News

RILS develops deep learning-based remote sensing image classification for land use land cover mapping in cloud-prone areas

Prof. Qihao WENG, Associate Director of the Research Institute for Land and Space (RILS) and his team have developed an integrated time series mapping method to enhance the land use and land cover (LULC) mapping accuracy and frequency in cloud-prone areas. Other key PolyU members on the research team include Prof. Xiaoli DING, Director of RILS, and Dr Zhiwei LI, Research Assistant Professor in the Department of Land Surveying and Geo-Informatics. The method incorporates spectral-indices-fused deep learning models and time series reconstruction techniques. The team applied the method to the cloud- and rain-prone Pearl River Delta (i.e., Guangdong–Hong Kong–Macao Greater Bay Area, GBA), and yielded an overall mapping accuracy of up to 87.01%, outperforming existing LULC products. This method has the potential to generate seamless and near real-time maps for different regions in the world by using deep learning models trained on datasets collected globally. It can provide high-quality LULC data sets at different time intervals for various land and water dynamics in cloud- and rain-prone regions.   Read the full paper: https://shorturl.at/jyj1B

RILS scholars win two Smart Living Partnership Awards 2023/24

Congratulations to Prof. Xiaoli DING, Director of the Research Institute for Land and Space (RILS), and Dr Wallace LAI, core Member of RILS, for winning the awards “Outstanding Land Subsidence Monitoring Technology by Integrating Satellite Remote Sensing & Mobile Surveying” and “Outstanding Imaging Technologies for Rapid Leakage Diagnosis of High-Pressure and Large Water Mains” respectively, in the Smart Building / Environment Technology / Green Technology category of the Smart Living Partnership Awards 2023/24.   Co-organised by ETNet and Hong Kong Cyberport, the Award aims to recognise, promote and support outstanding companies or organisations which demonstrate commitment to promoting Hong Kong as a Smart City, improving the society’s competitiveness and increasing public awareness of digitalisation.   Online coverage: ETNet - https://polyu.me/4e0Kw94 Anue - https://polyu.me/3UVQmju

ADoRILS develops deep learning-based super-resolution method for building height estimation

A study by Prof. Qihao WENG, Associate Director of the Research Institute for Land and Space (RILS), Director of Research Centre for Artificial Intelligence in Geomatics, Member of the Otto Poon Charitable Foundation Smart Cities Research Institute (SCRI) and Chair Professor of Geomatics and Artificial Intelligence, and his research team, titled “A deep learning-based super-resolution method for building height estimation at 2.5 m spatial resolution in the Northern Hemisphere” was recently published in the journal Remote Sensing of Environment.   Building height is an important indicator for assessing the level of urban development along the vertical dimension. Existing large-scale building height estimation studies focusing on coarse spatial resolution cannot reveal height variations across buildings in urban areas.   The team proposed a deep learning-based super-resolution method to generate building height maps. The researchers created an open building height dataset with 45,000 samples covering 301 cities in the Northern Hemisphere, including China, the conterminous United States, and Europe. The dataset generated provides great potential in high-resolution database updating, urban planning, and natural disaster assessment, as well as a new perspective of how cutting-edge satellite imaging technology can be utilised in urban observation, measurement, monitoring, and management.   Read the full paper: https://www.sciencedirect.com/science/article/pii/S0034425724002591

PolyU study reveals effectiveness of GBGI infrastructure in mitigating urban heat

Prof. Hai GUO, Management Committee Member of the Research Institute for Land and Space (RILS) and Professor in the Department of Civil and Environmental Engineering, together with global researchers, have conducted a first-of-its-kind study on the effectiveness of green-blue-grey infrastructure (GBGI) in cooling urban heat across various regions. The study findings have been published in the international interdisciplinary journal The Innovation.   The study revealed regional and city-specific variations in the effectiveness of GBGI for mitigating urban heat. In Europe, Asia, North America and Australia, the overall cooling effect of GBGI is up to 18.9°C, 17.7°C, 12°C and 9.63°C respectively. In addition, the implementation of green and blue infrastructures has proven to be highly effective in lowering air temperatures globally. While green infrastructures can regulate urban heat through evaporation, transpiration, shading and thermal insulation, blue infrastructures absorb heat and cool the surrounding area through evaporation.   The study also showed notable effects of various GBGI features in mitigating urban heat in Mainland China cities. The most effective means include botanical gardens, wetlands, green walls and attenuation ponds which exhibited temperature reductions of up to 10°C, 9.27°C, 8°C and 7°C respectively. Although the cooling effect ranges are generally similar in the north and south of China, there is variability within the same region. For example, in Beijing, botanical garden could result in up to 10°C temperature decrease while that in Shaanxi province only contributed to 2.7°C. In Hong Kong, parks, green roofs and golf courses were found to play substantial roles in cooling urban heat, resulting in temperature reductions of 4.9°C, 4.9°C and 4.2°C respectively.   Press release: https://polyu.hk/BqOJh Read the full paper: https://www.sciencedirect.com/science/article/pii/S2666675824000262?via%3Dihub Online coverage: Sing Tao Daily - https://polyu.me/4bbXhvP Sing Tao Headline - https://polyu.me/4bYufjt Ta Kung Pao - https://polyu.me/3K1bUGq Dot Dot News - https://polyu.me/3UIActC Xinhua Finance Agency - https://polyu.me/3K719Cg Hong Kong China News Agency - https://polyu.me/44HGhex Associated Press - https://polyu.me/3UHAC3v ETNet - https://polyu.me/3V3LgTw Macau Business - https://polyu.me/3UJ5CA7 Taiwan Business News - https://polyu.me/3V1UkZ5 Global News - https://polyu.me/4bIX8zF GBA Biz Tech Magazine - https://polyu.me/3V6Aj3O HXCJ - https://polyu.me/4biIXSo Cntechw.com - https://polyu.me/44J3mxq Scienmag - https://polyu.me/4bQn7p4 Science Daily - https://polyu.me/4avRaRS

