Wireless sensor networks (WSNs) groups specialized transducers that provide sensing services to Internet of Things (IoT) devices with limited energy and storage resources. Since replacement or recharging of batteries in sensor nodes is almost impossible, power consumption becomes one of the crucial design issues in WSN. Clustering algorithm plays an important role in power conservation for the energy constrained network. Choosing a cluster head (CH) can appropriately balance the load in the network thereby reducing energy consumption and enhancing lifetime. This paper focuses on an efficient CH election scheme that rotates the CH position among the nodes with higher energy level as compared to other. The algorithm considers initial energy, residual energy, and an optimum value of CHs to elect the next group of CHs for the network that suits for IoT applications, such as environmental monitoring, smart cities, and systems. Simulation analysis shows the modified version performs better than the low energy adaptive clustering hierarchy protocol by enhancing the throughput by 60%, lifetime by 66%, and residual energy by 64%.

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Verificando a importância da morfologia dos arcos dentários no tratamento ortodôntico, a proposta deste estudo foi avaliar e comparar as formas e dimensões de arcos de 30 indivíduos com oclusão normal e 30 com má-oclusão de Classe IIdivisão 1ª, geradas a partir de três categorias de pontos de referência. Foram demarcados nos modelos de estudo: os pontos médios das faces vestibulares dos dentes (1ª categoria de pontos); pontos no rebordo alveolar, perpendiculares aos anteriores e sobre a junção muco-gengival (2ª categoria de pontos); e pontos mesiais e distais das superfícies oclusais dos dentes. Todos os pontos foram digitalizados e convertidos automaticamente para o sistema de coordenadas x, y e z pela máquina de medidas tridimensional da Mitutoyo (modelo Crysta-Apex/C). Um software, especialmente desenvolvido para este trabalho, criou um conjunto de pontos de referência virtuais (3ª categoria de pontos) a partir dos pontos mesiais e distais das superfícies oclusais previamente demarcados nos modelos, que representou o fundo dos canais de encaixe de braquetes. Além disso, gerou curvaturas por meio de equações matemáticas (parábola, elipse, catenária e função beta) que se ajustaram, pelo método dos mínimos quadrados, às 3 diferentes categorias de pontos de referência, e mediu as dimensões transversais dentárias e dos rebordos alveolares. A seleção da equação matemática que melhor descreveu cada categoria de pontos de referência foi realizada por meio de avaliação do menor valor do erro médio. A curvatura do rebordo selecionada foi deslocada sobre o eixo y até tangenciar o ponto médio virtual do incisivo central mais anterior, simulando a inserção de um arco ortodôntico, e foram medidas as distâncias entre esta curvatura e os pontos médios virtuais dos outros dentes. Todos os dados foram organizados em tabelas de acordo com a categoria dos pontos de referência, os arcos (superior ou inferior) e o tipo de oclusão. Verificou-se que todas as dimensões transversais dentárias e dos rebordos superiores, e posteriores inferiores são estatisticamente maiores nos indivíduos com oclusão normal do que nos indivíduos com má-oclusão de Classe II; e que as distâncias transversais dos rebordos alveolares são estatisticamente maiores do que as dentárias. Quanto às formas dos arcos, a catenária, seguida da elipse, foram as que melhor descreveram as suas curvaturas, independentemente da categoria de pontos e do tipo de oclusão. As outras formas, como a parábola e a gerada pela função beta, foram observadas com baixo percentual de ocorrência. As formas dos arcos não caracterizaram diferencialmente os tipos de oclusão e as 3 categorias de pontos de referência estudadas. Praticamente todos os pontos