Дисертації з теми "Laser scanning technique"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-35 дисертацій для дослідження на тему "Laser scanning technique".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Tam, Chung-yan Candy. "Study of rock joint roughness using 3D laser scanning technique." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/b40203487.
Повний текст джерелаTam, Chung-yan Candy, and 譚頌欣. "Study of rock joint roughness using 3D laser scanning technique." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40203487.
Повний текст джерелаYahyavi, Zanjani Matin, Henning Zeidler, André Martin, and Andreas Schubert. "Application of Laser Scanning as a Pre-machining metrology technique in Jet-ECM." Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-227104.
Повний текст джерелаFavey, Etienne. "Investigation and improvement of airborne laser scanning technique for monitoring surface elevation changes of glaciers /." Zürich, 2000. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=14045.
Повний текст джерелаYildiz, Bilge Can. "Imaging Of Metal Surfaces Using Confocal Laser Scanning Microscopy." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613641/index.pdf.
Повний текст джерелаBarnier, Fabien. "Fibre Bragg grating techniques." Thesis, University of Hull, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322570.
Повний текст джерелаLiu, Yan. "Comparison of tactile probe CMM and laser scanning techniques for reverse engineering." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ30955.pdf.
Повний текст джерелаMonte, Jamie Marie, and Jamie Marie Monte. "ROCK MASS CHARACTERIZATION USING LASER SCANNING AND DIGITAL IMAGING DATA COLLECTION TECHNIQUES." Thesis, The University of Arizona, 2004. http://hdl.handle.net/10150/621370.
Повний текст джерелаDoukoglou, Tilemachos D. "Non-parametric system identification techniques for numerical deconvolution of scanning laser microscope images." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61889.
Повний текст джерелаMeadway, Alexander. "Combinations of techniques for the advancement of scanning laser ophthalmology and optical coherence tomography." Thesis, University of Kent, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.653049.
Повний текст джерелаGöbel, Werner. "3D laser-scanning techniques for two-photon calcium imaging of neural network dynamics in vivo /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17655.
Повний текст джерелаDalgleish, Gordon Fraser. "A study of laser-based scanning techniques for defect recognition in sintered cutting tool inserts." Thesis, University of Hull, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389285.
Повний текст джерелаAcharya, Dabit. "COMPARATIVE EXPERIMENTAL STUDIES FOR GLOBAL DAMAGE DETECTION IN PLATES USING THE SCANNING LASER VIBROMETER TECHNIQUES." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1155079600.
Повний текст джерелаTORTAROLO, GIORGIO. "Laser Scanning Microscopy with SPAD Array Detector: Towards a New Class of Fluorescence Microscopy Techniques." Doctoral thesis, Università degli studi di Genova, 2020. http://hdl.handle.net/11567/1000654.
Повний текст джерелаGASPARONI, ANDREA. "Tracking and continuous-tracking scanning laser doppler vibrometer: innovative techniques for the operational characterization of rotating blades." Doctoral thesis, Università Politecnica delle Marche, 2010. http://hdl.handle.net/11566/242169.
Повний текст джерелаPaul, Sanjoy. "CHARGE TRANSPORT IN LIQUID CRYSTALLINE SMECTIC AND DISCOTIC ORGANIC SEMICONDUCTORS: NEW RESULTS AND EXPERIMENTAL METHODOLOGIES." Kent State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=kent1469836810.
Повний текст джерелаLewark, Erick A. "Automated techniques in anthropometry using a three dimensional laser scanner." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176485676.
Повний текст джерелаBenaud, Pia Emma. "Exploring the multiple techniques available for developing an understanding of soil erosion in the UK." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/32939.
Повний текст джерелаFekrmandi, Hadi. "Development of New Structural Health Monitoring Techniques." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/cgi/viewcontent.cgi?article=2923&context=etd.
Повний текст джерелаGraves, Rosemarie Rachel. "Can a hemispherical scanning imaging differential optical absorption spectroscopy technique be used to improve understanding of the emissions, dynamics and chemistry of nitrogen dioxide in the urban boundary layer?" Thesis, University of Leicester, 2014. http://hdl.handle.net/2381/28636.
Повний текст джерелаSUZUKI, SELLY S. "Avaliação histomorfométrica, imunoistoquímica e microtomográfica da ação da terapia laser de baixa potência no processo de reabsorção radicular durante movimentação ortodôntica induzida em ratos." reponame:Repositório Institucional do IPEN, 2016. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26832.
