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MicromobileRunkvist, Adils January 2015 (has links)
I have designed and built a small home for myself that is movable by a bicycle. The structure is thought to fit in different places such as in a park, on a street or in the nature. I have been living in the structure for a short period of time, trying it out in different places around Stockholm. I want to understand the consequences of living minimal, to get the whole experience from an idea to the final result. What are the the ingredients of a home today beyond the absolute need of protection? / Jag har ritat och byggt en mobil strucktur som är flyttbar med en cykel. Jag har bott i strukturen en period runt om i Stockholm, för att testa hur självständigt det går att bo och på vilka platser det går att bo. Projektet handlar också om hemmet idag, hur kan det fungera och se ut?
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Monitoring Bone Micro-architecture with a Special Focus on Bone Strength2015 August 1900 (has links)
Introduction. Osteoporosis is a chronic disease characterized by the loss of bone mass and the deterioration of bone micro-architecture leading to a subsequent increase in fracture risk. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides non-invasive measures of bone micro-architecture and strength in live humans but its ability to monitor small skeletal changes is yet poorly understood. The objectives of this thesis were to 1) determine HR-pQCT precision for volumetric density, geometry, cortical and trabecular micro-architecture, as well as estimates of bone strength; 2) determine the monitoring time interval (MTI) and least significant change (LSC) metrics; and 3) to characterize annual changes in bone area, density, and micro-architecture at the distal radius and tibia using HR-pQCT in postmenopausal women.
Methods. To determine precision error as well as monitoring and change metrics of the distal radius and tibia, 34 postmenopausal women (mean age 74, SD±7 years) from the Saskatoon cohort of the Canadian Multicentre Osteoporosis Study (CaMos) were measured using HR-pQCT. To characterize the annual change in bone outcomes of this same cohort, 51 women (mean age±SD: 77±7 years) were measuring at baseline and again 1 year later. Precision errors were calculated as coefficient of variation (CV% and CV%RMS). The LSC was determined from precision errors and then divided by the median annual percent changes to define MTIs for bone area, density, and micro-architecture. Repeated measures analysis of variance (ANOVA) with Bonferroni adjustment for multiple comparisons were used to characterize the mean annual change in total density, cortical perimeter, trabecular and cortical bone area, density, content, and micro-architecture. Significant changes were accepted at P<0.05.
Results and Discussion. HR-pQCT precision errors were <10% for bone densitometric, geometric, and mechanical properties; while precision errors were <16% for cortical and trabecular micro-architectural outcomes. Further, the use of either automatic or modified contour methods for the dual-threshold technique for cortical micro-architectural analysis provided similar precision. Densitometric and geometric outcomes had longer monitoring times (>3 years), while micro-architecture had monitoring times of ~2 years. The observed annual changes were statistically significant for several outcomes; however, only cortical and trabecular area, as well as cortical density at the distal tibia changed beyond the LSC. Overall, thesis findings will assist design and interpretation of prospective HR-pQCT studies in postmenopausal women.
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Texture Analysis of Diffraction Enhanced Synchrotron Images of Trabecular Bone at the Wrist2013 August 1900 (has links)
The purpose of this study is to determine the correlation between texture features of Di raction
Enhanced Imaging (DEI) images and trabecular properties of human wrist bone in the assessment
of osteoporosis. Osteoporosis is a metabolic bone disorder that is characterized by reduced bone
mass and a deterioration of bone structure which results in an increased fracture risk. Since the
disease is preventable, diagnostic techniques are of major importance. Bone micro-architecture and
Bone mineral density (BMD) are two main factors related to osteoporotic fractures. Trabecular
properties like bone volume (BV), trabecular number (Tb.N), trabecular thickness (Tb.Th), bone
surface (BS), and other properties of bone, characterizes the bone architecture. Currently, however,
BMD is the only measurement carried out to assess osteoporosis. Researchers suggest that bone
micro-architecture and texture analysis of bone images along with BMD can provide more accuracy
in the assessment.
We have applied texture analysis on DEI images and extracted texture features. In our study,
we used fractal analysis, gray level co-occurrence matrix (GLCM), texture feature coding method
(TFCM), and local binary patterns (LBP) as texture analysis methods to extract texture features.
