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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.
501

Nanofibre optic force transducers with sub-piconewton resolution via near-field plasmon–dielectric interactions

Huang, Qian, Lee, Joon, Arce, Fernando Teran, Yoon, Ilsun, Angsantikul, Pavimol, Liu, Justin, Shi, Yuesong, Villanueva, Josh, Thamphiwatana, Soracha, Ma, Xuanyi, Zhang, Liangfang, Chen, Shaochen, Lal, Ratnesh, Sirbuly, Donald J. 15 May 2017 (has links)
Ultrasensitive nanomechanical instruments, including the atomic force microscope (AFM)(1-4) and optical and magnetic tweezers(5-8), have helped shed new light on the complex mechanical environments of biological processes. However, it is difficult to scale down the size of these instruments due to their feedback mechanisms9, which, if overcome, would enable high-density nanomechanical probing inside materials. A variety of molecular force probes including mechanophores(10), quantum dots(11), fluorescent pairs(12,13) and molecular rotors(14-16) have been designed to measure intracellular stresses; however, fluorescence-based techniques can have short operating times due to photo-instability and it is still challenging to quantify the forces with high spatial and mechanical resolution. Here, we develop a compact nanofibre optic force transducer (NOFT) that utilizes strong near-field plasmon-dielectric interactions to measure local forces with a sensitivity of <200 fN. The NOFT system is tested by monitoring bacterial motion and heart-cell beating as well as detecting infrasound power in solution.
502

Martin Luther, Home-Boy, Looks Outward*

Karant-Nunn, Susan C. 26 January 2017 (has links)
No description available.
503

Étude de la réponse biomécanique du thorax soumis à des sollicitations dynamiques dans un contexte civil et militaire par la méthode des éléments finis / Contribution to the development and the improvement of a digital model of the human body biofidelic HUByx by numerical methods for impact applications

Bodo, Michèle 06 November 2017 (has links)
L’étude des seuils de tolérance du corps humain aux impacts requiert des expérimentations sur des sujets humains vivants ou post-mortem, ce qui soulève naturellement des questions d’éthique. Pour pallier à ces limitations, le développement des outils numériques a conduit, au fil des dernières années à la mise en place des mannequins numériques plus ou moins capables de reproduire fidèlement le comportement mécanique du corps humain lorsqu’ils sont soumis à divers types de sollicitations. C’est dans ce contexte que le modèle de mannequin numérique HUByx (Hermaphrodite Biomechanics yx-model) a été développé au sein du département de recherche COMM du laboratoire ICB à l’UTBM. Ce travail de thèse a pour but la validation et l’amélioration de la biofidélité de la partie thoracique du modèle HUByx, et vise à comprendre les mécanismes de lésions et à rechercher des critères de prédiction des lésions thoraciques à travers la reconstruction numérique des chargements violents dans des contextes civils et militaires. Des simulations numériques ont été réalisées dans le cadres des études de chutes libres de personnes, des impacts balistiques non-pénétrants de projectiles non létaux et dans le cadre du phénomène de l’explosion. De bonnes corrélations ont été obtenues entre les résultats numériques et expérimentaux, contribuant ainsi à renforcer la capacité du modèle HUByx à répondre de manière biofidèle aux différentes sollicitations auxquelles il est soumis. Mots-clés : Biomécanique d’impacts, éléments finis, blessures thoraciques, critère visqueux, reconstruction d’accident, chutes libres, balistique, explosion. / The study of human tolerance thresholds to impacts requires experiments on living or post mortem human subjects, which naturally raises ethical questions. To overcome these limitations, the development of numerical tools has led over the last few years to the implementation of numerical models more or less capable to accurately reproduce the mechanical behavior of the human body when subjected to various types of stresses. It is in this context that the numerical model HUByx (Hermaphrodite Biomechanics yx-model) has been developed within the research department COMM of the ICB lab at UTBM. This PhD work aims at validating and improving the biofidelity of the thoracic part of the HUByx model and also aims to understand the mechanisms of lesions and to seek criteria for the thoracic injury prediction through the numerical reconstruction of violent loadings in civil and military contexts. Numerical simulations were carried out in the framework of human free falls studies, non-penetrating ballistic impacts of non-lethal projectiles and finally in the context of explosion phenomenon. Good correlations were obtained between the numerical and experimental results, thus contributing to reinforce the capacity of the HUByx model to respond in a biofidelic manner to the different stresses to which it is subjected. Keywords : Impact biomechanics, finite elements, thoracic injuries, viscous criterion, accident reconstruction, free falls, ballistics, explosion.
504

