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31.
《Cities》2014
Socio-spatial differentiation and residential segregation have been studied extensively in numerous cities and have contributed significantly to the understanding of urban spatial and social structures. Analyses of diverse data sets at varied spatial scales have supported the development of theoretical frameworks. However, the majority of Chinese case studies published in recent decades were dominantly based on either non-spatial data or population census data at sub-district (or jiedao in Chinese) level. These analyses have been limited through using low-resolution aggregate data resulting in incomplete or biased findings. This paper aims to examine the fine-scale socio-spatial structure of the inner city of Nanjing using the fifth population census data of 2000 at the lowest spatial scale – community (or juweihui in Chinese) level. Our findings reveal that the policies of the socialist era and the initial outcomes of the introduction of a free market, particularly with regard to the creation of new elite spaces within the inner city, have shaped a complex pattern of socio-spatial differentiation and residential segregation. 相似文献
32.
The EU-27 residential building stock offers high potential for energy efficiency gains. The policies already in place or proposed to improve the energy efficiency and thus the environmental performance focus on new buildings and major renovations of existing buildings. However, there might be additional measures that could lead to further energy efficiency improvements. In particular, the installation of roofs or windows that show a high thermal efficiency outside major renovations offer a large improvement potential. In this study, the potential environmental and economic impacts of two types of such policy options were analysed: first, measures that require high energy efficiency standards when roofs or windows have to be replaced; and, second, measures that accelerate the replacement of building elements. The results suggest that the two policies offer the potential for substantial additional energy savings. In addition, the installation of energy efficient building elements comes at negative net cost. When the replacement of building elements is accelerated, however, the additional costs do not outweigh the energy cost savings. 相似文献
33.
Building envelope impacts upon energy consumption and indoor environment. The relationship between envelope components and indoor environment has become increasingly important, especially with the new emphasis on visual comfort, thermal comfort and indoor air quality. This paper examines the interaction between occupant thermal comfort and envelope component regulations in the Gulf States. The country chosen for this study is the Kingdom of Bahrain, the smallest country in the Gulf region. Simulation results and comparative studies were employed to investigate the impact of the current envelope component regulations on the internal environment. The paper focuses on residential buildings and concludes that the envelope component regulations contribute positively to the internal thermal performance. Although these envelope components are not generally the primary elements that impact upon internal thermal comfort there are circumstances when the components become very warm and occupants positioned close to them will experience discomfort. This paper shows that the thermal insulation regulation makes a small impact on thermal comfort, whereas the window regulation, particularly glazing, is more influential and that for most window areas, solar impacts are generally large. 相似文献
34.
The influence of combined alignments on lateral acceleration on mountainous freeways: a driving simulator study 总被引:1,自引:0,他引:1
Combined horizontal and vertical alignments are frequently used in mountainous freeways in China; however, design guidelines that consider the safety impact of combined alignments are not currently available. Past field studies have provided some data on the relationship between road alignment and safety, but the effects of differing combined alignments on either lateral acceleration or safety have not systematically examined. The primary reason for this void in past research is that most of the prior studies used observational methods that did not permit control of the key variables. A controlled parametric study is needed that examines lateral acceleration as drivers adjust their speeds across a range of combined horizontal and vertical alignments. Such a study was conducted in Tongji University’s eight-degree-of-freedom driving simulator by replicating the full range of combined alignments used on a mountainous freeway in China. Multiple linear regression models were developed to estimate the effects of the combined alignments on lateral acceleration. Based on these models, domains were calculated to illustrate the results and to assist engineers to design safer mountainous freeways. 相似文献
35.
虽然目前控制性详细规划中容积率等指标的核算有多种手段,但很少有基于实验的演算型定量研究。针对不同大小的基地,均可通过实验,推算日照标准约束下的容积率等指标,作为规划决策的重要依据。从当前日照标准约束角度,提出运用空间极限容积率校核的实验方法,通过计算机实验进行核算。提出了基于"九宫格"的计算方法,经过少量人工干预,由计算机生成指标对应的空间形态,以使控制性详细规划指标的确定更加科学、理性。实验表明,如果日照标准约束条件不变,容积率并不是可以随着住宅高度的增加而无限增加。如果需保证一定的日照资源质量,住宅高度和容积率存在增长极限。 相似文献
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论文基于地域性风景园林美学研究的视角,就当代江苏居住区景观环境艺术特征进行归纳分析,认为其在依托自然环境、传承居住文化、延续地方特色、塑造丰富空间等方面具有鲜明的特色,体现的是一种整体的环境观与艺术观,并且呈现出由"和谐"向"美丽"发展的鲜明动势。 相似文献
38.
本文从阐述山地城市的概念出发,总结山地城市的特点,而后根据山地城市的特点及竖向上的难点,从现状分析、道路交通规划、竖向设计手法、工程防护、场地排水和土石方工程等六个方面对山地城市的竖向规划方法进行分析和研究,并对竖向规划过程中需注意的要点进行疏理和归纳。 相似文献
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