To see the other types of publications on this topic, follow the link: Integral losses.
Dissertations / Theses on the topic 'Integral losses'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 31 dissertations / theses for your research on the topic 'Integral losses.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Lambert, Alex. "Learning function-valued functions in reproducible kernel Hilbert spaces with integral losses : Application to infinite task learning." Electronic Thesis or Diss., Institut polytechnique de Paris, 2021. http://www.theses.fr/2021IPPAT016.
Full textAbstract:
Les méthodes à noyaux sont au coeur de l'apprentissage statistique. Elles permettent de modéliser des fonctions à valeurs réelles dans des espaces de fonctions à fort potentiel représentatif, sur lesquels la minimisation de risques empiriques régularisés est possible et produit des estimateurs dont le comportement statistique est largement étudié. Lorsque les sorties ne sont plus réelles mais de plus grande dimension, les Espaces de Hilbert à Noyaux Reproduisants à valeurs vectorielles (vv-RKHSs) basés sur des Noyaux à Valeurs Opérateurs (OVKs) fournissent des espaces de fonctions similaires et permettent de traiter des problèmes tels que l'apprentissage multi-tâche, la prédiction structurée ou la régression à valeurs fonctionnelles. Dans cette thèse, nous introduisons une extension fonctionnelle originale du cadre multi-tâche appelée Apprentissage d'un Continuum de Tâches (ITL), qui permet de résoudre conjointement un continuum de tâches paramétrées, parmi lesquelles la régression quantile, la classification à coût assymétrique, ou l'estimation de niveaux de densité. Nous proposons un cadre d'apprentissage basé sur des fonctions de pertes intégrales qui comprend à la fois l'ITL et la régression à valeurs fonctionnelles, ainsi que des méthodes d'optimisation pour résoudre les problèmes de minimisation de risque empirique régularisé résultants. Par un échantillonage des pertes intégrales, nous obtenons une représentation de dimension finie des solutions pour différents choix de régularisation ou pénalités liées à la forme des fonctions, tout en gardant un contrôle théorique sur les capacités en généralisation des estimateurs. L'usage de la dualité lagrangienne vient approfondir ces méthodes, en apportant en particulier les moyens d'imposer des estimateurs parcimonieux ou robustes à l'aide de pertes convoluées. Les problèmes de passages à l'échelle sont traités par l'utilisation noyaux approchés, dont les vv-RKHSs associés sont de dimension finie. Nous proposons aussi une architecture composée d'un réseau de neurone et d'une dernière couche à noyaux, qui permet l'apprentissage de représentations appropriées aux noyaux utiles dans les applications avec des données complexes comme les images. Ces techniques sont appliquées à plusieurs problèmes d'ITL, ainsi qu'au problème de régression fonction-à-fonction robuste en présence de valeurs aberrantes. Enfin, nous revisitons les problemes de transfert de style sous l'angle ITL, avec une application au transfert d'émotionKernel methods are regarded as a cornerstone of machine learning.They allow to model real-valued functions in expressive functional spaces, over which regularized empirical risk minimization problems are amenable to optimization and yield estimators whose statistical behavior is well studied. When the outputs are not reals but higher dimensional, vector-valued Reproducible Kernel Hilbert Spaces (vv-RKHSs) based on Operator-Valued Kernels (OVKs) provide similarly powerful spaces of functions, and have proven useful to tackle problems such as multi-task learning, structured prediction, or function-valued regression.In this thesis, we introduce an original functional extension of multi-output learning called Infinite Task Learning (ITL), that allows to jointly solve an infinite number of parameterized tasks, including for instance quantile regression, cost-sensitive classification and density level set estimation.We propose a learning framework based on convex integral losses that encompasses the ITL problem and function-valued regression. Optimization schemes dedicated to solving the associated regularized empirical risk minimization problems are designed. By sampling the integral losses, we derive finite-dimensional representation of the solution under several choices of regularizers or shape constraints penalties, while keeping theoretical guarantees over their generalization capabilities. We also employ dualization techniques with the benefit of bringing desirable properties such as robustness or sparsity to the estimators thanks to the use of convoluted losses. Scalability issues are addressed by deriving optimization algorithms in the the context of approximated OVKs whose corresponding vv-RKHSs are of finite dimension. The use of trainable deep architectures composed by a neural network followed by a shallow kernel layer is also investigated as a way to learn the kernel used in practice on complex data such as images.We apply these techniques to various ITL problems and to robust function-to-function regression, that are tackled in the presence of outliers. We also cast style transfer problems as a vectorial output ITL problem and demonstrate its efficiency in emotion transfer
2
Lucca, Walter. "PESO CORPORAL E FITASE NA DIGESTIBILIDADE VERDADEIRA DO FÓSFORO NO FARELO DE ARROZ INTEGRAL PARA SUÍNOS." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/4354.
