Relevant bibliographies by topics / Three-dimensional scanner

Academic literature on the topic 'Three-dimensional scanner'

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Published: 14 March 2023

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Journal articles on the topic "Three-dimensional scanner"

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Carvalho, William S., Viviane de S. M. Almeida, Leonardo Provedel, Anderson da S. Maciel, and Viviane A. Sarmento. "Volumetric Evaluation of 3D Models Generated by Different Surface Treatment Protocols." European Journal of Dental and Oral Health 3, no. 5 (December 23, 2022): 5–8. http://dx.doi.org/10.24018/ejdent.2022.3.5.229.

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The objective of this study was to compare the volume of three-dimensional (3D) models generated by different scanners and computational modeling protocols. Eight dry mandibles were scanned by five different computed tomography (CT) scanners and by a 3D-scanner. Three-dimensional models were generated, received different surface treatment processes, and the final volume of the 3D models was compared. The results show that there was no significant difference among the volume of the 3D models generated by the different CT scanners and surface treatment techniques, however, the model volume generated by the 3D-scanner show the highest volume. It can be concluded that the different combinations of surface treatment protocols did not determine differences in the model volume generated by different CT and CBCT scanners and that the 3D-scanner determined the highest volume models.
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Ahdi Rezaeieh, Sasan, Ali Zamani, Konstanty Bialkowski, Graeme Macdonald, and Amin Abbosh. "Three-Dimensional Electromagnetic Torso Scanner." Sensors 19, no. 5 (February 27, 2019): 1015. http://dx.doi.org/10.3390/s19051015.

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A three-dimensional (3D) electromagnetic torso scanner system is presented. This system aims at providing a complimentary/auxiliary imaging modality to supplement conventional imaging devices, e.g., ultrasound, computerized tomography (CT) and magnetic resonance imaging (MRI), for pathologies in the chest and upper abdomen such as pulmonary abscess, fatty liver disease and renal cancer. The system is comprised of an array of 14 resonance-based reflector (RBR) antennas that operate from 0.83 to 1.9 GHz and are located on a movable flange. The system is able to scan different regions of the chest and upper abdomen by mechanically moving the antenna array to different positions along the long axis of the thorax with an accuracy of about 1 mm at each step. To verify the capability of the system, a three-dimensional imaging algorithm is proposed. This algorithm utilizes a fast frequency-based microwave imaging method in conjunction with a slice interpolation technique to generate three-dimensional images. To validate the system, pulmonary abscess was simulated within an artificial torso phantom. This was achieved by injecting an arbitrary amount of fluid (e.g., 30 mL of water), into the lungs regions of the torso phantom. The system could reliably and reproducibly determine the location and volume of the embedded target.
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Borodina, Irina D., Leon S. Grigoryants, Magammed A. Gadzhiev, Svetlana S. Apresyan, Roman V. Batov, Alexander G. Stepanov, and Samvel V. Apresyan. "Comparative evaluation of the accuracy of the dental arch display using modern intraoral three-dimensional scanners." Russian Journal of Dentistry 26, no. 4 (September 29, 2022): 287–97. http://dx.doi.org/10.17816/1728-2802-2022-26-4-287-297.

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BACKGROUND: At present, modern dentists used dental intraoral three-dimensional (3D) scanners routinely in their daily work. Obtaining an optical 3D image of the teeth and dentition helps avoid errors at the stage of obtaining traditional silicone impressions and significantly reduces the level of discomfort during dental procedures. Intraoral scanner systems are commercially available today. Despite their advantages over traditional silicone impressions, the accuracy of the optical impressions obtained during total and subtotal prosthetics on the upper and lower jaw are still questionable. AIM: This study aimed to evaluate the accuracy of scanning models of the patients dentition obtained using intraoral scanners and to determine the currently available models of digital devices that are optimal in terms of price and quality. MATERIAL AND METHODS: The reference scan (master model) was an optical image of the reference model of the upper jaw of a patient with a full dentition made by additive 3D-printing technology obtained using a laboratory scanner. To level out the shrinkage errors of photopolymerization materials, the resulting model was scanned on the same day using intraoral scanners selected for the study. The obtained scan results were compared with the reference scan of the control group. Based on the measurements made at reference points, the average error value relative to the master model and its precision were calculated for each scanner. In addition to the average values, the error parameters of the scanners in the frontal and chewing sections were calculated, as well as the arc error, which was equal to the difference in the values of the discrepancy at the reference points at which the maximum and minimum values were obtained. The cost and availability of scanners on the domestic market, under the sanctions policy of foreign countries, were also considered. RESULTS: The CEREC Primescan AC scanner showed the best accuracy according to the results of model discrepancies. It has an average error of 13.727.34. The arc error was 18.8 microns, and the discrepancies in the frontal area and chewing area were 18 and 6.8 microns, respectively. 3Shape Trios 3 scanner has the closest accuracy, with an average error of 16.285.94 microns. The error value of Aoralscan 3 was 42.0818.34 microns, its arc accuracy was 65 microns, and the discrepancies in the frontal and chewing areas were 33 and 55.1 microns, respectively. Emerald S Mode C had an average error of 35.8422.29 microns, which was higher than that of Medit i500 and Aoralscan 3; however, Aoralscan 3 showed better precision (18.34 microns versus 22.29 microns). According to the comparison results of the models in the MeshLab program, CEREC Primescan AC showed the smallest median of distances (18 microns). The TRIOS 3 and Emerald S Mode C differed from the standard by an average of 29 microns, and Aoralscan 3 scanners had of 33 microns and Medit i500 had 41 microns. CONCLUSION: The precision of Aoralscan 3 scanner, which is the best among its analogs in the price category, makes it the most affordable scanner for dental surgical, orthodontic, and orthopedic fields. CEREC Primescan AC is the leader of the premium scanners involved in the study and available in the dental market.
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Mutwalli, Hussam, Michael Braian, Deyar Mahmood, and Christel Larsson. "Trueness and Precision of Three-Dimensional Digitizing Intraoral Devices." International Journal of Dentistry 2018 (November 26, 2018): 1–10. http://dx.doi.org/10.1155/2018/5189761.

