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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Numerical studies on electromagnetic compatibility problems in substation environments

Pereira, Elisete Ternes January 1993 (has links)
No description available.
2

Investigating the function of Ysy6p and the EMC complex

Robertson, Henry January 2013 (has links)
During or following mRNA translation by cytosolic ribosomes the nascent protein being synthesised can be targeted to the endoplasmic reticulum (ER). This targeting of nascent proteins leads to either their transport across the ER or in the case of transmembrane proteins their integration into the ER membrane. This process is carried out by the Sec61 complex which is conserved across organisms including bacteria, yeast and mammals. The ER is a site of protein folding, modification, forward transport and quality control. Misfolded proteins can be directed to the ER associated degradation pathway which mediates retrotranslocation of proteins out of the ER and degradation by the proteasome. A lot is already known about ER associated processes, however, the function of many factors associated with the ER are still poorly understood. Two examples of such factors in yeast include Ysy6p and the ER membrane complex (EMC). The mammalian homolog of Ysy6p, RAMP4 has been shown to be recruited to ribosomes during the integration of transmembrane proteins into the ER and implicated in processes such as protein degradation. The function of the EMC is unknown but has been suggested to function in either protein folding, forward trafficking from the ER or ERAD.Here it has been shown that deletion of EMC1, EMC2, EMC3, EMC6 but not EMC4 or EMC5 causes defects in growth at 39.5°C or on media containing SDS. Defective growth on media containing SDS is suggestive of defects in cell wall or membrane biogenesis and both SDS and elevated temperature are known to cause the induction of the unfolded protein response. This suggests that certain members of the EMC complex are involved in stress responses or secretory processes. Functional investigation of ER associated pathways showed that a ∆emc5 strain has a defect in clearance of the ERAD-M substrate Hmg2-6myc however ∆emc1 does not. The ERAD and competitive growth phenotypes are therefore unlinked and suggests that the EMC complex has a function in multiple pathways which are independently affected by deletion of individual members of the complex. To test whether Ysy6p was a functional yeast homolog of RAMP4, processes previously observed to be involved with the function of RAMP4 were investigated. Strikingly, it has been demonstrated that Ysy6p, similarly to RAMP4, is a protein which tightly associates with ribosomes. In addition, RAMP4 has been previously observed to affect protein degradation whereas here it has been shown that deletion of YSY6 causes an alteration in the degradation profile of Hmg2-6myc. The findings are therefore consistent with the notion that Ysy6p and RAMP4 are functional homologs. In order to further characterise the molecular basis for ribosome association N terminal truncations of opsin tagged Ysy6p were made. It was demonstrated that partial deletion of a conserved cytosolic domain predicted to form a helix-turn-helix resulted in a near loss of cosedimentation of Ysy6p with ribosomes. Furthermore, it was shown that Ysy6p crosslinks with MBS to three factors of 22 kDa, 18 kDa and 10 kDa the identities of which remain undetermined. The data therefore suggest that Ysy6p is involved in processes associated with co-translational integration of proteins and ERAD. In addition, the data also suggest that the EMC complex is involved in ERAD and stress responses.
3

Design av modell för uppföljning av elektromagnetisk kompatibilitet för nya komponenter som ska installeras ombord på flygplan utrustade med Wi-Fi/Telefoni / Design of model to follow up electromagnetic compatibility of new components to be installed on WiFi/Telephony equipped aircraft

