Dissertations / Theses on the topic 'Hybrid node'

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1

Rusu, Alexandrina Doina. "Synthesis and catalytic applications of carbene-functionalized hybrid catalysts." München Verl. Dr. Hut, 2009. http://mediatum2.ub.tum.de/node?id=737218.

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Reiner, Thomas. "Metalla affinity labels - a new route to organometallic enzyme hybrids." kostenfrei, 2009. http://mediatum2.ub.tum.de/node?id=685539.

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Ladha, Sonia. "Second Generation Immigrant Adaptation: Construction of a Hybrid Cultural Identity." ScholarWorks@UNO, 2005. http://louisdl.louislibraries.org/u?/NOD,194.

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Thesis (M.A.)--University of New Orleans, 2005.
Title from electronic submission form. "A thesis ... in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Sociology"--Thesis t.p. Vita. Includes bibliographical references.
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Baptista, Albano Manuel Cardoso. "Reconfigurable remote nodes for hybrid passive optical networks." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/2036.

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Mestrado em Engenharia Electrónica e Telecomunicações
O presente documento tem por objectivo demonstrar, analisar e optimizar nós remotos passivos para redes ópticas passivas baseadas numa topologia de anel de dupla fibra com multiplexagem no comprimento de onda onde estão penduradas árvores mono fibra baseadas na multiplexagem no tempo. A rede ‘Scalable Advanced Ring-based passive Dense Access Network Architecture’ (SARDANA) baseada nesta topologia é apresentada e demonstrada. Na rede SARDANA a interligação entre o anel e as árvores é realizada pelo intermédio de um nó especial denominado de nó remoto. Esse nó remoto é um elemento fundamental para o funcionamento, resiliência e escalabilidade da rede. Neste documento são apresentadas e comparadas diferentes topologias para a implementação desse nó remoto. É também apresentada a reconfigurabilidade remota desses mesmos nós remotos através de módulos de conversão energética e controlo, implementada nos nós remotos. Um factor importante para a optimização dos nós remotos é a amplificação remota realizada por intermédio de fibras dopadas de érbio pelo que o seu estudo é também apresentado. Finalmente é demonstrado um protótipo de um nó remotamente reconfigurado e eficiente. ABSTRACT: The objective of this document is to demonstrate, analyze and optimize remote nodes for passive optical networks based on double fiber ring multiplexed in wavelength connected to single fiber trees multiplexed in time. The network ‘Scalable Advanced Ring-based passive Dense Access Network Architecture’ (SARDANA) based on this topology is presented and demonstrated. In the SARDANA network the interconnection between the ring and the trees is done by means of a special node, the remote node. This node is a fundamental element to the operation, resiliency and scalability of the network. This document presents and compares different topologies to the implementation of the remote node. Remotely reconfigurability of the remote nodes is also demonstrated by means of optical conversion and control modules. An important factor to the optimization of the remote nodes is the remote amplification done by means of erbium doped fibers being presented the analysis of the amplifier. Finally is demonstrated a prototype of a node remotely reconfigured and efficient.
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5

Cui, Li. "Conducting polymer-based QCM-interdigitated electrode hybrid electronic nose system." Thesis, University of Glasgow, 1999. http://theses.gla.ac.uk/3974/.

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This research project was concerned with the establishment and characterisation of a quartz crystal microbalance (QCM) - conductimetric interdigitated electrode hybrid "second generation" Electronic Nose system. Research objectives covered a number of technical limitations and analytical difficulties existed in the "first generation" Electronic Nose system. A wide variety of work was carried out, including the design and fabrication of the electronic nose system, the optimisation of sensors response, the device modelling, the studies of vapour-polymer interaction mechanisms and the application of the electronic nose in multi-component analysis. A QCM-interdigitated electrode hybrid sensor odour measurement system was established, and sensor fabrication techniques developed. Some important parameters corresponding to sensor characteristics were investigated such as the conditions for polymer film polymerisation. By studying 16 different coatings, "optimal" individual initial resistances were proposed, which minimise long-term baseline resistance drift, whilst maintaining good sensitivity. A set of sensors was made with low initial resistance variation. Sensor detection dynamic range was found to be dependent on the type of the coating material and the film thickness. The response of a combined hybrid sensor pair remained stable during a test period of 45 days, which showed an improved stability. The principle of the sensor's response and device modelling were addressed. The vapour-polymer interactions and sensor pair's response were linked by a sensitivity coefficient (S), which was defined as the relative resistivity change by a single molecule absorbed into the polymer film. A pair of sensors showing concentration independence over a wide concentration range can be formed on separate QCM and interdigitated electrodes with the same polymer. The combined response (Srf) can be used to identify a particular vapour. Based on the concentration independence, the proposed "odour maps" showed the feasibility of distinguishing odourants using a significantly lower number of different types of sensor coatings. This demonstrated the improved selectivity of a hybrid system compared with the single property system.
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Megahed, Mohamed Helmy Mostafa. "SurvSec Security Architecture for Reliable Surveillance WSN Recovery from Base Station Failure." Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31154.

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Surveillance wireless sensor networks (WSNs) are highly vulnerable to the failure of the base station (BS) because attackers can easily render the network useless for relatively long periods of time by only destroying the BS. The time and effort needed to destroy the BS is much less than that needed to destroy the numerous sensing nodes. Previous works have tackled BS failure by deploying a mobile BS or by using multiple BSs, which requires extra cost. Moreover, despite using the best electronic countermeasures, intrusion tolerance systems and anti-traffic analysis strategies to protect the BSs, an adversary can still destroy them. The new BS cannot trust the deployed sensor nodes. Also, previous works lack both the procedures to ensure network reliability and security during BS failure such as storing then sending reports concerning security threats against nodes to the new BS and the procedures to verify the trustworthiness of the deployed sensing nodes. Otherwise, a new WSN must be re-deployed which involves a high cost and requires time for the deployment and setup of the new WSN. In this thesis, we address the problem of reliable recovery from a BS failure by proposing a new security architecture called Surveillance Security (SurvSec). SurvSec continuously monitors the network for security threats and stores data related to node security, detects and authenticates the new BS, and recovers the stored data at the new BS. SurvSec includes encryption for security-related information using an efficient dynamic secret sharing algorithm, where previous work has high computations for dynamic secret sharing. SurvSec includes compromised nodes detection protocol against collaborative work of attackers working at the same time where previous works have been inefficient against collaborative work of attackers working at the same time. SurvSec includes a key management scheme for homogenous WSN, where previous works assume heterogeneous WSN using High-end Sensor Nodes (HSN) which are the best target for the attackers. SurvSec includes efficient encryption architecture against quantum computers with a low time delay for encryption and decryption, where previous works have had high time delay to encrypt and decrypt large data size, where AES-256 has 14 rounds and high delay. SurvSec consists of five components, which are: 1. A Hierarchical Data Storage and Data Recovery System. 2. Security for the Stored Data using a new dynamic secret sharing algorithm. 3. A Compromised-Nodes Detection Algorithm at the first stage. 4. A Hybrid and Dynamic Key Management scheme for homogenous network. 5. Powerful Encryption Architecture for post-quantum computers with low time delay. In this thesis, we introduce six new contributions which are the followings: 1. The development of the new security architecture called Surveillance Security (SurvSec) based on distributed Security Managers (SMs) to enable distributed network security and distributed secure storage. 2. The design of a new dynamic secret sharing algorithm to secure the stored data by using distributed users tables. 3. A new algorithm to detect compromised nodes at the first stage, when a group of attackers capture many legitimate nodes after the base station destruction. This algorithm is designed to be resistant against a group of attackers working at the same time to compromise many legitimate nodes during the base station failure. 4. A hybrid and dynamic key management scheme for homogenous network which is called certificates shared verification key management. 5. A new encryption architecture which is called the spread spectrum encryption architecture SSEA to resist quantum-computers attacks. 6. Hardware implementation of reliable network recovery from BS failure. The description of the new security architecture SurvSec components is done followed by a simulation and analytical study of the proposed solutions to show its performance.
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7

Shin, Hyun Woo. "A hybrid electronic nose system for monitoring the quality of potable water." Thesis, University of Warwick, 1999. http://wrap.warwick.ac.uk/111031/.

