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Etude de la stabilité et de la précision des modèles utilisés dans la correction des effets de proximité optique en photolithographie / Study of the impact of different physical parameters during OPC model creation for 65nm and 45nm technologiesSaied, Mazen 30 September 2011 (has links)
À l’heure actuelle, les modèles photochimiques utilisés dans la correction des effets de proximitéoptique (OPC) en photolithographie sont devenus complexes et moins physiques afin de permettre decapturer rapidement le maximum d’effets optiques et chimiques. La question de la stabilité de tels modèlespurement empiriques est devenue d’actualité. Dans ce mémoire, nous avons étudié la stabilité desmodèles photochimiques actuels en examinant les différentes causes d’instabilité vis-à-vis des paramètresdu procédé. Dans la suite, nous avons développé une méthode perturbative permettant d’évaluer le critèrede la stabilité. L’obtention de modèles simples et stables nous conduit à séparer les effets optiques desautres effets chimiques. De plus, les approximations utilisées dans la modélisation des systèmes optiquesopérant à grande ouverture numérique entraînent des erreurs résiduelles pouvant dégrader la précisionet la stabilité des modèles OPC. Ainsi, nous nous sommes intéressés à étudier les limites de validitéde l’approximation de Kirchhoff, méthode qui, jusqu’à présent, est la plus utilisée dans la modélisationdu champ proche d’un masque. D’autres méthodes semi-rigoureuses, permettant de modéliser les effetstopographiques, ont été également évaluées. Ces méthodes approchées permettent de gagner en précisionmais dégradent le temps de calcul. Nous avons ainsi proposé différentes façons de corriger les effetstopographiques du masque, tout en gardant l’approximation de Kirchhoff dans la modélisation de la partieoptique. Parmi les méthodes proposées, nous exploitons celle permettant de réduire les erreurs liéesaux effets topographiques du masque par l’intermédiaire d’un second modèle empirique. Nous montronsque pour garantir une précision adéquate, il est nécessaire d’augmenter la complexité du modèle en rajoutantdes termes additionnels. Enfin, pour garantir la stabilité numérique du modèle empirique, nousintroduirons une nouvelle méthode approchée hybride rapide et précise, la méthode des multi-niveaux,permettant d’inclure les effets topographiques par décomposition multi-niveaux du masque fin et discuteronsses avantages et ses limites. / At present, common resist models utilized in photolithography to correct for optical proximity effects(OPC) became complex and less physical in order to capture the maximum of optical and chemical effectsin shorter times. The question on the stability of such models, purely empirical, become topical. In thisthesis, we study the stability of existing OPC models by examining the origins of model instability towardsprocess parameters. Thus, we have developed a perturbative method in order to evaluate the stabilitycriterion. However, achieving stable and simple models needs a separation between optical and otherchemical effects. Besides, multiple approximations, widely utilized in the modeling of optical systemsoperating at high numerical aperture, lead to residual errors which can degrade OPC model accuracyand stability. Thus, we were interested to study the limits of validity of the Kirchhoff approximation,a method which, so far, is the most commonly used in mask near-field modeling. Other semi-rigorousmethods for mask topography effect modeling were also evaluated. These approximate methods canimprove the accuracy but degrades the run time. We then suggested different techniques to correct formask topography effects, while keeping the Kirchhoff approximation in the modeling of the optical part.Among them, we showed that errors due to mask topography effects can be partially captured by asecond empirical model. However, in order to ensure a good accuracy, it is necessary to increase themodel complexity by using more additional empirical terms. Finally, in order to achieve a numericalstability of the empirical model, we introduced a new hybrid fast and accurate method, the multi-levelmethod, which allows us to correct for mask topography effects through a multi-level decomposition ofthe thin mask and discussed its advantages and drawbacks.
