Visualizing the inner structure of n-body data using skeletonization

N-body simulations solve the n-body problem numerically and determine the trajectories of the n point masses. The result of these calculations is a huge amount of data detailing the positions and other properties of each body such as mass and velocity. To effectively draw conclusions from these data, one must employ scientific visualization to create images and movies that illustrate the structure of the data. We show that the computer animation technique of skeletonization can be applied to the volume data produced by n-body simulations in order to visualize the inner structure of the data. This novel application is compared to traditional rendering methods in terms of its ability to show this structure

Many-to-Many Invocation: A New Framework for Building Collaborative Applications in Ad Hoc Networks

Many-to-Many Invocation (M2MI) is a new paradigm for building collaborative systems that run in wireless proximal ad hoc networks of fixed and mobile computing devices. M2MI is useful for building a broad range of systems, including service discovery frameworks; groupware for mobile ad hoc collaboration; systems involving networked devices (printers, cameras, sensors); and collaborative middleware systems. M2MI provides an object oriented method call abstraction based on broadcasting. An M2MI invocation means ``Every object out there that implements this interface, call this method.\u27\u27. M2MI is layered on top of a new messaging protocol, the Many-to-Many Protocol (M2MP), which broadcasts messages to all nearby devices using the wireless network\u27s inherent broadcast nature instead of routing messages from device to device. In an M2MI-based system, central servers are not required; network administration is not required; complicated, resource-consuming ad hoc routing protocols are not required; and system development and deployment are simplified

Visualization `a la Unix

A visualization framework can be seen as a solution to a specialized data flow problem. Spiegel1 is a visualization framework which uses the Unix pipeline model to execute programs that visualize scientific data. A visualization program in Spiegel is constructed out of simple components with communication endpoints which can be con- nected together. Spiegel provides a graphical pro- gramming environment, which can be used to write programs using these components. This paper de- scribes the language used to define a Spiegel pro- gram, the graphical programming environment, and the Spiegel architecture

Many-to-Many Invocation: A New Object Oriented Paradigm for Ad Hoc Collaborative Systems

Many-to-Many Invocation (M2MI) is a new paradigm for building collaborative systems that run in wireless proximal ad hoc networks of xed and mobile computing devices. M2MI is useful for building a broad range of systems, including multiuser applications (conversations, groupware, multiplayer games); systems involving networked devices (printers, cameras, sensors); and collaborative middleware systems. M2MI provides an object oriented method call abstraction based on broadcasting. An M2MI invocation means \Every object out there that implements this interface, call this method. An M2MI-based application is built by de ning one or more interfaces, creating objects that implement those interfaces in all the participating devices, and broadcasting method invocations to all the objects on all the devices. M2MI is layered on top of a new messaging protocol, the Many-to-Many Protocol (M2MP), which broadcasts messages to all nearby devices using the wireless network\u27s inherent broadcast nature instead of routing messages from device to device. M2MI synthesizes remote method invocation proxies dynamically at run time, eliminating the need to compile and deploy proxies ahead of time. As a result, in an M2MI-based system, central servers are not required; network administration is not required; complicated, resource-consuming ad hoc routing protocols are not required; and system development and deployment are simplifi ed

A New Framework for Building Secure Collaborative Systems in Ad Hoc Network

Maturing software development organizations are beginning to identify a distinct role in the software team: Software Process Engineer. A software process engineer designs the software processes used by the organization. The software process includes the process content (identification of the roles, activities, and work products of the processes, along with specific techniques, tools, guidance, examples and other supporting information) and the lifecycle model (the ordering of and dependencies between software engineering activities and work products). A process engineer assembles a process from existing process components, choosing and tailoring components to provide the balance of agility and discipline necessary for their organization and projects. We have developed a graduate software engineering course to educate our students on the basic concepts of software process engineering. We use the OMG Software Process Engineering Metamodel and the IEEE Standard for Developing a Software Project Life Cycle Process as ways to model and compare process design alternatives and to provide mechanisms to assemble reusable process components into enactable processes. We use the Open Unified Process as an example process and we survey a wide range of techniques and methods that can be incorporated into a process. We use the Eclipse Process Framework Composer and associated process component libraries to assemble processes for specific projects. This paper describes the process engineering course and provides an informal assessment of the course effectiveness

Gesture Recognition with the Leap Motion Controller

The Leap Motion Controller is a small USB device that tracks hand and finger movements using infrared LEDs, allowing users to input gesture commands into an application in place of a mouse or keyboard. This creates the potential for developing a general gesture recognition system in 3D that can be easily set up by laypersons using a simple, commercially available device. To investigate the effectiveness of the Leap Motion controller for hand gesture recognition, we collected data from over 100 participants and then used this data to train a 3D recognition model based on convolutional neural networks, which can recognize 2D projections of the 3D space. This achieved an accuracy rate of 92.4% on held out data. We also describe preliminary work on incorporating time series gesture data using hidden Markov models, with the goal of detecting arbitrary start and stop points for gestures when continuously recording data

AstroDance: Engaging Deaf and Hard-of-Hearing Students in Astrophysics via Multimedia Performances

The dynamics of gravitating astrophysical systems such as black holes and neutron stars are fascinatingly complex, offer some of nature\u27s most spectacular phenomena, and capture the public\u27s imagination in ways that few subjects can. Here, we describe AstroDance, a multi-media project to engage deaf and hard-of-hearing (DHH) students in astronomy and gravitational physics. AstroDance incorporates multiple means of representation of scientific concepts and was performed primarily for secondary and post-secondary audiences at ~20 venues in the northeastern US prior to the historic first detection of gravitational waves. As part of the AstroDance project, we surveyed ~1000 audience members roughly split evenly between hearing and DHH audience members. While both groups reported statistically equivalent high-rates of enjoyment of the performance, the DHH group reported an increase in how much they learned about science at a statistically significant rate compared to the hearing audience. Our findings suggest that multi-sensory approaches benefit both hearing and DHH audiences and enable accessible participation for broader groups

Oscillating magnetic field disrupts magnetic orientation in Zebra finches, Taeniopygia guttata

Background Zebra finches can be trained to use the geomagnetic field as a directional cue for short distance orientation. The physical mechanisms underlying the primary processes of magnetoreception are, however, largely unknown. Two hypotheses of how birds perceive magnetic information are mainly discussed, one dealing with modulation of radical pair processes in retinal structures, the other assuming that iron deposits in the upper beak of the birds are involved. Oscillating magnetic fields in the MHz range disturb radical pair mechanisms but do not affect magnetic particles. Thus, application of such oscillating fields in behavioral experiments can be used as a diagnostic tool to decide between the two alternatives. Methods In a setup that eliminates all directional cues except the geomagnetic field zebra finches were trained to search for food in the magnetic north/south axis. The birds were then tested for orientation performance in two magnetic conditions. In condition 1 the horizontal component of the geomagnetic field was shifted by 90 degrees using a helmholtz coil. In condition 2 a high frequently oscillating field (1.156 MHz) was applied in addition to the shifted field. Another group of birds was trained to solve the orientation task, but with visual landmarks as directional cue. The birds were then tested for their orientation performance in the same magnetic conditions as applied for the first experiment. Results The zebra finches could be trained successfully to orient in the geomagnetic field for food search in the north/south axis. They were also well oriented in test condition 1, with the magnetic field shifted horizontally by 90 degrees. In contrast, when the oscillating field was added the directional choices during food search were randomly distributed. Birds that were trained to visually guided orientation showed no difference of orientation performance in the two magnetic conditions