A script for a videotape to impart vision to church visitors and new church members

Springsted, Steven F. January 1988 (has links)
Thesis (M. Div.)--International School of Theology, 1988. / Abstract. "A ministry tool ..." Includes bibliographical references (leaves [69]-78).
505

A modified Park's stitch to correct aortic insufficiency for bioprosthetic valve at time of left ventricular assist device implant: a case report

Kazui, Toshinobu, Sydow, Nicole, Friedman, Mark, Kim, Samuel, Lick, Scott, Khalpey, Zain 30 November 2016 (has links)
Background: Aortic valve insufficiency (AI) at the time of left ventricular assist device (LVAD) insertion needs to be corrected, however there is little known about how to manage bioprosthetic valvular AI. Case presentation: A 55-year-old female with dilated cardiomyopathy who previously had a bioprosthetic aortic valve replacement needed a LVAD as a bridge to transplant. Her left ventricular ejection fraction was 10% and had mild to moderate transvalvular AI. She underwent a HeartWare HVAD insertion along with aortic valvular coaptation stitch repair (Park's stitch) to the bioprosthetic valve. Conclusion: Her AI improved to trivial with minimal ejection through the bioprosthetic valve. She was transplanted 6 months following the surgery. A Park's stitch to the bioprosthetic aortic valve with more than mild AI might be a good option for bridge to transplant patient.
506

Analyse comparative des relations entre les communautés latinos de Miami, Los Angeles and Boston / Comparative analysis of the intra communautary relationships among Latinis in Boston, Los Angeles and Miami

Mallet, Marie-laure 17 September 2013 (has links)
Cette thèse traite de la cohésion des groupes latinos dans la société américaine. Elle analyse l’influence des relations intra-communautaires sur l’insertion des Latinos dans la société américaine et déconstruit la représentation des communautés latinos perçues comme monolithiques afin de déterminer dans quelle mesure ces relations conduisent à des assimilations différenciées. Elle montre notamment que l’insertion dans la société américaine découle des relations entre différentes communautés latinos et analyse l’influence du contexte de réception sur cette insertion socio-économique, sur les pratiques politiques et, de façon plus générale, le poids politique de ces groupes.Le choix de métropoles aussi diverses que Miami, Los Angeles et Boston souligne l’importance du contexte urbain sur la formation des relations entre ces différents groupes latinos, et son influence sur leur insertion dans la société américaine, mesurée par les stratégies adoptées par les groupes latinos et par leur participation politique. Cette analyse est cruciale pour comprendre la complexité des interactions entre groupes dont les relations représentent un enjeu de taille, car elles permettent d’anticiper l’avenir des relations ethniques aux Etats-Unis. Cette perspective ouvre ainsi sur un contexte sociologique plus large, permettant d’anticiper les problèmes politiques et économiques auxquels les Etats-Unis seront confrontés en matière d'intégration, d’immigration et de représentation dans les décennies à venir. / This dissertation examines the cohesion of Latino groups in American society. It analyses the influence of intra-community relations on the integration of Latinos in American society and deconstructs the representation of Latino communities perceived as a monolithic group allowing to determine to what extent these relationships lead to different assimilation paths. In particular, it shows the differential impact of the relationships between different Latino communities on their integration into American society and investigates the influence of the context of reception on the socio-economic integration of different Latino groups, policies and practices, and, more generally, their political clout.The choice of cities as diverse as Miami, Los Angeles and Boston highlights the importance of the urban context on the formation of relationships between the different Latino groups, and its influence on their integration into American society, as measured by the group strategies that Latinos adopt and their political participation.This analysis is crucial to the understanding of the complex interactions between Latino groups whose relationships are a major challenge, as they allow to anticipate the future of ethnic relations in the United States. This perspective opens to a broader sociological context which may help better comprehend the political and economic issues that the United States will confront in topics such as integration, immigration and representation in the coming decades.
507

