Ghost city extraction and rate estimation in China based on NPP-VIIRS night-time light data

The ghost city phenomenon is a serious problem resulting from the rapid urbanization process in China. Estimation of the ghost city rate (GCR) can provide information about vacant dwellings. This paper developed a methodology to quantitatively evaluate GCR values at the national scale using multi-resource remote sensing data. The Suomi National Polar-Orbiting Partnership–Visible Infrared Imaging Radiometer (NPP-VIIRS) night-time light data and moderate resolution imaging spectroradiometer (MODIS) land cover data were used in the evaluation of the GCR values in China. The average ghost city rate (AGCR) was 35.1% in China in 2013. Shanghai had the smallest AGCR of 21.7%, while Jilin has the largest AGCR of 47.27%. There is a significant negative correlation between both the provincial AGCR and the per capita disposable income of urban households (R

Advances in Green Infrastructure Planning

The expansion of urban areas has facilitated the conversion of undeveloped lands, which has led to environmental degradation, such as loss of habitats, hydro-modification, and the collapse of existing ecosystems. Recent climate change has exacerbated these damages by causing more frequent and serious hazards. To attenuate the impacts of urbanization and the negative effects of climate change, green infrastructure (GI) planning (e.g., nature-based strategies, technologies, policies, and solutions) has arisen as an important approach for balancing urban development and nature. GI offers a variety of benefits to our cities by reducing stormwater runoff, heat waves, and air pollution; expanding wildlife habitats; and increasing recreational opportunities and even nearby property values

The Impact of Online Real Estate Listing Data on the Transparency of the Real Estate Market - Using the Example of Vacancy Rates

Despite the increasing digitization of the real estate market and the accompanying greater availability of data, as evidenced, for example, by the proliferation of online real estate listing platforms, there are still deficiencies in market transparency associated with a variety of negative aspects. This study aimed to investigate the impact of online real estate listing data on market transparency by examining the suitability of these data for scientific use in general and for the example of estimating vacancy rates in particular. Therefore, a comprehensive data set consisting of more than seven million listings was collected over one and a half years and analyzed with regard to all available features in terms of their quality and quantity. Furthermore, their explanatory power for estimating vacancy rates was tested by their application in different regression models. The features specified in online real estate listings showed an average completeness of 85.97 % and, most widely, plausible feature specifications. Exceptions were information regarding energy demand, which were only available in 20.79 % of listings, and the specification of the building quality and condition, which showed indications of being positively biased. The estimation of vacancy rates on the district level, based on online real estate listing data, showed promising results, being able to explain vacancy rates with a goodness of fit of a pseudo R² of 0.81 and a mean absolute error of 0.84 percentage points. These results suggest that information contained in online real estate listing data are a good basis for scientific evaluation and are specifically well suited for estimating vacancy rates. The findings imply the utilization of online real estate listing data for a diverse range of purposes, extending beyond the current focus of price-related research

Identifying Population Hollowing Out Regions and Their Dynamic Characteristics across Central China

Continuous urbanization and industrialization lead to plenty of rural residents migrating to cities for a living, which seriously accelerated the population hollowing issues. This generated series of social issues, including residential estate idle and numerous vigorous laborers migrating from undeveloped rural areas to wealthy cities and towns. Quantitatively determining the population hollowing characteristic is the priority task of realizing rural revitalization. However, the traditional field investigation methods have obvious deficiencies in describing socio-economic phenomena, especially population hollowing, due to weak efficiency and low accuracy. Here, this paper conceives a novel scheme for representing population hollowing levels and exploring the spatiotemporal dynamic of population hollowing. The nighttime light images were introduced to identify the potential hollowing areas by using the nightlight decreasing trend analysis. In addition, the entropy weight approach was adopted to construct an index for evaluating the population hollowing level based on statistical datasets at the political boundary scale. Moreover, we comprehensively incorporated physical and anthropic factors to simulate the population hollowing level via random forest (RF) at a grid-scale, and the validation was conducted to evaluate the simulation results. Some findings were achieved. The population hollowing phenomenon decreasing gradually was mainly distributed in rural areas, especially in the north of the study area. The RF model demonstrated the best accuracy with relatively higher R2 (Mean = 0.615) compared with the multiple linear regression (MLR) and the geographically weighted regression (GWR). The population hollowing degree of the grid-scale was consistent with the results of the township scale. The population hollowing degree represented an obvious trend that decreased in the north but increased in the south during 2016–2020 and exhibited a significant reduction trend across the entire study area during 2019–2020. The present study supplies a novel perspective for detecting population hollowing and provides scientific support and a first-hand dataset for rural revitalization

