have problems weighing the various factors that influence the need for roof repair. So, how can you do away with these traditional, bulky, tools, while improving service and the ability to train new staff? We devised a PDA-based expert system that uses artificial neural networks to provide a roofing advisor. Roofers might be familiar with a large number of roof types but concentrate on those fo...

The U.S. National Institute for Occupational Safety and Health (NIOSH) conducted a study to determine the effectiveness of a filtered air delivery system to reduce respirable dust exposure of roof bolter operators in underground coal mines. When performing roof bolting operations, roof bolter operators may experience exposure to high levels of respirable dust during a working shift, especially ...

In this work, an automated approach for 3D building roof modelling is presented. The method consists of two main parts, namely roof detection and 3D geometric modelling. For the detection, a combined approach of four methods achieved the best results, using slope-based DSM filtering as well as classification of multispectral images, elevation data and vertical LiDAR point density. In the evalua...

In February 2006, an outbreak of Legionnaires' disease (LD) was identified in Beachlands, a small, isolated east Auckland suburb. It was investigated through case finding, a case-control study, sampling potential sources of infection and by molecular typing (using sequence-based typing (SBT) of all Legionella pneumophila serogroup 1 (Lp1) isolates). Lp1 was isolated from the respiratory tract o...

Laser scanning is a new technology for obtaining Digital Surface Models (DSM) of the earth surface. It is fast method for sampling the earth surface with a high density and high point accuracy. In this paper a procedure for building detection and roof extraction from the DSM is presented. The procedure starts by re-sampling elevation as obtained by laser scanning into regular grid. The core par...

A 2D unsteady computational fluid dynamics (CFD) model is employed to simulate buoyancy-driven turbulent ventilation in attics with different pitch values and ceiling insulation levels under summer conditions. The impacts of roof pitch and ceiling insulation on the cooling load of gable-roof residential buildings are investigated based on the simulation of turbulent air flow and natural convect...

In this paper, a methodology is proposed for the geometric refinement of LiDAR building roof contours using high-resolution aerial images and Markov Random Field (MRF) models. The proposed methodology assumes that the 3D description of each building roof reconstructed from the LiDAR data (i.e., a polyhedron) is topologically correct and that it is only necessary to improve its accuracy. Since r...

Perceptions of the quality of roof harvested rainwater remain an impediment to widespread implementation of rainwater tanks on urban allotments. Previous literature reports on roof water quality have given little consideration to the relative significance of airborne environmental micro-organisms to roof catchment contamination and the issue of tank water quality. This paper outlines the findin...

BACKGROUND Ultrasonography of the hip has gained wide acceptance as a primary method for diagnosis, screening and treatment monitoring of developmental hip dysplasia in infants. The aim of the study was to examine the degree of concordance of two objective classifications of hip morphology and subjective parameters by three investigators with different levels of experience. METHODS In 207 con...