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Aim. To measure the trueness and precision under repeatable conditions for different intraoral scanners (IOSs) when scanning fully edentulous arch with multiple implants. Materials and Methods. Three IOSs and one industrial scanner were used to scan one edentulous master cast containing five implant scan bodies and three spheres. The cast was scanned thirty times with each scanner device. All scans were analyzed in the inspect software, and three-dimensional locations of the implants and the interarch distance between the spheres were measured. The values were compared to measurements made with one coordinate measuring machine (true value). One-way ANOVA was used to calculate the differences between IOSs and in comparison with the true value. Results. Significant differences were found between all IOSs. For the implant measurements, Trios 3 had the lowest trueness (≤114 μm), followed by Trios 3 mono (≤63 μm) and Itero element (≤−41 μm). Trios had the lowest precision (≤135 μm), followed by Itero element (≤101 μm) and Trios 3 mono (≤100 μm). With regard to the interarch distance measurements, Trios 3 had the lowest trueness (≤68 μm), followed by Trios 3 mono (≤45 μm) and Itero element (≤40 μm). Trios 3 had the lowest precision (≤206 μm), followed by Itero element (≤124 μm) and Trios 3 mono (≤111 μm). Conclusion. The results from this in vitro study suggest that precision is low for the tested IOS devices when scanning fully edentulous arches with multiple implants.
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Huang, Yunbao, and Xiaoping Qian. "A Dynamic Sensing-and-Modeling Approach to Three-Dimensional Point- and Area-Sensor Integration." Journal of Manufacturing Science and Engineering 129, no. 3 (November 3, 2006): 623–35. http://dx.doi.org/10.1115/1.2714585.

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The recent advancement of 3D non-contact laser scanners enables fast measurement of parts by generating a huge amount of coordinate data for a large surface area in a short time. In contrast, traditional tactile probes in the coordinate measurement machines can generate more accurate coordinate data points at a much slower pace. Therefore, the combination of laser scanners and touch probes can potentially lead to more accurate, faster, and denser measurements. In this paper, we develop a dynamic sensing-and-modeling approach for integrating a tactile point sensor and an area laser scanner to improve the measurement speed and quality. A part is first laser scanned to capture its overall shape. It is then probed via a tactile sensor where the probing positions are dynamically determined to reduce the measurement uncertainty based on a novel next-best-point formulation. Technically, we use the Kalman filter to fuse laser-scanned point cloud and tactile points and to incrementally update the surface model based on the dynamically probed points. We solve the next-best-point problem by transforming the B-spline surface’s uncertainty distribution into a higher dimensional uncertainty surface so that the convex hull property of the B-spline surface can be utilized to dramatically reduce the search speed and to guarantee the optimality of the resulting point. Three examples in this paper demonstrate that the dynamic sensing-and-modeling effectively integrates the area laser scanner and the point touch probe and leads to a significant amount of measurement time saving (at least several times faster in all three cases). This dynamic approach’s further benefits include reducing surface uncertainty due to the maximum uncertainty control through the next-best-point sensing and improving surface accuracy in surface reconstruction through the use of Kalman filter to account various sensor noise.
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Lee, Keun Ho, Sung Jae Kim, Yong Ho Cha, Jae Lim Kim, Dong Kyu Kim, and Sang Jun Kim. "Three-dimensional printed prosthesis demonstrates functional improvement in a patient with an amputated thumb: A technical note." Prosthetics and Orthotics International 42, no. 1 (December 20, 2016): 107–11. http://dx.doi.org/10.1177/0309364616679315.

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Background and Aim: Three-dimensional printer is widely used in industry, biology, and medical fields. We report a finger prosthesis produced by a three-dimensional scanner and printer for a 67-year-old man with a right thumb amputation above the metacarpophalangeal joint. Technique: His right amputated and left intact hands were scanned with a three-dimensional scanner, and the left-hand image was rotated to the right side to design the right thumb prosthesis. The designed prosthesis was printed with a three-dimensional printer using the fused filament fabrication output system. Discussion: The Jebsen–Taylor hand function test and Box and Block Test scores improved after application of the prosthesis. Most Quebec User Evaluation of Satisfaction with Assistive Technology results were “very satisfied,” and most Orthotics and Prosthetics Users’ Survey results were “very easy.” Preparing the prosthesis made by three-dimensional scanner and three-dimensional printer was faster and cheaper than preparing a conventional prosthesis. Clinical relevance Using three-dimensional scanning and printing technique, we can easily produce specifically shaped finger prostheses for specific movements in amputated patients with low cost.
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Mezei, Adrián, and Tibor Kovács. "Curvature Adaptive 3D Scanning Transformation Calculation." Periodica Polytechnica Electrical Engineering and Computer Science 62, no. 4 (June 13, 2018): 107–16. http://dx.doi.org/10.3311/ppee.11540.

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Three-dimensional objects can be scanned by 3D laser scanners that use active triangulation. These scanners create three-dimensional point clouds from the scanned objects. The laser line is identified in the images, which are captured at given transformations by the camera, and the point cloud can be calculated from these. The hardest challenge is to construct these transformations so that most of the surface can be captured. The result of a scanning may have missing parts because either not the best transformations were used or because some parts of the object cannot be scanned. Based on the results of the previous scans, a better transformation plan can be created, with which the next scan can be performed. In this paper, a method is proposed for transforming a special 3D scanner into a position from where the scanned point can be seen from an ideal angle. A method is described for estimating this transformation in real-time, so these can be calculated for every point of a previous scan to set up a next improved scan.
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Nouri, Taoufik. "Three-dimensional scanner based on fringe projection." Optical Engineering 34, no. 7 (July 1, 1995): 1961. http://dx.doi.org/10.1117/12.200616.

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Lee, Changyeop, Wonseok Choi, Jeesu Kim, and Chulhong Kim. "Three-dimensional clinical handheld photoacoustic/ultrasound scanner." Photoacoustics 18 (June 2020): 100173. http://dx.doi.org/10.1016/j.pacs.2020.100173.

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Park, Jae Won, Se An Oh, Ji Woon Yea, and Min Kyu Kang. "Fabrication of malleable three-dimensional-printed customized bolus using three-dimensional scanner." PLOS ONE 12, no. 5 (May 11, 2017): e0177562. http://dx.doi.org/10.1371/journal.pone.0177562.

