• Energy Research

Mountainous settlements accommodate nearly one tenth of the world’s population. Most mountainous cities have adopted the strategy of polycentric urban development due to an asymmetric geography, which has received little attention from mainstream research. To fill the research gap, we proposed an analytical framework and conducted a multi-dimensional measurement of polycentricity. Taking Chongqing for the case study, this work confirmed that polycentricity is morphological and functional in mountainous cities. Polycentricity is believed to be particularly applicable to mountainous and water-rich landscapes, leading to an appropriate, balanced distribution and the strong multi-directional connectivity of urban nodes. This characteristic may partly result from natural determinism and long-term planning adaptation, complementary to market forces. Policy implications for planning such as avoiding excessive encroachment on natural barriers and increasing functional linkage in newly established subcenters were also proposed.

In this paper, metabolic evaluation has been employed for better understanding the trends in urban environmental changes. Due to the urban activities cause impacts not only on local level but also a broader scale, Hybrid Emergy-LCA (HEML), a combining approach of Emergy Analysis (EMA) and Life Cycle Assessment (LCA) is structured to quantitatively investigate the mechanism. For the similarity across many emerging cities in China, a large-scale sub-urban residential area named Tian Tongyuan (Try) in Beijing was chosen for testing the HEML. Objective indicators of live quality and negative impacts are both considered. Analysis indicates that the household Emergy input of TTY is 1.76E+16 sej/yr, while the prominent environmental impact is induced by Photochemical Oxidant Creation Potentials (POCP), 4.58E+05 g ethane eq./yr. The sustainable performance constructed by its live quality and environmental impacts of TTY is found as 98.80% as that of Beijing average. Mitigation polices on the building sector should be proposed because of its dominating impacts among various consuming ends of energy and materials. (C) 2009 Elsevier B.V. All rights reserved.

Together with the emerging popularity of big data in numerous studies, increasing theoretical discussions of the challenges and limitations of such data sources exist. However, there is a clear research gap in the empirical comparison studies on different data sources. The goal of this paper is to use “attractiveness” as a medium to examine the similarity and differences of Social media data (SMD) and survey data in academic research, based on a case study of the Beijing Olympic Forest Park, in Beijing, China. SMD was extracted from two social media platforms and two surveys were conducted to assess the attractiveness of various locations and landscape elements. Data collection, keyword extraction and keyword prioritization were used and compared in the data gathering and analysis process. The findings revealed that SMD and survey data share many similarities. Both data sources confirm that natural ambience is more appreciated than cultural elements, particularly the naturalness of the park. Spaces of practical utility are more appreciated than facilities designed to have cultural meanings and iconic significance. Despite perceived similarities, this study concludes that SMD exhibits exaggerated and aggregated bias. This resulted from the intrinsic character of SMD as volunteered and unstructured data selected through an emotional process rather than from a rational synthesis. Exciting events were reported more often than daily experiences. Reflecting upon the strength and weakness of SMD and survey data, this study would recommend a combined landscape assessment process, which first utilizes SMD to build up an assessment framework, then applies conventional surveys for supplementary and detailed information. This would ultimately result in comprehensive understanding.