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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.
1

Tangential Touch Between Free And Fixed Boundaries

Matevosyan, Norayr January 2003 (has links)
No description available.
2

Tangential Touch Between Free And Fixed Boundaries

Matevosyan, Norayr January 2003 (has links)
No description available.
3

The distance from the contact point to the crest of the bone to predict the presence of a black triangle

Cunliffe, Joanne January 2015 (has links)
Losing interdental gingival tissue can lead to a phenomemon known as black triangles. The absence of the interdental papilla (the so called 'black triangle disease') can cause patients problems with appearance, phonetics and with the impaction of food. The gingival soft tissues form the framework and the architecture of the dentition and, in the maxillary anterior region of the mouth, play an important role in dental aesthetics. If there is any change to the shape and/or symmetry of the gingivae through developmental, pathologic or iatrogenic factors, there can be a significant and detrimental change in the appearance and balance of the natural dentition and any prosthetic tooth replacement. In this clinical research study, we find that the radiographic measurement of the distance of the contact point to the crest of the bone is a valid and reliable tool to use. This method also adds strength to predicting black triangles as the results are similar to earlier studies and the numbers used in this study was nearly twice as much.
4

A numerical model for the evaluation of gerotor torque considering multiple contact points and fluid-structure interactions

Mistry, Zubin, Manne, Venkata Harish Babu, Vacca, Andrea, Dautry, Etienne, Petzold, Martin 25 June 2020 (has links)
This paper presents a numerical model for the evaluation of the actual torque in Gerotor units. The model consists of two major modules: the pre-processor module and the HYGESim module. The preprocessor module consists of the geometric and the mechanical module. The geometric pre-processor module considers the CAD geometry of Gerotor with tolerances as input and it provides as output the geometric features needed to evaluate the rotor loading and the flow features. The mechanical preprocessor module evaluates the forces of interaction at the contact points between the rotors. The flow displaced by the unit is evaluated using a lumped parameter model whereas the lubricating gaps are evaluated by solving the Reynolds Equation. The main novel aspects consist of the evaluation of the frictional losses at various interfaces. An Elasto-Hydrodynamic Lubrication (EHL) approach is used to evaluate the frictional losses at the contact points between the rotors. Tests on a prototype Gerotor unit are performed for the model validation, particularly as pertains to the features of the shaft torque. Additionally, the paper comments on the distribution of the different torque loss contributions associated with the operation of the unit taken as reference.
5

A contribuição do sistema âncora em diferentes pontos de contato corporal sobre o controle da postura em idosos / The contribution of the anchor system on different body contact points in the postural control of older adults

