Sensor data fusion is an important and di cult requirement in marine robotics. This paper examines the role of sensor fusion in three di erent application areas: navigation of autonomous underwater vehicles, acoustic scene reconstruction, and ocean data assimilation. The research issues encountered in these problems include management of uncertainty, modeling of sensor physics, vehicle and envi...

One of the most challenging aspects of concurrent mapping and localization (CML) is the problem of data association. Because of uncertainty in the origins of sensor measurements, it is difficult to determine the correspondence between measured data and features of the scene or object being observed, while rejecting spurious measurements. However, there are many important applications of mobile ...

BACKGROUND We aimed to explore if increasing the amount of relevant information relayed in referral letters between general practitioners (GPs) or family physicians and hospital specialists helps in the scheduling of appointments for patients. We report a before and after study comparing outcomes before and after the introduction of software to assist referral writing. METHODS The participan...

We describe a novel application of uncalibrated stereo reconstruction to Roentgen Stereophotogrammetry Analysis (RSA). In RSA, stereo X-ray images are taken of a bone containing a prosthesis (e.g. a replacement knee) and a number of metal markers. The aim is to recover the relative position of the prosthesis and markers in 3D. Accuracy in previous RSA methods has been limited by two factors: ma...

This paper demonstrates the use of nonlinear image decomposition, in the form of a sieve, applied to the task of audiovisual speech recognition of a database of the letters A–Z for ten talkers. A scale based feature vector is formed directly from the grayscale pixels of an image containing the talkers mouth on a per frame basis. This is independent of image amplitude and position information an...

This paper describes a Concurrent Mapping and Localisation (CML) algorithm suitable for localising an Autonomous Underwater Vehicle (AUV). The proposed CML algorithm uses a standard off-the-shelf sonar for sensing the environment. The returns from the sonar are used to detect targets in the vehicle’s vicinity. These targets are used in conjunction with a vehicle model by the CML algorithm to co...

Gabor feature space is elaborated for representation, processing and segmentation of textured images. As a first step of preprocessing of images represented in this space, we introduce an algorithm for Gabor feature space denoising. It is a geometric-based algorithm that applies diffusion-like equation derived from a minimal weighted area functional, introduced previously and applied in the con...

We reexamine the role of time in the loss of information from working memory, the limited information accessible for cognitive tasks. The controversial issue of whether working memory deteriorates over time was investigated using arrays of unconventional visual characters. Each array was followed by a postperceptual mask, a variable retention interval (RI), and a recognition probe character. Dr...

Motion analysis often relies on differencing operations that inherently amplify noise and are hindered by the spatial correspondence problem. An alternative approach is proposed using AIJSA (Adaptive learning Image and Signal Analysis) to detect differences in types of motion by classifying the imaging effects of the motion in single frames. With an appropriate feature set, the ALISA engine acc...