Magister Chirurgiae Dentium (MChD) / There is no data specific to the Qatari population on the incidence of dental anomalies. The aim of this study was to investigate the incidence of dental anomalies in a Qatari population sample of patients between 6 and 65 years of age and to use the record as a key for human identification in forensic odontology.Records of panoramic radiographs of a Qatari population sample of 457 patients, comprised of (227 females; mean age 16.84 and 230 males; mean age 18.55) were examined to identify all dental anomalies. Dental anomalies were investigated in 4 groups, each group including subdivisions with a total of 15 subdivisions.

The age estimation method as described by Demirjian is the most frequently used tool to estimate the sub-adult dental age in forensic dentistry. This technique has been shown to over or under estimate the chronological age of sub-adults when applied to specific population groups. The aim of this study was to compare a black South African population sample with the original French-Canadian model to determine if Demirjian’s method accurately reflects the true chronological age of this population group. A sample of panoramic radiographs from 279 boys and 325 girls between the ages of 6 and 16 was obtained from the School of Dentistry University of Pretoria, and from orthodontists in private practice in the Pretoria region. The panoramic radiographs were used to score the seven left mandibular teeth. The calculated maturity score was used to determine the Demirjian dental age. All panoramic radiographs were scored by one examiner. A subset of 20 panoramic radiographs was scored by a second examiner and reliability tested using a Wilcoxon Matched Pairs Test. This research showed that black South African children have a more advanced dental age compared to French-Canadian children. Demirjian overestimated the age for boys by 0.8 years and for girls by 0.5 years. The dental age assessment provided by Demirjian is not suitable for black South African children. As a result, new standards of dental age assessment should be established for this population. Copyright / Dissertation (MSc(Odont))--University of Pretoria, 2011. / Oral Pathology and Oral Biology / unrestricted

At a very attractive place of city district Černá pole which is situated close to the city centre. There are old barracks. The aim was to create a new city quarter, from this area with all the facilities ,which are necesaryly. The purpose of my master theses was to create a design of a city hall, which would be situated. The most attractive place, which have interesting and memorable position on the top of the hill. Here is a possibility to create a new centre, of city district which is a very inconsistent today. This place is also well reachable by public transport. The building is created by glass parterre and desk covered by metal mesh. The metal mesh is making a shading as well.

Syfte: Undersöka om skillnad föreligger mellan panorama- och CBCT-röntgen i avseende att bedöma den vertikala höjden av alveolarutskottet vid planering inför implantatbehandling i utvalda regioner. Metod och material: Totalt valdes 68 röntgenbilder, 34 panorama- respektive 34 CBCT-bilder, ut. I samtliga röntgenbilder utfördes mätningar av alveolarutskottets vertikala höjd, vid specifikt utvalda regioner. Observatörerna bestod av fem tandläkarstudenter. Resultat: Både med och utan hänsyn till outliers, visar resultatet en signifikant skillnad mellan de båda röntgenmetoderna. Generellt visas att mätningar i panoramaröntgenbilder återger ett kortare avstånd mellan alveolarutskottets högsta punkt och sinus maxillaris nedre begränsning/foramen mentales övre begränsning jämfört med mätningar i CBCT-röntgenbilderna. Konklusion: Det fanns en signifikant skillnad mellan de båda röntgenmetoderna, denna studie visade att en kortare vertikal benhöjd mättes i panorama- jämfört med i CBCT-röntgenbilder. Resultatet visade att det fanns försumbara interobservatörsskillnader. / Purpose: Investigate whether there is a difference between the panoramic and CBCT X-ray in terms of assessing the vertical height of the alveolar ridge when planning for implant treatment in selected regions. Methodology: A total of 68 X-ray images, 34 panoramic and 34 CBCT images, were selected. In all X-ray images, measurements of the vertical height of the alveolar ridge were performed at specifically selected regions. The observers consisted of five dental students. Results: The result of this study shows a significant difference between the two X-ray methodologies. The measurements made in the panoramic pictures shows a shorter distance between the highest point of the alveolar bone and the lowest point of the maxillary sinus (or the upper limitation of the mental foramen) compared to the same measurements made in the CBCT pictures. Conclusion: There was a significant difference between the two X-ray methods, this study shows that a lower vertical bone height was measured in panoramic compared to CBCT X-rays. The result showed that there were insignificant inter-observer differences.