Silva, Jair Araujo Lopes da 28 April 2016 (has links)
O aumento no número de idosos nos últimos anos trouxe impactos sociais e econômicos. O processo de envelhecimento e/ou patologias específicas trazem consigo perdas progressivas sensoriais, motoras e de processamento central que estão relacionadas com o aumento das quedas com o avanço da idade. Estas perdas predispõem o idoso a sofrer com limitações físicas de mobilidade, medo de cair ou mesmo sofrer com quedas. Este quadro evoca a necessidade de atenção especial à qualidade de vida dos idosos, com novas intervenções e programas de reabilitação física. Dentre essas novas abordagens para melhorar o funcionamento do controle postural, temos a adição de informação háptica que contribui para reduzir a oscilação corporal durante a manutenção da postura ereta. Uma das formas de adicionar informação háptica ao sistema de controle postural é pelo sistema âncora. Este é uma ferramenta não rígida que consiste de dois cabos maleáveis com 125g de massa repousando no solo e com a outra extremidade segura pelas mãos (âncora tradicional). Considerando que o toque leve em diferentes partes do corpo reduz a oscilação corporal, é possível, da mesma forma, que o uso do sistema âncora em diferentes partes do corpo seja efetivo. Portanto, o objetivo desse estudo foi avaliar o efeito do uso do sistema âncora em diferentes pontos de contato (antebraço e ombro) sobre a oscilação corporal de idosos durante a manutenção da postura ereta Trinta idosos participaram do presente estudo. Eles permaneceram na postura ereta com os pés na posição semi tandem sobre uma plataforma de força para a obtenção do deslocamento do centro de pressão (CP). Cinco condições experimentais foram realizadas: sem âncora, âncora tradicional, âncoras nas mãos fixadas com presilhas, âncoras nos antebraços fixadas com presilhas e âncoras nos ombros fixadas com presilhas. Baseada nos dados fornecidos pelo deslocamento do CP foram calculadas as variáveis: área da elipse, amplitude média de oscilação e velocidade média de oscilação. Os resultados mostraram uma redução da área da elipse e da amplitude média de oscilação na direção anteroposterior nas condições com as âncoras posicionadas nas mãos (tradicional e presilha) e antebraços em comparação a condição sem âncora. Os resultados apontaram ainda uma redução da velocidade média de oscilação na direção anteroposterior na condição de âncoras nos antebraços em comparação a condição sem âncora. Na direção mediolateral, a velocidade média de oscilação reduziu nas condições de âncora fixada nas mãos e antebraços em comparação a condição sem âncora. O uso do sistema âncora na região dos ombros não trouxe redução da oscilação corporal. Em conclusão, o sistema âncora reduziu a oscilação corporal quando o sistema âncora foi posicionado nos antebraços da mesma forma que quando foi fixado/seguro nas mãos. A melhora observada com o uso das âncoras parece não estar relacionada com a quantidade de receptores táteis no ponto de contato dos cabos das âncoras / The increase in the number of older adults in recent years has brought social and economic impacts. The process of aging and/or specific diseases carries progressive sensory, motor and central processing losses that are related to the increased rate of falls with increasing age. These losses predispose the elderly to suffer from physical mobility limitations, fear of falling or even falls. This scenario evokes the need for special attention to the quality of life for older adults, with new interventions and physical rehabilitation programs. Among these new approaches to improve the functioning of the postural control system, we have the addition of haptic information which helps to reduce body sway during maintenance of upright posture. One way to add haptic information to the postural control system is the anchor system. It consists of a non-rigid tool with two flexible cables with 125g mass resting on the ground and with the other end secured by the hands (traditional anchor). Since light touch in different body regions reduces body sway, it is possible, likewise, that the use of the anchor system in different parts of the body to be effective in reducing body sway. Therefore, the aim of this study was to evaluate the effect of using the anchor system in different points of contact (forearm and shoulder) on body sway of older adults during maintenance of upright posture Thirty older adults participated in this study. They stood upright on a force plate to obtain center of pressure displacement (CoP) with their feet in the semi tandem position. Five experimental conditions were carried out: no anchor, traditional anchor, anchors on the hands secured with clasps, anchors on the forearms secured with clasps and anchors on shoulders secured with clasps. Based on data provided by the CP displacement, the following variables were calculated: ellipse area, mean sway amplitude and mean sway velocity. The results showed a reduction in the area of the ellipse and in the mean sway amplitude (anteriorposterior direction) for conditions with anchors hold on the hands and forearms compared to the no anchor condition. The results also indicated a reduction in the mean sway velocity (anterior-posterior direction) with the anchors on the forearms compared to the no anchor condition. For the medial-lateral direction, the mean sway velocity reduced with the anchor on the hands and forearms compared to the no anchor condition. The use of the anchor system in the shoulder region did not reduce body sway. In conclusion, the use of the anchor system reduced body sway when it was placed on the forearms in the same way as when placed/secured on the hands. The improvement observed with the use of anchors does not seem to be related to the amount of tactile receptors in the point of contact of the anchor cables
6

A contribuição do sistema âncora em diferentes pontos de contato corporal sobre o controle da postura em idosos / The contribution of the anchor system on different body contact points in the postural control of older adults

