Marcel Ignatius

National University of Singapore | NUS · Department of the Built Environment

This research applied clustering to unsupervised learning of meteorological data and evaluated the impact of urban morphology on temperature in different weather. Air Temperature Learning Algorithms (ATLAS) was developed for the cluster analysis of urban meteorological data and regression analysis of urban morphology and outdoor air temperature. Th...

This paper introduces a physically-based model to simulate interactions between a building and its outdoor conditions at the urban microscale. In the model, the building is simulated with EnergyPlus while its outdoor conditions are assessed from OpenFOAM. Furthermore, the model simulates the street pavement and surrounding buildings based on the lu...

In year 2003, United Nations estimated that by year 2030, up to 5 billion people will live in urban areas which will be 61% of the world's population. Urbanization brings major modification on natural landscape; buildings are erected, soil has been transformed into roads and pavement, greenery has been vastly reduced, etc. The deterioration of the...

Street-view-based techniques for assessing the sky view factor (SVF) and solar irradiance under trees are gaining attention as tools for evaluating trees as nature-based solutions to mitigate urban heat risks. Although these metrics significantly depend on the morphology of trees and resulting canopy transmittance, an existing approach, termed the...

High-resolution microclimate data is essential for capturing spatio-temporal heterogeneity of urban climate and heat health management. However, previous studies have relied on dense measurements that require significant costs for equipment, or on physical simulations demanding intensive computational loads. As a potential alternative to these meth...

This research examines the interplay of outdoor thermal comfort, walkability, and three-dimensional geospatial landscape within cities. Employing advanced data collection methods, including smart wearables and street view imagery (SVI), we conduct a comprehensive exploration of integrating heterogeneous sensor data and computer vision in an urban d...

This paper describes a dataset collected by infrared thermography, a non-contact, non-intrusive technique to acquire data and analyze the built environment in various aspects. While most studies focus on the city and building scales, an observatory installed on a rooftop provides high temporal and spatial resolution observations with dynamic intera...

Ensuring effective forecasting of buildings' energy consumption is crucial in establishing a greater understanding and improvement of buildings' energy efficiency. In Singapore, domestic electricity usage in public residential buildings takes up a significant portion of the country's annual energy consumption. Having effective forecasting approache...

The paper describes a dataset that was collected by infrared thermography, which is a non-contact, non-intrusive technique to collect data and analyze the built environment in various aspects. While most studies focus on the city and building scales, the rooftop observatory provides high temporal and spatial resolution observations with dynamic int...

This research evaluated the spatiotemporal dimension of the thermal environment of urban microclimate system in Singapore through a case study. To provide a holistic assessment of air temperature due to urban morphology, for the spatial dimension, correlations between different urban morphology variables and estate-level air temperature were examin...

Urban heat island (UHI) is considered a serious environmental issue in highly urbanized cities such as Singapore. To better quantify the UHI intensity, the local climate zones (LCZ) classification scheme was adopted to characterize land covers, and describe and compare their thermal performance. There are three commonly used LCZ classification appr...

Limited studies have been carried out to assess glare from surrounding buildings with in-depth analysis. This study evaluated how the façade of a building could impact the glare condition of its surrounding building by carrying out a parametric study involving 21,120 scenarios. The parametric study considered five parameters: reflectance of the aff...

In environments with similar physical parameters, thermal comfort and sensation feelings may differ indoors and outdoors. How indoor and outdoor thermal perception differ from each other remains unclear. This study compared and discussed 29,536 field survey data, including 19,191 sets of indoor data, and 10,345 sets of outdoor data, covering five K...

In a highly populated country like Singapore, a significant percentage of our gross annual electricity consumption stems from our domestic electricity usage in our residential houses. Analyzing and understanding factors that could influence such patterns is thus essential in order to derive effective measures to reduce usage. In this research, 16 i...

The urban heat island (UHI) is one of the most critical issues for dense urban environments, as high outdoor temperatures and poor wind flow in high-density built-up areas can have negative impacts on the thermal comfort and health of city dwellers by trapping air pollutants and increasing energy demand for artificial cooling. The Intergovernmental...

The study examines the impacts of glare caused by highly reflective building façade material on the thermal and visual performance of surrounding development under tropical climate context. A 9-story commercial building with a curved stainless-steel façade was investigated, as it produces discomfort glare to the surrounding buildings due to direct...

The rising air temperature caused by Urban Heat Island (UHI) effect has become a problem for Singapore, it not only affects the thermal comfort of outdoor microclimate environment, but also increases the cooling energy consumption of buildings. As part of a multiscale and multi-physics urban microclimate model, weather stations were installed at 15...