Sundberg, Liza January 2015 (has links)
SAS is the leading airline in Scandinavia, and with the keywords comfort, safety and punctuality they look to provide their customers with an easy way to travel. In order to obtain this they have equipped many of their aircrafts with wireless networks (WiFi). To ensure continued airworthiness a method was required for investigating the electromagnetic compatibility of new components to be installed on the aircrafts, in other words whether or not they were at risk of interference from the wireless network and the portable devices connected to it. Earlier this had been taken care of by external companies, but SAS was looking for a way to do more of the work on their own in order to both simplify the procedure and decrease costs. In this project a model was developed for classification, analysis and follow-up documentation of a component to determine its compatibility status. This was achieved by studies of several documents where recommendations and regulations were listed. The information was then clarified and gathered into more easily observable forms, according to the wishes of SAS. The result of this work was presented in three documents. The first document described the three- step procedure which determined whether or not analysis was sufficient for a component, or if TPED testing was required. In the latter scenario, testing would still be performed externally. Document number two consisted of a component record where every tested and analysed component was to be listed after the compatibility status had been determined. Finally, document number three was a new chapter of SAS CAME-P regarding EMC management. / SAS är Skandinaviens ledande flygbolag. Med fokus på de tre nyckelorden komfort, säkerhet och punktlighet önskar de erbjuda sina resenärer ett enkelt sätt att resa. I enlighet med detta har företaget utrustat många av sina flygplan med trådlöst nätverk (WiFi). För att säkerställa en fortsatt flygduglighet krävdes en metod för att undersöka den elektromagnetiska kompatibiliteten för nya komponenter som så småningom skulle kunna komma att installeras ombord på dessa WiFi-utrustade flygplan, det vill säga huruvida komponenterna kunde tänkas störas av nätverket och de trådlösa enheter som kopplas upp mot detta. Tidigare skötte flygbolaget detta helt och hållet externt, men önskade nu en lösning för att göra en större del av arbetet på egen hand och på så vis både förenkla arbetet och minska kostnaderna. I detta arbete togs en modell fram för klassificering, analys och uppföljning av en komponent för att redogöra för dess kompatibilitetsstatus. Detta åstadkoms genom studie av ett flertal dokument där rekommendationer och riktlinjer stod listade. Informationen förtydligades sedan och sammanfördes i mer lättöverskådliga former enligt SAS önskemål. Resultatet av arbetet presenterades i tre dokument. Det första dokumentet beskrev den procedur i tre steg som avgjorde om analys var tillräcklig för att ansöka om myndighetsgodkännande eller om testning fortfarande var nödvändig. Om TPED-testning skulle bli aktuell skulle denna även i fortsättningen skötas externt. Dokument nummer två bestod av ett komponentregister där alla testade och analyserade komponenter skulle föras in när kompatibilitetsstatusen blivit känd. Det tredje och sista dokumentet var ett nytt kapitel till SAS CAME-P rörande EMC-hantering.
4

En undersökning av Elektromagnetiska störningar på hörselmätningsutrustning

Wetterblad, Victor, Friman, Manne January 2009 (has links)
No description available.
5

EMC-problem på kretskort : design, konstruktion och dokumentation av kretskort med avseende på EMC-egenskaper

Lundberg, Johan January 2002 (has links)
No description available.
6

EMC-problem på kretskort : design, konstruktion och dokumentation av kretskort med avseende på EMC-egenskaper

Lundberg, Johan January 2002 (has links)
No description available.
7

The electromagnetic fields from a two-wire transmission line

Culligan, Allan James January 1997 (has links)
No description available.
8

Electromagnetic Compatibility (EMC) test in an Open Area

Samira, Nair January 2023 (has links)
Electromagnetic compatibility (EMC) is a very important and increasingly relevant technology in use and is closely related to many technologies such as automobiles and aerospace industry technology including aircraft and spacecraft. Achieving electromagnetic compatibility between equipment inside the device is more than necessary to avoid the problem of interference leading to serious problems. More than that, achieving electromagnetic compatibility for the device as a complete system is quite challenging. The device as a whole system is necessary to be compatible with its electromagnetic environment in order to avoid the problem of interference with other devices which also leads to safety issues. The objective of the thesis is to measure EMC radiated emission from the aircraft as a complete system and to know its compatibility with its electromagnetic environment, by building knowledge of the challenges that arise when conducting electromagnetic compatibility measurements of the aircraft as a whole system outside a protected environment. The challenge here is that there are no standards for EMC radiated emission of the aircraft as a complete system in an Open Area Test Site (OATS). This required us to research and try to relate what was done in this field to try to plan to build an OATS to conduct EMC radiated emission on aircraft as a whole system. We have come up with, that the measurement of EMC radiated emissions performed on the aircraft as a complete system in an OATS at Skellefteå Airport, shows similar results to those obtained on Aircraft SIMulator (ASIM) tested in a Fully Anechoic Chamber (FAC). In addition, we performed a civil airport of Skellefteå site validation measurement and obtained the result that the site complies with the OATS requirements in CISPR 16-1-4: 2019 standard. This work is considered a building block for other EMC studies in the field of space technology, which calls for the need to think about achieving electromagnetic compatibility to avoid all that results from electromagnetic interference (EMI) on the safety of pilots, astronauts, and all human life.
9