Jair Araujo Lopes da Silva 28 April 2016 (has links)
O aumento no número de idosos nos últimos anos trouxe impactos sociais e econômicos. O processo de envelhecimento e/ou patologias específicas trazem consigo perdas progressivas sensoriais, motoras e de processamento central que estão relacionadas com o aumento das quedas com o avanço da idade. Estas perdas predispõem o idoso a sofrer com limitações físicas de mobilidade, medo de cair ou mesmo sofrer com quedas. Este quadro evoca a necessidade de atenção especial à qualidade de vida dos idosos, com novas intervenções e programas de reabilitação física. Dentre essas novas abordagens para melhorar o funcionamento do controle postural, temos a adição de informação háptica que contribui para reduzir a oscilação corporal durante a manutenção da postura ereta. Uma das formas de adicionar informação háptica ao sistema de controle postural é pelo sistema âncora. Este é uma ferramenta não rígida que consiste de dois cabos maleáveis com 125g de massa repousando no solo e com a outra extremidade segura pelas mãos (âncora tradicional). Considerando que o toque leve em diferentes partes do corpo reduz a oscilação corporal, é possível, da mesma forma, que o uso do sistema âncora em diferentes partes do corpo seja efetivo. Portanto, o objetivo desse estudo foi avaliar o efeito do uso do sistema âncora em diferentes pontos de contato (antebraço e ombro) sobre a oscilação corporal de idosos durante a manutenção da postura ereta Trinta idosos participaram do presente estudo. Eles permaneceram na postura ereta com os pés na posição semi tandem sobre uma plataforma de força para a obtenção do deslocamento do centro de pressão (CP). Cinco condições experimentais foram realizadas: sem âncora, âncora tradicional, âncoras nas mãos fixadas com presilhas, âncoras nos antebraços fixadas com presilhas e âncoras nos ombros fixadas com presilhas. Baseada nos dados fornecidos pelo deslocamento do CP foram calculadas as variáveis: área da elipse, amplitude média de oscilação e velocidade média de oscilação. Os resultados mostraram uma redução da área da elipse e da amplitude média de oscilação na direção anteroposterior nas condições com as âncoras posicionadas nas mãos (tradicional e presilha) e antebraços em comparação a condição sem âncora. Os resultados apontaram ainda uma redução da velocidade média de oscilação na direção anteroposterior na condição de âncoras nos antebraços em comparação a condição sem âncora. Na direção mediolateral, a velocidade média de oscilação reduziu nas condições de âncora fixada nas mãos e antebraços em comparação a condição sem âncora. O uso do sistema âncora na região dos ombros não trouxe redução da oscilação corporal. Em conclusão, o sistema âncora reduziu a oscilação corporal quando o sistema âncora foi posicionado nos antebraços da mesma forma que quando foi fixado/seguro nas mãos. A melhora observada com o uso das âncoras parece não estar relacionada com a quantidade de receptores táteis no ponto de contato dos cabos das âncoras / The increase in the number of older adults in recent years has brought social and economic impacts. The process of aging and/or specific diseases carries progressive sensory, motor and central processing losses that are related to the increased rate of falls with increasing age. These losses predispose the elderly to suffer from physical mobility limitations, fear of falling or even falls. This scenario evokes the need for special attention to the quality of life for older adults, with new interventions and physical rehabilitation programs. Among these new approaches to improve the functioning of the postural control system, we have the addition of haptic information which helps to reduce body sway during maintenance of upright posture. One way to add haptic information to the postural control system is the anchor system. It consists of a non-rigid tool with two flexible cables with 125g mass resting on the ground and with the other end secured by the hands (traditional anchor). Since light touch in different body regions reduces body sway, it is possible, likewise, that the use of the anchor system in different parts of the body to be effective in reducing body sway. Therefore, the aim of this study was to evaluate the effect of using the anchor system in different points of contact (forearm and shoulder) on body sway of older adults during maintenance of upright posture Thirty older adults participated in this study. They stood upright on a force plate to obtain center of pressure displacement (CoP) with their feet in the semi tandem position. Five experimental conditions were carried out: no anchor, traditional anchor, anchors on the hands secured with clasps, anchors on the forearms secured with clasps and anchors on shoulders secured with clasps. Based on data provided by the CP displacement, the following variables were calculated: ellipse area, mean sway amplitude and mean sway velocity. The results showed a reduction in the area of the ellipse and in the mean sway amplitude (anteriorposterior direction) for conditions with anchors hold on the hands and forearms compared to the no anchor condition. The results also indicated a reduction in the mean sway velocity (anterior-posterior direction) with the anchors on the forearms compared to the no anchor condition. For the medial-lateral direction, the mean sway velocity reduced with the anchor on the hands and forearms compared to the no anchor condition. The use of the anchor system in the shoulder region did not reduce body sway. In conclusion, the use of the anchor system reduced body sway when it was placed on the forearms in the same way as when placed/secured on the hands. The improvement observed with the use of anchors does not seem to be related to the amount of tactile receptors in the point of contact of the anchor cables
7

Design and Developement of the testing methodology for the planetary friction drive.

Patial, Rajat Kumar, Singh, Jaspreet January 2020 (has links)
No description available.
8

Autonomous Sensor System for Self-Monitoring of Training in Shooting Sport

Parthasarathy, Sindhu January 2017 (has links)
The factor of precision has always been the mastermind of the shooting sport. With new shooters coming into the field every day and with more aspiring shooters bringing laurels, a help of technology for training can make a difference. When advanced systems like the SCATT, Electronic Target Systems, etc. are marked for the people of the higher background, an easy handle autonomous system for self-monitoring training of precision improvement has always been a question of far reach. This project is about developing an external removable device, which will monitor and evaluate the shooter efficiency of gripping weapon, measure by pressure given at the contact points of the weapon. In the contact points, such as the trigger, the hand grip, cheek rest, butt plate and the hand rest; we use force sensitive resistors, which are connected to an automatic monitoring system built over an Arduino platform. The system analyses the shots based on the variation in the pressure at each point of contact for every shot. By further analysis and consolidation, the average pressure over a range of shots, an optimal pressure point can be fixed individually for the respective shooter. This pressure points are used as references, by rating them in comparison with the corresponding shot acquired in the target. The system includes a pre-designed training program, which autonomously monitors and trains the shooter to achieve the optimum grip in every shot, thereby increasing the accuracy and precision in a sequence of shots. With time, it helps the body to develop a muscle memory based on controlled training and learn the rhythm of applying optimum pressure to achieve better results. / <p>Noted the puBlication content is patented.</p>
9

