Syed Monjur Murshed

This paper investigates how natural resource conditions impact the physical development of cities and how, once built, the urban spatial structure leads to different patterns of resource use. The point of departure for this research is the common “resource urbanisms” assumption that cities are directly affected by the availability and costs of natural resources, and that in turn, different urbanisms result in substantial differences in resource use and consequent impact on the environment. Considering extreme and divergent, higher-income urban models of Kuwait, Abu Dhabi, Hong Kong and Singapore, the paper focusses on two resources, land and energy, and the case of building cooling and transport energy demand. The research uses a mixed methods approach which includes qualitative methods such as expert interviews, analysis of planning documents and historic planning decisions, alongside quantitative methods such as remote sensing, GIS and data analysis and energy modelling. The paper suggests that land availability is a major driver of urban form while energy prices may play a secondary role. It also finds that urban form-induced energy efficiencies for transport and cooling energy diverge in the four cities by a factor of five and two, respectively.

Visualization of underground infrastructure in an interactive 3D immersive environment is extremely important for efficient management of city’s infrastructure. This paper describes different geometric modelling approaches to illustrate appropriate visualization of such data. A multimodal prototype has been developed by exploiting different algorithms to render these invisible underground objects as part of an urban model. This prototype has been integrated in an immersive geographic information system (GIS), named MultiVis, for handheld iOS and Android devices. As a part of the study, three distinct strategies have been tested; the first is based on the use of transparencies to convey a sense of depth, the second relies on an image-space superposition of “ditches” on top of the rendered frame and the third is a world-space deformation of the elevation model that exposes the underground elements. Furthermore, a comparative user experience analysis of different techniques aimed to the geometrically accurate visualisation of utility networks and other underground facilities are performed and evaluated. It includes a set of user evaluations for different parameters of these techniques, which gives us an insight on how the proposed methods affect the experience and usability for technical and non-technical users.

Sustainable development of cities and the overall efficiency of urban infrastructure have emerged as central issues in policy consideration. Consequently, investigating the influence of urban physical form on resource use is critical. This paper investigates energy use due to vertical mobility in the context of Asia’s diverging cities. Micro mobility of citizens’ movement in the vertical direction has a distinct impact on the total energy consumption of a city or urban block. The objective of this research is to analyse the impact of different urban morphologies on vertical mobility—from buildings to urban blocks. A methodology is proposed to calculate energy consumption of lifts, based on a detailed review of literature, codes of practice, the International Organisation for Standardisation (ISO)/DIS 25745-1 standard and 3D city models. Furthermore, a tool is developed and applied in 20 typical urban blocks in four cities: Kuwait, Abu Dhabi, Hong Kong and Singapore. The average annual specific energy consumption of lifts varies significantly across the samples. A comparative analysis of all the morphologies across these cities help to understand the impact of building forms, usage, and a number of further parameters on the energy consumption for vertical mobility.

New planning tools are required to depict the complete building stock in a city and investigate detailed measures on reaching local and global targets to improve energy efficiency and reduce greenhouse gas emissions. To pursue this objective, ISO (the International Organization for Standardization) 13790:2008 monthly heating and cooling energy calculation method is implemented using geometric information from 3D city models (e.g., CityGML format) in an open source software architecture. A model is developed and applied in several urban districts with different number of 3D buildings in various cities. The model is validated with the simulation software TRNSYS. We also perform a sensitivity analysis to quantify the impact of climate change and other physical and behavioral factors on modelling results. The proposed approach can help to perform city or district-wide analysis of the building energy needs and prepare different renovation plans to support decision-making, which finally will enhance the livability of a city and the quality of life of the citizens.

Contemporary development of computer hardware and software, WebGIS and geo-web services as well as the availability of semantic 3D city models, facilitate flexible and dynamic implementation of web applications. The aim of this paper is to introduce 4D CANVAS, a web-based application for dynamic visualization of 3D geospatial data for improved decision making in smart city applications. It is based on the Cesium Virtual Globe, an open-source JavaScript library developed with HTML5 and WebGL. At first, different data formats such as JSON, GeoJSON, Cesium Markup Language (CZML) and 3D Tiles are evaluated for their suitability in 4D visualization applications. Then, an interactive Graphical User Interface (GUI) is built observing the principle of cartographic standards to view, manage, understand and explore different simulation outputs at multiple spatial (3D surface of buildings) and temporal (hourly, daily, monthly) resolutions. In this regard, multiple tools such as aggregation, data classification, etc. are developed utilizing JavaScript libraries. As a proof of concept, two energy simulations and their outputs of different spatial and temporal resolutions are demonstrated in five Asian and European cities. Finally, the 4D CANVAS is deployed both in desktop and multi-touch screens. The proposed application allows easy integration of any other geospatial simulation results, thereby helps the users from different sectors to explore them interactively in 4D.

Keywords: 3D city model, urban planning, heat energy demand, energy systems, Agent-Based Modelling Today's needs to reduce the environmental impact of energy use impose dramatic changes for energy infrastructure and existing demand patterns (e.g. buildings) corresponding to their specific context. In addition, future energy systems are expected to integrate a considerable share of fluctuating power sources and equally a high share of distributed generation of electricity. Energy system models capable of describing such future systems and allowing the simulation of the impact of these developments thus require a spatial representation in order to reflect the local context and the boundary conditions. This paper describes two recent research approaches developed at EIFER in the fields of (a) geo-localised simulation of heat energy demand in cities based on 3D morphological data and (b) spatially explicit Agent-Based Models (ABM) for the simulation of smart grids. 3D city models were used to assess solar potential and heat energy demand of residential buildings which enable cities to target the building refurbishment potentials. Distributed energy systems require innovative modelling techniques where individual components are represented and can interact. With this approach, several smart grid demonstrators were simulated, where heterogeneous models are spatially represented. Coupling 3D geodata with energy system ABMs holds different advantages for both approaches. On one hand, energy system models can be enhanced with high resolution data from 3D city models and their semantic relations. Furthermore, they allow for spatial analysis and visualisation of the results, with emphasis on spatially and structurally correlations among the different layers (e.g. infrastructure, buildings, administrative zones) to provide an integrated approach. On the other hand, 3D models can benefit from more detailed system description of energy infrastructure, representing dynamic phenomena and high resolution models for energy use at component level. The proposed modelling strategies conceptually and practically integrate urban spatial and energy planning approaches. The combined modelling approach that will be developed based on the described sectorial models holds the potential to represent hybrid energy systems coupling distributed generation of electricity with thermal conversion systems.