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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Electro-Optic Phase Modulation, Frequency Comb Generation, Nonlinear Spectral Broadening, and Applications

Oscar E Sandoval (6887678) 15 August 2019 (has links)
<p>Electro-optic phase modulation can be used to generate high repetition rate optical frequency combs. The optical frequency comb (OFC) has garnered much attention upon its inception, acting as a crucial component in applications ranging from metrology and spectroscopy, to optical communications. Electro-optic frequency combs (EO combs) can be generated by concatenating an intensity modulator and phase modulator together. The first part of this work focuses on broadening the modest bandwidth inherent to the EO combs. This is achieved by propagation in a nonlinear medium, specifically propagation in a nonlinear optical loop mirror (NOLM). This allows for broadening the EO frequency comb spectrum to a bandwidth of 40 nm with a spectral power variation of < 10 dB. This spectrally broadened EO comb is then used in dual comb interferometry measurements to characterize the single soliton generated in an anomalous dispersion silicone-nitride microresonator. This measurement allows for rapid characterization with low average power. Finally, electro-optic phase modulation is used in a technique to prove frequency-bin entanglement. A quantum network based on optical fiber will require the ability to perform phase modulation independent of photon polarization due to propagation in optical fiber scrambling the polarization of input light. Commercially available phase modulators are inherently dependent on the polarization state of input light making them unsuited to be used in such a depolarized environment. This limitation is overcome by implementing a polarization diversity scheme to measure frequency-bin entanglement for arbitrary orientations of co- and cross- polarized frequency-bin entangled photon pairs.</p>
142

CAD-Based Pose Estimation - Algorithm Investigation

Lef, Annette January 2019 (has links)
One fundamental task in robotics is random bin-picking, where it is important to be able to detect an object in a bin and estimate its pose to plan the motion of a robotic arm. For this purpose, this thesis work aimed to investigate and evaluate algorithms for 6D pose estimation when the object was given by a CAD model. The scene was given by a point cloud illustrating a partial 3D view of the bin with multiple instances of the object. Two algorithms were thus implemented and evaluated. The first algorithm was an approach based on Point Pair Features, and the second was Fast Global Registration. For evaluation, four different CAD models were used to create synthetic data with ground truth annotations. It was concluded that the Point Pair Feature approach provided a robust localization of objects and can be used for bin-picking. The algorithm appears to be able to handle different types of objects, however, with small limitations when the object has flat surfaces and weak texture or many similar details. The disadvantage with the algorithm was the execution time. Fast Global Registration, on the other hand, did not provide a robust localization of objects and is thus not a good solution for bin-picking.
143

Automatic parameter tuning in localization algorithms / Automatisk parameterjustering av lokaliseringsalgoritmer

Lundberg, Martin January 2019 (has links)
Many algorithms today require a number of parameters to be set in order to perform well in a given application. The tuning of these parameters is often difficult and tedious to do manually, especially when the number of parameters is large. It is also unlikely that a human can find the best possible solution for difficult problems. To be able to automatically find good sets of parameters could both provide better results and save a lot of time. The prominent methods Bayesian optimization and Covariance Matrix Adaptation Evolution Strategy (CMA-ES) are evaluated for automatic parameter tuning in localization algorithms in this work. Both methods are evaluated using a localization algorithm on different datasets and compared in terms of computational time and the precision and recall of the final solutions. This study shows that it is feasible to automatically tune the parameters of localization algorithms using the evaluated methods. In all experiments performed in this work, Bayesian optimization was shown to make the biggest improvements early in the optimization but CMA-ES always passed it and proceeded to reach the best final solutions after some time. This study also shows that automatic parameter tuning is feasible even when using noisy real-world data collected from 3D cameras.
144

Uma abordagem heurística para o corte de itens irregulares em múltiplos recipientes / A heuristic approach for cutting irregular items in multiple containers

