My research contributes to the fields of Human Computer Interaction (HCI) and Ubiquitous Computing (Ubicomp). Within these fields, I have focused on Health Informatics, Social Computing, and Mobile Computing. I am passionate about studying how technology can empower users to capture and share information in ways that are privacy-sensitive, reflective, and socially meaningful for connecting with others.

health informatics

  • Estrellita: empowering caregivers of preterm infants

    Preterm birth is often associated with long-term health impairments. Because of these health concerns, caring for preterm infants can often be an stressful experience for parents. To address this challenge, we've created Estrellita, a system that: (1) helps parent record, communicate, and understand data collected about their infants on a frequent basis and (2) improves parent and clinician feelings of efficacy and quality of care.

    Estrellita consists of two parts: a mobile application for caregivers and a web portal for clinicians. Using the mobile application, parents can record observations of daily living (ODLs) for their infant and for themselves, share their data with clinical providers, and visualize a history of their ODL data. Through the website, healthcare providers can interact with the parent and keep abreast with the infant's ODLs through a series of simple visualizations and data summaries.

    Tang, K.P., Cheng, K.G., Hirano, S., Nagel, M., Baker, D., and Hayes, G.R. (2011). Addressing the Design Challenges for a Clinically-Informed Data Capture Tool Targeted for Caregivers of Premature Infants. Workshop on Interactive Systems in Healthcare (WISH '11).
    [local pdf] [talk]
  • Memory Karaoke: an episodic memory tool for the elderly

    Memory Karaoke is a location-aware mobile application inspired by clinically-based memory therapies that aim to exercising a person's memory through storytelling. This is done by stimulating a person's episodic memory as they relive, reminisce, and retell stories about their past events while observing past contextual cues captured by the mobile device. We developed and evaluated Memory Karaoke with older adults to determine its potential to serve as an effective memory aid.

    Tang, K.P., Smith, I.E., Hong, J.I., Ha, A., and Satpathy, L. (2007). Memory Karaoke: Using a Location-Aware Mobile Reminiscence Tool to Support Aging in Place. Proceedings of the 9th International Conference on Human Computer Interaction with Mobile Devices and Services (MobileHCI '07).
    [official pdf] [local pdf]

social computing


mobile computing


  • Hitchhiking: anonymous participatory sensing of busyness

    Hitchhiking is a privacy-sensitive manner way of building a certain class of location-based services. Bustle is an example of a Hitchhiking application that can answer questions like "How busy is it at the cafe?" and "How long are the lines at the airport?" Bustle works by counting the number of wireless devices in an area and using that count to estimate the number of people.

    Tang, K.P., Fogarty, J., Keyani, P., and Hong, J.I. (2006). Putting People in their Place: An Anonymous and Privacy-Sensitive Approach to Collecting Sensed Data in Location-Based Applications. Proceedings of the ACM Conference on Human Factors in Computing Systems (CHI '06).
    [official pdf] [local pdf]
    Fogarty, J., Hong, J.I., Keyani, P., and Tang, K.P. (2006). Anonymous and Privacy-Sensitive Collection of Sensed Data in Location-Based Application. Workshop on Mobile Social Software at the ACM Conference on Human Factors in Computing Systems (CHI '06).
    [local pdf]
    Tang, K.P., Fogarty, J., Keyani, P., and Hong, J.I. (2006). Bustle: Using Hitchhiking to Monitor Meaningful Locations. Proceedings of the 7th IEEE Workshop on Mobile Computing Systems and Applications (HotMobiles '06).
    [official pdf] [local pdf]
  • GSM-based localization for mobile phones

    This projects looks at triangulating a user's location and activity information based on GSM fingerprinting. Using this technique, we can detect the places that people visit without using GPS, and can achieve median localization accuracies of 5 and 75 meters for indoor and outdoor environments, respectively. We've also developed algorithms for detecting whether a GSM mobile phone is moving. These algorithms, in early experiments, show excellent promise and require nothing from the mobile phone other than radio signals that the phone must have to perform its normal function.

    Varshavsky, A., Chen, M., de Lara, E., Froehlich, J., Haehnel, D., Hightower, J., LaMarca, A., Potter, F., Sohn, T., Tang, K.P., and Smith, I. (2006). Are GSM phones THE solution for localization? Proceedings of the 7th IEEE Workshop on Mobile Computing Systems and Applications (HotMobile '06).
    [official pdf] [local pdf]
    Smith, I. , Chen, M., Varshavsky, A., Sohn, T., and Tang, K.P. (2005). Algorithms for Detecting Motion of a GSM Mobile Phone. Workshop on Location Awareness and Community at the European Conference on Computer-Supported Cooperative Work (ECSCW '05).
    [local pdf]

  • eWatch: context-aware wearable computing

    The eWatch prototype senses a user's activities based on its built-in accelerometer, temperature, light, and microphone sensors. The accelerometers and microphone provide input data for its interruptibility model. Depending on a message's importance and the user's interruptibility, different vibration and visual notification patterns are sent to the user. The eWatch is transparently integrated into the user's environment as a wearable computing device and can communicate via Bluetooth to other devices.

