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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.
111

Studie av mobilt integrerat navigationssystem

Kjelsson, Johan January 2007 (has links)
Saab Bofors Dynamics har som huvudsaklig verksamhet att utveckla missiler. Ofta krävs det att någon form av navigationsfunktion byggs in, och eftersom det inte är lätt att testa nya lösningar och algoritmer direkt på missilerna har man tagit fram två autonoma testplattformar, Freke och Gorm, i form av självgående bilar som kan ta sig fram inomhus i t.ex. en korridor. För navigation utomhus lämpar sig GPS väl i många situationer, men i autonoma sammanhang är det inte tillräckligt. GPS är inte alltid tillgänglig på grund av att man inte alltid har fri sikt till minst fyra satelliter och i militära sammanhang är den också lätt att störa ut. Därför förlitar man sig hellre på noggranna tröghetsnavigeringssystem (TNS) som kan ge data i 100-tals Hz, och kompletterar med GPS för att korrigera för avvikelser. Oftast integrerar man sensorerna med någon form av Kalmanfilter för att kunna skatta felparametrar. Om GPS:en faller ifrån kan man med hjälp av felparametrarna navigera noggrannare med ett TNS än man skulle ha gjort annars Noggranna TNS är dock både relativt stora och dyra. Referenssystem kan kosta uppåt en miljon kronor, och lämpar sig alltså varken för engångsbruk (i missiler) eller små billiga autonoma bilar. Nu finns det små och relativt billiga tröghetssensorer (IMU, Inertial Measurement Unit) som storleksmässigt lämpar sig väldigt väl, men som dock har ganska låg noggrannhet. I detta examensarbete görs en studie av två olika navigationsmodeller där en billig IMU och en GPS integreras med hjälp av ett Extended Kalmanfilter (EKF).
112

Pedagogo vadybinės kompetencijos raiška pailgintoje darbo dienos grupėje / Expression of managerial competence of teacher in a group of extended-day activity

Vaikėnienė, Laura 29 June 2009 (has links)
Laura Vaikėnienė. Magistro darbo tema „Pedagogo vadybinės kompetencijos raiška pailgintoje darbo dienos grupėje“. Darbo vadovas doc.dr. M. Gaigalienė. Vilniaus pedagoginis universitetas, Pedagogikos ir psichologijos fakultetas, edukologijos katedra. 2009 . Tyrimo tikslas - ištirti pedagogų vadybinės kompetencijos raišką pailgintoje darbo dienos grupėje. Magistro darbe iškeltas tikslas konkretizuojamas su šiais uždaviniais: išanalizuota ir apibūdinta vadybinės kompetencijos samprata pedagoginėje-psichologinėje literatūroje ir dokumentuose, apžvelgti pailgintos darbo dienos grupės tikslai, uždaviniai ir funkcijos, atskleista vadybinė kompetencijos raiška pailgintos darbo dienos grupės veikloje organizuojant, planuojant, vadovaujant ir kontroliuojant. Remiantis Vyriausybės nutarimais, aptartos visos su nagrinėjama tema susijusios sąvokos, vadovaujantis švietimo sistemos lygių galimybių, kontekstualumo, veiksmingumo, tęstinumo principais, švietimo tikslais ir uždaviniais. Pagal iš anksto susidarytą tyrimų programą buvo atliktas kokybinis ir kiekybinis tyrimas, įgyvendinti iškelti tyrimo programoje tikslai ir uždaviniai, sudaryti struktūrizuoti klausimynas ir interviu. Apklausti aštuoniolika pradinių klasių pedagogai, keturiasdešimt pailgintą darbo dienos grupę lankančių pradinių klasių mokiniai, dvi pailgintos darbo dienos grupės pedagogės ir septyniasdešimt devyni mokinių tėvai. Tyrimo rezultatai rodo, kad vadybinė kompetencija reikalinga ne vien įvairių institucijų vadovams... [toliau žr. visą tekstą] / Laura Vaikėnienė. Theme of the Master‘s thesis ‘Expression of Managerial Competence of Teacher in a Group of Extended-day Activity’. Research supervisor Assoc. Prof. Dr. M. Gaigalienė. Vilnius Pedagogical University, Faculty of Pedagogy and Psychology, Department of Educational Sciences. 2009 . Objective of the research is to make analysis of expression of managerial competence of teacher in a group of extended-day activity. The main objective defined in the Master’s thesis is concretized with the tasks as follows: analysed and described conception of managerial competence in pedagogical-psychological literature and documents, reviewed objectives and functions of a group of extended-day activity, the revealed expression of managerial competence in a group of extended-day activity while organizing, planning, managing and taking control. All concepts related to the theme of the analysis are discussed following the governmental decrees, principles of equal opportunities, contextuality, efficiency, and continuity of educational system, aims and tasks of education. A qualitative and quantitative analysis was made in accordance with made in advance program of research, aims and tasks defined in the research program were fulfilled, a structured questionnaire and interview were prepared. Eighteen primary education teachers, forty primary pupils attending the group of extended-day activity, two extended-day activity teachers and seventy nine parents of pupils responded to... [to full text]
113

