Shwetak Patel - Academia.edu (original) (raw)

Papers by Shwetak Patel

Lecture Notes in Computer Science, 2006

Implicit in much research and application development for mobile phones is the assumption that th... more Implicit in much research and application development for mobile phones is the assumption that the mobile phone is a suitable proxy for its owner's location. We report an in-depth empirical investigation of this assumption in which we measured proximity of the phone to its owner over several weeks of continual observation. Our findings, summarizing results over 16 different subjects of a variety of ages and occupations, establish baseline statistics for the proximity relationship in a typical US metropolitan market. Supplemental interviews help us to establish reasons why the phone and owner are separated, leading to guidelines for developing mobile phone applications that can be smart with respect to the proximity assumption. We show it is possible to predict the proximity relationship with 86% confidence using simple parameters of the phone, such as current cell ID, current date and time, signal status, charger status and ring/vibrate mode.

We have developed an approach for whole-house gross movement and room transition detection throug... more We have developed an approach for whole-house gross movement and room transition detection through sensing at only one point in the home. We consider this system to be one member of an important new class of human activity monitoring approaches based on what we call infrastructure mediated sensing, or "home bus snooping." Our solution leverages the existing ductwork infrastructure of central heating, ventilation, and air conditioning (HVAC) systems found in many homes. Disruptions in airflow, caused by human interroom movement, result in static pressure changes in the HVAC air handler unit. This is particularly apparent for room-to-room transitions and door open/close events involving full or partial blockage of doorways and thresholds. We detect and record this pressure variation from sensors mounted on the air filter and classify where certain movement events are occurring in the house, such as an adult walking through a particular doorway or the opening and closing of a particular door. In contrast to more complex distributed sensing approaches for motion detection in the home, our method requires the installation of only a single sensing unit (i.e., an instrumented air filter) connected to an embedded or personal computer that performs the classification function. Preliminary results show we can classify unique transition events with up to 75-80% accuracy.

Proceedings of the 17th annual ACM symposium on User interface software and technology - UIST '04, 2004

Powerful mobile devices with minimal I/O capabilities increase the likelihood that we will want t... more Powerful mobile devices with minimal I/O capabilities increase the likelihood that we will want to annex these devices to I/O resources we encounter in the local environment. This opportunistic annexing will require authentication. We present a sensor-based authentication mechanism for mobile devices that relies on physical possession instead of knowledge to setup the initial connection to a public terminal. Our solution provides a simple mechanism for shaking a device to authenticate with the public infrastructure, making few assumptions about the surrounding infrastructure while also maintaining a reasonable level of security. Figure 1: Prototype of a Motorola i95cl instrumented with a 2-axis accelerometer.

Proceedings of the 8th international ACM SIGACCESS conference on Computers and accessibility - Assets '06, 2006

Finding lost items is a common problem for the visually impaired and is something that computing ... more Finding lost items is a common problem for the visually impaired and is something that computing technology can help alleviate. In this paper, we present the design and evaluation of a mobile solution, called FETCH, for allowing the visually impaired to track and locate objects they lose frequently but for which they do not have a specific strategy for tracking. FETCH uses devices the user already owns, such as their cell phone or laptop, to locate objects around their house. Results from a focus group with visually impaired users informed the design of the system. We then studied the usability of a laptop solution in a laboratory study and studied the usability and usefulness of the system through a one-month deployment and diary study.

Proceedings of the 27th international conference on Human factors in computing systems - CHI 09, 2009

Despite increased knowledge about how Information and Communications Technologies (ICTs) are used... more Despite increased knowledge about how Information and Communications Technologies (ICTs) are used to support religious and spiritual practices, designers know little about how to design technologies for faith-related purposes. Our research suggests incorporating sacred imagery into technospiritual applications can be useful in guiding development. We illustrate this through the design and evaluation of a mobile phone application developed to support Islamic prayer practices. Our contribution is to show how religious imagery can be used in the design of applications that go beyond the provision of functionality to connect people to the experience of religion.

