Perry Pei-Ju Yang

Viewsphere: A GIS-Based 3D Visibility Analysis for Urban Design Evaluation

Previously, GIS-based visibility analysis has been conducted mainly in two dimensions, based on the concept of an isovist in the built environment or the concept of a viewshed in terrain and landscape analysis. The Viewsphere, a GIS approach towards 3D visibility analysis is proposed for measuring visible urban space quantitatively in a way that is different from its predecessors, the isovist and the viewshed. A test case of Singapores urban space was conducted by evaluating the visibility of three alternative urban design scenarios and their potential impacts on the visual quality of open space. Both directional and nondirectional approaches were applied to the mapping of visibility based on the 2D and 3D indices. The proposition that 3D visibility indices are more effective than 2D indices was verified. The findings show that the 3D indices are sensitive to the changes of z-dimension.

Urban Data and Building Energy Modeling: A GIS-Based Urban Building Energy Modeling System Using the Urban-EPC Engine

There is a lack of building energy modeling in current planning support systems (PSS) while building energy efficiency is getting greater attention. This is due to the current limitations of energy modeling at the urban scale and the inconsistency between the available urban data and that required for modeling. The chapter seeks to fill this gap by developing a GIS-based urban building energy modeling system, using the Urban-EPC simulation engine, a modified Energy Performance Calculator engine. This modeling system is compatible with other planning tools, enhanced by the combination of physical and statistical modeling, and adjustable in its resolution, speed and accuracy. Through processing the Data Preparation, Pre-Simulation, Main Simulation and Visualization and Analysis models in this energy modeling system, the urban data related to the basic building information, mutual shading, microclimate and occupant behavior are collected, modified, and synthesized in the GIS platform and then used as the input of the Urban-EPC engine to get energy use of every building in a city, which could be further visualized and analyzed. The method is applied in Manhattan to show its potential as an important component in PSS to inform urban energy policy making.

GIS-based Planning Support System for Waste Stream and Algal Cultivation in Residential Construction

Technologies of alternative energy generation for residential communities using algal material, involving the construction of bioreactors with solar cells, storage of raw materials, construction of central plants for conversion of bio-fuels, and delivery systems to users, will have different design impacts at different scales. This paper intends to define basic design and planning parameters for residential construction in accordance with the scientific knowledge and technical criteria available regarding the potential for algal biofuel production and sustainable urban living. This paper suggests a framework of GIS-based planning support system for informing processes of data representation, performance assessment and design for the coupled algae cultivation and urban systems.

GIS-BIM Framework for Integrating Urban Systems, Waste Stream and Algal Cultivation in Residential Construction

Among alternative energy sources for residential buildings, algae technology has emerged as a promising option due to its closed-loop configuration and the ability to produce biofuel energy while reducing waste stream flow and capturing carbon. Furthermore, this technology has the potential of integrating resource and waste management, and can be complemented with other alternatives, such as photovoltaic, wind or fuel cells. This paper provides a framework for integrating information from geographic information systems, building information models, construction schedules, construction cost estimates, and constructability reviews. The integration is aimed at designing an algae-powered residential building environment at the level of urban neighbourhood, in which the algae technology is taken as a design intervention to promote energy performance and carbon reduction within the urban system. This framework couples the design intervention with impact simulations influenced by geographic contexts, construction considerations, and digital building technology. By extending the system boundary from a closed algae cultivation system to an open neighbourhood-scale urban environment, urban renewable resources such as energy, water, material and carbon flows are connected to the algae cultivation process. The framework would further advance the possibilities for sharing information among planners, architects, engineers and construction managers for innovative closed-loop sustainable energy systems in residential construction. This approach will address challenges such as cost, governmental incentives, regulatory barriers, or need of research and development that could overcome limitations for automating predesign, design, construction and facility management processes.

A GIS-Based Performance Metrics for Designing a Low Energy Urban Agriculture System

This chapter explores a GIS-based performance metric for designing a low energy agriculture system in the City of Atlanta. A framework of a planning support system (PSS) is proposed, which contains dimensions of representation, performance and scenario planning. The specific PSS demonstrated how a performance-oriented urban design decision model reorganizes fragmented information and turns them into useful representational layers, analyses of performance measures, and scenario planning for making design decisions.