Liber daticus Roskildensis Roskilde gavebog og Domkapitlets anniversarieliste,

Otto, Alfred, January 1933 (has links)
A. Otto's Thesis--Copenhagen.
508

Design of Intelligent Internet of Things and Internet of Bodies Sensor Nodes

Shitij Tushar Avlani (11037774) 23 July 2021 (has links)
<div>Energy-efficient communication has remained the primary bottleneck in achieving fully energy-autonomous IoT nodes. Several scenarios including In-Sensor-Analytics (ISA), Collaborative Intelligence (CI) and Context-Aware-Switching (CAS) of the cluster-head during CI have been explored to trade-off the energies required for communication and computation in a wireless sensor network deployed in a mesh for multi-sensor measurement. A real-time co-optimization algorithm was developed for minimizing the energy consumption in the network for maximizing the overall battery lifetime of individual nodes.</div><div><br></div><div>The difficulty of achieving the design goals of lifetime, information accuracy, transmission distance, and cost, using traditional battery powered devices has driven significant research in energy-harvested wireless sensor nodes. This challenge is further amplified by the inherent power intensive nature of long-range communication when sensor networks are required to span vast areas such as agricultural fields and remote terrain. Solar power is a common energy source is wireless sensor nodes, however, it is not reliable due to fluctuations in power stemming from the changing seasons and weather conditions. This paper tackles these issues by presenting a perpetually-powered, energy-harvesting sensor node which utilizes a minimally sized solar cell and is capable of long range communication by dynamically co-optimizing energy consumption and information transfer, termed as Energy-Information Dynamic Co-Optimization (EICO). This energy-information intelligence is achieved by adaptive duty cycling of information transfer based on the total amount of energy available from the harvester and charge storage element to optimize the energy consumption of the sensor node, while employing event driven communication to minimize loss of information. We show results of continuous monitoring across 1Km without replacing the battery and maintaining an information accuracy of at least 95%.</div><div><br></div><div>Decades of continuous scaling in semiconductor technology has resulted in a drastic reduction in the cost and size of unit computing. This has enabled the design and development of small form factor wearable devices which communicate with each other to form a network around the body, commonly known as the Wireless Body Area Network (WBAN). These devices have found significant application for medical purposes such as reading surface bio-potential signals for monitoring, diagnosis, and therapy. One such device for the management of oropharyngeal swallowing disorders is described in this thesis. Radio wave transmission over air is the commonly used method of communication among these devices, but in recent years Human Body Communication has shown great promise to replace wireless communication for information exchange in a WBAN. However, there are very few studies in literature, that systematically study the channel loss of capacitive HBC for <i>wearable devices</i> over a wide frequency range with different terminations at the receiver, partly due to the need for <i>miniaturized wearable devices</i> for an accurate study. This thesis also measures and explores the channel loss of capacitive HBC from 100KHz to 1GHz for both high-impedance and 50Ohm terminations using wearable, battery powered devices; which is mandatory for accurate measurement of the HBC channel-loss, due to ground coupling effects. The measured results provide a consistent wearable, wide-frequency HBC channel loss data and could serve as a backbone for the emerging field of HBC by aiding in the selection of an appropriate operation frequency and termination.</div><div><br></div><div>Lastly, the power and security benefits of human body communication is demonstrated by extending it to animals (animal body communication). A sub-inch^3, custom-designed sensor node is built using off the shelf components which is capable of sensing and transmitting biopotential signals, through the body of the rat at significantly lower powers compared to traditional wireless transmissions. In-vivo experimental analysis proves that ABC successfully transmits acquired electrocardiogram (EKG) signals through the body with correlation accuracy >99% when compared to traditional wireless communication modalities, with a 50x reduction in power consumption.</div>
509

