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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Method for Synthesis of Three Dimensional Head with Single 2D Image

Yu, Yingfeng January 2005 (has links)
1 volume
2

Tissue thickness measurement tool for craniofacial reconstruction

Boddupalli, Hari Kiran G. January 1999 (has links)
Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains vii, 106 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 97-98).
3

Three dimensional (3D) forensic facial reconstruction in an Egyptian population using computed tomography scanned skulls and average facial templates : a study examining subjective and objective assessment methods of 3D forensic facial reconstructions

Abdou, Dalia Ahmed Selim Ali January 2018 (has links)
Forensic facial reconstruction can assist identification by reconstructing a face of the unknown person with the aim of its recognition by his/her family or friends. In the facial reconstruction approach adopted in this study, a 3D average face template was digitally warped onto a 3D scanned skull image. This study was carried out entirely on an Egyptian population, and was the first of its kind. Aims: This study aimed to demonstrate that 3D facial reconstructions using the novel methodology described could show significant resemblance to the faces corresponding to the persons in question when they were alive. Moreover, using techniques previously validated for facial reconstruction, the aim was to compare them to the method developed, and to assess approaches used to determine the accuracy of 3D facial reconstructions. Methods: Initially, a pilot study was conducted using a database of laser scanned skulls and faces. The faces were reconstructed using an average facial template generated by merging a number of faces of similar population, sex, and age. The applicability, as well as the main components of the facial reconstruction method, the single and average facial templates, and the facial soft tissue thickness measurements, were investigated. Furthermore, in the main study, the faces of computed tomography (CT) scanned heads of an Egyptian population were reconstructed using average facial templates. The accuracy of the reconstructed faces was assessed subjectively by face pool, and face resemblance tests, and objectively by measuring the surface distances between the real and reconstructed faces. In addition, a number of novel subjective and objective assessment methods were developed. These included assessment of individual facial regions using subjective resemblance scores, and objective surface distance comparisons. A new objective method, craniofacial anthropometry, was developed by taking and comparing direct measurements from the skull, and comparing the measurements from the real and reconstructed faces. The studied cases were ranked according to all subjective, and objective, tests, and statistically correlated. Results and Conclusions: The average facial templates showed a higher identification rate than the single face templates. The approach of facial reconstruction used in this thesis showed a comparable accuracy to many other facial reconstruction methods, yet was superior in terms of its applicability, transferability, and ease of use. In the face pool tests, the younger assessors were able to correctly identify the reconstructed faces better than older assessors. Furthermore, the identification rate by the forensic anthropology experts was higher than the non-experts. The former group showed the highest agreement between the observers in giving the resemblance scores. Although there was a significant rank correlation between the subjective and objective assessment tests, the subjective tests are influenced by the assessors' subjective characteristics (e.g., age, professional experience), thus making objective assessment more reliable. However, in situations where subjective tests are used, it is better to use the face resemblance tests and consult forensic anthropologists. Also, Craniofacial Anthropometry, particularly the craniofacial angles, can successfully indicate the accuracy of the facial reconstructions. Importantly, this study shows that certain facial regions, particularly the cheek and the jaw, are more reliable than other areas in the subjective and objective assessment of the facial reconstruction.
4

The face of Stonehenge: 3D surface scanning, 3D printing and facial reconstruction of the Winterbourne Stoke cranium

Nilsson, O., Sparrow, Thomas, Holland, Andrew D., Wilson, Andrew S. 19 August 2022 (has links)
No / Stonehenge is one of the world’s most iconic archaeological sites and yet we know relatively little about the people that created this important prehistoric monument. This chapter contributes to this narrative by reconstructing the face of a high-status male who was recovered during nineteenth-century excavation of a Neolithic Long Barrow. Situated in the barrow cemetery at Winterbourne Stoke, this site is important to the contextual setting and contemporary development of Stonehenge as a ceremonial and ritual centre. The chapter reports on the combination of digital bioarchaeology and visual heritage methods, together with forensic reconstruction, that transformed the physical remains of the individual into digital data that was manipulated for 3D printing; and subsequent anatomical and visual art interpretation to yield physical life-like characteristics. His facial features have been rebuilt on the 3D printed skull, muscle by muscle, to create a highly realistic face from the era. The aim of this project was to provide a tangible connection to the archaeology of the Stonehenge landscape and to the people that developed its ceremonial and ritual significance—narrowing the temporal distance through the emotional experience it means to gaze into the eyes of a Neolithic individual.
5

Validation using 3D CT of the new interpretation of Gerasimov’s nasal projection method for forensic facial approximation

