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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.
331

C-Ply (Trademark) NCF Carbone extra fin : Etude du procédé de fabrication et optimisation du renfort / C-Ply (Trademark) Ultra light CarbonNCF : Study of the manufacturing process and textile reinforcement optimization

Singery, Vicky 03 February 2016 (has links)
L’industrie aéronautique travaille sur l’amélioration des systèmes propulsifs parl’introduction de composites dans la fabrication des aubes de soufflante afin d’alléger lastructure et ainsi de réduire la consommation en carburant des avions. Ces pièces réaliséesen tissage 3D présentent généralement des irrégularités de surface. Une manière d’optimisercet aspect est d’ajouter un pli additionnel de surface : nos travaux de thèse portent sur ledéveloppement de ce pli sous la forme d’un renfort « Non Crimp Fabric » (NCF) biaxial extrafinen fibre de carbone de module intermédiaire (IM), inférieur à 100 g/m², régulier et ayant unebonne déformabilité. Lors de nos travaux de thèse, nous avons utilisé la méthode des plans d’expériencepour améliorer la technologie d’étalement afin de répondre aux exigences demandées. Nousavons pu définir la configuration optimale d’étalement permettant d’atteindre la cible d’un pliinférieur à 50 g/m² en fibre de carbone IM. Pour réaliser un NCF extra-fin, après étalement,les plis sont assemblés par couture afin d’assurer la tenue du renfort. La combinaison decouture choisie (armure, tension, longueur, jauge …) conditionne l’aspect du NCF et sacapacité à être manipulée et déformée. Nous avons donc optimisé les paramètres de coutureafin d’obtenir les propriétés souhaitées. Après avoir optimisé l’étalement des fibres et l’assemblage des plis, nous avons réalisé et caractérisé les renforts NCF extra-fins pour valider leurs propriétés. Nous sommesfinalement parvenus à mettre au point un renfort NCF en fibre de carbone IM, inférieur à50 g/m² par pli ayant un taux de couverture supérieur à 98 % et une bonne capacité à sedéformer. / Aircraft manufacturers are working on the improvement of their engines bymanufacturing fan blades with advanced composite materials to reduce fuel consumption.However, fan blades are made from 3D woven fabrics which often have surface irregularities.It can be minimized by an additional thin layer on the surface : our thesis work is focused onthe development of a new textile structure based on ultra-thin biaxial “Non Crimp Fabric” (NCF)technology. This spread NCF made from intermediate modulus (IM) carbon fibers must belighter than 100 gsm, regular and deformable.During our thesis work, we used Design of Experiments (DOE) methodology to improvethe spreading technology used by Chomarat to make ultra-light NCF materials and meet theestablished requirements. We were able to reach the ultra-thin ply target of less than 50 gsmper ply. After optimizing the spreading process these thin ply tapes are stitched together tocreate NCF. Stability, visual aspect, handling and deformability are dependent on the stitchingsettings (stitching pattern, tension, length, gauge, etc.). Therefore we optimized the stitchingparameters to get the desired properties.After the spreading and stitching process had been optimized, the NCF weremanufactured and tested to validate the desired properties had been achieved. The testingconfirmed that we were able to develop a new carbon fiber NCF that was less than 50 gsm perply, had a coverage rate of higher than 98 % and had good deformability characteristics.
332

Contribution à la caractérisation du bruit de frottement des étoffes : application au prêt-à-porter (cas du vêtement furtif) / Contribution to the characterization the frictional noise of fabrics : application to ready-to-wear (case of furtive clothe)

