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Posição dos terceiros molares na má oclusão de Classe II, subdivisão / THIRD MOLAR POSITION IN CLASS II, SUBDIVISION MALOCCLUSIONCruz, Karina Santana 11 February 2004 (has links)
Este trabalho objetivou comparar os espaços destinados à irrupção dos terceiros molares superiores e inferiores, e suas angulações, de ambos os lados, na má oclusão de Classe II, subdivisão. A amostra foi composta de um grupo experimental (grupo 1) contendo 29 pacientes, com más oclusões de Classe II, subdivisão, apresentando relação dos molares de Classe II completa de um lado e Classe I do outro lado, sendo 17 do gênero masculino e 12 do feminino, com média de idade de 14,73 anos. Dois subgrupos foram classificados dentre o total de casos do grupo 1, de acordo com duas etiologias da Classe II, subdivisão: subgrupo Tipo 1 (18 casos) caracterizado pela coincidência da linha média dentária superior em relação ao plano sagital mediano e desvio da linha média inferior em direção ao lado da Classe II. O subgrupo Tipo 2 (6 casos) apresentava coincidência da linha média dentária inferior em relação ao plano sagital mediano e desvio da linha média dentária superior em sentido contrário ao lado da Classe II. O grupo controle de oclusão normal (grupo 2) constituiu-se de 17 pacientes, sendo 11 do gênero feminino e seis do masculino, com média de idade de 21,73 anos. Foram obtidas quatro radiografias: uma submentoniana, duas oblíquas corrigidas (lados direito e esquerdo) e uma panorâmica dos 46 participantes desta pesquisa. Os testes t pareados de Student foram empregados nas comparações entre os lados de cada grupo e subgrupos, individualmente. Foram realizados os testes t independentes para as comparações das assimetrias lineares e angulares do espaço e das angulações dos terceiros molares do grupo e subgrupos experimentais com o grupo controle. Os resultados demonstraram que houve diferenças nos espaços disponíveis superior e inferior e nas angulações dos terceiros molares inferiores entre os lados de Classe I e de Classe II, na má oclusão de Classe II, subdivisão. No subgrupo Tipo 1, os espaços disponíveis para os terceiros molares superiores e inferiores e as angulações dos terceiros molares inferiores refletiram as características do posicionamento dentoalveolar em suas bases apicais nesse tipo de má oclusão. No subgrupo Tipo 2, os espaços disponíveis para os terceiros molares superiores e suas angulações tenderam a refletir as características assimétricas dentoalveolares deste grupo. / The purpose of this research was to compare the available space and inclination of the mandibular and maxillary third molars between the Class I and Class II sides in subjects presenting Class II, subdivision malocclusions. An experimental group of 29 Class II, subdivision patients (17 males and 12 females) with a mean age of 14.73 years and a normal occlusion control group of 17 patients (11 females and 6 males) with a mean age of 21.73 years were used in this study. Two subgroups were selected among the total subdivision group according to the two different etiologies: Type 1 subgroup (18 cases) presented a coincidence of the maxillary dental midline with the facial midline and a deviation of the mandibular dental midline. Type 2 subgroup (6 cases) presented deviation of maxillary midline and coincidence of mandibular midline with the facial midline. One submentovertex, two obliques and one panoramic radiograph were taken from each of the 46 subjects of the groups. Dependent t tests were used to compare the available space and the third molar angular measurements of both sides among each group and subgroups individually. Independent t tests were used to compare the linear and angular asymmetries of the available space and angulation of the third molars between the experimental and the control groups. Results demonstrated that there were differences between the Class I and the Class II sides in the available space for the maxillary and mandibular third molars and in the angulation of the mandibular third molars in Class II subdivision malocclusions. In Type 1 Class II subdivision malocclusions the available maxillary and mandibular spaces and the mandibular third molar angulation reflected their characteristic dentoalveolar positioning in their apical bases in this type of malocclusion. In Type 2 Class II subdivision malocclusions the available maxillary and mandibular spaces and the mandibular third molar angulation tended to reflect their characteristic dentoalveolar positioning in their apical bases in this type of malocclusion.