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Dissertations / Theses on the topic "Three-dimensional scanner"

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Lewark, Erick A. "Automated techniques in anthropometry using a three dimensional laser scanner." Ohio : Ohio University, 1998. http://www.ohiolink.edu/etd/view.cgi?ohiou1176485676.

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Moreira, Sandro Silva [UNESP]. "Projeto e construção de um scanner tridimensional baseado no método de triangulação a laser utilizando softwares livres." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/148571.

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A modelagem tridimensional muito já contribuiu com a indústria do entretenimento e agora tem sido amplamente utilizada na manufatura e criação de novos produtos. A possibilidade de se ter um modelo de um produto a um preço menor e com uma maior rapidez tem feito essa técnica ser cada vez mais aceita em todas as áreas da engenharia. Quando já se tem um modelo real e deseja-se realizar alguma modificação, simulação ou mesmo replicar o produto, a engenharia reversa muito pode contribuir, pois permite a obtenção do modelo tridimensional a partir do objeto real. Os equipamentos de digitalização tridimensional têm um alto custo de investimento, mesmo os de baixa precisão. A comunidade de entusiastas de software e hardware livre busca também distribuir e popularizar o conhecimento compartilhando suas descobertas e contribuindo abertamente com outras iniciativas. Buscamos nesse projeto construir um scanner 3D utilizando software e hardware livre utilizando componentes de baixo custo e fácil aquisição, estabelecendo seus limites técnicos, estimulando assim a adoção de técnicas de engenharia reversa. O processo de calibragem, captura e pós tratamento da nuvem de pontos obtidas foi detalhado na construção de modelos para comparação de dimensões e levantamento de características da superfície do material.
The three-dimensional modeling has contributed much to the entertainment industry and has now been widely used in manufacturing and creating new products. The possibility of having a model of a product at a lower price and a higher speed have made this technique is increasingly accepted in all fields of engineering. When there is already a real model and you want to make any changes, simulation or even replicate the product, reverse engineering can greatly contribute, as it allows to obtain three-dimensional model from the real object. The three-dimensional scanning equipment have a high investment cost, even low accuracy. The community of enthusiasts of open source and open hardware also distribute and popularize knowledge sharing his findings and openly contribute to other initiatives. We seek in this study, build a scanner 3D using free software and hardware components using low-cost and easy acquisition, establishing its technical limits, stimulating the adoption of reverse engineering techniques. The calibration, capture and post-treatment process of the cloud of points obtained was detailed in the construction of models for comparison of dimensions and survey of surface characteristics of the material.
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Moreira, Sandro Silva. "Projeto e construção de um scanner tridimensional baseado no método de triangulação a laser utilizando softwares livres /." Ilha Solteira, 2016. http://hdl.handle.net/11449/148571.

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Orientador: Ruis Camargo Tokimatsu
Resumo: A modelagem tridimensional muito já contribuiu com a indústria do entretenimento e agora tem sido amplamente utilizada na manufatura e criação de novos produtos. A possibilidade de se ter um modelo de um produto a um preço menor e com uma maior rapidez tem feito essa técnica ser cada vez mais aceita em todas as áreas da engenharia. Quando já se tem um modelo real e deseja-se realizar alguma modificação, simulação ou mesmo replicar o produto, a engenharia reversa muito pode contribuir, pois permite a obtenção do modelo tridimensional a partir do objeto real. Os equipamentos de digitalização tridimensional têm um alto custo de investimento, mesmo os de baixa precisão. A comunidade de entusiastas de software e hardware livre busca também distribuir e popularizar o conhecimento compartilhando suas descobertas e contribuindo abertamente com outras iniciativas. Buscamos nesse projeto construir um scanner 3D utilizando software e hardware livre utilizando componentes de baixo custo e fácil aquisição, estabelecendo seus limites técnicos, estimulando assim a adoção de técnicas de engenharia reversa. O processo de calibragem, captura e pós tratamento da nuvem de pontos obtidas foi detalhado na construção de modelos para comparação de dimensões e levantamento de características da superfície do material.
Mestre
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Fracarolli, Juliana Aparecida 1984. "Levantamento das coordenadas espaciais de corpos vegetais associado ao mapeamento de bioatividade e cor." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257126.