都市縮小に伴う空き家と交通システムの効率化に関する研究

近年、空き家は多くの国にとって大きな課題の1つになっている。 2018年の日本の空き家総数は849万戸に達し、総住宅ストックの13.6％を占める。 OECD諸国と比較して、この数字は最も高く、社会の高齢化と低い出生率により、将来さらに増加すると予想されている。住宅市場を安定させるためには、空き家の比率を一定の水準、通常は5％未満に抑える必要がある。実際の空室率がこのしきい値を超えると、需給関係の不均衡を反映するだけでなく、都市の持続可能な開発に様々な悪影響を与える可能性がある。これらの悪影響としては、近隣の不動産の価値の低下、空室率と犯罪率の増加の刺激、劣悪な衛生状態と景観、税収の減少、および輸送システムの非効率的な運用が含まれる。したがって、空き家の発生のメカニズムを理解し、その影響を制御することが不可欠となる。これらの問題を解決するために、本研究は以下の2点を目的とする。まず、空き家とその決定要因の空間分布状況を調査する。次に、住宅利用との関係における輸送システムの効率性を評価する。これらの目的のケーススタディとして、北海道札幌市を選定した。分析手法として、局所空間的自己相関分析、部分最小二乗回帰（PLSR）、およびデータ包絡分析（DEA）を適用することにより、研究の目的を達成する。分析の結果は、高い住宅空室が中央地区と密集した地域に集中する可能性が高いことを強く示した。空室レベルは、市内中心部までの距離が長くなるにつれて減少する傾向にある。空き家に影響を与える特徴の中で、人口統計学的特性が最も強力な決定要因となった。その中でも、空き家を促進する影響として、単身世帯数属性が他の世帯の属性を上回った。同様に、人口の減少に伴う住居の供給過剰は、空室の増加に集中的な影響を及ぼしていた。対照的に、住宅所有率の増加と建物内の統合駐車場は、空き家の数を減らすことが分かった。また、DEAの分析によると、札幌市、特に駐車場やエリアの交通サービスの余剰は、住宅の充填率の不足によるものであった。研究成果は、研究論文としてだけでなく、持続可能な開発を達成するための政策立案にも貢献すると考えられる。In recent years, vacant houses have become one of the major challenges for many countries. In 2018, the total number of vacant houses in Japan reached 8.49 million units, accounting for 13.6% of the total housing stock. Compared to OECD countries, this figure was the highest and was expected to further increase in the future due to social aging and the low fertility rate. For a stable housing market, it is necessary to keep the ratio of the unoccupied dwellings within a certain level, usually less than 5%. When the real vacancy rate exceeds this threshold, it may not only reflect the imbalance in the supply-demand relationship but also negatively affect the sustainable development of the urban. These negative influences include the neighbouring properties’ value reduction, stimulation of the increased vacancy and crime rates, poor sanitation and landscape, decline in tax revenue, and the inefficient operation of the transportation system. Therefore, it is essential to understand the mechanism of vacant dwellings occurrence and to control its effects. To solve these problems, this study aims at two points. First, it examines the spatial distribution of vacant houses and their determinants. Second, it evaluates the transportation system’s efficiency in the relationship to housing utilization. The city of Sapporo, Hokkaido, was chosen as a case study for these objectives. By conducting the local spatial autocorrelation analysis, partial least squares regression (PLSR), and data envelopment analysis (DEA), the study’s objectives are achieved. The results highlight that the high housing vacancy would likely concentrate in the central district and the dense areas. The vacancy level then decreases with the increase in the distance to the city’s center. Among the affecting features, the demographical characteristics were the strongest determinants. In which, the number of single households outperformed the other in stimulating the vacant houses. Likewise, the oversupply of dwellings along with the decline of the population had an intensive effect on the rise of vacancy. By contrast, the increase in the housing ownership ratio and the integrated parking lots in the buildings would reduce the number of vacant dwellings. Moreover, the DEA analysis shows that the shortfall in the housing filling rate accounted for the surplus in transportation services in the city of Sapporo, especially the car parking sites and areas. The outcomes of the study would contribute to not only the literature but the policy-making in achieving sustainable development.室蘭工業大学 (Muroran Institute of Technology)博士（工学