Lecture Notes in Computer Science, 2009

We present a system, called PL-Tags, for detecting the presence of batteryless tags in a building... more We present a system, called PL-Tags, for detecting the presence of batteryless tags in a building or home through the power lines. The excitation (or interrogation) and detection of these tags occurs wirelessly entirely using the powerline infrastructure in a building. The PL-Tags proof-of-concept consists of a single plug-in module that monitors the power line for the presence of these tags when they are excited. A principal advantage of this approach is that it requires very little additional infrastructure to be added to a space, whereas current solutions like RFID require the deployment of readers and antennas for triggering tags. An additional benefit of PL-Tags is that the tags are wirelessly excited using an existing phenomenon over the power line, namely electrical transient pulses that result from the switching of electrical loads over the power line. We show how these energy rich transients, which occur by simply turning on a light switch, fan, television, etc., excite these tags and how they are detected wirelessly over the power line. We contend that the PL-Tag system is another class of potential batteryfree approaches researchers can use for building pervasive computing applications that require minimal additional infrastructure.

Lecture Notes in Computer Science, 2007

Activity sensing in the home has a variety of important applications, including healthcare, enter... more Activity sensing in the home has a variety of important applications, including healthcare, entertainment, home automation, energy monitoring and post-occupancy research studies. Many existing systems for detecting occupant activity require large numbers of sensors, invasive vision systems, or extensive installation procedures. We present an approach that uses a single plug-in sensor to detect a variety of electrical events throughout the home. This sensor detects the electrical noise on residential power lines created by the abrupt switching of electrical devices and the noise created by certain devices while in operation. We use machine learning techniques to recognize electrically noisy events such as turning on or off a particular light switch, a television set, or an electric stove. We tested our system in one home for several weeks and in five homes for one week each to evaluate the system performance over time and in different types of houses. Results indicate that we can learn and classify various electrical events with accuracies ranging from 85-90%.

Ways of Knowing in HCI, 2014

Lecture Notes in Computer Science, 2010

Indoor location tracking systems have been a major focus of ubiquitous computing research, and th... more Indoor location tracking systems have been a major focus of ubiquitous computing research, and they have much promise to help in collecting objective, real time data for applications and supporting studies. However, due to their typically difficult and time consuming installation process, few have explored the extent to which they can be used by non-experts. In this research, we studied how one location tracking system, PowerLine Positioning, could be used by non-technology expert rehabilitation researchers to study the mobility patterns of wheelchair users in their homes. We determined that indoor location tracking systems are not only usable by non-experts, but they can also be useful in allowing them to achieve their own research goals of obtaining objective mobility data. Based on the results, we provide areas for future exploration and implications for designers of location-based and other types of sensing systems which aim to be end-user deployable.

ACM SIGMOBILE Mobile Computing and Communications Review, 2015

Sound is an important medium in our lives, but its ephemeral nature can be problematic when peopl... more Sound is an important medium in our lives, but its ephemeral nature can be problematic when people cannot recall something they heard in the past. Motivated by everyday conversational breakdowns, we present the design of a continuous, near-term audio buffering application: the Personal Audio Loop (PAL). PAL was designed as a truly ubiquitous service to recover audio content from a person's recent past. Initial brainstorming and prototyping for PAL revealed major aspects of the design space that require further investigation, including potential usefulness in everyday life, the level of ubiquity required, the usability features for any instantiation of the service, and the social and legal considerations for potential deployment. We present a design of PAL, informed by a controlled laboratory study, diary study, and examination of pertinent legislation. We conclude with an analysis of the results and some initial observations of the deployment of a prototype developed for a Motorola i730 handset.