Full textAbstract:
Two studies were carried out in the Department of Animal Science, Federal University of Santa Maria, with the objective of determining the effect of body weight and phytase on the total true digestibility (DTVP) and endogenous phosphorus loss (PEL) of rice bran (RB) using linear regression technique. The sample was composed of 24 castrated pigs, being 12 animals with 13 ± 1 kg and 46 days old, and 12 animals with 57 ± 2.5 kg and 86 days old. The animals were divided into six treatments consisted of diets with three levels (5, 10 and 20%) of RB and two levels of phytase (0 and 750 FTU/kg-1). Semi-purified diets were used with inclusion of blood plasma as a source of amino acids and Ca:P ratio of 2:1. Ferric oxide was used as a fecal marker. The experiments were conducted in three periods of 12 days each, being 7 days for adaptation and 5 days for total collection of feces. The total amount of feed was calculated based on the lowest consumption and provided in four meals a day, while water was ad libitum. Between each 12 day-period a diet was provided during three days to meet the nutritional requirements of the animals. Pigs were housed in 24 cages with adjustable metabolisms according to their body weight. The room temperature was maintained at 22°Celsius, using air conditioners. The variables were subjected to analysis of variance using the effect of period, animal, treatments and interactions in the model. The average weight in the piglets did not change in relation to the phytase and the RB. On the other hand, the intake of dry matter DMI(g/d); excreted dry matter DME(g/d) and digestible dry matter DMD(%); ingested phosphorus PI(g/d); excreted phosphorus PE(g/d) and absorbed phosphorus PAbs(g/d) were significant by the level of RB and not significant the phytase, while the digestible the PD(%) was significant for phytase and RB. The DTVP and EPL of RB with and without the addition of phytase resulted 47.51% and 425.2mgP/kgDMI, R2=91% and 34.39% and 461.1 mgP/kgDMI, R2=97%, respectively. The addition of phytase in the diet reduced 6.76% the P excretion and the P coming from the RB reduced 38.46%. In the growth phase, live weight and DMI(g/d) the DME(g/d), DMD(%) and PI(g/d) and PAbs(g/d) were significant for RB. The PE(g/d) and PD(%) were influenced significant by phytase and RB. The DTVP and EPL of RB with and without phytase resulted 58.42% and 439.7mgP/kgDMI, R2 = 92.4% and 32.10% and 260.8mgP/kgDMI, R2 = 93.2%, respectively. There was a reduction of the PE with the addition of phytase in 27.92% and with the P coming from RB the reduction was 36.25%. The use of phytase in semi-purified diets with added RB promoted a reduction of fecal excretion of P in both studied weights and, consequently, there was
an increase in the DTVP. However, the effect of the enzyme was more pronounced in higher body weight of pigs (38 vs 45%). Phosphorus levels in serum did not change in the studied time periods for either phases and RB is rich in P. Much of this P is in the form of phytate with low digestibility, thus phytase has a significant role in providing this mineral, contributing in the increase of RB nutritional value.Dois estudos foram conduzidos no Setor de Suinocultura do Departamento de Zootecnia da Universidade Federal de Santa Maria, com o objetivo de determinar o efeito