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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 Spatial Analysis of Chachapoya Mortuary Practices at La Petaca, Chachapoyas, Peru

Epstein, Lori 01 January 2014 (has links)
Diversity of Chachapoya mortuary practices is not well understood archaeologically, even though the region has received some attention for the monumental constructions and visually striking mortuary complexes located high on open cliff faces. This may be due to the difficult accessibility and often poor state of preservation consistent with many Chachapoya mortuary and occupation sites. This thesis reconstructs mortuary practices at La Petaca in the Chachapoyas region of Peru, applying paleodemographic and GIS methodological approaches to facilitate and improve the bioarchaeological study of commingled skeletal remains in an open, disturbed communal funerary context. Research focused on SUP CF-01, a natural cave context utilized as a group burial. The sample of human remains retrieved from SUP CF-01 (n= 8182) estimated an MNI of 43 adults and 12 juveniles, including a range of demographic categories. By employing a total station to record the cave structure, and a GIS to analyze the deposit of commingled remains, this thesis was able to measure the distances between paired elements and to explore possible post-depositional practices that could have created this commingled and disturbed deposit. This bioarchaeological analysis incorporating demographic and spatial analysis indicated that this collective burial was a primary context, and most likely a result of a gradual accumulation of complete bodies and movement of later skeletonized elements to make room for successive burials. When compared to other mortuary contexts at this complex, including a comparative secondary cave context and over 120 constructed mausoleums, it appears that all community members were included in the mortuary practices at this complex.
2

An investigation into bilateral asymmetry of the appendicular skeleton of the adult human and its use in physical and forensic anthropology

Garrido Varas, Claudia E. January 2013 (has links)
The aim of this study was to establish whether the asymmetry of bilateral elements of the skeleton is useful for the reassociation of paired elements in the analysis of commingled skeletal remains; particularly addressing the forensic scenario of Chilean Human Rights cases. The asymmetry of the appendicular skeleton of the modern adult Chilean population was investigated in its morphological aspect, using both traditional anthropometry and geometric morphometrics. The sample was selected from the Colección Subactual de Santiago, housed in the University of Chile, Santiago, Chile, with N= 131 (69 males and 62 females). The traditional metric analysis of size and the geometric morphometric analysis of shape showed that there was a significant difference between sides in both sexes with a strong component of directional asymmetry. Mean metrics and ranges of asymmetry were established, contributing to the characterization of this population. A method to pair match elements from commingled settings, which is a combination of metric ranges of asymmetry and principal component analysis of shape variables, was created resulting in 95% accuracy when pair matching the humerus, radius, femur and tibia. This constitutes an important contribution to the analysis of shape in forensic contexts due to its strong mathematical component, objectivity and repeatability.
3

Caractérisation expérimentale et modélisation à l’échelle mésoscopique du comportement de tissus 3D de mèches comélées / Experimental characterization and modeling at the mesoscopic scale of the behavior of 3D fabrics of commingled yarns

Rocher, Jean-Emile 18 November 2014 (has links)
Cette thèse s’inscrit dans le cadre du projet européen 3D-LightTrans ayant pour objectifs la fabrication à grande à échelle et à bas coût de pièces composites. Pour parvenir à ces objectifs, des semi-produits sous forme de tissus 3D de mèches comélées ont été réalisés. Le but de ces travaux est de caractériser le comportement mécanique de ces tissus en vue d’analyser leur formabilité et d’être en mesure de prédire leur comportement pendant les processus de mise en forme utilisés lors de la fabrication des pièces composites. Le premier objectif de ces travaux était de caractériser expérimentalement le comportement mécanique des tissus 3D. Après avoir effectué un état de l’art ayant permis de définir les types et paramètres d’essais à utiliser pour la caractérisation du comportement des tissus, l’analyse des résultats de ces différents essais a permis de mettre en évidence les spécificités du comportement des tissus 3D. Le deuxième objectif des travaux était de modéliser le comportement des tissus par une approche numérique. Le choix s’étant porté sur une approche à l’échelle mésoscopique, le comportement mécanique des mèches comélées a été caractérisé expérimentalement. Les limitations du logiciel GeoFab quant à son utilisation pour la génération de modèles CAO de mailles élémentaires de tissus 3D ont été identifiées. Des améliorations permettant de répondre à ces limitations ont été proposées et leur faisabilité démontrée. Un modèle CAO d’une sous partie de la maille élémentaire d’un des tissus a alors été généré. Après avoir modélisé le comportement des mèches comélées en se basant sur les résultats de leur caractérisation expérimentale, des premières simulations éléments finis ayant permis d’obtenir des résultats encourageants ont été réalisés. / This thesis is part of the European project 3D-LightTrans whose objectives are the large scale and low-cost manufacturing of composite parts. To achieve these goals, semi-finished products in the form of 3D fabrics of commingled yarns were produced. The purpose of this work is to characterize the mechanical behavior of these fabrics in order to investigate their formability and be able to predict their behavior during the forming processes used for the manufacturing of composite parts. The first objective of the work was to characterize experimentally the 3D fabrics mechanical behavior. A state of the art was realized in order to define the types and test parameters to use. The analysis of these test results allowed to highlight the specific 3D fabrics mechanical behaviour. The second objective of the work was to model the fabrics behavior using a numerical method. A mesoscopic scale approach having been selected, experimental characterization of the commingled yarns mechanical behavior was necessary. Then, GeoFab software limitations on its use for the generation of CAD models of 3D fabrics unit cells were identified. Improvements to address these limitations have been proposed and their feasibility was demonstrated. A CAD model of a sub part of one of the fabrics unit cell was then generated. After having modeled the commingled yarns behaviour using experimental results, finite element simulations were performed on fabric CAD model and first encouraging results were obtained.
4