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Orientadores: Inacio Maria Dal Fabbro, Adilson Machado Enes
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola
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Resumo: Técnicas ópticas vêm sendo utilizadas para diversas finalidades técnicas e científicas. Algumas técnicas ópticas se caracterizam como métodos robustos, de baixo custo, não invasivos e não destrutivos para avaliação de materiais diversos, como produtos agrícolas, havendo aplicações desde a engenharia até a área da saúde humana e animal. Neste trabalho propõem-se a avaliação de frutos através da combinação de duas técnicas ópticas cujos estudos vêm comprovando suas aplicabilidades como métodos alternativos e inovadores, os quais empregam equipamentos de baixo custo na aquisição dos dados, permitindo automação de processos de seleção e classificação de produtos. Uma dessas técnicas é conhecida como Biospeckle, a qual fornece informações referentes à qualidade do material biológico em nível de estruturas celulares e a outra é o escaneamento com linha laser, que permite a obtenção de geometria do objeto nos eixos Xi (i = 1,2,3). O objetivo é proceder a um levantamento topográfico digital de materiais biológicos combinando o posicionamento geométrico dos pontos da imagem com informações referentes à atividade biológica. Foi realizada ainda a diferenciação entre frutos de formato variado, a classificação de frutos por formato, classe, coloração e defeitos por meio de processamento de imagens. Dessa forma é possível observar frutos com irregularidades superficiais, maturidade, danos mecânicos e latentes, entre outros. Esta pode se tornar a base para a seleção automática de produtos agrícolas. Foram utilizados um emissor de linha laser de diodo com 632 nm de comprimento de onda, luz branca difusa, câmera CCD, computador, mesa óptica, mamões, peras, tomates e esferas de isopor, bem como softwares ImageJ, Octave, Matlab. Foram desenvolvidos cinco programas computacionais para processamento das imagens. Foram realizados cinco experimentos, a saber: (1) Avaliação da Maturidade de Frutos; (2) Reconstrução Tridimensional e Mapeamento da Bioatividade; (3) Detecção de Formato Variado; (4) Mapeamento por Formato, Classe e Coloração; (5) Detecção de Defeitos. Na Avaliação da Maturidade foram correlacionados índices de maturidade tradicionais (parâmetros de Hunter L a b, pH, Sólidos Solúveis Totais (SST), a relação Sólidos Solúveis Totais e Acidez Total Titulável (SST/ATT), Módulo de Elasticidade, massa e diâmetro) e a técnica óptica Biospeckle, pelo cálculo do Momento de Inércia (MI). Para a Reconstrução Tridimensional os frutos foram rotacionados através de um motor de passo. A cada passo do motor, o fruto foi iluminado pela linha laser projetada e fotografado para obtenção dos dados de geometria e Biospeckle pelo método LASCA (Laser Speckle Contrast Analysis). Foi analisada a correlação entre os índices de maturidade tradicionais e os valores de MI na avaliação da maturidade. Esta tese mostra que é possível avaliar a maturidade dos frutos através do Biospeckle. Obteve-se um mapa tridimensional que integra as informações de topografia e bioatividade do fruto. Obteve-se, ainda, a detecção de formato variado, a classificação de frutos por mapeamento por formato, classe e coloração e detecção de defeitos através de software
Abstract: Optical techniques have been used for both technical and scientific purposes. Optical techniques are usually characterized as being robust, inexpensive, non-invasive and non-destructive methods in to evaluate a diversity of materials which include agricultural derived products. It also shows applications ranging from engineering to human and animal health. In this doctoral dissertation, a new technique to evaluate some fruit properties is proposed. It combines two optical techniques (i.e. Biospeckle and Scan-line laser) whose applicability has been demonstrated as being alternative and innovative. The new proposed technique allows low-cost data acquisition, automation of the entire process, and a proper selection and classification method of vegetable bodies (e.g. fruits). Biospeckle allows obtaining information regarding the quality level of biological material into cellular structures. Scan-line laser enables the attainment of the object geometry on the axes Xi (i=1,2,3). The main purpose of this doctoral dissertation is to obtain a digital survey of biological materials (i.e. papaya, pear and tomato) integrating both geometric positioning and information concerning to its biological activity. The differentiation between different fruit shapes, fruit sorting by size, class, color and defects through image processing was also carried out. Thus it was also possible to observe fruits with surface irregularities, maturity, and mechanical damage, among others. This is the basis proposed for the automatic selection of agricultural products. The following materials were employed in the tests: a line-emitting diode laser with a wavelength of 632 nm, diffuse white light, CCD camera, computer, optical table, papaya, pear and tomato fruits and polystyrene spheres. The softwares utilized were: ImageJ, Octave, Matlab. A total of five computer programs were developed for the image processing procedures. Five experiments were performed: (1) Maturity Assessment of Fruits; (2) Three Dimensional Reconstruction and Mapping of Bioactivity; (3) Miscellaneous Format Detection; (4) Mapping Format, Class and Coloration; (5) Defect Detection. In Maturity Assessment there were correlated traditional methods to verify the maturity (the Hunter parameters L a b, pH, Total Soluble Solids (TSS), the relationship between Total Soluble Solids and Titratable Acidity (TSS/TA), Modulus of Elasticity, weight and diameter) and the optical technique Biospeckle by calculating the Moment of Inertia (MI). For the Three Dimensional Reconstruction the fruits were rotated by a stepper motor. At every step of the motor, the fruit was illuminated by the projected laser line and photographed in order to obtain both geometric and biospeckle data by the LASCA (Laser Speckle Contrast Analysis) method. The correlation between traditional methods for the maturity assessment and values of MI was analyzed. This doctoral dissertation shows that it is possible to evaluate the maturity of fruits through Biospeckle. A three-dimensional map that includes topographical information and bioactivity of the fruit was generated. Also a software can now detect variations in size, classify fruit shapes, color and class as well as defect detection efficiently.
Doutorado
Maquinas Agricolas
Doutora em Engenharia Agrícola
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OBRADOVIC, Marija. "Interdisciplinary three-dimensional investigation of the Early Prehistoric deposits of Fumane Cave (Verona, Italy)." Doctoral thesis, Università degli studi di Ferrara, 2016. http://hdl.handle.net/11392/2496455.

