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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.
31

Diversity and Ecology of a Middle Campanian (Late Cretaceous) Marine Reptile Assemblage from Skåne, Southern Sweden / Diversitet och ekologi hos en ansamling marina reptiler från mellersta Campanian (Yngre Krita) från Skåne

Källsten, Lena January 2015 (has links)
This study has looked at an assemblage of fossilised teeth from Mesozoic marine amniotes from the Kristianstad basin in southern Sweden in order to make an estimate of the ecomorph diversity within said assemblage through looking at the morphology of the teeth. This was done as a pilot study to see if further studies would be able to produce worthwhile results. The assemblage consists largely of isolated tooth crowns, mostly from small- to medium sized mosasaurs such as Clidastes and Eonatator, but also contains larger mosasaurs, as well as a couple of plesiosaurs and one species of a marine crocodile. The analysis was performed on images of teeth using software developed for use in morphometrics. The resulting graphs imply a division into three guilds; the first represented by the short and blunt teeth of the crocodilian, the second by the elongated teeth of the plesiosaurs, and the third by the knife-like teeth of the mosasaurs. Since the mosasaurs overlap to a high degree in tooth shape, but also show quite diversity in size, it is possible the main dividing factor would have been size rather than type of prey. Further studies would be able to get a more accurate image of the ecology of this fauna by increasing the number of specimen in the analysis as well as taking into consideration more factors from other studies of similar taxa, such as jaw sizes, bite marks and gut contents. / Det här arbetet har studerat fossila tänder tillhörande Mesozoiska marina amnioter från Kristianstadsbassängen i södra Sverige, med avsikt att göra en uppskattning av den ekomorfa spridningen inom gruppen genom att studera tändernas form. Detta är enbart en pilotstudie för att se om fortsatta studier kan ge givande resultat. Det studerade materialet är en del av en samling till stor del bestående av enbart lösa tandkronor, mest från små till medelstora mosasaurier, såsom Clidastes och Eonatator, men även från större mosasaurier, så väl som ett par plesiosaurier och en marin krokodil-art. För analysen användes en programvara specifikt utvecklad för morfometri. De resulterande graferna antyder en indelning i tre “gillen”; det första representeras av de korta och trubbiga tänderna tillhörande krokodilen, det andra av de långsmala tänderna hos plesiosaurierna, och det tredje av de knivlika mosasaurietänderna. Eftersom mosasaurierna överlappar till stor grad gällande formen på tänderna, men skiljer sig mycket åt i storlek, så är det troligt att det snarare var storleken på bytesdjuren, och inte vilken typ, som skiljde dem åt. Framtida studier skulle kunna ge en bättre bild av den här faunans ekosystem dels genom att inkludera fler exemplar i analysen, och dels genom att inkludera andra faktorer från studier av liknande taxa, såsom käkstorlek, bitmärken och maginnehåll.
32

3D pose estimation of flying animals in multi-view video datasets

Breslav, Mikhail 04 December 2016 (has links)
Flying animals such as bats, birds, and moths are actively studied by researchers wanting to better understand these animals’ behavior and flight characteristics. Towards this goal, multi-view videos of flying animals have been recorded both in lab- oratory conditions and natural habitats. The analysis of these videos has shifted over time from manual inspection by scientists to more automated and quantitative approaches based on computer vision algorithms. This thesis describes a study on the largely unexplored problem of 3D pose estimation of flying animals in multi-view video data. This problem has received little attention in the computer vision community where few flying animal datasets exist. Additionally, published solutions from researchers in the natural sciences have not taken full advantage of advancements in computer vision research. This thesis addresses this gap by proposing three different approaches for 3D pose estimation of flying animals in multi-view video datasets, which evolve from successful pose estimation paradigms used in computer vision. The first approach models the appearance of a flying animal with a synthetic 3D graphics model and then uses a Markov Random Field to model 3D pose estimation over time as a single optimization problem. The second approach builds on the success of Pictorial Structures models and further improves them for the case where only a sparse set of landmarks are annotated in training data. The proposed approach first discovers parts from regions of the training images that are not annotated. The discovered parts are then used to generate more accurate appearance likelihood terms which in turn produce more accurate landmark localizations. The third approach takes advantage of the success of deep learning models and adapts existing deep architectures to perform landmark localization. Both the second and third approaches perform 3D pose estimation by first obtaining accurate localization of key landmarks in individual views, and then using calibrated cameras and camera geometry to reconstruct the 3D position of key landmarks. This thesis shows that the proposed algorithms generate first-of-a-kind and leading results on real world datasets of bats and moths, respectively. Furthermore, a variety of resources are made freely available to the public to further strengthen the connection between research communities.
33

