Publications

FXPAL publishes in top scientific conferences and journals.

2012
Publication Details
  • ACM Multimedia 2012
  • Oct 29, 2012

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Faithful sharing of screen contents is an important collaboration feature. Prior systems were designed to operate over constrained networks. They performed poorly even without such bottlenecks. To build a high performance screen sharing system, we empirically analyzed screen contents for a variety of scenarios. We showed that screen updates were sporadic with long periods of inactivity. When active, screens were updated at far higher rates than was supported by earlier systems. The mismatch was pronounced for interactive scenarios. Even during active screen updates, the number of updated pixels were frequently small. We showed that crucial information can be lost if individual updates were merged. When the available system resources could not support high capture rates, we showed ways in which updates can be effectively collapsed. We showed that Zlib lossless compression performed poorly for screen updates. By analyzing the screen pixels, we developed a practical transformation that significantly improved compression rates. Our system captured 240 updates per second while only using 4.6 Mbps for interactive scenarios. Still, while playing movies in fullscreen mode, our approach could not achieve higher capture rates than prior systems; the CPU remains the bottleneck. A system that incorporates our findings is deployed within the lab.
Publication Details
  • ACM Multimedia '12
  • Oct 29, 2012

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DisplayCast is a many to many screen sharing system that is targeted towards Intranet scenarios. The capture software runs on all computers whose screens need to be shared. It uses an application agnostic screen capture mechanism that creates a sequence of pixmap images of the screen updates. It transforms these pixmaps to vastly improve the lossless Zlib compression performance. These algorithms were developed after an extensive analysis of typical screen contents. DisplayCast shares the processor and network resources required for screen capture, compression and transmission with host applications whose output needs to be shared. It balances the need for high performance screen capture with reducing its resource interference with user applications. DisplayCast uses Zeroconf for naming and asynchronous location. It provides support for Cisco WiFi and Bluetooth based localization. It also includes a HTTP/REST based controller for remote session initiation and control. DisplayCast supports screen capture and playback in computers running Windows 7 and Mac OS X operating systems. Remote screens can be archived into a H.264 encoded movie on a Mac. They can also be played back in real time on Apple iPhones and iPads. The software is released under a New BSD license.
Publication Details
  • CIKM 2012 Books Online Workshop Keynote Address
  • Oct 29, 2012

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Reading is part of how we understand the world, how we share knowledge, how we play, and even how we think. Although reading text is the dominant form of reading, most of the text we read— letters, numbers, words, and sentences—is surrounded by illustrations, photographs, and other kinds of symbols that we include as we read. As dynamic displays migrate into the real world at many scales, whether personal devices, handhelds, or large screens in both interior and exterior spaces, opportunities for reading migrate as well. As has happened continually throughout the history of reading, new technologies, physical forms and social patterns create new genres, which themselves may then combine or collide to morph into something new. At PARC, the RED (Research in Experimental Design) group examined emerging technologies for impact on media and the human relationship to information, especially reading. We explored new ways of experiencing text: new genres, new styles of interaction, and unusual media. Among the questions we considered: how might “the book” change? More particularly, how does the experience of reading change with the introduction of new technologies…and how does it remain the same? In this talk, we'll discuss the ideas behind the design and research process that led to creating eleven different experiences of new forms of reading. We’ll also consider how our technological context for reading has changed in recent years, and what influence the lessons from XFR may have on our ever-developing online reading experiences.

Through the Looking-Glass: Mirror Worlds for Augmented Awareness & Capability

Publication Details
  • ACM MM 2012
  • Oct 29, 2012

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We describe a system for supporting mirror worlds - 3D virtual models of physical spaces that reflect the structure and activities of those spaces to help support context awareness and tasks such as planning and recollection of events. Through views on web pages, portable devices, or on 'magic window' displays located in the physical space, remote people may 'look in' to the space, while people within the space are provided information not apparent through unaided perception. For example, by looking at a mirror display, people can learn how long others have been present, or where they have been. People in one part of a building can get a sense of activities in the rest of the building, know who is present in their office, and look in to presentations in other rooms. The system can be used to bridge across sites and help provide different parts of an organization with a shared awareness of each other's space and activities. We describe deployments of our mirror world system at several locations.
Publication Details
  • Mobile HCI 2012 demo track
  • Sep 21, 2012

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In this demonstration we will show a mobile remote control and monitoring application for a recipe development laboratory at a local chocolate production company. In collaboration with TCHO, a chocolate maker in San Francisco, we built a mobile Web app designed to allow chocolate makers to control their laboratory's machines. Sensor data is imported into the app from each machine in the lab. The mobile Web app is used for control, monitoring, and collaboration. We have tested and deployed this system at the real-world factory and it is now in daily use. This project is designed as part of a research exploration into enhanced collaboration in industrial settings between physically remote people and places, e.g. factories in China with clients in the US.
Publication Details
  • Workshop on Social Mobile Video and Panoramic Video
  • Sep 20, 2012