The overall biological profile of anatomized remains from the Winchester site

Borreson, Bailey 26 January 2024 (has links)
The following research examined the overall biological profile of an anatomized human skeletal assemblage discovered in Winchester, Massachusetts (Middlesex County) in 2020. This assemblage was discovered during construction of a private house in a suburban neighborhood. In addition, this project examined the history of medical teaching specimens and how this new collection connected to the anthropological understanding of this history. For centuries, marginalized individuals, including Black people, poor people, and criminals, were utilized as the cadaver supply for medical schools. The author examined the general biological profile, including sex, age, population affinity, and stature, of the Winchester assemblage. Since none of the fragmented postcranial bones were able to be matched to particular individuals, these estimations served as a profile for the general population of the Winchester assemblage. The skulls were the only parts of the sample that could be treated as specific individuals. Craniofacial nonmetric traits were observed as well as postcranial aspects of the skeleton. The total number (NISP) of adult remains was 14,469. The MNI of the adult remains was 35 based on the left femora. The author hypothesized that the majority of the remains would consist of male individuals, and the age profile would reflect the average age at death during the mid-1800s, which was about 20-40 years old. In addition, it was hypothesized that the majority of individuals would be of Black population affinity, which might indicate that the remains were robbed from Black cemeteries. The majority of the assemblage was indeed comprised of males. Specifically, 60.5% of the pubic symphyses and 58.8% of the greater sciatic notches analyzed were determined to be male. The general average age at death of the sample was 23 to 45 years old. Estimation of population affinity of the sample was attempted; however, the results were not compelling due to the fragmentation of the remains and limited ability to reconstruct crania. The stature of the remains was estimated to range from 58.1 to 69.9 inches or 4 feet 10 inches to 5 feet 10 inches. This biological profile was compared to the demographics of Middlesex County, Massachusetts, and the United States presented by the 1850 U.S. Census and data from the military during that time. The Winchester adult remains had more males than females, similar to the sex representation in Massachusetts’ poorhouses, penitentiaries, jails, and houses of correction during 1850. Unlike these institutions, the general population of Middlesex County had more females than males. The 1850 Census indicates that the majority of individuals in Massachusetts’ poorhouses, penitentiaries, jails, and houses of correction were 24 years and older, which aligns with the estimated aged range for the Winchester adult remains. White and Black individuals were the only population affinities compared in the 1850 Census, and there were significantly more White individuals. The average height of a White male in the US military was 63.7 inches, which aligned with the general stature interval of 58.1 to 69.9 inches for the adult Winchester remains. Future research, including DNA and isotope analyses, could provide further insights into the origins of these individuals discovered at this site.
5

A Paleodemographic Analysis of a Sample of Commingled Human Skeletal Remains at Ohio University

Kincer, Caroline D. 06 July 2018 (has links)
No description available.
6

Identifying cohorts using isotope mass spectrometry: the potential of temporal resolution and dietary profiles