Questioning urban sustainability: social sufficiency, ecological efficiency and ecosystems compatibility

In 1987, the Brundtland Report was published to define the meaning of sustainable development as an approach to development that meets the present needs without compromising the ability of future generations to meet their own needs (World Commission on Environment and Development 1987). Since the early 1990s, sustainable development, particularly the concept of urban sustainability, or ideas about sustainable cities and regional planning have emerged. The original concept of sustainable development was regarded as too broad to be implemented – something you try very hard to achieve but never will. The definition in the Brundtland Report did not indicate how the principle of generational justice could be mapped into decisions in everyday urban contexts. The challenges to urban design and planning professionals would be how to translate the objectives of sustainability into actual urban contexts. What has been done, what made the change, and what constitutes the contemporary debates over the sustainability discourse in the past decades? We search for an operational approach to metrics of urban sustainability that is measurable and can be used to bridge the knowledge and tools of architecture and city planning in general. To examine the propositions, I have highlighted two contentious concepts as follows:

Urban Form and Energy Resilient Strategies: A Case Study of the Manhattan Grid

The Manhattan grid is known as a testing ground of high-density urban development from the 19th century onward. Its urban form model and regulatory zoning mechanisms provide lessons for global cities in shaping their urban skylines. This chapter describes the physical form and processes that have established and characterize Manhattan’s grid, focusing on the grid as a generator and framework for growth. A performance-based urban energy model is used to examine the potential for energy self-sufficiency within the current urban form structure of the Manhattan grid. To make the city more energy resilient, a transformative approach is proposed that centers on the implementation of a performance-based model of urban design, which enhances urban resiliency at the neighborhood level. The concept of panarchy is applied to address complex systems problems such as energy resiliency in cities. To design an energy resilient urban system, it is important to define a community-level action and a medium-scale framework, which allow effective systems integration and coordination among stakeholders. The framework of urban design accommodates finer-scale, bottom-up eco-initiatives, which enable agile responses to unpredictable events, such as climate-induced disasters and environmental changes.

Energy Resilient Urban Planning

Recent discussions on Geodesign reoriented Geographic Information System (GIS) and Planning Support System (PSS) professionals to be more design-focused. The paper introduces a GIS-based energy performance and carbon emissions assessment for urban design that is a forward-looking modeling approach to address the issue of how the scientific-based analysis articulates design. Seven global cities and their central urban districts are chosen for mapping the urban form structure, energy performance, carbon footprint and solar availability of the built environment. The relationship between urban form and its energy and carbon efficiency is explored through benchmarking their performance. A sample urban block modeling is conducted and an interventional design approach is taken for showing how new urban form and internal organization of cities matter and affect the energy and carbon efficiency. Urban design is seen as a tool to synthesize complex factors for projecting a forward-looking future urban system.

Enduring Innocence: Global Architecture and Its Political Masquerades ‐ Edited by Keller Easterling

Keller Easterling’s Organization Space (MIT Press, 1999) proposed the importance of network thinking and organizational logic behind the production of architectural space in order to investigate ‘‘the real power of many urban organizations that lies within the relationships among multiple distributed sites that are both collectively and individually adjustable’’ (p. 2). In Enduring Innocence: Global Architecture and Its Political Masquerades, she has fully realized this argument, extending the geographic boundary of architectural discourse to the new frontier of unfamiliar areas outside the United States. Here, she successfully shows how organizational logics are providing generic specification for assembling spaces for North Korean tourism, Spanish high-tech agricultural landscapes, East Asian container ports, Indian IT (information technology) campuses, golf courses, retail franchises, pirates, and terrorism around the world. The world landscapes described in the book appear more and more fragmented, with many isolated small worlds or segregated ‘‘scapes,’’ including golf worlds, mediascapes, ethnoscapes, technoscapes, and global port images. These different kinds of urbanism—such as agricultural urbanism, microwave urbanism, and broadcast urbanism—formulate a new global urbanism that extends the worldview through a new perspective.There is ‘‘no one world,’’ only many segregated worlds (p. 4). The design of the book represents the fragmented and segregated picture of these world landscapes. There are six case studies and three specific commentaries. The six stories ‘‘DPRK,’’ ‘‘El Ejido,’’ ‘‘Franchise,’’ ‘‘Park,’’ ‘‘Shining,’’ and ‘‘Subtraction’’ are paired with three distinctive terminologies, place names (‘‘DPRK’’ and ‘‘El Ejido’’), spatial typology (‘‘Franchise’’ and ‘‘Park’’), and analogy (‘‘Shining’’ and ‘‘Subtraction’’). The three commentaries ‘‘Seas,’’ ‘‘Error,’’ and ‘‘Pirate’’ provide a similar sense of detachment, although the essays have implicit links to the conceptualization of the stories. The writing strategy of defamiliarizing the six unfamiliar environments