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The ways in which we come to know and share what we know with others are deeply entwined with the technologies that enable us to capture and share information. As face-to-face communication has been supplemented with ever-richer media––textual books, illustrations and photographs, audio, film and video, and more––the possibilities for knowledge transfer have only expanded. One of the latest trends to emerge amidst the growth of Internet sharing and pervasive mobile devices is the mass creation of online instructional videos. We are interested in exploring how smart phones shape this sort of mobile, rich media documentation and sharing.
Publication Details
  • USENIX/ACM/IFIP Middleware
  • Sep 19, 2012

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Faunus addresses the challenge of specifying and managing complex collaboration sessions. Many entities from various administrative domains orchestrate such sessions. Faunus decouples the entities that specify the session from entities that activate and manage them. It restricts the operations to specific agents using capabilities. It unifies the specification and management operations through its naming system. Each Faunus name is persistent and globally unique. A collection of attributes are attached to each name. Together, they represent a collection of services that form a collaboration session. Anyone can create a name; the creator has full read and write privileges that can be delegated to others. With the proper capability, anyone can modify session attributes between an active and inactive state. Though the system is designed for Internet scale deployments, the security model for providing and revoking capabilities currently assumes an Intranet style deployment. We have incorporated Faunus into a DisplayCast system that originally used Zeroconf. We are incorporating Faunus into another project that will fully exercise the power of Faunus.
Publication Details
  • International Journal on Document Analysis and Recognition (IJDAR): Volume 15, Issue 3 (2012), pp. 167-182.
  • Sep 1, 2012

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When searching or browsing documents, the genre of a document is an important consideration that complements topical characterization. We examine design considerations for automatic tagging of office document pages with genre membership. These include selecting features that characterize genre-related information in office documents, examining the utility of text-based features and image-based features, and proposing a simple ensemble method to improve genre identification performance. In the open-set identification of four office document genres, our experiments show that when combined with image-based features, text-based features do not significantly influence performance. These results provide support for a topic-independent approach to genre identification of office documents. Experiments also show that our simple ensemble method significantly improves performance relative to using a support vector machine (SVM) classifier alone. We demonstrate the utility of our approach by integrating our automatic genre tags in a faceted search and browsing application for office document collections.
Publication Details
  • IIiX 2012
  • Aug 21, 2012

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Exploratory search activities tend to span multiple sessions and involve finding, analyzing and evaluating information and collab-orating with others. Typical search systems, on the other hand, are designed to support a single searcher, precision-oriented search tasks. We describe a search interface and system design of a multi-session exploratory search system, discuss design challenges en-countered, and chronicle the evolution of our design. Our design describes novel displays for visualizing retrieval history infor-mation, and introduces ambient displays and persuasive elements to interactive information retrieval.
Publication Details
  • DIS (Designing Interactive Systems) 2012 Demos track
  • Jun 11, 2012

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We will demonstrate successive and final stages in the iterative design of a complex mixed reality system in a real-world factory setting. In collaboration with TCHO, a chocolate maker in San Francisco, we built a virtual “mirror” world of a real-world chocolate factory and its processes. Sensor data is imported into the multi-user 3D environment from hundreds of sensors and a number of cameras on the factory floor. The resulting virtual factory is used for simulation, visualization, and collaboration, using a set of interlinked, real-time layers of information. It can be a stand-alone or a web-based application, and also works on iOS and Android cell phones and tablet computers. A unique aspect of our system is that it is designed to enable the incorporation of lightweight social media-style interactions with co-workers along with factory data. Through this mixture of mobile, social, mixed and virtual technologies, we hope to create systems for enhanced collaboration in industrial settings between physically remote people and places, such as factories in China with managers in the US.
Publication Details
  • CHI 2012
  • May 7, 2012

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Affect influences workplace collaboration and thereby impacts a workplace's productivity. Participants in face-toface interactions have many cues to each other's affect, but work is increasingly carried out via computer-mediated channels that lack many of these cues. Current presence systems enable users to estimate the availability of other users, but not their affect states or communication preferences. This work investigates relationships between affect state and communication preferences and demonstrates the feasibility of estimating affect state and communication preferences from a presence state stream.
Publication Details
  • CHI 2012
  • May 5, 2012

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Abstract: Pico projectors have lately been investigated as mobile display and interaction devices. We propose to use them as ‘light beams’: Everyday objects sojourning in a beam are turned into dedicated projection surfaces and tangible interaction devices. While this has been explored for large projectors, the affordances of pico projectors are fundamentally different: they have a very small and strictly limited projection ray and can be carried around in a nomadic way during the day. Thus it is unclear how this could be actually leveraged for tangible interaction with physical, real world objects. We have investigated this in an exploratory field study and contribute the results. Based upon these, we present exemplary interaction techniques and early user feedback.