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Security Analysis of OPC UA in Automation Systems for IIoT / Säkerhetsanalys av OPC UA inom automationssystem för IIoT.Varadarajan, Vaishnavi January 2022 (has links)
Establishing secured communication among the different entities in an industrial environment is a major concern. Especially with the introduction of the Industrial Internet of Things (IIoT), industries have been susceptible to cyber threats, which makes security a critical requirement for the industries. Prevailing industrial communication standards were proven to meet the security needs to some extent, but the major issue which was yet to be addressed was interoperability. To achieve interoperability, Open Platform Communication Unified Architecture (OPC UA) was introduced as a communication protocol. OPC UA helped bridge the gap between Information Technology (IT) and Operational Technology (OT) security needs, but this also gives rise to new attack opportunities for the intruder. In this thesis, we have analysed the security challenges in OPC UA and the impact of two different cyberattacks on the OPC UA. First, we have implemented an OPC UA Network with the help of Raspberry Pis and open62541, an open-source implementation of the OPC UA client and server. Following this, to evaluate the performance of the network, we performed three cybersecurity attacks, Packet Sniffing, Man in the Middle Attack (MITM) and Denial of Service attack. We assessed the impact these attacks have on the OPC UA network. We have also discussed the detection mechanism for the same attacks. This analysis has helped us recognize the threats faced by OPC UA in an IIoT environment with respect to message flooding, packet sniffing and man in the middle attack and the countermeasures to this attack have been discussed / Att etablera en säker kommunikation mellan de olika enheterna i en industriell miljö är en stor utmaning. Speciellt efter introduktionen av Industrial Internet of Things (IIoT) har industrier varit mottagliga för cyberhot vilket gör cybersäkerhet en prioritet. Rådande industriella kommunikationsstandarder har visats att till viss del uppfylla säkerhets- behoven, men en av de största problemen var bristen på interoperabilitet. För att uppnå interoperabiliteten skapades Open Platform Communication Unified Architecture (OPC UA) som kommun- ikationsprotokoll. OPC UA hjälper till att överbrygga gapet mellan säkerhetsbehoven av information- steknologi (IT) och Operational Technology (OT), men detta ger också upphov till nya attackmöjligheter för inkräktare. I detta examensarbete har vi analyserat säkerhetsutmaningarna i OPC UA och effekten av två olika cyberattacker på OPC UA. Först har vi implementerat ett OPC UA Network med hjälp av Raspberry Pis och open62541 som är en öppen källkodsimplementering av OPC UA klient och server. Efter detta utförde vi tre cybersäkerhetsattacker för att utvärdera nätverkets prestanda, packet sniffing, Man in the Middle Attack (MITM) och Denial of Service attack. Vi bedömde vilken effekt dessa attacker har på OPC UA-nätverket. Vi har också diskuterat detektionsmekanismen för samma attacker. Denna analys har hjälpt oss att känna igen de hot som OPC UA står inför i en IIoT-miljö med avseende på dataflöde, packet sniffing och Man in the Middle attack och även försvar mot dessa attacker har diskuterats.