Mundim, Leandro Resende 25 March 2015 (has links)
Problemas de corte e empacotamento de itens irregulares são problemas que visam determinar um leiaute ótimo de objetos pequenos dentro de objetos maiores, a fim de atender a uma demanda. Estes problemas têm grande importância prática, já que surgem em vários tipos de indústria (como a têxtil, a de móveis e a de calçados). O problema estudado neste trabalho é o problema de corte de itens irregulares em recipientes. Os recipientes são delimitados e o objetivo é encontrar um leiaute dos objetos menores, sem sobreposição, dentro dos objetos maiores utilizando a menor quantidade de recipientes. Propomos um novo método de resolução para o problema. Nosso método é um algoritmo que gerencia um conjunto de heurísticas, de baixo nível, específicas para a resolução do problema com recipientes retangulares e irregulares. Recipientes irregulares são polígonos convexos e não convexos, que podem ser furados. As heurísticas desenvolvidas utilizam uma malha de pontos sobre a técnica de no-fit polygon para evitar a sobreposição dos itens e encontrar posições viáveis no recipiente retangular ou irregular. Os experimentos computacionais foram feitos para um grande conjunto de instâncias, de recipientes retangulares e irregulares. Os resultados demonstram a competitividade do método, que obtêm resultados bons e algumas soluções ótimas, em um tempo computacional aceitável. / Cutting and packing of irregular items are problems that aim to determine the optimum layout of small objects within larger objects (that we call bins), in order to meet a demand. These problems have great practical importance, since they emerge in various types of industry (such as textile, furniture and shoemaking). The problem studied in this work is the irregular bin packing problem. The bins are enclosed and the goal is to find a layout of items, without overlap, within the bins by using the minimum quantity of them. We propose a new method of resolution to this problem. Our method is an algorithm that manages a set of low-level heuristics, specific to solve the problem with rectangular bins and irregular bins. Irregular bins are convex and non-convex polygons, which may contain holes. The developed heuristics uses a mesh of points and the technique of no-fit polygon to avoid the overlapping of items and find feasible positions in rectangular or irregular bins. The computational experiments were performed for a large set of instances, using both rectangular and irregular bins. The results demonstrate the competitiveness of the method, which can get good results and some optimal solutions within an acceptable computational time.
145

I betraktarens ögon : En historiedidaktisk studie av läroböckers innehåll och lärares resonemang om elfte septemberattacken och dess konsekvenser / In the eyes of the beholder : A didactic study of Swedish teachers and textbooks in history´s reasoning about nine eleven and its aftermath.

Svanström, Emma, Johansson, Emmy January 2014 (has links)
"In the eye of the beholder- A didactic study of Swedish teachers and textbooks in history’s reasoning about nine eleven and its aftermath" by Emmy Johansson and Emma Svanström aims to show which picture both teachers and textbooks on elementary school and upper secondary school want to mediate on the subject. The study also strives to compare the teachers view with the textbooks. To achieve these goals the study uses materials from eight interviews and fifteen textbooks. The methods are a combination of interviews and textual analysis inspired by the scientist Elizabeth D. Herman. Comparison was also included in order to be able to compare teachers and textbooks. Content analysis and sentence centralization was used in order to analyze the materials. Finally the study used a combination of theoretical concepts which included history didactics, historically consciousness and facts about the production of textbooks. The results show that although there is a great variation in how teachers as well as textbooks reason about the subject there are also many similar thoughts and presentations. This is the case for as well teachers as textbooks and the comparison between them. The study also reveal that although teachers are skeptical about the textbooks they are both needed to form a good education. But such a combination would still leave some effects unmentioned to the students.
146

Köpa på efterfrågan : en utvärdering av BIN-projektets försöksverksamhet

Fredriksson, Anneli, Lindblom, Helena January 2005 (has links)
In 2003 the libraries of ten municipalities in the northern part of Sweden were each given 10 000 (SEK) by the BIN-project to purchase books on demand instead of making inter-library loans. This attempt was called Köpa på efterfrågan (Purchasing on demand). The purpose of this master thesis is to evalutate Köpa på efterfrågan. The results of the evaluation show that the books purchased on demand were quite popular. Almost all the purchased books were non-fictional with most books being bought within the field of medicin. There is also a correspondence between the education held in the participating municipality and which subject the purchased books belonged to. The libraries have all made rather similar purchases regarding subject, with the exception of Robertsfors. The most expensive subject was medicin, both per book and overall. The libraries have mostly bought their books on Internet bookstores due to their low cost and swift delivery. Purchasing on demand entails more benefits than inter-library lending, as it is less expensive, and a book, once bought, is available on the shelf for others to borrow it, although the increase of the library’s collection demands more thorough media-planning.
147

