Presentation 2008-03-23
User Context Recognition for Use in Wearable Learning Systems Based on Congestion Level Estimation of the Inside of a Train Using a Carbon Dioxide Sensor
Tomonori NAKAMURA, Takefumi OGAWA, Kiyoshi KIYOKAWA, Haruo TAKEMURA,
PDF Download Page PDF download Page Link
Abstract(in Japanese) (See Japanese page)
Abstract(in English) In this paper, we have investigated a user context recognition mechanism for a wearable system that provides a context-based uninterrupted learning environment based on congestion level estimation of the inside of a train using a carbon dioxide sensor. In our research, we measure the acceleration of a user's legs, ceiling height, and carbon dioxide level in the area to recognize the following five user conditions: sitting, standing, walking, running, and biking, the following three standing locations: on a train, on a platform, and at a crossing gate or a traffic signal, and the following two congestion levels of the inside of a train: uncrowded and crowded. The support vector machine predicts the probability of a user's context based on the power spectrum of the acceleration data, the median of the height data, and the raw carbon dioxide data. In addition, we introduce context transition tendency to achieve robust recognition of user context. We have conducted a series of experiments to evaluate our prototype. Our system was able to recognize user context during an actual commute with an accuracy of 85.8%. Also, we confirmed that the misrecognition rate that results in an interference with learning where the system gives a question the user cannot answer is extremely low (0.6%).
Keyword(in Japanese) (See Japanese page)
Keyword(in English) Wearable Learning System / Context Recognition / Accelerometer / Ultrasonic Sensor / Carbon Dioxide Sensor
Paper # MVE2007-89
Date of Issue

Conference Information
Committee MVE
Conference Date 2008/3/15(1days)
Place (in Japanese) (See Japanese page)
Place (in English)
Topics (in Japanese) (See Japanese page)
Topics (in English)
Chair
Vice Chair
Secretary
Assistant

Paper Information
Registration To Media Experience and Virtual Environment (MVE)
Language JPN
Title (in Japanese) (See Japanese page)
Sub Title (in Japanese) (See Japanese page)
Title (in English) User Context Recognition for Use in Wearable Learning Systems Based on Congestion Level Estimation of the Inside of a Train Using a Carbon Dioxide Sensor
Sub Title (in English)
Keyword(1) Wearable Learning System
Keyword(2) Context Recognition
Keyword(3) Accelerometer
Keyword(4) Ultrasonic Sensor
Keyword(5) Carbon Dioxide Sensor
1st Author's Name Tomonori NAKAMURA
1st Author's Affiliation Graduate School of Information Science and Technology, Osaka University()
2nd Author's Name Takefumi OGAWA
2nd Author's Affiliation Information Technology Center, The University of Tokyo
3rd Author's Name Kiyoshi KIYOKAWA
3rd Author's Affiliation Graduate School of Information Science and Technology, Osaka University:Cybermedia Center, Osaka University
4th Author's Name Haruo TAKEMURA
4th Author's Affiliation Graduate School of Information Science and Technology, Osaka University:Cybermedia Center, Osaka University
Date 2008-03-23
Paper # MVE2007-89
Volume (vol) vol.107
Number (no) 554
Page pp.pp.-
#Pages 6
Date of Issue