The master thesis maps the state of the art of visual object tracking in panoramic 360° video. The thesis aims to reveal the main problems related to visual object tracking and moreover focuses on their solution in panoramic videos. In the study of the existing approaches was found that very few solutions of visual object tracking in equirectangular projection of panoramic video have been implemented so far. This thesis therefore presents two improvements of object tracking methods that are based on the adaptation of equirectangular frames. In addition, this thesis brings the manually created dataset of panoramic videos with more than 9900 annotations. Finally the detailed evaluation of 12 well known and state of the art trackers has been performed for this new dataset.

Made available in DSpace on 2015-05-14T12:56:09Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1065398 bytes, checksum: 8472a5b9890ab8a05d3ed62360e845d7 (MD5) Previous issue date: 2010-08-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The frequency of cardiovascular diseases has increased worldwide, and today they are regarded the major cause of mortality and morbidity. Atherosclerosis affects the arteries, with fat deposition in their walls and later calcium salts deposition that may form a calcified atheroma. This study aimed to evaluate the occurrence of calcification in the carotid artery by conventional and digital panoramic radiography in patients aged 40 or older. The study used 728 panoramic radiographs, 600 obtained in direct digital equipment and 128 in film conventional unit. The occurrence of carotid calcification was 7%, and was identified in 51 cases. Patients with calcification in the carotid artery were aged between 43-90 years old, while in women the peak incidence was in the 5th decade of life. In men, the fifth, sixth and eighth decade were the most affected, with no predominance of age. Carotid calcifications were present unilaterally in 30 cases and bilateral in 21 cases. Pearson Chi-square test showed no statistically significant difference in the occurrence of calcification in the carotid artery in male and female, although the percentage was slightly higher among men. Differences in occurrence in conventional and digital panoramic radiographs also showed no statistical difference. The results of this study suggest that panoramic radiography, digital and conventional can be used as an auxiliary method in the identification of carotid calcification. / A frequência de doenças cardiovasculares aumentou mundialmente, sendo consideradas na atualidade como uma das principais causas de mortalidade e morbidade. A aterosclerose acomete as artérias, caracterizando-se pelo acúmulo de gordura na parede das mesmas, a qual sofre a deposição subsequente de sais de cálcio, formando o ateroma calcificado. O presente trabalho teve como objetivo identificar a presença de calcificação na artéria carótida através da radiografia panorâmica digital e convencional de pacientes com 40 anos ou mais de idade. A amostra foi constituída de 728 radiografias panorâmicas, sendo 600 delas obtidas em equipamento digital e 128 em aparelho convencional. A ocorrência de calcificação carotídea foi de 7%, sendo identificada em 51 casos. Os pacientes com calcificação na artéria carótida pertenciam à faixa etária de 43 a 90 anos de idade, sendo que nas mulheres o pico de ocorrência foi na 5ª década de vida. Nos homens, a quinta, a sexta e a oitava década foram as mais acometidas, sem predomínio de faixa etária. As calcificações carotídeas estavam presentes unilateralmente em 30 casos e bilateralmente em 21 casos. Ao aplicar o teste Qui-quadrado de Pearson, não se observou diferença estatisticamente significante na ocorrência de calcificação na artéria carótida quando se considerou o gênero masculino e feminino, apesar do valor percentual ter sido discretamente maior nos homens. O mesmo foi evidenciado quando se avaliou a diferença da ocorrência da calcificação carotídea na radiografia panorâmica digital e na convencional. Os resultados deste estudo sugerem que a radiografia panorâmica obtida tanto pelo método digital quanto pelo convencional pode contribuir na identificação de calcificação carotídea.