Comparison of pain relief and functional improvement in landmark vs. ultrasound-guided corticosteroid injections for adhesive capsulitis: a prospective study

Coene, Ryan Patrick 12 July 2017 (has links)
BACKGROUND: Adhesive capsulitis is an idiopathic disorder of the shoulder that is characterized by pain in combination with the gradual loss of passive and active range of motion. It is typically self-limiting, although the disease still remains poorly understood. However, there are several treatment modalities, both conservative and surgical, that provide significant clinical benefit for patients with adhesive capsulitis. Corticosteroid injections are an established conservative treatment method for adhesive capsulitis. Several studies have demonstrated that injections provide short-term benefits in terms of shoulder mobility and pain reduction. The intra-articular injections can be performed blindly (landmark) or with ultrasound (US) guidance. Physicians administer injections under US guidance in an attempt to improve the accuracy of the injection. However, it remains unclear whether US-guided injections relieve symptoms of adhesive capsulitis more effectively than landmark injections. OBJECTIVE: To compare the pain relief, self-reported function, and shoulder range of motion (ROM) outcomes of landmark versus US-guided corticosteroid injections for adhesive capsulitis. Methods: A total of 21 patients with adhesive capsulitis were randomized to receive either a landmark or US-guided intra-articular corticosteroid injection. Clinical outcome measures were documented at baseline, 6 weeks, and 12 weeks. These measures included a visual analog scale (VAS) for pain, the Single Assessment Numeric Evaluation (SANE) score for self-reported function, and passive shoulder ROM, including forward flexion, external rotation, and abduction. RESULTS: Both US-guided and landmark glenohumeral (GH) joint injections significantly improved VAS scores, SANE scores, and shoulder ROM outcomes. Improvement was maintained for all outcome measures in both groups throughout the 12 week treatment period. However, there were no significant differences seen in outcome measures between the two groups except that US-guided provided greater improvement in abduction at the 6 week follow-up (P = .004). CONCLUSIONS: This preliminary report found that there is no significant difference in the effectiveness of US-guided and landmark cortisone injection in terms of pain improvement, self-reported functions, and ROM outcomes for adhesive capsulitis.
34