Yosouf, Khaldon 18 March 2016 (has links)
Ce travail a pour objectif de caractériser et analyser le bruit de frottement des étoffes textiles généré lors de l’activité d’un individu (marche et course). Le présent travail apporte une contribution pour la caractérisation physique du bruit de frottement grâce à des paramètres physiques du son (bruit) et grâce à une nouvelle méthode de traitement du signal sonore des étoffes textiles, la transformée en S (transformée de Stokwell). L’évaluation sensorielle du bruit a été menée grâce à des panélistes entraînés en appliquant la méthode d’Analyse Descriptive Quantitative. Dans ce cadre, l’influence de l’armure d’étoffes en coton écru sur les propriétés sonores a été analysée. La corrélation entre les paramètres mécaniques des tissus qui décrivent l’état de surface et la compression de l’étoffe (mesurés par la chaîne de mesure Kawabata Evaluation System) et le niveau sonore global du bruit de frottement a été effectuée. Une corrélation entre le niveau sonore et les descripteurs sensoriels a été également menée. Le bruit d’une veste d’homme, confectionnée en deux types de prototypes présentant des variantes de manches, a été analysé en situation réelle, dans une chambre anéchoïque.Selon le traitement des signaux sonores, l’armure sergé 3 est la plus bruyante avec un niveau sonore, une amplitude du maximum les plus importants, pour les deux vitesse de frottement (marche et course), et une fréquence de maximum se trouvant dans la zone fréquentielle pour laquelle l’oreille humaine est la plus sensible. L’armure satin 4 est la plus ‘furtive’ avec un niveau sonore, une amplitude du maximum la moins importante et une fréquence correspondant importante et moins perceptible. Les résultats obtenus par l'analyse sensorielle sont cohérents avec les résultats obtenus en terme instrumental. Les panélistes qui participent à l'évaluation du bruit de frottement des étoffes textile ont perçu le bruit du satin 4 comme le bruit le plus sourd et le plus homogène, alors que le bruit du sergé 3 a été perçu comme le bruit le plus énergique et le plus disharmonique. Les modèles établis expriment que le niveau sonore augmente en fonction de la rugosité de surface et diminue en fonction de la résilience et de l'énergie de compression. Ainsi, plus que le niveau sonore est important, plus que le bruit est perçu plus polyphonique et plus grattant. Les bruits générés par le frottement de la veste avec les deux types de manche sont similaires en termes instrumental et sensoriel. / This work aims to characterize and analyze the frictional noise of textile materials generated during the activity of a subject (walking and running). This work contributes to the physical characterization of frictional noise characterized by physical parameters of sound (noise) and thanks to a new method of treatment of the acoustic signal, Stokwell-transform. Sensory evaluation of frictional noise was conducted by trained panelists using the Quantitative Descriptive Analysis method. In this context, the influence of the weave patterns of raw cotton fabrics on sound properties was analyzed. Correlations between the mechanical parameters of the fabric which describe the surface and the compressional proprieties of fabrics (measured by the Kawabata Evaluation System) and the sound level of the frictional noise were conducted. Correlations between the noise level and sensory descriptors were also conducted. The sounds of a man's jacket, fabricated in two types of prototypes with sleeves variants were analyzed in situation case, in an anechoic room. According to the treatment of acoustic signal, the twill 3 weave pattern is the noisiest one with a most important level sound and highest amplitude for the two types of movement (walking and running). The satin 4 weave pattern, which is the less noisy, presents a sound level and its highest amplitude is the less important. The frequency of highest amplitude is less important for twill 3 than satin 4. The results obtained by sensory analysis are coherent with the results obtained by instrumental characterization. The subjects participating to sensory evaluation of frictional noise of these fabrics perceived that the noise of satin 4 as the most muffled and most homogeneous noise, while the noise of twill 3 was perceived as the most dynamic and the most disharmonic one. Proposed models express that the sound level increases with the surface roughness and decreases with the resilience and the compression energy. The more sound level is important, the more the noise is perceived as polyphonic and scratching. The noise generated by the friction of the jacket with the two types of sleeves is similar whatever the evaluation.
333

Fabriquer la ville avec les lotissements : une qualification possible de la production ordinaire des espaces urbains contemporains ? / Build the city with residential allotments : What quality for ordinary urban spaces production?