Virtual camera realisation and the proposition of trapezoidal camera architecture are the two broad contributions of this thesis. Firstly, multiple camera and their arrangement constitute a critical component which affect the integrity of visual content acquisition for multi-view video. Currently, linear, convergence, and divergence arrays are the prominent camera topologies adopted. However, the large number of cameras required and their synchronisation are two of prominent challenges usually encountered. The use of virtual cameras can significantly reduce the number of physical cameras used with respect to any of the known camera structures, hence adequately reducing some of the other implementation issues. This thesis explores to use image-based rendering with and without geometry in the implementations leading to the realisation of virtual cameras. The virtual camera implementation was carried out from the perspective of depth map (geometry) and use of multiple image samples (no geometry). Prior to the virtual camera realisation, the generation of depth map was investigated using region match measures widely known for solving image point correspondence problem. The constructed depth maps have been compare with the ones generated using the dynamic programming approach. In both the geometry and no geometry approaches, the virtual cameras lead to the rendering of views from a textured depth map, construction of 3D panoramic image of a scene by stitching multiple image samples and performing superposition on them, and computation of virtual scene from a stereo pair of panoramic images. The quality of these rendered images were assessed through the use of either objective or subjective analysis in Imatest software. Further more, metric reconstruction of a scene was performed by re-projection of the pixel points from multiple image samples with a single centre of projection. This was done using sparse bundle adjustment algorithm. The statistical summary obtained after the application of this algorithm provides a gauge for the efficiency of the optimisation step. The optimised data was then visualised in Meshlab software environment, hence providing the reconstructed scene. Secondly, with any of the well-established camera arrangements, all cameras are usually constrained to the same horizontal plane. Therefore, occlusion becomes an extremely challenging problem, and a robust camera set-up is required in order to resolve strongly the hidden part of any scene objects. To adequately meet the visibility condition for scene objects and given that occlusion of the same scene objects can occur, a multi-plane camera structure is highly desirable. Therefore, this thesis also explore trapezoidal camera structure for image acquisition. The approach here is to assess the feasibility and potential of several physical cameras of the same model being sparsely arranged on the edge of an efficient trapezoid graph. This is implemented both Matlab and Maya. The quality of the depth maps rendered in Matlab are better in Quality.

The thesis explores how painting is affected by its sonic environment. The research stems from an artistic response to noise in the environment and how this can be explored through artistic practice. The boundaries of art have and continue to be challenged as visual art has embraced an increasing range of approaches. This research explores the visual experience of viewing a painting alongside the all-encompassing time based nature of a sonic experience and readdresses the way painting operates within its own sound environment. It asks how these different elements can affect the reading of one another and in particular focuses on installations in extreme acoustic spaces, such as anechoic and reverberation chambers. It investigates how introducing sound to the painting arena can affect the reading and also transform the parameters of the painting. The research is practice-based and takes the form of a series of exhibitions, latterly in the form of site-specific installations, which have been evaluated, interpreted and responded to. This has led to a fundamental investigation, both practical and theoretical, into the way that sound and vision work together and how they relate within the context of art. Through the research the format of the painting developed in tandem with the temporal and audio considerations, resulting in all-encompassing installations bringing together panoramic paintings and 3D soundscapes.

Šiame darbe pateikiamas apibendrintas automatinio vaizdų jungimo į panoramas algoritmas, detaliai aptariami algoritmo žingsniai ir galimas našumo didinimas lygiagretaus programavimo priemonėmis. Tyrime aprašyti vaizdų jungimo bandymai panaudojant kelias populiarų vaizdų bruožų alternatyvas. Taip pat pristatoma praktinė vaizdų jungimą panaudojanti aplikacija. / This study presents a generalization of an automated image stitching algorithm, describes it's steps in great detail and discusses possible performance improvements by use of parallel execution. Results of stitching experiments using a couple of modern and popular image feature alternatives are shown. A practical application using an implementation of automated image stitching is presented.