do peso vivo e da fitase na digestibilidade total verdadeira (DTVP) e perdas endógenas de fósforo (PETP) do farelo de arroz integral (FAI), através da técnica de regressão linear. Utilizaram-se 24 suínos castrados, sendo 12 animais com 13 ± 1 kg e 46 dias de idade e 12 animais com 57 ± 2,5 kg e 86 dias de idade. Os animais foram distribuídos em seis tratamentos, que consistiram de dietas formuladas com três níveis (5, 10 e 20%) de FAI e dois níveis de fitase (0 e 750 FTU/kg-1). Foram utilizadas dietas semipurificadas com inclusão de plasma sanguíneo (Ps) como fonte de aminoácidos e relação Ca:P de 2:1. O óxido férrico foi utilizado como marcador fecal. Os experimentos foram conduzidos em três períodos (blocos) de 12 dias, sendo 7 dias destinados à adaptação e 5 dias destinados à coleta total de fezes. A quantia total de ração fornecida foi calculada com base no menor consumo e fornecida em quatro refeições diárias, enquanto a água foi disponibilizada à vontade. Entre cada período de 12 dias foi fornecida uma dieta formulada para atender as necessidades nutricionais dos animais. Os suínos foram alojados em 24 gaiolas de metabolismo ajustáveis de acordo com o peso corporal. A temperatura ambiente foi mantida em 22ºC, utilizando-se condicionadores de ar. As variáveis foram submetidas à análise de variância utilizado no modelo o efeito do bloco, animal, tratamentos e as interações. O peso médio na fase de creche não sofreu alteração em relação à fitase e ao FAI. Já a matéria seca ingerida MSI (g/d), matéria seca excretada (g/d) e matéria seca digestível (%), fósforo ingerido PI (g/d), fósforo excretado (g/d), fósforo absorvido (g/d) foram significativo aos níveis de FAI, enquanto o fósforo digestível (%) foi significativo a fitase e farelo de arroz integral. A DTVP e PETP no FAI com e sem adição da fitase resultaram (47,51% e 425,2 mgP/kgMSI, R2 = 91,0%) e (34,39% e 461,1mgP/kgMSI, R2 = 97%), respectivamente. A adição da fitase reduziu a excreção de P na dieta em 6,76% e no P oriundo do FAI em 38,46%. Na fase de crescimento não houve significância do peso vivo e MSI (g/d) para fitase e FAI. A MSE (g/d), MSD (%) e PI (g/d) e PAbs (g/d) foram significativos ao FAI. O PE (g/d) e PD (%) foram influenciados significativamente pela fitase e farelo de arroz integral. A DTVP e PETP no FAI com e sem fitase resultaram (58,42% e 439,7 mgP/kgMSI, R2=92,4%) e (32,10% e 260,8 mgP/kgMSI, R2=93,2%), respectivamente. Houve redução do PE com adição de fitase em 27,92% e com o P oriundo do FAI 36,25%. Concluiu-se que o uso de fitase em dietas semipurificadas com adição de FAI promoveu redução da excreção fecal do fósforo em ambos os pesos estudados e, em decorrência, aumentou a DTVP. Entretanto, o efeito da fitase foi mais pronunciado nos suínos de maior peso corporal (38 versus 45%). Os níveis de P no soro sanguíneo não sofreram alteração nos períodos estudados para ambas as fases e o farelo de arroz integral é rico em P, sendo que grande parte desse encontra-se na forma de fitato com baixa digestibilidade, e a fitase tem papel significativo na disponibilização desse mineral, contribuindo no aumento do valor nutricional desse alimento.
3
Баранник, Валентин Сергеевич. "Пространственная аэродинамическая оптимизация направляющей решетки осевой турбины." Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22677.
