David Lee

The emergence of COVID-19 in South Korea, and the public and private sector response to it, serves as a valuable case study for countries facing similar outbreaks. This article focuses on how Korean health officials implemented drive-through and walk-through diagnostic testing, and extensive movement and contact tracing, to identify and inform exposed members of the public. Mobile applications from both government agencies and private developers played an important role in guiding people to test

Though the technological advancement of smart city infrastructure has significantly improved urban pedestrians’ health and safety, there remains a large number of road traffic accident victims, making it a pressing current transportation concern. In particular, unsignalized crosswalks present a major threat to pedestrians, but we lack dense behavioral data to understand the risks they face. In this study, we propose a new model for potential pedestrian risky event (PPRE) analysis, using video fo

Efficient evacuation planning is important for quickly navigating people to shelters during and after an earthquake. Geographical information systems are often used to plan routes that minimize the distance people must walk to reach shelters, but this approach ignores the risk of exposure to hazards such as collapsing buildings. We demonstrate evacuation route assignment approaches that consider both hazard exposure and walking distance, by estimating building collapse hazard zones and incorpora

We present PhantomPen, a direct pen input device whose pen head is virtualized onto the tablet display surface and visually connected to a graspable pen barrel in order to achieve digital drawing free from pen occlusion and visual parallax. As the pen barrel approaches the display, the virtual pen head smoothly appears as if the rendered virtual pen head and the physical pen barrel are in unity. The virtual pen head provides visual feedback by changing its virtual form according to pen type, col

Large-scale informal recycling networks often emerge among developing economies in response to the challenges of modern urban waste accumulation. South Korea, despite its highly industrialized, developed economy, still maintains an extensive informal recycling sector made up of networks of local junk shops and individual waste pickers. As cities’ large data sources have become more widely available, the use of urban informatics in sustainable smart waste management has become more widespread. In

Building on top of an experiment in tracking the movement of trash, we tested whether viewing this sensor data would change peoples' sustainability attitudes and behaviors. We showed subjects real-time maps of trash tagged with networked GPS sensors, and surveyed them before and after seeing this information. Our results show that subjects did not significantly change their behavior in the long run, but they reported better understanding of where their trash went and how tracking technologies wo

This article describes how traffic detection cameras are plagued by lots of imaging challenges: sun glare, shadows, wet streets, snow, and fog, all of which can confuse the analytics software that controls the lights and cause endless false calls and missed calls. Affordable, high-performance thermal cameras solve all of these imaging challenges, giving traffic monitoring operator’s 24-hour uninterrupted detection of motorizied vehicles, cyclists, and pedestrians regardless of the amount of ligh

We analyze the consumer-age-specific patterns of restaurant preferences in commercial areas of Seoul, through the mining of place recommendation results from the Naver Place online service. We calculate indices for 188 distinct areas of Seoul measuring the heterogeneity of taste across age groups, and the dominance of any one age group over the general options presented to the public. Our results suggest that both high-traffic and rapidly changing commercial areas present diverse options appeali