Designing a tool for exploratory information seeking

Publication Details
  • CHI 2012
  • May 5, 2012

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In this paper we describe our on-going design process in building a search system designed to support people's multi-session exploratory search tasks. The system, called Querium, allows people to run queries and to examine results as do conventional search engines, but it also integrates a sophisticated search history that helps people make sense of their search activity over time. Information seeking is a cognitively demanding process that can benefit from many kinds of information, if that information is presented appropriately. Our design process has been focusing on creating displays that facilitate on-going sense-making while keeping the interaction efficient, fluid, and enjoyable.

Querium: A Session-Based Collaborative Search System

Publication Details
  • European Conference on Information Retrieval 2012
  • Apr 1, 2012

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People's information-seeking can span multiple sessions, and can be collaborative in nature. Existing commercial offerings do not effectively support searchers to share, save, collaborate or revisit their information. In this demo paper we present Querium: a novel session-based collaborative search system that lets users search, share, resume and collaborate with other users. Querium provides a number of novel search features in a collaborative setting, including relevance feedback, query fusion, faceted search, and search histories
Publication Details
  • DAS 2012
  • Mar 27, 2012

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This paper describes a system for capturing images of a book with a 3D stereo camera which performs dewarping to produce output images that are flattened. A Fujifilm consumer grade 3D camera (FinePix W3) provides a highly mobile and low cost 3D capture device. Applying standard computer vision algorithms, the camera is calibrated and the captured images are stereo rectified. Due to technical limitations, the resulting point cloud has defects such as splotches and noise, which make it hard to recover the precise 3D locations of the points on the book pages. We address this problem by computing curve profiles of the depth map and using them to build a cylinder model of the pages. We then generate a mesh M1 on the source image and project this into a mesh M2 on the cylinder model in virtual space. Finally, the mesh M2 is flattened and the pixels in M1 are interpolated and rendered via M2 onto the output image. We have implemented a prototype of the system and report on some preliminary evaluation results.
Publication Details
  • ACM Transactions on Computer Human Interaction
  • Mar 1, 2012

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To combine the affordances of paper and computers, prior research has proposed numerous interactive paper systems that link specific paper document content to digital operations such as multimedia playback and proofreading. Yet, it remains unclear to what degree these systems bridge the inherent gap between paper and computers when compared to existing paper-only and computer-only interfaces. In particular, given the special properties of paper, such as limited dynamic feedback, how well does an average new user learn to master the interactive paper system? What factors affect the user performance? And how does the paper interface work in a typical use scenario? To answer these questions, we conducted two empirical experiments on a generic pen gesture based command system, called PapierCraft [Liao, et al., 2008], for paper-based interfaces. With it, people can select sections of printed document and issue commands such as copy and paste, linking and in-text search. The first experiment focused on the user performance of drawing pen gestures on paper. It proves that users can learn the command system in about 30 minutes and achieve a performance comparable to a Table PC-based interface supporting the same gestures. The second experiment examined the application of the command system in Active Reading tasks. The results show promise for seamless integration of paper and computers in Active Reading for their combined affordances. In addition, our study identifies some key design issues, such as the pen form factor and feedback of gestures. This paper contributes to better understanding on pros and cons of paper and computers, and sheds light on the design of future interfaces for document interaction.

TalkMiner: A Lecture Video Search Engine

Publication Details
  • Fuji Xerox Technical Report, No. 21, 2012, pp. 118-128
  • Feb 3, 2012

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The design and implementation of a search engine for lecture webcasts is described. A searchable text index is created allowing users to locate material within lecture videos found on a variety of websites such as YouTube and Berkeley webcasts. The searchable index is built from the text of presentation slides appearing in the video along with other associated metadata such as the title and abstract when available. The automatic identification of distinct slides within the video stream presents several challenges. For example, picture-in-picture compositing of a speaker and a presentation slide, switching cameras, and slide builds confuse basic algorithms for extracting keyframe slide images. Enhanced algorithms are described that improve slide identification. A public system was deployed to test the algorithms and the utility of the search engine at www.talkminer.com. To date, over 17,000 lecture videos have been indexed from a variety of public sources.
Publication Details
  • Fuji Xerox Technical Report No.21 2012
  • Feb 2, 2012

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Modern office work practices increasingly breach traditional boundaries of time and place, making it difficult to interact with colleagues. To address these problems, we developed myUnity, a software and sensor platform that enables rich workplace awareness and coordination. myUnity is an integrated platform that collects information from a set of independent sensors and external data aggregators to report user location, availability, tasks, and communication channels. myUnity's sensing architecture is component-based, allowing channels of awareness information to be added, updated, or removed at any time. Multiple channels of input are combined and composited into a single, high-level presence state. Early studies of a myUnity deployment have demonstrated that the platform allows quick access to core awareness information and show that it has become a useful tool for supporting communication and collaboration in the modern workplace.
Publication Details
  • Personal and Ubiquitous Computing (PUC)
  • Feb 1, 2012

