Anthony LaMarca's research while affiliated with Intel and other places

Publications (107)

Conference Paper
We describe the design of a hybrid system -- a combination of a Dynamic Graphical Model (DGM) with a Deep Neural Network (DNN) -- to identify activities performed during synthetic biology experiments. The purpose is to provide real-time feedback to experimenters, thus helping to reduce human errors and improve experimental reproducibility. The data...
Conference Paper
Full-text available
Always-on continuous sensing apps drain the battery quickly because they prevent the main processor from sleeping. Instead, sensor hub hardware, available in many smartphones today, can run continuous sensing at lower power while keeping the main processor idle. However, developers have to divide functionality between the main processor and the sen...
Conference Paper
Full-text available
Indoor object localization can enable many ubicomp applications , such as asset tracking and object-related activity recognition. Most location and tracking systems rely on either battery-powered devices which create cost and maintenance issues or cameras which have accuracy and privacy issues. This paper introduces a system that is able to detect...
Conference Paper
Every year, loose objects inside cars during crashes cause hundreds of serious injuries and even deaths. In this paper, we describe findings from a study of 25 cars and drivers, examining the objects present in the car cabin, the reasons for them being there, and driver awareness of the potential dangers of these objects. With an average of 4.3 pot...
Article
The four papers in this special section are extended versions of papers presented at the Seventh Annual International Conference on Mobile Systems, Applications, and Services (MobiSys 2009), held in June 2009 in Krakow, Poland.
Conference Paper
Ensemble is a system that uses a collection of trusted personal devices to provide proximity-based authentication in pervasive environments. Users are able to securely pair their personal devices with previously unknown devices by simply placing them close to each other (e.g., users can pair their phones by just bringing them into proximity). Ensem...
Conference Paper
We introduce Whack Gestures, an inexact and inattentive interaction technique. This approach seeks to provide a simple means to interact with devices with minimal atten- tion from the user - in particular, without the use of fine motor skills or detailed visual attention (requirements found in nearly all conventional interaction techniques). For mo...
Article
Securing interactions between devices that do not know each other a priori is an important and challenging task. We present Amigo, a technique to authenticate co-located devices using knowledge of their shared radio environment as proof of physical proximity. We present evaluation results that show that our technique is robust against a range of pa...
Conference Paper
We present Bonfire, a self-contained mobile computing system that uses two laptop-mounted laser micro-projectors to project an interactive display space to either side of a laptop keyboard. Coupled with each micro-projector is a camera to enable hand gesture tracking, object recognition, and information transfer within the projected space. Thus, Bo...
Article
Full-text available
Activity-aware systems have inspired novel user interfaces and new applications in smart environments, surveillance, emergency response, and military missions. Systems that recognize human activities from body-worn sensors can further open the door to a world of healthcare applications, such as fitness monitoring, eldercare support, long-term preve...
Book
Advances in electronic location technology and the coming of age of mobile computing have opened the door for location-aware applications to permeate all aspects of everyday life. Location is at the core of a large number of high-value applications ranging from the life-and-death context of emergency response to serendipitous social meet-ups. For e...
Chapter
In this chapter, we describe the various systems that use ultrasound and infrared light to perform localization. This may seem like an odd pairing, as light and sound have very different properties. What they have in common, however, is that while they move freely in open space, light and sound are both largely blocked by the materials such as wall...
Conference Paper
Full-text available
Recent advances in small inexpensive sensors, low-power processing, and activity modeling have enabled applications that use on-body sensing and machine learning to infer people's activities throughout everyday life. To address the growing rate of sedentary lifestyles, we have developed a system, UbiFit Garden, which uses these technologies and a p...
Chapter
The NAVSTAR Global Positioning System, or GPS,1 is by far the most widely used location technology. GPS is used in numerous civilian applications including, shipping, street navigation, recreational boating, ground surveying, and many more. The market for GPS products and services was estimated at 15 billion euros in 2001 and is expected to grow to...
Chapter
This lecture has presented an overview of the most common technologies and techniques that are used to estimate location. Figure 9.1 summarizes the accuracy and coverage of these technologies. We close this lecture with a discussion of some of the issues which still present challenges to the developers of location-enhanced applications and systems....
Chapter
Thus far, we have focused on describing the most widely deployed, general-purpose approaches for locating devices, objects, and mobile users. While the location technologies we have described thus far vary in cost, coverage, and accuracy, all are used in commercial location systems, and all have reached wide-scale adoption in one or more applicatio...
Chapter
Many of the systems we have presented can perform better in practice than their nominal single-reading accuracy. That is because people and devices are often stationary or moving at slow speed. This means that location systems commonly get dozens, if not hundreds, of opportunities to perform localization, and these results can be combined for great...