médios virtuais apresentaram-se internamente posicionados em relação à curvatura do rebordo alveolar quando esta foi deslocada até o ponto médio virtual do incisivo central mais vestibularizado, sendo encontrados valores estatisticamente maiores no arco superior dos indivíduos com má-oclusão de Classe II-divisão 1ª. Este dado revela maior tendência a vestibularização dos dentes superiores nestes indivíduos, quando o rebordo alveolar é utilizado como guia para a construção do arco ortodôntico, embora as diferenças entre os grupos não nos pareçam clinicamente importantes. / Given the importance of dental arch morphology in orthodontic treatment, we have evaluated and compared, based on three categories of reference points, the shapes and dimensions of the arches of 30 subjects with normal occlusion and 30 subjects with Class II, division 1 malocclusions. .The points marked on the study casts were: the middle points of the buccal surfaces of teeth (first category of points); points on the alveolar ridge, perpendicular to those of the first category and on the mucogingival junction (second category of points); and mesial and distal points of the occlusal surfaces of the teeth. All points were digitized and automatically converted to the x, y and z system of coordinates by a three-dimensional measurement machine (Mitutoyo - Crysta-Apex/C model). A computer software program especially developed for our study created a set of virtual reference points (third category of points) based on the distal and mesial points on the occlusal surfaces previously marked on the casts, which represented the most inner point of the bracket slot. In addition, the software generated curvatures using mathematical equations that were adjusted to the three categories of reference points by the method of minimum squares, and measured the transversal dimensions of teeth and alveolar ridges. Selection of the mathematical equation that best described each category of reference points was performed by evaluating the smallest value for the mean error. The selected ridge curvature was shifted on the y-axis until it became tangential to the virtual middle point of the most anterior central incisor, simulating the insertion of an orthodontic arch, and the distances between this curvature and the virtual middle point on the other teeth were measured. All data were tabulated according to reference point category, arch (upper or lower), and type of occlusion. We observed that all transversal dimensions of teeth, upper ridges and lower posterior ridges were statistically greater in subjects with normal occlusion than in subjects with Class II malocclusions; and that the transversal distances of the alveolar ridges were statistically greater than those of the teeth. As to arch shape, the catenary, followed by the ellipse, were the shapes that best described the arch curvatures, regardless of reference point category and occlusion type. The other shapes, such as the parabola and the shape generated by the Beta function, were observed at lower frequencies. The arch shapes did not differentially characterize the several types of occlusion or the 3 reference point categories studied. Practically all virtual middle points were located internally to the curvature of the alveolar ridge when this curvature was shifted up to the virtual middle point of the most buccaly projected central incisor, and the subjects with Class II division 1 malocclusion were found to have statistically greater values for the upper arch. This observation reveals a greater trend for buccally projected upper teeth in these subjects when the alveolar ridge is used as a guide to construct the orthodontic arch, although the differences observed between the groups do not seem to be clinically important.