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Presence systems are valuable in supporting workplace communication and collaboration. These systems are only effective if widely adopted and used. User perceptions of the utility of the information being shared and their comfort sharing such information strongly impact adoption and use. This paper describes the results of a survey of user preferences regarding comfort with and utility of workplace presence systems; the effects of sampling frequency, fidelity, and aggregation; and design implications of these results. We present new results that extend some past findings while challenging others. We contribute new design insights that inform the design of presence technologies to increase both utility and adoption.
2011
Publication Details
  • The 10th International Conference on Virtual Reality Continuum and Its Applications in Industry
  • Dec 11, 2011

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Augmented Paper (AP) is an important area of Augmented Reality (AR). Many AP systems rely on visual features for paper doc-ument identification. Although promising, these systems can hardly support large sets of documents (i.e. one million documents) because of the high memory and time cost in handling high-dimensional features. On the other hand, general large-scale image identification techniques are not well customized to AP, costing unnecessarily more resource to achieve the identification accuracy required by AP. To address this mismatching between AP and image identification techniques, we propose a novel large-scale image identification technique well geared to AP. At its core is a geometric verification scheme based on Minimum visual-word Correspondence Set (MICSs). MICS is a set of visual word (i.e. quantized visual fea-ture) correspondences, each of which contains a minimum number of correspondences that are sufficient for deriving a transformation hypothesis between a captured document image and an indexed image. Our method selects appropriate MICSs to vote in a Hough space of transformation parameters, and uses a robust dense region detection algorithm to locate the possible transformation models in the space. The models are then utilized to verify all the visual word correspondence to precisely identify the matching indexed image. By taking advantage of unique geometric constraints in AP, our method can significantly reduce the time and memory cost while achieving high accuracy. As showed in evaluation with two AP systems called FACT and EMM, over a dataset with 1M+ images, our method achieves 100% identification accuracy and 0.67% registration error for FACT; For EMM, our method outperforms the state-of-the-art image identification approach by achieving 4% improvements in detection rate and almost perfect precision, while saving 40% and 70% memory and time cost.

PaperUI

Publication Details
  • Springer LNCS
  • Dec 1, 2011

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PaperUI is a human-information interface concept that advocates using paper as displays and using mobile devices, such as camera phones or camera pens, as traditional computer-mice. When emphasizing technical efforts, some researchers like to refer the PaperUI related underlying work as interactive paper system. We prefer the term PaperUI for emphasizing the final goal, narrowing the discussion focus, and avoiding terminology confusion between interactive paper system and interactive paper computer [40]. PaperUI combines the merits of paper and the mobile devices, in that users can comfortably read and flexibly arrange document content on paper, and access digital functions related to the document via the mobile computing devices. This concept aims at novel interface technology to seamlessly bridge the gap between paper and computers for better user experience in handling documents. Compared with traditional laptops and tablet PCs, devices involved in the PaperUI concept are more light-weight, compact, energy efficient, and widely adopted. Therefore, we believe this interface vision can make computation more convenient to access for general public.
Publication Details
  • ACM Multimedia 2011
  • Nov 28, 2011

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This paper describes methods for clustering photos that include both time stamps and location coordinates. We present versions of a two part method that first detects clusters using time and location information independently. These candidate clusters partition the set of time-ordered photos. A subset of the candidate clusters is selected by an efficient dynamic programming procedure to optimize a cost function. We propose several cost functions to design clusterings that are coherent in space, time, or both. One set of cost functions minimizes inter-photo distances directly. A second set maximizes an information measure to select clusterings for consistency in both time and space across scale.
Publication Details
  • ACM Multimedia 2011
  • Nov 28, 2011

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Embedded Media Markers (EMMs) are nearly transparent icons printed on paper documents that link to associated digital media. By using the document content for retrieval, EMMs are less visually intrusive than barcodes and other glyphs while still providing an indication for the presence of links. An initial implementation demonstrated good overall performance but exposed difficulties in guaranteeing the creation of unambiguous EMMs. We developed an EMM authoring tool that supports the interactive authoring of EMMs via visualizations that show the user which areas on a page may cause recognition errors and automatic feedback that moves the authored EMM away from those areas. The authoring tool and the techniques it relies on have been applied to corpora with different visual characteristics to explore the generality of our approach.
Publication Details
  • ACM Multimedia Industrial Exhibit
  • Nov 28, 2011

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The Active Reading Application (ARA) brings the familiar experience of writing on paper to the tablet. The application augments paper-based practices with audio, the ability to review annotations, and sharing. It is designed to make it easier to review, annotate, and comment on documents by individuals and groups. ARA incorporates several patented technologies and draws on several years of research and experimentation.
Publication Details
  • ACM Multimedia Industrial Exhibits
  • Nov 28, 2011

