Mathematical modelling is widely used in the field of biomechanics. The traditional approach to investigate spine related injuries is to check the strength of the components of the spine. Spinal stability approach focuses on the force polygons formed by the body weight, muscle forces, ligament forces and external load. This force polygon is expected to stay within the boundaries of the spine to ensure stability. Proving the possibility of one force polygon within the spine boundaries proves the stability of the spine. This study focuses on the full curvature of the spine for spinal stability investigations in a lifting activity. An experiment has been designed to investigate the postural differences in males and females by measuring the full spinal curvature with a skin surface device. Distributed body weight force, with increased detail of muscle and ligament forces acting on the spine have been modelled by writing a code in Visual Basic, while lifting a load from the boot of a car in the sagittal plane. This model is flexible enough to reflect changes in body weight parameter. Results show that there is a difference between male and female postures during the full span of lifting activities. Application of individual muscle forces provides greater control of stability at each vertebral level. By considering the elongation of the ligaments and the force requirements of the muscle groups, it is possible to diagnose soft tissue failure. The differences in posture result in different moment arms for muscles and ligaments causing different loading on the spine. Most critical postures have been identified as the fully flexed postures with external load acting on the spine. Conceptual design ideas have been proposed to assist lifting a load from the boot of a car to eliminate the excessive flexion and loading on the spine.

Medical image is a core step of medical diagnosis and has been diffusely applied in modern medical domain. The technology of modern medical image is more and more mature which could present images in different modes and features. Medical image fusion is the technology that could compound two mutual images into one according to certain rules to achieve clear visual effect. By observing medical fusion image, doctor could easily confirm the position of illness. According to the mutual features of CT medical image and MRI medical image, based on the technology of wavelet transform, the paper presents twp effective and applied medical image fusion methods. The first method is based on the features of certain area. The principle is to construct weighted factor and matching degree with certain related parameters to compound the area of high frequency which presents the detailed information. To the area of low frequency, principle of maximum absolute value is selected. Finally we get the fusion image by wavelet reconfiguration. By estimate of subjectivity and objectivity, the method is applied that could export excellent visual effect and good parameters. The other method is based on lifting wavelet. It decomposes the original image to area of low frequency and high frequency, and then transforms them with different fusion rules. To area of low frequency, weighted fusion is applied and to area of high frequency, rule of maximum standard deviation is chosen. Finally we get fusion image from wavelet reconstruction. By the estimate of subjectivity and objectivity, the method is an applied and excellent way that keeps the detailed information effectively and presents clear profile. At the same time, the executed time is shorter than others.

Master of Science / Department of Industrial & Manufacturing Systems Engineering / Todd W. Easton / Integer programming (IP) has been and continues to be widely used by industries to minimize cost and effectively manage resources. Faster computers and innovative IP techniques have enabled the solution to many large-scale IPs. However, IPs are NP-hard and many IPs require exponential time to solve. Lifting is one of the most widely used techniques that helps to reduce computational time and is widely applied in today's commercial IP software. Lifting was first introduced by Gomory for bounded integer programs and a theoretical and computationally intractible technique to simultaneously lift sets of variables was introduced by Zemel in 1978. This thesis presents a new algorithm called the Maximal Simultaneous Lifting Algorithm (MSLA), to simultaneously uplift sets of binary integer variables into a cover inequality. These lifted inequalities result in strong inequalities that are facet defining under fairly moderate assumptions. A computational study shows that this algorithm can find numerous strong inequalities for random Knapsack (KP) instances. The pre-processing time observed for these instances is less than 1/50th of a second, which is negligible. These simultaneously lifted inequalities are easy to find and incorporating these cuts to KP instances reduced the solution time by an average of 41%. Therefore, implementing MSLA should be highly beneficial for large real-world problems.

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Lifting and overstraining are major causative factors related to musculoskeletal injuries and low back pain. A great number of work-related injuries arise from the handling and/or mishandling of materials. Hence there is a need to quantify risk factors in situ and develop guidelines for safe lifting practises in industry. The aim of this study was to make appropriate in situ quantification, within a commercial warehouse, of the stresses and physical demands imposed on the worker when performing two handed lifts in the sagittal plane. The performance of employees was assessed under normal working conditions through an observational methodology of data collection. Task performance evaluation was based on detailed measurement of all containers handled, an activity and time analysis, and the 'Work Practices Guide to Manual Lifting’ (NIOSH, 1981) which was used as the primary guide to developing theoretical recommendations to probable MMH risk factors for the workers involved. Of the 191 tasks analysed 103 were deemed unsuitable. Appropriate task factor adjustments were made where necessary to both the frequency and Hfactors (horizontal distance between the centre of gravity of the container and that of the worker) in order to reduce the risk factor for the workers