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This PhD thesis reports on the potential application of an electronic nose to analysing the quality of potable water. The enrichment of water by toxic cyanobacteria is fast becoming a severe problem in the quality of water and a common source of environmental odour pollution. Thus, of particular interest is the classification and early warning of toxic cyanobacteria in water. This research reports upon the first attempt to identify electronically cyanobacteria in water. The measurement system comprises a Cellfacts instrument and a Warwick e-nose specially constructed for the testing of the cyanobacteria in water. The Warwick e- nose employed an array of six commercial odour sensors and was set-up to monitor not only the different strains, but also the growth phases, of cyanobacteria. A series of experiments was carried out to analyse the nature of two closely related strains of cyanobacteria, Microcystis aeruginosa PCC 7806 which produces a toxin and PCC 7941 that does not. Several pre-processing techniques were explored in order to remove the noise factor associated with running the electronic nose in ambient air, and the normalised fractional difference method was found to give the best PCA plot. Three supervised neural networks, MLP, LVQ and Fuzzy ARTMAP, were used and compared for the classification of both two strains and four different growth phases of cyanobacteria (lag, growth, stationary and late stationary). The optimal MLP network was found to classify correctly 97.1 % of unknown non-toxic and 100 % of unknown toxic cyanobacteria. The optimal LVQ and Fuzzy ARTMAP algorithms were able to classify 100% of both strains of cyanobacteria. The accuracy of MLP, LVQ and Fuzzy ARTMAP algorithms with 4 different growth phases of toxic cyanobacteria was 92.3 %, 95.1 % and 92.3 %, respectively. A hybrid e-nose system based on 6 MOS, 6 CP, 2 temperature sensors, 1 humidity sensor and 2 flow sensors was finally developed. Using the hybrid system, data were gathered on six different cyanobacteria cultures for the classification of growth phase. The hybrid resistive nose showed high resolving power to discriminate six growth stages as well as three growth phases. Even though time did not permit many series of the continuous monitoring, because of the relatively long life span (30-40 days) of cyanobacteria, improved results indicate the use of a hybrid nose. The HP 4440 chemical sensor was also used for the discrimination of six different cyanobacteria samples and the comparison with the electronic nose. The hybrid resistive nose based on 6 MOS and 6 CP showed a better resolving power to discriminate six growth stages as well as three growth phases than the HP 4440 chemical sensor. Although the mass analyser detects individual volatile chemicals accurately, it proves no indication of whether the volatile is an odour. The results demonstrate that it is possible to apply the e-nose system for monitoring the quality of potable water. It would be expected that the hybrid e-nose could be applicable to a large number of applications in health and safety with a greater flexibility.
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8

Beidalah, Chadrick J. Coudray Aaron D. "The technologies and principles needed for the powering of remote nodes in an interoperability network." Monterey, Calif. : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/March/09Mar%5FBeidalah.pdf.

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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, March 2009.
Thesis Advisor(s): Buddenberg, Rex. "March 2009." Description based on title screen as viewed on April 24, 2009. Author(s) subject terms: Power Generation, Remote Network Node, Interoperability Network, Electric Generator, Wind Power, Solar Power, Photovoltaic, Thermoelectric, Energy Storage, Fuel Cell, Hybrid Power, Power Monitoring, Power Management. Includes bibliographical references (p. 117-120). Also available in print.
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9

Ru, Jifeng. "Adaptive estimation and detection techniques with applications." ScholarWorks@UNO, 2005. http://louisdl.louislibraries.org/u?/NOD,285.

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Thesis (Ph. D.)--University of New Orleans, 2005.
Title from electronic submission form. "A dissertation ... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Engineering and Applied Science"--Dissertation t.p. Vita. Includes bibliographical references.
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10

Liu, Xing. "Hybrid real-time operating system integrated with middleware for resource-constrained wireless sensor nodes." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22472/document.

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Avec les avancées récentes en microélectronique, en traitement numérique et en technologie de communication, les noeuds de réseau de capteurs sans fil (noeud RCSF) deviennent de moins en moins encombrants et coûteux. De ce fait la technologie de RCSF est utilisée dans de larges domaines d’application. Comme les noeuds RCSF sont limités en taille et en coût, ils sont en général équipés d’un petit microcontrôleur de faible puissance de calcul et de mémoire etc. De plus ils sont alimentés par une batterie donc son énergie disponible est limitée. A cause de ces contraintes, la plateforme logicielle d’un RCSF doit consommer peu de mémoire, d’énergie, et doit être efficace en calcul. Toutes ces contraintes rendent les développements de logiciels dédiés au RCSF très compliqués. Aujourd’hui le développement d’un système d’exploitation dédié à la technologie RCSF est un sujet important. En effet avec un système d’exploitation efficient, les ressources matérielles d’une plateforme RCSF peuvent être utilisées efficacement. De plus, un ensemble de services système disponibles permet de simplifier le développement d’une application. Actuellement beaucoup de travaux de recherche ont été menés pour développer des systèmes d’exploitation pour le RCSF tels que TinyOS, Contiki, SOS, openWSN, mantisOS et simpleRTJ. Cependant plusieurs défis restent à relever dans le domaine de système d’exploitation pour le RCSF. Le premier des défis est le développement d’un système d’exploitation temps réel à faible empreinte mémoire dédié au RCSF. Le second défi est de développer un mécanisme permettant d’utiliser efficacement la mémoire et l’énergie disponible d’un RCSF. De plus, comment fournir un développement d’application pour le RCSF reste une question ouverte. Dans cette thèse, un nouveau système d’exploitation hybride, temps réel à énergie efficiente et à faible empreinte mémoire nommé MIROS dédié au RCSF a été développé. Dans MIROS, un ordonnanceur hybride a été adopté ; les deux ordonnanceurs évènementiel et multithread ont été implémentés. Avec cet ordonnanceur hybride, le nombre de threads de MIROS peut être diminué d’une façon importante. En conséquence, les avantages d’un système d’exploitation évènementiel qui consomme peu de ressource mémoire et la performance temps réel d’un système d’exploitation multithread ont été obtenues. De plus, l’allocation dynamique de la mémoire a été aussi réalisée dans MIROS. La technique d’allocation mémoire de MIROS permet l’augmentation de la zone mémoire allouée et le réassemblage des fragments de mémoire. De ce fait, l’allocation de mémoire de MIROS devient plus flexible et la ressource mémoire d’un noeud RCSF peut être utilisée efficacement. Comme l’énergie d’un noeud RCSF est une ressource à forte contrainte, le mécanisme de conservation d’énergie a été implanté dans MIROS. Contrairement aux autres systèmes d’exploitation pour RCSF où la conservation d’énergie a été prise en compte seulement en logiciel, dans MIROS la conservation d’énergie a été prise en compte à la fois en logiciel et en matériel. Enfin, pour fournir un environnement de développement convivial aux utilisateurs, un nouveau intergiciel nommé EMIDE a été développé et intégré dans MIROS. EMIDE permet le découplage d’une application de système. Donc le programme d’application est plus simple et la reprogrammation à distance est plus performante, car seulement les codes de l’application seront reprogrammés. Les évaluations de performance de MIROS montrent que MIROS est un système temps réel à faible empreinte mémoire et efficace pour son exécution. De ce fait, MIROS peut être utilisé dans plusieurs plateformes telles que BTnode, IMote, SenseNode, TelosB et T-Mote Sky. Enfin, MIROS peut être utilisé pour les plateformes RCSF à fortes contraintes de ressources
With the recent advances in microelectronic, computing and communication technologies, wireless sensor network (WSN) nodes have become physically smaller and more inexpensive. As a result, WSN technology has become increasingly popular in widespread application domains. Since WSN nodes are minimized in physical size and cost, they are mostly restricted to platform resources such as processor computation ability, memory resources and energy supply. The constrained platform resources and diverse application requirements make software development on the WSN platform complicated. On the one hand, the software running on the WSN platform should be small in the memory footprint, low in energy consumption and high in execution efficiency. On the other hand, the diverse application development requirements, such as the real-time guarantee and the high reprogramming performance, should be met by the WSN software. The operating system (OS) technology is significant for the WSN proliferation. An outstanding WSN OS can not only utilize the constrained WSN platform resources efficiently, but also serve the WSN applications soundly. Currently, a set of WSN OSes have been developed, such as the TinyOS, the Contiki, the SOS, the openWSN and the mantisOS. However, many OS development challenges still exist, such as the development of a WSN OS which is high in real-time performance yet low in memory footprint; the improvement of the utilization efficiency to the memory and energy resources on the WSN platforms, and the providing of a user-friendly application development environment to the WSN users. In this thesis, a new hybrid, real-time, energy-efficient, memory-efficient, fault-tolerant and user-friendly WSN OS MIROS is developed. MIROS uses the hybrid scheduling to combine the advantages of the event-driven system's low memory consumption and the multithreaded system's high real-time performance. By so doing, the real-time scheduling can be achieved on the severely resource-constrained WSN platforms. In addition to the hybrid scheduling, the dynamic memory allocators are also realized in MIROS. Differing from the other dynamic allocation approaches, the memory heap in MIROS can be extended and the memory fragments in the MIROS can be defragmented. As a result, MIROS allocators become flexible and the memory resources can be utilized more efficiently. Besides the above mechanisms, the energy conservation mechanism is also implemented in MIROS. Different from most other WSN OSes in which the energy resource is conserved only from the software aspect, the energy conservation in MIROS is achieved from both the software aspect and the multi-core hardware aspect. With this conservation mechanism, the energy cost reduced significantly, and the lifetime of the WSN nodes prolonged. Furthermore, MIROS implements the new middleware software EMIDE in order to provide a user-friendly application development environment to the WSN users. With EMIDE, the WSN application space can be decoupled from the low-level system space. Consequently, the application programming can be simplified as the users only need to focus on the application space. Moreover, the application reprogramming performance can be improved as only the application image other than the monolithic image needs to be updated during the reprogramming process. The performance evaluation works to the MIROS prove that MIROS is a real-time OS which has small memory footprint, low energy cost and high execution efficiency. Thus, it is suitable to be used on many WSN platforms including the BTnode, IMote, SenseNode, TelosB, T-Mote Sky, etc. The performance evaluation to EMIDE proves that EMIDE has less memory cost and low energy consumption. Moreover, it supports small-size application code. Therefore, it can be used on the high resource-constrained WSN platforms to provide a user-friendly development environment to the WSN users
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11

PEPPAS, NIKOLAOS. "A HYBRID ROUTING PROTOCOL FOR COMMUNICATIONS AMONG NODES WITHHIGH RELATIVE SPEED IN WIRELESS MESH NETWORKS." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2345.