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Modern office work practices increasingly breach traditional boundaries of time and place, making it difficult to interact with colleagues. To address these problems, we developed myUnity, a software and sensor platform that enables rich workplace awareness and coordination. myUnity is an integrated platform that collects information from a set of independent sensors and external data aggregators to report user location, availability, tasks, and communication channels. myUnity's sensing architecture is component-based, allowing channels of awareness information to be added, updated, or removed at any time. Our current system includes a variety of sensor and data input, including camera-based activity classification, wireless location trilateration, and network activity monitoring. These and other input channels are combined and composited into a single, high-level presence state. Early studies of a myUnity deployment have demonstrated that use of the platform allows quick access to core awareness information and show it has become a useful tool supporting communication and collaboration in the modern workplace.

Session-based search with Querium

Publication Details
  • HCIR 2011
  • Oct 20, 2011

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We illustrate the use of Querium, a novel search system designed to support people's collaborative and multi-session search tasks, in the context of the HCIR 2011 Search Challenge. This report demonstrates how a Querium's interface and search engine can be used to search for documents in an open-ended, exploratory task. We illustrate the use of relevance feedback, faceted search, query fusion, and the search history, as well as commenting and overview functions.

Designing for Collaboration in Information Seeking

Publication Details
  • HCIR 2011
  • Oct 19, 2011

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Information seeking is often a collaborative activity that can take can take many forms; in this paper we focus on explicit, intentional collaboration of small and explore a range of design decisions that should be considered when building Human-Computer Information Retrieval (HCIR) tools that support collaboration. In particular, we are interested in exploring the interplay between algorithmic mediation of collaboration and the mediated communication among team members. We argue that certain characteristics of the group's information need call for different design decisions.
Publication Details
  • Oct 3, 2011

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Documents created, stored, and retrieved digitally are often printed on paper to be read for the purposes of producing new documents. The cycle of electronic document "consumption" and production is often broken in the middle by printing. Our research in XLibris has examined these transitions between the digital and paper worlds. Starting with interfaces for analytic reading, we have focused on annotation, on retrieval and re-retrieval, and on shared annotation. In this talk, I will describe the interfaces and the empirical evaluations we have conducted, and will discuss the potential of this technology in digital--and in physical--libraries.

PaperUI

Publication Details
  • CBDAR 2011
  • Sep 18, 2011

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PaperUI is a human-computer interface concept that treats paper as displays that users can interact with via mobile devices such as mobile phones and projectors. It combines the merits of paper and the mobile devices. Compared with traditional laptops and tablet PCs, devices involved in this concept are more light-weight, compact, energy efficient, and widely adopted. Therefore, we believe this interface vision can make computation more convenient to access for general public. With our implemented prototype, pilot users can read documents easily and comfortably on paper, and access many digital functions related to the document via a camera phone or a mobile projector Invited Talk. http://imlab.jp/cbdar2011/#keynote

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This demo shows an interactive paper system called MixPad, which features using mice and keyboards to enhance the conventional pen-finger-gesture based interaction with paper documents. Similar to many interactive paper systems, MixPad adopts a mobile camera-projector unit to recognize paper documents, detect pen and finger gestures and provide visual feedback. Unlike these systems, MixPad allows using mice and keyboards to help users interact with fine-grained document content on paper (e.g. individual words and user-defined arbitrary regions), and to facilitate cross-media operations. For instance, to copy a document segment from paper to a laptop, one first points a finger of her non-dominant hand to the segment roughly, and then uses a mouse in her dominant hand to refine the selection and drag it to the laptop; she can also type text as a detailed comment on a paper document. This novel interaction paradigm combines the advantages of mice, keyboards, pens and fingers, and therefore enables rich digital functions on paper.
Publication Details
  • MobileHCI
  • Aug 30, 2011

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Modern office work practices increasingly breach traditional boundaries of time and place, increasing breakdowns workers encounter when coordinating interaction with colleagues. We conducted interviews with 12 workers and identified key problems introduced by these practices. To address these problems we developed myUnity, a fully functional platform enabling rich workplace awareness and coordination. myUnity is one of the first integrated platforms to span mobile and desktop environments, both in terms of access and sensing. It uses multiple sources to report user location, availability, tasks, and communication channels. A pilot field study of myUnity demonstrated the significant value of pervasive access to workplace awareness and communication facilities, as well as positive behavioral change in day-to-day communication practices for most users. We present resulting insights about the utility of awareness technology in flexible work environments.
Publication Details
  • International Journal of Arts and Technology
  • Jul 25, 2011

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Mobile media applications need to balance user and group goals, attentional constraints, and limited screen real estate. In this paper, we describe the iterative development and testing of an application that explores these tradeo ffs. We developed early prototypes of a retrospective, time-based system as well as a prospective and space-based system. Our experiences with the prototypes led us to focus on the prospective system. We argue that attentional demands dominate and mobile media applications should be lightweight and hands-free as much as possible.

