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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Entry-lane capacity analysis of roundabouts in Texas using VISSIM, SIDRA, and the highway capacity manual

Mills, Alison Fayre 29 September 2011 (has links)
Road safety and traffic congestion are two of the critical issues facing the transportation profession today. As a means to promote safety and efficiency at United States intersections modern roundabouts are becoming more and more common. Over the last ten years, roundabouts implementation methodologies have been developed using data collected at U.S. roundabouts. These methodologies were first published in National Cooperative Highway Report 572: Roundabouts in the United States and more recently in the second edition of the national roundabout guidelines. This work attempts to validate the use of these methodologies for roundabouts in the state of Texas and also enhance guidelines for evaluating roundabout operations by exploring the effects of exiting flow, origin-destination patterns, and mean speed on roundabout entry-lane capacity. Capacity results from VISSIM are compared to the Highway Capacity Manual entry-lane capacity curve and results from SIDRA. / text
212

Management of cervical biomechanical dysfunction in schoolboy rugby players using a manual physiotherapy technique / Linda Steyn

Steyn, Linda January 2005 (has links)
Aims: The primary physiotherapeutic aims of the study were to validate a manual physiotherapy evaluation technique in the assessment of cervical biomechanical dysfunction, and to test the effectiveness of a manual physiotherapy treatment technique in the correction of cervical biomechanical dysfunction. The primary educational aims were to test the effectiveness and safety of a therapeutic exercise programme for the correction of biomechanical dysfunction as well as the effectiveness of a neck rehabilitation programme for improving neck muscle strength. Design: A four group experimental design with three pre-test - post-test groups and a control group was used for the investigation. Sample: The subjects were South African schoolboy rugby players between the ages of 15 and 18 years. Groups I and 2 presented with biomechanical dysfunction of their cervical spines, Group 3 had no biomechanical dysfunction of their cervical spines and the players of Group 4, the control group, presented with or without biomechanical dysfunction of their cervical spines. Each group consisted of 25 players. Method: Group I received manual physiotherapy with x-rays before and after treatment. Groups 2 and 3 performed a therapeutic exercise programme, with before and after x-rays, and Group 4 received no intervention between their sets of x-rays. Following the second set of x-rays all the players from Groups I, 2 and 3 performed the neck rehabilitation programme after which a third set of x-rays were taken. Results: The results validated the manual physiotherapy evaluation technique. The manual therapy treatment technique used in the treatment of Group I showed highly significant improvements in cervical biomechanical function. Results for Group 2 following the therapeutic exercise programme showed moderate practically significant improvements in cervical biomechanical dysfunction. The therapeutic exercise programme for the correction of biomechanical dysfunction was found to be very safe with only small significant changes in x-ray measurements (Group 3). The results of the control group showed a negative trend of small statistical significance. A highly significant improvement in cervical circumference as moderate significant improvement in biomechanical function was found following the neck rehabilitation programme. Conclusion: It could therefore be concluded that the manual physiotherapy evaluation technique for motion segment analysis was indeed valid in determining biomechanical dysfunction of the cervical spine. The manual physiotherapy treatment technique as well as the therapeutic exercise programme for the correction of biomechanical dysfunction was found to be effective in the correction of cervical biomechanical dysfunction. It could further be concluded that the therapeutic exercise programme was safe to be performed by players without biomechanical dysfunction. The neck rehabilitation programme was effective in improving cervical circumference as well as cervical biomechanical function. / Thesis (Ph.D. (Education))--North-West University, Potchefstroom Campus, 2005.
213

Diagnóstico de las dificultades en el aprendizaje de la lecto-escritura, nivel primario, La Pampa

Pruzzio de Di Pego, Vilma January 1987 (has links)
No description available.
214

A BIOMECHANICAL ANALYSIS OF A SPECIALIZED LOAD CARRIAGE TECHNIQUE AND THE DEVELOPMENT OF AN ASSISTIVE LOAD CARRIAGE DEVICE

