A selection of current ESD research projects is listed below.
Collaborative Urban Logistics Study (IMDA)
Lynette Cheah and Costas Courcoubetis
This project evaluates potential urban freight consolidation or collaborative urban logistics solutions for deliveries to retail malls. In particular, there are two concepts we would like to investigate: (1) in-mall goods distribution systems, and (2) off-site freight consolidation centres.
Uncertainty in Life Cycle Assessments (LCA) (IDC)
Lynette Cheah, Stephen Ross and Karen Willcox (MIT)
We examine ways to characterize, propagate and communicate uncertainty and variation in current LCA methodology. A data-driven approach is used to construct stochastic models of two LCA cases: automobiles, and building cooling systems.
Urban Freight Transport Data Collection and Modeling (NRF/MND)
Lynette Cheah, Costas Courcoubetis and Ngai-Man Cheung (ISTD)
Optimizing urban freight transport is a complex socio-technical problem that concerns urban planning, transportation system planning, and infrastructure planning. In this project, we deploy innovative data collection methods and develop models that assesses the traffic and environmental impact of goods movement in a city. In collaboration with the Singapore-MIT Alliance for Research and Technology Future of Urban Mobility (SMART FM) group.
Economic Models of Cyber-Physical System Security (NRF ASPIRE)
Costas Courcoubetis and Duan Lingjie
We use languages and tools from network science and economics to model and analyze attack costs of cyber-physical systems. Specifically, we look at applications to power and water systems for developing economic models of security. Based on the cost and economic models, we propose game theoretical approaches and incentive mechanisms for various stakeholders to invest and secure the large-scale power and water systems. This project finally provides practical guidances for designing and securing actual cyber-physical systems.
Green Wireless Networks with Energy and Communication Cooperation (SUTD-ZJU Collaboration Project) (SUTD-ZJU Joint Collaboration Grant)
Energy Cost of cellular networks is ever-increasing to match the surge of wireless data traffic, and the saving of this cost is important to reduce the operational expenditure (OPEX) of wireless operators in future. The recent advancements of renewal energy integration and two-way energy flow in smart grid provide potential new solutions to save the cost. However, they also impose challenges, especially on how to use the stochastically and spatially distributed renewable energy harvested at cellular base stations (BSs) to reliably supply time- and space-varying wireless traffic over cellular networks. To overcome these challenges, there are 3 approaches, namely, energy cooperation, communication cooperation, and joint energy and communication operation, in which different BSs bidirectionally trade or share energy via the aggregator in smart grid, and/or share wireless resources and shift loads with each other to reduce the total energy cost.
Proactive Information Surveillance in Wireless Networks (T-Lab Project) (Temasek Laboratories, 2016)
This project proposes a paradigm shift in wireless security and will develop a new information surveillance for a government agency to monitor and/or intervene suspicious wireless communications. It will develop joint passive eavesdropping and active jamming to maximize surveillance throughput in a proactive way. The project is highly inter-disciplinary by advancing communication theory and applying game theory.
Theory and Methods for User-Provided Wireless Markets over Complex Networks (MOE AcRF Tier 2 Project)
Today users’ data demand is increasing exponentially and their monthly payments are ever-increasing. Given the limited core network capacity, how to secure the service quality and reduce users payments is the key design objective for 5G system. The project aims to promote a new theoretical research direction of 5G sharing economy for emerging mobile data markets, by crowdsourcing mobile devices and resources at the network edge to serve users efficiently.
Development of a Methodology for Assessing the Impact of Flooding Events in Urban Areas (Economic Development Board Industrial PostGraduate Programme (with Veolia))
As a result of climate change and urbanization, more frequent flooding, diffuse pollution, and combined or separate sewer overflows are impacting on infrastructures, private or public entities, and on the ecological status of urban water systems. Which flood management strategies will be the most appropriate/effective under a given local climate scenarios? Answering to such question is crucial for future flood protection planning, and the implementation of cost-beneficial, and effective flood mitigation measures in dense populated areas susceptible to flooding. Based on an optimisation methodology developed and deployed by Veolia, we aim to develop a decision support platform assessing on flooding exposures of a city and its critical assets, to propose territory arrangements to mitigate the impact of flooding events at lowest cost and best efficiency, and flooding management strategies from predefined scenarii based on available historical records.