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Wireless mesh networks (WMN) is a new promising wireless technology which uses already available hardware and software components. This thesis proposes a routing algorithm for military applications. More specifically, a specialized scenario consisting of a network of flying Unmanned Aerial Vehicles (UAVs) executing reconnaissance missions is investigated. The proposed routing algorithm is hybrid in nature and uses both reactive and proactive routing characteristics to transmit information. Through simulations run on a specially built stand alone simulator, based on Java, packet overhead, delivery ratio and latency metrics were monitored with respect to varying number of nodes, node density and mobility. The results showed that the high overhead leads to high delivery ratio while latency tends to increase as the network grows larger. All the metrics revealed sensitivity in high mobility conditions.
M.S.Cp.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Computer Engineering MSCpE
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12

Marchini, Andrea. "Performance evaluation of improved output scheduling in 3lihon nodes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/6435/.

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Le reti ottiche, grazie alla loro elevata capacità, hanno acquisito sempre maggiore importanza negli ultimi anni, sia per via del crescente volume di dati scambiati, legato soprattutto alla larga diffusione di Internet, sia per la necessità di comunicazioni in tempo reale. Dati i (relativamente) lunghi tempi di adattamento, questa tecnologia nativamente non è quella ottimale per il trasporto di un traffico a burst, tipico delle telecomunicazioni odierne. Le reti ibride cercano, quindi, di coniugare al meglio le potenzialità della commutazione ottica di circuito e della commutazione ottica a pacchetto. In questo lavoro, in particolare, ci si è concentrati su un'architettura di rete ibrida denominata 3LIHON (3-Level Integrated Hybrid Optical Network). Essa prevede tre distinti livelli di qualità di servizio (QoS) per soddisfare differenti necessità: - Guaranteed Service Type (GST): simile ad un servizio a commutazione di circuito, non ammette perdita di dati. - Statistically Multiplexed Real Time (SM/RT): simile ad un servizio a commutazione di pacchetto, garantisce ritardo nullo o molto basso all'interno della rete, permette un piccolo tasso di perdita di dati e ammette la contesa della banda. - Statistically Multiplexed Best Effort (SM/BE): simile ad un servizio a commutazione di pacchetto, non garantisce alcun ritardo tra i nodi ed ammette un basso tasso di perdita dei dati. In un nodo 3LIHON, il traffico SM/BE impossibile da servire, a causa ad es. dell'interruzione da parte di pacchetti aventi un livello di QoS più prioritario, viene irrimediabilmente perso. Questo implica anche lo spreco del tempo e delle risorse impiegati per trasmettere un pacchetto SM/BE fino alla sua interruzione. Nel presente lavoro si è cercato di limitare, per quanto possibile, questo comportamento sconveniente, adottando e comparando tre strategie, che hanno portato alla modifica del nodo 3LIHON standard ed alla nascita di tre sue varianti.
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Pessoa, Lucio Flavio Cavalcanti. "Nonlinear systems and neural networks with hybrid morphological/rank/linear nodes : optimal design and applications to image processing and pattern recognition." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/13519.

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14

Gonçalves, Vanessa Santos Silva. "Overcoming Central Nervous System-barriers by the development of hybrid structured systems for nose-to-brain drug delivery using clean technologies." Doctoral thesis, Universidade Nova de Lisboa, Instituto de Tecnologia Química e Biológica António Xavier, 2016. http://hdl.handle.net/10362/56395.

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The effective delivery of therapeutics into the brain is challenging since drugs or drug delivery systems (DDS) candidates are not able to cross the blood-brain barrier (BBB), making the development of new drugs alone not enough to ensure progresses in Central Nervous System (CNS) drug therapy. Due to several problems related with other routes of brain drug administration, the interest has increased towards exploring the possibility of intranasal administration. The nose-to-brain transport and the therapeutic viability of this route have been investigated for rapid and effective transport of drugs to CNS, but the development of nasal drug products for brain targeting is still faced with many challenges.(...)
info:eu-repo/semantics/publishedVersion
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Wiziack, Nadja Karolina Leonel. "Desenvolvimento de sistemas multissensoriais híbridos, língua e narizes eletrônicos para a avaliação de combustíveis." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/3/3140/tde-21102010-104248/.

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A utilização simultânea de diferentes tecnologias de sensores é um método eficiente para aumentar o desempenho de sistemas sensoriais. Com o intuito de contribuir para um melhor controle da qualidade de combustíveis brasileiros, foram desenvolvidos neste trabalho sensores para serem utilizados em Língua e Narizes Eletrônicos. Estes sistemas multissensoriais foram utilizados separadamente, bem como simultaneamente, integrando-os para a avaliação da qualidade de gasolina e etanol. Desse modo, foram fabricados dois tipos de sistemas multissensoriais híbridos. O primeiro sistema foi composto pela integração de uma Língua Eletrônica (LE) e de um Nariz Eletrônico (NE), denominado SH-1. Neste sistema multissensorial, a impedância elétrica do conjunto dos diferentes sensores, baseados em filmes nanoestruturados de diferentes polímeros condutores depositados sobre diferentes microeletrodos de ouro, foi medida simultaneamente no líquido e no vapor de amostras de combustíveis. Já o segundo sistema multissensorial híbrido, SH-2, foi composto pela união de dois tipos de NEs e foi fabricado integrando sensores produzidos a partir de microbalanças de quartzo e de uma matriz de capacitores, ambos funcionalizados com os mesmos materiais sensoativos, polímeros condutores e metaloporfirinas. A frequência de oscilação do cristal de quartzo, bem como a capacitância da matriz de capacitores foram medidas no vapor de combustíveis. Estes sistemas híbridos são de fácil fabricação, simples operação e sensíveis a uma grande variedade de substâncias químicas de interesse. Foram empregadas ferramentas de análise multivariada de dados para a calibração e validação dos sensores, bem como para a interpretação dos resultados obtidos.
The simultaneous use of different sensor technologies is an efficient method to increase the performance of sensor systems. Aiming to contribute to a better quality control of Brazilian fuels, sensors were developed in this work to be used in electronic tongue and electronic noses. These multisensor systems were used separately and simultaneously integrating them to evaluation the quality of gasoline and ethanol. Thus, two types of multisensor hybrid systems were manufactured. The first system was composed by the integration of an Electronic Tongue (LE) and an Electronic Nose (NE), called SH-1. In this multisensor system, the electrical impedance of all the different sensors, based on nanostructured films of conducting polymers deposited on different gold microelectrodes, was measured simultaneously in both liquid and vapor fuel samples. The second multisensor hybrid system, SH-2, was composed by the union of two types of NEs and was fabricated by integrating sensors made from quartz microbalance and an array of capacitors, both functionalized with the same sensitive materials, conducting polymers and metalloporphyrins. The oscillation frequency of quartz crystal, and the capacitance of the array of capacitors were measured in the fuel vapor. These hybrid systems are easy to fabricate, simple to operate and sensitive to a wide variety of chemicals of interest. Tools for multivariate analysis were used for calibration and validation of the sensors, as well as for the interpretation of results.
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Andriankaja, Andry. "La régulation transcriptionnelle du gène MtENOD11 au cours des endosymbioses racinaires : caractérisation des éléments cis-régulateurs spécifiques de la réponse aux facteurs Nod." Toulouse 3, 2006. http://www.theses.fr/2006TOU30033.