Повний текст джерелаMade available in DSpace on 2016-11-11T17:46:50Z (GMT). No. of bitstreams: 0
A movimentação dentária induzida é um processo biológico complexo mediado por estímulos mecânicos, levando a um subsequente processo de remodelação óssea, podendo haver reabsorção indesejada da raiz dentária provocada pelo excesso de força. Uma vez que a movimentação ortodôntica se baseia em um processo inflamatório localizado, o propósito deste estudo foi avaliar os efeitos do laser de baixa potência no processo de remodelação óssea e reabsorção radicular, buscando correlacionar as mudanças metabólicas observadas a nível celular ocorridas nos dias iniciais da movimentação dentária às alterações teciduais observadas microscopicamente e à arquitetura e morfologia do trabeculado e cortical ósseo. Primeiros molares de sessenta e oito ratos machos Wistar foram submetidos à movimentação induzida, divididos em 3 grupos: controle negativo (nenhuma movimentação), não irradiado (movimentação sem irradiação) e laser (movimentação e irradiação com laser de baixa potência de comprimento de onda de 810 nm, potência de 100 mW, área de 0,02cm2 e energia de 1,5 J/ponto) e eutanasiados nos dias 3, 6, 9, 14 e 21. Mensurações da movimentação dentária e análises histomorfométricas foram realizadas em todos os dias estudados. Análise imunoistoquímica dos marcadores RANKL, OPG e TRAP e avaliações por microscopia eletrônica de varredura (MEV) foram feitas nos dias 3, 6 e 9 e o ensaio Western Blotting para proteínas RANKL e SOFAT e imagens de microtomografia computadorizada (MicroCT) nos dias 14 e 21. Os resultados deste estudo mostraram que a movimentação dentária foi significantemente maior no grupo Laser (aumento em média de 40%) em todos os dias avaliados. O lado de compressão mostrou maior expressão de RANKL e osteoclastos TRAP-positivos nos dias 3, 6 e 9 (p<0,05), promovendo significativa redução na área de osso alveolar presente no lado de compressão nos dias 6, 9 e 14 (p<0,05), e alterações microestruturais, como menor fração de volume ósseo/volume total, menor densidade óssea mineral aos 14 dias. A irradiação com laser também aumentou a expressão de RANKL e a citocina SOFAT no dia 14. No lado de tensão, houve maior expressão de OPG especialmente aos 9 dias (p<0,001) e significativo aumento na área de osso alveolar presente nos dias 14 (p<0,01) e 21 (p<0,05) histomorfometricamente e maior densidade óssea mineral e espessura das trabéculas aos 21 dias (p<0,01). Com relação às áreas de hialinização presentes, os resultados mostraram áreas significantemente reduzidas nos dias 3, 6 e 9 nos grupos irradiados, o que explica o menor número de odontoclastos na superfície radicular nestes dias e a redução significante das áreas de reabsorção radicular observadas nas lâminas histológicas nos dias 9, 14 e 21 e nas imagens de MEV nos dias 3 e 9. Os grupos irradiados também mostraram menor volume das lacunas de reabsorção radicular medidas no MicroCT nos dias 14 e 21, especialmente nos lados de compressão. O estudo concluiu que o laser de baixa potência influenciou a remodelação óssea, aumentou a atividade dos osteoclastos no lado da compressão, e estimulou a formação óssea no de tensão, acelerando significativamente o movimento dentário e potencialmente reduzindo as áreas de necrose no ligamento periodontal e, consequentemente, a reabsorção radicular.
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Huang, Yi-Zhen, and 黃怡蓁. "Rail Wear Inspection by the Laser Scanning Technique." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/r7y6at.
Повний текст джерела國立中央大學
土木工程學系
106
The railway transportation system plays a very important role in the developed countries. In recent years, as increase the speed and frequency of trains, the rail system is damaged more quickly. When the damage of the rail head reaches a degree, the contact area between the head of rail and the train will increase. These results carries the passenger comfort ability, noise problems and even lead to traffic accidents. The railway maintenance group must immediately and accurately measure the rail wearing condition to ensure the safety of the rail system operation. Taiwan inspect the wear damage manually have purchase authorities non-contact inspection vehicles from foreign countries .However, the demand on automatic and fast inspection technique is urgent. This study integrates non-contact laser technology, image processing technology and Matlab programming language to develop a rail wear detection system. The experimental measurement of the rail head profile obtained through the image processing and the reference value of the standard rail section is used to calculate the amount of wearing. Using a hand-held rail abrasion instrument for experimental verification to judge errors, This study sought more efficient detection methods and wanted to develop a fast and accurate track damage detection system to enhance the effectiveness of the maintenance work
Chao, Chun-Wei, and 曹峻瑋. "Application of 3D-Laser Scanning Technique in Tunnel Engineering." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/19596001301890786972.