Kudryk, IAN 29 September 2008 (has links)
During field observations of professional movers, it was noticed that some experienced movers carried loads posterior to their pelvis. The purpose of this study was two-fold: (1) to assess the biomechanical differences between hand-held load carriage anterior (AC) and posterior (PC) to the pelvis; and, (2) to determine if an assistive load carriage device could reduce muscle effort while carrying loads either anterior or posterior to the pelvis. In the first laboratory study, an electromyographic (EMG) analysis was conducted while participants carried a load on a treadmill using AC and PC techniques. The subjects conducted three trials of AC and PC techniques while EMG data were being collected. All trial data were normalized to their respective iMVE values. An amplitude probability distribution function (APDF) was used to compare EMG amplitudes between carrying techniques. Results indicated that PC reduced EMG activity of the erector spinae (>50% reduction), trapezius, and anterior deltoid (p<0.05) as well as increasing EMG activity in the posterior deltoid (p<0.05). Eighty percent of the subjects reported that the PC method felt awkward. Due to its awkwardness, many individuals may not use the PC technique; thus, the second purpose of the study was to design an assistive movers’ pack to aid in AC and PC techniques and make the PC method easier to perform. In the second study, subjects were asked to walk unloaded while EMG was recorded. The subjects then performed the AC and PC methods with and without the assistive device. All EMG signals were normalized to unloaded gait followed by EMG APDF analyses. Findings from the first study were confirmed, in that PC, compared to AC significantly reduced erector spinae activity (p<0.05) and focused shoulder activity to the posterior deltoid. Secondly, the assistive device effectively reduced flexor digitorum activity (>40% reduction, p<0.03) and anterior deltoid activity (>75% reduction, p=0.5) in both AC and PC. Erector spinae EMG remained similar to their respective unassisted conditions. The assistive load carriage device may be an effective ergonomic tool in both AC and PC techniques. Subjective surveys indicate that the assistive device decreased the awkwardness in performing the PC technique. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2008-09-29 16:58:19.305
215

The effect of the duration and amplitude of spinal manipulation therapy on the spinal stiffness of a feline model

Vaillant, Michele Unknown Date
No description available.
216

Förbättrad manuell styrning av staplingskran

Wessén, Mikael January 2015 (has links)
Detta examensarbete är utfört hos Swisslog under våren 2013. De hade problem med den manuella styrningen av deras pallstaplingskran för höglager, som upplevdes ryckig och svår att kontrollera vid låga hastigheter. Huvudsyftet var att undersöka varför detta fenomen uppstod och hur det kunde lösas med både hård- och mjukvarumässiga metoder. Utöver detta undersöktes hur produktionskostnaden, för delarna av kranen som rör den manuella styrningen, kunde reduceras. Det upplevda fenomenet är känt som biodynamic feedthrough. Det innebär att konstruktionens acceleration matas genom operatörens kropp och skapar en återkoppling till styrdonet, i detta fall en joystick. Operatörens hand ger en oavsiktlig störsignal som gör systemet instabilt som i sin tur skapar en oscillation som ökar i amplitud och är svår eller omöjlig att stoppa. Den föreslagna lösningen är att digitalt lågpassfiltrera styrsignalen från joysticken. Det dämpar de skarpaste spikarna i signalen och förhindrar systemet att ta in de snabba handrörelser som kranens acceleration har skapat. / This bachelor thesis was written at Swisslog, who had a problem with the manual control of their high-bay pallet stacker crane. The ride was perceived rough and hard to control at lower speeds.    The main purpose was to examine the source of the phenomenon and how to solve the problem with both software and hardware. It was also requested to investigate ways to lower production costs of the parts of the crane related to the manual control.   The experienced phenomenon is known as biodynamic feedthrough. It refers to the acceleration of the structure affects the body of the operator causing a feedback loop to the input, in this case a joystick. The hand of the operator causes an involuntary control input and making the system unstable and causing an oscillation increasing in amplitude over time. This may be hard or impossible to stop.   The proposed solution is a low-pass filter applied at the output of the joystick. This attenuates the sharpest spikes from the joystick control signal and prevents the system from receiving the fast hand movements caused by the acceleration of the crane.
217

Management of cervical biomechanical dysfunction in schoolboy rugby players using a manual physiotherapy technique / Linda Steyn

Steyn, Linda January 2005 (has links)
Aims: The primary physiotherapeutic aims of the study were to validate a manual physiotherapy evaluation technique in the assessment of cervical biomechanical dysfunction, and to test the effectiveness of a manual physiotherapy treatment technique in the correction of cervical biomechanical dysfunction. The primary educational aims were to test the effectiveness and safety of a therapeutic exercise programme for the correction of biomechanical dysfunction as well as the effectiveness of a neck rehabilitation programme for improving neck muscle strength. Design: A four group experimental design with three pre-test - post-test groups and a control group was used for the investigation. Sample: The subjects were South African schoolboy rugby players between the ages of 15 and 18 years. Groups I and 2 presented with biomechanical dysfunction of their cervical spines, Group 3 had no biomechanical dysfunction of their cervical spines and the players of Group 4, the control group, presented with or without biomechanical dysfunction of their cervical spines. Each group consisted of 25 players. Method: Group I received manual physiotherapy with x-rays before and after treatment. Groups 2 and 3 performed a therapeutic exercise programme, with before and after x-rays, and Group 4 received no intervention between their sets of x-rays. Following the second set of x-rays all the players from Groups I, 2 and 3 performed the neck rehabilitation programme after which a third set of x-rays were taken. Results: The results validated the manual physiotherapy evaluation technique. The manual therapy treatment technique used in the treatment of Group I showed highly significant improvements in cervical biomechanical function. Results for Group 2 following the therapeutic exercise programme showed moderate practically significant improvements in cervical biomechanical dysfunction. The therapeutic exercise programme for the correction of biomechanical dysfunction was found to be very safe with only small significant changes in x-ray measurements (Group 3). The results of the control group showed a negative trend of small statistical significance. A highly significant improvement in cervical circumference as moderate significant improvement in biomechanical function was found following the neck rehabilitation programme. Conclusion: It could therefore be concluded that the manual physiotherapy evaluation technique for motion segment analysis was indeed valid in determining biomechanical dysfunction of the cervical spine. The manual physiotherapy treatment technique as well as the therapeutic exercise programme for the correction of biomechanical dysfunction was found to be effective in the correction of cervical biomechanical dysfunction. It could further be concluded that the therapeutic exercise programme was safe to be performed by players without biomechanical dysfunction. The neck rehabilitation programme was effective in improving cervical circumference as well as cervical biomechanical function. / Thesis (Ph.D. (Education))--North-West University, Potchefstroom Campus, 2005.
218

