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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.
71

Development, Implementation, And Testing Of A Tightly Coupled Integrated Ins/gps System

Ozturk, Alper 01 January 2003 (has links) (PDF)
This thesis describes the theoretical and practical stages through development to testing of an integrated navigation system, specifically composed of an Inertial Navigation System (INS), and Global Positioning System (GPS). Integrated navigation systems combine the best features of independent systems to bring out increased performance, improved reliability and system integrity. In an integrated INS/GPS system, INS output is used to calculate current navigation states / GPS output is used to supply external measurements, and a Kalman filter is used to provide the most probable corrections to the state estimate using both data. Among various INS/GPS integration strategies, our aim is to construct a tightly coupled integrated INS/GPS system. For this purpose, mathematical models of INS and GPS systems are derived and they are linearized to form system dynamics and system measurement models respectively. A Kalman filter is designed and implemented depending upon these models. Besides these, based on the given aided navigation system representation a quantitative measure for observability is defined using Gramians. Finally, the performance of the developed system is evaluated with real data recorded by the sensors. A comparison with a reference system and also with a loosely coupled system is done to show the superiority of the tightly coupled structure. Scenarios simulating various GPS data outages proved that the tightly coupled system outperformed the loosely coupled system from the aspects of accuracy, reliability and level of observability.
72

The effect of fairness and job satisfaction in the Swedish public sector : Nursing homes in Tierp and Gävle

Arboleda, Yiseth, Bekic, Kenan January 2016 (has links)
Aim: The aim of this study is to analyze how fairness and its´ components; the distributive, procedural and interactional influence job satisfaction in the Swedish Public Sector. Our examination places were nursing homes in two Mid-Swedish towns of Gävle and Tierp.  Method: The study is based on ten qualitative interviews with employees in the nursing homes within the Swedish Public Sector. We used a deductive study approach where we let the participants express themselves at the same time having specific questions derived from theory about fair HRM developed by Bowen, Gilliland and Folger (1999). We analyzed the answers question by question in order to reach to a conclusion and achieve the aim of the study. The data is reported through written text, tables, graphs and findings and implications.  Result & Conclusions: We obtained the following: that there are rules and procedures as well as communications that need to be improved, likewise the gender equality and stand-ins´ possibility to influence. The service quality and delivery is not compromised where the employees experience emotional rewards by final customers. Following issues need to be highlighted; the issue of gender equality, rules and procedures and communications.  Suggestions for future research: A study where a quantitative technique can be used to consider the direct impact between fairness and job satisfaction to check the results of qualitative study and generalize. Further research could also include the impact gender has in predominantly men or women- sectors on perceived fairness and job satisfaction as well as the views of stand-ins on topics as fairness and job satisfaction in public sectors.  Contribution of the thesis: This study contributes to theoretical knowledge development about the notions of fairness and job satisfaction within the Swedish Public Sector. The topics of interest that we recommend managers to improve are: gender equality, rules and procedures and communications at the same time as that the entry- and working conditions should be made better and easier in order to attract younger workforce into the sector.
73