Poruchy paměti ve stáří / Memory disorders in old age

KROUPOVÁ, Jitka January 2010 (has links)
Memory changes or disorders are typical for old age. The ability to absorb new information, to store it in memory and the subsequent information processing decline in old age. The dividing line between memory impairment and dementia is very vague. Czech Alzheimer Society deals with people affected by dementia. The organisation was launched in June 2008 under a project called Days of memory, project of the early memory disorders detection promotion. The practical part of my thesis deals with the project Days of memory. The first goal of the practical part is to find the reasons why clients suffering from memory disorders seek help at the ČALS contact point {--} the Centre for the Elderly PATUP in ZSF JU. The second aim of the practical part is to compare experiences of the ČALS contact point workers who are involved in the Project of the early memory disorders detection promotion, "Days of Memory", in memory scanning. The data required for the practical part of the thesis were obtained by a combination of a qualitative and quantitative research.
10

Modified train wheel wear calculation for fast calculation / Modifierad tåghjulsförslitning för snabb beräkning

Chen, Shaoyao January 2021 (has links)
In this thesis, a modified wear calculation method is developed to calculate the train wheel wear, which can give less precise but faster results compared to the classic wear calculation method. This modified method is developed based on the classic wear calculation method developed by Jendel, which uses Hertz theory and Kalker’s simplified theory to calculate the contact variables and uses Achard theory to calculate the wear volume in an iterative manner. Compared with the classic method, this modified wear calculation method does not execute the multibody simulation (MBS) at each wear step, instead, it executes MBS by different strategies, for example, does MBS only at the first wear step or does it at every several wear steps. This way, a look-up table is utilised to store the contact variables from MBS and when no MBS is executed, the variables stored in the look-up table would be used to calculate the wear.In order to make the implementation of the modified wear calculation method possible, a contact point detection program is developed in this research. Significantly, this contact point detection program considers the material flexibility and can detect multiple contact points, which makes it very precise. It uses the pressure distribution calculated by Winkler theory as a weighting function to consider the material flexibility. In terms of multiple contact points detection, the gap between wheel and rail is regarded as a function, and the derivative relationship of the function is used to detect multiple contact points. Results from the modified wear calculation method are compared with results from the classic wear calculation method. The effects of different strategies are discussed, and the analysis of the error source is carried out in this work.This modified wear calculation method could be used for predicting the wear condition of the wheel when a quick result with only moderate precision is needed. / I den här avhandlingen utvecklas en modifierad beräkningsmetod för slitage av spårfordons hjul, som ger mindre exakta men snabbare resultat jämfört med den klassiska beräkningsmetoden för hjulslitage. Den modifierade beräkningsmetoden är utvecklad baserat på den klassiska beräkningsmetoden för slitage som utvecklats av Tomas Jendel, som använder Hertz-teorin och Kalkers förenklade teori för att beräkna kontaktvariablerna och använder Achard-teorin för att beräkna volymen av materialet som har slitits bort med en iterativ metod. Jämfört med den klassiska metoden utför inte denna modifierade beräkningsmetod flerkroppssimulering (MBS) vid varje steg där normal hjulprofilen uppdateras, utan använder sig av olika strategier. Till exempel genomförs gör MBS bara vid första slitagesteget eller vid några av slitagestegen. Därför används en uppslagstabell för att lagra kontaktvariablerna från MBS och när ingen MBS exekveras, användas variablerna lagrade i uppslagstabellen för att beräkna slitage.För att möjliggöra implementeringen av den modifierade beräkningsmetoden för slitage utvecklas ett kontaktpunktdetekteringsprogram i denna examensarbete.. Det är viktigt att detekteringsprogrammet tar hänsyn till materialflexibiliteten och att det kan detektera flera kontaktpunkter, med hög precision. Programmet använder Winkler-metoden och den tryckfördelning som beräknas enligt Winkler-teorin som en viktning för att beakta materialets flexibilitet. När det gäller detektering av flera kontaktpunkter betraktas gapet mellan hjul och räls som en funktion, och derivatan av den funktionen används används för att detektera flera kontaktpunkter.Resultat från den modifierade beräkningsmetoden för slitage jämförs med resultaten från den klassiska beräkningsmetoden. Effekterna av olika strategier diskuteras och felkällor analyseras.Denna modifierade beräkningsmetod för slitage kan användas för att förutsäga hjulets slitagetillstånd när ett snabbt resultat med endast måttlig precision behövs.

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