Publications

This paper studies integrating the crowd workforce into next-day home delivery services. In this setting, both crowd drivers and contract drivers collaborate in making deliveries. Crowd drivers have limited capacity and can choose not to deliver if the presented tasks do not align with their preferences. The central question addressed is: How can the platform minimize the total task fulfilment cost, which includes payouts to crowd drivers and additional payouts to contract drivers for delivering the unselected tasks by customizing task displays to crowd drivers? To tackle this problem, we formulate it as a finite-horizon Stochastic Decision Problem, capturing crowd drivers’ utility-driven task preferences, with the option of not choosing a task based on the displayed options. An inherent challenge is approximating the non-constant marginal cost of serving orders not chosen by crowd drivers, which are then assigned to contract drivers. We address this by leveraging a common approximation technique, dividing the service region into zones. Furthermore, we devise a stochastic look-ahead strategy that tackles the curse of dimensionality issues arising in dynamic task display execution and a non-linear (problem specifically concave) boundary condition associated with the cost of hiring contract drivers. In experiments inspired by Singapore’s geography, we demonstrate that choice-based crowd shipping can reduce next-day delivery fulfilment costs by up to 16.9%. The observed cost savings are closely tied to the task display policies and the task choice behaviours of drivers.

Many cities experience urban overheating from climate change and the urban heat island phenomenon. Previous studies demonstrate that parks are a potential nature-based solution to mitigate urban overheating through the ‘Park Cool Island’ (PCI) effect. PCI intensity can be measured through field measurements (FM) or remote sensing. This FM study used a network of meteorological sensors within a park and in its surrounding urban area to ascertain its PCI intensity in Singapore from January to December 2022. Consistently cooler air temperatures were found throughout a 24-h period in the park area, with mean daytime (nighttime) PCI intensity measured ~ 2.21 °C (~ 1.69 °C). A modified version of PCI (PCImodified) was developed to highlight the radiative cooling differences between the urban and park areas. PCImodified leverages on the network of sensors to preserve the spatial granularity of data, allowing for the interpolation of point data across the study area. By employing Geographical Information Science concepts, the model visualises the diurnal changes in PCImodified intensities with respect to tree height, tree density, and building height; significant cooling is positively (negatively) correlated with tree height and density (building height). This study demonstrates a comprehensive analysis of PCI and cooling intensities of parks using FM in understudied tropical urban environments.
 

Cities have long been expressions of political ideology in China and elsewhere. During China’s rapid urbanization over the past few decades, “new areas” became popular strategies to promote urban growth, following the success of Shenzhen, widely regarded as China’s first special economic zone. Today under Xi, Xiong’an New Area has become the latest “new area of national significance.” But unlike previous new areas in China, Xiong’an has become wedded to a distinct vision of the urban in Xi Jinping’s China, one in which the excesses of reform-era urbanization are controlled through new forms of affordable housing and finance, new ecological planning approaches and digitized government services. Through an analysis of the rhetoric and ideas used to promote the city, gleaned from archival analysis and financial data, this article shows how Xiong’an has become a showcase for a new ideology of the urban under Xi Jinping.

The idea of right-sizing, or the process of adjusting the size of a city to maximise the efficient use of resources, has traditionally been used in strategic management and the resizing of shrinking cities to promote efficient urban development. Concurrently, in contemporary discourse, the sizing of smart cities has emerged as a critical topic, as size impacts the implementation of smart initiatives. Smaller cities offer the advantage of serving as cost- effective testing grounds for innovative solutions; however, they also need to be sizeable enough to attract private investments and build a robust smart city ecosystem. In this paper we demonstrate how in the context of smart city planning and governance in Southeast Asia, different actors are adopting new spatial strategies to address the sizing question. The idea of right-sizing requires rethinking in the context of smart city because it captures how effectively cities are scaled to balance technological innovations with socio-economic and administrative demands. Through three case studies from Southeast Asia, we analyse three distinct smart city right-sizing strategies: dispersal, zoning, and merging. By examining these, the paper highlights the complexities and nuances in determining the right size of a smart city across discrete contexts.

