Jaewoo Chung

Indoor location sensing using geo-magnetism

We present an indoor positioning system that measures location using disturbances of the Earths magnetic field caused by structural steel elements in a building. The presence of these large steel members warps the geomagnetic field in a way that is spatially varying but temporally stable. To localize, we measure the magnetic field using an array of e-compasses and compare the measurement with a previously obtained magnetic map. We demonstrate accuracy within 1 meter 88% of the time in experiments in two buildings and across multiple floors within the buildings. We discuss several constraint techniques that can maintain accuracy as the sample space increases.

Going my way: a user-aware route planner

Going My Way is a mobile user-aware route planner. The system collects GPS data of a users everyday locations and provides directions from an automatically selected set of landmarks that are close to the destination, informed by the users usual travel patterns. In this paper, we present a brief description of the system, the results of a preliminary experiment in memory and recognition of landmarks, in addition to the results of a user evaluation of the system.

Exploring Centrality for Message Forwarding in Opportunistic Networks

In opportunistic networks, centrality characterizes a nodes capability to act as a communication hub. In this paper, we provide an in-depth study of choosing effective centrality metrics for message forwarding in bandwidth-limited opportunistic networks. Based on this study, we propose a destination-unaware forwarding algorithm that accounts for the popularity of a node and the contact durations between nodes. We evaluate the algorithm on two experimental human mobility traces. The simulation results show that the proposed algorithm achieves higher system throughput while maintaining a lower forwarding cost compared with several known destination-unaware forwarding schemes.

Guiding Light: Navigation assistance system using projection based augmented reality

We introduce an indoor navigation assistance system, Guiding Light. The system uses projection based augmented reality to provide way-finding information using handheld projectors on mobile phones. In this version of the system, we use a combination of business cards, maps and building interiors as venues for augmenting information to assist users with navigation guidance.

Topic spotting common sense translation assistant

Our Translation Assistant applies common sense logic to the problem of translating speech in real time from one language to another. Using speech recognition combined with a software translator to do word-by-word translation is not feasible because speech recognition is notorious for poor results. Word-by-word translation requires grammatically correct input to translate accurately. Therefore, translation of speech that is potentially already fraught with errors is not expected to be good. Our Translation Assistant works around these problems by using the context of the conversation as a basis for translation. It takes the location and the speaker as input to establish the circumstances. Then it uses a common sense knowledge network to do topic-spotting using key words from the conversation. It only translates the most likely topics of conversation into the target language. This system does not require perfect speech recognition, yet enables end-users to have a sense of the conversation.

iLight: information flashlight on objects using handheld projector

Handheld Projectors are novel display devices developed recently. In this paper we present iLight, Information flashLight, which is based on the ongoing research project Guiding Light [9] using a handheld projector. By using a handheld projector with a tiny camera attached on it, system can recognize objects and augment information directly on them. iLight also present a interaction methodology on handheld projector and a novel real-time interactive experiences among users.

My Second Bike: A TV-Enabled Social and Interactive Riding Experience

In this paper, we propose a novel concept for a social TV application targeting the demographic of viewers enjoying live sports events, such as road bicycle racing. We intend to enhance the viewing experiences of spectators with sensor-fitted bikes tied to an interactive biking environment on television. The system enables a new form of personalized, physical, and virtual-reality interaction between viewers and a TV program, as well as interactions within or between communities of friends. We also describe a prototype we have implemented to demonstrate the feasibility of our idea. The prototype, My Second Bike, uses a 3D mirrored world environment (Google Earth) to visually represent participating spectators, competing athletes and outdoor bikers. We contend that the system has the potential to attract and support a large user base on account of its scalability ease of deployment and ability to promote audience participation in live sports events on TV.

Are We There Yet? User-Centered Temporal Awareness

Its not unreasonable to think that the technologies we use in our daily lives could help us make these sorts of decisions. For example, analysis of computer usage patterns can reveal our probable availability to colleagues. But, even better, it should be possible for devices to make some of these decisions for us while still leaving us with a comfortable level of control. We refer to such systems as exhibiting temporal awareness. One way to realize temporally aware computing in everyday use is via wearable devices. Such devices could collect time-related information from the items and environments we interact with and create a personal temporal model. They could then use this information to change our behavior.An example of temporal awareness in action, the AreWeThereYet? Player is a digital audio player that can compose a program of audio media likely to fit within the users available listening time. AWTY estimates this time using the listeners current location and predicted destination as well as some knowledge of previous journeys.