IMPROVING THE BUSINESS TRAJECTORY AMONG SMALL AND MEDIUM SIZE CONSTRUCTION FIRMS IN SOUTH AFRICA

Published ArticleThe Construction Industry Development Board (cidb) register of contractors shows that small and medium sized enterprises (SMEs) outnumber established firms in South Africa. However, the failure rate of SME businesses, which has increased in recent years, constitutes a source of concern in the industry. This situation is reflected in the limited number of successful construction SMEs as a percentage of the total registered firms in the industry. The research design for the study reported on entailed semi-structured and unstructured interviews, which were conducted over an extensive period of time to gather sufficient information from the research participants. However, the preliminary findings that form the nexus of this paper are based on the reviewed literature, and a pilot study that was conducted among a purposive sample of construction SMEs - Grades 1 to 5 on the cidb register. It is notable that the initial findings suggest that construction SMEs often encounter difficulty in securing projects, fail to realise core organisational objectives and goals, and are unable to gain cost advantages over their immediate rivals, which affects their business performance. Thus it appears that more effort is required to improve the business performance of construction SMEs in South Africa

Improving the business trajectory among small and medium size construction firms in South Africa

Published ArticleThe Construction Industry Development Board (cidb) register of contractors shows that small and medium sized enterprises (SMEs) outnumber established firms in South Africa. However, the failure rate of SME businesses, which has increased in recent years, constitutes a source of concern in the industry. This situation is reflected in the limited number of successful construction SMEs as a percentage of the total registered firms in the industry. The research design for the study reported on entailed semi-structured and unstructured interviews, which were conducted over an extensive period of time to gather sufficient information from the research participants. However, the preliminary findings that form the nexus of this paper are based on the reviewed literature, and a pilot study that was conducted among a purposive sample of construction SMEs - Grades 1 to 5 on the cidb register. It is notable that the initial findings suggest that construction SMEs often encounter difficulty in securing projects, fail to realise core organisational objectives and goals, and are unable to gain cost advantages over their immediate rivals, which affects their business performance. Thus it appears that more effort is required to improve the business performance of construction SMEs in South Africa

Shear stress and the vessel wall : in vivo studies applying 3-D finite element modelling

Atherosclerosis, a degenerative arterial disease, is a leading cause of death in the western society. It cau cause dysfunction of the heart, stroke or peripheral vascular disease by limiting the blood supply to the heart, the brain, the abdominal organs and the legs. The narrowing of those arteries originates from the build up of 'afherosclerotic' plaques in the arterial wall. Such plaques are the result of accumulating lipids and accompanying reactive processes into the vessel wall. Several risk factors are known to induce and innuence the progression of this disease like hypercholesterem

Fast and Accurate Pressure-Drop Prediction in Straightened Atherosclerotic Coronary Arteries

Atherosclerotic disease progression in coronary arteries is influenced by wall shear stress. To compute patient-specific wall shear stress, computational fluid dynamics (CFD) is required. In this study we propose a method for computing the pressure-drop in regions

Model-based cap thickness and peak cap stress prediction for carotid MRI

A rupture-prone carotid plaque can potentially be identified by calculating the peak cap stress (PCS). For these calculations, plaque geometry from MRI is often used. Unfortunately, MRI is hampered by a low resolution, leading to an overestimation of cap thickness and an underestimation of PCS. We developed a model to reconstruct the cap based on plaque geometry to better predict cap thickness and PCS. We used histological stained plaques from 34 patients. These plaques were segmented and served as the ground truth. Sections of these plaques contained 93 necrotic cores with a cap thickness <0.62 mm which were used to generate a geometry-based model. The histological data was used to simulate in vivo MRI images, which were manually delineated by three experienced MRI readers. Caps below the MRI resolution (n = 31) were (digitally removed and) reconstructed according to the geometry-based model. Cap thickness and PCS were determined for the ground truth, readers, and reconstructed geometries. Cap thickness was 0.07 mm for the ground truth, 0.23 mm for the readers, and 0.12 mm for the reconstructed geometries. The model predicts cap thickness significantly better than the readers. PCS was 464 kPa for the ground truth, 262 kPa for the readers and 384 kPa for the reconstructed geometries. The model did not predict the PCS significantly better than the readers. The geometry-based model provided a significant improvement for cap thickness estimation and can potentially help in rupture-risk prediction, solely based on cap thickness. Estimation of PCS estimation did not improve, probably due to the complex shape of the plaques

Is it safe to implant bioresorbable scaffolds in ostial side-branch lesions? Impact of 'neo-carina' formation on main-branch flow pattern. Longitudinal clinical observations

Formation of a 'neo-carina' has been reported after bioresorbable vascular scaffolds (BVS) implantation over side-branches. However, as this 'neo-carina' could protrude into the main-branch, its hemodynamic impact remains unknown. We present two cases of BVS implantation for ostial side-branch lesions, and investigate the flow patterns at follow-up and their potential impact. Computational fluid dynamics analysis was performed, using a 3D mesh created by fusion of 3-dimensional angiogram with optical coherence tomography images. In our first case, mild disturbances were seen when 'neo-carina' did not protrude perpendicularly into the main branch. In the second case, extensive flow re-distribution was observed due to a more pronounced protrusion of the 'neo-carina'. Importantly, these areas of hemodynamic disturbance were observed together with lumen narrowing in a non-stenotic vessel segment. Our case observations highlight the importance of investigating the hemodynamic consequences of BVS implantation in bifurcation lesions and illustrate a novel method to do so invivo