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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.
141

Evaluating the Ability of eQUEST Software to Simulate Low-energy Buildings in a Cold Climatic Region

Srivastava-Modi, Shalini 20 December 2011 (has links)
Building Simulation is widely used for understanding how a building consumes energy and for assessing design strategies aimed at improving building energy efficiency. The present research study uses eQUEST, a popular simulation software. Various simulations are done here to analyse and critically comment on the best design strategies to be used in order to vastly reduce the energy consumption of a recently constructed small (1800 m2 floor area) commercial building in Brampton, Ontario, which is a heating dominated region. The limitations faced with eQUEST while simulating the modified design are critiqued. A complete understanding of the building science and heat flow through the building envelope has been applied to modify the building in question. After all the changes applied, the overall heat load of the building was reduced to 15 kWh/m2/yr and the overall energy consumption reduced by 60 percent.
142

Evaluating the Ability of eQUEST Software to Simulate Low-energy Buildings in a Cold Climatic Region

Srivastava-Modi, Shalini 20 December 2011 (has links)
Building Simulation is widely used for understanding how a building consumes energy and for assessing design strategies aimed at improving building energy efficiency. The present research study uses eQUEST, a popular simulation software. Various simulations are done here to analyse and critically comment on the best design strategies to be used in order to vastly reduce the energy consumption of a recently constructed small (1800 m2 floor area) commercial building in Brampton, Ontario, which is a heating dominated region. The limitations faced with eQUEST while simulating the modified design are critiqued. A complete understanding of the building science and heat flow through the building envelope has been applied to modify the building in question. After all the changes applied, the overall heat load of the building was reduced to 15 kWh/m2/yr and the overall energy consumption reduced by 60 percent.
143

Efeitos de raios-X de baixa energia em células mamárias / Effects of low energy x-rays in mammary cells

Flávia Ventura dos Passos 12 August 2011 (has links)
Doses de radiação de baixa energia podem induzir quebras de dupla fita no DNA assim como também produzir perfis alterados de expressão de genes relacionados a estas lesões. Os danos não reparados ou mal reparados levam a uma maior suscetibilidade à transformação oncogênica já que os efeitos biológicos mais importantes causados pela radiação ionizante são mutação e carcinogênese. As lesões no DNA provocadas pela radiação podem também ocasionar o surgimento micronúcleos e as células podem ser induzidas à apoptose. O objetivo deste trabalho é estudar in vitro a presença de micronúcleos e a apoptose ocasionados por Raios-X de baixa energia. Pretende-se analisar estes efeitos biológicos em relação à energia equivalente à utilizada em exames mamográficos usando duas linhagens estabelecias de células de mama: a MCF-7 (tumoral) e a HB-2 (não-tumoral). As células, em crescimento exponencial, foram irradiadas no equipamento de arranjo experimental