Abstract Medical x-ray imaging is used to visualise patients’ anatomical structures and in some cases their physiology. X-rays are ionizing radiation, thus their use needs to be optimised, as stochastic effects are assumed to increase linearly with the exposure dose. Imaging protocols need to be optimised to a radiation dose level that follows the as low as reasonably achievable principle without compromising the diagnostic value of the image. Different methods can be used to help in the optimisation process, such as simulations, radiation dose and image quality assessments with dosimeters and phantoms and utilising the latest technology in the most efficient way. The purpose of this doctoral thesis was to investigate the applicability of metal-oxide-semiconductor-field-effect-transistor (MOSFET) dosimeters for dose determinations in conventional x-ray and computed tomography (CT) examinations. Additionally, dose optimising methods were investigated in dental panoramic imaging using radiophotoluminescence (RPL) dosimeters. Anthropomorphic phantoms were used in every study to simulate patients, as their structures enable dosimeters to be positioned at locations that correspond to different organs. The MOSFET’s properties for dose determinations were evaluated against the reference dosimeter in a conventional x-ray set-up. Comparisons of absorbed and effective doses in thorax x-ray imaging were made between RPLs, MOSEFTs and Monte Carlo simulations. The effect of the organ-based tube current modulation and bismuth shields were compared against the reference imaging method in a chest CT with one scanner model. Absorbed doses and quantitative image quality were evaluated using each method. Possible dose reduction from segmented dental panoramic tomography (sDPT) imaging was compared against full DPT. Dose measurements were done using RPL dosimeters in pediatric and adult set-up using phantoms. MOSFETs are accurate enough to be used in conventional x-ray and CT, but they require a careful calibration before use as their reproducibility is limited with low doses. Bismuth shields provided the best dose reduction, but with a negative impact on quantitative image quality, especially when metal artefact removal software was used. The final study showed that the use of sDPT programmes and pediatric protocols enable a notably dose reduction compared to the full DPT adult protocol. / Tiivistelmä Lääketieteellisessä kuvantamisessa käytetään röntgensäteilyä potilaan anatomian ja joissain tapauksissa fysiologian visualisointiin. Röntgensäteily on ionisoivaa ja stokastisten vaikutusten kasvaessa oletettavasti lineaarisesti säteilyn funktiona, tulee säteilyn olla kokonaisvaltaisesti optimoitua. Kuvauksissa käytetyn röntgensäteilyn käytön tulee noudattaa ALARA-periaatetta, minkä vuoksi kuvauksessa tulee käyttää niin vähän säteilyä kuin vain mahdollista, diagnostiikan vaarantumatta. Optimoinnin apuna voidaan käyttää esim. simulointeja, annos- ja kuvanlaatumäärityksiä dosimetreilla ja fantomeilla, tai laitevalmistajien tuomia uusia teknologioita. Tämän väitöskirjan tarkoituksena oli tutkia metallioksidi-puolijohdekanavatransistorien (MOSFET) soveltuvuutta natiiviröntgentutkimuksissa ja tietokonetomografiassa (TT). Lisäksi työssä tutkittiin hammaskuvauksissa käytettyjä annossäästömenetelmiä radiofotoluminesenssidosimetreilla (RPL). Potilasvasteena työssä käytettiin antropomorfisia fantomeita, minkä ansiosta säteilyannoksia voidaan mitata eri elimiä vastaavilta kohdilta. MOSFET annosmittarin ominaisuuksia arvioitiin natiiviröntgenasetelmassa referenssimittariin nähden. Absorboituneiden ja efektiivisten annosten eroa MOSFET:tien, RPL:ien ja simulointien kesken tutkittiin keuhkoröntgentutkimuksessa. Pintakudoksia säästävän putkivirranmodulointimenetelmän ja vismuttisuojien vaikuttavuutta verrattiin TT:ssä referenssimetelmää vasten. Vaikuttavuutta arvioitiin absorboituneiden annosten ja kvantitatiivisen kuvanlaadun avulla. Segmentoidun hammaspanoraamakuvauksen (sDPT) annossäästömahdollisuuksia verrattiin tavalliseen panoraamakuvaukseen. Annosmääritykset tehtiin käyttäen RPL dosimetreja lapsi- ja aikuisfantomeissa. MOSFET dosimetreja voidaan käyttää annosmäärityksiin natiiviröntgenkuvauksissa ja TT:ssä, mutta niiden kalibrointi ja toistettavuus matalilla annoksilla aiheuttaa kuitenkin rajoituksia niiden käytölle. Vismuttisuojat tuottivat parhaan annossäästön, huonontaen kuitenkin kuvanlaatua. Kuvanlaadun huonontuminen oli erityisen huomattavaa, kun metallista aiheutuvien kuvavirheiden poistamiseen suunniteltua ohjelmaa käytettiin. Viimeinen tutkimus osoitti, että sDPT ohjelmat ja lapsille suunnatut protokollat mahdollistavat huomattavan annossäästön verrattuna aikuisten kokopanoraamaan.