Chapter
In this chapter, we examine a wide variety of application domains, ranging from the life-and-death context of emergency response to serendipitous social meet-ups, in which location-aware devices are used. We describe both emerging and well-established applications that make use of nearly all of the location technologies we have described thus far....
Conference Paper
Users' ability to accurately recall frequent, habitual activities is fundamental to a number of disciplines, from health sciences to machine learning. However, few, if any, studies exist that have assessed optimal sampling strategies for in situ self-reports. In addition, few technologies exist that facilitate benchmarking self-report accuracy for...
Chapter
The development of location systems based on mobile phone technology was originally driven by the U.S. Federal Communication Commission E911 mandate and its European Community counterpart E112 to locate mobile phone calls to assist in the delivery of emergency services. In addition, the wide adoption and ubiquitous connectivity of cellular phones m...
Chapter
Estimating location with 802.11 was first proposed in 2000 by Bahl et al. [8], and since then, many variants have been developed. At their most basic, all of these systems work the same way: 802.11 radios and their supporting drivers allow a device to scan for nearby 802.11 access points (APs). Regardless of the variant of 802.11 (a, b, g, n) or wh...
Article
Accurate indoor localization has long been an objective of the ubiquitous computing research community, and numerous indoor localization solutions based on 802.11, Bluetooth, ultrasound and infrared technologies have been proposed. This paper presents the first accurate GSM indoor localization system that achieves median within floor accuracy of 4...
Conference Paper
Securing interactions between devices that do not know each other a priori is an important and challenging task. We present Amigo, a technique to authenticate co-located devices using knowledge of their shared radio environment as proof of physical proximity. We present eval- uation results that show that our technique is robust against a range of...
Conference Paper
With the proliferation of mobile devices, spontaneous interactions between co-located devices that do not know each other a priori will become commonplace. Securing these interactions against eavesdropping and man-in-the-middle attacks is an important and challenging task. In this paper, we postulate that mobile devices that are positioned in close...
Conference Paper
Full-text available
When a mobile user dials 911, a key to arriving to the emergency scene promptly is knowing the location of the mobile user. This paper presents SkyLoc, a GSM fingerprinting-based localization system that runs on a mo- bile phone and identifies the current floor of a user in tall multi-floor buildings. Knowing the floor in a tall building significan...
Conference Paper
This paper examines the positioning accuracy of a GSM beacon- based location system in a metropolitan environment. We explore five factors effecting positioning accuracy: location algorithm choice, scan set size, simultaneous use of cells from different providers, training and testing on different devices, and calibration data density. We collected...
Conference Paper
Full-text available
Recognition of everyday physical activities is difficult due to the challenges of building informative, yet unobtrusive sensors. The most widely deployed and used mobile computing device today is the mobile phone, which presents an obvious candidate for recognizing activities. This paper explores how coarse-grained GSM data from mobile phones can b...
Conference Paper
Full-text available
Location-based computing (LBC) is becoming increasing important in both industry and academia. A key challenge is the pervasive deployment of LBC technologies; to be effective they must run on a wide variety of client platforms, including laptops, PDAs, and mobile phones, so that location data can be acquired anywhere and accessed by any applicatio...
Conference Paper
Recent research has shown that one can use Distributed Hash Tables (DHTs) to build scalable, robust and efficient applications. One question that is often left unanswered is that of simplicity of implementation and deployment. In this paper, we explore a case study of building an application for which ease of deployment dominated the need for high...
Conference Paper
Location-enhanced mobile devices are becoming common, but applications built for these devices find themselves suering a mis- match between the latitude and longitude that location sensors provide and the colloquial place label that applications need. Conveying my loca- tion to my spouse, for example as (48.13641N, 11.57471E), is less infor- mative...
Conference Paper
Full-text available
We report on a two-week deployment of a peer-to-peer, mobile, location-enhanced messaging service. This study is specifically aimed at investigating the need for and effectiveness of automatic location disclosure mechanisms, the emerging strategies to achieve plausible deniability, and at understanding how place and activity are used to communicate...
Conference Paper
Location systems that are based on scanning for nearby radio sources can estimate the position of a mobile device with reasonable accuracy and high coverage. These systems require a calibration step in which a map is built from radio-readings taken on a location-aware device. War driving, for example, calibrates the positions of WiFi access points...
Conference Paper
Accurate indoor localization has long been an objective of the ubiquitous computing research community, and numerous indoor lo- calization solutions based on 802.11, Bluetooth, ultrasound and infrared technologies have been proposed. This paper presents the first accurate GSM indoor localization system that achieves median accuracy of 5 me- ters in...