CITIES: Energetic Efficiency, Sustainability; Infrastructures, Energy and the Environment; Mobility and IoT; Governance and Citizenship

This book collects important contributions on smart cities. This book was created in collaboration with the ICSC-CITIES2020, held in San José (Costa Rica) in 2020. This book collects articles on: energetic efficiency and sustainability; infrastructures, energy and the environment; mobility and IoT; governance and citizenship

The Demography of Disasters

This open access book provides worldwide examples demonstrating the importance of the interplay between demography and disasters in regions and spatially. It marks an advance in practical and theoretical insights for understanding the role of demography in planning for and mitigating impacts from disasters in developed nations. Both slow onset (like the of loss polar ice from climate change) and sudden disasters (such as cyclones and man-made disasters) have the capacity to fundamentally change the profiles of populations at local and regional levels. Impacts vary according to the type, rapidity and magnitude of the disaster, but also according to the pre-existing population profile and its relationships to the economy and society. In all cases, the key to understanding impacts and avoiding them in the future is to understand the relationships between disasters and population change. In most chapters in this book we compare and contrast studies from at least two cases and summarize their practical and theoretical lessons

Towards Socially Integrative Cities

This book is based on the results of the TRANSURBAN-EU-CHINA project. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 770141. The material presented in this book reflects only the authors' views. It does not reflect the official opinion of the European Commission. The TRANS-URBAN-EU-CHINA project or the European Commission are not liable for the contents of the chapters or any use that may be made of the information contained therein. About The book Towards Socially Integrative Cities deals with the transition towards urban sustainability through socially integrative cities in Europe and China. It shares the impactful original research results of an EU-funded R&I project involving eight European and six Chinese partners (TRANS-URBAN-EU-CHINA; see www.transurbaneuchina.eu). Three each of the six editors come from European and Chinese universities and research institutions. The first articles (No. 1–4) provide an overview and insights into the conceptual basis of the book. The socially integrative city is framed by discussions in academia and practice, and it is defined in a comprehensive way as an element of urban sustainability. Sustainability transitions in China are linked to international discussions and the challenges are articulated. Moreover, the discussions touch on the strengths and weaknesses related to managing urban growth and the rapid expansion of cities. Land development tools are discussed with regard to the opportunities they offer for creating socially integrative cities. A second set of articles (No. 5–9) focus on socially integrative urban regeneration of cities. After an overview of policies and strategies in Europe and China, detailed aspects are discussed, such as community building through public engagement, challenges of place-making, and the role of education and life-long learning. Finally, a manuscript on heritage preservation and its impact on social integration in urban regeneration concludes this section. A third set of articles (No. 10–13) look into issues of the transformation of cities and sustainability transitions. Transformation is understood as a complex set of interactions. The development of tools, such as community platforms for information and dialogue transfer, are discussed as an instrument to facilitate transition processes. The transformative capacity of cities in Europe and China is discussed in an article that looks into possibilities to narrow the gaps between urban planning and development. Smart and eco-cities in Europe and China are taken as an empirical base. Advanced methods, such as the Social Cost–Benefit Analysis, may support social integration. Finally, an example of how the use of multiple data sources can speed up the digital transition in cities and provide decision support for social integration is presented. The final set of articles (No. 14 and 15) deal with questions of replicability of experiences and the role of concrete urban experiments in so-called Urban Living Laboratories. Methods to explore the replication potential of urban solutions for socially integrative cities are discussed. Finally, the potential of urban living laboratories for nurturing open urban innovation in Chinese cities is scrutinized. Several examples are discussed, and conclusions regarding the enhancement of social integration in cities are drawn. The book is edited by Bernhard Müller (Technische Universität Dresden, TUD), Baojun Yang (China Academy of Urban Planning and Design, CAUPD), Liu Jian (Tsinghua University), Jianming Cai (China Academy of Sciences, CAS), Paulina Schiappacasse (TUD) and Hans-Martin Neumann (Austrian Institute of Technology, AIT)