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C/O+ charge transfer & the Olson-Demkov modelBengtsson, Kristoffer January 2021 (has links)
Charge transfer reactions and their rates play a key role in correctly estimating element abundances in astrophysical objects such as supernovae. The reaction $C + O^+ \rightarrow C^+ + O(^1D) + \Delta E$ has been shown to be of significance when estimating oxygen abundances through model spectrum evaluations, and the relative rate of this reaction can under certain circumstances completely dictate the neutralization rate of oxygen ions. In this project, the rate of this reaction for four different temperatures is estimated using the Olson-Demkov model to calculate the cross section of the reaction as well as calculating rates for a few more reactions to compare to established literature values. We find that the Olson-Demkov model produces good estimates for reactions that have small energy defects (within an order of magnitude of more rigorous quantum mechanical calculations), but the model underestimates the rate coefficient by several orders of magnitude as the energy defect increases. As the investigated reactions are all exothermic, the energy defect is the released energy from the reaction (i.e., the energy defect is positive). It is also found in most cases that the Olson-Demkov model rate is poorly estimated by the rate coefficient based only on the cross section at the mean velocity, caused by the cross section rising rapidly for velocities higher than the mean. The rate estimates produced for C+O$^+$ are also likely to be underestimated, especially for the temperatures 100 and 1000 Kelvin. No literature comparison is available for this specific reaction, but this conclusion is consistent with the other investigated reactions. / Supernovor är bland de mest extrema fenomen vi kan observera i hela Universum. Dessa våldsamma explosioner lämnar spår efter sig i många år och har varit ovärdeliga objekt att observera för att lära oss mer hur vår galax och Universum har utvecklats över tid. Ljuset från supernovor och deras kvarlevor kan analyseras för att ta reda på vad för ämnen som finns kvar eller som har bildats av både explosionen och de processer som ägt rum efteråt. En typ av reaktion som är viktig för att fullt ut förstå dessa miljöer är så kallade "laddningsöverföringar", en reaktion där en laddad och en oladdad partikel interagerar med varandra varvid laddningen förflyttas mellan de två. Detta projekt har fokuserat på en modell som avser att räkna ut uppskattningar på hur sannolikt det är för dessa reaktioner att äga rum. Modellen, som kallas för Olson-Demkov-modellen, har även jämförts med andra modeller för att se under vilka förhållanden som den fungerar.
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Inspecting product quality with computer vision techniques : Comparing traditional image processingmethodswith deep learning methodson small datasets in finding surface defectsHult, Jim, Pihl, Pontus January 2021 (has links)
Quality control is an important part of any production line. It can be done manually but is most efficient if automated. Inspecting qualitycan include many different processes but this thesisisfocusedon the visual inspection for cracks and scratches. The best way of doingthis at the time of writing is with the help of Artificial Intelligence (AI), more specifically Deep Learning (DL).However, these need a training datasetbeforehand to train on and for some smaller companies, this mightnotbean option. This study triesto find an alternative visual inspection method,that does notrelyon atrained deep learning modelfor when trainingdata is severely limited. Our method is to use edge detection algorithmsin combination with a template to find any edge that doesn’t belong. These include scratches, cracks, or misaligned stickers. These anomalies arethen highlighted in the original picture to show where the defect is. Since deep learningis stateof the art ofvisual inspection, it is expected to outperform template matching when sufficiently trained.To find where this occurs,the accuracy of template matching iscompared to the accuracy of adeep learning modelat different training levels. The deep learning modelisto be trained onimage augmenteddatasets of size: 6, 12, 24, 48, 84, 126, 180, 210, 315, and 423. Both template matching and the deep learning modelwas tested on the samebalanceddataset of size 216. Half of the dataset was images of scratched units,and the other half was of unscratched units. This gave a baseline of 50% where anything under would be worse thanjust guessing. Template matching achieved an accuracy of 88%, and the deep learning modelaccuracyrose from 51% to 100%as the training setincreased. This makes template matching have better accuracy then AI trained on dataset of 84imagesor smaller. But a deep learning modeltrained on 126 images doesstart to outperform template matching. Template matching did perform well where no data was available and training adeep learning modelis no option. But unlike a deep learning model, template matching would not need retraining to find other kinds of surface defects. Template matching could also be used to find for example, misplaced stickers. Due to the use of a template, any edge that doesnot match isdetected. The ways to train deep learning modelis highly customizable to the users need. Due to resourceand knowledge restrictions, a deep dive into this subject was not conducted.For template matching, only Canny edge detection was used whenmeasuringaccuracy. Other edge detection methodssuch as, Sobel, and Prewitt was ruledoutearlier in this study.
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Fotoluminiscenční metody detekce defektů solárních článků / Solar cells photoluminescence defect detection methodsVala, Zbyněk January 2009 (has links)
This thesis discusses modern methods for fast defect detection of solar cells. For the means of the defect classification, the technological production process of crystalline silicon solar cells is described. The defects are researched by the electroluminescence and prohtoluminescence methods. The Photoluminiscence method is improved by the posibility of using different wavelenght of excitacion sources. The range of using in industrial production is determined for the discussed methods.