Conference Paper
In this paper, we argue that localization solution based on cellular phone technology, specifically GSM phones, is a sufficient and attractive option in terms of coverage and accuracy for a wide range of indoor, outdoor, and place-based location-aware applications. We present preliminary results that indicate that GSM-based localization systems hav...
Article
We are developing a new multiplayer pervasive game, called The Drop, designed to be compelling to play and yet practical to deploy in real-world settings. In The Drop, two teams use mobile phones to play a version of "capture the flag," where one team hides a virtual "briefcase" in a public place and the other team attempts to find it within a spec...
Conference Paper
In this paper, we introduce a compact system for fusing location data with data from simple, low-cost, non-location sensors to infer a user's place and situational context. Specifically, the system senses location with a GSM cell phone and a WiFi-enabled mobile device (each running Place Lab), and collects additional sensor data using a 2" x 1" sen...
Conference Paper
Communication of one's location as part of a social discourse is common practice, and we use a variety of technologies to satisfy this need. This practice suggests a potentially useful capability that technology may sup- port more directly. We present such a social location disclosure service, Reno, designed for use on a common mobile phone platfor...
Conference Paper
Location awareness is an important capability for mobile computing. Yet inexpensive, pervasive positioning—a requirement for wide-scale adoption of location-aware computing—has been elusive. We demonstrate a radio beacon-based approach to location, called Place Lab, that can overcome the lack of ubiquity and high-cost found in existing location sen...
Conference Paper
Advances in location-enhanced technology are making it easier for us to be located by others. These new technologies present a difficult privacy tradeoff, as disclosing one's location to another person or service could be risky, yet valuable. To explore whether and what users are willing to disclose about their location to social relations, we cond...
Article
Full-text available
Location-enhanced applications are poised to become the first real-world example of ubiquitous computing. In this paper, we emphasize the practical aspects of getting location-enhanced applications deployed on existing devices, such as laptops, tablets, PDAs, and cell phones, without the need to purchase additional sensors or install special infras...
Chapter
Full-text available
Place Lab is a system for positioning a user based on passive monitoring of 802.11 access points. Place Lab seeks preserve the user’s privacy by preventing disclosures, even to “trusted” systems in the infrastructure. We are pursing two avenues to explore these and other privacy issues in the domain of socially-oriented applications. We are doing f...
Article
Recent research has convincingly demonstrated that one can build scalable, robust, and efficient distributed hash tables (DHTs). However, most applications built over DHTs either have very simple application requirements, in which case strictly layering them over a generic DHT is straightforward, or use specially modified DHT implementations, which...
Article
We are developing a new multiplayer pervasive game, called The Drop, designed to be compelling to play and yet practical to deploy in real-world settings. In The Drop, two teams use mobile phones to play a version of "capture the flag," where one team hides a virtual "briefcase" in a public place and the other team attempts to find it within a spec...
Conference Paper
Location systems have long been identied as an impor- tant component of emerging mobile applications. Most research on location systems has focused on precise lo- cation in indoor environments. However, many location applications (for example, location-aware web search) become interesting only when the underlying location system is available ubiqui...
Conference Paper
Full-text available
Knowledge of the physical locations of mobile devices such as laptops or PDA's is becoming increasingly important with the rise of location-based services such as specialized web search, navigation, and social network applications; further- more, location information is a key foundation for high-level activity inferencing. In this paper we propose...
Article
Newer technologies are allowing employers to keep tabs on workers as never before. These tactics range from radiofrequency identification (RFID) tags to GPS chips embedded in cellphones and company cars. Even video surveillance is being reborn, with ...
Conference Paper
This paper explores end-user sensor installation for domestic ubiquitous computing applications and proposes five design principles to support this task. End-user sensor installation offers several advantages: it can reduce costs, enhance users' sense of control, accommodate diverse deployment environments, and increase users' acceptance of the tec...
Article
Full-text available
Computer-supported coordinated care uses technology to aid the network of people who support an elder living at home. CSCC supports improved communication among individuals and a balanced distribution of responsibilities to allow the elder to live at home despite increasing care needs. The problem of coordinating the care of elders living at home h...
Conference Paper
Oasis is an asymmetric peer-to-peer data management system tailored to the requirements of pervasive computing. Drawing upon applications from the literature, we motivate three high-level requirements: availability, manageability, and programmability. Oasis addresses these requirements by employing a peer-to-peer network of weighted replicas and pe...
Article
In this paper, we define the space of Computer-Supported Coordinated Care (CSCC), an approach that focuses on using technology to aid the entire community of people who support an elder who lives at home. We conducted interviews with people involved in the care of elders to identify their needs. We subsequently conducted an in-situ evaluation of a...
