3968249
Topiary: a tool for prototyping location-enhanced applications
Location-enhanced applications use the location of people, places, and things to augment or streamline interaction. Location-enhanced applications are just starting to emerge in several different domains, and many people believe that this type of application will experience tremendous growth in the near future. However, it currently requires a high level of technical expertise to build location-enhanced applications, making it hard to iterate on designs. To address this problem we introduce Topiary, a tool for rapidly prototyping location-enhanced applications. Topiary lets designers create a map that models the location of people, places, and things; use this active map to demonstrate scenarios depicting location contexts; use these scenarios in creating storyboards that describe interaction sequences; and then run these storyboards on mobile devices, with a wizard updating the location of people and things on a separate device. We performed an informal evaluation with seven researchers and interface designers and found that they reacted positively to the concept.
8007626
DENIM: finding a tighter fit between tools and practice for Web site design
Through a study of web site design practice, we observed that web site designers design sites at different levels of refinement—site map, storyboard, and individual page—and that designers sketch at all levels during the early stages of design. However, existing web design tools do not support these tasks very well. Informed by these observations, we created DENIM, a system that helps web site designers in the early stages of design. DENIM supports sketching input, allows design at different refinement levels, and unifies the levels through zooming. We performed an informal evaluation with seven professional designers and found that they reacted positively to the concept and were interested in using such a system in their work.
6805196
Putting people in their place: an anonymous and privacy-sensitive approach to collecting sensed data in location-based applications
The emergence of location-based computing promises new and compelling applications, but raises very real privacy risks. Existing approaches to privacy generally treat people as the entity of interest, often using a fidelity tradeoff to manage the costs and benefits of revealing a person's location. However, these approaches cannot be applied in some applications, as a reduction in precision can render location information useless. This is true of a category of applications that use location data collected from multiple people to infer such information as whether there is a traffic jam on a bridge, whether there are seats available in a nearby coffee shop, when the next bus will arrive, or if a particular conference room is currently empty. We present hitchhiking, a new approach that treats locations as the primary entity of interest. Hitchhiking removes the fidelity tradeoff by preserving the anonymity of reports without reducing the precision of location disclosures. We can therefore support the full functionality of an interesting class of location-based applications without introducing the privacy concerns that would otherwise arise.
7311237
Marmite: end-user programming for the web
A tremendous amount of semi-structured data is available today on the web but is not necessarily in a form which is suitable for a user's tasks. For example, a website may show a listing of local events but a user wants to filter out those which are too far from him. To address this problem, we are developing a tool called Marmite that helps users extract data from web pages and create new applications using a dataflow architecture in a manner similar to Unix pipes. In this paper, we describe formative user studies, some evaluations of low-fidelity prototypes, and a set of design recommendations for this tool.
1564080
Privacy risk models for designing privacy-sensitive ubiquitous computing systems
Privacy is a difficult design issue that is becoming increasingly important as we push into ubiquitous computing environments. While there is a fair amount of theoretical work on designing for privacy, there are few practical methods for helping designers create applications that provide end-users with a reasonable level of privacy protection that is commensurate with the domain, with the community of users, and with the risks and benefits to all stakeholders in the intended system. Towards this end, we propose privacy risk models as a general method for refining privacy from an abstract concept into concrete issues for specific applications and prioritizing those issues. In this paper, we introduce a privacy risk model we have developed specifically for ubiquitous computing, and outline two case studies describing our use of this privacy risk model in the design of two ubiquitous computing applications.
2476013
The context fabric: an infrastructure for context-aware computing
Despite many sensor, hardware, networking, and software advances, it is still quite difficult to build effective and reliable context-aware applications. We propose to build a context infrastructure that provides three things to simplify the task of building context-aware applications: a context data store for modeling, storing, and distributing context data; a context specification language for declaratively stating and processing context needs; and protection mechanisms for safeguarding privacy needs.
7007390
Wrinkled flames and cellular patterns
We model flames and fire using the Navier-Stokes equations combined with the level set method and jump conditions to model the reaction front. Previous works modeled the flame using a combination of propagation in the normal direction and a curvature term which leads to a level set equation that is parabolic in nature and thus overly dissipative and smooth. Asymptotic theory shows that one can obtain more interesting velocities and fully hyperbolic (as opposed to parabolic) equations for the level set evolution. In particular, researchers in the field of detonation shock dynamics (DSD) have derived a set of equations which exhibit characteristic cellular patterns. We show how to make use of the DSD framework in the context of computer graphics simulations of flames and fire to obtain interesting features such as flame wrinkling and cellular patterns.
42258742
Discontinuous fluids
At interfaces between different fluids, properties such as density, viscosity, and molecular cohesion are discontinuous. To animate small-scale details of incompressible viscous multi-phase fluids realistically, we focus on the discontinuities in the state variables that express these properties. Surface tension of both free and bubble surfaces is modeled using the jump condition in the pressure field; and discontinuities in the velocity gradient field. driven by viscosity differences, are also considered. To obtain derivatives of the pressure and velocity fields with sub-grid accuracy, they are extrapolated across interfaces using continuous variables based on physical properties. The numerical methods that we present are easy to implement and do not impact the performance of existing solvers. Small-scale fluid motions, such as capillary instability, breakup of liquid sheets, and bubbly water can all be successfully animated.
761629
Web Services Based Configuration Management for IP Network Devices
The tasks of operating and managing diverse network devices from multiple vendors are getting more difficult and complicated. For that reason, IETF Netconf Working Group has been standardizing network configuration management. The Netconf protocol is an output of that standardization and can be used to effectively manage various devices on a network. However, it is still problematic for the manager to discover and manage configurable parameters in various devices. This paper proposes a method that can quickly discover devices and their parameters as well as methods to manipulate the configuration information on them. We present the architecture for XCMS-WS which meets this mechanism. Using the Web Services technologies, we have develioed a more powerful and flexible system than our previous XCMS. For validation, we have applied XCMS-WS for the configuration management of NG-MON, a distributed, real-time Internet traffic monitoring and analysis system.
10811173
EWS-Based Management Application Interface and Integration Mechanisms for Web-Based Element Management
Web-based network element management provides an administrator with the ability to configure and monitor network devices over the Internet using a Web browser. The most direct way to accomplish this is to embed a Web server [Embedded Web Server (EWS)] into a network device, and use that server to provide a Web-based management user interface constructed with HTML, graphics, Java and other features common to Web browsers. In this paper we present EWS-based management application interface mechanisms for use between embedded management applications and embedded Web servers. We propose a guideline for choosing an efficient interface mechanism, which is based on the characteristics of management information and Web documents. A Web-based management user interface through embedded Web servers has many advantages such as ubiquity, platform independence and user-friendliness. In order to be truly useful, a Web-based management user interface must have a low development cost and a short development time. We provide effective integration mechanisms for each interface. We validate these mechanisms by implementing them in an Internet router.
35128241
Graphs that are Almost Binary Trees
This paper studies embeddings of graphs in binary trees. The cost of such an embedding is the maximum distance in the binary tree between images of adjacent graph vertices. Several techniques for bounding the costs of such embeddings from above are derived; notable among these is an algorithm for embedding any outerplanar graph in a binary tree with a cost that is within a factor of 3 of optimal. A number of techniques for bounding the costs of such embeddings from below are developed; notable here are two techniques for inferring the presence of large separators in graphs. Finally, a number of characterizations are established of those families of graphs that are almost binary trees, in the sense that every graph in the family is embeddable in a binary tree within bounded cost.