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La tesi è focalizzata sulla realizzazione delle indagini geofisiche e topografiche tridimensionali, applicabile sui siti preistorici e basate sull’esempio della Grotta di Fumane (Verona, Italia). I metodi applicati includono la tomografia di resistività elettrica (ERT), le onde sismiche di superficie (HVSR), laser scanner e fotogrammetria. Lo studio ha coinvolto l'uso delle due configurazioni elettrodiche, Wenner-Schlumberger (WSC) e PolePole (PP), sia per avere maggiore risoluzione nei primi 2-3 metri del deposito, sia per ottenere informazioni sulla profondità totale del deposito e la posizione del sostrato roccioso. Le onde sismiche superficiali possono mostrare il rapporto di ampiezza fra gli elementi orizzontali e verticali del moto secondo lo spessore e parametri elastici di strati in prossimità della superficie, variazioni di velocità e fornire informazioni sulla geometria della roccia. Modelli d’inversione 2D e 3D hanno prodotto le immagini suggestive di resistività, che hanno fornito informazioni sul sottosuolo, indicando le aree di bassi valori di resistività che potenzialmente possono contenere il materiale archeologico. Inoltre, la profondità massima dei depositi si crede di essere circa 4-5 metri sulla base delle immagini di resistività Polo-Polo, mentre la profondità massima d’indagine era di circa 8 metri, confermata anche dai dati sismici.  Confrontando i dati della resistività, sismici e archeologici, è possibile caratterizzare meglio la natura del riempimento e di localizzare diversi processi post-deposizionali coinvolti nella creazione del deposito. Laser scanner e rilievo fotogrammetrico hanno fornito il modello tridimensionale della grotta e delle colonne stratigrafiche ad alta risoluzione, che rappresentano il punto di partenza per la modellazione dei dati geofisici. Inoltre, l'indagine dettagliata delle superfici, come pareti della grotta, colonne stratigrafia e le sezioni di scavo, hanno un aspetto importante per la documentazione archeologica, future ricerche, l'interpretazione e l'archiviazione del sito.
The study is focused on implementation of integrated, three-dimensional geophysical and topographical surveys investigation of Early Prehistoric sites on the example of Fumane Cave (Verona, Italy). The methods applied include electrical resistivity tomography (ERT), seismic surface waves (HVSR), laser scanner and photogrammetry. The study involved the use of two resistivity arrays, Wenner-Schlumberger (WSC) and Pole-Pole (PP), both for the shallow resolution in the first 2-3 meters of the deposit and to get information about the total depth and the position of bedrock. Seismic surface-waves may show amplitude resonances at certain frequencies depending on the thickness and elastic parameters of near-surface layers seismic velocity variations and can provide information about the geometry of the bedrock. Two and three-dimensional inversion models provided suggestive resistivity images, that provided detailed information about deposit’s texture spatial characteristics, indicating areas of low resistivity values where potential archaeological materials may be found. Moreover, the maximum depth of the deposits is believed to be around 4-5 m based on the Pole-Pole resistivity images, while the maximum depth of investigation was around 8 meters confirmed by seismic data. Furthermore, by comparing the resistivity, seismic and archaeological data, it is possible to characterise better the nature of sedimentary infill and to locate different post depositional processes involved into the creation of cave deposit. Laser scanner and photogrammetric survey provided georeferenced, high-resolution, three-dimensional, morphologically accurate model of the cave and stratigraphy profiles, serving as a starting point for the modelling of the geophysical data. Furthermore, the detailed survey of the surfaces, such as cave walls, stratigraphy sections and excavation sections, is an important aspect of archaeological data collection, investigation, interpretation and archiving of the site.  
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Gagnon, Éric. "A three-dimensional laser range scanner based on the self-mixing effect in a laser diode." Thesis, University of Ottawa (Canada), 1997. http://hdl.handle.net/10393/9895.

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In the last few decades, the field of artificial vision has witnessed an overwhelming growth through academic research and increasing industry demands. One of the more exciting and promising developments in the field has taken form in the 3D vision paradigm. With the advent of 3D vision, the possibility to directly map in three dimensions the shape of an object has opened a wealth of new possibilities. The purpose of this work is to present the theory and design of a low-cost, portable and accurate 3D laser range scanning system. The system allows direct acquisition of 3D images from a scene. The proposed 3D imaging method uses a laser beam for measuring the distance to a target in a fixed point and computing its (X, Y, Z) coordinate in space. Through deflection of this beam using small motorized mirrors, a distant surface may be scanned into a full 3D range image. Unlike conventional ranging systems, the present design uses a single semiconductor laser diode serving as both a laser source and detector. Laser ranging is achieved through frequency modulation of the laser with time-of-flight coherent detection, based on the self-mixing effect in a laser diode. This allows for unambiguous range measurement capabilities over several meters. The benefits of this sensing approach over existing laser-based systems are numerous, and include: (1) Very low cost solution to the ranging problem. (2) No need for external optical sensing elements. (3) Coaxial source and detector configuration eliminates shadowing problems. (4) Coherent detection yields constant ranging error over useful workspace. (5) Velocity and range information available from a single measurement. (6) Interferometric scale measurements possible in fixed-frequency regime.
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Heathcote, Alan D. "The dual development of an optical tomographic scanner and three dimensional gel dosimeter for complex radiotherapy verification." Thesis, University of Hull, 2008. http://hydra.hull.ac.uk/resources/hull:764.

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The state-of-the-art radiotherapy delivery treatments available today require that the intended dose distributions delivered are verified by volumetric gel dosimetry. The development of tissue equivalent gel dosimeters that provide an integrated assessment of the dynamic treatments, are primarily imaged with Magnetic Resonance Imaging (MRI). This thesis describes the dual development and assessment of an optical tomographic scanner and normoxic gel dosimeter. MRI centers are currently limited in both time and resources in providing the routine imaging necessary for treatment verification. An alternative bench top imaging modality has been designed, built and developed to provide both complementary and comparable observations to MRI. It is hoped that this cost effective optical imaging system could alleviate this technological reliance. The optical tomography scanner is evaluated from a series of investigations into the capabilities and limitations of optical tomographic imaging used in conjunction with gel dosimetry. Previously, the manufacture of gel dosimeters required anoxic environments in which the presence of oxygen in the dosimeter is limited. This requirement limited the production of gel dosimeters to chemistry laboratories that possessed the required technical expertise. MRI and optical imaging have been used to investigate the properties, dose response and the batch-to-batch reproducibility of a normoxic MAGIC gel dosimeter. The results obtained are encouraging having shown successfully reconstructed optical images obtained from various dose distributions delivered to the MAGIC gel dosimeter.
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Longo, Federico. "Three-dimensional computation of femoral canine morphological parameters: from the theory to the surgery application." Doctoral thesis, Università degli studi di Padova, 2017. http://hdl.handle.net/11577/3426322.

