Jin Yeu Tsou

Strategy on applying computational fluid dynamic for building performance evaluation

Predicting and evaluating building performance plays an important role in the training of responsible architects. Building performance includes issues such as: structural stability, acoustic quality, natural lighting, thermal comfort, and ventilation and indoor air quality. These types of analyses are often laborious, non-intuitive, and non-graphical. As a result, these important issues do not arouse the enthusiasm of architecture students or building professionals. The Chinese University of Hong Kong (CUHK) research team proposes to explore and develop a long-term strategy to apply scientific visualization on teaching and research in environmental technology and building performance. This paper presents the development process and results of research projects for applying computational fluid dynamics (CFD) on building performance evaluation. CFD On-line Teaching projects aim is to develop a web-based training course for architecture students to apply CFD simulation on design problem solving. Each lesson not only illustrates basic principles regarding airflow in the building design, it also contains CFD sample files with predefined flow cells for students to test different concepts. GiLin Temple projects aim is to apply CFD simulation on investigating the wind resistance of Tong Dynasty heavy timber structure. Airflow information generated in the project includes the visual representation of the pressure distribution and velocity field on all slices through the temple, and the tracking of particles as they flow around or through a building. The China housing residential airduct study focuses on simulating the indoor airflow regarding the airduct design of China Experimental Urban Housing Scheme. The visual representation of the pressure distribution and velocity field in the airducts provides vital information for helping China Housing Research Center improve the current design.

Performance-based simulation for the planning and design of hyper-dense urban habitation

Abstract The rapid development of the economy and urbanization create great pressure on population of Hong Kong, China and other developing countries. This not only brings great changes on the form and style of the urban sphere, but also, challenges to the natural environment and resources to support urban habitation. Regarding the process of urbanization, the development of the housing industry becomes the focus to resolve the need of materialization for urban living. For this reason, from time to time, technical and economical considerations are always prior to the significance of human settlement environment, humanity, and sustainable development. Considering the deficiency in urban human settlements environment, especially in responsiveness to the natural environment. Information technology (IT) undoubtedly can help to promote and assess the design and planning quality in both environmental and regional microenvironment aspects. A research project—Environmental Responsible Architecture and Urban Design (ERAU)—is established to support urban scale planning, information processing, and computer-aided performance evaluation on both micro- and macro-building design and planning efficiency.

A Visual Landscape Assessment Approach for High-density Urban Development

The rapid developments of economy and urbanization bring great pressure to natural environment and resources, which contribute big challenge to sustainable urban development in high-density urban areas like Hong Kong, China and many other Eastern Asia cities. In these areas, protecting natural landscape resources and enhancing visibility to urban spaces and residential zones has become significant in improving the livability of human settlement. This paper presents a new approach in assessing the visual quality in high-density urban environment. The principal methodology is to quantitatively integrate human visual perception parameters with the visible landscape resources’ characteristics. GIS is employed as the database and technical platform. A residential development in Hong Kong was used as a case study. The approach provides decision making support to urban planning, site layout design, and estate management during the early stage of the schematic design/planning process.

Monitoring of chlorophyll-a and sea surface silicate concentrations in the south part of Cheju island in the East China sea using MODIS data

Abstract Continually supplied with nutrients, phytoplankton maintains high productivity under ideal illumination and temperature conditions. Data in the south part of Cheju Island in the East China Sea (ECS), which has experienced a spring bloom since the 2000s, were acquired during a research cruise in the spring of 2007. Compared with in-situ measurements, MODIS chlorophyll-a measurements showed high stability in this area. Excluding some invalid stations data, the relationships between nutrients and chlorophyll-a concentrations in the study area were examined and compared with the results in 2015. A high positive correlation between silicate and chlorophyll-a concentration was identified, and a regression relationship was proposed. MODIS chlorophyll-a measurements and sea surface temperature were utilized to determine surface silicate distribution. The silicate concentration retrieved from MODIS exhibited good agreement with in-situ measurements with R2 of 0.803, root mean square error (RMSE) of 0.326 μmol/L (8.23%), and mean absolute error (MAE) of 0.925 μmol/L (23.38%). The study provides a new solution to identify nutrient distributions using satellite data such as MODIS for water bodies, but the method still needs to be refined to determine the relationship of chlorophyll-a and nutrients during other seasons to monitor water quality in this and other areas.

Evaluating urban land carrying capacity based on the ecological sensitivity analysis : a case study in Hangzhou, China

Abstract: In this study, we present the evaluation of urban land carrying capacity (ULCC) based on an ecological sensitivity analysis. Remote sensing data and geographic information system (GIS) technology are employed to analyze topographic conditions, land-use types, the intensity of urban development, and ecological environmental sensitivity to create reasonable evaluation indicators to analyze urban land carrying capacity based on ecological sensitivity in the rapidly developing megacity of Hangzhou, China. In the study, ecological sensitivity is grouped into four levels: non-sensitive, lightly sensitive, moderately sensitive, and highly sensitive. The results show that the ecological sensitivity increases progressively from the center to the periphery. The results also show that ULCC is determined by ecologically sensitive levels and that the ULCC is categorized into four levels. Even though it is limited by the four levels, the ULCC still has a large margin if compared with the current population numbers. The study suggests that the urban ecological environment will continue to sustain the current population size in the short-term future. However, it is necessary to focus on the protection of distinctive natural landscapes so that decision makers can adjust measures for ecological conditions to carry out the sustainable development of populations, natural resources, and the environment in megacities like Hangzhou, China.