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Nous avons réalisé une analyse fonctionnelle détaillée du promoteur du gène MtENOD11 au cours des infections endosymbiotiques et en réponse aux signaux spécifiques secretés par Rhizobium appelés facteurs Nod (FNods) qui jouent un rôle clé dans l'établissement de la syymbiose fixatrice d'azote. Nous avons identifié une région promotrice de 257 pb suffisante pour diriger une expression au cours de l'infection par Rhizobium, et de l'association endoymcorhizienne et lors de l'interaction parasitaire avec les nématodes à galles Meloidogyne incognita. Nous avons caractérisé un motif riche en AT requis à la fois pour l'expression associée à l'infection par Rhizobium et par les endomycorhizes, montrant pour la première fois des mécanismes similaires de régulation lors des infections endosymbiotiques raciniares. Nous avons ensuite caractérisé pour la première fois une unité régulatrice originale (appelée NF-box) suffisante pour conférer une expression dépendante des FNods et épiderme-spécifique. Nous avons également démontré qu'au moins trois sites de liaison de facteurs trans sont importants pour cette réponse. Enfin, nous avons initié des approches gènes candidats et un criblage simple hybride chez la levure pour identifier les facteurs trans impliqués dans l'activation de gènes par les Fnods
We have undertaken a detailed functional analysis of Medicago truncatula ENOD11 gene promoter during endosymbiotic infections and in response to specific rhizobial signals known as Nod factors (NFs), which play a key role in the establishment of the N-fixing symbiosis. First, we defined a 257 bp promoter sequence sufficient to direct expression during rhizobial infection, arbuscular endomycorrhizal (AM) fungi association and Meloidogyne incognita parasitic root knot nematode interaction. We characterized an AT-rich motif required for both rhizobial- and mycorrhizal-related infection, thus providing the first direct evidence for similarities in gene regulatory mechanisms during endosymbiotic root colonization. Subsequently, we were able to define a 33 bp novel regulatory unit (named NF-box), sufficient to confer NF-dependent, epidermal-specific expression. We further demonstrated that the NF-box unit comprises at least three adjacent trans-factor binding motifs which are important for this response. Finally, we initiated yeast one-hybrid screening and candidate gene approach to identify trans-factors involved in NF-mediated activation
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17

Haddi, Zouhair. "Conception et développement d'un système multicapteurs en gaz et en liquide pour la sécurité alimentaire." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10292/document.

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Les systèmes de nez et de langues électroniques à base de capteurs chimiques et électrochimiques constituent une solution avantageuse pour la caractérisation des odeurs et des saveurs émanant des produits agroalimentaires. La sélectivité croisée de la matrice des capteurs couplée aux méthodes de reconnaissance de formes est l'élément clé dans la conception et le développement de ces systèmes. Dans cette optique, nous avons démontré la capacité d'un dispositif expérimental de nez électronique à discriminer entre les différents types de drogues, à analyser la fraîcheur des fromages, à identifier entre les fromages adultérés et à différentier entre les eaux potables et usées. Nous avons également réussi à classifier correctement les eaux potables (minérales, de source, gazeuse et de robinet) et usées par utilisation d'une langue électronique potentiométrique. Cette étude a été validée par la Chromatographie en Phase Gazeuse couplée à la Spectrométrie de Masse (CPG-MS). En outre, nous avons développé une langue électronique voltammétrique à base d'une électrode de Diamant Dopé au Bore pour différencier les phases de traitement des eaux usées domestiques et hospitaliers et pour identifier les différents métaux lourds (Pb, Hg, Cu, Cd, Ni et le Zn) contenus dans l'eau du fleuve Rhône. La Voltammétrie à Redissolution Anodique à Impulsion Différentielle (DPASV) a été utilisée comme une méthode électrochimique pour caractériser les eaux étudiées. Enfin, les systèmes multicapteurs hybrides se sont avérés un bon outil analytique pour caractériser les produits de l'industrie agroalimentaire tels que les jus tunisiens et les huiles d'olives marocaines
Electronic noses and tongues systems based on chemical and electrochemical sensors are an advantageous solution for the characterisation of odours and tastes that are emanating from food products. The cross-selectivity of the sensor array coupled with patter recognition methods is the key element in the design and development of these systems. In this context, we have demonstrated the ability of an electronic nose device to discriminate between different types of drugs, to analyse cheeses freshness, to identify adulterated cheeses and to differentiate between potable and wastewaters. We have also succeeded to correctly classify drinking waters (mineral, natural, sparkling and tap) and wastewaters by using a potentiometric electronic tongue. This study was validated by Gas Chromatography coupled with Mass Spectrometry (GC-MS). Furthermore, we have developed a voltammetric electronic tongue based on a Diamond Doped Boron electrode to differentiate treatment stages of domestic and hospital wastewaters and to identify different heavy metals (Pb, Hg, Cu, Cd, Ni and Zn) contained in Rhône river. The Differential Pulse Anodic Stripping Voltammetry (DPASV) was used as an electrochemical method to characterise the studied waters. Finally, the hybrid multisensor systems have proven to be good analytical tools to characterise the products of food industry such as Tunisian juices and Moroccan olive oils
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18

FEDERICO, LUCA. "L'apprendistato letterario di Raffaele La Capria." Doctoral thesis, Università degli studi di Genova, 2020. http://hdl.handle.net/11567/1005664.

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Superati «novant’anni d’impazienza» e dopo un lungo periodo votato all’autocommento e all’esplorazione delle proprie intenzioni, Raffaele La Capria ha raccolto le sue opere in due Meridiani curati da Silvio Perrella. La Capria ne ha celebrato l’uscita nella prolusione inaugurale di Salerno Letteratura, poi confluita nel breve autoritratto narrativo "Introduzione a me stesso" (2014). In questa sede, l’autore è tornato su alcuni punti essenziali della sua riflessione sulla scrittura, come la relazione, reciproca e ineludibile, fra tradizione e contemporaneità. All’epilogo del «romanzo involontario» di una vita, La Capria guarda retrospettivamente alla propria esperienza come ad un’autentica educazione intellettuale. Perciò, muovendo da un’intervista inedita del 2015, riportata integralmente in appendice, la tesi ha l’obiettivo di ricostruire l’apprendistato letterario di La Capria dai primi anni Trenta, quando l’autore ancora frequentava il ginnasio, fino all’inizio dei Sessanta, quando ottenne il premio che ne avrebbe assicurato il successo. Il percorso, che riesamina l’intera bibliografia lacapriana nella sua varietà e nella sua stratificazione, si articola in una serie di fasi interdipendenti: la partecipazione indiretta alle iniziative dei GUF (intorno alle riviste «IX maggio» e «Pattuglia»); l’incursione nel giornalismo e l’impegno culturale nell’immediato dopoguerra (sulle pagine di «Latitudine» e di «SUD»); l’attività di traduttore dal francese e dall’inglese (da André Gide a T.S. Eliot); l’impiego alla RAI come autore e conduttore radiofonico (con trasmissioni dedicate a Orwell, Stevenson, Saroyan e Faulkner); la collaborazione con «Il Gatto Selvatico», la rivista dell’ENI voluta da Enrico Mattei e diretta da Attilio Bertolucci; e le vicende editoriali dei suoi primi due romanzi, “Un giorno d’impazienza” (1952) e “Ferito a morte” (1961), fino alla conquista dello Strega. La rilettura dell’opera di uno scrittore semi-autobiografico come La Capria, attraverso il costante riscontro di fonti giornalistiche, testimonianze epistolari e documenti d’archivio che avvalorano e occasionalmente smentiscono la sua versione dei fatti, diventa allora un’occasione per immergersi nella sua mitografia personale e avventurarsi in territori finora poco esplorati: come la ricostruzione del suo profilo culturale, a partire dal milieu in cui La Capria vive e opera, o l’incidenza delle letture e delle esperienze giovanili sulla sua prassi letteraria.
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19

Liu, Kevin, and 劉書煒. "Analysis of Node Density_Based Hybrid Clustering Routing in Ad-Hoc Networks." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/18274320374765013452.

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碩士
元智大學
資訊工程學系
89
The existing clustering algorithms for Ad Hoc wireless networks are monolithic in that they don’t change clustering rules according to different node density. This monolithic property cannot achieve good network stability in different network conditions. This thesis propose a hybrid clustering algorithm and routing protocol(HCRP) based on node density. Our algorithm integrates the ZRP and CCH clustering algorithm and divides the network into zones as used in ZHLS. Based on the node density of each zone, each zone applies different either ZRP or CCH to do clustering. Simulation results show that HCRP performances better than ZRP and CCH in term of cost efficiency in networks stability.
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20

Petela, Karolina. "Analysis of solar energy application into hybrid heat nodes." Doctoral thesis, 2019. http://hdl.handle.net/2158/1157274.

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A doctoral thesis prepared under the supervision of Prof. G. Manfrida from University of Florence and Prof. A. Szlęk from Silesian University of Technology. Dissertation was prepared in the frame of a double doctoral degree agreement. The work is focused on investigating the energy and exergy consumption indicators that may be caused by exploiting solar assisted cooling installations of two different types working under two different meteorological conditions.
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21

Antunes, André Mendes. "A Smart IoT Node using a Hybrid Edge-Computing Strategy for Environmental Multiparameter Sensing." Master's thesis, 2021. http://hdl.handle.net/10362/127801.