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Online Calibration of Camera Roll Angle / Dynamisk kalibrering av kamerarollvinkelnde Laval, Astrid January 2013 (has links)
Modern day cars are often equipped with a vision system that collects informa- tion about the car and its surroundings. Camera calibration is extremely impor- tant in order to maintain high accuracy in an automotive safety applications. The cameras are calibrated offline in the factory, however the mounting of the camera may change slowly over time. If the angles of the actual mounting of the cam- era are known compensation for the angles can be done in software. Therefore, online calibration is desirable. This master’s thesis describes how to dynamically calibrate the roll angle. Two different methods have been implemented and compared.The first detects verti- cal edges in the image, such as houses and lamp posts. The second one method detects license plates on other cars in front of the camera in order to calculate the roll angle. The two methods are evaluated and the results are discussed. The results of the methods are very varied, and the method that turned out to give the best results was the one that detects vertical edges.
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The Influence of Q-Angle and Gender on the Stair-Climbing Kinetics and Kinematics of the KneeCartwright, Alexis Marion 21 September 2007 (has links)
Background: Knee joint motion and quadriceps activity play a crucial role in all lower limb tasks, especially those which are highly dynamic and weight-bearing. Due to anatomical differences between men and women such as height, leg length, and hip width, alignment and mechanics of the lower limb are different between males and females. An anatomical variable which is associated with alignment in the lower limb is the quadriceps muscle angle (q-angle).
The purpose of this study is to determine if there is a relationship between q-angle, activity of the quadriceps and hamstring muscles and the kinetics and kinematics of the knee during stairclimbing. An investigation on the reliability of q-angle measurements was also made prior to the
primary study.
Methods: To test the interclass reliability of q-angle measurements, three individuals measured the q-angle on 20 subjects. The primary researcher measured the same twenty individuals on three separate days to determine intra-rater reliability.
The primary study involved 10 male and 10 female subjects completing 20 stair-climbing trials (10 ascent, 10 descent). Kinematic and kinetic data were collected on the lower limbs as well as electromyography (EMG) on two quadriceps muscles and one hamstring muscle. Knee joint peak and occurrence of peak moments, average EMG amplitude and peak and occurrence of peak EMG were analyzed by gender and high and low q-angle. A two way analysis of variance (ANOVA) was used to test the statistical significance of each measured variable (alpha = 0.05).
Results & Discussion: The inter-rater reliability for q-angle was low (0.27-0.78) but the intrarater reliability showed q-angle measurements to be very reliable (0.80-0.95). For study 2, it was found that females had increased vastus lateralis and vastus medialis peak EMG and average EMG amplitudes for stair ascent and descent compared to males. Furthermore, for descent only, females demonstrated having delayed occurrence of peak EMG for vastus lateralis and biceps femoris, and exhibited an increased peak knee extension moment and a decreased peak knee adduction moment compared to males. For q-angle, there was a significant difference found for biceps femoris occurrence of peak EMG during descent, with the high q-angle group having
delayed occurrence of peak. For ascent, the high q-angle group had significantly increased average vastus lateralis EMG and an earlier occurrence of knee abduction moment. Q-angles were found to be higher for women compared to men.
Conclusion: This study confirms that gender differences do exist in knee moment and thigh
EMG parameters with stair ascent and stair descent. With the high incidence of significant findings for the quadriceps muscle, further investigation is warranted to determine if a relationship does exist between q-angle and knee joint function. It would also be recommended that hip mechanics be included in future studies due to the difference seen in adduction moments at the knee.