    Smailagic, A., Siewiorek, D.P., Maurer, U., Rowe, A., and Tang, K.P. (2005). eWatch: Context Sensitive System Design Case Study. Proceedings of IEEE Computer Society Annual Symposium on VLSI (ISVLSI '05).
    [official pdf] [local pdf]
    Smailagic, A., Siewiorek, D.P., Maurer, U., Rowe, A., and Tang, K.P. (2005). A Context-Specific Electronic Design and Prototyping Course. Proceedings of the 2005 IEEE International Conference on Microelectronic Systems Education (MSE '05).
    [official pdf] [local pdf]
  • Zebranet: peer-to-peer ad hoc sensor networks

    ZebraNet is an inter-disciplinary project between Biology & Computer Science. On the computer systems side, ZebraNet is studying power-aware, position-aware computing & communication systems. Namely, the goals are to develop, evaluate, implement, and test systems that integrate computing, wireless communication, and non-volatile storage along with global positioning systems (GPS) and other sensors.

    Tang, K.P. (2002). ZnetVis: ZebraNet Information Visualization Interfaces (for Ad-Hoc Peer-to-Peer Sensor Networks). Undergraduate Thesis. Princeton University, Department of Electrical Engineering.
    Project Website: Zebranet
    Press: Princeton ELE Dept, BBC Radio4, Princeton Weekly Bulletin

past projects

  • Predicting a programmer's interruptibility

    The computer and communication systems that office workers currently use tend to interrupt at inappropriate times or unduly demand attention because they have no way to determine when an interruption is appropriate. Sensor-based statistical models of human interruptibility offer a potential solution to this problem. Prior work to examine such models has primarily reported results related to social engagement, but it seems that task engagement is also important. Using a sensor-based statistical approach to model human interruptibility, we examined task engagement by studying programmers working on a realistic programming task and empirically determining their interruptibility during various types of programming tasks.

    Fogarty, J., Ko, A.J., Aung, H.H., Golden, E., Tang, K.P., and Hudson, S.E. (2005). Examining Task Engagement in Sensor-Based Statistical Models of Human Interruptibility. Proceedings of the ACM Conference on Human Factors in Computing Systems (CHI '05).
    [official pdf] [local pdf]

  • MEI: cross-language information retrieval

    Mandarin-English Information (MEI) is a system whereby English speakers can find audio broadcasts in Mandarin Chinese that are relevant to their interests, without knowing Chinese. MEI uses written queries to search spoken documents (cross-media) between English and Mandarin Chinese (cross-language). Our research focus is on the integration of speech recognition and machine translation technologies in the context of translingual speech retrieval.

    Meng, H., Chen, B., Khudanpur, S., Levow, G., Lo, W., Oard, D., Schone, P., Tang, K.P., Wang, H., and Wang, J. (2004). Mandarin-English Information (MEI): Investigating Translingual Speech Retrieval. Computer Speech and Language, 18(2), pp. 163-179.
    [official pdf] [local pdf]
    Meng, H., Lo, W.K., Chen, B., and Tang, K.P. (2001). Generating Phonetic Cognates to Handle Named Entities in English-Chinese Cross-Language Spoken Document Retrieval. Proceedings of the IEEE Workshop on Automatic Speech Recognition and Understanding (ASRU '01).
    [official pdf] [local pdf]
    Meng, H., Chen, B., Khudanpur, S., Levow, G. Lo, W.K., Oard, D., Schone, P., Tang, K.P., Wang H.M., and Wang, J. (2001). Mandarin-English Information (MEI): Investigating Translingual Speech Retrieval. Proceedings of the 2001 Human Language Technology Conference (HLT '01).
    [official pdf] [local pdf]
    Meng, H., Chen, B., Grams, E., Khudanpur, S., Levow, G., Lo, W.K., Oard, D., Schone, P., Tang, K.P., Wang H.M., and Wang, J. (2000). Mandarin-English Information (MEI): Investigating Translingual Speech Retrieval. Johns Hopkins University, Center for Language and Speech Processing.
    [local pdf] [project website]