de mamografia do LCR/UERJ. A dose de 5Gy na energia de 30 kV foi aplicada com taxa de 0,1 Gy/seg utilizando filtro de 0,03 mm de molibdênio. As irradiações foram realizadas duas vezes, após as irradiações, as células foram incubadas por 4, 24 ou 48 horas e posteriormente coradas com o corante Hoechst33258 para análise em microscopia de fluorescência. Para cada análise, 1000 células foram categorizadas pela morfologia do núcleo. Os resultados mostraram que a HB-2, utilizada neste estudo como célula mamária normal, apresentou maior sensibilidade aos efeitos da radiação, com 37 % das células em apoptose após 4 hs de incubação, enquanto a MCF-7 apresentou 6,5 %. Nas análises após 24 hs foi possível confirmar a radioresistência da MCF-7 tendo sido observadas 11% de células em apoptose no grupo irradiado. Houve um aumento crescente de micronúcleos radioinduzidos nas duas linhagens de acordo com os tempos de incubação. Na análise de 4 hs a HB-2 apresentou 3%, em 24 hs, 8,5% e 48 hs, 11,5 %. Diante destes resultados, foi possível concluir que a energia do feixe de raios-X utilizada na mamografia pode ser capaz de ocasionar aumento de ocorrência de apoptose e geração de micronúcleos nas duas linhagens estudadas / Radiation doses of low-energy can induce double-stranded breaks in DNA as well resulting in altered profiles of gene expression related to these injuries. The damage is not repaired or poorly repaired leading to increased susceptibility to oncogenic transformation since most important biological effects caused by ionizing radiation are mutation and carcinogenesis. The DNA lesions caused by radiation can also provoke the presence of micronuclei and as result cells can be induced to apoptosis. The aim of this work is to perform a preliminary study "in vitro" to identify the presence of micronuclei caused by low energy. X-rays. It is intended analyze these biological effects caused by x-rays with energy equivalent to the ones used in mammography in two very well established breast: cell lines the MCF-7 (tumor) and HB-2 (non-tumor). Cells in exponential growth were irradiated using an experimental arrangement with a mammography tube of the LCR / UERJ. The dose of 5Gy was used for 30 kVp x-rays using 0.03 mm filter molybdenum with a fixed dose rate of 0.1 Gy / sec. The irradiations were repeated twice and. the cells were incubated for 4, 24 or 48 hours and stained with dye Hoechst 33258 for fluorescence microscopy analysis. For each analysis 1000 cells were categorized by the morphology of the nucleus. The results revealed that the HB-2, used in this study as normal mammary cell have showed high sensitivity to the effects of radiation, with 37% of cells undergoing apoptosis after incubation of 4hs, while MCF-7 showed 6.5%. In the 24 hour-analysis it was confirmed the radiation resistance of MCF-7 were it was observed 11% of cells in apoptosis in the irradiated group. There was an increasing number of radiation-induced micronuclei in both cell lines, according to the incubation times. After 4 hours, HB-2 presented 3% of micronuclei, in 24 hours, the experiment reveled 8.5%, and after 48 hours it increased to 11.5%. As result of this study we may conclude that the energy used in mammography is capable to cause an increase in incidence of apoptosis and in the production of micronuclei in both cell lines studied
144