A rela??o entre transtorno da ins?nia e fun??es executivas em adultos

Ferreira, Ol?via Dayse Leite 16 May 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-01-04T19:42:48Z No. of bitstreams: 1 OliviaDayseLeiteFerreira_DISSERT.pdf: 1511253 bytes, checksum: 4b25dc7c6e0792c4bbf24f367f4601f3 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-01-05T19:22:51Z (GMT) No. of bitstreams: 1 OliviaDayseLeiteFerreira_DISSERT.pdf: 1511253 bytes, checksum: 4b25dc7c6e0792c4bbf24f367f4601f3 (MD5) / Made available in DSpace on 2016-01-05T19:22:51Z (GMT). No. of bitstreams: 1 OliviaDayseLeiteFerreira_DISSERT.pdf: 1511253 bytes, checksum: 4b25dc7c6e0792c4bbf24f367f4601f3 (MD5) Previous issue date: 2014-05-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / O transtorno da ins?nia ? definido como uma dificuldade em iniciar ou manter o sono ou acordar antes do esperado e n?o conseguir retornar ao sono, seguido por uma sensa??o de sono n?o reparador e de m? qualidade, presente por pelo menos tr?s meses, com consequ?ncia no funcionamento diurno. Estudos t?m mostrado que o transtorno da ins?nia afeta o funcionamento cognitivo, em especial as fun??es executivas. Entretanto, as pesquisas que buscaram investigar a rela??o entre a ins?nia prim?ria e o funcionamento executivo s?o bastante inconsistentes do ponto de vista metodol?gico, principalmente no que se refere ? variabilidade de m?todos utilizados, ? heterogeneidade de crit?rios de diagn?stico da ins?nia e ao controle do uso de medicamentos que alteram o sono. Neste sentido, a presente pesquisa teve por objetivo investigar a rela??o entre a ins?nia e as fun??es executivas em adultos. Participaram da pesquisa 29 pessoas de ambos os sexos, com idade variando de 20 a 55 anos. Os participantes foram subdivididos em tr?s grupos, sendo um composto por 10 pessoas com ins?nia prim?ria que utilizavam medicamentos para dormir (GIM), nove pessoas com ins?nia prim?ria que n?o utilizava medicamentos (GInM) e 10 pessoas saud?veis que compunham o grupo controle (GC). A pesquisa foi realizada em duas etapas. A primeira envolvia uma avalia??o diagn?stica para o transtorno da ins?nia atrav?s de uma entrevista cl?nica e da aplica??o dos seguintes protocolos: Escala de ins?nia de Atenas, ?ndice de Gravidade da Ins?nia, Di?rio do sono (por 14 dias), ?ndice da Qualidade do Sono de Pittsburgh (IQSP), do Teste de sonol?ncia de Stanford, Invent?rios de depress?o e ansiedade de Beck e o Invent?rio de sintomas de stress para adultos de Lipp. Ap?s esta etapa, foi realizada a avalia??o das fun??es executivas atrav?s da aplica??o de uma bateria de testes neuropsicol?gicos composta pelos testes: Wisconsin, Teste de Stoop, Teste de trilhas Coloridas, Teste da Torre de Londres, Iowa Gambling Task (IGT) e Subteste do WAIS III span d?gitos, que mediram a aten??o seletiva, o controle inibit?rio a flexibilidade cognitiva, o planejamento, a resolu??o de problemas, a tomada de decis?es e a mem?ria operacional, respectivamente. Os resultados mostraram que os insones (GIM e GInM) apresentaram maior lat?ncia do sono, menor dura??o do sono e menor efici?ncia do sono, quando comparados ao GC. No que se refere ao desempenho nas fun??es executivas, n?o se observou diferen?a estatisticamente significativa entre os grupos nas modalidades avaliadas. No entanto, os dados mostram ind?cios de que, comparado ao GInM e GC, o desempenho do GIM se mostrava inferior em tarefas que exigiam respostas r?pidas e mudan?a de foco atencional. J? o GInM, quando comparado ao GIM e GC, exibiu melhor desempenho em tarefas que envolviam a flexibilidade cognitiva. Al?m disso, as medidas do sono prejudicadas foram correlacionadas com o pior desempenho dos insones em todos os componentes avaliados. Conclui-se que as pessoas com o transtorno da ins?nia exibiram desempenho semelhante ao das pessoas saud?veis nos componentes das fun??es executivas. Assim, pode-se inferir que existe uma rela??o estreita entre a ins?nia e as fun??es executivas nos adultos. / The insomnia disorder is defined as a difficulty initiating or maintaining sleep or waking up earlier than expected unable to return to sleep, followed by a feeling of nonrestorative and poor quality sleep, present for at least three months, with consequences on daytime functioning. Studies have shown that insomnia affects cognitive function, especially executive functions. However, researches that sought to investigate the relationship between primary insomnia and executive functioning were quite inconsistent from a methodological point of view, especially in regard to the variability of the used methods, the heterogeneity of diagnostic criteria for insomnia and the control of sleep altering drugs. In this sense, the present study aimed to investigate the relationship between insomnia and executive functions in adults. The participants were 29 people, from both genders, aged 20-55 years old. Participants were divided into three groups, one composed of 10 people with primary insomnia who used sleep medication (GIM), nine people with primary insomnia who did not use medication (GInM) and 10 healthy people who composed the control group (CG). The research was conducted in two stages. The first one involved a diagnostic evaluation for insomnia disorder through a clinical interview and the application of the following protocols: the Athens Insomnia Scale, the Insomnia Severity Index, Sleep Journal (for 14 days), Pittsburgh Sleep Quality Index (PSQI), the Stanford Sleepiness Test, depression and anxiety Beck inventories, and Lipp?s Iventory of stress symptoms for adults. After this stage, the evaluation of executive functions was performed by applying a battery of neuropsychological tests composed by the following tests: Wisconsin, Stoop Test, Colored trails Test, the Tower of London Test, Iowa Gambling Task (IGT) and WAIS III subtest digit span, which measured selective attention, inhibitory control, cognitive flexibility, planning, problem solving, decision making and working memory, respectively. The results showed that insomniacs (GIM and GInM) showed higher sleep latency, shorter sleep duration and lower sleep efficiency compared to the CG. In regard to the performance in executive functions, no statistically significant difference between groups was observed in the evaluated modalities. However, the data show evidence that, compared to GInM and GC, the performance of GIM was lower on tasks that required quick responses and changes in attention focus. On the other hand, GInM, when compared to GIM and GC, showed a better performance on tasks involving cognitive flexibility. Furthermore, impaired sleep measures were correlated with the worst performance of insomniacs in all components evaluated. In conclusion, people with the insomnia disorder showed a performance similar to healthy people?s in components of the executive functioning. Thus, one can infer that there is a relationship between primary insomnia and executive functions in adults.
74