Engineered Tools to Control Soil Erosion in Large Watersheds (SUTD-ZJU Research Collaboration Grant)
Because of its negative effect on cropland productivity and drainage efficiency in urban areas, soil erosion is deemed one of the severest environmental problems around the world. Among various erosion control measures, check-dams – i.e., small dams constructed across swales, waterways and drainage ditches are the most widely implemented, since they effectively limit erosion by reducing water flow velocity. By the end of 2005 in Chinese Loess Plateau alone, more than 120,000 check-dams have been built – a number that will be doubled by 2020, holding 3,340 km2 of dam-farmlands and 2.1×1010 m3 of sediments. Although their importance has been well recognized, the potential hydrologic-response changes and geomorphologic modifications induced by extensive construction of check-dams – especially the synergetic effect of check-dam systems – are still unclear. Taking the Loess Plateau as the application site, this project aims at (1) quantitatively studying the impact of erosion control measures (primarily check-dams) on soil erosion at different spatial and temporal scales, (2) developing an optimization-based, decision-making tool for planning the large-scale deployment of these infrastructures, and (3) deriving design principles that are applicable to both natural and urban contexts. The project adopts a multi-disciplinary approach, bridging the expertise in soil erosion and watershed planning available at ZJU and SUTD, respectively. Combining field tests, laboratory experiments, physics-based numerical simulations and optimization algorithms, the impact of individual check-dams and the synergetic effect of check-dam systems at watershed scale will be investigated.
Distributional Robust Optimization for Consumer Choice in Transportation Systems (MOE Tier 2)
Karthik Natarajan and Selin Damla Ahipasaoglu
Discrete choice models are widely used in the analysis of individual choice behavior and are applied to many fields including economics, environmental management, transportation systems, manufacturing systems, healthcare and marketing. For example, it is used in marketing research to guide product positioning, pricing, product concept testing, and is of importance in strategic and tactical planning. However, the evaluation of choice probabilities is a challenging task, except in special models such as Multinomial Logit. Simulation techniques remain the most common way to analyze choice behavior. Recently, Natarajan, Song and Teo (2009) and Mishra et. al. (2012) have proposed novel optimization based approaches as an alternative to evaluating choice probabilities. These models are distributionally robust since minimal assumptions are imposed on the distribution of the random utilities for the population of consumers. The overall aim of this project is to build on recent progress in robust optimization techniques to create theoretically sound and computationally tractable solutions for modeling consumer choice with a focus on application in systems planning. The overall scope of this project falls into the following three main research areas: (a) Statistical inference for choice models, (b) Distributionally robust route choice models and (c) Incorporating robustness in system level planning with consumer choice behavior. The theory will be developed with a view towards its applicability in areas such as transportation systems.
A Dynamical Systems Approach to Algorithmic Game Theory (MOE Tier2 Award)
The main solution concept of game theory is the notion of Nash equilibrium, which corresponds to behavioral outcomes where no agent can unilaterally deviate and strictly improve his utility. Algorithmic game theory applies tools from computer science to compute such behavioral outcomes in large decentralized settings which are inspired by Internet applications. Despite the prominence of this approach, which has already established itself as an independent scientific field, its main working hypothesis that (Nash) equilibration is the “natural” system state, has fallen under increasing scrutiny lately due to recent negative computational complexity results. In this research agenda, we move away from this assumption and instead aim to develop a general, dynamic, computational “non-equilibrium” theory to studying such decentralized systems.
Along with Christos Papadimitriou from UC Berkeley, we explore a novel approach that combines recent developments in the area of topology of dynamical systems with the computational point of view of algorithmic game theory. Instead of focusing on equilibria, a new solution concept emerges that captures more complicated and realistic behavior of agent dynamics. This concept, informally, captures (approximately) recurring behavioral trends, such as fashion cycles, market boom-bust cycles, e.t.c. The precise mathematical formulation as well as its deep mathematical significance rests upon a seminal work on topology by Conley in 1978, which is known as the fundamental theorem of dynamical systems. Although this theory has been developed quite extensively in its purely mathematical form, its practical computational implications for large decentralized systems that we care about are not well understood. By bringing together this modern theory of dynamical systems along with the latest computational and algorithmic techniques we plan to develop a more thorough understanding of the functionality and the “best design” principles for large decentralized systems.