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GPS/INS Combination for a Beam Tracking SystemZhang, Sheng January 2011 (has links)
In recent years, Land vehicle navigation system (LVNS) technology is a subject of great interest due to its potential for both consumer and business vehicle markets. GPS/INS ( Global Positioning System/ Inertial Navigation System ) integrated system is an effective solution to realize the LVNS. And how to keep communication between the vehicle and satellite while the vehicle is running in a bad environment is the main task in this thesis. The thesis provides an introduction to beam tracking system and two algorithms of how to improve the performance, then compare these two algorithms and choose the suitable one and implement it on ArduPilotMega board using Arduino language, at last test the integrated GPS/INS system in practice in order to estimate the performance. The requirements of the project are the maximum angular speed and angular acceleration speed of the vehicle are and , respectively. Two algorithms which are Direction Cosine Matrix (DCM) and Euler Angle are evaluated in the system. In this thesis, there are many rotations due to the hostile environment, and DCM algorithm is not suitable for the requirement according to the results of simulation. Therefore, an innovated method which is Euler Angle Algorithm can be one effective way to solve the probelm. The primary idea of Euler Angle algorithm is to calculate the difference between the reference direction vector and the measurement direction vector from GPS and accelerometers, once there is an error rotation, take the cross product and rotate the incorrect direction vector back to original direction. The simulation results show that by implementing EA algorithm, system requirements can be achievable with a 10kHz update rate antenna and a 4000Hz sampling rate gyroscope, also with EA implementation in ArduPilotMega board, the real system tracking ability can be enhanced effectively.
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The Influence of Q-Angle and Gender on the Stair-Climbing Kinetics and Kinematics of the KneeCartwright, Alexis Marion 21 September 2007 (has links)
Background: Knee joint motion and quadriceps activity play a crucial role in all lower limb tasks, especially those which are highly dynamic and weight-bearing. Due to anatomical differences between men and women such as height, leg length, and hip width, alignment and mechanics of the lower limb are different between males and females. An anatomical variable which is associated with alignment in the lower limb is the quadriceps muscle angle (q-angle).
The purpose of this study is to determine if there is a relationship between q-angle, activity of the quadriceps and hamstring muscles and the kinetics and kinematics of the knee during stairclimbing. An investigation on the reliability of q-angle measurements was also made prior to the
primary study.
Methods: To test the interclass reliability of q-angle measurements, three individuals measured the q-angle on 20 subjects. The primary researcher measured the same twenty individuals on three separate days to determine intra-rater reliability.
The primary study involved 10 male and 10 female subjects completing 20 stair-climbing trials (10 ascent, 10 descent). Kinematic and kinetic data were collected on the lower limbs as well as electromyography (EMG) on two quadriceps muscles and one hamstring muscle. Knee joint peak and occurrence of peak moments, average EMG amplitude and peak and occurrence of peak EMG were analyzed by gender and high and low q-angle. A two way analysis of variance (ANOVA) was used to test the statistical significance of each measured variable (alpha = 0.05).
Results & Discussion: The inter-rater reliability for q-angle was low (0.27-0.78) but the intrarater reliability showed q-angle measurements to be very reliable (0.80-0.95). For study 2, it was found that females had increased vastus lateralis and vastus medialis peak EMG and average EMG amplitudes for stair ascent and descent compared to males. Furthermore, for descent only, females demonstrated having delayed occurrence of peak EMG for vastus lateralis and biceps femoris, and exhibited an increased peak knee extension moment and a decreased peak knee adduction moment compared to males. For q-angle, there was a significant difference found for biceps femoris occurrence of peak EMG during descent, with the high q-angle group having
delayed occurrence of peak. For ascent, the high q-angle group had significantly increased average vastus lateralis EMG and an earlier occurrence of knee abduction moment. Q-angles were found to be higher for women compared to men.
Conclusion: This study confirms that gender differences do exist in knee moment and thigh
EMG parameters with stair ascent and stair descent. With the high incidence of significant findings for the quadriceps muscle, further investigation is warranted to determine if a relationship does exist between q-angle and knee joint function. It would also be recommended that hip mechanics be included in future studies due to the difference seen in adduction moments at the knee.
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The Growth Mechanism of Inclined AlN Films and Fabrication of Dual Mode Solidly Mounted ResonatorsChen, Cheng-ting 02 August 2010 (has links)
The 1/4£f dual-mode resonators made from c-axis-oriented aluminum nitride films grown on different conduction material have been studied in this thesis. The RF/DC sputter system is used to grow on layers of reflector. During the porcess, 3.5 pairs of Bragg reflector alternating with W and SiO2 are composed by Si substractor. To achieve 0.999 reflective rate, fabrication parameters are adjusted to make W films become £\-phase structurre. On the other hand, piezoelectric layers as well as reflective layers that using reactive RF magnetron sputtering system and means of off-axis are combined to deposite optimal resonators of shear mode quality factor (Q) resonatros. While changing the substract and target distance between various bottom electrode materials, including Si, W/Si, and Mo/Si could deposit AlN with various c-axis tilting angle which resulted in stimulating longitudinal and shear acoustic waves. Futhermore, the finding is used to discuss the growth mechanism of inclined AlN by TEM.