Herrmann, Lou 03 May 2017 (has links)
Cette thèse analyse les modalités contemporaines de production des lotissements résidentiels en France ainsi que la qualité morphologique des espaces urbains produits dans ce cadre opérationnel. Elle interroge le paradoxe entre la critique presque unanime dont font l’objet les lotissements d’une part et l’observation d’opérations de lotissement exemplaires d’autre part. Elle explore les conditions selon lesquelles ce mode opératoire est en capacité de fabriquer des espaces urbains de qualité au niveau de leur forme physique. Les lotissements sont appréhendés selon une double entrée : en tant qu’espaces matériels, c’est la qualité de leur tissu qui est étudiée ; en tant que processus d’action, c’est le fonctionnement des systèmes d’action collective qui les composent qui est analysé. D’un point de vue théorique, le travail mobilise les outils de la sociologie des organisations en croisant les apports de l’analyse stratégique avec ceux de l’économie des ordres de grandeur. L’appréhension de la matérialité des lotissements s’appuie sur l’approche par trames développée autour de la notion de tissu urbain par l’école française de morphologie urbaine. La thèse repose sur l’analyse qualitative et comparative de quatre opérations-études de cas situées dans l’agglomération lyonnaise. Elle montre tout d’abord qu’il n’y a pas de fatalité morphologique. L’analyse du tissu des quatre lotissements prouve ainsi que ce mode opératoire n’est pas condamné à fabriquer des espaces urbains médiocres. Cette démonstration est issue d’un travail préalable de conceptualisation de la notion de qualité morphologique, envisagée comme une convention sociale. L’analyse de l’évolution du droit de lotir, dans le cadre plus global des changements réglementaires en matière d’urbanisme et d’aménagement en France, montre ensuite que l’injonction réglementaire au développement urbain durable impacte au moins indirectement le lotissement dans le sens de sa qualification. Les changements législatifs récents ont en effet conduit à l’instauration d’un contexte d’action qui pousse les maîtres d’ouvrage à une plus grande réflexion en termes de localisation des opérations, et sans doute aussi à une plus grande densité bâtie. Seulement le droit n’explique pas tout. Les arbitrages en matière de morphologie s’opèrent ainsi à trois moments clés : lors de la définition du droit des sols, au moment de la délivrance des autorisations d’urbanisme et lors de la conception et de la programmation des opérations. L’analyse révèle alors que l’acteur communal possède potentiellement une grande force de régulation de la forme urbaine. La planification locale a ainsi un impact significatif sur le tissu des opérations, même si l’expérience montre que c’est le plus souvent dans un sens négatif. Dans l’interaction avec les acteurs privés, que ce soient les lotisseurs et leurs concepteurs ou les habitants-maîtres d’ouvrage et leur constructeur, la commune dispose de multiples ressources pour influencer les projets dans le sens de leur qualification. La thèse montre à ce propos le rôle central des institutions partenaires dans ce rapport de pouvoir, notamment pour les plus petites communes. À ces différents moments, l’aptitude qualifiante de la régulation publique dépend d’une variable essentielle : l’engagement politique des acteurs. La qualité des lotissements est enfin conditionnée par un deuxième élément : la responsabilité morphologique dont se sentent ou non investis les lotisseurs. Ces derniers conservent en effet une certaine marge de manœuvre en matière morphologique. Leur comportement en termes de conception est donc lui aussi déterminant pour la qualité du tissu des lotissements. / This thesis analyses the contemporary modalities of the production of residential allotments (lotissements) in France, as well as the morphological quality of urban spaces produced in this operational framework. It questions the paradox between the almost unanimous criticism directed at these residential developments, on the one hand, and the observation of exemplary developmentoperations on the other hand. It explores the conditions under which this modus operandi can produce urban spaces with morphological qualities. The residential allotments are considered from a dual perspective: as a material space, by studying the quality of the urban fabric; and as a process, by analysing the functioning of the collective action systems composing it.From a theoretical perspective, this work makes use organisational sociology tools (sociologie des organisations) by crossing of the Strategic Analysis inputs (Crozier and Friedberg) with those of the Economies of Worth (Boltanski and Thévenot). The understanding of the development’s materiality draws on the “frames” approach (approche par trames) developed around the notion of urban fabric by the French school of urban morphology. The thesis relies on qualitative and comparative analysis of four case studies located in urban agglomeration of Lyon.Firstly, it shows that there is no morphological fatality. The fabric analysis of these four projects proves that this modus operandi is not doomed to produce mediocre urban spaces. This demonstration draws on a prior conceptualisation of the notion of morphological quality, considered as a social convention.The analysis of subdivision laws (droit de lotir), in the broader context of regulatory changes in the field of urbanism and town planning in France, then shows that the impact of sustainable development regulations is, at least indirectly, to increase the quality of the residential allotment. Legal changes have indeed created a context that encourages a stronger reflection on development location by the project manager (maître d’ouvrage) and probably also a greater building density.Nevertheless, laws cannot provide a full explanation. The decisions regarding morphology are made at three key moments: when the planning laws (droit des sols) are defined, when the planning approvals (autorisations d’urbanisme) are delivered and when developments are designed and programmed. The analysis so reveals that the municipal stakeholder potentially holds an important power over the regulation of the urban form. Local planning therefore has a significant impact on the developments’ fabric, although experience shows that this impact is most often negative. In the interaction with private stakeholders, whether they are the developers (lotisseurs) and their designers (concepteurs), or the inhabitants-project managers (habitants-maître d’ouvrage) and their builder (constructeurs), the municipality has many resources at his disposal to influence the projects quality. In this respect, this thesis highlights the central role that partner institutions play in this power relation, particularly for smaller municipalities. At these different moments, the aptitude of public regulation for improving quality depends on one essential variable: the political commitment of the stakeholders. Finally, the quality of the residential allotments also depends on a further element; whether or not the developers have a sense of morphological responsibility. Developers indeed maintain a room for manoeuver regarding morphology. Their behaviour at the conception level is consequently also decisive for the quality of the developments’ fabric.
334