Lithographie directe à faisceaux d’électrons multiples pour les nœuds technologiques sub-20nm / Multibeam lithography for sub20nm technological nodes

Jussot, Julien 28 September 2015 (has links)
Depuis de nombreuses années, l'industrie microélectronique s'est engagée dans une course à l'augmentation des performances et à la diminution des coûts de ses dispositifs grâce à la miniaturisation de ces derniers. La génération de ces structures de petites dimensions repose essentiellement sur l'étape de lithographie. Dans cette optique, plusieurs techniques de lithographie nouvelle génération (NGL) sont en cours de développement afin de pouvoir répondre aux besoins de l'industrie pour les nœuds technologiques inférieurs à 20 nm. Parmi elles, les solutions de lithographie à faisceaux d'électrons multiples semblent très prometteuses grâce à leur écriture directe sans masque (ML2), ainsi que leur coût et encombrement réduits. Le CEA-LETI s'est associé à l'entreprise Mapper Lithography basée aux Pays-Bas afin d'aider au développement d'une technologie de lithographie électronique à faisceaux d'électrons multiples basse énergie (d'énergie 5 keV). Les travaux de thèse de ce manuscrit visent à contribuer au développement de cette technologie qui pourrait à terme permettre de réaliser des dispositifs CMOS pour les nœuds technologiques actuels et futurs. L'intégration d'une nouvelle technique de lithographie dans l'industrie repose sur 3 grands critères du procédé lithographique, la production horaire (sensibilité), la résolution (taille minimale des structures réalisées) et la rugosité de ligne. La rugosité de ligne est devenue l'un des paramètres les plus critiques limitant à l'heure actuelle la miniaturisation et pour cause cette dernière impacte de manière négative les performances des dispositifs. Alors que l'ITRS préconise une rugosité de ligne inférieure à 1.7 nm pour les futurs nœuds technologiques inférieurs à 20 nm, les lithographies actuelles ne permettent pas d'obtenir des rugosités inférieures à 4-5 nm. Les travaux de cette thèse visent la minimisation de la rugosité de ligne de résine imprimée par lithographie électronique en proposant des stratégies alternatives d'écriture ou en modifiant les empilements de matériaux sous-jacents la résine, ou encore par l'introduction de traitements post-lithographiques tels que des recuits thermiques ou des traitements plasma. Les études ont montré qu'en combinant une stratégie d'écriture et un traitement plasma à base de dihydrogène une réduction de 41% du LWR pouvait être obtenue. / For decades, the growth of the Semiconductor Industry (SI) has been driven by the paramount need for faster devices at a controlled cost primarily due to the shrinkage of chip transistors. The performances of future CMOS technology generations still rely on the decrease of the device dimensions. However, the photolithography is, today, the limiting factor for pattern miniaturization and the technology has been at a standstill since the development of 193-nm water-based immersion lithography. Moreover, another parameter limiting further semiconductor scaling is the transistor gate linewidth roughness (LWR), i.e. the standard deviation of the gate critical dimension (CD) along the line. The LWR needs to be controlled at the nanometer range to ensure good electrical performances of the future CMOS device. The lithography step is again identified as the root cause of the gate LWR. Indeed, the significant LWR (4-5 nm) of the patterns printed by photolithography is transferred into the gate during the subsequent plasma etching steps, resulting in a final gate LWR far above the sub-2 nm LWR targeted for the sub-20 nm technological nodes. In order to continue scaling down feature sizes of devices, the semiconductor industry is waiting for the maturity of next generation lithographies (NGL). Among NGL, one can find the promising mask-less direct-write techniques (ML2) in which multiple electron beam lithography (multibeam lithography) is regarded as a serious candidate for providing high resolution structures at a low cost. The firm MAPPER Lithography, associated with CEA-LETI is working on the development of such a technology. The aim of this work is to contribute to the development of a low energy (5 keV) multibeam technology and to focus on the improvement of the LWR of the printed patterns. Several process parameters have been investigated to decrease the LWR: the effect of a specific writing strategy, the influence of the under layers and the introduction of post-lithographic treatments such as plasma treatments or thermal annealing. This work has shown that by combining a biased writing strategy with H2 plasma treatment, a 41% LWR decrease could be obtained. Although this performance is still above the ITRS requirements, this work opens the pace for LWR optimization with multi-beam lithography.
145

Interopérabilité de protocole de communication adaptatifs basse-consommation pour des réseaux de capteurs / Interoperability of adaptive low power consumption communication protocol for sensor networks