Maltais Lapointe, Geneviève 13 August 2013 (has links)
Approximating the facial features for forensic facial approximation is challenging, especially the nose. Numerous methods have been published to position the tip of the nose in profile with variable results. Gerasimov’s two-tangent method is the most commonly used. However, a recent article published by Ullrich and Stephan (2011) states that the method was not properly performed and provides new guidelines. This research used a sample of CT scans from a Denmark population (N=66) to determined which of Gerasimov’s literal translation or Ullrich and Stephan’s (2011) new version of the two-tangent method is the most accurate. A combination of the two methods was also evaluated to determine the effect of each tangent independently, and the effect of intraobserver error. It was determine that the new guidelines result in smaller mean difference but no method can accurately position the tip of the nose due to the lack of experience from the practitioner.
6

Validation using 3D CT of the new interpretation of Gerasimov’s nasal projection method for forensic facial approximation

Maltais Lapointe, Geneviève 13 August 2013 (has links)
Approximating the facial features for forensic facial approximation is challenging, especially the nose. Numerous methods have been published to position the tip of the nose in profile with variable results. Gerasimov’s two-tangent method is the most commonly used. However, a recent article published by Ullrich and Stephan (2011) states that the method was not properly performed and provides new guidelines. This research used a sample of CT scans from a Denmark population (N=66) to determined which of Gerasimov’s literal translation or Ullrich and Stephan’s (2011) new version of the two-tangent method is the most accurate. A combination of the two methods was also evaluated to determine the effect of each tangent independently, and the effect of intraobserver error. It was determine that the new guidelines result in smaller mean difference but no method can accurately position the tip of the nose due to the lack of experience from the practitioner.
7

Data Driven Dense 3D Facial Reconstruction From 3D Skull Shape

Gorrila, Anusha 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This thesis explores a data driven machine learning based solution for Facial reconstruction from three dimensional (3D) skull shape for recognizing or identifying unknown subjects during forensic investigation. With over 8000 unidentified bodies during the past 3 decades, facial reconstruction of disintegrated bodies in helping with identification has been a critical issue for forensic practitioners. Historically, clay modelling has been used for facial reconstruction that not only requires an expert in the field but also demands a substantial amount of time for modelling, even after acquiring the skull model. Such manual reconstruction typically takes from a month to over 3 months of time and effort. The solution presented in this thesis uses 3D Cone Beam Computed Tomography (CBCT) data collected from many people to build a model of the relationship of facial skin to skull bone over a dense set of locations on the face. It then uses this skin-to-bone relationship model learned from the data to reconstruct the predicted face model from a skull shape of an unknown subject. The thesis also extends the algorithm in a way that could help modify the reconstructed face model interactively to account for the effects of age or weight. This uses the predicted face model as a starting point and creates different hypotheses of the facial appearances for different physical attributes. Attributes like age and body mass index (BMI) are used to show the physical facial appearance changes with the help of a tool we constructed. This could improve the identification process. The thesis also presents a methods designed for testing and validating the facial reconstruction algorithm.
8

Ansiktsrekonstruktion : Mannen från den medeltida kyrkoruinen S:t Hans, Visby / Facial reconstruction : The man from the medieval church ruin of St. Hans, Visby.

Gustavsson, Linnéa January 2019 (has links)
Facial reconstructions, like archaeology, consists of many layers that one must get through to understand the whole picture. The development of the methods that reconstructions rely on, occurred during the 20th century. By focusing on the various elements such as studies of tissue depth, chemical processes (DNA and isotope analysis), solid craftsmanship and the development of computer technology, researchers around the world have been able to build a method that can give us an extended understanding of history. However, a lot of opinions have risen for the subject, people begin to question it ́s accuracy and what the real purpose really is. Besides the reliability of facial reconstruction, the experience of how a facial reconstruction is perceived by another person is equally important, the ethical principles have been brought up to discussion because it involves human remains. Discussions may occur during cases when facial reconstructions are inevitable, one example could be with minority groups that have a different view on how a body should be handled and treated after death. These scenarios are more likely to develop in the identification in forensic contexts, but the problem may also increase in archaeological contexts if the remains are from more recent times and the individuals as a population group has suffered repression. Therefore, this paper aims to discuss such questions but also embark on a mission to perform a facial reconstruction of an individual from the medieval church of St. Hans and the challenges that may occur during the way. The American method used in this essay shows that you can get a good result by following the instructions and guidelines that are displayed in various books and articles.
9

Espessura de tecidos moles nos diferentes tipos faciais: estudo em tomografias computadorizadas cone-beam / Soft Tissue depth on different facial types: a Cone-Beam Computer tomography study

