National Repository of Grey Literature 45 records found  1 - 10nextend  jump to record: Search took 0.03 seconds. 
Polygon Meshes Reconstruction
Klíma, Ondřej ; Beran, Vítězslav (referee) ; Španěl, Michal (advisor)
The thesis is focussed on the reconstruction of a damaged skull represented by a polygonal model. The reconstruction is based on a statistical shape model of the skull. The thesis covers the registration of skulls by using a thin-plate spline method, aligning polygonal models by generalized procrustes analysis, the identification of missing parts of a skull by means of statistical shape models outliers analysis. Finally, missing parts of the skull are reconstructed and the accuracy of the reconstruction is estimated.
Forensic Identification of Child Faces
Klíma, Ondřej ; Španěl, Michal (referee) ; Beran, Vítězslav (advisor)
This thesis is focussed on children's faces comparison. Its aim is to create the application providing functions for photocomparison and ageing. Both these parts work with portrait photos of children. Photocomparison purpose is a metric expression of similarity of two portraits independently on their age. Ageing is a tool for the simulation of an individual's growing old on the photo. Principles of both functions are based on geometric morphometry methods, particulary on procrustes analysis and thin-plate spline aproximation.
Application of morphometric methods in anthropology
Pešek, Adam ; Eliášová, Hana (advisor) ; Šuláková, Hana (referee)
In last thirty years a new branch of comparative biology is growing rapidly, this branch is called the geometric morphometrics. Methods of geometrics morphometrics allow to gain and evaluate data about shape and size of studied object in 2D or 3D space. The character of input data divided methods used in geometric morphometric on method based on analysis of outlines and method based on analysis of landmarks. Many modern technologies like contact scanner, laser scanner or tps software are helping in data acquisition. The main conclusion of this bachelor work was exploring usability of methods of geometric morphometric in many cases in Anthropology. In many biological and mainly anthropological studies, geometric morphometric were applicated to compare shape variance and in studies of variability of shape. Common are studies of sexual dimorphism on human skeleton, ontogenetic developement of skeleton, disparity of sign on human skeleton among population and ethnicity or changes of these forms of structures in populations during time.
Facial development in children 6 to 12 years old: longitudinal study
Tošovská, Hana ; Velemínská, Jana (advisor) ; Zedníková Malá, Pavla (referee)
This study is based on evaluative longitudinal data of facial development in a group of children from 6 to 12 years. The research used three-dimensional models of the faces of 18 girls and 15 boys that were scanned at yearly intervals. These models were used to follow development of the face and its particular areas including analysis of variability (PCA). Developmental changes were observed for each gender separately as well as for the development of sexual dimorphism. Results were visualized by using superimposed color maps of average faces of a particular age group and maps depicting the statistically significant differences in individual areas. The presented data exhibited growth in the face of both genders, while slightly bigger changes in the form of the face were observed in the boys' samples. For girls and boys the most intensive growth was found in the direction of the width and height of the entire face and the nose, especially in the direction of length. These changes took place throughout the whole studied period of growth, yet more intensive growth was evident for girls beginning at age 10 years and for boys from 11 years onward. Shape changes also occurred with age for both genders: the face gradually narrowed, the cheeks flattened and a more retruded position of the forehead...
Ontogenetic changes of the face.
Benešová, Eliška ; Eliášová, Hana (advisor) ; Dvořák, Daniel (referee)
The human face is characterized by a combination of morphological characters, which are unique for each individual. These characters are subject to change during ontogeny influenced by age, pathological conditions, injuries. The aim of this diploma thesis was an observation of age changes in the face of individuals in the age range from one to eighteen. Resource material were black and white photographs of girls and boys. Analysis of age changes in facial area was performed using methods of geometric morphometrics, specifically thin plate spine (TPS). The shape analysis confirmed, that between age and face shape exists significant relationship. It was found, that is mainly due to significant changes in height and width ratios. Face extends and narrows, forehead height is reduced and lower jaw grows to lenght. Facial changes are also influenced by the sex of individuals, while for girls the overall growth in the face stopps about age of fifteen, for boys continues to the age of eighteen years. Keywords Geometric morphometrics, thin plate spline, ontogenetic development of the face, age changes.
Facial approximation: An assessment of the principles of the method and analysis of the craniofacial relationships
Zedníková Malá, Pavla ; Velemínská, Jana (advisor) ; Beňuš, Radoslav (referee) ; Krásničanová, Hana (referee)
This doctoral thesis is submitted in the form of scientific publications together with theoretical introduction. The present state of knowledge of facial approximation methods is presented in the introduction. Areas of application, principles of the method and classification of the methods according to medium used are briefly described. Accuracy and limits of the method are further described as they form a base of the research of this thesis. Simultaneous existence of multiple prediction guidelines, of which the accuracy is not known or published, is typical characteristic of the facial approximation method. The aim of this thesis was to assess the accuracy of the particular prediction rules for estimation of position and size of facial parts (eyes, nose, lips), and based on the results to recommend the most accurate and suitable guidelines for middle European population. An assessment of the strength of the association between craniofacial shape and the shape of soft tissues in the profile using geometric morphometric methods, and determination of the extent to which it might be possible to predict the latter from the former were the purpose of the second part of the research. Material for this study consisted of 87 lateral head cephalograms of a recent adult Central European population (52 males...
