatively low;(2) the level of dynamic operation mechanism of smart low-carbon development for major Chinese cities is distinct between regions,indicating a spatial law of diminishing from the east to the west and differing within regions;(3) the imbalance of comprehensive dynamic mechanism and operation state between major cities is prominent,showing an urban scale law of decreasing from big to small and differing within each scale and an administration hierarchy law of descending from high to low and differing within each class;(4) 7 basic development patterns can be obtained,and most of the cities take the external strong internal weak mode,which basically matches with its development realities.  相似文献   

9.
Revitalization of waterfront-a precious resource of city has gradually become popular worldwide. Cities around the Three Gorges Reservoir grow and proper for the Yangtze River,thus waterfront in these cities has been long ignored or faced with "constructive destruction" with the city development. This paper divided urban waterfront public spaces around the Three Gorges into 3 kinds of spaces,namely point,line and surface,from the perspective of typology,and put forward strategies such as functional renovation,and improvement of spatial scale from the perspectives of land use and traffic,to enhance the vitality of waterfront public space.  相似文献   

10.
The pledge of stock rights is a method for measuring the external horizontal connections of enterprises, which is more suitable to represent the city network compared with the vertical connections of enterprises. Meanwhile, it is greatly significant to express the relationships of regional spaces. The paper characterizes and explores the evolution of urban spatial structure with complex network research methods to enrich the relevant works on city networks in the Yangtze River Economic Belt from 2011 to 2017. The results are as follows: First, from 2011 to 2017, the pledge of stock rights among cities was enhanced significantly, and the trend of the city networks' characteristics become strengthened and more complicated. Second, cities in the Yangtze River Delta have relatively high connection values, however, cities in the western area are holding peripheral positions within the city network. Third, due to the advantages of economic agglomeration and radiation, the provincial capital have become the core nodes in the city network. Fourth, Shanghai, Hangzhou, and Nanjing have dominant positions within city networks in the Yangtze River Economic Belt. Particularly, Shanghai, as one of the leading financial centers in China, has a growing influence on other cities and gradually evolved into a regional growth pole city and the first core city.  相似文献   

11.
Coal cities are the main part of the resource-based cities in China, and the benign development of coal cities' spatial structure has a direct impact on these cities' future economic and social development, as well as the urban residents' welfare. Land use fragmentation is the most typical morphological characteristic of the coal city's spatial structure development. In this paper, Pingdingshan City of Henan Province in China is taken as an example. Through empirical analysis, the urban spatial structure development processes of a typical coal resource-based city in its mature period are illustrated, and the formation reasons and potential mechanism behind coal city land use fragmentation are explored, and the measurement method of land use fragmentation degree of the coal city is put forward. On the above basis, the appropriate adjustment strategies and methods aimed at the coal city spatial structure are found out and given. This study is a good guideline and reference for the spatial structure planning and land use planning of the coal city during the mature and declining period, which is of great help to the sustainable development and industrial structure transformation of the coal city. It also has certain reference significance for the coal city in the growth period.  相似文献   

12.
Classical Chinese garden is a compound artwork of material and spiritual construction,and Xishu Garden is a regional product with outstanding characteristics and high quality among classical Chinese gardens,it has special spiritual construction and outstanding regional characteristics.Regional cultural characteristics of Xishu garden are analyzed from the perspectives of philosophy consciousness,spirit of history and comprehensive art,especially the gardening view based on Taoism,memorial significance,spirit of history and style it inherits from the Tang and Song Dynasties.Enlightenment of Xishu Garden on modern landscape architecture is elaborated.  相似文献   

13.
Located in the east of Xi'an, Dongguan District is the area to the east of the Ming City wall.There is a great deal of precious architectural heritages in the area, including shrines such as the Wangji Temple, the Baxian Temple, the Catholic Church and the Laomu Temple, as well as protected dwellings such as the Xingqing Palace, the royal palace of the flouring period of the Tang Dynasty, and the Courtyard of Family Xi, etc.. Currently, securing Dongguan District protection and development has confronted with severe challenges. Based on the in-depth investigation of the status quo and objective analysis of pros and cons, this paper gives a clear definition for Dongguan District protection and development, and profoundly analyses courtyards, streets, landscape environment and human environment of the Dongguan District, so as to formulate protective methods as well as measures and explore development approaches.  相似文献   

14.
为了计算出近年辽宁省日光温室这种特殊几何屋面建筑所受的基本雪压及雪荷载分布情况,利用辽宁省30年冬季降水数据,使用矩法、耿贝尔参数估计方法对极值I型分布函数的参数进行估计,比较参数优良性指标,进而计算30年一遇最大降雪量及基本雪压,结合辽宁省日光温室结构特点,确定日光温室积雪分布系数,最终得出辽宁省各地区日光温室雪荷载分布。结果表明:辽宁省30年重复期实际基本雪压与建筑规范中基本雪压标准值差距较大;辽宁省日光温室雪荷载范围为0.28~0.79 kN/m2。其中,以鞍山、岫岩、本溪、沈阳等中部地区雪荷载最大,由此向东西南北4个方向雪荷载逐渐减小。  相似文献   

15.
大风在地表裸露的沙尘源地及其附近形成沙尘暴灾害,使土壤风蚀、沙化,增加沙尘频次和恶化空气质量,破坏生态环境,危害农业生产。因此,深入研究生态环境相对脆弱的新疆地区的极大风速风向特征,对于防灾减灾,治理活化沙丘及实现本区的可持续发展具有十分重要的意义。本文以新疆地区71 个站点的最新资料为基础, 探究新疆地区1993—2013年极大风速的时间演变现象和空间分布特征,给出新疆地区年、月极大风速出现日数的分布及风速方向特征。得出,1993-2013年间乌恰县风速大于17m/s的日数最多,和田市最少;总共16天。极大风速日数最高值出现在1999年,全疆总大风日为257天;最低值在2013年,全疆总大风日为69天。春夏季大风如数大于秋冬季。新疆主要城县极大风速方向有明显差异,天山以东主要为东南、东北方向;天山以北主要为西北、东北方向;天山以南主要为东北、西北方向;天山以西主要为东南、西北方向。  相似文献   