Optimisation de modèles comportementaux de composants pour la prédiction de défaillances fonctionnelles et matérielles liées aux décharges électrostatiques (ESD) / Behavioral model optimization of components for the prediction of soft and hard failures caused by electrostatic discharge (ESD)

Escudié, Fabien 11 December 2018 (has links)
Les événements transitoires de forte puissance (EFT - Electrical Fast Transient) sont l'une des préoccupations des concepteurs de systèmes embarqués. Ils peuvent conduire au dysfonctionnement du système et sont à l'origine d'un grand nombre de défaillances matérielles et fonctionnelles. Notre étude est principalement portée sur l'impact des décharges électrostatique (ESD - Electro Static Discharge) sur l'électronique embarquée dans un véhicule. D'après une étude de Renault, un véhicule peut subir deux décharges par jour durant sa vie. Les ingénieurs systèmes ne disposent pas de moyen pour prédire l'impact de ces décharges dans les systèmes, et les solutions actuelles sont essentiellement basées sur l'expérience. Afin de prédire le chemin d'un ESD dans tout le système électronique et la stratégie de protection à adopter pour protéger les composants les plus sensibles, des recherches dans le monde entier sont en cours. Les travaux de recherche du groupe ESE du LAAS-CNRS ont mené à des méthodologies de modélisation de composant passif, de circuit intégré et de carte électronique en VHDL-AMS. Les circuits intégrés sont dotés d'un réseau de protection ESD interne qui permet de détourner le stress des zones critiques. La méthodologie développée au cours des précédentes années permet de modéliser le comportement de ce réseau de protection. Cependant, ces modèles sont rudimentaires, ils décrivent uniquement le niveau de déclenchement de la protection et son impédance quasi-statique en fonction du niveau de stress ESD. Aucune information sur le comportement transitoire de la protection n'est décrite dans le modèle. Il est donc difficile de prévoir certaines défaillances liées aux phénomènes transitoires de déclenchement des protections faisant apparaitre de très fortes surtensions ou des niveaux de courant mal évalués. Les différents aspects abordés durant cette thèse permettent de résoudre ces problèmes en proposant des modèles dynamiques, et différentes méthodes pour pouvoir extraire les paramètres des modèles.[...] / Electrical Fast Transient (EFT) are one of the concerns of embedded system engineers. They can lead to system malfunction. EFT are the cause of a large number of hardware and software failures. Our study is mainly focused on the impact of Electro Static Discharge (ESD) on embedded electronic systems, focusing on car's applications. According to a Renault's study, a car can suffer two discharges per day during its entire life. System engineers do not have any tools to predict the ESD impact on the systems. In order to predict the ESD path throughout the electronic system and adjust the ESD protection strategy to provide proper protection for all critical components, some researches around the world are in process. The research results from ESE working group from the LAAS-CNRS laboratory, were mainly on passive components, integrated circuits and electronics boards modeling methods, implemented in VHDL-AMS language. Integrated circuits have an internal ESD protection network that helps to deflect the stress from critical areas. The methodology developed in the last few years allows to model the behavior of this protection network. However, these models are basically made, they are made of the triggering level of the protection and the impedance value of the component depending on the ESD stress amplitude. No information on the transient behavior of the protections is included in this model. It is not possible to predict some failures related to the transient phenomenon of the protection like triggering and turning on time that induce very high overvoltage or mismatch on the current levels estimation. The various topics covered during this thesis allows to solve these problems by using a, proposed dynamic model. Different methods are proposed to extract the parameters used into the dynamic model. One important point also aborted into this document is that the model have to be able to predict the soft failure which can appear in the system during an ESD stress.[...]
10

Intelligent power module for variable speed AC motor drives

Allaith, Noori A. January 1997 (has links)
No description available.

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