Driver's Gaze Zone Estimation in Realistic Driving Environment by Kinect

Luo, Chong 07 September 2018 (has links)
Driver's distraction is one of the main areas, which researchers are focusing on, in design of Advanced Drivers Assistance Systems (ADASs). Head pose and eye-gaze direction are two reliable indicators of a driver's gaze and the current focus of attention. Compared with other methods that make use of head pose only, methods that combine eye information can achieve higher accuracy. The naturalistic driving environment always presents unique challenges (e.g., unstable illumination, jolts, etc.) to video-based gaze estimation and tracking systems. Some methods can achieve relatively high proficiency in the stationary laboratory environment, but they may not be suitable for the unstable driving environment. In addition, performing in real time or near-real time is another consideration for gaze estimation in an ADAS. Therefore, these special challenges need to be overcome to design ADASs. In this thesis, we proposed a new driver's gaze zone estimation framework designed for the naturalistic driving environment. The framework combines head and eye information to estimate the gaze zone of the driver in both daytime and nighttime. The framework is composed of five main components: Facial Landmark Detection, Head Pose Estimation, Iris Center Detection, Upper Eyelid Information Extraction, and Gaze Zone Estimation. First, Constrained Local Neural Field (CLNF) is applied to obtain the facial landmarks in the image plane and the 3D model of the face in the object frame. In addition, extracting region of interest (ROI) is utilized as an optimization strategy for CLNF facial landmark detection. Second, head pose estimation can be regarded as a Perspective-n-Point (PnP) problem. Levenberg-Marquardt optimization method is used to solve the PnP problem based on the 2D landmark locations in the image plane and their corresponding 3D locations in the object frame. Third, a regression model-based method is employed to obtain the iris center from eye landmarks detected in the previous part. For upper eyelid information extraction, a quadratic function is utilized to model the upper eyelid, and the second-order coefficient is extracted. Finally, the head pose and the eye information are combined to form a feature vector, and Random Decision Forest classifier is utilized to estimate the current gaze zone of the driver from the feature vector extracted. The experiment is carried out in the realistic driving environment in both daytime and nighttime with three volunteers by Kinect sensor V2 for Windows that is put at the back of windshield. Weighted and unweighted accuracy are utilized as evaluation metrics in gaze zone estimation. Weighted accuracy evaluates gaze zones with different significance while unweighted accuracy treats each gaze zone equally. Experiment results show that the gaze zone estimation framework proposed in this work has better performance compared to the reference in the daytime. The weighted and unweighted accuracy of gaze zone estimation reach 96.6% and 95.0% for daytime, respectively. For nighttime, the weighted and unweighted accuracy can reach 96% and 91.4%.
35

"Estudo da padronização para a determinação de pontos cefalométricos utilizados na cefalometria radiológica" / Standardization for the determination of cephalometric landmarks used in radiological cephalometric analysis

Mustaphá Amad Neto 06 October 2004 (has links)
O objetivo nesta pesquisa foi o de avaliar quantitativamente as variações na determinação de 7 pontos cefalométricos e analisar o quanto que estes erros podem influenciar no planejamento e progressão da terapêutica ortodôntica. Foram utilizados 14 crânios macerados onde fora colocadas esferas metálicas para a demarcação dos pontos cefalométricos escolhidos. Estes crânios foram radiografados com e sem as esferas metálicas, e as grandezas cefalométricas avaliadas estatisticamente. Os resultados mostraram que a média de erro na localização dos pontos foi de 57,5% e que este desvio em termos numéricos podem levar a equívocos de planejamento que podem comprometer seriamente o resultado do tratamento com desvios em algumas medidas cefalométricas de até 4mm. As mensurações relacionadas aos pontos espinha nasal anterior, pogonio e gônio foram as que tiveram maior reprodutibilidade, porém, as medidas cefalométricas relacionadas ao ponto A mostraram que as diferenças encontradas então em torno de 4,3mm, e que a avaliação do comprimento mandibular obtida pela localização do ponto condílio, também gerou diferenças de 2,8mm em média, alterando assim substancialmente as avaliações para diagnóstico e tratamento ortodôntico e cirúrgico. / The aim of this study were to evaluate quantitatively the variations on the determination of 7 cephalometric landmarks and to analyze how these differences may influence the planning and outcome of the orthodontic treatment. Small steel balls were glued on specific sites of 14 dry skulls to represent the true anatomical landmarks. The skulls were radiographed with and without the steel balls, and the cephalometric values were submitted to statistical analysis. Results showed that the error in the localization of the landmarks was in average 57,5%. This high deviation, that reaches up to 4mm in certain cephalometric measurements, could lead to errors in treatment planning and compromise the result of any orthodontic treatment. Measurements of the Anterior Nasal Spine, Pogonion and Gonion showed the highest reproducibility, while point A showed the lowest (4,3mm). The evaluation of the mandibular length through the identification of Condyle also showed high discrepancies (2,8mm), which may alter the evaluations for orthodontic and/or surgical diagnosis and treatment.
36

"A influência do controle de qualidade em telerradiografias em norma lateral e na obtenção de pontos cefalométricos" / The influence of quality control on lateral cephalographs and on cephalometric landmarks