Morin, Elodie 24 April 2018 (has links)
L'essor rencontré par les différentes technologies dédiées aux réseaux de capteurs (WSN), a conduit au développement de plateformes capables d'opérer dans deux technologies différentes, adaptatives aux contextes de transmission. De telles plateformes ouvrent la porte à la conception de réseaux multitechnologies, que nous proposons d'exploiter dans le but de réduire la consommation d'énergie globale. Dans le but d'exploiter ces réseaux multitechnologies, nous décrivons les principales technologies de l'Internet des Objets (IoT), en les comparant sur un pied d'égalité grâce à l'analyseur que nous avons développé, puis les classifions en fonction des mécanismes MAC qu'elles exploitent. Nous analysons ensuite le lien entre le contexte applicatif (latence et fréquence de la génération de données) et le mécanisme MAC consommant le moins d'énergie pour ce contexte applicatif.Nous remarquons alors que les technologies exploitants un mécanisme MAC synchrone sont les plus adaptées aux trafics applicatifs périodiques dont les intervalles entre les générations de données sont courts. En effet, pour ces trafics, la dérive d'horloge entraine un coût de maintien de la synchronisation active trop élevé dans le cas de trafics périodiques rares. De plus, nous remarquons que la gestion des trafics applicatifs rares contraints en latence repose, dans les solutions existantes, sur l'utilisation d'une plateforme constamment active en mode de réception. Nous proposons alors d'exploiter les plateformes multitechnologies pour constituer un réseau synchrone dans lequel chaque nœud répartit son activité dans le temps pour globalement économiser de l'énergie pour remplacer le rôle du dispositif constamment disponible utilisé pour acheminer des trafics asynchrones contraints en latence. Nous remarquons que lors de la procédure d'attache au réseau synchrone, la situation du nœud qui tente de rejoindre un réseau synchrone dans le but d'y acheminer des données est similaire à la situation d'un nœud asynchrone qui souhaite acheminer des données au sein d'un réseau synchrone.Ainsi, nous proposons d'exploiter la phase d'attache au réseau pour acheminer des trafics émanants de noeuds asynchrones, contraints en latence, au sein d'un réseau synchrone.Cependant, les procédures actuellement standardisées d'attache au réseau sont naïves et très coûteuse en énergie, ce qui décourage l'utilisation d'un mode de communication asynchrone, reposant sur une succession d'associations/désassociations du réseau : nous proposons deux approches pour réduire le coût de cette procédure d'attache à un réseau TSCH. La première repose sur l'exploitation de séquences mathématiques dont la propriété est d'étaler les périodes d'activités dans le temps, tout en minimisant l'impact sur la latence de la procédure, pour diminuer le coût énergétique global de la procédure d'attache. La deuxième méthode proposée exploite les trames d'acquittement (ACK) des communications TSCH pour y ajouter des éléments d'informations : la date d'envoi de la prochaine trame de synchronisation sur le même canal physique que celui utilisé pour l'envoi de la trame d'ACK. Grâce au développement d'un simulateur des performances de la phase d'attache à un réseau TSCH, nous montrons que les protocole d'attaches proposés obtiennent de meilleures performances, soit en termes de latence, soit en termes de consommation d'énergie globale, que les protocoles d'attache classiquement utilisés dans les réseaux de capteurs.Enfin, nous proposons d'exploiter les mécanismes de la deuxième proposition d'attache