Formgivning av en papperskorg / Design of a Paper Bin

Hörling, Anton January 2018 (has links)
Sammanfattning Denna rapport dokumenterar ett examensarbete för högskoleingenjörsprogrammet i innovationsteknik och design, vårterminen 2018 vid Karlstads universitet. Examensarbetet är utfört enligt konventionell produktutvecklingsprocess i ett uppdrag om att ta fram en papperskorg för SPAZA, ett svenskt företag som tillhandahåller exklusiva produkter för spaoch hotellmiljöer. Samtliga produkter i sortimentet är inom ramen för SPAZAs material- och tillverkningsrestriktion: laserskuren, bockad samt pulverlackerad rostfri stålplåt. Syftet med projektet är att tillämpa erhållen kunskap från högskoleingenjörsprogrammet och med vetenskapligt underlag ta fram en papperskorg som ser till behoven genom alla led i dess livscykel. Detta utan att stil eller estetiskt uttryck kompromissas. Med en förstudie identifierades behov för tillverkning, frakt, montering samt användning av hotellgäst och städpersonal. Dessa behov formulerades öppet som primära och sekundära krav och tillsammans med det som redan på förhand specificerats av uppdragsgivaren bildades en produktspecifikation, som sedan användes som underlag för idégenerering. Vid idégenerering producerades ett flertal idéer på former och funktioner. Dessa kombinerades och bildade tillsammans helhetskoncept som utvecklades i ett modellarbete. Med hjälp av erkända metoder för sållning så valdes ett antal koncept som presenterades för uppdragsgivaren. Under ett konceptvalsmöte valdes ett koncept ut för vidareutveckling. Ett slutgiltigt koncept, Konceptet 4 som det kallas, härstammade ifrån en idé på funktionslösning om att använda plåtens fjädrande materialegenskaper för att hålla uppe påsen. Konceptet ser till behoven i de olika leden och möter totalt 30 av 31 stycken listade krav i en kriteriematris. En första CAD-modell på Koncept 4 skickades till CNC Plåt i Västervik för tillverkning av prototyp. Denna prototypen utvärderades och justerades därefter i enlighet med identifierade förbättringar i form och funktion. Dessa implementerades i en ny prototyp som godkändes av uppdragsgivaren som underlag för produktion. Projektet är avslutat och papperskorgen är ett steg närmare produktion. / Abstract This thesis documents a bachelor’s degree project for the engineering programme in Innovation Technology and Design, spring semester 2018 at Karlstad University. The project has been carried out in accordance with conventional product development process, in an assignment to design a paper bin for SPAZA; a Swedish company that provides elegant products for spa and hotel environments. All products in the assortment are within the SPAZA material and manufacturing specification: laser cut, bent and powder coated stainless steel sheet. The purpose of the project is to apply knowledge acquired from the engineering programme and, with a scientific basis, design a paper bin that considers the needs in all the different stages of its life cycle. This without compromising style or aesthetic expression. A pre-study identified the needs in manufacturing, shipping, assembly and use by hotel guests and cleaning staff. These needs were then formulated openly as primary and secondary requirements, and together with what had already been specified by the outsourcer, a product specification was formed, which was later used in idea generation. Idea generation produced a lot of ideas for forms and functions. These were combined, and together they formed concepts that were developed further in work with models. Recognized methods for screening were then used to determine which concepts that were of value to present to the outsourcer, and during a conceptual meeting a decision was made on which concept to realize. A final concept, Concept 4 as it was called, derives from an idea for function about using the sheet metal’s flexing material properties to hold up the bag. The concept meets the needs in the various life cycle stages with a total of 30 out of 31 fulfilled requirements listed in the product specification. A CAD model of Concept 4 was sent to CNC Plåt in Västervik for prototype manufacturing. The prototype was evaluated and adjusted in accordance with identified improvements in forms or function, and with a second version of the CAD model having been delivered to the outsourcer, the goal of the assignment was achieved. The project is finished, and the paper bin is one step closer to production.
148

A construção do conceito de inimigo nos discursos de Osama Bin Laden no período de 1996 a 2004