Ana Lucia Tolazzi 19 October 2005 (has links)
Os objetivos deste estudo foram: 1- avaliar a influência dos fatores energéticos e da posição de cabeça, no sentido vertical e horizontal, na qualidade das radiografias cefalométricas e na interpretação dos resultados para diagnóstico e plano de tratamento; 2- verificar as implicações oriundas da determinação de pontos cefalométricos equivocados pela falha no controle de qualidade nas radiografias cefalométricas. Telerradiografias em norma lateral, padronizadas em condições reprodutíveis, foram realizadas em um crânio seco e em um fantoma. Realizou-se simulações de falhas técnicas relacionadas a quilovoltagem, miliamperagem, tempo de exposição e posição do filtro de alumínio, e a modificações horizontais e verticais de 3º, 6º, e 9º do fantoma em relação ao plano sagital mediano e ao plano de Frankfurt, respectivamente. Vinte e seis radiografias cefalométricas foram selecionadas e encaminhadas para seis examinadores (3 ortodontistas e 3 radiologistas), para executarem manualmente a análise cefalométrica de McNamara. ANOVA comparou as medidas de onze variáveis nas 26 análises cefalométricas. Quando ocorreu diferença, aplicou-se o teste de comparações múltiplas de Games-Howell (variâncias heterogêneas) e o de Tukey HSD (variâncias homogêneas), ao nível de probabilidade 5%. Não houve diferenças estatisticamente significantes entre os seis examinadores e entre as onze variáveis estudadas (p > 0,05). Observou-se pouca influência dos fatores energéticos na qualidade das imagens e reprodutibilidade dos pontos cefalométricos estudados. As variações horizontais da posição da cabeça em relação ao plano sagital mediano apresentaram discrepâncias significativas na qualidade da imagem radiográfica para cefalometria. Pontos cefalométricos inadequados comprometeram o diagnóstico, mesmo com examinadores experientes. A interpretação das cefalometrias precisa estar associada com aspectos clínicos, fotografias, modelos gnatostáticos e outras radiografias, para estabelecer o diagnóstico e plano de tratamento. / The aims of this study were to evaluate the influence of energetic factors and head position on the quality of cephalometric radiographs and on their interpretation, and to analyze the consequences of incorrect landmark identification due to errors in quality control in cephalometric radiographs. Standardized lateral cephalographs of a dry skull and a phantom were taken. There were made simulations of technical errors related to kilovoltage, milliampereage, exposition time and position of Al filter, and to horizontal and vertical changes of 3°, 6° and 9° of the phantom in relation to sagital plane and Frankfurt plane, respectively. Twenty-six cephalometric radiographs were selected and 6 examiners (3 orthodontists and 3 radiologists) performed the manual cephalometric analyses of McNamara. ANOVA compared the measurements of 11 variables in the 26 cephalometric analyses. Significant statistically differences were not found among the 6 examiners and among the 11 variables (p > 0.05). Energetic factors had low influence in the quality of the images and on the reproducibility of the cephalometric landmarks. Horizontal variations of head position in relation to sagital plane influenced the quality of cephalometric radiographs. Incorrect cephalometric landmarks compromised the diagnosis, even with experienced examiners. Cephalometry should be complimented by clinical examination, photographs, gnathostatics models and others radiographs to establish diagnosis and treatment.
37

Using Rigid Landmarks to Infer Inter-Temporal Spatial Relations in Spatio-Temporal Reasoning

Bränd, Stefan January 2015 (has links)
Spatio-temporal reasoning is the area of automated reasoning about space and time and is important in the field of robotics. It is desirable for an autonomous robot to have the ability to reason about both time and space. ST0 is a logic that allows for such reasoning by, among other things, defining a formalism used to describe the relationship between spatial regions and a calculus that allows for deducing further information regarding such spatial relations. An extension of ST0 is ST1 that can be used to describe the relationship between spatial entities across time-points (inter-temporal relations) while ST0 is constrained to doing so within a single time-point. This allows for a better ability of expressing how spatial entities change over time. A major obstacle in using ST1 in practise however, is the fact that any observations made regarding spatial relations between regions is constrained to the time-point in which the observation was made, so we are unable to observe inter-temporal relations. Further complicating things is the fact that deducing such inter-temporal relations is not possible without a frame of reference. This thesis examines one method of overcoming these problems by considering the concept of rigid regions which are assumed to always be unchanging and using them as the frame of reference, or as landmarks. The effectiveness of this method is studied by conducting experiments where a comparison is made between various landmark ratios with respect to the total number of regions under consideration. Results show that when a high degree of intra-temporal relations are fully or partially known, increasing the number of landmark regions will reduce the percentage of inter-temporal relations to be completely unknown. Despite this, very few inter-temporal relations can be fully determined even with a high ratio of landmark regions.
38

