Research

SmokeSense: A study about smoking behavior

SmokeSense aims to understand habit-related problems, such as smoking, alcohol, and diet. Elaborating mobile sensing, the study monitors people's behavior in daily basis, and assess smoking cue, social cue, geographic cue craving level and lapses. 

Buzz: Injecting Life into a Toys

Buzz is a seamless mobile machine learning application that continuously understands user context.  Buzz envisions a future in which smartphones can be inserted into toys to make them interactive to children. The work aims to enable smart toy that interacts with children, understands their development, and diagnoses potential illness such as autism. The work collects sensing data from mobile application, and conducts gesture recognition. 

Finding Lost Children and Device

I am very interesting in searching the lost children and objects. 
Finding missing children is a very important problem concerning not only parents but also to our society. Finding missing child had been inherently a collaborative searching task. Once a child is missing, people might have partial but crucial information about child’s whereabouts. Collecting those information from witness can retrieve the location of the missing child. The project provides a new intuitive way for parent to search their children. (a web site and application are coming soon.)
The project also provides a  'warm/cold' game-based easy way to find a lost device (FindingMiMo).

Indoor Location-based Service (iLBS)

Indoor pedestrian tracking system is still hot issue. Indoor pedestrian tracking extends LBS (location-based services) into indoor environment. The research mainly aims to enable indoor LBS by serving a participatory service platform using crowdsourced indoor map construction. The project includes an iLBS server platform, an autonomous indoor map builder, organic indoor map maintenance mechanism, and iLBS module on smartphone device. 

LifeMap

I am currently working with Yohan Chon and others on LifeMap, a smartphone-based context provider for providing advanced location-based service for mobile users and human-centric mobile sensing. LifeMap fuses accelerometer, digital compass, Wi-Fi and GPS to do tracking and to automatically identify points of interest with room-level accuracy. LifeMap provides human mobility with user context for research communities. For more details, visit the web site (http://lifemap.yonsei.ac.kr).

RETOS: Micro OS for WSN

RETOS is the operating system for sensor nodes. RETOS provides a multithreaded programming interface, system resiliency, kernel expendability with dynamic reconfiguration, and wireless sensor network oriented network abstraction. I have been involved in this project and developed an extensible kernel and remote update mechanism. The web site is closed. (http://mobed.yonsei.ac.kr/retos). 

YMAC: MAC protocols for WSN 

YMAC is an energy efficient multi-channel MAC protocol for wireless sensor networks. The goal is to achieve both high performance and energy efficiency under diverse traffic conditions. In contrast to most of previous multi-channel MAC protocols for WSNs, we implemented Y-MAC on a real sensor node platform and conducted extensive experiments to evaluate its performance. 

Address Autoconfiguration Protocols for 6LowPan

The project is exploring autonomous address autoconfiguration protocols to assign network nodes with unique address in ad-hoc network especially with reduced function device. I proposed Spectrum, LISSA and ColorCode which are stateless, stateful and hybrid autoconfiguration methods, respectively.