Souza, Bruno Mendelski de January 2012 (has links)
Objetivamos analisar a construção do conceito de inimigo representado nos discursos de Osama bin Laden, durante o período de 1996 a 2004. Estes inimigos são constituídos a partir da edificação de uma realidade que apresenta Estados Unidos, Israel e seus aliados, como opressores dos muçulmanos. A fim de melhor compreender esta construção simbólica, buscaremos estudá-la com base na dinâmica de dois eixos fundamentais para a constituição do pensamento político-religioso de bin Laden: a herança teórica do islamismo radical, conjugada com a sua percepção acerca dos principais eventos geopolíticos contemporâneos envolvendo o mundo muçulmano. Dentro desta perspectiva, empregaremos o construtivismo em sua corrente linguística dos autores Nicholas Onuf e François Debrix como arcabouço teórico. Nos guiaremos pela prerrogativa de que a compreensão do mundo e da realidade ocorre de acordo com o modo como nós nos referimos a eles a partir de nossa linguagem. Como referencial metodológico que orientará nosso exame da construção do conceito de inimigo nos discursos de bin Laden, utilizaremos as categorias de operação da ideologia propostas por John Thompson na obra “Ideologia e Cultura Moderna – Teoria Social Crítica na Era dos Meios de Comunicação”. / We aimed to analyze the construction of the concept of enemy represented in Osama bin Laden‟s speeches, during the period 1996 to 2004. These enemies are making from the building of a reality that presents U.S., Israel and its allies, as oppressors of muslims. To better understand this symbolic construction, we will seek to study it based on the dynamics of two pillars for the constitution of bin Laden's politico-religious thought: the theoretical heritage of radical islam, combined with the author's perception about the main events contemporary geopolitical involving the muslim world. From this perspective, we will employ the Linguistic Constructivism of the authors Nicholas Onuf and François Debrix, as theoretical framework. We will be guided by the prerogative of the understanding of the world and reality occurs according to the way we refer to them from our language. As a methodological framework that will guide our examination of the construction of the concept of enemy in bin Laden's speeches, we will use the categories of operation of ideology proposed by John Thompson in his work "Ideology and Modern Culture - Critical Social Theory in the Era of the Media."
149

Modélisation eulérienne de la vidange d'un silo et de l'expansion du panache / Eulerian simulation of dust emission by powder discharge and jet expansion

Audard, François 20 December 2016 (has links)
De nombreux procédés industriels nécessitent la manipulation de matériaux sous forme pulvérulente. L’émission de poussières générée par leur manipulation peut s’avérer dangereuse pour la santé des travailleurs ou bien causer un risque d’explosion. Afin de mieux comprendre les mécanismes de dispersion des poussières, le cas de la décharge d’un silo est étudié par simulation numérique avec une approche Euler-Euler. Deux configurations ont été étudiées au cours de cette thèse. La première, sans silo, a permis d’étudier l’influence de perturbations de vitesses imposées à l’entrée de la chambre de dispersion en lieu et place du silo. Cette étude a révélé que ces perturbations peuvent influencer l’élargissement du panache de poudre. Seules les perturbations avec une corrélation temporelle ont généré une ouverture importante du jet tombant semblable à celle relevée expérimentalement. Dans la deuxième configuration, le silo et la chambre de dispersion sont représentés afin d’étudier le couplage entre la dispersion du jet et l’écoulement dans le silo. L’une des difficultés de ces simulations est de prédire les différents régimes d’écoulements granulaires, allant de l’état quasi-statique dans le silo au régime très dilué lors de la dispersion du jet tombant, en passant par le régime collisionnel à la sortie du silo. La théorie cinétique permet de modéliser le régime dilué et collisionnel. En revanche pour la partie quasi-statique un modèle semi-empirique a été utilisé, implémenté et validé sur différentes configurations. La seconde étude a montré l’importance du rapport entre le diamètre de l’orifice et le diamètre des particules sur la structure du jet. En effet, lorsque ce paramètre est faible, le coeur du jet se contracte immédiatement après la sortie du silo puis s’ouvre en aval. Pour des valeurs grandes, l’ouverture du jet est négligeable. Cependant, il semblerait que l’angle du silo modifie le comportement de l’écoulement, ce qui nécessitera des études supplémentaires. / A wide range of industrial processes requires the handling of granular material in a pulverulent form. The subsequent dust emissions due to these processes can be harmful to the health of workers or hazardous explosion risks. In order to understand dust dispersion mechanisms, a case of a free falling granular jet discharged from a silo is studied by numerical simulations using an Euler-Euler approach. Two types of numerical simulation are conducted. First, the influence of velocity fluctuations at the inlet chamber is studied on the plume behavior, instead of the silo. This study reveals that fluctuations are enable to reproduce the jet expansion. It is established that only fluctuations with temporal correlation generate a large jet opening similar to the experiment. The second type of setup shows the coupling between the silo and the chamber. One of the major challenges is the ability to predict the different flow regimes going from quasi-static regime inside the silo, to the very dilute regime in the dust spread and include the collisional regime occurs through the silo. Kinetic theory allows modeling of the dilute and collisional regime. By contrast, frictional models have been used, implemented and validated in different cases. The second study highlights the key role of the ratio defined by the orifice diameter on the particle diameter. Indeed, when this parameter is small, the jet powder core contracts immediately after the exit of the silo dump plane and expands downstream. For high values, the granular jet does not exhibit dispersion anymore. This study suggests that the silo half-angle has an impact on the flow field which justifies the need for further investigations.
150

