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Ocean processes are complex and have a high variability in both time and space. Thus, ocean scientists must collect data over long time periods to obtain synoptic views and resolve multidimensional spatiotemporal variability. In this paper, we present a methodology for incorporating time-varying currents into a Markov Decision Process for persistent path execution by underwater gliders. The application...
In this work we argue that the high frequency spatial variations in the topological information of the face are important for Facial Expression Recognition. Stereo and laser scanner based datasets currently used are inherently regularized, resulting in the loss of high frequency information. We test our hypothesis on the dense gradient field from Photometric Stereo which preserves this high frequency...
Currently the standard clinical practice for measuring the motion of bones in a knee joint with sufficient precision involves implanting tantalum beads into the bones to act as fiducial markers prior to imaging using X-ray equipment. This procedure is invasive in nature and exposure to ionizing radiation imposes a cancer risk and the patient's movements are confined to a narrow field of view. In this...
Effective execution of a planned path by an underwater vehicle is important for proper analysis of the gathered science data, as well as to ensure the safety of the vehicle during the mission. Here, we propose the use of an unscented Kalman filter to aid in determining how the planned mission is executed. Given a set of waypoints that define a planned path and a dicretization of the ocean currents...
Building a photorealistic, 3D model of an object or a complete scene from image-based methods is a fundamental problem in computer vision, and has many applications in robotic perception, navigation, exploration and mapping. In this paper, we extend current state-of-the-art in the computation of depth maps by presenting an accurate and computationally efficient iterative hierarchical algorithm for...
Kinematic analysis of normal and artificial knee joints is an important diagnostic tool for the orthopaedic research community. Abnormal motion in a knee joint gives rise to pain and eventually causes chronic injury. Currently the standard way to measure the motion of bones in a knee joint with high precision is by implanting tantalum beads in the bones prior to imaging using X-ray equipment. This...
Autonomous guidance of agricultural vehicles is vital as mechanized farming production becomes more prevalent. It is crucial that tractor-trailers are guided with accuracy in both lateral and longitudinal directions, whilst being affected by large disturbance forces, or slips, owing to uncertain and undulating terrain. Previous research has been concentrated on trajectory control that provides longitudinal...
Measurement of the motion of the components in normal and artificial knee joints is a major goal of the orthopaedic research community. Abnormal motion in knee joints is a major cause of pain and often leads to chronic injury. Currently the standard way to measure the motion with enough accuracy is by implanting tantalum beads in the bones prior to imaging using X-ray equipment. However this technique...
The COmbat SAmple GEnerator (COSAGE) model is a stochastic, symmetric, two-sided combat simulation model implemented in SIMSCRIPT II.5. This model is primary used as a calibration for Attrition Calibration (ATCAL) base theater-level models including the Joint Integrated Contingency Model (JICM), Synthetic Theater Operations Research Model (STORM) (AF, follow-on to Thunder), and Integrated Theater...
This paper proposes a path planning algorithm and a velocity control algorithm for underwater gliders to persistently monitor a patch of ocean. The algorithms address a pressing need among ocean scientists to collect high-value data for studying ocean events of scientific and environmental interest, such as the occurrence of harmful algal blooms. The path planner optimizes a cost function that blends...
In the ocean science community, researchers have begun employing novel sensor platforms as integral pieces in oceanographic data collection, which have significantly advanced the study and prediction of complex and dynamic ocean phenomena. These innovative tools are able to provide scientists with data at unprecedented spatiotemporal resolutions. This paper focuses on the newly developed Wave Glider...
Coral reefs are biologically complex ecosystems that support a wide variety of marine organisms. These are fragile communities under enormous threat from natural and human-based influences. Properly assessing and measuring the growth and health of reefs is essential to understanding impacts of ocean acidification, coastal urbanisation and global warming. In this paper, we present an innovative 3-D...
This paper deals with the optimization of the design of a 4 degree-of-freedom robot dedicated to tele-echography. It has been designed to reproduce in real time on a patient, the medical gestures performed by a remote expert moving a fictive probe. Our goal is to optimize the kinematic structure to determine geometrical parameters, as they have a significant role in the singularities localization...
We propose a new high speed line tracing algorithm based on a well known differential geometric line extraction algorithm. The previously separate steps of line detection and line tracing are performed simultaneously. This allows the exclusion of non-candidates from processing. Exploiting the inherent continuity of lines and using extracted line characteristics in subsequent detection/tracing also...
In recent years, ocean scientists have started to employ many new forms of technology as integral pieces in oceanographic data collection for the study and prediction of complex and dynamic ocean phenomena. One area of technological advancement in ocean sampling if the use of Autonomous Underwater Vehicles (AUVs) as mobile sensor platforms. Currently, most AUV deployments execute a lawnmower-type...
Data collection using Autonomous Underwater Vehicles (AUVs) is increasing in importance within the oceanographic research community. Contrary to traditional moored or static platforms, mobile sensors require intelligent planning strategies to maneuver through the ocean. However, the ability to navigate to high-value locations and collect data with specific scientific merit is worth the planning efforts...
2D-3D image registration has become an important tool in many clinical applications such as image-guided surgery and the kinematic analysis of bones in knee and ankle joints. A limitation of this approach is the need to recalculate the voxel values in the 3D volume for every iteration of the registration procedure. In this paper we propose a new 2D-3D image registration algorithm which uses the projected...
3D computed tomography (CT) to single-plane 2D fluoroscopy registration is an emerging technology for many clinical applications such as kinematic analysis of human joints and image-guided surgery. However, previous registration approaches have suffered from the inaccuracy of determining precise motion parameters for out-of-plane movements. In this paper we compare kinematic measurements obtained...
This proceeding studies the optical fluorescence images of a porcine heart filled with microspheres of two colors, carmine and red. A significant difference in the total optical tissue attenuation coefficient was observed between excitation and emission for both carmine (excitation - 13 plusmn 4(1/mm) and emission - 9.4 plusmn 3(1/mm)) and red (excitation -29 plusmn 5(1/mm) and emission - 25 plusmn...
Future wireless networks will be loaded with voice, messaging, file transferring, multimedia teleconferencing, games, and Web browsing. With the increasing traffic and real time demand the current status of networking cannot meet the demands of future wireless applications. Traffic will be jammed on current wireless channels and customers will enter into a deadlock situation. Therefore, new models...
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