3D Micro-CT trabecular properties were extracted using SkyScanTM CTAN software. Then, we
determined the correlation between texture features and trabecular properties. GLCM energy fea-
ture of DEI images explained more than 39% of variance in bone surface by volume ratio (BS/BV),
38% of variance in percent bone volume (BV/TV), and 37% of variance in trabecular number
(Tb.N). TFCM homogeneity feature of DEI images explained more than 42% of variance in bone
surface (BS) parameter. LBP operator - LBP 11 of DEI images explained more than 34% of vari-
ance in bone surface (BS) and 30% of variance in bone surface density (BS/TV). Fractal dimension
parameter of DEI images explained more than 47% of variance in bone surface (BS) and 32% of
variance in bone volume (BV). This study will facilitate in the quanti cation of osteoporosis beyond
conventional BMD.
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Reclaiming the Napali CoastMunz, Lucas B. 10 October 2017 (has links)
No description available.
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Squelettisation en un balayage. Application à la caractérisation osseuse.Arlicot, Aurore 24 October 2012 (has links) (PDF)
La squelettisation est une méthode de reconnaissance et de caractérisation des formes utilisant des notions de topologie discrète, qui permet d'extraire le squelette d'une forme binaire. Ce squelette (un sous ensemble de la forme centré, fin, topologiquement équivalent à la forme et reconstructible) se calcule grâce à plusieurs balayages de l'image. Dans ce travail de thèse nous nous sommes intéressé au calcul du squelette en une seule passe (mode " streaming "). Pour cela nous avons proposé un nouvel algorithme qui ré-ordonne les calculs sur chaque pixels dans leur ordre d'apparition dans l'image (sans changer le sens de propagation de l'information dans l'image) en calculant une carte de distance asymétrique puis qui trouve les points de l'axe médian. Selon un ordre particulier, qui garantit l'identité de nos résultats avec ceux d'un algorithme de référence, nous pouvons supprimer les points de la carte de distance en ne conservant que les points du squelette dont les points de l'axe médian. En plus du fait que nos squelettes soient identiques au pixel près à ceux obtenus par l'algorithme de référence, notre algorithme les calcule plus rapidement. Bien que notre approche soit générique, nous avons utilisé cet algorithme pour développer un outil logiciel en imagerie médicale permettant d'extraire les caractéristiques osseuses dans le but de mesurer la structure osseuse à partir du squelette obtenu sur des images de micro-scanner. L'extraction de zones d'os trabéculaire 2D sur des images binarisées, permet bien une caractérisation de l'os en accord avec la vérité terrain obtenue par d'autres logiciels.
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Multifaceted Architecture and the Public spaceLarsson, Douglas January 2020 (has links)
Focusing on human interaction with the dense built environment in a city, this essay exploresthe experienced space, i.e. the physical built space and the perceived space as one dimension.From this perspective, the essay considers the visual information that the built environmentprojects. The essay proposes a theorem for understanding and categorizing architecture basedon its potential diversity of activities that the building encapsulates. The ability to interpretand challenge the perceived understanding of the built environment supplies the basis for thekey concept of this essay: multi-faceted architecture.In this essay, multi-faceted architecture is a motto for architectural design and planning, andderives from the fact that the very meaning of a function for a given piece of architecture issomething that needs to be addressed further by the architect, designer or other buildingexperts. As our modern cities expand at an ever-increasingly higher speed, the need for publicspace with a multi-faceted architecture is needed more than before. Firstly, the essay definesthe concept of multi-faceted architecture and its constituents. Secondly, the essay supplies aframework for analysing Multifaceted architecture and a way of categorizing it. This essayaims at opening a deeper dialogue on architectural quality based upon theory from currentarchitectural theorists and architectural theory. The essay uses a sociological perspective tounderstand why appropriate architecture, in the context of the surrounding environment, canlead to a more successful activation of a given space. To test the theorem that concernsmulti-faceted architecture, the theorem is applied and tested in the old city of Malmö. Due tothe COVID-19 virus outbreak, these tests have been executed virtually. Thirdly, this essayreflects upon the role of multi-faceted architecture in a modern city.