Article
Full-text available
In this paper, we define the space of Computer-Supported Coordinated Care (CSCC), an approach that focuses on using technology to aid the entire community of people who support an elder who lives at home. We conducted interviews with people involved in the care of elders to identify their needs. We subsequently conducted an in-situ evaluation of a...
Article
In an evolving software system, components must be able to change independently while remaining compatible with their peers. One obstacle to independent evolution is the brittle parameter problem : the ability of two components to communicate can depend on a number of inessential details of the types, structure, and/or contents of the values commun...
Conference Paper
In an evolving software system, components must be able to change independently while remaining compatible with their peers. One obstacle to independent evolution is the parts of the message remain unaffected.We present HydroJ, an extension of Java that addresses this problem. In HydroJ, components communicate using self-describing, semi-structured...
Article
FlashBack is a peer-to-peer backup algorithm designed for powerconstrained devices running in a personal area network (PAN). Backups are performed transparently as local updates initiate the spread of backup data among a subset of the currently available peers. Flashback limits power usage by avoiding flooding and keeping small neighbor sets. Flash...
Conference Paper
This paper presents a decentralized variant of David Gifford's classic weighted-voting scheme for managing replicated data. Weighted voting offers a familiar consistency model and supports on-line replica reconfiguration. These properties make it a good fit for applications in the pervasive computing domain. By distributing versioned metadata along...
Conference Paper
Full-text available
To be widely adopted, location-aware computing must be as effortless, familiar and rewarding as web search tools like Google. We envisage the global scale Place Lab, consisting of an open software base and a community building activity as a way to bootstrap the broad adoption of location-aware computing. The initiative is a laboratory because it wi...
Article
Full-text available
Our challenge to the research community is to make location-enhanced web services valuable and readily accessible to a very large number of people in daily, real world, situations. We envisage a global scale, multi- organization and interdisciplinary initiative, Place Lab, that will bootstrap the broad adoption of the location-enhanced Web. Our res...
Article
This paper describes the software architecture for our pen-based electronic whiteboard system, called Flatland. The design goal of Flatland is to support various activities on personal office whiteboards, while maintaining the outstanding ease of use and informal appearance of conventional whiteboards. The GUI framework of existing window systems i...
Article
A number of recent systems have provided rich facilities for manipulating the timelines of applications. Such timelines represent the history of an application's use in some session, and captures the effects of the user's interactions with that application. Applications can use timeline manipulation techniques prosaically as a way to provide undo a...
Conference Paper
Full-text available
Ubiquitous computing is finally becoming a reality. However, there are many practical issues that stand in the way of mass acceptance. We have been investigating these practical concerns within the context of an autonomous application that takes care of houseplants using a sensor network and a mobile robot. We believe that emphasizing autonomy and...
Article
Ubiquitous computing is finally becoming a reality. However, there are many practical issues that stand in the way of mass acceptance. We have been investigating these practical concerns within the context of an autonomous application that takes care of houseplants using a sensor network and a mobile robot. We believe that emphasizing autonomy and...
Article
Labscape, a ubiquitous computing environment for cell biologists, was implemented twice: once using only standard tools for distributed systems (TCP sockets, and shared file systems) and once using one.world, a runtime system designed specifically to support ubiquitous applications. The application is analyzed in terms of the system properties that...
Conference Paper
Full-text available
While wireless sensor networks offer new capabilities, there are a number of issues that hinder their deployment in practice. We argue that robotics can solve or greatly reduce the impact of many of these issues. Our hypothesis has been tested in the context of an autonomous system to care for houseplants that we have deployed in our office environ...
Conference Paper
Labscape, a ubiquitous computing environment for cell biologists, was implemented twice: once using only standard tools for distributed systems (TCP sockets and shared file systems) and once using one.world, a runtime system designed specifically to support ubiquitous applications. We analyze Labscape in terms of the system properties that are requ...
Article
. This paper describes an experiment to extend the reach of the document-centric metaphors of computing to new physical and virtual objects in the workplace. By bringing these entities into the sphere of electronic documents, we leverage users' knowledge and expectations about how documents work, and also leverage existing tools and applications th...
Article
A number of recent systems have provided rich facilities for manipulating the timelines of applications. Such timelines represent the history of an application's use in some session, and captures the effects of the user's interactions with that application. Applications can use timeline manipulation techniques prosaically as a way to provide undo a...