Extensos corpos d’água como reservatórios hidrelétricos, aqui estudados, podem ser fontes consideráveis de gases de efeito estufa ('CH IND.4' e 'CO IND.2') devido à decomposição de parte da biomassa da floresta submersa e também pela biomassa alóctone e autóctone. Este trabalho apresenta concentrações e estimativas de fluxos difusivos e ebulitivos desses gases dissolvidos na coluna d’água, nos reservatórios hidrelétricos de Miranda (MG), Xingó (AL/SE), Ribeirão das Lages (RJ) e Represa do Lobo (SP) durante o período de outubro de 2001 a agosto de 2003. Utilizou-se, em perfis verticais, um sensor 'CH IND.4' de estado sólido comercial provido de detector de metano semicondutor, cuja superfície, ao adsorver o gás, varia sua resistência interna fornecendo sinal relacionado à concentração de gás. Foram usadas câmaras de troca difusiva na determinação de fluxos de troca de 'CH IND.4' e 'CO IND.2' na interface água-atmosfera e funis de captura de bolhas para processos ebulitivos. Mediram-se algumas variáveis físicas e químicas. Os perfis de gás metano dissolvido em água apresentaram elevadas concentrações, geralmente com valores crescentes desde próximo a superfície até a interface água-sedimento. Porém, sumidouros oxidativos presentes na coluna d’água, que consomem o gás metano no seu percurso até a superfície, juntamente com convecções impelidas pelo vento, foram responsáveis por perfis de diferentes tipos com concentrações alternadas, em conseqüência dessa ação. Fluxos difusivos também foram calculados a partir de experimentos de troca difusiva de gases dissolvidos na interface água-atmosfera resultando em emissões de 'CH IND.4' e 'CO IND.2' para atmosfera, e em alguns casos, absorção de 'CO IND.2' pelo reservatório / Extended water bodies such as the hydroelectric reservoirs here studied can be greenhouse gas sources ('CH IND.4' and 'CO IND.2') due to decay of part of submerged forest biomass and also due to allochtonous and autochtonous organic compounds. This work presents concentrations, ebullitive and diffusive fluxes of the gases dissolved in the water column in the following reservoirs : Miranda, Xingó, Ribeirão das Lages and Lobo, between October 2001 and August 2003. In the course of this work methane profiles were determined by a commercial methane sensor, a solid state device, the electrical resistance of which varies as a function of absorbed methane providing a signal related to dissolved gas concentration. Diffusion chambers were used to measure 'CH IND.4' and 'CO IND.2' exchange rates at the air-water interface; bubble capture funnels were used for ebullitive emission. Some physical and chemical variables were also measured. Dissolved methane profiles showed high concentrations, generally with increasing values from water surface to sediment. However, the oxidative methane sink in the water column consumes this gas in its upward migration path and together with wind-propelled convection produces different profile types. Diffusive flux was also calculated from diffusive exchange experiments of these gases at the air-water interface, which showed 'CH IND.4' and 'CO IND.2' emission, sometimes 'CO IND.2' absorption, by the reservoir

Depuis plusieurs années, le Groupe de Physico-Chimie Organique Spatiale au sein du LISA a développé un programme expérimental en laboratoire ayant pour objectif de simuler la chimie atmosphérique de Titan. Des techniques d'analyse ont été développées pour détecter et quantifier les composés formés au cours de ces simulations : spectrométrie d'absorption IR et Chromatographie en Phase Gazeuse Couplée à la Spectrométrie de Masse (CPG-SM) pour les composés gazeux, analyse élémentaire et pyrolyse couplée à la CPG-SM pour les composés solides déposés sur les parois du réacteur. Cependant, vu la complexité de la chimie étudiée, les mécanismes de formation des espèces dans le réacteur (et notamment des analogues d'aérosols de Titan) n'étaient toujours pas compris et la représentativité de l'énergie utilisée dans ce type d'expérience par plasma