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The Internet of Things (IoT) has been growing at an immense pace over the last few years and there are no predictions of slowing down anytime soon, but most importantly, not only has it been growing in size but it has also been growing in capabilities, performance and diversity. Diversity is incredibly important but also fracturing, in this context. As IoT sensor nodes get more performant and diverse, their adaptability and reconfigurability ends up being lost in the search for ultimate performance. As a way to unify these individual single purpose sensor nodes, a need and an opportunity present themselves to develop a singular multi-parameter, multi-sensor IoT node, that can make use of the latest reconfigurable technology to adapt itself to the requirements of each type of sensor, while maintaining the very high performance and precision of dedicated sensor nodes. This dissertation work will thus focus on developing an architecture and building a prototype circuit board for a multi-sensor, reconfigurable IoT node based on a state-ofthe- art System-on-Chip (SoC) with extremely high resolution measurement capabilities, which can interface with virtually any type of existing sensor. This architecture and prototype are intended to serve as a stepping stone in the path to develop a capable IoT node which can interface with a wider range of sensor and have a higher precision than what is currently available
A Internet of Things (IoT) tem vindo a crescer a passos largos ao longo dos últimos anos, e não apresenta quaisquer sinais de abrandar o seu crescimento num futuro próximo. No entanto, não só tem vindo a crescer em tamanho, mas também nas suas capacidades, performance e diversidade. Enquanto que a diversidade é extremamente importante, neste contexto, é também fraturante. À medida que os nós IoT melhoram em performance e diversidade, a sua adaptabilidade e reconfigurabiliade acaba por ficar em segundo plano na procura do pico de performance. Com o objetivo de unificar estes nós de sensores com propósitos singulares, apresentase uma oportunidade e uma necessidade de desenvolver um único nó IoT capaz de fazer interface com uma multiplicidade de sensores distintos, usando tecnologia de ponta reconfigurável para se adaptar às necessidades de cada tipo de sensor, mantendo ainda assim a alta performance e precisão de nós de sensor dedicados. A presente dissertação irá então focar-se no desenvolvimento de uma arquitetura de sistema e criação de um protótipo em placa de circuito impresso referente a um nó IoT multisensor reconfigurável, baseado num SoC de última geração com capacidades de medição extremamente elevadas, que consiga fazer interface com qualquer tipo de sensor existente. Esta arquitetura de sistema e protótipo são desenvolvidos com a intenção de servirem como ponto de partida para o desenvolvimento de um nó IoT de interface com sensores, que tenha a capacidade de medir qualquer tipo de sensor com uma precisão superior àquilo que está atualmente disponível.
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22

Page, Jonathan Grant. "Energy efficient hybrid routing protocol for wireless sensor networks." Diss., 2008. http://hdl.handle.net/2263/27724.

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A wireless sensor network is designed to monitor events and report this information to a central location, or sink node. The information is required to efficiently travel through the network. It is the job of the routing protocol to officiate this process. With transmissions consuming the majority of the energy available to a sensor node, it becomes important to limit their usage while still maintaining reliable communication with the sink node. The aim of the research covered in this dissertation was to adapt the flat and hierarchical architectures to create a new hybrid that draws on current protocol theories. The designed and developed protocol, Hybrid Energy Efficient Routing (HEER) protocol, builds upon the initial groundwork laid out by the previously developed Simple Energy Efficient Routing (SEER) protocol designed by C.J. Leuschner. Another aspect of the work was to focus on the current lack of credibility that is present in the WSN research community. The validity of SEER was examined and tested and this led to the main focus of this research, ensuring that HEER proves to be valid. The HEER protocol for wireless sensor networks is designed such that it is computationally simple, limits the number of transmissions, employs a cross-layer approach, is reliable, is energy-aware, has limited support for mobile nodes, is energy efficient, and most importantly is credible. Sensor nodes are extremely limited when it comes to their available energy resources. To maximise the node and network lifetimes requires the designed algorithm to be energy aware and as efficient as possible. A cross-layer design approach is followed which allows for the different layers of the OSI model to interact. The HEER protocol limits the number of transmissions that are used for network operation. This is achieved by using a minimal amount of messages for network setup and by selecting the optimal route. Route selection is calculated using hop count, current energy available, energy available on the receiving node, and lastly the energy required to reach the destination node. HEER combines and expands upon the method used by SEER for route selection. Network lifetime for networks of large sizes is increased, mainly due to more efficient routing of messages. The protocol was kept computationally simple and energy efficient, thus maintaining network survivability for as long as possible.
Dissertation (MEng)--University of Pretoria, 2008.
Electrical, Electronic and Computer Engineering
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23

Yong-HuiHuang and 黃詠暉. "Design and Implement of OPC UA Aggregating Server Based on Hybrid Architecture of Node Updating." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/d56ht7.

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碩士
國立成功大學
工程科學系
107
In view of the messy in the communication protocols in the industry, many companies such as Microsoft have proposed the OPC UA protocol to try to standardize the entire industry to effectively integrate various vendors. Due to the excessive sources of data and the lack of collation and integration, the academic community and the industry have the prototype of aggregating servers. To solve the problem of excessive network load caused by traditional passive updating node, the method is proposed to combine passive updating and OPC UA Pub/Sub which is the newest standard proposed by OPC foundation for actively updating the node. With the help of network bandwidth monitoring which is part of signaling server, this method can not only solve the problem of excessive repetition or excessive traffic caused by the user accessing the aggregation server too frequently but avoid network congestion caused by too frequent source OPC UA server node updates when use Pub/Sub to update node.
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24

Pretorius, Jacques Nicolaas. "Mobile tolerant hybrid network routing protocol for wireless sensor networks." Diss., 2010. http://hdl.handle.net/2263/27509.

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Wireless Sensor Networks (WSN) may consist of hundreds or even thousands of nodes and could be used for a multitude of applications such as warfare intelligence or to monitor the environment. A typical WSN node has a limited and usually irreplaceable power source and the efficient use of the available power is of utmost importance to ensure maximum lifetime of each WSN application. Each of the nodes needs to transmit and communicate sensed data to an aggregation point for use by higher layer systems. Data and message transmission among nodes collectively consume the largest amount of the energy available in a WSN. The network routing protocols ensure that every message reaches the destination and has a direct impact on the amount of transmissions to deliver a messages successfully. To this end the transmission protocol within the WSN should be scalable, adaptable and optimized to consume the least possible amount of energy to suite different network architectures and application domains. This dissertation proposes a Mobile Tolerant Hybrid Energy Efficient Routing Protocol (MT-HEER), where hybrid refers to the inclusion of both flat and hierarchical routing architectures as proposed by Page in the Hybrid Energy Efficient Routing Protocol (HEER). HEER was previously developed at the University of Pretoria and forms the starting point of this research. The inclusion of mobile nodes in the WSN deployment proves to be detrimental to protocol performance in terms of energy efficiency and message delivery. This negative impact is attributable to assuming that all nodes in the network are statically located. In an attempt to adapt to topological changes caused by mobile nodes, too much energy could be consumed by following traditional network failure algorithms. MT-HEER introduces a mechanism to pro-actively track and utilise mobile nodes as part of the routing strategy. The protocol is designed with the following in mind: computational simplicity, reliability of message delivery, energy efficiency and most importantly mobility awareness. Messages are propagated through the network along a single path while performing data aggregation along the same route. MT-HEER relies on at least 40% of the nodes in the network being static to perform dynamic route maintenance in an effort to mitigate the risks of topological changes due to mobile nodes. Simulation results have shown that MT-HEER performs as expected by preserving energy within acceptable limits, while considering the additional energy overhead introduced by dynamic route maintenance. Mobile node tolerance is evident in the protocol's ability to provide a constant successful message delivery ratio at the sink node with the introduction and increase in the number of mobile nodes. MT-HEER succeeds in providing tolerance to mobile nodes within a WSN while operating within acceptable energy conservation limits. AFRIKAANS : Koordlose Sensor Netwerke mag bestaan uit honderde of selfs duisende nodes en kan gebruik word vir 'n legio van toepassings soos oorlogs intellegensie of om die omgewing te monitor. 'n Tipiese node in so 'n netwerk het 'n beperkte en soms onvervangbare energie bron. Die effektiewe gebruik van die beskikbare energie is dus van uiterste belang om te verseker dat die maksimum leeftyd vir 'n koordlose sensor network behaal kan word. Elkeen van die nodes in the network moet die waargeneemde data aanstuur oor die netwerk na 'n versamelings punt vir latere gebruik deur applikasie vlak stelsels. Informasie en boodskap transmissie tussen die nodes is wel een van die aktiwiteite wat die meeste energie verbruik in the netwerk. Die roeterings protokol verseker dat die boodskappe die eindbestemming behaal en het 'n direkte impak op die hoeveelheid transmissies wat kan plaas vind om dit te bewerkstellig. Die roeterings protokol moet dus skaleerbaar, aanpasbaar en verfyn word om die minste moontlike energie te verbruik in verskillende toepassings velde. Hierdie verhandeling stel 'n Bewegings Tolerante Hybriede Netwerk Roeterings Protokol vir Koordlose Sensor Netwerke (“MT-HEER”) voor. In hierdie konteks verwys hybried na die samesmelting van beide plat en hierargiese roeterings beginsels soos voor gestel deur Page in Hybriede Netwerk Roeterings Protokol (“HEER”). HEER was ontwikkel by die Universiteit van Pretoria en vorm die begin punt van hierdie navorsing. Die insluiting van bewegende nodes in 'n Koordlose Sensor Netwerk toon 'n negatiewe tendens in terme van energie effektiwiteit en suksesvolle boodskap aflewerings by die eindbestemming. Die grootste rede vir hierdie negatiewe tendens is die aanname deur gepubliseerde werke dat alle nodes in die netwerk staties is. Te veel energie sal vermors word indien tradisionele fout korregerende meganismes gevolg word om aan te pas by die bewegende nodes. MT-HEER stel 'n meganisme voor om die bewegende nodes te gebruik as deel van die roetering strategie en gevolglik ook hierdie nodes te volg soos hulle beweeg deur die netwerk. Die protokol is ontwikkel met die volgende doelstellings: rekenkundig eenvoudigheid, betroubare boodskap aflewering, energie effektiwiteit en bewustheid van bewegende nodes. Boodskappe word langs 'n enkele pad gestuur deur die netwerk terwyl boodskap samevoeging bewerkstellig word om die eind bestemming te bereik. MT-HEER vereis wel dat ten minste 40% van die netwerk nodes staties bly om die dienamiese roeterings instandhouding te bewerkstellig. Simulasie toetse en resultate het bewys dat MT-HEER optree soos verwag in gevalle waar daar bewegende nodes deel uit maak van die netwerk. Energie bewaring is binne verwagte parameters terwyl die addisionele energie verbruik binne rekening gebring word om te sorg vir bewegende nodes. Die protokol se toleransie teen bewegende nodes word ten toon gestel deur die vermoë van die protokol om konstant 'n hoë suksesvolle bookskap aflewerings verhouding te handhaaf. MT-HEER behaal die uitgesette doel om 'n toleransie teen bewegende nodes beskikbaar te stel, terwyl die protokol steeds funksioneer binne verwagte energie besparings limiete. Copyright
Dissertation (MEng)--University of Pretoria, 2010.
Electrical, Electronic and Computer Engineering
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25