Article
As cycle times grow relative to memory speeds, the cache performance of algorithms has an increasingly large impact on overall performance. Unfortunately, most commonly used algorithms were not designed with cache performance in mind. This paper investigates the cache performance of implicit heaps. We present optimizations which significantly reduc...
Article
We investigate the effect that caches have on the performance of sorting algorithms both experimentally and analytically. To address the performance problems that high cache miss penalties introduce we restructure mergesort, quicksort, and heapsort in order to improve their cache locality. For all three algorithms the improvement in cache performan...
Article
Full-text available
We designed the Flatland augmented whiteboard interface for informal office work. Our research investigates three different building approaches based on input from user studies
Article
Full-text available
Document properties are a compelling infrastructure on which to develop document management applications. A property-based approach avoids many of the problems of traditional hierarchical storage mechanisms, reflects document organizations meaningful to user tasks, provides a means to integrate the perspectives of multiple individuals and groups, a...
Article
Document properties are a compelling basis for the design of a document management infrastructure. They avoid many of the problems of traditional hierarchical storage mechanisms, reflect higher-level concerns more meaningful to users, provide a means to integrate the perspectives of multiple individuals and groups, and do this all within a uniform...
Article
Flatland is an augmented whiteboard designed to assist informal activities in one's office environment. Current research focus is on the software architecture to support stroke-based interaction. This demonstration illustrates the user interface aspects of the board, focusing on its screen real estate management, flexible control of various behavio...
Article
Flatland is an augmented whiteboard interface designed for informal office work. Our research has investigated approaches to building an augmented whiteboard in the context of continuous, long term office use. In particular, we have pursued three avenues of research based on input from user studies: techniques for the management of space on the boa...
Conference Paper
Full-text available
Caching in the Placeless Documents system poses new challenges because users can attach active properties to documents. Active properties can modify the document's content as seen by a user. Thus, the caching mechanisms must take into account that a document's content not only depends on when the document was last modified, but also on the set of p...
Article
Full-text available
Most document storage takes place through computer file systems, and most interaction with documents is performed in terms of the structure and facilities that those filesystems provide. But documents are not files. Our goal is to provide an infrastructure for managing documents, not files. We propose a uniform mechanism for managing, organising, s...
Conference Paper
Full-text available
Programmable Embodied Agents are portable, wireless, interactivedevices embodying specific, differentiable, interactivecharacteristics. They take the form of identifiable characters whoreside in the physical world and interact directly with users. Theycan act as an out-of-band communication channel between users, asproxies for system components or...
Article
This paper describes a model for studying the cache performance of algorithms in a direct-mapped cache. Using this model, we analyze the cache performance of several commonly occurring memory access patterns: (i) sequential and random memory traversals, (ii) systems of random accesses, and (iii) combinations of each. For each of these, we give exac...
Article
We present and analyze the performance of two newcounting protocols. Counting protocols use bounded headers yet provide a reliable FIFO channel in a computer network in which packets may be lost or delivered out of order. Using the classic alternating bit protocol as a basis, we derive two counting protocols: (i) theone-bit protocolwhich uses one b...
Article
We investigate the effect that caches have on the performance of sorting algorithms both experimentally and analytically. To address the performance problems that high cache miss penalties introduce we restructure mergesort, quicksort, and heapsort in order to improve their cache locality. For all three algorithms the improvement in cache performan...
Conference Paper
The calendar queue is an important implementation of a priority queue which is particularly useful in discrete event simulators. In this paper we present an analysis of the static calendar queue which maintains N active events. A step of the discrete event simulator removes and processes the event with the smallest associated time and inserts a new...
Conference Paper
In this paper, we investigate the practical perfor- mance of lock-free techniques that provide synchro- nization on shared-memory multiprocessors. Our goal is to provide a technique to allow designers of new protocols to quickly determine an algorithm' s performance characteristics. We develop a simple analytical performance model based on the arch...
Article
We introduce a generalization of the counting networks of Aspnes, Herlihy, and Shavit [AHS91]. Our counting networks are constructed using k-balancers, rather than the 2-balancers of Aspnes et al. For reasonable values of k, k-balancers and 2-balancers can be implemented with equal efficiency on existing computers. Our k-bitonic networks have depth...
Article
Full-text available
: There are two aspects to technical support for collaborative activity; support for content work and support for coordination. The design of CSCW systems must typically address both of these, combining them in a collaborative application. This approach, however, suffers from a variety of well-known problems, not least the compatibility between col...
Article
We introduce and evaluate the performance of several new protocols from a new class of pro-tocols, called counting protocols. Counting protocols provide a reliable FIFO channel in computer networks in which packets may be lost or delivered out of order. Three counting protocols are presented: (i) the one-bit protocol which uses one bit header and s...