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The present research was envisioned as a project defined by multiple studies that are strictly correlated each other. The report of the birth, development and practical application to the diagnostic and surgery fields of a novel 3D approach for the computation of femoral measurements was the first aim. Moreover, in the authors’ purpose the description of the translational value of the proposed procedure enhanced with its plausible utility to the daily practice of orthopaedic surgeons, represented another focal point. In this sense, the research started from the validation of the 3D assessment of femoral morphometric parameters. Veterinary literature reports tons of papers describing several methodologies for obtaining femoral measurements through different diagnostic techniques. Furthermore, bibliography presents lot of angles values that are currently adopted and considered as reference parameters for most of the corrective osteotomies. Additionally, in the recent past an increased emphasis on 3D approach grown but little if any attention was devoted to 3D measurements. This trend represented in the authors’ mind the gap with the current knowledge and, thus, an area to be deeply investigated. Indeed, to the best of author knowledge, there were no papers documenting the assessment of 3D femoral axes and angles in veterinary medicine, with no 3D protocol described. In addition, currently available canine femoral measurements related to frontal, sagittal and transverse deformities have only been computed in bi-planar projections, whether acquired from 2D or 3D imaging models. Therefore, starting from the accepted human methods and from the features definition in veterinary literature, we proposed a new approach. The first study was designed to define a 3D methodology, introducing a consistent and quantitative method for the assessment of femoral morphometric parameters in 3D geometrical models. To validate the proposed approach, accurate geometric data were necessary and, therefore, we opted for meshes obtained by a 3D scanner, instead of CT images. Once the validation of the was stated, our focus was directed towards the evaluation of the precision of the proposed 3D protocol. The validation of a novel diagnostic test requires verification of the repeatability, defined as the strength of agreement between repeated measurements of the same samples performed from one examiner, and the reproducibility as well, that express the same variance but between a group of observers. Furthermore, the accuracy of the measurements indicates how close the measurements took with the investigated technique to a true value (gold standard). Therefore, a second project was designed to test the precision of three diagnostic techniques, two largely diffuse (Rx and TC) one recently introduced in veterinary (3D), for the measurement of femoral angles. The second purpose of this study was the investigation of the potential application of the algorithm implemented in a computer-aided-design (CAD) software, using CT data. Considering that for the first study we worked with 3D scanner data, the main aim at this point of the research was represented by the enhancement of the presented 3D protocol for diagnostic purposes. In the author opinion, changing the source of data was necessary because of the availability of CT and MRI equipment in veterinary practice. Finally, the last goal of this project was the translation of the application of 3D computation to the surgical field. The current research contemplates the fact that the augmented interest on 3D computation is not only relevant for diagnostic reasons, but also for surgery. Thus, the correlation between the diagnostic utility of the 3D approach and its plausible practice for surgery purposes was the object of the final study. The starting point was suggested by veterinary literature that reports in few papers the development and application of surgical devices used to perform assisted-correction of bone deformities. These surgical tools are designed through 3D geometrical models and act both as precise intraoperative localizers of osteotomy corrective landmarks and surgical saw guides. Three-dimensional assessment of a bone conformation may improve the understanding and evaluation of bone deformities and occurring joints malalignment. In this sense, the localization of the CORA as well as the accuracy of the orientation of the osteotomy-cutting plane may be significantly upgraded through a 3D approach.
La tesi di dottorato presentata è stata concepita nell’ambito di un più ampio progetto che comprende molteplici studi tra loro intrinsecamente correlati. L’obiettivo principale del lavoro consiste nella descrizione delle basi teoriche, sviluppo nonchè applicazione pratica nel campo della diagnostica per immagine e chirurgia di un nuovo protocollo 3D utilizzato per la misurazione di angoli nel femore del cane. Lo scopo successivo è stato quello di descrivere il valore traslazionale della procedura analitica qui presentata. Il primo passo dell’intera ricerca è rappresentato dalla validazione della metodologia. Un nuovo algoritmo sviluppato consente, per mezzo di un CAD software di comune utilizzo (Rhinoceros), di eseguire la computazione di angoli in 3D. Il secondo step ha previsto la verifica della ripetibilità e della riproducibilità di tale metodica che è stata comparata con quelle più comuni effettuate con radiografia e Tac. Infine, con l’ultimo studio abbiamo traslato le basi teoriche in applicazione chirurgica andando a creare, per mezzo dell’algoritmo elaborato, delle dime chirurgiche. Questi strumenti intra-operatori sono molto utili durante la chirurgia per le osteotomie correttive in quanto si accoppiano perfettamente nel punto di deformità e consentono di guidare l’osteotomia dell’osso.
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DI, VECE LUCA. "A study into the clinical effects of the rapid palatal expansion." Doctoral thesis, Università di Siena, 2017. http://hdl.handle.net/11365/1022996.

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This thesis contains different studies on the effects of the rapid palatal expansion.The purpose of this thesis is to investigate some of the effects of palatal expansion which are still unaddressed in literature. The first part of the thesis, after a brief introduction to the transverse maxillary contraction and palatal expansion, will outline the results of clinical trials that relate to the non-orthodontic effects that palatal expansion may have on: cervical vertebrae, posture and upper airways.The second part will show the first results, from an orthodontical point of view, of a multicentric randomized clinical trial designed to analyze the possible different effects of palatal expander anchored on deciduous or permanent teeth.
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Laforge, Travis. "Specialization in Small-Scale Societies: The Organization of Pottery Production at Kolomoki (9ER1), Early County, Georgia." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4115.

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Investigating the organization of production systems can reveal much about a society, in particular how resources and labor were allocated, and the influence that economic, political, social, and ceremonial institutions had on the production process. Interpreting the nature of specialized production is useful for understanding how production was organized. In turn, the degree of standardization exhibited by the goods being produced is used to determine the nature of specialization. While archaeological research regarding specialized production has expanded over time to incorporate a wide range of societies, such research is often focused on complex societies. The research presented here focuses on the small-scale, or non-stratified, community that once inhabited the Kolomoki site, a Middle to Late Woodland period site in Early county, Georgia. This thesis utilizes a three-dimensional laser scanner to document Weeden Island pottery from Kolomoki. The digital images created by the scanner were used to measure incising and punctation marks. The measurements were then analyzed in order to determine the extent of standardization among the decorative attributes. Results suggest that standardization varies among different subsamples of pottery. However, the overall degree of standardization is relatively low, thus suggesting that specialized production may not have existed, or was very limited, at Kolomoki. Despite the limited extent of standardization among the decorative attributes, the results of this research, especially in conjunction with previous research, suggest that some pottery may have been afforded special attention during the production process. In particular, pottery from mound proveniences, and socially valued goods, notably sacred and prestige items, demonstrate higher degrees of standardization. This leads to the conclusion that the production of Weeden Island pottery was likely influenced by ritual and ceremonial activity within the Kolomoki community. This thesis contributes to a greater understanding of specialization in non-stratified Woodland period societies in the southeastern United States.
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Books on the topic "Three-dimensional scanner"

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Elberink, Sander Oude. Acquisition of 3D topography: Automated 3D road and building reconstruction using airborne laser scanner data and topographic maps. Delft: NCG, Netherlands Geodetic Commission, 2010.