Comparison between automated and manual DSM pumping projects / R.P. Richter

Richter, Rudolph Petrus January 2008 (has links)
The purpose of this dissertation is to identify the best alternative method of load shifting on clear water pumping systems in the mining industry. This can be done through a comparison analysis between manual and automated Demand Side Management (DSM) projects. The study holds benefits for Eskom and any client wishing to participate in the program. Eskom, by choosing the best method, will ensure sustainable load shifting while the client benefits financially through lower electricity costs. In order to perform this study, research was conducted on the requirements for additional electricity supply in South Africa. Research showed that there is an urgent requirement for additional electricity supply to ensure continued economical growth. DSM was identified as one of the most favourable methods that could be implemented to address the problem. A reason for this is DSM projects are economically viable and can be implemented in a relatively short time. The initiative would also decrease the need for increasing electrical generation capacity. During the research study important information regarding the computation process for load shifting and cost saving performance was gathered. Research was also conducted on the effect of DSM on labour and maintenance cost reduction, as well as economical engineering methods that can be used for alternative selection. The difference in performance between automated and manual systems was compared. The results showed that a 40% improvement of automated systems over manual systems were attainable and sustainable. This will realise a total saving of approximately 45% in electricity costs for the client. Savings in labour and maintenance costs are shown to be achievable through the automation of pumping systems. These saving results were used in the Engineering Economic alternative selection methods where applicable. Economic calculations confirmed that automated projects are the most viable control method. From the comparison study, it is shown that automated controlled systems are more advantageous than manually controlled systems. It will therefore be in the best interest of the client to automate a manually controlled pumping system, as it will result in additional load shifting and cost saving. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.
219

An Essay on the Art of Ingeniously Tormenting for the 21st Century

Thornton, Amber 14 December 2011 (has links)
This satire offers an update of Jane Collier's "An Essay on the Art of Ingeniously Tormenting," an instruction manual for sadists. It includes directions for the beginning tormentor with specific instructions for tormenting strangers, acquaintances, friends, lovers and relatives.
220

Comparison between automated and manual DSM pumping projects / R.P. Richter

Richter, Rudolph Petrus January 2008 (has links)
The purpose of this dissertation is to identify the best alternative method of load shifting on clear water pumping systems in the mining industry. This can be done through a comparison analysis between manual and automated Demand Side Management (DSM) projects. The study holds benefits for Eskom and any client wishing to participate in the program. Eskom, by choosing the best method, will ensure sustainable load shifting while the client benefits financially through lower electricity costs. In order to perform this study, research was conducted on the requirements for additional electricity supply in South Africa. Research showed that there is an urgent requirement for additional electricity supply to ensure continued economical growth. DSM was identified as one of the most favourable methods that could be implemented to address the problem. A reason for this is DSM projects are economically viable and can be implemented in a relatively short time. The initiative would also decrease the need for increasing electrical generation capacity. During the research study important information regarding the computation process for load shifting and cost saving performance was gathered. Research was also conducted on the effect of DSM on labour and maintenance cost reduction, as well as economical engineering methods that can be used for alternative selection. The difference in performance between automated and manual systems was compared. The results showed that a 40% improvement of automated systems over manual systems were attainable and sustainable. This will realise a total saving of approximately 45% in electricity costs for the client. Savings in labour and maintenance costs are shown to be achievable through the automation of pumping systems. These saving results were used in the Engineering Economic alternative selection methods where applicable. Economic calculations confirmed that automated projects are the most viable control method. From the comparison study, it is shown that automated controlled systems are more advantageous than manually controlled systems. It will therefore be in the best interest of the client to automate a manually controlled pumping system, as it will result in additional load shifting and cost saving. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.

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