Variation in dragonfly wing venation with application of geometric morphometrics (Insecta: Odonata)
Přibylová, Petra ; Prokop, Jakub (advisor) ; Růžička, Jan (referee)
The pattern of wing venation in dragonflies (Odonata) bears a set of characters commonly used in systematics. The aim of this thesis is to identify the wing venation variability of dragonflies by various methods of geometric morphometric. The wing venation variability was examined on the level of suborder, family, species and also in respect to dimorphism through the principal component analysis (PCA), redundancy analysis (RDA) and centroid size. Data set consisting of images of 46 dragonfly species, belonging to 43 genera and 24 families was obtained from institutional entomological collections. The research carried out that Zygoptera have a large variety of wing contours. The wing venation variability of Epiprocta is shown primarily in the costa and node area. Between sexes there is no noticeable difference in shape or structure of the wing. The ratio between wing length and width and the pterostigma shape is dependent on dragonfly body size. Key words: Odonatoptera, Odonata, Epiprocta, Zygoptera, wing venation, variability, geometric morphometrics
Evaluation of ontogenetic development of the mandible using geometric morphometric methods
Kiebelová, Alena ; Velemínská, Jana (advisor) ; Brůžek, Jaroslav (referee)
During ontogeny there are a lot of changes in the entire human skeleton. This thesis deals with shape changes in the mandible, which are caused by genetic, hormonal, as well as mechanical factors. The most important mechanical factors influencing the shape of mandible are development of deciduous and permanent dentition and also development of masticatory muscles. 34 children mandibles of known age and 14 adult mandibles were analysed and compared for this thesis. Data were obtained by scanning coordinates of 36 landmarks using Microscribe G2X, and then were processed by software PAST and Morphologika2 using multivariate statistics (PCA, MANOVA). Geometric morphometrics is used for a detailed analysis of shape changes of the mandible. There is no difference between dental and chronological age. In conclusion, lower jaw narrows during growth, the body extends more in the region of third molars and the ramus grows mainly in the region of condylar process. Chin prominence also occurs during ontogeny. In the group of adult mandibles the variability is caused by coronoid process height and the body width. The hypothesis, that age groups are significantly different from each other, and therefore due to tooth mineralization there are marked shape changes, is confirmed.
Morphometric analysis of palatal surface in patients with unilateral complete cleft lip and palate.
Rusková, Hana ; Velemínská, Jana (advisor) ; Trefný, Pavel (referee)
Thesis deals with the study of palate morphology and variability of patients with UCLP, using modern methods of geometric morphometrics. Dental plaster casts of UCLP patients (average age 14,8) and the control group (average age 14,7) were used for evaluation. The models were scanned using a 3D scanner. For evaluation of total variability of patients with orofacial clefts, previously rated dental casts of BCLP patients (whose age ranged from 12,1 to 16,5) were also included. All patients were operated and treated at The Clinic of Plastic Surgery in Prague. The results are in accordance with literature, which describes the basic size and shape differences in the morphology of the palate in different types of clefts (e.g. narrowing of the palate in UCLP and BCLP and asymmetry of palatal vault in UCLP). Using "Dense correspondense models analysis" average surface models were computed and new informations about the shape and premaxila position were gained. Different location and slope of the palate in different types of clefts and within control group were detected by superimposition of average models and FESA. UCLP palate have typically asymetric palate vault with a maximum height in front of the cleft palate and at the back in the side without malformations. Variability of the shape of palate for each group...
Megasecoptera: morphology and taxonomy of newly discovered specimens from Upper Carboniferous of northern China (Insecta: Palaeodictyopteroida)
Pecharová, Martina ; Prokop, Jakub (advisor) ; Godunko, Roman (referee)
The extinct insect group of Palaeodictyopteroida (Insecta: Palaeoptera) comprised mainly phytophagous species and occurred from Upper Carboniferous to Upper Permian. Megasecoptera is one of several orders of belonging to this group. Although, the order Megasecoptera comprised over 20 described families, morphology of some body structures are insufficiently studied. The present thesis deals with evaluation of new material comprising the extensive set of 76 fossil insect specimens from the Upper Carboniferous (Bashkirian) of northern China. The fossils having excellent state of preservation of the wings and other body structures provide new insights concerning the external morphology of Megasecoptera. All studied specimens were attributed based on wing venation pattern into two known megasecopteran genera within families Brodiopteridae and Sphecopteridae. The aim of the present thesis is examine the morphology and variability of wing venation of two newly proposed species Brodioptera sp. n. and Cyclocelis sp. n. from site in northern China. In addition the following methods of geometric morphometrics based on landmarks were used for comparison of venational characters: a comparison of centroid size, procrustes analysis, principal component analysis and thin plate spline. Variability of wing venation...

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