au réseau pour l'envoi de trames de sollicitation à destination d'un nœud fonctionnant avec une technologie asynchrone, permettant ainsi d'acheminer un trafic asynchrone au sein d'un réseau synchrone en une latence bornée. Nous montrons la faisabilité et prouvons l'intérêt d'une telle proposition. / The growth of various technologies dedicated to sensor networks (WSN) has led to the development of platforms capable of operating in two different technologies, adaptive to transmission contexts. Such platforms open the door to the design of multi-technology networks, which we propose to exploit to reduce overall energy consumption. In order to exploit these multi-technology networks, we describe the main Internet of Things (IoT) technologies, comparing them on an equal footing thanks to the analyzer we developed, and classify them according to the MAC mechanisms they use. We then analyze the link between the application context (latency and frequency of data generation) and the MAC mechanism that consumes the least energy for this application context.We note that the technologies operating with a synchronous MAC mechanism are the most suitable for periodic application traffic with short intervals between data generation. For these traffic patterns, clock drift leads to extensive traffic overhead because of the need to actively maintain synchronization for sparse periodic traffic.Moreover, we notice that, in the existing solutions, the management of sparce application traffic management is based on the use of an always-on platform (in reception mode). We thus propose to exploit the multi-technology platforms to build a synchronous network in which each node distributes its activity over time to globally save energy by replacing the role of the always-on platform, while guaranteeing the delivery of the latency-constrained asynchronous traffic.We notice that during the synchronous network joining phase, the situation of the node attempting to join a synchronous network is similar to the situation of an asynchronous node wanting to deliver data through a synchronous network.Thus, we propose to exploit the synchronous network joining phase to route latency-constrained traffic originating from asynchronous nodes through the synchronous network.However, the currently standardised network attachment procedures are naïve and energy-greedy, which discourages the use of an asynchronous communication mode, based on a succession of network associations/dissociations: we thus propose two approaches to reduce the cost of the TSCH network attachment procedure.The first is based on the use of mathematical sequences wich distribute the periods of activity over time, while minimizing the impact on the latency of the procedure, in order to reduce the overall energy cost of the attachment procedure. The second proposed method exploits the acknowledgement frames (ACK) of TSCH data communications to embed the date of the next synchronization frame transmission on the same physical channel as the ACK frame. Thanks to the development of a simulator of the TSCH joining phase, we show that the proposed protocols achieve better performance, either in terms of joining latency, or in terms of overall energy consumption, than the standard joining protocols used in WSN.Finally, we propose to exploit the mechanisms of the second proposal for sending request frames to a node operating with an asynchronous technology, thus enabling asynchronous traffic to be routed through a synchronous network in bounded latency. We demonstrate the value and feasibility of such a proposal.
146