Beaumont, Julia, Bekvalac, J., Harris, Sam, Batt, Catherine M. 14 February 2021 (has links)
Yes / Archaeological skeletal material from most sites represents a cross-sectional, opportunistic sample of the burials. These are influenced by the proportion and area of the site which is excavated, the taphonomic conditions and survival of tissues. This may not be representative of the population, and in an attritional cemetery may represent a long period of use, during which humans will have differing life-courses. Here we describe a commingled skeletal assemblage, the only human remains recovered from the historically significant medieval site of St Stephen’s Chapel, Palace of Westminster, London. Using carbon (δ13C) and nitrogen (δ15N) stable isotope ratios of bulk bone collagen and incremental dentine to investigate dietary life histories from 5 individuals, we combine the evidence with radiocarbon dating to assign them to two different temporal cohorts.
7

Application of commingled thermoplastic composites on an airline seat backrest

Mattheyse, Richard 12 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Thermoplastic composites (TPCs) have shown significant advantages over thermosetting composites. They have only been put into use recently and global knowledge in TPCs is often proprietary, therefore a study into the application, processing and properties is of importance. The aim of the study is to contribute knowledge in TPCs for South African industry and academic institutions. This thesis studies continuous fibre reinforced thermoplastics (CFRTPs), focussing on the autoclave processing of commingled CFRTPs. A literature study provided background knowledge to CFRTPs regarding processing techniques and mechanics. Flexural testing and impact testing were performed on a variety of CFRTPs and thermosetting composites (TSCs). These tests were performed to further understand CFRTPs as well as to compare CFRTPs and TSCs. The flexural testing revealed that CFRTPs have comparable strength and stiffness to the TSCs that were tested. They also revealed that pre-consolidated sheets showed better and more consistent properties than sheets made from commingled fabric. The impact testing revealed that the tested CFRTPs and TSCs had similar impact resistance even though thermoplastic composites are supposed to be more impact resistant. The tests also showed that thick unreinforced thermoplastics had much higher impact resistance than the reinforced materials. Manufacturing experiments were performed to establish sound processing methods of CFRTPs. It was realised here that the high temperatures required to process the materials require specific processing consumables and tooling. The experiments began by processing flat panels in a convection oven with vacuum bagging techniques. They then progressed to autoclave processing of parts with complex geometry. An airline seat backrest was chosen as the case study in the application of CFRTPs. This application requires structural strength and stiffness and also has strict fire, smoke, toxicity and heat release (FSTH) requirements. Its geometry was sufficiently complex to demonstrate the use of commingled CFRTP material. Backrests were made from both CFRTPs and TSCs so that a comparison could be made between the two types. The backrest was modelled using finite element methods (FEM) to determine an adequate lay-up. This lay-up was then used for both the CFRTP and TSC backrests to ensure similarity between the backrests of both materials. LPET (modified polyethylene terephthalate) was the chosen thermoplastic matrix as it was more attainable than PPS (polyphenylene sulphide) CFRTPs. The backrests of both materials were manufactured in an autoclave with a vacuum bag method and then assembled using adhesives and bonding jigs. Testing revealed that the stiffness and mass of the CFRTP backrests were very similar to the epoxy backrests. This implies that commingled CFRTPs can replace the use of TSCs in similar applications. A basic cost comparison was also performed to compare the manufacture of CFRTP backrests to TSC backrests. Further work is needed to optimise processing time of these materials to make them more competitive with TSCs. The processing time of commingled materials will probably never be as quick as that of press formed pre-consolidated sheets. Their ability to be formed into more complex parts does however make their use advantageous. / AFRIKAANSE OPSOMMING: Termoplastiese saamgestelde materiale (Engels: thermoplastic composites (TPCs)) toon beduidende voordele bo termoverhardbare saamgestelde materiale. Hulle word eers sedert onlangs benut en algemene kennis in TPCs is dikwels patentregtelik, dus is ’n studie van die aanwending, prosessering en eienskappe daarvan van belang. Die doel van hierdie studie is om ’n bydrae te lewer tot die kennis van TPCs vir die Suid-Afrikaanse industrie en akademiese instellings. Hierdie tesis ondersoek kontinue veselversterkte termoplastieke (Engels: continuous fibre reinforced thermoplastics (CFRTPs)) en fokus op die outoklaafprosessering van vermengde (Engels: commingled) CFRTPs. ’n Literatuurstudie het die agtergrondkennis rakende die prosesseringstegnieke en meganika van CFRTPs verskaf. Buigtoetsing en impaktoetsing is op ’n verskeidenheid CFRTPs en termoverhardbare saamgestelde materiale (Engels: thermosetting composites (TSCs)) uitgevoer. Hierdie toetse is uitgevoer om CFRTPs beter te verstaan asook om CFRTPs en TSCs te vergelyk. Die buigtoetsing het onthul dat CFRTPs ooreenstemmende sterkte en styfheid het as die TSCs wat getoets is. Dit het ook getoon dat vooraf-gekonsolideerde plate beter en meer konsekwente eienskappe getoon het as plate wat van vermengde materiaal gemaak is. Die impaktoetsing het onthul dat die CFRTPs en TSCs wat getoets is soortgelyke impakweerstand gehad het, selfs al is termoplastiese saamgestelde materiale veronderstel om meer impakweerstand te toon. Die toetse het ook getoon dat dik onversterkte termoplastieke veel hoër impakweerstand gehad het as die versterkte materiale. Vervaardigingseksperimente is uitgevoer om betroubare prosesseringsmetodes vir CFRTPs vas te stel. Daar is besef dat die hoër temperature wat vereis word om die materiale te prosesseer ook spesifieke prosesseringsverbruiksware en -gereedskap benodig. Die eksperimente het begin met die prosessering van reguit panele in ’n konveksie-oond met vakuumsaktegnieke. Daar is toe aanbeweeg na die outoklaafprosessering van onderdele met komplekse geometrie. Die rugleuning van ’n vliegtuigsitplek is gekies as die gevallestudie in die gebruik van CFRTPs. Hierdie toepassing vereis strukturele sterkte en styfheid en is ook onderhewig aan streng vereistes t.o.v. brand, rook, toksisiteit en hittevrystellimg (Engels FSTH). Die geometrie daarvan was kompleks genoeg om die gebruik van vermengde CFRTP-materiaal te demonstreer. Rugleunings is gemaak van beide CFRTPs en TSCs sodat ’n vergelyking tussen die twee tipes gemaak kon word. Die rugleuning is gemodelleer deur eindige element metodes (EEM) te gebruik om ’n aanvaarbare oplegging te bepaal. Hierdie oplegging is toe gebruik vir beide die CFRTP en TSC rugleunings om die gelykvormigheid tussen die rugleunings van beide materiale te verseker. LPET (Engels: modified polyethylene terephthalate) was die gekose termoplastiese matriks aangesien dit meer verkrygbaar was as PPS (Engels: polyphenylene sulphide) CFRTPs. Die rugleunings van beide materiale is vervaardig in ’n outoklaaf met ’n vakuumsakmetode en toe geintegreer deur die gebruik van kleefstowwe en setmate. Toetsing het getoon dat die styfheid en massa van die CFRTP rugleunings baie soortgelyk was aan die epoksie rugleunings. Dit impliseer dat vermengde CFRTP die plek van TSCs in soortgelyke gebruike kan inneem. ’n Basiese kostevergelyking is ook gedoen om die vervaardiging van CFRTP-rugleunings teenoor TSC-rugleunings te vergelyk.
8