an architecture of daily life: the continuing evolution of Toronto's residential fabric

Vermeulen, Stephanie January 2006 (has links)
This thesis envisions a new way of living in the city of Toronto. It is a vision that evolves not from the ideologies on which Toronto was founded, set out over 100 years ago when all multi-family dwellings were called tenements and tenements were considered, among other things, immoral. Instead, it is a vision founded on a city that has seen immense change over the last century, and faces an even greater rate of change over the next. Our city prides itself on its cultural and social diversity, yet, architecturally, we still struggle to adapt within a fabric of single-family homes. The Dutch provide an edifying example of an architecture of daily life, embodied by their attitude toward issues of privacy, toward traffic, toward work and play. Based on a case study of housing in the Netherlands, a country that has successfully and creatively adapted to the demands of housing in a climate of rapid immigration and a diversifying population, this thesis proposes new, high density urban housing typologies for the city of Toronto. This new vision for the city serves not only to add the necessary density to our existing neighbourhoods, but to foster a strong community life and to provoke new ideas about urban living.
335

Multiscale Modeling of Amphibian Neurulation

Chen, Xiaoguang 18 October 2007 (has links)
This thesis presents a whole-embryo finite element model of neurulation -- the first of its kind. An advanced, multiscale finite element approach is used to capture the mechanical interactions that occur across cellular, tissue and whole-embryo scales. Cell-based simulations are used to construct a system of constitutive equations for embryonic tissue fabric evolution under different scenarios including bulk deformation, cell annealing, mitosis, and Lamellipodia effect. Experimental data are used to determine the parameters in these equations. Techniques for obtaining images of live embryos, serial sections of fixed embryo fabric parameters, and material properties of embryonic tissues are used. Also a spatial-temporal correlation system is introduced to organize and correlate the data and to construct the finite element model. Biological experiments have been conducted to verify the validity of this constitutive model. A full functional finite element analysis package has been written and is used to conduct computational simulations. A simplified contact algorithm is introduced to address the element permeability issue. Computational simulations of different cases have been conducted to investigate possible causes of neural tube defects. Defect cases including neural plate defect, non-neural epidermis defect, apical constriction defect, and convergent extension defect are compared with the case of normal embryonic development. Corresponding biological experiments are included to support these defect cases. A case with biomechanical feedbacks on non-neural epidermis is also discussed in detail with biological experiments and computational simulations. Its comparison with the normal case indicates that the introduction of biomechanical feedbacks can yield more realistic simulation results.
336