Повний текст джерела國立臺灣大學
土木工程學研究所
94
Traditional tunnel’s profile monitoring usually costs a lot of manpower, finance and time, and it utilizes only few, selected and fixed observation points in a single tunnel’s profile to get the desired information. In the advancement of optics’ technique and of the performance of computer recently, the development of a new monitoring technique, which is easy to operate, rapid and inexpensive, for tunnel engineering might be helpful for us to equally understand the deformation tendency in a tunnel. From this, derived results can serve as a reference for future repairing of the support system, or the parameters of back analyzing about the development of plastic zone considering long-term and/or regular monitoring works, and for developing a more complete three-dimensional (3-D) information about tunnel’s profile. This study was conducted to develop a new non-contact measurement technique which can be applied to tunnel engineering using a two-dimensional laser image and a program to construct the 3-D information in a certain profile. Different from traditional monitoring, this technique can provide a more complete 3-D profile information by first establishing several points whose 3-D information were already known for calibration. In addition to a small simulative tunnel, a bigger one was constructed in the laboratory to simulate the full-scale tunnel in this study. Based from the results in small tunnel, it was observed that the measurement of deformation behavior from the two successive analyses performed is effective. Also, profiling results from this technique and a total-station-based method were compared and showed that RMSE value can be controlled in about 4 mm in this new technique. Moreover, this research uses image processing to construct a 3-D tunnel’s profile information, thus, the influence are mostly from images. Therefore, improvement in the image processing method is advised to achieve a more precise result.
Chen, Chi-Yuan, and 陳其沅. "Using 3D Laser Scanning Technique in Structure Monitoring and Terrain Modeling." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/92d64z.
Повний текст джерела國防大學理工學院
空間科學碩士班
105
ABSTRACT This research integrates ground LiDAR(Light detection and ranging)- 3D scanning technique and point cloud data, selected Daxi Bridge and nearby valley as test areas, attempt to monitoring the bridge deformation in different times, and producing digital elevation model(DEM). The aims of those studies are summarized as follow: (1) Trying to enhance ground LiDAR technique working and point cloud data processing. (2) Replace the traditional surveying with ground LiDAR technique to implement the feasibility of structural monitoring operations. (3) Compared the DEM made in the same area with ground LiDAR and airborne LiDAR. The results show the accuracy of the point cloud data setting approaches 3 mm. Therefore, the deformation of structures monitoring is over 1 cm, it can be depended on ground LiDAR technique. Besides DEM made, e-GNSS positioning is used to fix control points in this case, and the precision of this system can be reached centimeter level. After fix control points fulfilled, all the point cloud data can be transformed to TWD97 coordinate. Finally, compared with the quality of DEMs made, the benefits of ground LiDAR has that higher resolution and lower costs than those of airborne LiDAR. Keywords: Ground LiDAR, Airborne LiDAR, Point Cloud, DEM, e-GNSS
"Highly Sensitive in-Plane Strain Mapping Using a Laser Scanning Technique." Doctoral diss., 2014. http://hdl.handle.net/2286/R.I.27516.
Повний текст джерелаDissertation/Thesis
Doctoral Dissertation Electrical Engineering 2014
Huang, Nai-Jie, and 黃迺絜. "Analysis of Geological Section for Fault Trenches Using Laser Scanning Technique." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/12578317840577875518.
Повний текст джерела國立臺灣大學
土木工程學研究所
104
Excavating fault trenches is one of main method to study paleoseismology. However, the current approach which costs considerable time and manpower only relies on geologists to recognize the multiple faulting events. Therefore, this study constructs an automatic procedure to map geological sections by using terrestrial LiDAR systems integrated with cameras. The experiment results indicated that the proposed approach can provide high-quality images of fault trenches and amount of image deformation can also be simultaneously evaluated. In the supervised classification procedures, the classification accuracies are also encouraging (overall accuracy 81.18% and kappa 0.7646). Furthermore, by using an existing geological section produced in 2002 with the texture analysis and classification from the image, the major categories can be correctly identified. It gives solid evidence that the terrestrial LiDAR techniques can be efficiently extended to the applications in geological studies.