RILS delegation visit to Shanghai and Tianjin

From 11 to 13 May 2024, a delegation of the Research Institute for Land and Space (RILS), led by Prof. Jian-hua YIN, RILS Management Committee Member and Dr Gavin TOH, Chairman of the Geotechnical Division of The Hong Kong Institution of Engineers (HKIE-GD), had a technical visit to Shanghai and Tianjin. The three-day visit was aimed to facilitate the exploration and development of potential technologies for sustainable land reclamation and development in Hong Kong, through learning from projects involving the utilisation of dredged materials for land reclamation in the cities.   The group visited the Yangshan Deep Water Port and the test site of the National Engineering Research Center of Dredging (NERCD) in Shanghai, as well as the Nangang Industrial Zone and the Dongjiang Port Area in Tianjin. The visit was jointly organised by PolyU and HKIE-GD, and was hosted by the NERCD and China Communications Construction Company Limited’s (CCCC) Marine Construction and Development Co., Ltd.

PolyU studies impacts of urban industrial land expansion on economic growth and carbon dioxide emission

A research by Prof. Qihao WENG, Associate Director of the Research Institute for Land and Space (RILS) and Chair Professor of Geomatics and Artificial Intelligence, and his research team, titled “Unequal impacts of urban industrial land expansion on economic growth and carbon dioxide emissions” was recently published in the journal Communications Earth & Environment.   The team used satellite data and machine learning to map industrial land at 30 m resolution in ten countries with substantial industrial value-added, and analysed the impact of industrial land expansion on economic growth and emissions in 216 subnational regions from 2000 to 2019. They found that industrial land expansion was the leading factor for economic growth and emissions in developing regions, contributing 31% and 55%, respectively. Conversely, developed regions showed a diminished impact (8% and 3%, respectively), with a shift towards other economic growth drivers like education. The findings encourage developing regions to consider the adverse effects of climate change during industrial land expansion and that developed regions prioritise human capital investment over further land expansion.   Read the full article: https://doi.org/10.1038/s43247-024-01375-x

The International Conference on Nature-Based Solutions for Urban Infrastructure was successfully held

The International Conference on Nature-Based Solutions for Urban Infrastructure (NBSUI) was held at Chiang Chen Studio Theatre of The Hong Kong Polytechnic University (PolyU) from 25 to 26 April 2024. The Research Institute for Land and Space (RILS) was one of the co-organisers, and the conference had also received support from the Department of Civil and Environmental Engineering, Research Center for Artificial Intelligence in Geomatics, and Jockey Club STEM Lab of Earth Observations of PolyU. Prof. Yuhong WANG, member of RILS, and Prof. Qihao WENG, Associate Director of RILS, co-chaired the conference successfully. NBSUI 2024 witnessed a remarkable turnout, with over 200 participants from around the world. It provided a valuable platform for research discussions and knowledge sharing on integrating nature into the management of urban infrastructure throughout its lifecycle. Experts, policymakers, researchers, and professionals from diverse fields came together to explore innovative approaches in addressing urban infrastructure challenges using nature-based solutions. The conference commenced with a welcome session featured a few esteemed speakers from PolyU, including Prof. Zuankai WANG, Associate Vice President (Research and Innovation), and Prof. Qingyan CHEN, Director of PAIR, while the opening speech was delivered by Ir Michael FONG, Director of the Civil Engineering and Development Department of the HKSAR Government. The keynote session included presentations from four international distinguished speakers, while the technical session featured 35 scholars and experts who shared their knowledge and experiences across six topics: NBS in Urban Planning and Development, NBS for Urban Resilience, Influences of NBS on the Built Environment, NBS for Ecosystems and Biodiversity, Plants in NBS, and Innovative NBS and Future. In addition, there was a poster session which had showcased 40 posters with state-of-the-art research and technologies. NBSUI 2024 concluded with a site visit and hands-on workshop at the Hong Kong Wetland Park. Led by Prof. Xiaoli DING, Director of RILS, the workshop provided participants with an immersive experience to engage in thematic discussions and practical explorations of nature-based solutions in action. This interactive session not only emphasized the conference's commitment to applied knowledge but also served as a fitting finale to an informative and inspiring event.