Fuzzy Logic and Neural Network-aided Extended Kalman Filter for Mobile Robot Localization

Wei, Zhuo 15 September 2011 (has links)
In this thesis, an algorithm that improves the performance of the extended Kalman filter (EKF) on the mobile robot localization issue is proposed, which is aided by the cooperation of neural network and fuzzy logic. An EKF is used to fuse the information acquired from both the robot optical encoders and the external sensors in order to estimate the current robot position and orientation. Then the error covariance of the EKF is tracked by the covariance matching technique. When the output of the matching technique does not meet the desired condition, a fuzzy logic is employed to adjust the error covariance matrix to modify it back to the desired value range. Since the fuzzy logic is lack of the capability of learning, a neural network is presented in the algorithm to train the EKF. The simulation results demonstrate that, with the comparison to the odometry and the standard EKF method under the same error divergence condition, the proposed extended Kalman filter effectively improves the accuracy of the localization of the mobile robot system and effectively prevents the filter divergence.
114

The Influence of EPS Conditioning Films on Pseudomonas aeruginosa Adhesion to Solid Surfaces

Liang, Jiaming Unknown Date
No description available.
115

The extended empirical likelihood

Wu, Fan 04 May 2015 (has links)
The empirical likelihood method introduced by Owen (1988, 1990) is a powerful nonparametric method for statistical inference. It has been one of the most researched methods in statistics in the last twenty-five years and remains to be a very active area of research today. There is now a large body of literature on empirical likelihood method which covers its applications in many areas of statistics (Owen, 2001). One important problem affecting the empirical likelihood method is its poor accuracy, especially for small sample and/or high-dimension applications. The poor accuracy can be alleviated by using high-order empirical likelihood methods such as the Bartlett corrected empirical likelihood but it cannot be completely resolved by high-order asymptotic methods alone. Since the work of Tsao (2004), the impact of the convex hull constraint in the formulation of the empirical likelihood on the finite sample accuracy has been better understood, and methods have been developed to break this constraint in order to improve the accuracy. Three important methods along this direction are [1] the penalized empirical likelihood of Bartolucci (2007) and Lahiri and Mukhopadhyay (2012), [2] the adjusted empirical likelihood by Chen, Variyath and Abraham (2008), Emerson and Owen (2009), Liu and Chen (2010) and Chen and Huang (2012), and [3] the extended empirical likelihood of Tsao (2013) and Tsao and Wu (2013). The latter is particularly attractive in that it retains not only the asymptotic properties of the original empirical likelihood, but also its important geometric characteristics. In this thesis, we generalize the extended empirical likelihood of Tsao and Wu (2013) to handle inferences in two large classes of one-sample and two-sample problems. In Chapter 2, we generalize the extended empirical likelihood to handle inference for the large class of parameters defined by one-sample estimating equations, which includes the mean as a special case. In Chapters 3 and 4, we generalize the extended empirical likelihood to handle two-sample problems; in Chapter 3, we study the extended empirical likelihood for the difference between two p-dimensional means; in Chapter 4, we consider the extended empirical likelihood for the difference between two p-dimensional parameters defined by estimating equations. In all cases, we give both the first- and second-order extended empirical likelihood methods and compare these methods with existing methods. Technically, the two-sample mean problem in Chapter 3 is a special case of the general two-sample problem in Chapter 4. We single out the mean case to form Chapter 3 not only because it is a standalone published work, but also because it naturally leads up to the more difficult two-sample estimating equations problem in Chapter 4. We note that Chapter 2 is the published paper Tsao and Wu (2014); Chapter 3 is the published paper Wu and Tsao (2014). To comply with the University of Victoria policy regarding the use of published work for thesis and in accordance with copyright agreements between authors and journal publishers, details of these published work are acknowledged at the beginning of these chapters. Chapter 4 is another joint paper Tsao and Wu (2015) which has been submitted for publication. / Graduate / 0463 / fwu@uvic.ca
116