Nejvyšší soud USA - jeho vznik a prvá klíčová rozhodnutí / The US Supreme Court, its, formation and first key decisions

Červinková, Zuzana January 2015 (has links)
These days, the Supreme Court of the United States represents a very important and irreplaceable role in its home land: protection of constitutionality, explanation of federal laws, as well as appellate court of last resort within the framework of American courts. Today there is no doubt about its jurisdiction, but there were doubts. In the beginning of its existence no one was sure if the Court could overcome the initial obstacles which were in the way. This diploma thesis deals with the initial existence of the Supreme Court of the United States, its role within the framework of the US federal power system, and its progressive integration as equal with the legislative branch and executive power - The United States Congress and the President, respectively. The main objective of this thesis is to introduce the federal judiciary of the United States, show its differences from the continental system, and accentuate the importance of precedents. First, I focus on the history of the United States; colonization by British citizens, the American War for Independence, The Declaration of Independence, and the formation of American statehood in the 1780s, which resulted in the acceptance of one of the longest- lasting written constitutions in the world. After the historical excurse, the thesis focuses on...
39

Architektonická studie cyklistického stadionu /dráhy/ Favorit Brno /na volné ploše v Brně Komárově/. / Architectural study of the cycling stadium / runway / Favorit Brno / on the open space in.

Lukeš, Jaroslav January 2018 (has links)
This diploma thesis looks into the area for sport and recreation in Brno-Komárov. The main part is the project of new arena for track cycling for Favorit Brno. Part of the assignment is also the solution for urban plan and redevelopment of the large area in the south of Brno in city district Brno-Komárov. Urban plan design is framed as conversion of the whole space into sport activities area for broad public. The velodrome itself is based on the idea of a bicycle and its parts as architecturally interesting part of the building, in this case particularly lacing of a wheel. Stadium could become new landmark for its surroundings and draw attention of the general public.
40

Shape Change and Variation in the Cranial Morphology of Wild Canids (Canis lupus, Canis latrans, Canis rufus) Compared to Domestic Dogs (Canis familiaris) Using Geometric Morphometrics

Schmitt, E., Wallace, S. 01 January 2014 (has links)
Wild canid populations exhibit different anatomical morphologies compared to domesticated dogs in North America. This is particularly important concerning archaeological sites, which may contain early domesticated species, for the proper identification of osteological remains. Previous studies have indicated domestic dogs exhibit a shorter rostrum accompanied by a crowded tooth row; however, none describe the overall complexity of these changes. Consequently, using a landmark-based geometric morphometric analysis, cranial morphological characteristics were examined in North American wild canids: the gray wolf (Canis lupus), coyote (Canis latrans), red wolf (Canis rufus), and the domestic dog (Canis familiaris). The shape and size of the cranium in lateral and ventral views were compared between the three wild species to the group of domesticated dogs. Wild canids clustered separately from the domestic group in all statistical analyses. Results indicate an expansion of the orbital region, a compression of the rostrum, and an overall warping in the shape and orientation of the skull. In domestic species, there is also a downward shift in the frontal portion of the skull accompanied by the braincase assuming a more upward position. This technique successfully depicted how slight changes in isolated areas of the cranium can have an impact on the overall shape and morphology of the skull. We presume these changes in cranial anatomy reflect the recent selective pressures domestic dogs have undergone since diverging from their wild ancestors.

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