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Vliv teplotních závislostí luminiscence solárních článků / Influence of temperature dependence of luminescence solar cellsKoutný, Michal January 2010 (has links)
This work deals with determination defects in solar cells using non-destructive methods. Defects are determinating by electroluminescence method and microplasma method in temperature influence. Temperature will be changed by Peltier cells. By using this various temperatures during the testing we can receive more objective results thanks to simulated operation conditions.
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Analytické metody solárních panelů a systémů / Analytic method of solar panel and systemsKopunec, Vít January 2011 (has links)
The aim of the diploma work is to introduce analytical methods concerning solar panels and systems. Firstly, the attention is drawn to a principle of photovoltaic conversion including an explanation of photoelectric phenomenon as well as the issue of P-N junction considered to be the fundamental building block of a solar cell. With respect to the fact that the diploma work is to be focused on testing of solar panels and the identification of defects in solar cells, the work describes individual solar cells, solar panels as well as individual methods of defect identification. Secondly, the work includes sections dealing with the assessment of the measurement performed by using electroluminescence method as well as the measurement method of volt-ampere parameters. The last section of the work includes the assessment of solar panel aging after one-year performance using the electroluminescence measurement method.
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Vady a poruchy rezidenčních nemovitostí z pohledu tepelné techniky a jejich možný dopad na cenu nemovitosti / Faults and Defects of Residential Real Estate from the Point of View of Thermal Technique and their Possible Impact on the Value of the Real EstateHlavsa, Petr January 2014 (has links)
This master’s thesis deals with issues of faults and defects of building structures in residential real estate in terms of thermal technique. This thesis deals with their possible impact on the value of a residential real estate. In the theoretical part of this thesis, properties and quantities, which are used for an assessment of the building structures according to legislature, are described. Assessments of the steady state temperature are described closely. The thesis mentions usual sources and causes of faults and defects, which frequently occur. The possibilities of the non-destructive assessment of structures are also described. The reparability of faults or defects is related to the influence on the price of real estate. The practical part of the thesis deals with the value of a dwelling in an apartment house, which is affected by a fault manifesting surface condensation. An analyzed technical cause of this fault is described. Possible ways of remedying are shown, including the quantification of costs. The apartment is appraised in a faultless condition and afterwards the probable impact of this fault on the price of apartment is determined.
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Syntéza vysokopevnostních kompozitů na bázi anorganického cementu a polymeru / Synthesis of High-Strength Composites Based on Inorganic Cement and PolymerMásilko, Jiří January 2012 (has links)
The subject of the doctoral thesis is the study of moisture resistance of macro-defect-free (MDF) composites based on calcium-aluminate cement and polyvinylalcohol used as polymer. MDF cements are perspective materials providing unique properties relative to traditional cement pastes with great potential to incoming constructional utilization. But it is known that MDF cements exhibit sensitivity to water, with swelling and reduction of strength. Therefore the work is aimed in monitoring of an organic polymer effect on the moisture resistance of MDF materials and phase changes. The effects of three different organotitanate cross-linking agents on the properties were investigated. The organotitanate-modified MDF cement samples exhibited improved moisture resistance as compared to the standard samples when exposed to 100 % relative humidity or water at laboratory conditions. The influence of composition at different curing on the properties of model MDF cement samples was observed. The characterization of MDF samples was based especially on test of flexural strength, XRD, DTA/TGA and EGA, EDS and scanning electron microscopy analyses.
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Samočinný test ALU za provozu / ALU Built-In Self TestBednář, Jaroslav January 2010 (has links)
This work deals with faults, errors and failures, which can occur during manufacturing and long term operation. Work describes the various failures and fault models. There are some approaches to get fault tolerant systems, mainly in hardware. The thesis continues with a summary of methods for ALU software testing. The last chapter is about tests generation for microcontroller MSP430.
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Pasportizace stavebně-technického stavu rodinného domu v Hodoníně / Providing measured documentation of existing structural and technical conditions of a house in HodonínKadlčík, Radek January 2016 (has links)
The diploma thesis deals with solving passportization of the existing structural and technical conditions and the proposed modifications family house in Hodonin. The project includes theoretical part describing the defect of brick constructions and other related topics. Next explaining the problems of the building passportization, processing passport current state of the house in Hodonín with the marking of construction defects and failures. Followed by a proposal to repair these defects and failures, increased structural and technical standards. Preparation of a proposal modernization of the building. Compilation itemized budget for individual defects and failures.