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Security Analysis of OPC UA in Automation Systems for IIoT / Säkerhetsanalys av OPC UA inom automationssystem för IIoT.Varadarajan, Vaishnavi January 2022 (has links)
Establishing secured communication among the different entities in an industrial environment is a major concern. Especially with the introduction of the Industrial Internet of Things (IIoT), industries have been susceptible to cyber threats, which makes security a critical requirement for the industries. Prevailing industrial communication standards were proven to meet the security needs to some extent, but the major issue which was yet to be addressed was interoperability. To achieve interoperability, Open Platform Communication Unified Architecture (OPC UA) was introduced as a communication protocol. OPC UA helped bridge the gap between Information Technology (IT) and Operational Technology (OT) security needs, but this also gives rise to new attack opportunities for the intruder. In this thesis, we have analysed the security challenges in OPC UA and the impact of two different cyberattacks on the OPCUA. First, we have implemented an OPC UA Network with the help of Raspberry Pis and open62541, an open-source implementation of the OPC UA client and server. Following this, to evaluate the performance of the network, we performed three cybersecurity attacks, Packet Sniffing, Man in the Middle Attack (MITM) and Denial of Service attack. We assessed the impact these attacks have on the OPC UA network. We have also discussed the detection mechanism for the same attacks. This analysis has helped us recognize the threats faced by OPC UA in an IIoT environment with respect to message flooding, packet sniffing and man in the middle attack and the countermeasures to this attack have been discussed. / Att etablera en säker kommunikation mellan de olika enheterna i en industriell miljö är en stor utmaning. Speciellt efter introduktionen av Industrial Internet of Things (IIoT) har industrier varit mottagliga för cyberhot vilket gör cybersäkerhet en prioritet. Rådande industriella kommunikationsstandarder har visats att till viss del uppfylla säkerhets- behoven, men en av de största problemen var bristen på interoperabilitet. För att uppnå interoperabiliteten skapades Open Platform Communication Unified Architecture (OPC UA) som kommun- ikationsprotokoll. OPC UA hjälper till att överbrygga gapet mellan säkerhetsbehoven av information- steknologi (IT) och Operational Technology (OT), men detta ger också upphov till nya attackmöjligheter för inkräktare. I detta examensarbete har vi analyserat säkerhetsutmaningarna i OPC UA och effekten av två olika cyberattacker på OPC UA. Först har vi implementerat ett OPC UA Network med hjälp av Raspberry Pis och open62541 som är en öppen källkodsimplementering av OPC UA klient och server. Efter detta utförde vi tre cybersäkerhetsattacker för att utvärdera nätverkets prestanda, packet sniffing, Man in the Middle Attack (MITM) och Denial of Service attack. Vi bedömde vilken effekt dessa attacker har på OPC UA-nätverket. Vi har också diskuterat detektionsmekanismen för samma attacker. Denna analys har hjälpt oss att känna igen de hot som OPC UA står inför i en IIoT-miljö med avseende på dataflöde, packet sniffing och Man in the Middle attack och även försvar mot dessa attacker har diskuterats.
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E-procurement adoption, its benefits and costsMahdillou, Hossein, Akbary, Jawid January 2014 (has links)
This thesis report aims at illustrating and describing how e-procurement can contribute in creating value and reducing overheads associated with the procurement process through adopting and implementing e-procurement systems and applications in the supply chain network of an organization. It is an obvious fact that e-procurement plays a vital role in managing the supply chain especially now that outsourcing has become very common in the business market environment around the world. The main purpose of our bachelor thesis work is to find out how e-procurement can contribute in creating value, reducing cost and gaining more profit out of the procurement process. Since this thesis report is meant to cover the available literature on procurement and e-procurement only limited areas of the supply chain management is presented.When it comes to methodologies, available literatures on procurement and e-procurement have been covered to extract the most plausible information and data related how e-procurement contributes in creating value and reducing costs and overheads in the supply chain management. First a framework of modern procurement processes and stages is given as a basis and then e-procurement is treated being the technologies and key factors in implementation of e-procurement.This thesis work tries to consolidate prevalent ideas as well as facts that have been tested by means of academic researches carried out by scholars of the field and interdisciplinary of industrial engineering. / Program: BSc in Industrial Engineering - International Business Engineering
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Optique pour la Microélectronique : du capteur au traitement de l'imageFossati, Caroline 26 November 2008 (has links) (PDF)
Il s'agit ici du bilan de plus de 10 ans d'enseignement et de recherche dans le domaine de la micro et de l'opto électronique, et plus particulièrement des dernières années passées au sein de l'Ecole Centrale Marseille et de l'institut Fresnel. <br />Deux thématiques de recherche sont abordées : <br />- La caractérisation optique de défauts submicroniques dans les matériaux, qui a constitué, dans la continuité de ma thèse, la première partie de mes activités : caractérisation de précipités dans le Silicium par le développement d'un microscope infrarouge à balayage ; développement d'un microscope photo thermique pour la détection de nano défauts absorbants précurseurs d'endommagement dans les couches minces optique.<br />- L'optique pour la microélectronique, thématique initiée en 2000 au laboratoire, qui aborde la modélisation optique de capteurs d'images en technologie CMOS en vue d'adapter leur structure aux contraintes de réflexion et diffraction optique liées à la réduction de taille des pixels imposée par le marché.<br />Sont aussi concernés les masques avancés pour la photolithographie optique, et l'adaptation de techniques de traitement du signal et des images à la modélisation de corrections optiques de proximité (OPC) qu'il faut appliquer sur les masques pour corriger les effets de la diffraction dans le cadre de la diminution de taille des composants.<br />Des projets de recherche orientés sur l'application des capteurs et du traitement multidimensionnel du signal pour des applications médicales et de sécurité sont aussi présentés.