An?lise wavelet e modelo de manchas em curvas de luz estelares dos telesc?pios espaciais Kepler e CoRoT / Wavelet analysis and spot model applied to stellar light curves from Kepler and CoRoT space missions

Castrillon, Jenny Paola Bravo 22 December 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-22T19:28:11Z No. of bitstreams: 1 JennyPaolaBravoCastrillon_TESE.pdf: 21271647 bytes, checksum: 8adb4a5df0dbdb4f20b049cb610cd4d2 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-23T21:59:10Z (GMT) No. of bitstreams: 1 JennyPaolaBravoCastrillon_TESE.pdf: 21271647 bytes, checksum: 8adb4a5df0dbdb4f20b049cb610cd4d2 (MD5) / Made available in DSpace on 2016-03-23T21:59:10Z (GMT). No. of bitstreams: 1 JennyPaolaBravoCastrillon_TESE.pdf: 21271647 bytes, checksum: 8adb4a5df0dbdb4f20b049cb610cd4d2 (MD5) Previous issue date: 2014-12-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / An?logas ?s manchas e f?culas fotosf?ricas solares, cuja visibilidade ? modulada por rota??o estelar, as regi?es ativas estelares consistem em grupos de manchas escuras na superf?cie da estrela e f?culas brilhantes causadas pelo seu campo magn?tico. Atualmente, as manchas estelares est?o bem estabelecidas como os principais marcadores usados para estimar o per?odo de rota??o estelar. Por outro lado, o comportamento din?mico das manchas tamb?m pode ser utilizado para analisar outros fen?menos relevantes, tais como a presen?a de atividade magn?tica e os seus ciclos. Para determinar o per?odo de rota??o estelar, identificar a presen?a de regi?es ativas e investigar se a estrela manifesta ou n?o rota??o diferencial, aplicamos dois m?todos: uma an?lise wavelet e um modelo de manchas. O procedimento wavelet tamb?m ? aplicado na an?lise de pulsa??es e na busca por assinaturas espec?ficas para esta variabilidade estelar particular dentre os diferentes tipos de estrelas vari?veis pulsantes. A transformada wavelet tem sido usada como uma ferramenta poderosa para o tratamento de v?rios problemas em astrof?sica. Neste trabalho mostramos que a an?lise em tempo-frequ?ncia das curvas de luz estelares, utilizando a transformada wavelet, ? uma ferramenta pr?tica para a identifica??o de rota??o, atividade magn?tica e assinaturas de pulsa??o. Apresentamos a composi- ??o espectral e as varia??es multiescala das s?ries temporais para quatro classes de estrelas: alvos dominados pela atividade magn?tica, estrelas com planetas, aquelas com tr?nsitos bin?rios, e estrelas pulsantes. Aplicamos a wavelet Morlet de 6 a ordem, que oferece alta resolu??o em tempo e frequ?ncia. Ao aplicar a transformada wavelet no sinal, obtemos os espectros de pot?ncia wavelet local e global. O primeiro ? interpretado como a distribui??o de energia do sinal no espa?o tempo-frequ?ncia, e o segundo ? obtido por integra??o temporal do mapa local. Sendo a transformada wavelet uma ferramenta matem?tica ?til para sinais n?o estacion?rios, esta t?cnica aplicada v ?s curvas de luz, obtidas a partir das miss?es espaciais Kepler e CoRoT, nos permite identificar claramente determinadas assinaturas para diferentes fen?menos. Em particular, foram identificados padr?es para a evolu??o temporal do per?odo de rota??o, bem como uma outra periodicidade decorrente dos efeitos das regi?es ativas nas curvas de luz analisadas; a continuidade de uma determinada escala (frequ?ncia) durante a maior parte do tempo pode representar um indicador de rota??o e atividade. Al?m disso, uma assinatura de padr?o de batimento no mapa wavelet local de estrelas pulsantes ao longo de todo o tempo tamb?m foi detectada. O segundo m?todo ? baseado na detec??o de manchas estelares durante os tr?nsitos de um planeta extrasolar que orbita sua estrela-m?e. Quando um planeta eclipsa sua estrela-m?e ? poss?vel detectar fen?menos f?sicos que