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Folates et pathologies du neurodéveloppement : autisme et anomalies de fermeture du tube neural / Folates and neurodevelopment pathology : autism and neural tube defectRenard, Émeline 21 December 2018 (has links)
Les folates sont des vitamines importantes dans le développement neurologique d’un enfant puisqu’elles sont impliquées dans deux pathologies : l’autisme et les anomalies de fermeture du tube neural (AFTN). Une carence en vitamine B9 et la présence de certains polymorphismes des gènes du métabolisme des monocarbones sont associées à un risque augmenté d’anomalies de fermeture du tube neural. A l’inverse, une supplémentation périconceptionnelle en vitamine B9 a permis de réduire l’incidence de ces malformations. Dans le cadre de l’autisme, la présence d’anticorps dirigés contre le récépteur aux folates FR aplha au niveau cérébral entraînant une carence en folate cérébral a été décrite avec une fréquence importante chez les enfants autistes. Un traitement par acide folinique permettrait une amélioration des symptômes en corrigeant la carence en folates grâce à un passage médié par le RFC (récépteur non bloqué par les anticorps). La première partie est une étude clinique randomisée versus placebo réalisée au CHU de Nancy dont le but est d’évaluer l’éfficacité d’un traitement par acide folinique pendant 12 semaines sur la réduction des troubles autistiques. 19 enfants ont été inclus dans l’étude.Une amélioration significative des symptômes autistiques est observée pour le score ADOS dans le groupe traité (p= 0,02), plus particulièrement pour les interactions sociales réciproques (p=0,019). La fréquence des Anticorps anti FR alpha au sein du groupe est de 58 %. Il n’y a pas de corrélation observée entre le taux d’anticorps et l’importance de la réponse au traitement. Aucun effet secondaire grave n’a été observé au cours de l’étude. La seconde partie est une étude par séquençage haut débit d’un large panel de gènes chez des patients présentant des anomalies de fermeture du tube neural (SureSelect Focused Exome Plus (Agilent®)). Le séquençage a été complété par une analyse de méthylation pan-génomique (Infinium HumanMethylation Beadchip (Illumina®)). 23 patients ont été inclus dans l’étude. Plusieurs variants rares ont été identifiés comme associés au risque de AFTN dont des variants de gènes du métabolisme des monocarbones : LRP2, rs137983840, p=0,005; MMAA, rs148142853, p= 0,005 ;TCN2, rs35838082, p=0,044, FPGS, rs41306702, p=0,0012, BHMT, rs763726268, p= 0,011 et de la voie Sonic Hedgehog (SHH) (GLI3, rs35364414, p=0,012). Une différence de méthylation significative a été mise en évidence au niveau du gène CFAP46 (hémiméthylation versus absence de méthylation chez les contrôles) chez un patient porteur des 4 variants à risque identifiés (LRP2, MMAA, BHMT et GLI3). Ces résultats renforcent l’implication des folates dans ces deux pathologies du neurodéveloppement que sont l’autisme et les anomalies de fermeture du tube neural. Une recherche des anticorps anti-FRalpha plus systématique chez les enfants autistes pourrait permettre de proposer un traitement par acide folinique ciblé. Dans le cadre des AFTN, notre étude a mis en évidence l’influence de gènes impliqués dans le métabolisme de la vitamine B12 et monocarbone sur le risque de AFTN. Un nouveau gène candidat (GLI3) est identifié ainsi qu’une signature de méthylation mettant en évidence l’influence de la voie SHH / Folates are essentials vitamins in children neurodevelopment with an implication in two pathologies : autism and neural tube defects (NTD). Folates deficiency and some polymorphisms of genes involved in one carbon metabolism (OCM) are associated with NTD. Contrary, periconceptional folate supplementation is associated with decreased NTD frequency.In autism, higher frequency of antibodies against Folate Receptor Alpha (FR alpha) is rapported and associated with folates cerebral deficiency. Folinic acid treatment could improve autistic symptoms by correcting cerebral folate deficiency (cerebral transport mediated by RFC, an other receptor which not blocked by antibodies anti-FR alpha). First part is a randomized controlled trial versus placebo realized in CHU of Nancy in order to evaluate efficiency of folinic acid treatment during 12 weeks on autistic symptoms. 19 children have been included in the study. A significative improvement of autistic symptoms is observed by ADOS score in folinic acid group (p= 0.02) and particularly for mutual social interactions (p=0.012). FRalpha antibodies are present in 58 % of the group. We didn’t observed correlation between antibodies titers and folinic acid response. No serious adverse effects have been observed during the study. Second part is hight throughput next generation sequencing of DNA from patients with NTD using SureSelect Focused Exome Plus (Agilent®). Sequencing has been completed with DNA methylation analysis (Infinium HumanMethylation Beadchip (Illumina®)). 23 patients were included in the study. Six variants have been associated with NTD: from genes of B12 metabolism LRP2, rs137983840, p=0.005; MMAA, rs148142853, p= 0.005 and TCN2, rs35838082, p=0.044), folate cellular metabolism (FPGS, rs41306702, p=0.0012; choline metabolism, BHMT, rs763726268, p= 0.011) and Sonic Hedgehog pathway(SHH) (GLI3, rs35364414, p=0.012). A significative difference of methylation is identified in the vicinity of CFAP46 gene (hemimethylation versus no methylation in pseudo-controls) in one patient exhibited variants of BHMT, LRP2etMMAA. These results highlight implication of folates in these two pathologies of neurodevelopment, wich are autism and NTD. Anti-FRalpha should be routinely evaluated in case of autism in order to propose folinic acid treatment if they are positives. In the NTD study, we identified new variants from gene from one carbon metabolism probably implicated. A new candidate gene is identified (GLI3) and a methylation signature in association with B12 metabolism and OCM gene variants
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