Chang, Ming-Cheng, and 張明政. "A Study of Using 3D Laser Scanning Technique for Land Parcel Survey-Building Experiment." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/36562905764922151217.
Повний текст джерела國立中興大學
土木工程學系
92
Cadastral maps and cadastral data can provide an very important basis for the land administration management. The accuracy of cadastral maps is closely related to the rights and interests of citizens. Among cadastral surveys, the land parcel survey undoubtedly plays the most important role. Currently, the land parcel survey is only performed to produce 2-D products. In fact, during building state survey, there are lots of spatial information can be obtained. 2-D cadastral data are not sufficient to meet the needs of modern technology for wide uses in the 3-D field. Therefore, it has been forming an inevitable tendency for the adding of cadastral data into diverse precise 3-D spatial information for more widely uses. Nowadays, the technique of long range 3-D laser scanning has become more matured. So, the join of 3-D Laser Scanning in land parcel survey with its high density and precision scanning will make the traditional cadastral maps to produce a 3-D view and meet the requirement for multifunctional uses. Abundant 3-D point cloud is collected after the use of 3-D scanner over the study area where the technology was introduced to perform land parcel survey. Those points were processed and analyzed to establish buildings model. The coordinate systems at scanning stations were then transformed into currently published cadastral coordinate system to make a simulative cadastre. Once the result after comparison and analysis between the simulative one and the original published cadastral map is corresponding to the regulations, a 3-D cadastre joined with stereo building model can hopefully be set up for browse to public. The 3-D model of cadastral information displayed on monitor not only clearly identifies the boundary situation but also the possible disputes between land owners and the cases of land parcel survey would decrease. From this study, it shows: that (1) the largest error was within 4 centimeter for boundary point, which is allowed by to the Regulation for Cadastral Survey. (2) 3-D cadastre can be browsed by the public for the convenience of reading and to build a clear realization over the land in practical situation.
Chen, Li-Sheng, and 陳立笙. "Integration of Digital Photogrammetry and Laser Scanning Technique for Generating High-Quality 3D Point Clouds." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/y88x5u.
Повний текст джерела國立臺灣大學
土木工程學研究所
105
The Light Detection and Ranging (LiDAR) technique is a popular 3D surveying technique nowadays, which is capable of swiftly and precisely acquiring point cloud data with high density, for various engineering monitoring tasks. However, due to the limitation on the mechanism of the used technique, the point cloud data acquired by the LiDAR system frequently reaches unfavorable results, which have the flaws, such as uneven resolution and missing areas. In order to solve this problem, a combined approach for delivering high quality 3D colored point cloud is developed in this study, making the quality improvement of point cloud can be accomplished by integrating accurate geometric data from the LiDAR point cloud with the auxiliary information from images. The proposed approach, firstly determines the camera exterior orientation parameters by applying a semi-automatic process based on image matching technique. Secondly, for improving the geometric integrity of the raw data, the collinearity condition, as well as the geometry information from edge and planar features, will be used for point cloud reconstruction and densification. Finally, the abundant spectral information from multi-view images will be extracted and assigned to the refined point cloud data for generating high-quality result, which can be serve as a reliable and stable data source for further applications. The experiment result indicated that the proposed approach can adequately utilize the information from image data to increase the geometrical detail of the LiDAR point cloud. In conclusion, the quality improvement can be achieved through the use of data from different sources, which can successively reduces the limitation of current 3D surveying techniques, and also provides much more reliable and stable 3D information for applications.
Tseng, Hsing-Yu, and 曾欣郁. "The 3D Laser Scanning Technique for Damage Detection of Mortar Wall-Painting in Traditional Buildings." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/m4ce3j.