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Chemistry and Corrosion Mechanisms of Steels Embedded in High-density Slag Concrete for Storage of Used Nuclear FuelNadarajah, Parthiban 15 December 2011 (has links)
The chemistry and corrosion mechanisms associated with reduced sulfur compounds such as calcium sulfide, present in ground granulated blast-furnace slag (GGBFS), have been studied in high-density concrete, mortar and simulated pore-water environments. The high-density concrete and mortar samples were produced to replicate the high-density GGBFS concrete, in the dry storage containers (DSCs), used for radiation shielding from used nuclear fuel. Electrochemical measurements on embedded steel electrodes in high-density GGBFS concrete and mortar samples, showed that sulfide is capable of consuming oxygen to create a stable, reducing environment, though not in all cases, and the high-frequency electrolyte resistance increases with hydration time. Ion chromatography on simulated pore-water environments determined that thiosulfate is quite kinetically stable as a sulfide oxidation product and magnetite is capable of oxidizing sulfide. Microscopy has also been used to provide visual evidence of GGBFS hydration and elemental quantification of the hydrating microstructure in different environments.
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Chemistry and Corrosion Mechanisms of Steels Embedded in High-density Slag Concrete for Storage of Used Nuclear FuelNadarajah, Parthiban 15 December 2011 (has links)
The chemistry and corrosion mechanisms associated with reduced sulfur compounds such as calcium sulfide, present in ground granulated blast-furnace slag (GGBFS), have been studied in high-density concrete, mortar and simulated pore-water environments. The high-density concrete and mortar samples were produced to replicate the high-density GGBFS concrete, in the dry storage containers (DSCs), used for radiation shielding from used nuclear fuel. Electrochemical measurements on embedded steel electrodes in high-density GGBFS concrete and mortar samples, showed that sulfide is capable of consuming oxygen to create a stable, reducing environment, though not in all cases, and the high-frequency electrolyte resistance increases with hydration time. Ion chromatography on simulated pore-water environments determined that thiosulfate is quite kinetically stable as a sulfide oxidation product and magnetite is capable of oxidizing sulfide. Microscopy has also been used to provide visual evidence of GGBFS hydration and elemental quantification of the hydrating microstructure in different environments.