Master of Science / Department of Industrial and Manufacturing Systems Engineering / Todd W. Easton / Integer programming is an important discipline in operation research that positively impacts society. Unfortunately, no algorithm currently exists to solve IP's in polynomial time. Researchers are constantly developing new techniques, such as cutting planes, to help solve IPs faster. For example, DeLissa discovered the existence of equality cuts limited to zero and one coefficients for the multiple knapsack equality problem (MKEP). An equality cut is an improper cut because every feasible point satisfies the equality. However, such a cut always reduces the dimension of the linear relaxation space by at least one. This thesis introduces lifted equality cuts, which can have coefficients greater than or equal to two. Two main theorems provide the conditions for the existence of lifted equalities. These theorems provide the foundation for The Algorithm of Lifted Equality Cuts (ALEC), which finds lifted equality cuts in quadratic time. The computational study verifies the benefit of lifted equality cuts in random MKEP instances. ALEC generated millions of lifted equality cuts and reduced the solution time by an average of 15%. To the best of the author's knowledge, ALEC is the first algorithm that has found over 30.7 million cuts on a single problem, while reducing the solving time by 18%.

Please read the abstract in the section 00front of this document / Thesis (PhD (New Testament Studies))--University of Pretoria, 2008. / New Testament Studies / unrestricted

O objetivo deste estudo foi analisar o controle postural diante da previsibilidade da carga elevada através de ação manual e da demanda atencional promovida pelo acréscimo de um alvo espacial na tarefa. Quinze sujeitos do sexo masculino (idade média 22,8+3,5 anos) realizaram a tarefa de elevação de uma caixa por meio da preensão manual, com massa variável (1, 3 e 5kg) nas condições previsível ou imprevisível. A tarefa também era executada em uma condição de maior demanda atencional promovida pela colocação de um alvo frontal, que deveria ser atingido por um facho de luz laser, cuja fonte estava fixada na caixa elevada pelo sujeito. Foram analisados o comportamento do centro de pressão (CP) e a cinemática das principais articulações e do movimento da caixa. Os resultados indicaram que a imprevisibilidade sobre a massa da caixa aumentou a oscilação do CP. Aumento da oscilação do CP também foi observado na situação de redução de massa, mesmo quando os sujeitos tinham conhecimento da mudança. A situação de pontaria em alvo induziu redução (a) do deslocamento do CP, (b) velocidade de elevação da caixa, e (c) amplitude de movimento do tornozelo e quadril. Estes resultados indicam que a previsibilidade sobre a ação de forças externas no corpo, demanda espacial da tarefa manual, e organização/feedback do movimento da tentativa anterior interagem para afetar o controle postural / The aim of this study was to analyze postural control as a function of predictability of a load lifted with the hands, and demand of spatial accuracy in the task. Fifteen males (mean age: 22.8 3.5 years) lifted boxes with variable masses (1, 3 and 5 kg), in conditions of predictable or unpredictable load. The task was performed either under lower spatial accuracy demand or aiming at a spatial target. Displacement of center of pressure (CP) and kinematics of the main joints/box motion were analyzed to access postural perturbation induced by the lifting task. Results showed that unpredictability about mass of the box enhanced CP displacement. Enhanced CP displacement was also observed in situations of decreased mass regarding the previous trial, even when participants were aware about the change. The pointing task induced decreased (a) CP displacement, (b) box lifting velocity, and (c) ankle and hip motion amplitude. These results indicate that predictability about external forces acting on the body, spatial demand of manual tasks, and movement organization/feedback of the previous trial interact to affect postural control

The diploma thesis deals with a design of a rotating part of a crane trolley of a scrap crane with a load capacity of 110,000 kg, which is situated in an exterior environment. The aim of the diploma thesis is a design and calculation verified design of the lifting mechanism, rotation mechanism and the design of a spacious traverse, which is used for the manipulation of the scrap trough and casting ladle.

The work deals with construction project of manipulator for loading of fruit products to a means of haulage (lorry semi-trailers, railway wagons). One part of the writnig is an idea concept of whole machinery and a detailed project of a lifting part with its strentght calculation. That was firstly worked out manually as a design and then subsequently optimalised by the Finite Element Method. Design documentation was made up based on the construction project and the calculated values.