Development of carbon fibre/polyamide 6,6 commingled hybrid yarn for textile-reinforced thermoplastic composites

Hasan, M. M. B., Staiger, E., Ashir, M., Cherif, C. 09 October 2019 (has links)
With increased use of carbon fibre (CF)-based textile-reinforced thermoplastic composites, the demand of hybrid yarns consisting of carbon filament yarns (CFYs) and thermoplastic filament yarns with improved properties is also high. Hybrid yarn manufacturing using commingling process by means of compressed air shows some distinct advantages over other hybrid yarn manufacturing processes. However, the potential of commingling process for the production of CF-based thermoplastic hybrid yarns is not yet fully explored. In this article, extensive investigations have been carried out for the development of commingled hybrid yarns manufactured from CFY and polyamide 6,6 (PA 6,6) filament yarns with improved adhesion properties between CFY and matrix in composites. Hybrid yarns are manufactured by varying air pressure and keeping overfeeds and delivery speed constant. Moreover, an additional heat treatment on CFY is done online for a better opening of CFY prior to the mixing with PA 6,6 filament yarn. The tensile properties of hybrid yarns as well as different mechanical properties of unidirectional composite, such as tensile, flexural, impact and interlaminar shear strength are investigated. The results show good potential for the development of hybrid yarns produced from CFY and thermoplastic filament yarns with improved adhesion properties for their application in textile-reinforced thermoplastic composites.
9