Gerontechnology, 2010

ISSUE To date, efforts have addressed a single aspect of older adults' health, focusing on one or... more ISSUE To date, efforts have addressed a single aspect of older adults' health, focusing on one or more specific functional, physiological, social, spiritual or cognitive parameters. Methodologies are lacking that address the holistic and multidimensional assessment of health and wellness. The assessment of health, which is multidimensional in nature, is a critical component in maintaining a high level of well-being and independence for older adults. Identifying problems while they are still small can provide a window of opportunity for interventions that will alleviate problem areas before they become catastrophic. CONTENT The challenge is to assess and integrate various data sources that provide a comprehensive assessment of older adults' wellbeing and customize assessment based on individual needs. Technology applications may enable non-obtrusive monitoring and assessment of physiological, functional, cognitive or other parameters. Another challenge is to explore how to best visualize and display information about wellness without burdening health care professionals with large amounts of data but rather enhance clinical decision making. We will be discussing approaches to capture, integrate and analyze data sets from different sources and address the challenges of obtrusiveness and privacy considerations. We will discuss shared decision making that includes both formal and informal caregivers, as well as the older adults, in the decision making process as informed and empowered participants. STRUCTURE George Demiris will provide a conceptual framework of wellness for older adults and shared decision making, and discuss current experience with the HEALTH-E project in Seattle that uses diverse technologies (including a telehealth kiosk, a gait assessment platform and brain training software) to capture and visualize older adults' wellness in an independent retirement community. Stephen Thielke will present how real-time geospatial range can be utilized by researchers and clinicians to objectively measure functional status and assist with symptom management. Katarzyna Wilamowska will discuss a novel imaging analysis approach that when used longitudinally provides insight into patterns of well-being. Oleg Zaslavsky will discuss the role of technology in assessing and predicting frailty in community dwelling older adults. Blaine Reeder will discuss how current work presented in this symposium can inform the design of built environments for older adults to promote wellness and highlight public health policy implications. Following the individual presentations, Hilaire Thompson will lead a discussion focusing on trends in technology use for shared decision making. CONCLUSION Technology can empower older adults and enhance the decision making process by increasing access to information and our understanding of wellness. Technology should be designed to minimize obtrusiveness and address privacy concerns, following actual needs and meaningful clinical models of care. . Real-time geospatial range for geriatric assessment. Gerontechnology 2010;9(2):168-169; doi:10.4017/gt.2010.09.02.120.00 Purpose What people do is strongly linked to where they are and where they go, and measuring location and movements can inform a great deal about how people function in their natural environments. Novel microprocessor technologies, using portable sensors, can gather such data. Such technologies have the potential to alter how patients, clinicians, and researchers measure and interpret functioning, allowing better assessments of health status and more targeted treatments for disabling health conditions. Such measurements are especially important for the care of adults who are frail or at risk for frailty. One of the key challenges in applying the concept of frailty in clinical settings is that it is a composite, multifactorial, and 169 Spring 2010

This work demonstrates the feasibility of using existing in-home electrical wiring to extend the ... more This work demonstrates the feasibility of using existing in-home electrical wiring to extend the operational range of certain wireless devices. Specifically, a wireless keyboard operating at 27 MHz, which has an operational range of 1.5 -2 meters on its own, was extended to work throughout a 3-story 4,000 square foot / 371 square meter home by coupling the antenna port on its receiver to the power lines. Coupling between the keyboard and the power lines occurred over the air, and coupling at the receiver was accomplished capacitively by simply wrapping a wire connected to the receiver's antenna port several times around a standard electrical device cord plugged into a wall socket. This phenomenon of the power line as a communications infrastructure for inexpensive and lowpower wireless devices has a variety of interesting potential avenues of research in the home.

Page 1. 1028 Chapter LXI Designing a Ubiquitous Audio-Based Memory Aid Shwetak N. Patel Georgia I... more Page 1. 1028 Chapter LXI Designing a Ubiquitous Audio-Based Memory Aid Shwetak N. Patel Georgia Institute of Technology, USA Khai N. Truong University of Toronto, Canada Gillian R. Hayes Georgia Institute of Technology, USA ...