Soft Materials under Air Blast Loading and Their Effect on Primary Blast Injury

Thom, Christopher January 2009 (has links)
Injury from blast is significant in both military and civilian environments. Although injuries from blast are well-documented, the mechanisms of injury are not well understood. Developing better protection requires knowledge of injury mechanisms and material response to blast loading. The importance of understanding how soft materials such as foams and fabrics behave under blast loading is further apparent when one realizes the capacity for some of these materials, frequently used in protective ensembles, to increase the potential for injury under some conditions. The ability for material configurations to amplify blast pressure and injury has been shown experimentally by other researches, and numerically in this study. Initially, 1-D finite element and mathematical models were developed to investigate a variety of soft materials commonly utilized in ballistic and blast protection. Foams, which have excellent characteristics in terms of energy absorption and density, can be used in conjunction with other materials to drastically reduce the amplitude of the transmitted pressure wave and corresponding injury. Additionally, a more fundamental examination of single layers of fabric was undertaken to investigate to the effects of parameters such as fabric porosity and density. Shock tube models were developed and validated against experimental results from the literature. After the models were validated, individual fabric properties were varied independently to isolate the influence of parameters in ways not possible experimentally. Fabric permeability was found to have the greatest influence on pressure amplification. Kevlar, a ballistic fabric, was modelled due to its frequent use for fragmentation protection (either stand-alone or in conjunction with a hard ballistic plate). The developed fabric and foam material models were then utilized in conjunction with a detailed torso model for the estimation of lung injury resulting from air blast. It was found that the torso model predicted both amplification and attenuation of injury, and all materials investigated as a part of the study had the capacity for both blast amplification and attenuation. The benefit of the models developed is that they allow for the evaluation of specific protection concepts.
337

Studie av smörjsystem / Study of lubrication systems

Axelsson, Erik, André, Samuel January 2011 (has links)
Målet med detta arbete är att undersöka smörjsystemet på två utsatta leder på en Boomer E2C. Förfrågan om examensarbetet kommer från Atlas Copco Rock Drills AB i Örebro som också tillverkar maskinen. Atlas Copco Rock Drills AB har idag ett fettsmörjningssystem som upprätthåller funktionerna på lederna. Uppgiften är att sammanfatta och utvärdera dagens system samt att finna nya lösningsförslag som skulle kunna ersätta eller delvis ersätta systemet. Information har hämtats från dokumentation, ritningar och samtal med konstruktörer på företaget. Efter att alla förutsättningarna för lederna specificerats så har lösningsförslag sökts. Genom att träffa lagerleverantörer och söka artiklar så har idéer formats. Brainstorming har använts för att kunna se nya lösningar. Undersökningen har visat att det finns problem med dagens lösning vad gäller slanghaverier och driftstopp i fält. Atlas Copco AB uttrycker även att kunskapen och dokumentationen angående systemet är otillräckligt. Efter artikelsökning så kan konstateras att forskningen och kunskapen på området med tungt belastade, oscillerande och fettsmörjda leder är liten. Dimensionering sker ofta med hjälp av erfarenhet och med tankesättet ”det har fungerat förut”. När lösningsförslagen har jämförts så har detta gjorts genom att använda metoden AHP (Analytic Hierachy Process). Med denna metod så jämför man kriterierna från kravspecifikationen med lösningsförslag så att man matematiskt kan räkna fram ett vinnande lösningsförslag. Resultatet visar att en smörjfri lösning skulle teoretiskt vara att föredra. Denna skulle tillverkas av en modern polymer och kompletteras med en inre tätning och ett yttre skydd. Atlas Copco rekommenderas att testa de olika förslagen för att komma fram till vilken som är bäst lämpad för applikationen. / The goal of this work is to investigate the lubrication system on two exposed joints on a Boomer E2C. The request for the thesis comes from Atlas Copco Rock Drills AB, Örebro, which also manufactures the machine. Today Atlas Copco Rock Drills AB has a grease lubrication system that secures the function of the joints. The task is to summarize and evaluate the current systems and to find new solutions that would be able to replace or partially replace the current system. Information was gathered from documents, construction drawings and conversations with engineers at the company. Solutions and ideas have been formed by meeting stock suppliers and searching for articles. Brainstorming has been used in order to find new solutions. The investigation has shown that there are problems with the current solution in terms of hose failures and downtime in the field. Atlas Copco AB also expresses that there is a lack of documentation and knowledge regarding the lubrication system. After the various article searches it became clear that research and knowledge in the area with heavy duty, oscillating and grease lubricated joints is insufficient. The design is often done with the help of experience and with the mindset "it has worked before." When the solutions and ideas have been compared, this has been done by using AHP (Analytic Hierarchy Process). This method compares the criteria that must be fulfilled by the solutions and then calculates the best one. The results show that a lubrication-free solution would theoretically be preferable. This would be produced by a modern polymer and supplemented with an inner seal and an outer protection. Atlas Copco is recommended to test the various proposals to be able to decide which the best solution for the application is.
338

an architecture of daily life: the continuing evolution of Toronto's residential fabric