Assessing Texture Features to Classify Coastal Wetland Vegetation from High Spatial Resolution Imagery Using Completed Local Binary Patterns (CLBP)

Coastal wetland vegetation is a vital component that plays an important role in environmental protection and the maintenance of the ecological balance. As such, the efficient classification of coastal wetland vegetation types is key to the preservation of wetlands. Based on its detailed spatial information, high spatial resolution imagery constitutes an important tool for extracting suitable texture features for improving the accuracy of classification. In this paper, a texture feature, Completed Local Binary Patterns (CLBP), which is highly suitable for face recognition, is presented and applied to vegetation classification using high spatial resolution Pleiades satellite imagery in the central zone of Yancheng National Natural Reservation (YNNR) in Jiangsu, China. To demonstrate the potential of CLBP texture features, Grey Level Co-occurrence Matrix (GLCM) texture features were used to compare the classification. Using spectral data alone and spectral data combined with texture features, the image was classified using a Support Vector Machine (SVM) based on vegetation types. The results show that CLBP and GLCM texture features yielded an accuracy 6.50% higher than that gained when using only spectral information for vegetation classification. However, CLBP showed greater improvement in terms of classification accuracy than GLCM for Spartina alterniflora. Furthermore, for the CLBP features, CLBP_magnitude (CLBP_m) was more effective than CLBP_sign (CLBP_s), CLBP_center (CLBP_c), and CLBP_s/m or CLBP_s/m/c. These findings suggest that the CLBP approach offers potential for vegetation classification in high spatial resolution images.

Evaluation of the Influence of Aquatic Plants and Lake Bottom on the Remote-Sensing Reflectance of Optically Shallow Waters

Abstract Aquatic plants and lake bottoms in optically shallow waters (OSWs) wield great influence on reflectance spectra, resulting in the inapplicability of most existing bio-optical models for water colour remote sensing in lakes. Based on radiative transfer theory and measured spectra from a campaign for Lake Taihu in October 2008, absorption and backscattering coefficients were used to simulate the remote-sensing reflectance, which are considered to be reliable if matched to their measured counterparts. Several cases of measured spectra at different depths, Secchi disk depth transparency, and aquatic plant height and coverage were analyzed thoroughly for spectral properties. The contribution of aquatic plants was evaluated and compared with the measured and simulated remote-sensing reflectance values. This is helpful for removing the influence of aquatic plants and lake bottoms from the spectra and for constructing an improved chlorophyll a retrieval model for OSWs, such as that for Lake Taihu, China.

Monitoring of the 2008 Chaitén Eruption Cloud Using MODIS Data and its Impacts

This chapter presents the monitoring of the 2008 Chaitén eruption cloud using Moderate Resolution Imaging Spectroradiometer (MODIS) data and its impacts. The 8-day MODIS data from 3 to 10 May 2008 were used to track the movement and dispersion of the eruption cloud of the Chaitén volcano in Chile following the eruption on 2 May 2008. For detecting volcanic particulates, the procedure is adopted based on the brightness temperature difference (BTD) algorithm, by which the thermal infrared channels were centered on 11–12 μm of multispectral satellite sensors. The BTD is generally negative for volcanic ash but positive for ice and water vapor. The eruption cloud was found to drift northeastward, eastward, and southeastward crossing the central and northern part of Argentina and over the Atlantic Ocean. The timing of heavy rainfall in South Africa during May–June, in central Australia during June 2008 and in Hong Kong during June (the wettest since record began in 1884), was considered to have been connected to the dispersion of the particulates from this Chaitén eruption to further impact downstream.

Applying RS and GIS to Study the Impacts of Urban Regeneration on Thermal Environment in Built-Up Areas: A Case Study of Kowloon, Hong Kong

Land use/Land cover (LULC) change is one of the key reasons for the Urban Heat Island (UHI) dynamic. Previous studies focused on the relationship of urban sprawl and emergence of UHI; but, less attention was paid to how urban regeneration progress influences the thermal environment in built-up regions. In this paper, a comparative study of Kowloon, Kuwn Tong and Kwai Tsing was conducted on the LULC and Urban Heat Island Intensity (UHII) in 2000 and 2010. The study investigated the effect of urban regeneration progress on thermal behavior of the built-up environment. Landsat 7 ETM+ data was used to retrieve the UHII of the two periods in the study area. A spatial quantitative analysis was made through the integration of Remote Sensing (RS) and the Geographical Information System (GIS) analysis tool. The results presented an evident enhancement of UHI in Kowloon East within the 10 years of urban development. The study results provides reference to optimize the master plan of Kowloon East and contribute to the innovative thinking in applying scientific methods to support the decision-making in urban regeneration schemes to avoid environmental issues that the urban regeneration process may bring about.

An Innovative Communication Channel for Local Residents on a Proposed Public Utility Service Building

Communication with the public is one of the vital functions of architectural design firms today, especially those that design public facilities. Architects always visualize their design concepts and present the idea to clients by various means. The challenge is to bring the three-dimensional reality of projects, existing site conditions, local context and the design teams experience into a visual format that can be communicated to the public, and to get feedback from them before the facility gets built. As demand for electricity in Hong Kong continues to grow, CLP Power (one of the local power supply companies) has to continue to expand its distribution network, including the construction of new substations. As with any large property owner, the corporates image is influenced by the design, construction and maintenance of its facility — especially in the highly congested urban context like Hong Kong. Collaborating with CLP Power engineers, the Department of Architecture, the Chinese University of Hong Kong (CUHK) applied computer visualization techniques to carry out the visual impact assessment on the proposed substation at the Lee On estate. CUHK research team explored various computing technologies on improving the effectiveness of the communication among civil engineers, electrical engineers, architects, and public community. The main objective is to have community involved in the design development process of the public facility planning/design in order to improve the urban living context.