Unimpaired spatial working memory following mammillothalamic tract damage in rats: Implications for the neuroanatomy of memory

Perry, Brook Andrew Leslie January 2012 (has links)
In humans, damage to the mammillothalamic tract (MTT) as a result of localised strokes, tumours or alcohol abuse has consistently been implicated in the severe anterograde amnesia evident in these patients. This small neural pathway, which connects the mammillary bodies (MB) to the anterior thalamic nuclei (ATN), is thought to provide one important link in a larger extended hippocampal circuit involved in encoding and retrieval of episodic memory. Brain damage in clinical cases is, however, typically diffuse and contributions from additional sites of pathology cannot be ruled out. There are also inconsistencies within a limited animal literature on MTT lesions. The current study made MTT lesions in female rats and used multiple „episodic - like‟ memory tasks relevant to the proposed importance of this pathway. The project also intended to test whether enrichment reduces any impairments after MTT lesions. None of the lesions resulted in complete bilateral disconnection of the MTT, but many had moderate to large bilateral (n = 6) (81% to 50%), or unilateral MTT damage (n = 4). Rats with bilateral lesions were compared to controls (n = 14, including 4 other lesion rats in which no lesion occurred). The severe working memory deficit in the water maze expected for rats with MTT lesion was not found and only a slight deficit in reference memory in the water maze was observed (so enrichment was not implemented). Although none of the bilateral MTT lesions were complete, they are also often incomplete in clinical cases and previous research has shown that lesions to the ATN in excess of 50% are sufficient to induce severe behavioural deficits in rats. Therefore, if the MTT is critical to memory then substantial but not total bilateral disconnection should be sufficient to induce profound deficits in rats, at least on spatial working memory. Taken together these findings suggest a less crucial role for the MTT in memory than previously suggested. Future research needs to resolve the inconsistencies observed in the animal literature by repeating the present study, using larger MTT lesions and both male and female rats.
117

Extended Information Matrices for Optimal Designs when the Observations are Correlated II

Pazman, Andrej, Müller, Werner January 1996 (has links) (PDF)
Regression models with correlated errors lead to nonadditivity of the information matrix. This makes the usual approach of design optimization (approximation with a continuous design, application of an equivalence theorem, numerical calculations by a gradient algorithm) impossible. A method is presented that allows the construction of a gradient algorithm by altering the information matrices through adding of supplementary noise. A heuristic is formulated to circumvent the nonconvexity problem and the method is applied to typical examples from the literature. (author's abstract) / Series: Forschungsberichte / Institut für Statistik
118

Whole-Body Motion Planning for Humanoid Robots by Specifying Via-Points

Uno, Yoji, Kagawa, Takahiro, Sung, ChangHyun 07 1900 (has links)
No description available.
119