Beaini, Thiago Leite 08 October 2013 (has links)
A Reconstrução Facial Forense (RFF) é a área de estudos que visa estimar a face de um indivíduo a partir de um crânio. Médias de espessuras de tecidos moles em diferentes pontos cranianos, frequentemente obtidas em cadáveres por meio da punção com agulhas, são referencias utilizadas. Atualmente, alguns métodos digitais como a ressonância magnética, o ultrassom e a tomografia computadorizada do tipo Fan-Beam têm oferecido recursos técnicos que podem ser utilizados nas pericias forenses. A tomografia computadorizada Cone-Beam (TCCB), se diferencia de outras por permitir a aquisição de volume de pacientes sentados. No estudo da oclusão e ortodontia, é comum a atribuição de diferentes volumes e capacidade funcional à pacientes de diferentes tipologias faciais, por isso, objetiva-se estabelecer um método de mensuração da espessura tecidual, em exames de TCCB, em pontos utilizados em RFF verificando a existência de diferenças significativas na quantidade de tecidos moles entre tipos faciais. Um protocolo foi confeccionado para permitir que observadores efetuassem medições de tecidos moles em 32 pontos cranianos (10 sagitais e 11 bilaterais), comuns em trabalhos de RFF. A precisão do método, foi avaliada em testes de localização espacial dos pontos em 5 exames, correlação intraclasse intraobservador e interobservadores em 10 exames. O uso do computacional Osirx®, foi testado pela da correlação entre o software Nemotec®, em 25 exames. Testes visuais foram utilizados, como referência, comparando o protocolo com o método manual, realizando tomografia computadorizada de um crânio contendo marcações de resina composta. Os 100 sujeitos foram divididos em gênero, em tipos faciais verticais de face longa (FL), face curta (FC) e face normal (FN), e divididos em tipos faciais anteroposteriores: Padrão I, II e III. Estatisticamente, foram aplicados testes de normalidade e a diferença entre cada grupo foi testada. A amostra foi dividida em 50 homens: 13 FN, 29 FL e 8 FC, sendo 20 CL I, 14 CL II e 16 CL III. As 50 mulheres foram divididas em 16 FN, 24 FL e 10 FC, sendo 24 CL I, 18 CL II e 8 CL III. O método foi considerado adequado, uma vez que pouca experiência foi necessária para que dois observadores localizassem pontos com grau de precisão semelhante. As médias de correlação intraclasse foram consideradas fortes entre os programas (0,75) e entre observadores (0,8), e fortíssima no teste intraobservador (0,9). Os testes visuais apontaram grande coincidência entre o método manual e o digital com vantagem para o segundo devido às ferramentas computacionais disponíveis. As medidas entre homens e mulheres foram diferentes em vários pontos, sendo que o gênero masculino apresentou espessuras maiores, exceto os pontos laterais da órbita. Pouca diferença foi encontrada entre os grupos faciais, que justifique uma abordagem diferenciada entre eles. No entanto, características morfológicas podem ser percebidas, especialmente entre os indivíduos do gênero masculino. A espessura dos pontos sobre a mandíbula foram os que apresentaram maiores diferenças estatísticas, demonstrando que os indivíduos Padrão III e/ou face longa tem espessuras levemente mais delgadas que os de Padrão II e face curta. / Forensic facial reconstruction (FFR) is a research field that intends to estimate the face of an individual through a skull. Mean soft tissue thickness values, of different cranial landmarks, often obtained through needle puncture, are used as references. Lately, some digital methods, such as Magnetic resonance and Fan-beam Computer Tomography have been offering new resources to forensic analysis. Cone-Beam Computer Tomography (CBCT), differs from others, by allowing the volumetric acquisition of a sitting patient. In the study of occlusion and orthodontic, is usual to associate volume and functional features to different facial types, therefore the objective is to establish a CBCT soft tissue measuring method, for points used for FFR, verifying the existence of significant differences of soft tissue pattern in distinct facial types. A guideline was created to allow observers to measure soft tissue of 32 landmarks (10 sagittal and 11 bilateral), usually found in FFR researches. Precision was accessed through landmarks placing tests in 5 exams, inter-observers and intraobservers intraclass correlation in 10 exams. The use of the software Osirix® was supported by the comparison with Nemotec® in 25 exams. Visual tests were performed through a computer tomography from a skull with resin spheres placed through the manual approach. The 100 subject sample were divided into gender and then into vertical facial types of long face (LF), short face (SF) and normal face (NF), and in horizontal types: CL I, II, III. Normality statistical tests were applied and the difference between groups was tested. The sample was divided in 50 men: 13 NF, 29 LF, and 10 SF, as 20 were Class I, 14 CL II and 16 CL III. The 50 women were divided into 16 NF, 24 LF and 10 SF, as 24 were Class I, 18 CL II and 8 CL III. The method was considered adequate, as after little calibration was needed to allow observers to place landmarks with similar precision. The mean intraclass correlation was considered strong between software (0.75) and observers (0.8), and very strong on intra-observer (0.9). Visual tests pointed out good level of coincidence between manual and digital methods with advantage to the digital due to the available computer tools. The average measures differed between male and female gender, as thicker depths were observed in men in all landmarks, with exception to the Lateral Orbits. The small amount of difference, observed among facial types was considered insufficient to sustain the use of new reference charts. Nevertheless, morphological features could be noticed, especially among male subjects. The depth of landmarks placed over the mandible presented statistical differences, demonstrating that class III, and or long face facial types have less tissue in those areas than class II and short-faced patients.
10