froid (électrons au lieu de photons UV) pour simuler les conditions stratosphériques de Titan sérieusement contestée. A l'aide d'un couplage entre l'expérience et un modèle cinétique du plasma froid, nous avons pour la première fois expliqué les mécanismes ayant lieu dans cette simulation expérimentale. Nous avons déterminé l'énergie déposée par les électrons dans la décharge; détecté, en plus des composés gazeux, les espèces à courte durée de vie (radicaux, ions, espèces excitées) in situ par spectrométrie d'émission UV-Vis; et comparé l'évolution de l'abondance relative des espèces avec les sorties du modèle. Le radical CH a été détecté dans nos simulations alors qu'il n'est pas pris en compte par la plupart des modèles photochimiques de l'atmosphère de Titan. Ainsi, s'il est présent dans l'atmosphère de Titan, il pourrait entraîner la formation de C2H2, dont l'abondance est actuellement sous-estimée d'environ 30% par les modèles photochimiques. Nous avons détecté l'ammoniac (NH3) parmi les produits majoritaires dans nos expériences. Sa présence possible sous forme condensée pourrait expliquer le comportement de l'albédo de Titan vers 5 µm avec une forte absorption des glaces d'ammoniac autour de 5,25 µm. Si sa présence se révélait confirmée par CIRS, le spectromètre IR embarqué à bord de la mission Cassini-Huygens, ce composé d'intérêt exobiologique interviendrait dans les processus de croissance des aérosols de Titan, et notamment pourrait réagir avec l'acide cyanhydrique (HCN) pour former NH4CN, qui peut produire, en présence d'eau, des bases puriques telles que l'adénine et la diaminopurine. Provenant des apports cométaires et météoritiques, la présence en quantité notable de composés oxygénés (CO, CO2 et H2O) dans l'atmosphère de Titan nous a conduit à mener la première simulation expérimentale contenant initialement N2/CH4/CO (98/1,99/0,01) afin de vérifier l'impact du monoxyde de carbone (CO), composé oxygéné majoritaire dans l'atmosphère de Titan, sur la composition de la phase gazeuse. Nous avons identifié par deux techniques d'analyse (spectrométrie IR et CPG-SM) l'oxyrane (ou oxyde d'éthylène, C2H4O) comme composé organique oxygéné majoritaire. Ce composé a été détecté dans le milieu interstellaire et sa possible présence sur Titan pourra être confirmée par CIRS (signature à 11,4 µm). L'évolution de l'abondance des espèces dans la décharge ainsi que celle de la composition atomique des tholins en fonction des paramètres expérimentaux a permis de proposer un processus de remplacement d'un hydrogène porté par un carbone par un radical C≠N ayant lieu sur les composés organiques gazeux. Cette hypothèse est en accord avec des réactions proposées par les modèles de chimique atmosphérique : HCN + CN  C2N2 + H k = 6,31.10-17 Tg1,57 exp (-50/Tg) cm3.s-1 C2H2 + CN  HC3N + H k = 5,67.10-9 Tg-0,55 exp(-4/Tg) cm3 s-1 C2H4 + CN  CH2CHCN + H k = 1,25.10-10 (Tg/300)0,7 exp(-30/Tg) cm3 s-1 Ce type de réactions serait aussi possible avec les polyynes pour former des cyanopolyynes : C4H2 + CN  HC5N + H k = 2.10-10 cm3 s-1 C6H2 + CN  HC7N + H k = 2.10-10 cm3 s-1 C8H2 + CN  HC9N + H k = 2.10-10 cm3 s-1 Concernant les tholins, le même type de mécanisme aurait lieu sur une structure constituée de systèmes conjugués. La comparaison entre l'énergie déposée dans le réacteur et celle arrivant dans l'atmosphère de Titan a pour la première fois été réalisée, permettant ainsi de discuter de la représentativité énergétique du plasma. La puissance fournie par les électrons dans le plasma est 108 fois plus importante que celle apportée par les photons dans les domaines d'énergie correspondant aux dissociations du méthane et de l'azote (> 10eV ; < 150 nm). Une comparaison avec les taux de production des composés solides a montré que la simulation expérimentale a un taux de production environ 104 fois inférieur à celui de Titan (taux rapporté à la puissance déposée).