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Green, D. A. The BIRIS server: Integration of a three-dimensional range sensor into a harmony-based realtime architecture. Ottawa: National Research Council of Canada, 1992.

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Slob, Siefko. Automated rock mass characterisation using 3-D terrestrial laser scanning. [Enschede, Netherlands]: ITC, 2010.

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National Aeronautics and Space Administration (NASA) Staff. Application of a Laser Scanner to Three Dimensional Visual Sensing Tasks. Independently Published, 2018.

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Book chapters on the topic "Three-dimensional scanner"

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Mahjoubfar, Ata, Claire Lifan Chen, and Bahram Jalali. "Three-Dimensional Ultrafast Laser Scanner." In Artificial Intelligence in Label-free Microscopy, 21–29. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-51448-2_4.

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Pérez, Alex, Javier Rojas, and Gustavo Caiza. "Comparative Study of Sensors Applied to a Three-Dimensional Scanner." In Advances in Intelligent Systems and Computing, 63–73. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32033-1_7.

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Han, D., C. N. Rolfsen, E. Erduran, E. E. Hempel, H. Hosamo, J. Guo, F. Chen, and C. Ying. "Application of phase three dimensional laser scanner in high altitude large volume irregular structure." In ECPPM 2021 – eWork and eBusiness in Architecture, Engineering and Construction, 361–66. London: CRC Press, 2021. http://dx.doi.org/10.1201/9781003191476-50.

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Husain, Arshad, and R. C. Vaishya. "An AHP Based Automated Approach for Pole-like Objects Detection Using Three Dimensional Terrestrial Laser Scanner Data." In Communications in Computer and Information Science, 692–703. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-10-8660-1_52.

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Knisely, J. P. S., L. Liu, M. J. Maryanski, M. Ranade, R. J. Schulz, and J. C. Gore. "Three-Dimensional Dosimetry for Complex Stereotactic Radiosurgery Using a Tomographic Optical Density Scanner and BANGTMPolymer Gels." In Radiosurgery 1997, 251–60. Basel: KARGER, 1997. http://dx.doi.org/10.1159/000062284.

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Batra, Varun, and Vijay Kumar. "Developments in Three-Dimensional Scanning Techniques and Scanners." In Lecture Notes in Mechanical Engineering, 59–88. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8304-9_5.

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Haneberg, W. "Directional roughness profiles from three-dimensional photogrammetric or laser scanner point clouds." In Rock Mechanics: Meeting Society's Challenges and Demands, 101–6. Taylor & Francis, 2007. http://dx.doi.org/10.1201/noe0415444019-c13.

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Achenbach, Stephan, Jonathan Leipsic, and James Min. "New technical developments in cardiac CT: Anatomy, fractional flow reserve (FFR), and machine learning." In The ESC Textbook of Cardiovascular Imaging, edited by José Luis Zamorano, Jeroen J. Bax, Juhani Knuuti, Patrizio Lancellotti, Fausto J. Pinto, Bogdan A. Popescu, and Udo Sechtem, 145–58. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780198849353.003.0011.

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Computed tomography (CT), in the context of cardiac imaging, faces numerous challenges. The heart is a complex, three-dimensional organ, which moves very rapidly and has small dimensions. The coronary arteries, the main target of cardiac CT imaging, are especially difficult to visualize by any non-invasive technique. All the same, technology progress has made the use of CT for cardiac and coronary diagnosis possible. For selected applications, including ruling out coronary artery stenoses in low-risk individuals, CT has become a clinical tool. This chapter describes the progress of CT technology, from the first commercially available CT scanner that permitted visualization of the heart with high temporal and spatial resolution in the late 1980s, to today’s incarnations that utilize radiomics and artificial intelligence.
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Corner, Brian, Peng Li, Megan Coyne, Steven Paquette, and Douglas McMakin. "Comparison of Anthropometry Obtained from a First Production Millimeter Wave Three-Dimensional Whole Body Scanner to Standard Direct Body Measurements." In Advances in Human Factors and Ergonomics Series, 233–39. CRC Press, 2010. http://dx.doi.org/10.1201/ebk1439835111-27.

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Corner, Brian, Peng Li, Megan Coyne, Steven Paquette, and Douglas McMakin. "Comparison of Anthropometry Obtained from a First Production Millimeter Wave three-Dimensional Whole Body Scanner to Standard Direct Body Measurements." In Advances in Human Factors and Ergonomics Series, 233–39. CRC Press, 2010. http://dx.doi.org/10.1201/ebk1439835111-c26.

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Conference papers on the topic "Three-dimensional scanner"

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Blanche, Pierre-Alexandre, Colton Bigler, Joshua McDonald, and Zachary Rovig. "Holographic Angular Amplification for LIDAR Scanner." In Digital Holography and Three-Dimensional Imaging. Washington, D.C.: OSA, 2019. http://dx.doi.org/10.1364/dh.2019.th3a.24.

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Viganò, Nicola, Felix Lucka, Ombeline de La Rochefoucauld, Sophia Bethany Coban, Robert van Liere, Marta Fajardo, Philippe Zeitoun, and Kees Joost Batenburg. "Towards X-ray Plenoptic Imaging: Emulation with a Laboratory X-ray Scanner." In Digital Holography and Three-Dimensional Imaging. Washington, D.C.: OSA, 2021. http://dx.doi.org/10.1364/dh.2021.dth4f.2.

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Sunthankar, S. "Three-dimensional solid object laser scanner." In Applications in Optical Science and Engineering, edited by David P. Casasent. SPIE, 1992. http://dx.doi.org/10.1117/12.131626.

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Makino, Issei, and Nobuhiko Miki. "Three-dimensional Scanner for Multipath Fading Measurement." In 2020 International Conference on Information and Communication Technology Convergence (ICTC). IEEE, 2020. http://dx.doi.org/10.1109/ictc49870.2020.9289489.

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Mitsuji Monta, Kazuhiko Namba, and Naoshi Kondo. "Three Dimensional Sensing System Using Laser Scanner." In 2004, Ottawa, Canada August 1 - 4, 2004. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2004. http://dx.doi.org/10.13031/2013.16177.