Verma, Suraj, Prashant Pillai, and Yim Fun Hu. "Performance evaluation of alternative network architectures for sensor-satellite integrated networks." 2013. http://hdl.handle.net/10454/9745.

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No
The last decade has seen an exponential rise in the use of wireless sensor networks (WSNs) in various applications. While these have been primarily used on their own, researchers are now looking into ways of integrating these WSNs with other existing communication technologies. One such network is the satellite network which provides significant advantage in providing communication access to remote locations due to their inherent large coverage areas. Combining WSNs and satellite will enable us to perform efficient remotely monitoring in areas where terrestrial networks may not be present. However in such a scenario, the placement of sensor nodes is crucial in order to ensure efficient routing and energy-efficiency. This paper presents four network architectures for sensor-satellite hybrid networks, sensor-satellite direct communication, connections via a gateway node employing random node layout, grid-based node layout and cluster-based node layout with data aggregation. These architectures were simulated using network simulator 2 (ns-2) and then their packet loss rate, average end-to-end packet delay, and overall energy consumption were compared. The paper concludes by proposing a suitable network topology for environmental monitoring applications.
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26

Patel, Parita. "Compilation of Graph Algorithms for Hybrid, Cross-Platform and Distributed Architectures." Thesis, 2017. http://etd.iisc.ernet.in/2005/3803.

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1. Main Contributions made by the supplicant: This thesis proposes an Open Computing Language (OpenCL) framework to address the challenges of implementation of graph algorithms on parallel architectures and large scale graph processing. The proposed framework uses the front-end of the existing Falcon DSL compiler, andso, programmers enjoy conventional, imperative and shared memory programming style. The back-end of the framework generates implementations of graph algorithms in OpenCL to target single device architectures. The generated OpenCL code is portable across various platforms, e.g., CPU and GPU, and also vendors, e.g., NVIDIA, Intel and AMD. The framework automatically generates code for thread management and memory management for the devices. It hides all the lower level programming details from the programmers. A few optimizations are applied to reduce the execution time. The large graph processing challenge is tackled through graph partitioning over multiple devices of a single node and multiple nodes of a distributed cluster. The programmer codes a graph algorithm in Falcon assuming that the graph fits into single machine memory and the framework handles graph partitioning without any intervention by the programmer. The framework analyses the Abstract Syntax Tree (AST) generated by Falcon to find all the necessary information about communication and synchronization. It automatically generates code for message passing to hide the complexity of programming in a distributed environment. The framework also applies a set of optimizations to minimize the communication latency. The thesis reports results of several experiments conducted on widely used graph algorithms: single source shortest path, pagerank and minimum spanning tree to name a few. Experimental evaluations show that the reported results are comparable to the state-of-art non-portable graph DSLs and frameworks on a single node. Experiments in a distributed environment to show the scalability and efficiency of the framework are also described. 2. Summary of the Referees' Written Comments: Extracts from the referees' reports are provided below. A copy of the written replies to the clarifications sought by the external examiner is appended to this report. Referee 1: This thesis extends the Falcon framework with OpenCL for parallel graph processing on multi-device and multi-node architectures. The thesis makes important contributions. Processing large graphs in short time is very important, and making use of multiple nodes and devices is perhaps the only way to achieve this. Towards this, the thesis makes good contributions for easy programming, compiler transformations and efficient runtime systems. One of the commendable aspects of the thesis that it demonstrates with graphs that cannot be accommodated In the memory of a single device. The thesis is generally written well. The related work coverage is very good. The magnitude of thesis excellent for a Masters work. The experimental setup is very comprehensive with good set of graphs, good experimental comparisons with state-of-art works and good platforms. Particularly. the demonstration with a GPU cluster with multiple GPU nodes (Chapter 5) is excellent. The attempt to demonstrate scalability with 2, 4 and 8 nodes is also noteworthy. However, the contributions on optimizations are weak. Most of the optimizations and compiler transformations are straight-forward. There should be summary observations on the results in Chapter 3, especially given that the results are mixed and don't quite clearly convey the clear advantages of their work. The same is the case with multi-device results in chapter 4, where the results are once again mixed. Similarly, the speedups and scalability achieved with multiple nodes are not great. The problem size justification in the multi-node results is not clear. (Referee 1 also indicates a couple of minor changes to the thesis). Referee 2: The thesis uses the OpenCL framework to address the problem of programming graph algorithms on distributed systems. The use of OpenCL ensures that the generated code is platform-agnoistic and vendor-agnoistic. Sufficient experimentation with large scale graphs and reasonable size clusters have been conducted to demonstrate the scalability and portability of the code generated by the framework. The automatically generated code is almost as efficient as manually written code. The thesis is well written and is of high quality. The related work section is well organized and displays a good knowledge of the subject matter under consideration. The author has made important contributions to a good publication as well. 3. An Account of the Open Oral Examination: The oral examination of Ms. Parita Patel took place during 10 AM and 11AM on 27th November 2017, in the Seminar Hall of the Department of Computer Science and Automation. The members of the Oral Examination Board present were, Prof. Sathish Vadhiyar, external examiner and Prof. Y. N. Srikant, research supervisor. The candidate presented the work in an open defense seminar highlighting the problem domain, the methodology used, the investigations carried out by her, and the resulting contributions documented in the thesis before an audience consisting of the examiners, some faculty members, and students. Some of the questions posed by the examiners and the members of the audience during the oral examination are listed below. 1. How much is the overlap between Falcon work and this thesis? Response: We have used the Falcon front end in our work. Further, the existing Falcon compiler was useful to us to test our own implementation of algorithms in Falcon. 2. Why are speedup and scalability not very high with multiple nodes? Response: For the multi-node architecture, we were not able to achieve linear scalability because, with the increase in number of nodes, communication cost increases significantly. Unless the computation cost in the nodes is significant and is much more than the communication cost, this is bound to happen. 3. Do you have plans of making the code available for use by the community? Response: The code includes some part of Falcon implementation (front-end parsing/grammar) also. After discussion with the author of Falcon, the code can be made available to the community. 4. How can a graph that does not fit into a single device fit into a single node in the case of multiple nodes? Response: Single node machine used in the experiments of “multi-device architecture” contains multiple devices while each node used in experiments of “multi-node architecture” contains only a single device. So, the graph which does not fit into single-node-single-device memory can fit into single-node-multi-device after partitioning. 5. Is there a way to permit morph algorithms to be coded in your framework? Response: Currently, our framework does not translate morph algorithms. Supporting morph algorithms will require some kind of runtime system to manage memory on GPU since morph algorithms add and remove the vertices and edges to the graph dynamically. This can be further explored in future work. 6. Is it possible to accommodate FPGA devices in your framework? Response: Yes, we can support FPGA devices (or any other device that is compatible for OpenCL) just by specifying the device type in the command line argument. We did not work with other devices because CPU and GPU are generally used to process graph algorithms. The candidate provided satisfactory answers to all the questions posed and the clarifications sought by the audience and the examiners during the presentation. The candidate's overall performance during the open defense and the oral examination was very satisfactory to the oral examination board. 4. Certificate of Corrections and Changes: All the necessary corrections and changes suggested by the examiners have been made in the thesis and these have been verified by the members of the oral examination board. The thesis has been recommended for acceptance in its revised form. 5. Final Recommendation: In view of the recommendations of the referees and the satisfactory performance of the candidate in the oral examination, the oral examination board recommends that the thesis of Ms. ParitaPatel be accepted for the award of the M.Sc(Engg.) Degree of the Institute. Response to the comments by the external examiner on the M.Sc(Engg.) thesis “Compilation of Graph Algorithms for Hybrid, Cross-Platform, and Distributed Architectures” by Parita Patel 1. Comment: The contributions on optimizations are weak. Response: The novelty of this thesis is to make the Falcon platform agnostic, and additionally process large scale graphs on multi-devices of a single node and multi-node clusters seamlessly. Our framework performs similar to the existing frameworks, but at the same time, it targets several types of architectures which are not possible in the existing works. Advanced optimizations are beyond the scope of this thesis. 2. Comment: The translation of Falcon to OpenCL is simple. While the translation of Falcon to OpenCL was not hard, figuring out the details of the translation for multi-device and multi-node architectures was not simple. For example, design of implementations for collection, set, global variables, concurrency, etc., were non-trivial. These designs have already been explained in the appropriate places in the thesis. Further, such large software introduced its own intricacies during development. 3. Comment: Lines between Falcon work and this work are not clear. Response: Appendix-A shows the falcon implementation of all the algorithms which we used to run the experiments. We compiled these falcon implementations through our framework and subsequently ran the generated code on different types of target architectures and compared the results with other framework's generated code. These falcon programs were written by us. We have also used the front-end of the Falcon compiler and this has already been stated in the thesis (page 16). 4. Comment: There should be a summary of observations in chapter 3. Response: Summary of observations have been added to chapter 3 (pages 35-36), chapter 4 (page 46), and chapter 5 (page 51) of the thesis. 5. Comment: Speedup and scalability achieved with multiple nodes are not great. Response: For the multi-node architecture, we were not able to achieve linear scalability because, with the increase in number of nodes, communication cost increases significantly. Unless the computation cost in the nodes is significant and is much more than the communication cost, this is bound to happen. 6. Comment: It will be good to separate the related work coverage into a separate chapter. Response: The related work is coherent with the flow in chapter 1. It consists of just 4.5 pages and separating it into a separate chapter would make both (rest of) chapter 1 and the new chapter very small. Therefore, we do not recommend it. 7. Comment: The code should be made available for use by the community. Response: The code includes some part of Falcon code (front-end parsing/grammar) also. After discussion with the author of Falcon, the code can be made available to the community. 8. Comment: Page 28: Shouldn’t the else part be inside the kernel? Response: There was some missing text and a few minor changes in Figure 3.14 (page 28) which have been incorporated in the corrected thesis. 9. Comment: Figure 4.1 needs to be explained better. Response: Explanation for Figure 4.1 (pages 38-39) has been added to the thesis. 10. Comment: The problem size justification in the multi-node results is not clear. Response: Single node machine used in the experiments of “multi-device architecture” contains multiple devices while each node used in experiments of “multi-node architecture” contains only a single device. So, the graph which does not fit into single-node-single-device memory can fit into single-node-multi-device after partitioning. Name of the Candidate: Parita Patel (S.R. No. 04-04-00-10-21-14-1-11610) Degree Registered: M.Sc(Engg.) Department: Computer Science & Automation Title of the Thesis: Compilation of Graph Algorithms for Hybrid, Cross-Platform and Graph algorithms are abundantly used in various disciplines. These algorithms perform poorly due to random memory access and negligible spatial locality. In order to improve performance, parallelism exhibited by these algorithms can be exploited by leveraging modern high performance parallel computing resources. Implementing graph algorithms for these parallel architectures requires manual thread management and memory management which becomes tedious for a programmer. Large scale graphs cannot fit into the memory of a single machine. One solution is to partition the graph either on multiple devices of a single node or on multiple nodes of a distributed network. All the available frameworks for such architectures demand unconventional programming which is difficult and error prone. To address these challenges, we propose a framework for compilation of graph algorithms written in an intuitive graph domain-specific language, Falcon. The framework targets shared memory parallel architectures, computational accelerators and distributed architectures (CPU and GPU cluster). First, it analyses the abstract syntax tree (generated by Falcon) and gathers essential information. Subsequently, it generates optimized code in OpenCL for shared-memory parallel architectures and computational accelerators, and OpenCL coupled with MPI code for distributed architectures. Motivation behind generating OpenCL code is its platform-agnostic and vendor-agnostic behavior, i.e., it is portable to all kinds of devices. Our framework makes memory management, thread management, message passing, etc., transparent to the user. None of the available domain-specific languages, frameworks or parallel libraries handle portable implementations of graph algorithms. Experimental evaluations demonstrate that the generated code performs comparably to the state-of-the-art non-portable implementations and hand-tuned implementations. The results also show portability and scalability of our framework.
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27