Повний текст джерела國立金門大學
土木與工程管理學系碩士班
100
The traditional building walls usually were covered by mortar that become beautifying the space basis. Some paintings of walls are a symbol of cultural heritage and family spirit, at the same time, the wall-painting show increasing living fun and creation, education and art value. For the conservation site, the decorations of historical buildings saved should be regarded as equally important with the building structure. Owing environment factors, the mortar-wall and wall-painting are damaged including humidity variation and water seepage. To the traditional building culture value, the phenomenon is a significant impact. So the investigation and repair for mortar wall-painting is important item for maintenance of historic buildings. The damage detection and investigation of historical buildings is an important reference for restoration and conservation. In recent years, the technology detection system has become the one of essential method in the cultural field. This research is based on the research spirit to use scientific methods to assist professional judgment, trying to capture the space information of point clouds of pre-selected mortar wall-painting using high-precision 3D laser scanning, including 3D coordinates and digital image data. The cases study of the mortar wall-painting is in Tainan area. In the first instance it is using of the handy thermo to obtain the surface temperature of mortar wall-painting for the initial analysis. The result shows that temperature will be lower in the damaged area. Moreover, making 5 types of damage specimen that included powdering, bulging, chapping, flaking and others subsequently obtain the surface data by using 3D laser scanner. Applications on Triangulated irregular networks technology related to the specimen surface changes in the contour maps and detected that the characteristic feature of the different type that coincide the scanning cases. In this study, checking and statistics the success rate of detecting damaged area by infrared temperature sensor and 3D laser scanning technique. Show the reliability of detection technology of this research. So, the research result are joined the existed investigation method and repair damaged mortar wall-painting process to play auxiliary function of science.
詹金萬. "Laser scanning technique for the detection of minority carrier lifetime inhomogeneities and resistivity inhomogeneities in semiconductor." Thesis, 1986. http://ndltd.ncl.edu.tw/handle/91709420570248232417.
Повний текст джерелаDOTTA, GIULIA. "Semi-automatic analysis of landslide spatio-temporal evolution." Doctoral thesis, 2017. http://hdl.handle.net/2158/1076767.
Повний текст джерелаCHU, MEI, and 朱梅. "The Design of Imaging Lens for Coaxial Laser Scanning and Visual Inspection Techniques." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/01156864654364687719.
Повний текст джерела明道大學
光電暨能源工程學系碩士班
98
Owing to the blooming of display industry and the low quality of traditional manufacturing process,the demanding of UV laser manufacture system is increasing. In order to maintain the precision of manufactures, it is necessary to set up the real time monitoring imaging system. The object of this research is to design a coaxial laser scanning and visual inspection imaging lens to monitor the real time image, which is made by the scanning F/ lens for large scale micro lithography. The procedure is to simulate an F/ lens and an imaging lens to meet the initial specification by using Zemax software, and to mock up the image performance with experiment. The initial specification of the coaxial laser scanning and visual inspection imaging lens is listed as follows: ? CCD FOV : 1.6mm * 1.2mm ? CCD Mag : 4X ? Image MTF > =0.3 (@40 lp/mm) (@ 50mm*50mm) The achievements of this research are (1) Design of F-Theta Lens for wavelength 355nm, (2) Design of the coaxial laser scanning and visual inspection imaging lens, (3) Finished the experiment for commercial lens mock-up, and (4) Design of the coaxial laser scanning and visual inspection imaging lens for multi- configuration scanning .
Komba, J. J. (Julius Joseph). "Analytical and laser scanning techniques to determine shape properties of aggregates used in pavements." Diss., 2013. http://hdl.handle.net/2263/32799.
Повний текст джерелаDissertation (MEng)--University of Pretoria, 2013.
gm2013
Civil Engineering
Unrestricted
Baltazar, Luís Filipe Almeida. "Comparing different methods to measure biofilm thickness: the techniques are: optical coherence tomography, confocal laser scanning microscopy and low load compression test." Master's thesis, 2015. http://hdl.handle.net/1822/39586.
Повний текст джерелаBiofilm formation remains a serious concern in industry and in the medical field. They are responsible for huge economical losses in many industrial sectors and for serious infections associated with biomaterial implants and medical devices. These infections are hard to treat because bacteria within the biofilm are more resistant to antibiotics and to the host immune system. Therefore, studying biofilm properties and mechanisms is of utmost relevance to develop efficient approaches to deal with this drawback. Biofilm thickness is an important parameter in biofilm characterization. The main purpose of this thesis was to assess the suitability of Optical Coherence Tomography (OCT) to measure biofilm thickness by comparing the results with the values obtained with the Low Load Compression Test (LLCT) and Confocal Laser Scanning Microscopy (CLSM). OCT is a nondestructive technique, which is increasingly applied on the medical field and allows the acquisition of images in real-time, in situ and with high resolution. Biofilms were grown onto glass slides and the measurements were done in the following order: first OCT, since it is a non-destructive technique, second LLCT and last CLSM. In order to study if slime could influence the measurements, different strains and bacteria exhibiting distinct extracellular polymeric substance (EPS) production capacities were used. Staphylococcus aureus ATCC 12600 is an EPS producer, while Staphylococcus aureus 5298 is not and Streptococcus mutans use extracellular glucans in the presence of sucrose to build its protective matrix, so different treatments with different percentages of sucrose were used in the growth medium during biofilm development. The results obtained proved that OCT is suitable to measure biofilm thicknesses and the presence of slime does not influence the results. In contrast, LLCT measurements showed to be affected by slime and biofilm density. CLSM showed limitations relatively to stain and laser penetration. Additionally, the results obtained emphasize the potential applicability of OCT to investigate the mesoscopic structure of the biofilm.