Einfluss des Diabetes mellitus Typ 2 assoziierten Gens CDKAL1 auf die endokrine Funktion pankreatischer Betazellen

Mai, Manuel 06 May 2019 (has links)
Zahlreiche genomweite Assoziationsstudien konnten CDK5 regulatory subunit associated protein 1-like 1 (CDKAL1) als ein Suszeptibilitätsgen für Diabetes mellitus Typ 2 identifizieren. Da die Funktion des Gens noch nicht gänzlich bekannt ist, wurde in der vorliegenden Arbeit der Einfluss von CDKAL1 auf die endokrine Funktion pankreatischer Betazellen untersucht. Dazu wurde in einem Zellkulturmodell mit Ratten-Insulinomzellen (INS-1E), welche zur glukoseabhängigen Insulinausschüttung befähigt sind, CDKAL1 mRNA mittels RNA-Interferenz supprimiert und anschließend eine quantitative Messung des intra- und extrazellulären Insulinproteins und der Insulin mRNA vorgenommen, um eine Aussage über die Sekretion und Expression von Insulin treffen zu können. Die dabei gewonnenen Resultate zeigten, dass CDKAL1 bei Insulinomzellen keinen Einfluss auf die Insulintranskription hat.
75

Orientación espacial de múltiples sensores integrados con constreñimientos geométricos.

Navarro Tarin, Santiago 03 June 2014 (has links)
Las plataformas de georreferenciación de sensores, ya sean aerotransportadas, formando parte de los conocidos vehículos no tripulados (UAV), navales o terrestres, están teniendo mucho interés en los últimos años. La utilización de las técnicas de georreferenciación directa permite reducir los tiempos y optimizar la generación de cartografía y datos de distinta naturaleza espacial. El objetivo de esta Tesis es el desarrollo e implementación de un programa informático capaz de integrar tanto la calibración de los sensores ópticos del sistema fotogramétrico multicámara portátil GNSS/INS, como establecer las relaciones geométricas entre los distintos sensores (ópticos y no ópticos) que conforman el soporte multicámara mediante constreñimientos geométricos. Adicionalmente, se pretende estudiar los distintos comportamientos del sistema multicámara portátil GNSS/INS bajo las condiciones geométricas impuestas, variando el número de puntos de apoyo necesarios para alcanzar una orientación absoluta de máxima calidad y fiabilidad en la orientación espacial de los sensores. El método de ajuste de haces de rayos de un bloque de imágenes se utiliza en la calibración de los sensores que integran el sistema fotogramétrico multicámara portátil GNSS/INS. La georreferenciación mixta con puntos de apoyo dotados de coordenadas UTM está también implementada en el programa. El programa captura las coordenadas de la antena GNSS y la orientación de la IMU en el momento de toma de la imagen, generando lo que se conoce como georrefenciación directa de los sensores ópticos mediante un sistema no acoplado / Navarro Tarin, S. (2014). Orientación espacial de múltiples sensores integrados con constreñimientos geométricos [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/37883 / Alfresco
76