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Interventions nutritionnelles, exercice physique et perturbations métaboliques : réponses micro-architecturales, densitométrique, biomécaniques et cellulaires du tissu osseux chez le rat mâle. Induction de l'obésité et prise en charge.Gerbaix, Maude 11 June 2012 (has links)
Si l’obésité a longtemps été considérée comme protectrice pour le squelette, sa prise en charge nutritionnelle s’accompagne d’une perte osseuse. Dans le but d’étudier les mécanismes liant le tissu adipeux et le tissu osseux, des rats ont été nourris avec un régime riche en graisse et en sucre afin d’induire une obésité et ses complications métaboliques. Puis, ces rats ont suivi un programme de prise en charge de l’obésité associant un rééquilibrage nutritionnel à de l’activité physique. Des investigations de la densité, de la micro architecture trabéculaire, de la qualité corticale, des propriétés biomécaniques et des paramètres cellulaires du tissu osseux ont été réalisées sur le squelette des rats. L’obésité induite a amélioré les paramètres densitométriques et corticaux des rats. La prise en charge de l’obésité a entraîné des effets contrastés. Le rééquilibrage de l’alimentation n’a pas altéré la densité ni les paramètres biomécaniques et corticaux du tissu osseux des rats en dépit d’altérations de la micro architecture et des perturbations l’activité cellulaire osseuse. L’exercice a augmenté la densité minérale osseuse du tibia des rats. Nos résultats montrent que l’inclusion de l’exercice dans un programme de prise en charge de l’obésité permet de potentialiser la perte de masse grasse et de maintenir l’intégrité du squelette. En étudiant l’impact d’un régime obésogène et de la prise en charge de l’obésité sur le tissu osseux chez le rat, ce travail de thèse apporte sa contribution dans la compréhension des mécanismes liant le tissu adipeux et le tissu osseux. / While obesity has long been considered protective of bone tissue, its nutritional management is linked to a concomitant bone loss. In order to access these mechanisms, male rats were given a high fat / high sucrose diet to induce obesity and its resulting metabolic disorders. Then, these rats participated in a well balanced nutritional program combined, or not, with physical activity in order to treat their obesity. Investigations on density, trabecular micro-architecture, cortical quality, biomechanical properties and cellular parameters of bone tissue were performed on rat’s skeleton. Obesity had improved the bone density and cortical parameters of rats. Obesity management had induced mixed effects. The well balanced diet did alter neither the bone density nor biomechanical and cortical parameters despite the presence of alterations in the trabecular micro architecture and some disturbances of bone cellular activity. Exercise by itself had increased the tibia bone mineral density. Our results show that including exercise in obesity management allows increasing the fat mass loss and maintaining the skeleton integrity. By studying the impact of an obesogenic diet and obesity treatment on bone tissue in rats, this study brings its contribution to the understanding of the mechanisms linking adipose tissue and bone tissue.
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Contribution à l'arithmétique des ordinateurs et applications aux systèmes embarqués / Contributions to computer arithmetic and applications to embedded systemsBrunie, Nicolas 16 May 2014 (has links)
Au cours des dernières décennies les systèmes embarqués ont dû faire face à des demandes applicatives de plus en plus variées et de plus en plus contraintes. Ce constat s'est traduit pour l’arithmétique par le besoin de toujours plus de performances et d'efficacité énergétique. Ce travail se propose d'étudier des solutions allant du matériel au logiciel, ainsi que les diverses interactions qui existent entre ces domaines, pour améliorer le support arithmétique dans les systèmes embarqués. Certains résultats ont été intégrés au processeur MPPA développé par Kalray. La première partie est consacrée au support de l'arithmétique virgule flottante dans le MPPA. Elle commence par la mise au point d'une unité flottante matérielle basée sur l'opérateur classique FMA (fused multiply-Add). Les améliorations proposées, implémentées et évaluées incluent un FMA à précision mixte, l'addition à 3 opérandes et le produit scalaire 2D, à chaque fois avec un seul arrondi et le support des sous-Normaux. Cette partie se poursuit par l'étude de l'implémentation des autres primitives flottantes normalisées : division et racine carrée. L'unité flottante matérielle précédente est réutilisée et modifiée pour optimiser ces primitives à moindre coût. Cette première partie s’ouvre sur le développement d'un générateur de code destiné à l'implémentation de bibliothèques mathématiques optimisées pour différents contextes (architecture, précision, latence, débit). La seconde partie consiste en la présentation d'une nouvelle architecture de coprocesseur reconfigurable. Cet opérateur matériel peut être dynamiquement modifié pour s'adapter à la volée à des besoins applicatifs variés. Il vise à fournir des performances se rapprochant d'une implémentation matérielle dédiée sans renier la flexibilité inhérente au logiciel. Il a été spécifiquement pensé pour être intégré avec un cœur embarqué faible consommation du MPPA. Cette partie s'attache aussi à décrire le développement d'un environnement logiciel pour cibler ce coprocesseur ainsi qu'explorer divers choix architecturaux envisagés. La dernière partie étudie un problème plus large : l'utilisation efficace de ressources arithmétiques parallèles. Elle présente une amélioration des architectures régulières Single Instruction Multiple Data tels qu’on les trouve dans les accélérateurs graphiques (GPU) pour l'exécution de graphes de flot de contrôle divergents. / In the last decades embedded systems have been