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Etude de la stabilité et de la précision des modèles utilisés dans la correction des effets de proximité optique en photolithographieSaied, Mazen 30 September 2011 (has links) (PDF)
À l'heure actuelle, les modèles photochimiques utilisés dans la correction des effets de proximitéoptique (OPC) en photolithographie sont devenus complexes et moins physiques afin de permettre decapturer rapidement le maximum d'effets optiques et chimiques. La question de la stabilité de tels modèlespurement empiriques est devenue d'actualité. Dans ce mémoire, nous avons étudié la stabilité desmodèles photochimiques actuels en examinant les différentes causes d'instabilité vis-à-vis des paramètresdu procédé. Dans la suite, nous avons développé une méthode perturbative permettant d'évaluer le critèrede la stabilité. L'obtention de modèles simples et stables nous conduit à séparer les effets optiques desautres effets chimiques. De plus, les approximations utilisées dans la modélisation des systèmes optiquesopérant à grande ouverture numérique entraînent des erreurs résiduelles pouvant dégrader la précisionet la stabilité des modèles OPC. Ainsi, nous nous sommes intéressés à étudier les limites de validitéde l'approximation de Kirchhoff, méthode qui, jusqu'à présent, est la plus utilisée dans la modélisationdu champ proche d'un masque. D'autres méthodes semi-rigoureuses, permettant de modéliser les effetstopographiques, ont été également évaluées. Ces méthodes approchées permettent de gagner en précisionmais dégradent le temps de calcul. Nous avons ainsi proposé différentes façons de corriger les effetstopographiques du masque, tout en gardant l'approximation de Kirchhoff dans la modélisation de la partieoptique. Parmi les méthodes proposées, nous exploitons celle permettant de réduire les erreurs liéesaux effets topographiques du masque par l'intermédiaire d'un second modèle empirique. Nous montronsque pour garantir une précision adéquate, il est nécessaire d'augmenter la complexité du modèle en rajoutantdes termes additionnels. Enfin, pour garantir la stabilité numérique du modèle empirique, nousintroduirons une nouvelle méthode approchée hybride rapide et précise, la méthode des multi-niveaux,permettant d'inclure les effets topographiques par décomposition multi-niveaux du masque fin et discuteronsses avantages et ses limites.
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Desenvolvimento de um sistema misto de pasta ? base de geopol?mero e cimento portland para corre??o de perda de circula??oBarros, Marcus Vinicius Cavalcanti 18 February 2013 (has links)
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Previous issue date: 2013-02-18 / The materials engineering includes processes and products involving several areas of
engineering, allowing them to prepare materials that fulfill the needs of various new products.
In this case, this work aims to study a system composed of cement paste and geopolymers,
which can contribute to solving an engineering problem that directly involves the exploitation
of oil wells subject to loss of circulation. To correct it, has been already proposed the use of
granular materials, fibers, reducing the drilling fluid or cement paste density and even surface
and downhole mixed systems. In this work, we proposed the development of a slurry mixed
system, the first was a cement-based slurry and the second a geopolymer-based slurry. The
cement-based slurry was formulated with low density and extenders, 12.0 ppg (1.438 g/cm ?),
showing great thixotropic characteristics. It was added nano silica at concentrations of 0.5, 1.0
and 1.5 gps (66.88, 133.76 and 200.64 L/m3) and CaCl2 at concentrations of 0.5, 1, 0 and
1.5%. The second system is a geopolymer-based paste formulated from molar ratios of 3.5
(nSiO2/nAl2O3), 0.27 (nK2O/nSiO2), 1.07 (nK2O/nAl2O3) and 13.99 (nH2O/nK2O). Finally,
we performed a mixture of these two systems, for their application for correction of
circulation lost. To characterize the raw materials, XRD, XRF, FTIR analysis and titration
were performed. The both systems were characterized in tests based on API RP10B.
Compressive strength tests were conducted after curing for 24 hours, 7 and 28 days at 58 ?C
on the cement-based system and the geopolymer-based system. From the mixtures have been
performed mixability tests and micro structural characterizations (XRD, SEM and TG). The
results showed that the nano silica, when combined with CaCl2 modified the rheological
properties of the cement slurry and from the concentration of 1.5 gpc (200.64 L / m?) it was
possible to obtain stable systems. The system mixture caused a change in the microstructure