DoRILS gives professional opinion on study about China’s major cities is sinking rapidly

Prof. DING Xiaoli, Director of the RILS and Chair Professor of Geomatics of LSGI, was interviewed by the journal Nature and BBC World Service’s programme “Newshour” to comment on a paper which suggests that some 16% of the mapped area of China’s major cities is sinking rapidly, and one in ten residents of China’s coastal cities could be living below sea level within a century. Prof. DING pointed out that while subsidence is not only a problem in China, the study, which was led by a scholar from Peking University, provides an interesting snapshot of the situation in China, and crucially links the issue to the populations affected. According to Prof. DING, the use of groundwater is the main cause of subsidence, and controlling the use of groundwater would be the key for controlling the problem.   Online coverage: Nature - https://polyu.me/4b2VFE5 BBC World Service - https://polyu.me/3xKqaQY (45:05 - 49:05) (registration required) Jandan - https://polyu.me/3U8hueF

PAIR delegation visits Moganshan Geo-Information Laboratory in Deqing

Prof. CHEN Qingyan, Director of the PolyU Academy for Interdisciplinary Research (PAIR), and Prof. DING Xiaoli, Director of the Research Institute for Land and Space (RILS), visited the Moganshan Geo-Information Laboratory in Deqing, Zhejiang on 12–15 April 2024. The PolyU delegation was warmly received by Prof. CHEN Jun, Academician of Chinese Academy of Engineering, Director of Moganshan Geo-Information Laboratory, Senior Fellow of PAIR and International Advisory Committee Member of RILS; Prof. ZHANG Jixian, Executive Director of Moganshan Laboratory; Mr PAN Zhenhua, Member of the Standing Committee of the People’s Government of Deqing County and Director of Department of Human Resources  of the Government; and Mr ZHANG Hongchun, Deputy Director of Moganshan High-Tech Park. The two parties had a fruitful meeting, exploring potential collaborations between PolyU and the Laboratory.   The Moganshan Geo-Information Laboratory, established in November 2023 jointly by the Ministry of Natural Resources of Central Government of China and Zhejiang Province, is dedicated to empowering high-quality sustainable development with spatiotemporal information, and conducts research focusing on four main directions including spatiotemporal perception, spatiotemporal connection, spatiotemporal computing and spatiotemporal intelligence.

Concurrent heatwaves and sea level rises happening more at coastal locations, PolyU study finds

A research conducted by Dr WANG Shuo, Member of the Research Institute for Land and Space (RILS), the Research Institute for Sustainable Urban Development (RISUD) and the Otto Poon Charitable Foundation Smart Cities Research Institute (SCRI), Associate Professor in the Department of Land Surveying and Geo-Informatics (LSGI), and his team has found that the concurrent occurrence of heatwaves and extreme short-term sea level rises at coastal locations significantly increased between 1998 and 2017 when compared to the preceding 20 years. The study also predicted that, under a modelled high emissions scenario, the probability of the occurrence of such events in 2025–2049 may multiply by fivefold. The research findings provide scientific evidence and guidance for improving climate adaptation strategies in response to extreme weather events, which will aid in the development of climate-resilient coastal cities. The study has been published in the journal Communications Earth & Environment. Read the article: https://www.nature.com/articles/s43247-024-01274-1   Online coverage: The United Nations Office for Disaster Risk Reduction (UNDRR): https://www.preventionweb.net/news/study-identifies-increased-threat-coastlines-concurrent-heat-waves-and-sea-level-rises Scientific American: https://www.scientificamerican.com/article/heat-and-floods-are-increasingly-hitting-coastlines-with-a-one-two-punch/ Nature Asia: https://www.natureasia.com/ja-jp/research/highlight/14874 CCTV - https://polyu.me/3JhABOe Xinhua Net - https://polyu.me/3JjRsjK People’s Daily - https://polyu.me/49CbO2i People.com - https://polyu.me/4cQaED4 Jiangnan Evening News - https://polyu.me/3QrfEET Jinhua Daily - https://polyu.me/4aQ7iyN The Paper - https://polyu.me/4aVfflH NetEase - https://polyu.me/3VWKNDu Forbes - https://polyu.me/4aw2tKM The Straits Times - https://polyu.me/3W0TgWf France 24 - https://polyu.me/43VGjiq Eyewitness News - https://polyu.me/3VSO2vK Deccan Herald - https://polyu.me/3vGHlCp The Telegraph Calcutta, India - https://polyu.me/49Afgdy Malay Mail - https://polyu.me/3vHSjaO Daily Excelsior - https://polyu.me/4aWw145 EurekAlert - https://polyu.me/3UgcSV1 China News Service - https://polyu.me/3W2qmoV ifeng.com - https://polyu.me/3UdjgMT