challenged with more and more application variety, each time more constrained. This implies an ever growing need for performances and energy efficiency in arithmetic units. This work studies solutions ranging from hardware to software to improve arithmetic support in embedded systems. Some of these solutions were integrated in Kalray's MPPA processor. The first part of this work focuses on floating-Point arithmetic support in the MPPA. It starts with the design of a floating-Point unit (FPU) based on the classical FMA (Fused Multiply-Add) operator. The improvements we suggest, implement and evaluate include a mixed precision FMA, a 3-Operand add and a 2D scalar product, each time with a single rounding and support for subnormal numbers. It then considers the implementation of division and square root. The FPU is reused and modified to optimize the software implementations of those primitives at a lower cost. Finally, this first part opens up on the development of a code generator designed for the implementation of highly optimized mathematical libraries in different contexts (architecture, accuracy, latency, throughput). The second part studies a reconfigurable coprocessor, a hardware operator that could be dynamically modified to adapt on the fly to various applicative needs. It intends to provide performance close to ASIC implementation, with some of the flexibility of software. One of the addressed challenges is the integration of such a reconfigurable coprocessor into the low power embedded cluster of the MPPA. Another is the development of a software framework targeting the coprocessor and allowing design space exploration. The last part of this work leaves micro-Architecture considerations to study the efficient use of parallel arithmetic resources. It presents an improvement of regular architectures (Single Instruction Multiple Data), like those found in graphic processing units (GPU), for the execution of divergent control flow graphs.
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Grow Pods: Flexible Design to Regenerate Urban LandscapesRoberts, Rachel K 01 January 2012 (has links) (PDF)
Shifts in economics, demographics, and lifestyle in America have lead to changes in this country's urban landscape. Rural and urban populations have migrated toward the suburbs and concentrated metro areas, leaving holes in the urban fabric of small and midsized cities. Often these empty spaces become drivers of blight, crime, and discouragement in the community.
The goal of the Grow Pods Project is to transform the negative of vacant urban lots into an opportunity for improving health, building community, and encouraging positive growth.
As a tool for integrating the food system directly into the urban context, this project addresses the need for innovative solutions to the complex issues of city land use. Grow Pods aim to help communities redirect a trajectory of decline toward a future that is focused on the health and wellbeing of the urban environment and the people who live in it. Transformation and transportability are intrinsic features of the design, in acknowledgement of the necessity for any component of a contemporary city in flux to be dynamic enough to reinvent itself within its evolving context.
The Grow Pod project is focused on the South End Neighborhood of Springfield, MA, a city whose population and industrial base has decreased since much of its infrastructure was designed. Located in the fertile Connecticut River Valley, it is also in a region with a rich agricultural history.
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Caractérisation de la gonarthrose sur radiographie X par analyse de la texture de l’os trabéculaire / Characterization of radiographic knee osteoarthritis using trabecular bone textureJanvier, Thomas 02 December 2016 (has links)
Cette thèse présente l’apport d’une analyse fractale de la texture de l’os trabéculaire sur des clichés de radiographie du genou pour la caractérisation de la gonarthrose. Dans un premier temps cette analyse de texture a été confrontée aux méthodes actuelles de suivi de la pathologie afin de valider leur intérêt dans le suivi clinique des patients. Un second temps a été consacré à la prédiction de l’initiation de la pathologie où aucun marqueur ne fait référence. L’analyse de texture a été menée en utilisant des approches fractales permettant de s’affranchir des problèmes de variation d’acquisition entre différents centres cliniques tout en comparant différentes méthodes de calcul. La texture osseuse trabéculaire a été analysée à différentes plages d’échelle afin de caractériser les mécanismes sous-jacents de modification de la microarchitecture osseuse induits par la gonarthrose. Nous avons pu mettre en évidence l’intérêt prédictif de cette analyse peu coûteuse et largement accessible dans le cadre aussi bien de l’initiation que de la progression de l’arthrose du genou. / This thesis presents the contribution of the trabecluar bone texture fractal analysis on knee radiographs for the knee osteoarthritis characterization. Firstly, this texture analysis was confronted to the actual methods of the pathology clinical monitoring in order to validate their interest in the patients monitoring. Secondly, the prediction of the knee osteoarthritis initiation was investigated, domain in which there are still no markers defined. The texture analysis was performed using fractal approaches avoiding the problems of the variations in the acquisition among different clinical centers and comparing different computing methods. Trabecular bone texture was analyzed at different ranges of scale in order to characterize the underlying mechanisms of the microarchitecture modification induced by the knee osteoarthritis. Thus, we highligthed the predictive interest of this cheap and largely available analysis for both the initiation and the progression of the knee osteoarthritis.
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