The analysis of various distances of AlN films shows that column inclining angle and XRD-Rocking Curve £s will increase with distance. The quality of shear mode would be better when column and £s are highly shifed.
About the influence on AlN deposites, AlN/Si was grown away from the center by 6 cm. AlN/Si column inclining angle is about 20 degree, and RMS could reach 2.63nm beneath. Uner AlN/W/Si, column incling angle is about 30 degree, and £s shift angle 4.14 degree, the shear mode quality factor of freaquency response is obtained to 262. Under AlN/Mo/W/Si, column incling angle would be 25.4 degree, and XRD are better-choosed c-aixsm, £s tilting angle shifs 6.72 degree, and the shear mode quality factor is obtained to 290. Film intersurface appears bigger misfit by TEM to obtain better shear mode.
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Studies of electro-optical properties of twisted-nematic liquid crystals at oblique viewing directions and their applicationsHe, Ming-li 05 August 2010 (has links)
This study investigates the optical properties of the twisted-nematic liquid-crystals at oblique directions and their applications. A large difference in the phase retardation and the twisted angle of the TN-LC from different viewing directions occurs at the low voltage regime. The proposed viewing angle switching (VAS) panel is developed using this large optically anisotropic behavior of the TN-LC. The proposed VAS panel is only perceived clearly at normal and downward directions in a narrow viewing angle mode to ensure high privacy protection, it highly promising for mobile device applications.
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Viewing angle switchable displays based on three-dimension control of liquid-crystal orientationChen, Chia-Wei 08 September 2010 (has links)
In this study, a liquid-crystal display (LCD) with the capability of switchable viewing-angle is proposed. The contrast ratio of the LCD mainly depends on the transmittance of the bright state and the dark state. By using the improved structure of the pixel electrodes, the viewing angle of the LCD can be switched between the wide viewing-angle mode and the narrow-viewing angle mode. Based on the proposed three-electrode structure, the liquid-crystal orientation of the LCD is controlled to generate different light-leakage conditions at large viewing angles, thus, resulting in the switch of the viewing angle of the LCD. The proposed structure, which has the slim outline and low-cost of the LCD, is a simple way to control the viewing angle of the LCD. Potential applications for the protection of personal privacy are emphasized.
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Attitude Stabilization of an Aircraft via Nonlinear Optimal Control Based on Aerodynamic DataTakahama, Morio, Sakamoto, Noboru, Yamato, Yuhei 08 1900 (has links)
No description available.
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The Design of A New Type Steering Machanism For WheelchairsLuo, Kuang-Hong 22 June 2003 (has links)
It¡¦s easy to get the complication of shoulder by using the traditional type of driving a wheelchair, and the move speed of a wheelchair is upper with motor-driven, so makes shimmy or slide usually appearing on caster when the wheelchair is steering .On the other hand, the drive mechanism of wheelchair by single-wheel was developed by the members of MEVL at the same time that this paper was written. Because of these reasons above, this paper analyze the type of steering mechanism and the patents of wheelchair¡¦s steering mechanism first, secondly find the fittest steering mechanism type for a wheelchair. Furthermore, this paper also discusses some irregular conditions of a caster and theirs reasons and how to prove them when a wheelchair is steering or moving with high speed by using several simpler mode of mechanics, such as caster shimmy, the slip angle of a caster, and some irregular cases when wheelchair is driven by single wheel. Finally this paper will design a new type steering mechanism for wheelchair by applied the results of research that above-mentioned, this new steering mechanism not only improve the traditional steering mode of a wheelchair, also avoid several irregular condition above occurring in the caster, moreover, it can be enabled or disabled by user anytime. So this paper expects that the performance of a wheelchair will be raised after the new type steering mechanism is designed.
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