Gethin Wyn Roberts

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Accurate indoor positioning is required for a variety of commercial applications, including warehouse automation, asset tracking, emergency first-responders, and others. In fact, the general expectation of users today is for “GPS-like” positioning performance anywhere they go. The inherent limitations of GPS signal availability indoors and in(More)
A 1-year prospective analysis was undertaken of all non-day-case general surgery in a district general hospital. Using the Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM) scoring system 3004 patients were assessed. From the predictions of mortality and morbidity so obtained, a quality measure, the ratio of(More)
A detailed histopathological review was made of 408 cases randomly selected from all malignant melanomata diagnosed in New South Wales, Australia, during the period 1970 to 1976. The distribution of histological types in relation to age, sex and body site was similar to those reported elsewhere. Pigmentation was also related to the histological type of the(More)
BACKGROUND AND OBJECTIVES Our aim was to use a national electronic AKI alert to define the incidence and outcome of all episodes of community- and hospital-acquired adult AKI. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS A prospective national cohort study was undertaken in a population of 3.06 million. Data were collected between March of 2015 and(More)
An obvious difficulty of the Watson-Crick model of DNA is that the intertwining of the strands would seem to hinder their separation during replication. The nature of the difficulty is here made precise and is called the alignment problem. It is shown that the swivelase theory, found in current textbooks and thought to overcome the difficulty, does not in(More)
Global positioning systems (GPS) have in recent years been increasingly used to monitor the deformations of large structures, particularly the deflections of long suspension bridges. When appropriately employed, and with the presence of a strong satellite geometry, GPS can supply timely and accurate structural deformation information. However, the(More)
OBJECTIVES To identify any seasonal variation in the occurrence of, and outcome following Acute Kidney Injury. METHODS The study utilised the biochemistry based AKI electronic (e)-alert system established across the Welsh National Health Service to collect data on all AKI episodes to identify changes in incidence and outcome over one calendar year (1st(More)
The use of GPS for the deflection and deformation monitoring of structures has been under investigation for a number of years. Previous work has shown that GPS not only measures the magnitude of the deflection of the structure, but also it is able to measure the frequency of the movement. Both sets of information are useful for structural engineers when(More)
In 2005 The UK Department for Trade and Industry (DTI) commenced funding a project called Visualising Integrated Information on Buried Assets to Reduce Streetworks (VISTA). The project aims to precisely map buried assets (gas pipes, telecom cables, etc) and increase the efficiency of the process in challenging environments such as in urban canyons, where(More)