Estimation Methods for Ranking Recent Information

Publication Details
  • SIGIR2011
  • Jul 24, 2011

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Temporal aspects of documents can impact relevance for certain kinds of queries. In this paper, we build on earlier work of modeling temporal information. We propose an extension to the Query Likelihood Model that incorporates query-specific information to estimate rate parameters, and we introduce a temporal factor into language model smoothing and query expansion using pseudo-relevance feedback. We evaluate these extensions using a Twitter corpus and two newspaper article collections. Results suggest that, compared to prior approaches, our models are more effective at capturing the temporal variability of relevance associated with some topics.

Secured histories for presence systems

Publication Details
  • SECOTS 2011
  • May 23, 2011

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As sensors become ever more prevalent, more and more information will be collected about each of us. A longterm research question is how best to support beneficial uses while preserving individual privacy. Presence systems are an emerging class of applications that support collaboration. These systems leverage pervasive sensors to estimate end-user location, activities, and available communication channels. Because such presence data are sensitive, to achieve wide-spread adoption, sharing models must reflect the privacy and sharing preferences of the users. To reflect users' collaborative relationships and sharing desires, we introduce CollaPSE security in which an individual has full access to her own data, a third party processes the data without learning anything about the data values, and users higher up in the hierarchy learn only statistical information about the employees under them. We describe simple schemes that efficiently realize CollaPSE security for time series data. We implemented these protocols using readily available cryptographic functions, and integrated the protocols with FXPAL's MyUnity presence system.
Publication Details
  • CHI 2011 Workshop on Mobile and Personal Projection (MP2)
  • May 8, 2011

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The field of personal mobile projection is advancing quickly and a variety of work focuses on enhancing physical objects in the real world with dynamically projected digital artifacts. Due to technological restrictions, none of them has yet investigated, what we feel is the most promising research direction: the (bi-manual) interaction with mobile projections on non-planar surfaces. To elicit the challenges of this field of research, we contribute (1) a technology-centered design space for mobile projector-based interfaces and discus related work in light thereof, (2) a discussion on lessons learnt from two of our research projects, which aim at improving both usability and user experience and (3) an outline of open research challenges within this field.
Publication Details
  • CHI 2011
  • May 7, 2011

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For document visualization, folding techniques provide a focus-plus-context approach with fairly high legibility on flat sections. To enable richer interaction, we explore the design space of multi-touch document folding. We discuss several design considerations for simple modeless gesturing and compatibility with standard Drag and Pinch gestures, and categorize gesture models along the characteristics of Symmetric/Asymmetric and Sequential/Parallel, which yields three gesture models. We built a prototype document workspace application that integrates folding and standard gestures, and a prototype for experimenting with the gesture models. A user study was conducted to compare the three models and to analyze the factors of fold direction, target symmetry, and target tolerance in user performance of folding a document to a specific shape. Our results indicate that all three factors were significant for task times, and parallelism was greater for symmetric targets.
Publication Details
  • CHI 2011 workshop on Video interaction - Making broadcasting a successful social media
  • May 7, 2011

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A variety of applications are emerging to support streaming video from mobile devices. However, many tasks can benefit from streaming specific content rather than the full video feed which may include irrelevant, private, or distracting content. We describe a system that allows users to capture and stream targeted video content captured with a mobile device. The application incorporates a variety of automatic and interactive techniques to identify and segment desired content, allowing the user to publish a more focused video stream.
Publication Details
  • ACM International Conference on Multimedia Retrieval (ICMR)
  • Apr 17, 2011

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User-generated video from mobile phones, digital cameras, and other devices is increasing, yet people rarely want to watch all the captured video. More commonly, users want a single still image for printing or a short clip from the video for creating a panorama or for sharing. Our interface aims to help users search through video for these images or clips in a more efficient fashion than fast-forwarding or "scrubbing" through a video by dragging through locations on a slider. It is based on a hierarchical structure of keyframes in the video, and combines a novel user interface design for browsing a video segment tree with new algorithms for keyframe selection, segment identification, and clustering. These algorithms take into account the need for quality keyframes and balance the desire for short navigation paths and similarity-based clusters. Our user interface presents keyframe hierarchies and displays visual cues for keeping the user oriented while browsing the video. The system adapts to the task by using a non-temporal clustering algorithm when a the user wants a single image. When the user wants a video clip, the system selects one of two temporal clustering algorithm based on a measure of the repetitiveness of the video. User feedback provided us with valuable suggestions for improvements to our system.
Publication Details
  • ACM International Conference on Multimedia Retrieval (ICMR) 2011
  • Apr 17, 2011