ocorrem na superf?cie da estrela. Se uma mancha escura na superf?cie estelar ? eclipsada parcial ou totalmente, a luminosidade estelar integrada aumentar? ligeiramente. A an?lise da curva de luz medida durante um tr?nsito planet?rio nos permite inferir propriedades f?sicas das manchas estelares como o tamanho, a intensidade, a posi??o e a temperatura. Ao detectar a mesma mancha em tr?nsitos consecutivos, ? poss?vel obter informa??es adicionais, como o per?odo de rota??o estelar na latitude do tr?nsito planet?rio, a rota??o diferencial, e os ciclos de atividade magn?tica. Observa??es do tr?nsito planet?rio nas estrelas CoRoT-18 e Kepler-17 foram usadas para aplicar este modelo. / Analogous to sunspots and solar photospheric faculae, which visibility is modulated by stellar rotation, stellar active regions consist of cool spots and bright faculae caused by the magnetic field of the star. Such starspots are now well established as major tracers used to estimate the stellar rotation period, but their dynamic behavior may also be used to analyze other relevant phenomena such as the presence of magnetic activity and its cycles. To calculate the stellar rotation period, identify the presence of active regions and investigate if the star exhibits or not differential rotation, we apply two methods: a wavelet analysis and a spot model. The wavelet procedure is also applied here to study pulsation in order to identify specific signatures of this particular stellar variability for different types of pulsating variable stars. The wavelet transform has been used as a powerful tool for treating several problems in astrophysics. In this work, we show that the time-frequency analysis of stellar light curves using the wavelet transform is a practical tool for identifying rotation, magnetic activity, and pulsation signatures. We present the wavelet spectral composition and multiscale variations of the time series for four classes of stars: targets dominated by magnetic activity, stars with transiting planets, those with binary transits, and pulsating stars. We applied the Morlet wavelet (6th order), which offers high time and frequency resolution. By applying the wavelet transform to the signal, we obtain the wavelet local and global power spectra. The first is interpreted as energy distribution of the signal in time-frequency space, and the second is obtained by time integration of the local map. Since the wavelet transform is a useful mathematical tool for nonstationary signals, this technique applied to Kepler and CoRoT light curves allows us to clearly identify particular signatures for different phenomena. In particular, patterns were identified for the temporal evolution of the rotation period and other periodicity due to active regions affecting these light curves. In addition, a beat-pattern vii signature in the local wavelet map of pulsating stars over the entire time span was also detected. The second method is based on starspots detection during transits of an extrasolar planet orbiting its host star. As a planet eclipses its parent star, we can detect physical phenomena on the surface of the star. If a dark spot on the disk of the star is partially or totally eclipsed, the integrated stellar luminosity will increase slightly. By analyzing the transit light curve it is possible to infer the physical properties of starspots, such as size, intensity, position and temperature. By detecting the same spot on consecutive transits, it is possible to obtain additional information such as the stellar rotation period in the planetary transit latitude, differential rotation, and magnetic activity cycles. Transit observations of CoRoT-18 and Kepler-17 were used to implement this model.

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