This study focuses on the Internet auction in the market of jade from Ming or Ch¡¦ing dynasty. Yahoo/Kimo auction, which is the biggest net auction site in Taiwan, has been selected as the research site in the project. Jade from Ming or Ch¡¦ing dynasty is the major goods in this research because of its distinguishable characteristics and reasonable price in the market. ¡§Case studies¡¨ have been chosen as the methodology of this research. Interviews with six jade sellers, trading records of consumers, and observation from the researcher have become methods of data collection. This study attempts to discover workable strategists for jade sellers in the Internet auction. The main research questions are: (1)Why do sellers choose Yahoo/Kimo auction as the site to sell jade of Ming or Ch¡¦ing dynasty¡H(2)How do sellers manipulate perception of consumers to influence their decision making¡H(3)How does rating and feedback work in marketing jade¡H(4)How to pricing¡HHow to satisfy different marketing segmentation¡H Three conclusions have been summarized as following: In Taiwan, Yahoo/Kimo auction site is a suitable site for jade trading because the site is user friendly, with huge size of pictures showing the characteristics of jade, with fast searching engine, low running cost, and highly security system. If a seller wants to run a stylish store, he/she is suggested to design the website by himself/herself. Generally speaking, most consumers in Internet auction are lack of understanding of jade. Therefore, enriching the description and pictures of goods and lowering the price become key points to influence consumers¡¦ decision making. Another fact found in the study is that the rating and feedback system is useful for convincing consumers at the beginning time; however, it plays less and less important role especially for consumers to make their final decisions. Selling with low-price is unable to reach the exceptional profits, but is considered as a way to clean out stocks. High-price jade is hardly to market through Internet auction because it needs a real site to sell it. ¡§Under the table¡¨ bargaining is commonly seen in Internet auction. In the future, the researcher suggests jade sellers in Internet to specialize jade items, to demonstrate in a theme or a style when marketing.

The purpose of this dissertation is to examine the life of Wordsworth as presented in The Prelude through the approach of Ch¡¦an (Zen) Buddhism. Three other topics will be touched on in addition to an introduction to Ch¡¦an: language, I and nature. Basic notions of Ch¡¦an are introduced to form a basis for the understanding of and interpretation of later chapters. The language of Wordsworth is analyzed to show two key points: the empty essence of language and Wordsworth¡¦s attachment to abstractions. The emptiness of abstractions in this chapter also serves as a basis for the discussions of nature in chapter four. The notion of self in The Prelude is examined in the episodes of Wordsworth¡¦s life to see his attachments and detachments; joy and sadness. Nature is then analyzed and divided into ¡§nature as it is¡¨ and ¡§nature as is meant¡¨ through the examination of The Prelude. The research finds that Wordsworth¡¦s early exposure to nature helps cultivate a much selfless ¡§I,¡¨ which explains his devotion to the French Revolution as he pursues it for the welfare of the public. His experiences of oneness with nature helps him experience rare cases of beauty, sublimity, develop imagination, and are later used as a powerful momentum to fight the conflict and pain in life. Yet as his experiences of one with nature gradually fade away from his memories under the constant conflict of his later grown-up life, he is more and more sucked into the gyration of differentiation. The mistakening of empty abstractions for his life¡¦s ideal gets him into the web of transcendental signifiers without any real solace. Attaching to abstractions only makes him stay away from the real and trap in the world of distinction and illusion. Only when he is back in nature and reality can he regain his pleasantness and joy.

Le travail de thèse réalisé rentre dans le cadre de la lutte contre les émissions de gaz à effet de serre en trouvant des solutions de piégeage du CO₂ moins coûteuses en énergie que les procédés conventionnels (absorption aux amines et les procédés TSA/PSA). L'objectif est d'étudier les conditions thermodynamiques et cinétiques d'un procédé de captage de CO₂ par formation d'hydrates de gaz. Les hydrates de gaz présentent des propriétés de sélectivité et une capacité de stockage importantes pour une séparation de gaz.<br />L'étude des aspects thermodynamiques a consisté à la détermination des diagrammes de phase permettent de juger la faisabilité de la technique. Nous avons montré que les pressions opératoires peuvent être importantes dans le cas où la phase liquide est uniquement constituée d'eau. Pour limiter les coûts de compression, nous avons utilisé le TBAB (TetraButylAmmoniumBromide) comme additif. L'utilisation de cet additif permet de réduire considérablement les pressions opératoires avec un gain pouvant aller jusqu'à un facteur 16. Cependant ce gain de pression s'accompagne d'une perte de capacité de stockage. Nous avons également montré que le modèle de van der Waals et Platteeuw permet de décrire les diagrammes de phase obtenus. L'effet du TBAB sur la solubilité des gaz est également déterminé avec des comportements différents selon les gaz. <br />Pour la partie cinétique, nous avons montré expérimentalement une consommation préférentielle du CO₂ dans les premiers instants de la cristallisation. Un modèle cinétique reposant sur un couplage des bilans matière et bilans de population adapté pour les mélanges de gaz est proposé. Le modèle décrit parfaitement l'évolution de la consommation totale de gaz et le phénomène de consommation préférentielle du CO₂ au début de la cristallisation. Ce modèle avec les paramètres cinétiques adéquats permet de suivre la granulométrie qui est une caractéristique importante pour les aspects de transport des hydrates de gaz.