OPTIMIZATIONS FOR N-BODY PROBLEMS ON HETEROGENOUS SYSTEMS

Jianqiao Liu (6636020) 14 May 2019 (has links)
<div><div>N-body problems, such as simulating the motion of stars in a galaxy and evaluating the spatial statistics through n-point correlation function, are popularly solved. The naive approaches to n-body problems are typically O(n^2) algorithms. Tree codes take advantages of the fact that a group of bodies can be skipped or approximated as a union if their distance is far away from one body’s sight. It reduces the complexity from O(n^2) to O(n*lgn). However, tree codes rely on pointer chasing and have massive branch instructions. These are highly irregular and thus prevent tree codes from being easily parallelized. </div><div><br></div><div>GPU offers the promise of massive, power-efficient parallelism. However, exploiting this parallelism requires the code to be carefully structured to deal with the limitations of the SIMT execution model. This dissertation focusses on optimizations for n-body problems on the heterogeneous system. A general inspector-executor based framework is proposed to automatically schedule GPU threads to achieve high performance. Essentially, the framework lets the GPU execute partial of the tree codes and profile threads behaviors, then it assigns the CPU to re-organize these threads to minimize the divergence before executing the remaining portion of the traversals on the GPU. We apply this framework to six tree traversal algorithms, achieving significant speedups over optimized GPU code that does not perform application-specific scheduling. Further, we show that in many cases, our hybrid approach is able to deliver better performance even than GPU code that uses hand tuned, application-specific scheduling. </div><div> </div><div>For large scale input, ChaNGa is the best-of-breed n-body platform. It uses an asymp-totically-efficient tree traversal strategy known as a dual-tree walk to quickly provide an accurate simulation result. On GPUs, ChaNGa uses a hybrid strategy where the CPU performs the tree walk to determine which bodies interact while the GPU performs the force computation. In this dissertation, we show that a highly optimized single-tree walk approach is able to achieve better GPU performance by significantly accelerating the tree walk and reducing CPU/GPU communication. Our experiments show that this new design can achieve a 8.25x speedup over baseline ChaNGa using one node, one process per node configuration. We also point out that ChaNGa's implementation doesn't satisfy the inclusion condition so that GPU-centric remote tree walk doesn't perform well.</div></div>
510

L'efficacité des modes de communication d'un changement organisationnel selon divers paramètres culturels

Rakotomalala, Olivier Tantelinirina January 2010 (has links)
La communication est un élément incontournable dans les organisations lors des périodes de changement, qui sont elles-mêmes inhérentes à toute organisation. Il existe une variété de modes de communication d'un changement lors de son implantation. L'objectif de cette recherche consiste à explorer les liens entre des modes de communication et des caractéristiques culturelles des destinataires d'un changement. Cent-vingt et un étudiants d'origines culturelles diverses et habitant les résidences d'une université québécoise ont servi d'échantillon pour l'étude d'un changement devant y être implanté. Les variables culturelles suivantes ont été mesurées chez ces participants : l'individualisme vertical, l'individualisme horizontal, le collectivisme vertical et le collectivisme horizontal. Trois modes de communication matérialisés en trois vignettes annonçant un changement (le mode monologique, le mode dialogique, et le mode séducteur) ont été utilisés auprès de trois groupes distincts de participants dont les préoccupations face au changement ainsi annoncé ont ensuite été mesurées. Des analyses de régressions multiples n'ont pas permis de confirmer les hypothèses, à savoir que les niveaux de l'ensemble des préoccupations seraient plus bas lors d'une communication monologique pour les personnes ayant un haut niveau d'individualisme vertical, lors d'une communication dialogique pour celles qui ont un haut niveau d'individualisme horizontal ainsi que lors d'une communication dite séductrice pour celles qui ont un haut niveau de collectivisme vertical. Par contre, des analyses exploratoires ont montré qu'un haut niveau d'individualisme horizontal pourrait conduire à avoir davantage de préoccupations liées à la résistance au changement lors d'une communication dialogique. Dans le même sens, de hauts niveaux de collectivisme vertical ou d'individualisme vertical amèneraient l'expression d'un plus grand nombre de préoccupations liées au soutien au changement lors de communications monologiques ou séductrices. Ces données amènent à supposer que les préoccupations, voire la résistance au changement, seraient maximisées par une communication adéquate et qu'elles seraient favorables au changement. Les modes de communication adéquats et les réactions des destinataires d'un changement ne seraient pas les mêmes dans toutes les cultures.

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