AuthorsAnwary, Arif Reza
MetadataShow full item record
AbstractIn this research, Procrustes and Euclidean distance matrix analysis (EDMA) have been investigated for analysing the three-dimensional shape and form of the human back. Procrustes analysis is used to distinguish deformed backs from normal backs. EDMA is used to locate the changes occurring on the back surface due to spinal deformity (scoliosis, kyphosis and lordosis) for back deformity patients. A surface topography system, ISIS2 (Integrated Shape Imaging System 2), is available to measure the three-dimensional back surface. The system presents clinical parameters, which are based on distances and angles relative to certain anatomical landmarks on the back surface. Location, rotation and scale definitely influence these parameters. Although the anatomical landmarks are used in the present system to take some account of patient stance, it is still felt that variability in the clinical parameters is increased by the use of length and angle data. Patients also grow and so their back size, shape and form change between appointments with the doctor. Instead of distances and angles, geometric shape that is independent of location, rotation and scale effects could be measured. This research is mainly focusing on the geometric shape and form change in the back surface, thus removing the unwanted effects. Landmarks are used for describing back information and an analysis of the variability in positioning the landmarks has been carried out for repeated measurements. Generalized Procrustes analysis has been applied to all normal backs to calculate a mean Procrustes shape, which is named the standard normal shape (SNS). Each back (normal and deformed) is then translated, rotated and scaled to give a best fit with the SNS using ordinary Procrustes analysis. Riemannian distances are then estimated between the SNS and all individual backs. The highest Riemannian distance value between the normal backs and the SNS is lower than the lowest Riemannian distance value between the deformed backs and the SNS. The results shows that deformed backs can be differentiated from normal backs. EDMA has been used to estimate a mean form, variance-covariance matrix and mean form difference from all the normal backs. This mean form is named the standard normal form (SNF). The influence of individual landmarks for form difference between each deformed back and the SNF is estimated. A high value indicates high deformity on the location of that landmark and a low value close to 1 indicates less deformity. The result is displayed in a graph that provides information regarding the degree and location of the deformity. The novel aspects of this research lie in the development of an effective method for assessing the three-dimensional back shape; extracting automatic landmarks; visualizing back shape and back form differences.
PublisherUniversity of Wolverhampton
TypeThesis or dissertation
DescriptionA thesis submitted to the department of Engineering and Technology in partial fulfilment of the requirements for the degree of Master of Philosophy in Production and Manufacturing Engineering at the University of Wolverhampton
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Spinal posture in different DanceSport dance styles compared with track and field athletes.Kruusamäe, Helena; Maasalu, Katre; Wyon, Matthew; Jürimäe, Toivo; Mäestu, Jarek; Mooses, Martin; Jürimäe, Jaak (Lithuanian Medical Association, 2015-11)Background and objective: In DanceSport, athletes train for many years to develop a very specific posture. Presently there are few data as to whether these adaptations are habitual or cause permanent anatomical changes to the spine. The aim of the current study was to evaluate lumbar lordosis and thoracic kyphosis of the international level DanceSport dancers using track and field athletes as controls. Materials and methods: Thirty competitive DanceSport couples (15 men aged 23.4 6.6 years; 15 women aged 22.5 6.4 years) and 29 track and field athletes (16 mean aged 27 4.4 years and 13 women aged 22 4.1 years) volunteered. Twelve couples were Standard, 7 Latin American and 11 were Ten Dance couples. Thoracic kyphosis and lumbar lordosis angle were assessed in lateral view using a Vertebral Fracture Assessment scan. Results: DanceSport athletes had smaller S-shaped vertebral curvatures compared to track and field athletes. Male (5.7 4.78) and female dancers (8.7 5.98) had significantly smaller lumbar lordosis angle compared to their track and field counterparts (22.3 9.98 for men; 20.3 5.98 for women).Femaledancers(25.3 8.08)alsodemonstratedsignificantly smallerthoracickyphosis angle than female track and field (32.1 8.98) participants. It was further revealed that female Latin American dancers had significantly smaller lumbar lordosis values (3.7 3.18) compared with female Standard (10.7 6.18) and Ten Dance dancers (9.7 5.58). Conclusions: The results of the present study suggest that smaller S-shaped vertebral curvatures of DanceSport athletes compared with track and field athletes are permanent changes rather than habitual.
Transition from elastic to plastic deformation as asperity contact size is increasedYong, C. W.; Smith, W.; Dhir, A.; Kendall, K. (Tribology Letters, 2007-01)Contacts between a clean sodium chloride pyramidal shaped asperity and a plane NaCl surface have been investigated by molecular dynamics simulations. For small contacts, a few atoms across, the asperity jumped to contact and behaved elastically as normal load was applied. Then, when the force was reversed to detach the asperity, brittle failure occurred without any damage to the crystalline materials. However, as the contact size of the asperity was increased to 6×6 atoms in area, the mechanism of detachment was seen to alter. The jump to contact was elastic and damage free, but the separation could not be achieved elastically, but required plastic deformation, giving extensive energy dissipation and severe damage as edge defects propagated through the asperity. Above this contact size, plastic flow was dominant. However, there is clearly a further transition back to elastic fracture once the asperity becomes large enough for Griffith-type cracking to propagate above 1μm in size, since large sodium chloride contacts are known to be brittle above the micrometre scale, depending on the presence of crack initiating defects. Transition from elastic to plastic deformation as asperity contact size is increased | Request PDF. Available from: https://www.researchgate.net/publication/225130915_Transition_from_elastic_to_plastic_deformation_as_asperity_contact_size_is_increased [accessed Jul 05 2018].
Empirical Relationship between Rock Structure Rating and Modulus of DeformationRama Sarma, K.; Sarsby, Robert W. (ASCE Research Library, 2005)During the early stages of construction of a railway line in southeast India, the tunneling works encountered numerous problems, such as rock falls, major water inflow, etc. In order to progress the works, it was necessary to undertake thorough classification of the rock masses and to obtain values of the in situ modulus of deformation for inputting into numerical analyses. It was not feasible to conduct a large number of in situ determinations of the modulus of deformation. Hence, an attempt was made to establish an empirical relationship between rock structure rating and modulus of deformation (Em) for the rock masses through which the railway passed. This was done using data from tests conducted on rock samples taken from 45 boreholes at various locations along the railway line, particularly in tunnel sections where distress was observed. (ASCE)