Made available in DSpace on 2015-02-24T18:20:50Z (GMT). No. of bitstreams: 1 RoseliaCO.pdf: 983581 bytes, checksum: ef2f8147e4e96309fcc1540df1994ca6 (MD5) Previous issue date: 2005-01-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Au cours de cette recherche, nous traitons la reinterpr?tation de cette campagne de P? no Ch?o Tamb?m se Aprende a Ler , tout en utilisant un moyen d?fini a travers les parlers de femmes qui avaient travaill? dans le projet d alphab?tisation d?velopp? par la Mairie de la Ville de Natal au d?but des ann?es 1960. Le parler de cinq femmes/ ?ducatrices, participantes actives de ce projet, se constitue en tant qu unit? principale de r?f?rence de ce travail. ? partir de leurs t?moignages nous avons cherch? ? contextualiser et enrichir un peu plus la p?riode concernante ? l av?nement de la Campagne. Il s agit de t?moignages qui ont des rapports avec l ?ducation, la culture et la conscientisation politique, v?hicule ? la compr?hension du contexte historique dans lequel s ins?rait le groupe engag? dans la Campagne de P? no ch?o tamb?m se aprende a ler .Nous avons d?velopp? notre travail ? travers la m?thodologie compr?hensible du discours (Kaufmann, 1996), tout en m?langeant le mat?riel recherch? et la th?orie. Les consid?rations finales font ?tat de nos impressions ? propos de ce projet ? partir des t?moignages de ces cinq femmes/?ducatrices. Le gouvernement de Djalma Maranh?o se caracterize pu democratie et populaire et ce travail ?ducatif consid?rer subversives a d?cennie 1960 / Ao longo desta pesquisa, tratamos da reinterpreta??o da Campanha de P? no Ch?o Tamb?m se Aprende a Ler. Para o alcance desse objetivo, utilizamos fragmentos de discursos pronunciados por cinco mulheres/educadoras, que atuaram no projeto de alfabetiza??o, desenvolvido pela Prefeitura de Natal no in?cio dos anos 1960. A unidade de refer?ncia principal desta pesquisa se constitui das falas desses cinco sujeitos participantes do referido projeto. Partindo de seus relatos, buscamos compreender a rede de rela??es que circunda a equipe da Prefeitura, e principalmente que configura e desvela os sentidos do projeto tal como ? percebido na atualidade por essas protagonistas. Procuramos perceber de que forma essas mulheres visualizavam sua pr?tica educativa e os motivos que as levaram a participar de um projeto considerado, na ?poca, como popular e democr?tico. Desenvolvemos este trabalho a partir da metodologia compreensiva do discurso (KAUFMANN,1996), entrela?ando a fala das mulheres entrevistadas com estas teorias. As considera??es finais revelam o quanto o preconceito, o medo e a viol?ncia rondaram a d?cada de 1960, fazendo-se presente no cotidiano local, particularmente atrav?s do olhar dessas cinco mulheres/educadoras. E como a gest?o do Prefeito Djalma Maranh?o era caracterizada como aberta, popular e subversiva e foi considerada como de grande amea?a ? ordem pol?tica e social do Estado.Seus olhares nos apontam ainda caminhos para que possamos ampliar o debate acerca da educa??o popular na d?cada de 1960