Urban heat island (UHI) can be described as characteristics of warmth for both the atmospheres and surfaces in cities compared to rural surroundings. The attention on UHI has helped to advance the development of urban cooling strategies in Singapore. However, these strategies are often implemented at different levels with different mechanisms, and...

This study investigates the impacts of highly reflective building façade material on the thermal and visual performance of surrounding building in the tropical climate. One 9-story commercial building which designed with curved stainless-steel façade was studied. Field measurement was conducted in one surrounding building which is affected by the a...

The study examines the impacts of glare caused by highly reflective building façade material on the thermal and visual performance of surrounding development under tropical climate context. A 9-story commercial building with a curved stainless-steel façade was investigated, as it produces discomfort glare to the surrounding buildings when its metal...

With the rapid growth and use of modern architecture practices for high-rise buildings, highly reflective materials have been adopted extensively for aesthetical reasons. However, outdoor glare from highly reflective facades might cause thermal and visual problems towards the occupants of neighbouring buildings and outdoor dwellers, particularly pe...

It is important to alleviate the "heat island effect" in urban areas, especially tropical cities. Microclimate is normally affected by the urban morphology parameters. The objective of this work is to investigate the correlation between air temperature variations and urban morphology parameters in tropical cities. Field measurement was carried out...

Air temperature in built environment is a critical indicator of both outdoor thermal comfort and space cooling or heating loads in buildings. The objective of this work is to investigate the correlation between air temperature variations in built environment and urban morphology in northern China. Field measurement was firstly carried out to record...

This work is an experimental study focusing on the impact of urban morphology on the urban heat island (UHI) intensity, microclimate conditions and thermal comfort in a newly-developed urban area in Tianjin city, China. According to the Köppen–Geiger climate classification system, the studied area is classified as hot summer continental climate, ch...

Due to increasing urbanization and heat island issues, current cities need to sensibly plan their future developments to preserve the quality of their urban environment. An urban climatic map (UCmap) method can be utilized for this purpose to examine the effectiveness of various urban environmental solutions in improving environmental conditions, p...

Calibration of a building energy model is a critical step preceding evaluation of energy savings we can make by applying retrofitting strategies. Simplified building energy models are often preferred over detailed ones to speed up the process of calibration. Nevertheless, discrepancy between measured and estimated indoor energy consumption can pote...

For the past twenty years, the haze has been one of the main concerns of Singaporean authorities. Nowadays, a growing interest can be observed within the scientific community to better understand the consequences of this phenomenon on population health. The Pollutant Standards Index (PSI) is a metric used to evaluate the intensity of the haze. The...

Urban climatic map (UCMap) study was introduced 40 years ago, and since then the interest on this field has been growing, where there are more than 15 countries which have been developing and implementing UCMap to their relevant design guidelines, environmental studies, or mitigating climate change issues in urban areas. For example, researchers in...

Poster presentation for Croucher Advanced Study Institute 2015, Chinese University of Hong Kong (7-11 December 2015).

This article discusses the definition of urban heat island and its impact to Singapore. Furthermore, it also explores the contributing factors and mitigation solutions. The article is based on long term research conducted by Prof Wong Nyuk Hien's research group, ranging from urban climatic mapping, urban texture analysis, urban climatic modeling, l...

The world has experienced unprecedented urban growth in the last century. For the first time in history, more than half of the world population were urban dwellers in 2008. United Nations estimated that by year 2030, up to 5 billion people will live in urban areas, or 61% of the world's population. Consequently, cities are growing towards megaciti...

Global urbanization has caused significant increase of urban dwellers. In year 2003, United Nations estimated that by year 2030, up to 5 billion people will live in urban areas which will be 61% of the world's population. Urbanization brings major modification on natural landscape; buildings are erected, soil has been transformed into roads and pav...

With increasing urbanization today, the negative impact it has on its surroundings is prevalent in many cities and urban areas. Coupled with the need to create and develop sustainable urban developments, it is essential to understand how much the environment as well as its surrounding morphology affects the built environment. Greater emphasis shoul...

In urban areas, natural land soil has been replaced by asphalt roads and concrete buildings, which absorb and retain more heat during the day, creating the Urban Heat Island (UHI) phenomenon. Current studies show that UHI impact mitigation strategies are to increase the open spaces to allow urban ventilation and plant green cover. To complement thi...

Local climate condition and urban morphology affect air temperature generated within urban canopy layer which related to urban heat island (UHI) intensity and later impacts on outdoor thermal comfort and urban energy usage. Climatic responsive urban planning by careful consideration on urban morphology parameters of urban corridor width, building h...

This paper aims to evaluate the possibilities of introducing urban greenery to improve the thermal climate of the commercial districts of the city of Dhaka, Bangladesh, a tropical region characterized by high density of population and built up areas. Dhaka had a legacy of being a green city in the past. However, due to rapid and unplanned urbanizat...