La pratique celtique des "têtes coupées" en France méditerranéenne : l’exemple du site du Cailar (Gard) au IIIe s. av. n. è. Approche archéothanatologique et traitements informatiques des données / Celtic severed head practice in southern France : The exemple of the Cailar’s settlement (Gard, France) during the IIIrd century BCE. Death archaeology approachand IT processing

Ciesielski, Elsa 20 December 2017 (has links)
En Gaule méridionale la pratique des têtes coupées, décrite par la littérature antique, est attestée par les vestiges lapidaires et les restes humains mis au jour depuis plus d’un siècle. Des données inédites sur cette coutume ont été acquises suite à la découverte au Cailar (Gard, France), à partir de 2003, d’un ensemble de crânes humains fragmentés, d’armement manipulé et de plusieurs dizaines de monnaies, dispersés dans les phases de remblaiement d’une place publique entre la fin du IVe et la fin du IIIe s av. n. è. Cette dernière appartient à une agglomération fortifiée fondée dès le VIe s. av. n. è. Les fragments de crânes trouvés sur ce site constituent le sujet de cette étude. Ces os forment un corpus assez différent des restes généralement associés aux têtes coupées : ils sont nombreux, très fragmentés et largement mélangés et dispersés dans les couches. Pour comprendre les évènements qui ont conduit à la création d’un tel assemblage, il a été nécessaire de mettre en place des outils adaptés à leur étude. Après une remise en contexte archéologique régionale et locale, ce travail se propose de présenter les méthodes de l’archéothanatologie adaptées à l’étude de ce type d’ossements (quantification, modification osseuses). Dans un deuxième temps, sont détaillés l’outil d’enregistrement créé pour optimiser l’étude (base de données/géodatabase, SIG), et les méthodes d’analyses spatiales retenues pour étudier non seulement les traces et les fractures des pièces osseuses, mais aussi leur répartition sur le terrain. Les résultats obtenus sont multiples : données quantitatives et taphonomiques précises sur l’assemblage, proposition d’une méthode inédite pour l’analyse de la découpe et de la fragmentation sur des crânes humains fragmentés, analyse poussée de la répartition spatiale dans les trois dimensions. Tous ces éléments permettent de proposer des hypothèses solides quant à la chaîne opératoire qui concerne les têtes coupées : mode de récupération, traitement, rejet, mise en place du dépôt. Ce travail permet également de suggérer des pistes à approfondir ou à abandonner dans les méthodes usuelles d’analyses des grands ensembles fragmentés et dispersés. / Once only known from Classical accounts, the practice of collecting and curating human heads by certain Iron Age groups in southern France has, for more than a century now, been evinced by materials including stone carvings and human remains. In particular, new evidence has been brought to light at the site of Le Cailar (Gard), a fortified site occupied from the end of the 6th century BCE. Specially, excavations carried out since 2003 have revealed an extensive deposit accumulated from the end of the 4th until the end of the 3rd century BCE, comprising fragmented human crania, purposefully deformed armaments, and many dozens of coins scattered across a public plaza, beneath a thick layer of rubble. The human cranial fragments discovered on this plaza are the subject of this study. These bones form a corpus quite different from the remains generally associated with severed heads: they are numerous, very fragmented, and largely mixed and dispersed in the levels. In order to understand the events that led to the creation of the assemblage, it has been necessary to adapt tools to this study. After putting the site into its local and regional context, this work proposes to present bioarchaeological methods adapted to the study of these types of bone (especially, quantification and modification of the bone). In a second time, the recording tool created to optimize the study is presented (database / geodatabase, GIS), then the spatial analysis methods used to study, not only the traces and the fractures of the parts bones, but also their distribution on the field. There are a lot of results: precise quantitative and taphonomic data about the assemblage, proposition of new method to study cut marks and fracturing, a hitherto unparalleled understanding of the process of how crania were distributed across the site (this last measured in three dimensions). All these elements permit to propose solid hypotheses regarding the process by which these heads were produced: the means of recuperation, treatment, disposal, and deposition. This work also suggests which avenues of research will or won't be useful to pursue in future projects of a similar nature.

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