Indoor Geo-location And Tracking Of Mobile Autonomous Robot

Ramamurthy, Mahesh 01 January 2005 (has links)
The field of robotics has always been one of fascination right from the day of Terminator. Even though we still do not have robots that can actually replicate human action and intelligence, progress is being made in the right direction. Robotic applications range from defense to civilian, in public safety and fire fighting. With the increase in urban-warfare robot tracking inside buildings and in cities form a very important application. The numerous applications range from munitions tracking to replacing soldiers for reconnaissance information. Fire fighters use robots for survey of the affected area. Tracking robots has been limited to the local area under consideration. Decision making is inhibited due to limited local knowledge and approximations have to be made. An effective decision making would involve tracking the robot in earth co-ordinates such as latitude and longitude. GPS signal provides us sufficient and reliable data for such decision making. The main drawback of using GPS is that it is unavailable indoors and also there is signal attenuation outdoors. Indoor geolocation forms the basis of tracking robots inside buildings and other places where GPS signals are unavailable. Indoor geolocation has traditionally been the field of wireless networks using techniques such as low frequency RF signals and ultra-wideband antennas. In this thesis we propose a novel method for achieving geolocation and enable tracking. Geolocation and tracking are achieved by a combination of Gyroscope and encoders together referred to as the Inertial Navigation System (INS). Gyroscopes have been widely used in aerospace applications for stabilizing aircrafts. In our case we use gyroscope as means of determining the heading of the robot. Further, commands can be sent to the robot when it is off balance or off-track. Sensors are inherently error prone; hence the process of geolocation is complicated and limited by the imperfect mathematical modeling of input noise. We make use of Kalman Filter for processing erroneous sensor data, as it provides us a robust and stable algorithm. The error characteristics of the sensors are input to the Kalman Filter and filtered data is obtained. We have performed a large set of experiments, both indoors and outdoors to test the reliability of the system. In outdoors we have used the GPS signal to aid the INS measurements. When indoors we utilize the last known position and extrapolate to obtain the GPS co-ordinates.
77

Single Platform Relative Positioning for Sensor Stabilization

Dickman, Jeff 18 July 2008 (has links)
No description available.
78

Integration of Multiple Sensors for Astronaut Navigation on The Lunar Surface

He, Shaojun 06 January 2012 (has links)
No description available.
79

FLUOXETINE: EXAMINING THE SELECTIVE SEROTONIN RE-UPTAKE INHIBITOR’S EFFECTS ON SEROTONIN AND HEDGEHOG SIGNALING IN THE PANCREATIC BETA CELL

Ayyash, Ahmed January 2018 (has links)
Major depressive disorder (MDD) is one of the most common psychiatric illnesses worldwide, with pharmacotherapy as a first-line option for the management of this illness. The National Center for Health Statistics found that the use of antidepressants has increased by more than 4 fold in the last 20 years. While SSRI’s act centrally to treat MDD, their peripheral effects are often overlooked. Interestingly, components of the serotonergic system including the serotonin transporter (SERT), serotonin receptors, and enzymes important for serotonin synthesis (tryptophan hydroxylase 1 and 2; Tph1 and Tph2) are affected by SSRI treatment both centrally and peripherally. This disruption of serotonin signaling in the pancreas is of particular interest as there is a considerable link between the serotonin and hedgehog signaling pathways, both of which are important for pancreatic beta cell function. I hypothesize that pancreatic beta cell exposure to the SSRI fluoxetine in vitro will lead to altered hedgehog signaling ultimately resulting in a disruption in insulin secretion. / Thesis / Master of Science in Medical Sciences (MSMS)
80

A Galerkin Approach to Define Measured Terrain Surfaces with Analytic Basis Vectors to Produce a Compact Representation

Chemistruck, Heather Michelle 03 December 2010 (has links)
The concept of simulation-based engineering has been embraced by virtually every research and industry sector (Sinha, Liang et al. 2001; Mocko and Fenves 2003). Engineering and science communities have become increasingly aware that computer simulation is an indispensable tool for resolving a multitude of scientific and technological problems. It is clearly desirable to gain a reliable perspective on the behaviour of a system early in the design stage, long before building costly prototypes (Chul and Ro 2002; Letherwood, Gunter et al. 2004; Makarand Datar 2007; Ersal, Fathy et al. 2008; Mueller, Ferris et al. 2009). Simulation tools have become a critical part of the automotive industry due to their ability to reduce the time and money spent in the development process. Terrain is the principle source of vertical excitation to the vehicle and must be accurately represented in order to correctly predict the vehicle response in simulation. In this dissertation, non-deformable terrain surfaces are defined as a sequence of vectors, where each vector comprises terrain heights at locations oriented perpendicular to the direction of travel. The evolution and implications of terrain surface measurement techniques and existing methods for correcting INS drift are reviewed as a framework for a new compensation method for INS drift in terrain surface measurements. Each measurement is considered a combination of the true surface and the error surface, defined on a Hilbert vector space, in which the error is decomposed into drift (global error) and noise (local error). It is also desirable to develop a compact, path-specific, terrain surface representation that exploits the inherent anisotropicity in terrain over which vehicles traverse. In order to obtain this, a set of analytic basis vectors is formed from Gegenbauer polynomials, parameterized to approximate the empirical basis vectors of the true terrain surface. It is also desirable to evaluate vehicle models and tire models over a wide range of terrain types, but it is computationally impractical to store long distances of every terrain surface variation. This dissertation examines the terrain surface, rather than the terrain profile, to maximize the information available to the tire model (i.e. wheel path data). A method to decompose the terrain surface as a combination of deterministic and stochastic components is also developed. / Ph. D.

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