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Embedded Media Marker (EMM) identification system allows users to retrieve relevant dynamic media associated with a static paper document via camera phones. The user supplies a query image by capturing an EMM-signified patch of a paper document through a camera phone; the system recognizes the query and in turn retrieves and plays the corresponding media on the phone. Accurate image matching is crucial for positive user experience in this application. To address the challenges posed by large datasets and variations in camera-phone-captured query images, we introduce a novel image matching scheme based on geometrically consistent correspondences. Two matching constraints - "injection" and "approximate global geometric consistency" (AGGC), which are unique in EMM identification, are presented. A hierarchical scheme, combined with two constraining functions, is designed to detect the "injective-AGGC" correspondences between images. A spatial neighborhood search approach is further proposed to address challenging cases with large translational shift. Experimental results on a 100k+ dataset show that our solution achieves high accuracy with low memory and time complexity and outperforms the standard bag-of-words approach.

Quantum Computing: A Gentle Introduction

Publication Details
  • MIT Press
  • Mar 18, 2011

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The combination of two of the twentieth century's most influential and revolutionary scientific theories, information theory and quantum mechanics, gave rise to a radically new view of computing and information. Quantum information processing explores the implications of using quantum mechanics instead of classical mechanics to model information and its processing. Quantum computing is not about changing the physical substrate on which computation is done from classical to quantum but about changing the notion of computation itself, at the most basic level. The fundamental unit of computation is no longer the bit but the quantum bit or qubit. This comprehensive introduction to the field offers a thorough exposition of quantum computing and the underlying concepts of quantum physics, explaining all the relevant mathematics and offering numerous examples. With its careful development of concepts and thorough explanations, the book makes quantum computing accessible to students and professionals in mathematics, computer science, and engineering. A reader with no prior knowledge of quantum physics (but with sufficient knowledge of linear algebra) will be able to gain a fluent understanding by working through the book. The text covers the basic building blocks of quantum information processing, quantum bits and quantum gates, showing their relationship to the key quantum concepts of quantum measurement, quantum state transformation, and entanglement between quantum subsystems; it treats quantum algorithms, discussing notions of complexity and describing a number of simple algorithms as well as the most significant algorithms to date; and it explores entanglement and robust quantum computation, investigating such topics as quantifying entanglement, decoherence, quantum error correction, and fault tolerance.

Augmented Perception through Mirror Worlds

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  • Augmented Human 2011
  • Mar 12, 2011

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We describe a system that mirrors a public physical space into cyberspace to provide people with augmented awareness of that space. Through views on web pages, portable devices, or on `Magic Window' displays located in the physical space, remote people may `look in' to the space, while people within the space are provided information not apparent through unaided perception. For example, by looking at a mirror display, people can learn how long others have been present, where they have been, etc. People in one part of a building can get a sense of the activities in the rest of the building, who is present in their office, look in to a talk in another room, etc. We describe a prototype for such a system developed in our research lab and office space.

DiG: A task-based approach to product search

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  • IUI 2011
  • Feb 13, 2011

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While there are many commercial systems designed to help people browse and compare products, these interfaces are typically product centric. To help users more efficiently identify products that match their needs, we instead focus on building a task centric interface and system. With this approach, users initially answer questions about the types of situations in which they expect to use the product. The interface reveals the types of products that match their needs and exposes high-level product features related to the kinds of tasks in which they have expressed an interest. As users explore the interface, they can reveal how those high-level features are linked to actual product data, including customer reviews and product specifications. We developed semi-automatic methods to extract the high-level features used by the system from online product data. These methods identify and group product features, mine and summarize opinions about those features, and identify product uses. User studies verified our focus on high-level features for browsing and low-level features and specifications for comparison.  

Privacy-Preserving Aggregation of Time-Series Data

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  • NDSS 2011
  • Feb 6, 2011

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We consider how an untrusted data aggregator can learn desired statistics over multiple participants' data, without compromising each individual's privacy. We propose a construction that allows a group of participants to periodically upload encrypted values to a data aggregator, such that the aggregator is able to compute the sum of all participants' values in every time period, but is unable to learn anything else. We achieve strong privacy guarantees using two main techniques. First, we show how to utilize applied cryptographic techniques to allow the aggregator to decrypt the sum from multiple ciphertexts encrypted under different user keys. Second, we describe a distributed data randomization procedure that guarantees the differential privacy of the outcome statistic, even when a subset of participants might be compromised.
Publication Details
  • IS&T and SPIE International Conference on Multimedia Content Access: Algorithms and Systems
  • Jan 23, 2011

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This paper describes research activities at FX Palo Alto Laboratory (FXPAL) in the area of multimedia browsing, search, and retrieval. We first consider interfaces for organization and management of personal photo collections. We then survey our work on interactive video search and retrieval. Throughout we discuss the evolution of both the research challenges in these areas and our proposed solutions.
Publication Details
  • Fuji Xerox Technical Report
  • Jan 1, 2011