16.
刘毅  庞玥  陈鹏  刘超 《中国农学通报》2016,32(27):149-155
利用1981—2010年重庆市34个气象观测站的日(20时—20时)降水量资料及空间间隔为2.5°×2.5°的NECP/NCAR逐6小时再分析资料,对重庆西部区域性阻塞型暴雨天气过程进行统计合成分析,结果表明:(1)导致渝西阻塞型暴雨的大尺度环流背景场为稳定的“两槽一脊”型环流,贝加尔湖低槽与东移的四川盆地低槽同位相叠加,副高西伸并稳定维持,位势场呈现“西低东高”的特点;(2)来自于南海地区的水汽持续输送至重庆西部地区为暴雨过程的产生和维持提供了有利的水汽条件;(3)暴雨发生前后温湿场发生了明显变化,温度场上暴雨发生前和发生时暴雨区附近有着较强的暖平流,而暴雨发生后为明显冷平流,湿度场上700hPa上10g/kg等比湿线及850hPa上15g/kg等比湿线可作为渝西阻塞型暴雨的一个预报参考指标。  相似文献   

17.
城郊公路边菜田土壤和韭菜中重金属的空间变异特征   总被引:1,自引:0,他引:1  
采用传统统计和地统计相结合的方法,对70hm^2城郊公路边莱田土壤和韭菜中重金属空闯变异特征进行了研究。结果表明,土壤Cu,Zn,Pb和Cd总量一般随距公路距离的增加呈降低的趋势,但其含量均未达到对土壤和作物构成潜在威胁的二级超标水平。韭菜可食部分Pb含量总体上也随距公路距离的增加呈降低的趋势,距南边公路往北280m和距西边公路往东90m范围内韭菜可食部分Pb含量普遍超标。韭菜可食部分Pb含量普遍超标主要与土壤中Pb含量和韭菜叶片吸收尾气Pb有关;自南边公路往北和自西边公路往东韭菜可食部分Pb含量空间变异的差异,可能与树木遮挡差异对尾气Pb运动影响范围的不同有关。  相似文献   

18.
江西近55年秋季降水时空分布及异常环流特征分析   总被引:1,自引:0,他引:1  
为了研究江西近55年秋季(9—11月)降水的时间空分布及其异常环流形势特征,利用1961—2015年共55年86个气象站逐日降水资料及NCEP/NCAR月平均再分析资料,采用EOF、REOF分析、Morlet小波分析、趋势分析、M-K突变检验和合成分析等方法,研究江西近55年秋季降水的时间变化规律、空间分布特征及旱涝年的环流特征。结果表明:近55年来江西秋季降水呈弱增长趋势,在1981年、1984年和1987年发生突变,存在12~14年和2~4年的周期。空间场可分为全省一致型,南—北相反型和南北—中部相反型,其中全省一致型为主要空间分布形式。江西秋季降水可分为5个区域:一区(赣北中西部)、三区(赣中西部)和五区(赣中中东部)秋季降水呈增多趋势,二区(赣南)秋季降水呈减少趋势;四区(赣东北)秋季降水变化趋势较为稳定。5个区域秋季降水都存在2~4年左右的周期变化,还有多个区域都存在4~6年左右的周期变化,最长周期为14年左右。此外,江西秋季旱年,欧洲东部500 h Pa的大槽加强,江西850 h Pa处东北风距平中,降水偏少;反之,降水偏多。  相似文献   

19.
Eco-efficiency is an important indicator which serves as a helpful instrument for the studies of sustainable development. This paper estimated the eco-efficiency of 26 cities in China's Yangtze River Delta urban agglomerations. Based on different matrixes, Moran's I was applied to analyze the spatial correlation. The spatial Durbin model was applied to analyze the direct and indirect effect of influencing factors. Some conclusions were drawn. (a) The average eco-efficiency showed an increasing trend. The regional difference of eco-efficiency decreased and then increased. Shanghai's eco-efficiency had been the highest. (b) The eco-efficiency showed positive spatial autocorrelation and it also exhibited significant characteristic of local spatial autocorrelation. (c) Economic development, fixed assets investment, and technological level of one city had a significant positive impact on the eco-efficiency of the city itself. Industrial structure, fiscal decentralization, and foreign direct investment of a city had a significant negative impact on the eco-efficiency of the city itself. Changes in the economic development and technological levels in a city had positive impacts on the eco-efficiency of its neighboring cities. Foreign direct investment had a negative spatial spillover effect. (d) This paper suggested that it is necessary to pay attention to the interaction of influencing factors among cities.  相似文献   

20.
东北地区夏季降水和气温时空分布特征   总被引:3,自引:3,他引:0  
为了研究东北地区夏季降水和气温的时空分布特征,基于1951—2012年国家气候中心提供的160站月降水及气温资料,利用经验正交函数分析方法及小波分析方法对东北地区的降水、气温场的时空分布特征进行诊断分析。结果表明:东北地区夏季降水量场主要表现为全区一致型、南北差异型、东西差异型及中部差异型,东北地区气温场主要表现为全区一致型及南北差异型,且均存在明显的震荡变化。东北地区夏季降水及气温存在显著不同的多时间尺度振荡周期,降水量存在29年的主周期,气温存在28年的主周期。  相似文献   

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