Avaliação da acuracidade da reconstrução facial 3D por meio de fotografias antemortem de indivíduos previamente identificados / Evaluation of the accuracy of 3D facial reconstruction through ante-mortem photographs of previously identified individuals

Zeilmann, Patrícia Pereira 17 December 2013 (has links)
Este trabalho teve como objetivo avaliar, por meio de comparação com fotografias ante-mortem, a acuracidade da reconstrução facial forense manual e computadorizada de brasileiros adultos utilizando-se o método de Manchester. Foram reconstruídos os rostos a partir de 08 crânios, 04 femininos e 04 masculinos que foram exumados no Cemitério Municipal Necrópole do Campo Santo-Guarulhos/São Paulo. Esse estudo se justificou para possibilitar a utilização do método de Manchester considerando-se as profundidades de tecidos moles estabelecidas para brasileiros. Oito réplicas de gesso para a reconstrução manual, e oito modelos virtuais em 3D, obtidos por meio de tomografia para a computadorizada foram levados para o Centro de Anatomia e Identificação Humana da Universidade de Dundee/Escócia/Reino Unido. Utilizou-se argila para a manual e a tecnologia Sensable por meio do programa de computador FreeForm Modelling Plus, e do dispositivo tátil Phantom Haptic Desktop para a computadorizada. Avaliou-se a acuracidade das 16 reconstruções resultantes por meio de dois métodos: fotografias das reconstruções produzidas foram mostradas para 100 voluntários, que foram convidados a escolher o sujeito da fotografia em vivo quando incluído com outros cinco sujeitos aleatoriamente selecionados; e por meio de teste de semelhança, que comparou a fotografia da reconstrução com a do sujeito alvo lado a lado, o que foi feito também com dois sujeitos controle. Embora em ambos os testes os sujeitos alvo tiveram o melhor desempenho no número de acertos e no grau de semelhança, as reconstruções manuais obtiveram um melhor desempenho e o maior nível de acerto foi de 90% em um caso no teste de reconhecimento, enquanto na computadorizada foi de 81%. Este estudo demonstrou que o método de manchester em brasileiros, assim como o FreeForm Modelling Plus são ferramentas úteis e adequadas para o uso em reconstrução facial com níveis de sucesso muito significativos. / The aim of this study was to evaluate, by comparison with antemortem photographs, the accuracy of manual and computerized forensic facial reconstruction of adult Brazilians using the Manchester method. The faces were reconstructed from 08 skulls, 04 female and 04 male that were exhumed at the Municipal Cemitery Necropolis of Campo Santo-Guarulhos/Sao Paulo. This study is justified to allow the use of the Manchester method considering the soft tissue depths from Brazilian people. Eight plaster replicas made for manual reconstructions and eight 3D virtual models, obtained by tomography for computerized were taken to the Centre for Anatomy and Human Identification at the University of Dundee/Scotland/UK. Clay was used for the manual and the SensAble technology through the FreeForm Modeling Plus software and the tactil device Phantom Haptic Desktop for the computerized. The accuracy of 16 reconstructions resulting was evaluated by two methods: images of the reconstructions were produced and shown to 100 volunteers who were asked to choose the subject of photography in vivo when included with other five subjects randomly selected; and by the resemblance test, comparing the photograph of the reconstruction with the subject\'s target side by side, which was also done with two control subjects. Although in both tests the 08 subjects achieved the best results in the number of correct answers and in the degree of resemblance, the manual reconstruction achieved a better performance and the higher level of accuracy in one case was 90% in recognition test, while the computerized was 81%. This study showed that the Manchester method in Brazilians, as well as the FreeForm Modeling Plus are usefull and adequate tools for use in facial reconstruction with very significant levels of success.

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