Schenk, Franz. "An Active Domain Node Architecture for the Semantic Web." Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0006-B3B7-3.

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Portnoy, Michael. "Optimizing hybrid wireless sensor network performance using mobile nodes /." 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR51580.

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Thesis (M.Sc.)--York University, 2008. Graduate Programme in Computer Science.
Typescript. Includes bibliographical references (leaves 147-152). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR51580
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29

Hoang, Thi-Nga, and 黃氏雅. "Axillary shoot multiplication by using stalk node explants for new Phalaenopsis hybrids." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/49749048782434830999.

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碩士
國立嘉義大學
園藝學系研究所
100
This study aimed to evaluate the effects of basal medium, light quality, and cytokinins on shoot formation from stalk node explants of new Phalaenopsis hybrids bred by National Chiayi University, Chiayi, Taiwan. The effect of basal medium on shoot formation from stalk node explants of P. Chiada Spark ‘102#10’ by using Murashige and Skoog (MS) culture medium of different strength (1/4, 1/3, 1/2 and full strength) supplemented with 3 mg.L-1 6-benzylaminopurine (BA) was investigated firstly. The results showed that 1/2 MS was the best basal medium for shoot formation and it was therefore chosen for further use in this study. The effect of light quality on shoot formation from stalk node explants of P. Chiada Spark ‘102#10’ was investigated by using the Mini-E-Light system (Nano Bio Light Technology Co., Ltd., New Taipei, Taiwan) equipped with light-emitting diodes (LEDs) as light source and included with 8 types of light conditions: warm white light (WW), cold white light (CW), 9 blue light (9B), 9 red light (9R), 8 red + 1 blue light (8R1B), 7 red + 1 blue + 1 far-red light (7R1B1IR), 7 red + 1 green + 1 blue light (7R1G1B), and 3 red + 3 blue + 3 far-red light (3R3B3IR) (see details in content). After 200 days of culture, 7R1B1IR, 7R1G1B, and 9R showed the most effectiveness on the number of shoots per explant and fresh weight of culture, while 9B exhibited the lowest on both of them. The effect of cytokinins on shoot formation from stalk node explants by using 1/2 MS culture medium with thidiazuron (TDZ) added at the concentrations of 0, 0.01, 0.1, and 1.0 mg•L-1 in combination with BA at 0, 0.1, 1.0, and 10 mg•L-1 was investigated in Doritaenopsis Chiada Gloria. The highest shoot formation percentage (79.2%) with two or more shoots per explant was obtained by TDZ at 0.1 mg.L-1 with BA at 1.0 mg.L-1. The highest protocorm-like body (PLB) like structure formation (37.5 %) was obtained when medium was supplemented with 1.0 mg.L-1 TDZ alone. For shoot formation from stalk node explants of new Phalaenopsis hybrids experimented in this study, data suggest that 1/2 MS medium supplemented with 3 mg.L-1 BA under 9R single light or 7R1B1IR mixture light condition, or 1/2 MS medium supplemented with 0.1 mg.L-1 TDZ and 1.0 mg.L-1 BA under florescent lamp are the best combinations.
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30

Ali, Md Mohsin. "High Performance Fault-Tolerant Solution of PDEs using the Sparse Grid Combination Technique." Phd thesis, 2016. http://hdl.handle.net/1885/109292.