of the material by favoring the rate of geopolymer formation to hinder the C3S phase
hydration, thus, the production of CSH phases and Portlandite were harmed. Through the mixability tests it can be concluded that the system, due to reduced setting time of the
mixture, can be applied to plug lost circulation zones when mixed downhole / A engenharia de materiais abrange processos e produtos envolvendo v?rias ?reas da
engenharia, permitindo que sejam preparados materiais que atendam a v?rias necessidades de
novos produtos. Neste caso, este trabalho tem por objetivo estudar um sistema de pasta
composto por cimento e geopol?meros, que possa contribuir para a resolu??o de um problema
de engenharia que envolve diretamente a explora??o de po?os de petr?leo sujeitos ? perda de
circula??o. Para corrigi-la, j? foi proposto na literatura o uso de materiais granulares, fibrosos,
redu??o da densidade do fluido de perfura??o ou pasta de cimento e at? mesmo sistemas
mistos de fluidos misturados na superf?cie ou no fundo do po?o. Neste trabalho, foi proposto
o desenvolvimento de um sistema misto de pastas, sendo o primeiro ? base de cimento
Portland e o segundo ? base de geopol?mero. A pasta ? base de cimento, foi formulada com
baixa massa espec?fica e aditivos extendedores, 12,0 lb/gal (1,438 g/cm?), apresentando
grande car?ter tixotr?pico. Essa pasta foi aditivada com nanoss?lica, em concentra??es de 0,5;
1,0 e 1,5 gpc (66,88; 133,76 e 200,64 L/m3) e CaCl2, em concentra??es de 0,5; 1,0 e 1,5 %. A
segunda pasta se constitui ? base de geopol?mero, sendo formulada a partir das raz?es molares
de 3,5 (nSiO2/nAl2O3); 0,27 (nK2O/nSiO2); 1,07 (nK2O/nAl2O3) e 13,99 (nH2O/nK2O). E por
fim, foi realizada a mistura desses dois sistemas, visando sua aplica??o para corre??o de perda
de circula??o. Para caracterizar os precursores foram utilizadas as t?cnicas de DRX, FRX,
FTIR e titula??o. Foram realizados os ensaios de caracteriza??o baseados na API RP10B para
ambas as pastas puras. Ensaios de resist?ncia ? compress?o foram realizados ap?s a cura por
24 horas, 7 e 28 dias ? 58 ?C, para os sistemas de pasta de cimento e geopol?mero,
separadamente. A partir das misturas, foi realizado o ensaio de misturabilidade e
caracteriza??es microestruturais (DRX, TG e MEV). Os resultados mostraram que a
nanoss?lica, quando combinada ao CaCl2 modificou as propriedades reol?gicas da pasta de
cimento e a partir da concentra??o de 1,5 gpc (200,64 L/m?) foi poss?vel se obter sistemas
est?veis. A mistura dos sistemas ocasionou uma modifica??o da microestrutura do material, atrav?s do favorecimento da rea??o de geopolimeriza??o em detrimento da hidrata??o da fase
C3S, com isso, a produ??o das fases Portlandita e C-S-H foram prejudicadas. Atrav?s dos
ensaios de misturabilidade, devido ao reduzido tempo de pega das misturas, pode-se concluir
que o sistema misturado, pode ser aplicado para tamponar zonas de perda de circula??o
quando misturado no fundo do po?o
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Economía digital, sitios web y PYMES del sector artesanía en el Perú / Digital economy, Websites and SMEs of the handicraft industry in PeruDuarte Cueva, Franklin 10 April 2018 (has links)
The companies are operating in complex, dynamic and uncertain environments that it difficult to compete. The e-economy each time has a major presence in business world, then, the small entrepreneurs must design strategies based on Information and Communication Technologies (ICTs), particularly the use of Internet, to improve company performance. Thus, the efficient implementation of websites is a mechanism that should exploit exporting small and medium-sized enterprises (SMEs) or with export potential, of the handicrafts industry, to communicate desired company image and optimize customer service, this it has implications who require to be analyzed to make an effective use of the ICTs. / Las empresas actualmente se desenvuelven en entornos complejos, dinámicos e inciertos que hacen difícil competir. Ya que la economía digital cada vez tiene mayor presencia en el mundo de los negocios, entonces, los pequeños empresarios deben diseñar estrategias basadas en las tecnologías de la información y la comunicación (TIC), particularmente el uso de Internet, para mejorar el desempeño de la empresa. Así, la implementación de sitios web eficientes es un mecanismo que deben explotar las PYMES exportadoras o con potencial exportador del sector artesanías para comunicar la imagen deseada de la empresa y optimizar así la atención al cliente; esto tiene implicancias que requieren ser analizadas para hacer un uso eficaz de las TIC.
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