Návrh dispozičního řešení vícepodlažního bytového domu na území města České Budějovice / Proposed layout of a multi-storey apartment building on the territory of the town of České Budějovice.

SMUTNÁ, Michaela January 2011 (has links)
The thesis deals with a proposed layout of a multi-storey apartment building on the territory of the town of České Budějovice. The thesis contains a literary overview to inform the reader about the issues of design documents, analysis of the land use plan for the corporate town of České Budějovice in connection with the building location and, last but not least, related design documents in agreement with the applicable decree. The objective of this thesis was to develop the design documents meeting the low energy consumption standard, i.e. meeting all current requirements for modern and energy-saving construction projects, in terms of the appearance, employed technologies and materials. An integral part of the results is a placement of the project in a suitable location, as outlined by the land use plan. The thesis is concluded with an evaluation of the architectural and structural solution and of the selected materials in respect to the low energy consumption standard of the building.
147

Análise das tecnologias Bluetooth Low Energy e Zigbee em ambientes indoor para aplicações em internet das coisas

Sousa, Fernando Simplicio de January 2016 (has links)
Orientador: Prof. Dr. Ivan Roberto Santana Casella / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Engenharia Elétrica, 2016. / Atualmente existem diversos padrões de redes sem fio destinados ao monitoramento de sensores em aplicações de redes sem fio. O Bluetooth Low Energy (BLE) e o Zigbee são duas tecnologias em destaques que estão sendo amplamente empregadas em Smart Grids e Internet of Things (IOT) e foram desenvolvidas para o envio rápido de pequenos pacotes de dados em baixa latência com suporte a elevados números de nós operando em baixo consumo de energia. A degradação da potência de um sinal de rádio transmitido por dispositivos Bluetooth Low Energy e Zigbee pode ser ocasionada pela existência de objetos (paredes, portas, janelas e vegetações) que interferem na livre propagação do sinal eletromagnético. O objetivo deste trabalho foi analisar e comparar, através de uma modelagem computacional, os impactos da atenuação do sinal de rádio de redes sem fio BLE e Zigbee operando em ambiente indoor. Foram medidos os valores da potência do sinal recebido, relação sinal-ruído, taxa de dados e taxa de erro de bit estimada para diferentes fatores de perda de percurso e considerado o efeito de Shadowing.A modelagem computacional foi desenvolvida com auxílio do software OPNET Modeler e contemplou algoritmos que simulam as camadas PHY, MAC e enlace do BLE e do Zigbee, que permitiu analisar o comportamento das redes sem fio durante as trocas de pacotes de dados entre os dispositivos móveis. Além das simulações computacionais, foram feitos experimentos práticos com redes sem fio BLE e Zigbee localizadas em ambiente indoor em zona urbana. Os resultados das medições em campo foram comparadas e configuradas no modelagem computacional. Desta forma, foram criados modelos computacionais do BLE e Zigbee que descrevem parcialmente os mesmos comportamentos das redes sem fio ensaiadas nos experimentos práticos, o que tornou os resultados das simulações da modelagem computacional muito mais realistas. Através destes novos modelos computacionais, foi possível medir, comparar e analisar o desempenho das redes sem fio BLE e Zigbee em ambiente indoor. e da taxa de dados e provoca um aumento de BER à medida que o receptor se distância do transmissor em uma rede de dispositivos BLE e a adição do Shadowing tornou os resultados da modelagem computacional muito mais realista. Além das análises, este trabalho contribuiu com detalhes do desenvolvimento da modelagem computacional do BLE e Zigbee que foi realizado.Os resultados das simulações demonstraram que o aumento do fator de perda de percurso causou uma redução significativa da potência de recebimento e da taxa de dados e provoca um aumento de BER à medida que o receptor se distância do transmissor em uma rede de dispositivos BLE e a adição do Shadowing tornou os resultados da modelagem computacional muito mais realista. Além das análises, este trabalho contribuiu com detalhes do desenvolvimento da modelagem computacional do BLE e Zigbee que foi realizado. / Currently there are different standards of wireless networks for the sensors monitoring in wireless networking applications. Bluetooth Low Energy (BLE) and Zigbee are two technologies widely used in Smart Grids and Internet of Things (IOT) and were developed for the fast sending of small data packets at low latency with high numbers of nodes operating in low energy consumption. The degradation of the power of a radio signal transmitted by a BLE and Zigbee devices can be caused by the existence of objects, walls, doors, windows and vegetation, that interfere with the free propagation of electromagnetic signals. The objective of this work was to analyze and compare, through computer simulations, the radio signal attenuation of wireless networks BLE and Zigbee when operating in indoor environment. The value of the received signal strength, signal to noise ratio, data rate and bit error rate estimated for different path loss factors were measured and considered the effect of shadowing. The computer simulations was developed with the help of OPNET Modeler software, which included algorithms that simulate the PHY, MAC and Link Layer of the BLE and Zigbee, which allowed analyzing the behavior of wireless networks for the exchange of data packets between the mobile devices. In addition to the computer simulations were made practical experiments with wireless networks BLE and Zigbee located in indoor environment in urban areas. The results of field measurements were compared and set in computational modeling. Thus they were created computer models of BLE and Zigbee that describe partially the same behaviors of the tested wireless networks in the field via practical experiments, which made the simulation results of computer modeling more realistic. Through these new computer models were possible to measure, compare and analyze the performance of wireless networks BLE and Zigbee in indoor environment. The results of computer simulations have shown that increasing the path loss factor caused a significant reduction in received power and data rate and causes an increased BER when the receiver is away from the transmitter in a network BLE devices and adding the shadowing in computer simulations became more realistic results. In addition, this work contributed to the development details of computational modeling of BLE and Zigbee.
148