Road Shape Estimation based on On-board Sensors and Map Data

Foborg, Felix January 2014 (has links)
The ability to acquire accurate information of the surrounding road environment is crucial for autonomous driving and advanced driver assistance systems. A method to estimate the shape of the road has been developed and evaluated. The estimate is based on fusion of data from a road marking detector, a radar tracker, map data, GPS, and inertial sensors. The method is intended for highway use and focus has been on increasing the availability of a sufficiently accurate road shape estimate in the event of sensor failures. To make use of past sensor measurements, an extended Kalman filter has been used together with dynamical models for the road and the ego vehicle. Results from a performance evaluation show that the road shape estimate clearly benefits from being based on a fusion of sensor data. The different sensors have also proven to be of various importance to the different parameters that describe the road shape. / Fordon som kan köra autonomt, det vill säga utan förare, är ett mål för fordonsindustrin och en dröm för många bilägare. Det skulle möjliggöra för förare att använda tiden till annat och minska personalkostnader för transportbolag. Säkerheten på våra vägar skulle även kunna förbättras eftersom att ett sådant system har möjlighet att reagera snabbare än någon människa och drabbas inte av trötthet eller störs av andra passagerare. Förmåga att kunna inhämta och tolka information om den omkringliggande trafiksituationen är ytterst nödvändigt för att kunna utveckla autonoma fordon och behövs även för mer avancerade moderna säkerhetssytem, som till exempel kollissionsvarningssystem. En viktig del i detta är att kunna uppfatta hur formen på vägen ser ut. Målet med detta examensarbete är att utveckla en algoritm som estimerar vägens form baserat på ett antal sensorer monterade på ett fordon och information från en kartdatabas. Den största vikten har legat på att algoritmen alltid ska kunna leverera en tillräckligt bra skattning, även i perioder när sensormätningar inte finns tillgängliga på grund av att sensorer fallerar. Den tänkta miljön är motorvägskörning, främst därför att det innebär en hel del förenklingar i jämförelse med andra typer av vägar. Det stora problemet för sådana algoritmer ligger ofta i att sensorer lider av olika typer av nackdelar. De mäter bara en viss specifik sak, kan ha stora mätfel, är känsliga för olika förhållanden och har begränsingar i räckvidd. För att uttnyttja sensorernas olika styrkor och mildra effekten av deras brister har ett flertal sensorer använts tillsammans. Examensarbetet har utförts på Scania och testats på deras lastbilar. De typer av sensorer som har använts är redan, eller är på god väg att bli, standardutrustning i deras lastbilar och i många andra moderna fordon. Algoritmen använder sig av mätningar från en vägmarkeringsdetektor, som tillhandahåller formen på de två närmaste väglinjerna, en radar, som ger position och rörelse hos framförvarande bilar, en kartdatabas, som tillsammans med en GPS ger tidigare uppmätt kurvatur vid fordonets position, och interna sensorer som mäter det egna fordonets rörelser. För att kunna fortsätta ge en skattning när mätningar inte finns tillgängliga och för att göra algoritmen robustare mot dålig data, har en metod använts som uttnyttjar informationen i tidigare mätvärden, ett så kallat Extended Kalman filter. Denna metod kräver en matematisk beskrivning av hur formen på vägen framför fordonet förväntas förändras över tid, baserat på hur fordonet rör sig. De olika typerna av mätvärden från sensorerna kombineras i metoden och viktas olika beroende på hur tillförlitliga man anser att sensorerna är. Algoritmen har utvärderats på mätningar från allmänna motorvägar utanför Södertälje. Resultatet från denna utvärdering visar att det är väldigt fördelaktigt att kombinera flera olika typer av sensorer för att kunna leverera en bra skattning så ofta som möjligt. Det visar sig även att de olika typerna av sensorer är av olika stor betydelse för olika vägformsparametrar.
120

Standardizing subjectivities: extensions within the field of international education.

Pullman, Ashley 31 August 2011 (has links)
The difficulties non-native-English-speaking students encounter within the field of international education was explored though ethnographic research I conducted on a private Australian accounting college in China. This institute functions within a system and structure of education that has been designed elsewhere – generally for a native-English-speaking learner – under practices of standardization rather than specificity of context. Conflict experienced within everyday practices surrounding discourses of linguistic competences are uprooted to reveal how non-native-English-speaking students are positioned within this field. This positioning requires individuals to follow and recognize a system of learning, acceptable forms of knowledge, and a privileged way of communicating. When previously formed subject positions are individually and/or institutionally deemed in contradiction with this field, conflict within everyday practices arises. While counter-discourses were found within the use of native-languages, they were primarily negatively sanctioned within educational practices leading to further forms of standardization. / Graduate

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