A formação de biofilmes é um problema sério na industria e na área médica, sendo responsáveis por enormes prejuízos económicos em muitos sectores industriais e por sérias infeções associadas a implantes e dispositivos médicos. Estas infeções são difíceis de tratar, visto que as bactérias quando presentes no biofilme ganham maior resistência a antibióticos e ao sistema imunitário. Por este motivo, estudar as propriedades e mecanismos dos biofilmes é de extrema importância para conseguir desenvolver abordagens eficazes que permitam ultrapassar estes problemas. A espessura dos biofilmes é um parâmetro importante para a sua caracterização. O principal objectivo desta tese foi avaliar a adequação do OCT para medir a espessura dos biofilmes, comparando os resultados com os valores medidos com o LLCT e CLSM. O OCT é uma técnica não destrutiva que tem sido utilizada na área da medicina e permite a aquisição de imagens em tempo real, in-situ e com elevada resolução. Os Biofilmes cresceram em lâminas de vidro e as medições foram feitas na seguinte ordem: primeiro OCT, visto ser uma técnica não destrutiva, seguido do LLCT e por fim o CLSM. Neste trabalho também foi estudado se a presença de EPS pode influenciar as medições em alguma destas técnicas. Para isso foram utilizadas diferentes bactérias e estirpes com capacidades distintas de produção de matrizes extracelulares. A Staphylococcus aureus ATCC 12600 tem capacidade de produzir EPS naturalmente, ao contrário da Staphylococcus aureus 5298. Por outro lado a Streptococcus mutans usa glucanos extracelulares para construir a sua matriz extracelular quando o meio de crescimento possui sacarose. Deste modo foram utilizadas diferentes percentagens deste glícido com o objectivo de obter diferentes tipos de matrizes. Os resultados obtidos provam que o OCT é uma técnica que pode ser usada para medir a espessura de biofilmes. Por outro lado as medições obtidas pelo LLCT são afectadas pela matriz extracelular dos biofilmes e pela sua densidade. O CLSM mostrou limitações relativas a capacidade de penetração do laser e dos corantes. Adicionalmente os resultados obtidos sublinham o potencial do OCT para estudar a estrutura do biofilme ao nível da mesoescala.
Joshi, Abhishek Shriram. "Image Processing and Super Resolution Methods for a Linear 3D Range Image Scanning Device for Forensic Imaging." 2013. http://hdl.handle.net/1805/3414.
Повний текст джерелаIn the last few decades, forensic science has played a significant role in bringing criminals to justice. Shoe and tire track impressions found at the crime scene are important pieces of evidence since the marks and cracks on them can be uniquely tied to a person or vehicle respectively. We have designed a device that can generate a highly accurate 3-Dimensional (3D) map of an impression without disturbing the evidence. The device uses lasers to detect the changes in depth and hence it is crucial to accurately detect the position of the laser. Typically, the forensic applications require very high resolution images in order to be useful in prosecutions of criminals. Limitations of the hardware technology have led to the use of signal and image processing methods to achieve high resolution images. Super Resolution is the process of generating higher resolution images from multiple low resolution images using knowledge about the motion and the properties of the imaging geometry. This thesis presents methods for developing some of the image processing components of the 3D impression scanning device. In particular, the thesis describes the following two components: (i) methods to detect the laser stripes projected onto the impression surface in order to calculate the deformations of the laser stripes due to 3D surface shape being scanned, and (ii) methods to improve the resolution of the digitized color image of the impression by utilizing multiple overlapping low resolution images captured during the scanning process and super resolution techniques.