Vermeulen, Stephanie January 2006 (has links)
This thesis envisions a new way of living in the city of Toronto. It is a vision that evolves not from the ideologies on which Toronto was founded, set out over 100 years ago when all multi-family dwellings were called tenements and tenements were considered, among other things, immoral. Instead, it is a vision founded on a city that has seen immense change over the last century, and faces an even greater rate of change over the next. Our city prides itself on its cultural and social diversity, yet, architecturally, we still struggle to adapt within a fabric of single-family homes. The Dutch provide an edifying example of an architecture of daily life, embodied by their attitude toward issues of privacy, toward traffic, toward work and play. Based on a case study of housing in the Netherlands, a country that has successfully and creatively adapted to the demands of housing in a climate of rapid immigration and a diversifying population, this thesis proposes new, high density urban housing typologies for the city of Toronto. This new vision for the city serves not only to add the necessary density to our existing neighbourhoods, but to foster a strong community life and to provoke new ideas about urban living.
339

Multiscale Modeling of Amphibian Neurulation

Chen, Xiaoguang 18 October 2007 (has links)
This thesis presents a whole-embryo finite element model of neurulation -- the first of its kind. An advanced, multiscale finite element approach is used to capture the mechanical interactions that occur across cellular, tissue and whole-embryo scales. Cell-based simulations are used to construct a system of constitutive equations for embryonic tissue fabric evolution under different scenarios including bulk deformation, cell annealing, mitosis, and Lamellipodia effect. Experimental data are used to determine the parameters in these equations. Techniques for obtaining images of live embryos, serial sections of fixed embryo fabric parameters, and material properties of embryonic tissues are used. Also a spatial-temporal correlation system is introduced to organize and correlate the data and to construct the finite element model. Biological experiments have been conducted to verify the validity of this constitutive model. A full functional finite element analysis package has been written and is used to conduct computational simulations. A simplified contact algorithm is introduced to address the element permeability issue. Computational simulations of different cases have been conducted to investigate possible causes of neural tube defects. Defect cases including neural plate defect, non-neural epidermis defect, apical constriction defect, and convergent extension defect are compared with the case of normal embryonic development. Corresponding biological experiments are included to support these defect cases. A case with biomechanical feedbacks on non-neural epidermis is also discussed in detail with biological experiments and computational simulations. Its comparison with the normal case indicates that the introduction of biomechanical feedbacks can yield more realistic simulation results.
340

Soft Materials under Air Blast Loading and Their Effect on Primary Blast Injury

Thom, Christopher January 2009 (has links)
Injury from blast is significant in both military and civilian environments. Although injuries from blast are well-documented, the mechanisms of injury are not well understood. Developing better protection requires knowledge of injury mechanisms and material response to blast loading. The importance of understanding how soft materials such as foams and fabrics behave under blast loading is further apparent when one realizes the capacity for some of these materials, frequently used in protective ensembles, to increase the potential for injury under some conditions. The ability for material configurations to amplify blast pressure and injury has been shown experimentally by other researches, and numerically in this study. Initially, 1-D finite element and mathematical models were developed to investigate a variety of soft materials commonly utilized in ballistic and blast protection. Foams, which have excellent characteristics in terms of energy absorption and density, can be used in conjunction with other materials to drastically reduce the amplitude of the transmitted pressure wave and corresponding injury. Additionally, a more fundamental examination of single layers of fabric was undertaken to investigate to the effects of parameters such as fabric porosity and density. Shock tube models were developed and validated against experimental results from the literature. After the models were validated, individual fabric properties were varied independently to isolate the influence of parameters in ways not possible experimentally. Fabric permeability was found to have the greatest influence on pressure amplification. Kevlar, a ballistic fabric, was modelled due to its frequent use for fragmentation protection (either stand-alone or in conjunction with a hard ballistic plate). The developed fabric and foam material models were then utilized in conjunction with a detailed torso model for the estimation of lung injury resulting from air blast. It was found that the torso model predicted both amplification and attenuation of injury, and all materials investigated as a part of the study had the capacity for both blast amplification and attenuation. The benefit of the models developed is that they allow for the evaluation of specific protection concepts.

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