Efeitos de raios-X de baixa energia em células mamárias / Effects of low energy x-rays in mammary cells

Flávia Ventura dos Passos 12 August 2011 (has links)
Doses de radiação de baixa energia podem induzir quebras de dupla fita no DNA assim como também produzir perfis alterados de expressão de genes relacionados a estas lesões. Os danos não reparados ou mal reparados levam a uma maior suscetibilidade à transformação oncogênica já que os efeitos biológicos mais importantes causados pela radiação ionizante são mutação e carcinogênese. As lesões no DNA provocadas pela radiação podem também ocasionar o surgimento micronúcleos e as células podem ser induzidas à apoptose. O objetivo deste trabalho é estudar in vitro a presença de micronúcleos e a apoptose ocasionados por Raios-X de baixa energia. Pretende-se analisar estes efeitos biológicos em relação à energia equivalente à utilizada em exames mamográficos usando duas linhagens estabelecias de células de mama: a MCF-7 (tumoral) e a HB-2 (não-tumoral). As células, em crescimento exponencial, foram irradiadas no equipamento de arranjo experimental de mamografia do LCR/UERJ. A dose de 5Gy na energia de 30 kV foi aplicada com taxa de 0,1 Gy/seg utilizando filtro de 0,03 mm de molibdênio. As irradiações foram realizadas duas vezes, após as irradiações, as células foram incubadas por 4, 24 ou 48 horas e posteriormente coradas com o corante Hoechst33258 para análise em microscopia de fluorescência. Para cada análise, 1000 células foram categorizadas pela morfologia do núcleo. Os resultados mostraram que a HB-2, utilizada neste estudo como célula mamária normal, apresentou maior sensibilidade aos efeitos da radiação, com 37 % das células em apoptose após 4 hs de incubação, enquanto a MCF-7 apresentou 6,5 %. Nas análises após 24 hs foi possível confirmar a radioresistência da MCF-7 tendo sido observadas 11% de células em apoptose no grupo irradiado. Houve um aumento crescente de micronúcleos radioinduzidos nas duas linhagens de acordo com os tempos de incubação. Na análise de 4 hs a HB-2 apresentou 3%, em 24 hs, 8,5% e 48 hs, 11,5 %. Diante destes resultados, foi possível concluir que a energia do feixe de raios-X utilizada na mamografia pode ser capaz de ocasionar aumento de ocorrência de apoptose e geração de micronúcleos nas duas linhagens estudadas / Radiation doses of low-energy can induce double-stranded breaks in DNA as well resulting in altered profiles of gene expression related to these injuries. The damage is not repaired or poorly repaired leading to increased susceptibility to oncogenic transformation since most important biological effects caused by ionizing radiation are mutation and carcinogenesis. The DNA lesions caused by radiation can also provoke the presence of micronuclei and as result cells can be induced to apoptosis. The aim of this work is to perform a preliminary study "in vitro" to identify the presence of micronuclei caused by low energy. X-rays. It is intended analyze these biological effects caused by x-rays with energy equivalent to the ones used in mammography in two very well established breast: cell lines the MCF-7 (tumor) and HB-2 (non-tumor). Cells in exponential growth were irradiated using an experimental arrangement with a mammography tube of the LCR / UERJ. The dose of 5Gy was used for 30 kVp x-rays using 0.03 mm filter molybdenum with a fixed dose rate of 0.1 Gy / sec. The irradiations were repeated twice and. the cells were incubated for 4, 24 or 48 hours and stained with dye Hoechst 33258 for fluorescence microscopy analysis. For each analysis 1000 cells were categorized by the morphology of the nucleus. The results revealed that the HB-2, used in this study as normal mammary cell have showed high sensitivity to the effects of radiation, with 37% of cells undergoing apoptosis after incubation of 4hs, while MCF-7 showed 6.5%. In the 24 hour-analysis it was confirmed the radiation resistance of MCF-7 were it was observed 11% of cells in apoptosis in the irradiated group. There was an increasing number of radiation-induced micronuclei in both cell lines, according to the incubation times. After 4 hours, HB-2 presented 3% of micronuclei, in 24 hours, the experiment reveled 8.5%, and after 48 hours it increased to 11.5%. As result of this study we may conclude that the energy used in mammography is capable to cause an increase in incidence of apoptosis and in the production of micronuclei in both cell lines studied
149

Usage of Bluetooth Low Energy for Weather Measurements

Gustafsson, Viktor, Waller, Calle January 2018 (has links)
For every year the importance of lowering energy consumptionof our devices gets more important. Wireless devicesget smaller which leads to the fact that they need smallerbatteries than earlier versions. At the same time the customersstill have high requirements on the battery time. So what followsis that new technologies are needed to meet the customerrequirements by lowering the energy consumption for the devicesto maintain the same battery time as earlier.Today it is very common that these wireless devices makesuse of the wireless Bluetooth protocol in order to communicatewith other devices, for example with a mobile application.Bluetooth is in many cases more energy consuming thannecessary. In this report the wireless Bluetooth Low Energyprotocol will be tested and evaluated to see if the energy consumptionof a battery driven ground station for weather measurementscan be reduced.
150

Threats, Countermeasures, and Research Trends for BLE-based IoT Devices

January 2017 (has links)
abstract: The Internet of Things has conjured up a storm in the technology world by providing novel methods to connect, exchange, aggregate, and monitor data across a system of inter-related devices and entities. Of the myriad technologies that aid in the functioning of these IoT devices, Bluetooth Low Energy also known as BLE plays a major role in establishing inter-connectivity amongst these devices. This thesis aims to provide a background on BLE, the type of attacks that could occur in an IoT setting, the possible defenses that are available to prevent the occurrence of such attacks, and a discussion on the research trends that hold great promise in presenting seamless solutions to integrate IoT devices across different industry verticals. / Dissertation/Thesis / Masters Thesis Computer Science 2017

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