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Yoshizawa, Toru, and Toshitaka Wakayama. "Three-dimensional profilometry system incorporating a MEMS scanner." In SPIE Optical Engineering + Applications, edited by Peisen S. Huang, Toru Yoshizawa, and Kevin G. Harding. SPIE, 2009. http://dx.doi.org/10.1117/12.825980.

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Lee, Changyeop, Wonseok Choi, Jeesu Kim, and Chulhong Kim. "Three-dimensional photoacoustic/ultrasound handheld scanner for clinical translation." In Photons Plus Ultrasound: Imaging and Sensing 2020, edited by Alexander A. Oraevsky and Lihong V. Wang. SPIE, 2020. http://dx.doi.org/10.1117/12.2544021.

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Aljasem, Khaled, Luc Froehly, Hans Zappe, and Andreas Seifert. "Integrated three-dimensional scanner for endoscopic optical coherence tomography." In SPIE Photonics Europe, edited by Hugo Thienpont, Peter Van Daele, Jürgen Mohr, and Hans Zappe. SPIE, 2010. http://dx.doi.org/10.1117/12.851644.

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Wawrzik, T., C. Kuhlmann, F. Ludwig, and M. Schilling. "Scanner setup and reconstruction for three-dimensional magnetic particle imaging." In SPIE Medical Imaging, edited by John B. Weaver and Robert C. Molthen. SPIE, 2013. http://dx.doi.org/10.1117/12.2006392.

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Gu, Tongzhao, Maohua Zhu, and Shaojun Fang. "Three-dimensional imaging system with holographic scanner and auxiliary reflectors." In Photonics Asia 2004, edited by Yunlong Sheng, Dahsiung Hsu, Chongxiu Yu, and Byoungho Lee. SPIE, 2005. http://dx.doi.org/10.1117/12.575670.

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Reports on the topic "Three-dimensional scanner"

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Gantzer, Clark J., Shmuel Assouline, and Stephen H. Anderson. Synchrotron CMT-measured soil physical properties influenced by soil compaction. United States Department of Agriculture, February 2006. http://dx.doi.org/10.32747/2006.7587242.bard.

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Methods to quantify soil conditions of pore connectivity, tortuosity, and pore size as altered by compaction were done. Air-dry soil cores were scanned at the GeoSoilEnviroCARS sector at the Advanced Photon Source for x-ray computed microtomography of the Argonne facility. Data was collected on the APS bending magnet Sector 13. Soil sample cores 5- by 5-mm were studied. Skeletonization algorithms in the 3DMA-Rock software of Lindquist et al. were used to extract pore structure. We have numerically investigated the spatial distribution for 6 geometrical characteristics of the pore structure of repacked Hamra soil from three-dimensional synchrotron computed microtomography (CMT) computed tomographic images. We analyzed images representing cores volumes 58.3 mm³ having average porosities of 0.44, 0.35, and 0.33. Cores were packed with < 2mm and < 0.5mm sieved soil. The core samples were imaged at 9.61-mm resolution. Spatial distributions for pore path length and coordination number, pore throat size and nodal pore volume obtained. The spatial distributions were computed using a three-dimensional medial axis analysis of the void space in the image. We used a newly developed aggressive throat computation to find throat and pore partitioning for needed for higher porosity media such as soil. Results show that the coordination number distribution measured from the medial axis were reasonably fit by an exponential relation P(C)=10⁻C/C0. Data for the characteristic area, were also reasonably well fit by the relation P(A)=10⁻ᴬ/ᴬ0. Results indicates that compression preferentially affects the largest pores, reducing them in size. When compaction reduced porosity from 44% to 33%, the average pore volume reduced by 30%, and the average pore-throat area reduced by 26%. Compaction increased the shortest paths interface tortuosity by about 2%. Soil structure alterations induced by compaction using quantitative morphology show that the resolution is sufficient to discriminate soil cores. This study shows that analysis of CMT can provide information to assist in assessment of soil management to ameliorate soil compaction.
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Yan, Yujie, and Jerome F. Hajjar. Automated Damage Assessment and Structural Modeling of Bridges with Visual Sensing Technology. Northeastern University, May 2021. http://dx.doi.org/10.17760/d20410114.

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Recent advances in visual sensing technology have gained much attention in the field of bridge inspection and management. Coupled with advanced robotic systems, state-of-the-art visual sensors can be used to obtain accurate documentation of bridges without the need for any special equipment or traffic closure. The captured visual sensor data can be post-processed to gather meaningful information for the bridge structures and hence to support bridge inspection and management. However, state-of-the-practice data postprocessing approaches require substantial manual operations, which can be time-consuming and expensive. The main objective of this study is to develop methods and algorithms to automate the post-processing of the visual sensor data towards the extraction of three main categories of information: 1) object information such as object identity, shapes, and spatial relationships - a novel heuristic-based method is proposed to automate the detection and recognition of main structural elements of steel girder bridges in both terrestrial and unmanned aerial vehicle (UAV)-based laser scanning data. Domain knowledge on the geometric and topological constraints of the structural elements is modeled and utilized as heuristics to guide the search as well as to reject erroneous detection results. 2) structural damage information, such as damage locations and quantities - to support the assessment of damage associated with small deformations, an advanced crack assessment method is proposed to enable automated detection and quantification of concrete cracks in critical structural elements based on UAV-based visual sensor data. In terms of damage associated with large deformations, based on the surface normal-based method proposed in Guldur et al. (2014), a new algorithm is developed to enhance the robustness of damage assessment for structural elements with curved surfaces. 3) three-dimensional volumetric models - the object information extracted from the laser scanning data is exploited to create a complete geometric representation for each structural element. In addition, mesh generation algorithms are developed to automatically convert the geometric representations into conformal all-hexahedron finite element meshes, which can be finally assembled to create a finite element model of the entire bridge. To validate the effectiveness of the developed methods and algorithms, several field data collections have been conducted to collect both the visual sensor data and the physical measurements from experimental specimens and in-service bridges. The data were collected using both terrestrial laser scanners combined with images, and laser scanners and cameras mounted to unmanned aerial vehicles.
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