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The data volume of Partial Differential Equation (PDE) based ultra-large-scale scientific simulations is increasing at a higher rate than that of the system’s processing power. To process the increased amount of simulation data within a reasonable amount of time, the evolution of computation is expected to reach the exascale level. One of several key challenges to overcome in these exascale systems is to handle the high rate of component failure arising due to having millions of cores working together with high power consumption and clock frequencies. Studies show that even the highly tuned widely used checkpointing technique is unable to handle the failures efficiently in exascale systems. The Sparse Grid Combination Technique (SGCT) is proved to be a cost-effective method for computing high-dimensional PDE based simulations with only small loss of accuracy, which can be easily modified to provide an Algorithm-Based Fault Tolerance (ABFT) for these applications. Additionally, the recently introduced User Level Failure Mitigation (ULFM) MPI library provides the ability to detect and identify application process failures, and reconstruct the failed processes. However, there is a gap of the research how these could be integrated together to develop fault-tolerant applications, and the range of issues that may arise in the process are yet to be revealed. My thesis is that with suitable infrastructural support an integration of ULFM MPI and a modified form of the SGCT can be used to create high performance robust PDE based applications. The key contributions of my thesis are: (1) An evaluation of the effectiveness of applying the modified version of the SGCT on three existing and complex applications (including a general advection solver) to make them highly fault-tolerant. (2) An evaluation of the capabilities of ULFM MPI to recover from a single or multiple real process/node failures for a range of complex applications computed with the modified form of the SGCT. (3) A detailed experimental evaluation of the fault-tolerant work including the time and space requirements, and parallelization on the non-SGCT dimensions. (4) An analysis of the result errors with respect to the number of failures. (5) An analysis of the ABFT and recovery overheads. (6) An in-depth comparison of the fault-tolerant SGCT based ABFT with traditional checkpointing on a non-fault-tolerant SGCT based application. (7) A detailed evaluation of the infrastructural support in terms of load balancing, pure- and hybrid-MPI, process layouts, processor affinity, and so on.
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Hsieh, Hao-Chun, and 謝皓鈞. "Hybrid Path Planning for Mobile Anchor Nodes of Wireless Sensor Networks." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3j9v82.

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碩士
中華大學
資訊工程學系
105
Wireless Sensor Network by many in space, automatic distribution of a wireless communication system in which the communication between devices is a wireless communication. Wireless sensor network system architecture, first of all a large number of sensing nodes scattered in the area to be examined to collect a variety of environmental information, and then through the wireless sensor network will collect information through the wireless data receiver back to the manager or the hands of the user. Since the sensing nodes may be used in any scattered environment, each sensing node does not know the relative position of itself with other sensing nodes, and the sensing node must locate the location in the network, and the collected messages are useful to evaluate the value. Hybrid Path Planning, the virtual anchor point is used to locate the virtual coordinates. The mobile anchor node location algorithm can significantly reduce the number of anchor nodes, and then reduce the movement path of the mobile anchor nodes by path planning to reduce the network cost and Energy consumption. This paper blends SCAN and Z-curve specific path planning and changes the mechanism of the two methods to improve the shortcomings. The SCAN problem is a problem that produces a collinear node. However, the Z-curve problem is due to the way that a particular path is planned The resulting non-essential path of motion, hybrid path planning to solve the SCAN will produce collinearity problems, and hybrid path planning to reduce the Z-curve unnecessary redundant path, mixed path planning combined with SCAN will cover the entire wireless sense The advantages of the network and the rapid positioning of Z-curve. Through the specific mechanism of this paper, it is necessary to ensure that the sensing nodes of each unknown location can receive the location information and avoid the specific path planning mode so that the sensing nodes of the unknown location are not located away from the path and are not positioned.
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Wan, Ting Yang, and 楊琬婷. "Ray Tracing Dynamic Scenes by Restructuring the Bounding Volume Hierarchy with Hybrid Nodes." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/68853535699461047762.

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Tsou, Po-Chun, and 鄒博鈞. "An Efficient Hybrid Defense Architecture to Prevent Malicious Nodes in Mobile Ad hoc Networks." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/38033338680083169390.

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碩士
國立宜蘭大學
資訊工程研究所碩士班
99
With the widespread availability of mobile devices, and rapid development of wireless technologies, the number of users of Mobile Ad hoc Networks (MANETs) is increasing at a quick rate. Due to the fact that infrastructure is not needed for MANETs, it can be deployed fast and conveniently in any environment, which makes it suitable for military operations, emergent preparedness and response operations. However, due to the dynamic nature of its network topology, its infrastructure-less property and the lack of certificate authority, achieving security of data and routing in MANETs is an ongoing challenge. Common routing protocols in MANETs such as DSR, AODV, to name a few, do not implement mechanisms for detection and responses to attacks. Focusing on possible attacks by malicious nodes based on the DSR protocol, this thesis presents a mechanism (referred to as Cooperative Bait Detection Scheme (CBDS)) that can be used to effectively detect malicious nodes launching black-hole/gray-hole attacks as well as cooperative black-hole attacks. CBDS integrates the advantages of both proactive and reactive defense architectures, and implements a reverse tracing technique to help achieving the stated goal. Simulation results are given to validate the stated goal, showing that under malicious nodes attacks, CBDS outperforms the DSR, 2ACK, and BFTR protocols in terms of packet delivery ratio and routing overhead, chosen as performance metrics.
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34

Rao, Shilpa Dinkar. "Energy Harvesting Wireless Sensor Networks : Performance Evaluation And Trade-offs." Thesis, 2016. http://hdl.handle.net/2005/2671.

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Wireless sensor networks(WSNs) have a diverse set of applications such as military surveillance, health and environmental monitoring, and home automation. Sensor nodes are equipped with pre-charged batteries, which drain out when the nodes sense, process, and communicate data. Eventually, the nodes of the WSN die and the network dies. Energy harvesting(EH) is a green alternative to solve the limited lifetime problem in WSNs. EH nodes recharge their batteries by harvesting ambient energy such as solar, wind, and radio energy. However, due to the randomness in the EH process and the limited amounts of energy that can be harvested, the EH nodes are often intermittently available. Therefore, even though EH nodes live perpetually, they do not cater to the network continuously. We focus on the energy-efficient design of WSNs that incorporate EH, and investigate the new design trade-offs that arise in exploiting the potentially scarce and random energy arrivals and channel fading encountered by the network. To this end, firstly, we compare the performance of conventional, all-EH, and hybrid WSNs, which consist of both conventional and EH nodes. We then study max function computation, which aims at energy-efficient data aggregation, in EH WSNs. We first argue that the conventional performance criteria used for evaluating WSNs, which are motivated by lifetime, and for evaluating EH networks are at odds with each other and are unsuitable for evaluating hybrid WSNs. We propose two new and insightful performance criteria called the k-outage and n-transmission durations to evaluate and compare different WSNs. These criteria capture the effect of the battery energies of the nodes and the channel fading conditions on the network operations. We prove two computationally-efficient bounds for evaluating these criteria, and show their use in a cost-constrained deployment of a WSN involving EH nodes. Next, we study the estimation of maximum of sensor readings in an all-EH WSN. We analyze the mean absolute error(MAE) in estimating the maximum reading when a random subset of the EH nodes periodically transmit their readings to the fusion node. We determine the optimal transmit power and the number of scheduled nodes that minimize the MAE. We weigh the benefits of the availability of channel information at the nodes against the cost of acquiring it. The results are first developed assuming that the readings are transmitted with infinite resolution. The new trade-offs that arise when quantized readings are instead transmitted are then characterized.Our results hold for any distribution of sensor readings, and for any stationary and ergodic EH process.
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35

Costa, Henrique Miguel Aljustrel da. "Sensing humidity with multicomponent hybrid gel films and characterization of an optimized gas delivery system." Master's thesis, 2018. http://hdl.handle.net/10362/51476.

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36

Semeano, Ana Teresa Silva. "Novel gas sensors and electronic noses for optical, electrical and hybrid sensing: development, properties and applications." Master's thesis, 2013. http://hdl.handle.net/10362/19574.

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Smell is one of the most important senses of man. It is used in everyday life, influencing our behaviour. Evaluation of the quality of food and beverages or the production control in industries that require specialised personnel, are some examples of its use. The Electronic Nose mimics the human nose, through the transduction of a chemical interaction between a sensitive layer and the volatile compounds, generating a measurable signal. Conducting polymers, doped with dodecylbenzenesulfonic acid, employed in electrical gas sensors and in an electronic nose showed their applicability in monitoring the circadian emissions of fragrance by the plant Madagascar Jasmin and in the discrimination and classification of different samples of flaxseed, respectively. An innovative approach in the development of sensitive thin films based on organized liquid crystal micelles in an ionic liquid, encapsulated in a biopolymer matrix and used as sensitive layers for gas sensors, is the focus of this thesis. Liquid crystal micelles acting as sensitive elements that change reversibly their orientation in the presence of volatile compounds showed, as a proof of concept, their potential use in the classification of volatile solvents. They were also successfully tested for monitoring the quality of Tilapia fish. The combination of this optical system with the electrical system gave the so called "hybrid sensor" with dual response. Thus, a single sensor was efficient in the quantification of ethanol in gasoline. Polarized light microscopy, SEM and AFM techniques were used to study the morphology of these layers and have revealed that the formation of the micelles is closely influenced by the solvent where the liquid crystal molecules are arranged. QCM studies were conducted in order to learn more about the interaction of these films with volatile compounds, and to check the influence of parameters such as the exposure time, solvent nature, film composition and drying time, on the film. These biopolymer films were also used as immobilisation matrix for cytochrome c, forming electrochemical sensors having an additional optical response.
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37

Gawęda, Sylwia. "Nowe materiały półprzewodnikowe na bazie dwutlenku tytanu i wybranych biocząsteczek : otrzymywanie i charakterystyka fizykochemiczna." Praca doktorska, 2010. http://ruj.uj.edu.pl/xmlui/handle/item/41615.

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