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Embedded Media Markers, or simply EMMs, are nearly transparent iconic marks printed on paper documents that signify the existence of media associated with that part of the document. EMMs also guide users' camera operations for media retrieval. Users take a picture of an EMM-signified document patch using a cell phone, and the media associated with the EMM-signified document location is displayed on the phone. Unlike bar codes, EMMs are nearly transparent and thus do not interfere with the document appearance. Retrieval of media associated with an EMM is based on image local features of the captured EMM-signified document patch. This paper describes a technique for semi-automatically placing an EMM at a location in a document, in such a way that it encompasses sufficient identification features with minimal disturbance to the original document.
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  • Encyclopledia of the Sciences of Learning
  • Jan 1, 2011

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Supervised Learning is a machine learning paradigm for acquiring the input-output relationship information of a system based on a given set of paired input-output training samples. As the output is regarded as the label of the input data or the supervision, an input-output training sample is also called labelled training data, or supervised data. Occasionally, it is also referred to as Learning with a Teacher (Haykin 1998), Learning from Labelled Data, or Inductive Machine Learning (Kotsiantis, 2007). The goal of supervised learning is to build an artificial system that can learn the mapping between the input and the output, and can predict the output of the system given new inputs. If the output takes a finite set of discrete values that indicate the class labels of the input, the learned mapping leads to the classification of the input data. If the output takes continuous values, it leads to a regression of the input. The input-output relationship information is frequently represented with learning-model parameters. When these parameters are not directly available from training samples, a learning system needs to go through an estimation process to obtain these parameters. Different form Unsupervised Learning, the training data for Supervised Learning need supervised or labelled information, while the training data for unsupervised learning are unsupervised as they are not labelled (i.e., merely the inputs). If an algorithm uses both supervised and unsupervised training data, it is called a Semi-supervised Learning algorithm. If an algorithm actively queries a user/teacher for labels in the training process, the iterative supervised learning is called Active Learning.
2010
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  • ACM International Conference on Multimodal Interfaces
  • Nov 8, 2010

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Embedded Media Barcode Links, or simply EMBLs, are optimally blended iconic barcode marks, printed on paper documents, that signify the existence of multimedia associated with that part of the document content (Figure 1). EMBLs are used for multimedia retrieval with a camera phone. Users take a picture of an EMBL-signified document patch using a cell phone, and the multimedia associated with the EMBL-signified document location is displayed on the phone. Unlike a traditional barcode which requires an exclusive space, the EMBL construction algorithm acts as an agent to negotiate with a barcode reader for maximum user and document benefits. Because of this negotiation, EMBLs are optimally blended with content and thus have less interference with the original document layout and can be moved closer to a media associated location. Retrieval of media associated with an EMBL is based on the barcode identification of a captured EMBL. Therefore, EMBL retains nearly all barcode identification advantages, such as accuracy, speed, and scalability. Moreover, EMBL takes advantage of users' knowledge of a traditional barcode. Unlike Embedded Media Maker (EMM) which requires underlying document features for marker identification, EMBL has no requirement for the underlying features. This paper will discuss the procedures for EMBL construction and optimization. It will also give experimental results that strongly support the EMBL construction and optimization ideas.
Publication Details
  • Information Processing & Management, 46 (6), pp. 629-631
  • Nov 1, 2010

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This special issue brings together papers that describe some of the many ways that collaborative information seeking manifests itself. Some papers report on collaborative practices in a range of domains, including medical (Hertzum), legal (Attfield et al.), and online Q&A (Gazan). Others propose and evaluate models of collaborative activity (Evans and Chi; Evans et al.; Wilson and schraefel; Foley and Smeaton), and others describe systems and algorithms that support collaboration in various ways (Boydell and Smyth; Fernandez-Luna et al., Halvey et al., Morris et al.; Shah et al.).

Role-based results redistribution for collaborative information retrieval

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  • Information Processing & Management, 46 (6), pp. 773-781
  • Nov 1, 2010

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We describe a new approach for algorithmic mediation of a collaborative search process. Unlike most approaches to collaborative IR, we are designing systems that mediate explicitly-defined synchronous collaboration among small groups of searchers with a shared information need. Such functionality is provided by first obtaining different rank-lists based on searchers' queries, fusing these rank-lists, and then splitting the combined list to distribute documents among collaborators according to their roles. For the work reported here, we consider the case of two people collaborating on a search. We assign them roles of Gatherer and Surveyor: the Gatherer is tasked with exploring highly promising information on a given topic, and the Surveyor is tasked with digging further to explore more diverse information. We demonstrate how our technique provides the Gatherer with high-precision results, and the Surveyor with information that is high in entropy.