This article considers the ways in which the material infrastructures of China’s Belt and Road Initiative (BRI) intersect with other infrastructural formations, and how the resulting overlaps can trigger processes of what I call “infrastructural splintering”. These processes cause infrastructure to be experienced in differentiating ways, creating divisive politics where there might once have been unity. Embracing these politics as an analytical starting point undermines the techno-material stability of the BRI, and reveals its more-than-material affects. I illustrate these ideas by developing a case study of the effects of the China-backed Colombo Port City project on Catholic fishing communities that are dependent upon the aquatic commons for survival. The construction of the Port City has brought about significant aquatic pollution and ecosystem destruction, and public erasure by Colombo’s political elites. Complicating matters is the dominance of the Catholic Church in Sri Lanka’s littoral spaces, which has become divided by a universalist politico-ecological consciousness imposed by the Vatican, a corruptible local hierarchy, and environmental activists that engage communities by working through the Church’s sacred infrastructures. By working through these processes of infrastructural splintering, I consider how the BRI has caused Sri Lanka’s littoral spaces to face increasingly fractious futures.
 

Ageing in place is the ability to remain in one’s community, where living conditions foster a sense of attachment that enhances holistic well-being. To facilitate this, both the built and social environments within which the home is nested must be conducive to successful ageing. This paper deconstructs the merits of ageing in place, specifically how attachment to the lived environment contributes to holistic well-being. We analysed data from 6020 participants in the Singapore Life Panel® using path models, where we examined three dimensions of ageing in place: place identity, continuity, and social inclusion. Five path analyses show that two dimensions of ageing in place mediated the relationship between well-being and factors such as social isolation, number of close neighbours, social support, and satisfaction with amenities, but not living arrangements. Social inclusion consistently showed no significant relationship with well-being across all models. These findings suggest that the quality of social connections, rather than physical living arrangements, is important for well-being, and that social inclusion needs to be more appropriately contextualised. Our study contributes to policy discussions on how supporting older adults to age in place can enhance their overall well-being.

In recent years, China has pivoted towards a global leadership role in mitigating and adapting to climate change. Notwithstanding the complex political economic reasons underlying China's global leadership aspirations, we are interested in seeing whether the associated national discourse championed by the state increases domestic support for climate policy. That is, do China's international leadership aspirations foster a unifying sense of national pride among the domestic population, thereby lending support to the legitimacy of the state and expediting the implementation of costly domestic climate policies? To test our hypothesis, we enumerated a vignette experiment embedded with conjoint analysis to a nationally representative sample (n = 4788). We found no evidence that exposure to China's global leadership aspirations increased domestic support for national-level climate policy, as proxied by a carbon tax. Indeed, we found that exposure to China's global climate leadership aspirations decreased domestic support for a carbon tax under certain scenarios. Our findings demonstrate a potential disconnect between global and local climate policy discourses and suggest that China's policymakers need to exercise caution in ensuring that their global climate leadership aspirations do not come at the expense of decreased domestic support for the national-level policies required to meet China's goal of carbon neutrality by 2060.
 

This paper critically assesses the complex interplay between urban transitions of digitisation and sustainability. Building on a mixed-method research design, we unpack the challenges of decarbonising digital infrastructure while attending to urban sustainability goals in a land- and water-scarce country facing significant physical climate risks. We identify transferrable lessons on the economic, technological, and environmental synergies and trade-offs behind data centre development and argue that stewarding the global data centre sector towards sustainability requires an ecosystem-wide approach. We identify implementation gaps across five key dimensions: technological innovation, policy and regulation, finance, infrastructure, and people. We find that the progress and uptake of sustainability initiatives are often impeded by risk-averse DC operators, who are most concerned with real and perceived risks of downtime. We conclude with recommendations for data centre stakeholders to align the low-carbon transition of the data centre sector with broader objectives of climate resilience, smart city development, and sustainable finance.

Identifying gaps in urban climate change assessment is crucial for developing the new Intergovernmental Panel on Climate Change (IPCC) special report on cities. To bridge the gap between the understanding of local interventions and global climate goals, we call for the strengthening of assessment tools such as urban typologies, case study synthesis and big geospatial data studies. We sort research gaps into five overarching themes: (1) urban form, (2) data and artificial intelligence, (3) policies and governance, (4) system transformation and (5) potentials, costs and losses. Using these methods for categorizing and analyzing cities based on shared characteristics will enable the tailoring and scaling of local climate solutions to global contexts.

Schools play a pivotal role in guiding students to become certain types of people. International schools strive to educate global citizens who are adaptable and culturally curious. As part of this mission, international schools encourage the celebration of religious diversity through institutional accommodation and school celebrations. The eclectic mix of belonging and becoming encountered in international schools can lead to the creation of a more-than-national sense of identity. For Indian expatriates in Singapore, this becomes particularly complex due to degrees of attachment to India, feelings of belonging within Singapore, and the pursuit of a transnational ‘Global Indian’ identity. Drawing on 53 interviews with students, teachers, and school administrators from international schools in Singapore, we explore how the teaching and performance of Indian culture, specifically religious festivals, can shape the formation of more-than-Indian citizenship pathways.