Search

Feline lymphocytic-plasmacytic gingivitis/stomatitis (LPGS) or caudal stomatitis is an inflammatory disease that causes painfully erosive lesions and proliferations of the oral mucosa. The disease is difficult to cure and can affect cats at an early age, resulting in lifetime therapy. In this study, a new treatment using a combination of bovine lactoferrin (bLf) oral spray and oral piroxicam was investigated using a randomized double-blinded clinical trial in 13 cats with caudal stomatitis. Oral lesion grading and scoring of clinical signs were conducted during and after the trial to assess treatment outcome. Oral mucosal biopsies were used to evaluate histological changes during and after treatment.Clinical signs were significantly improved in 77% of the cats. In a 4-week study, clinical signs were considerably ameliorated by oral piroxicam during the first 2 weeks. In a 12-week study, the combined bLf oral spray and piroxicam, when compared with piroxicam alone, exhibited an enhanced effect that reduced the severity of the oral lesions (P = 0.059), while also significantly improving clinical signs (P

For a vision system to infer 3D object features (e.g., point features or line features) from 2D image features and to predict 2D image features from 3D object features, the transformation between the 2D image coordinate system and the 3D object coordinate system must be known. Determining this transformation is called (geometric) camera calibration. This 2D-3D transformation varies when the camera is moved by a robot. This paper presents a simple two-stage (off-line stage and on-line stage) method for calibrating a camera mounted on a robot. The off-line stage includes off-line calibration of the camera, the robot, and the robot-camera (or hand-eye) relation. The on-line stage can be divided into an initial calculation step and a re-calibration step. The initial step is computationally simple since it only involves one or two matrix multiplications of dimension less than four. The derived calibration accuracy from this initial step depends on the accuracy of the off-line camera/robot calibration. Experimental results show that the calibration accuracy is better than "1 part in 1000" without special robot calibration. Higher accuracy can be obtained with more sophisticated robot calibration, or with the re-calibration step using the extended Kalman filtering techniques. Some new insights to the conventional camera calibration methods are also given.

An important subject in computer vision is to determine 3D scene structure and motion from multiple 2D images taken by one or more, stationary or moving cameras. When there is no relative motion among the objects in view and the camera, and only one fixed camera is available, one tries to extract 3D information using techniques such as shape from shading, or shape from texture. When there is no relative motion, but more than one camera is available, shape from stereo is applicable. Suppose there is relative motion (which may be due to the motion of one or more objects, the motion of the camera, or both), 3D information can be obtained by the techniques generally referred to as shape from motion. If there is motion and more than one camera, one can integrate the information from both the stereo module and the motion module, e.g., [Mit88], [Wax88], Note that stereo problem can be treated as a special case of motion if the spatial distribution of the camera is considered as the result of "instantaneous" camera movement.

An approach is introduced to estimating object surfaces in 3D space from a sequence of images. A 3D surface of interest is modeled as a function known up to the values of a few parameters. Surface estimation is then treated as the general problem of maximum-likelihood parameter estimation based on two or more functionally related data sets, which constitute a sequence of images taken at different locations and orientations. Experiments are run to illustrate the various advantages of using as many images as possible in the estimation and of distributing camera positions from first to last over as large a baseline as possible. The authors introduce the use of asymptotic Bayesian approximations to summarize the useful information in a sequence of images, thereby drastically reducing both storage and processing. This results in a Bayesian estimator for the surface parameters. All the usual tools of statistical signal analysis can be brought to bear, the information extraction appears to be robust and computationally reasonable, the concepts are geometric and simple, and essentially optimal accuracy should result. >

Virtual reality (VR) has been a promising technique to provide an immersive experience. Comparing to traditional multimedia, when users want to take a rest or change the position such as sitting down, the chair might not be sittable because of the inconsistency between the physical and the virtual chair. In this work, we utilized a tracker attached to a physical chair and conducted a user study to explore the sitting behavior when they interact with different forms of the virtual chair. Results indicate that visualizing each part of the chair could provide different information and affect trust and preference.

In this paper, we consider a multi-camera vision system mounted on a moving object in a static three-dimensional environment. By using the motion flow fields seen by all of the cameras, an algorithm which does not need to solve the point-correspondence problem among the cameras is proposed to estimate the 3D ego-motion parameters of the moving object. Our experiments have shown that using multiple optical flow fields obtained from different cameras can be very helpful for ego-motion estimation.

We propose a real-time excavation simulation system for interactive gameplay in Virtual Reality. In order to increase the player's immersion, our simulation system will produce actual potholes and clods according to the depth and angle of the players excavation. We divide the process into three phases: ground deformation, clod generation and clod fragmentation. In ground deformation, we describe how to simulate the topographic changes before and after excavation. In clod generation, we describe how to generate the clod which mesh matches the depth and angle of the players excavation action. In clod fragmentation, the clods are broken and fall as the shovel lifts. This simulation system can create excavation effects on different geologies by changing the material of the ground and clods.