Full textAbstract:
Диссертация на соискание ученой степени кандидата технических наук по специальности 05.05.16 – турбомашины и турбоустановки. – Национальный технический университет "Харьковский политехнический институт", Харьков, 2016. Диссертация посвящена разработке методики пространственной аэродинамической оптимизации направляющих решеток осевых турбин путем поиска оптимальных формы профилей и меридиональных обводов межлопаточных каналов. Использование данной методики позволяет при решении оптимизационной задачи учесть дополнительные резервы повышения эффективности. Поиск оптимального варианта осуществлялся с использованием теории планирования эксперимента и ЛПτ – последовательности. Для описания полимодальных целевых функций исходная формальная макромодель в виде полного квадратичного полинома была уточнена путем замены суперпозиции параболы на суперпозицию кубического интерполяционного сплайна. На основе разработанной методики проведена оптимизация направляющей решетки третьей степени мощной паровой турбины с постоянным по высоте профилем при построении его различными типами кривых. Анализ результатов оптимизации показал, что наибольшее снижение интегральных потерь составило 7% в относительных величинах. Снижение потерь было достигнуто, как в ядре потока, так и в области вторичных течений. Существенно влиять на структуру течения в турбинных решетках, а следовательно получать дополнительных выигрыш при постановке оптимизационной задачи позволяет меридиональное профилирование поверхностей межлопаточного канала. Оптимизация периферийного меридионального обвода с помощью разработанного метода позволила дополнительно снизить интегральные потери 1,4%. в относительных величинах. Построение формы меридионального обвода осуществляется с использованием кривых Безье 4-го порядка для решеток без раскрытия и 3-го порядка – для решеток с раскрытием. Использование лопатки переменного по высоте профиля при постановке оптимизационной задачи также позволяет снизить интегральные потери.Thesis for degree of Candidate of Sciences in Technique for speciality 05.05.16 – turbomachine and turbo-installation. – National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. The thesis is devoted to development the methods of the three-dimensional aerodynamic optimization of axial turbine nozzle cascades by defining the optimal shape of profiles and nozzle channel meridional shape. The formulation of an optimization problem using this methods allows to consider the additional efficiency reserves.While implementing developed method design of the turbine profiles using different kinds of curves was carried out. For each of the curve types the control parameters that allow to widely vary the profile geometry were determined. The results reliability was confirmed by providing verification of the nozzle and blade cascade simulations with experimental data. Using developed methods the optimization of the third stage nozzle cascade with a constant height profile of the powerful steam turbine using different types of curves was conducted. As a result of optimization the largest reduction of the integral losses by 7% in relative values was shown. Further optimization of the shroud meridional shape using developed optimization method increased this value by 1.4%. Formulation optimization task Using variable nozzle height profile also reduces the integral loses.
4
Бараннік, Валентин Сергійович. "Просторова аеродинамічна оптимізація направляючої решітки осьової турбіни." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/22676.
Full textAbstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.05.16 – турбомашини та турбоустановки. – національний технічний університет "Харківський політехнічний інститут", Харків, 2016. Дисертація присвячена розробці методики просторової аеродинамічної оптимізації напрямних решіток осьових турбін шляхом пошуку оптимальних форми профілів та меридіональних обводів міжлопаткових каналів. Використання даної методики дозволяє при постановці оптимізаційної задачі врахувати додаткові резерви підвищення ефективності. При реалізації цієї методики було виконано проектування турбінних профілів з використанням різного роду кривих. Для кожного типу кривої визначені її параметри управління, що дозволяють в широких межах варіювати геометрію профілю. Достовірність отриманих результатів підтверджується проведеною верифікацією на направляючій та робочій решітці. На основі розробленої методики проведено оптимізацію направляючої решітки третього ступеня потужної парової турбіни з постійним по висоті профілем при побудові його різними типами кривих. Аналіз результатів оптимізації показав, що найбільше зниження інтегральних втрат склало 7% у відносних величинах. Подальша оптимізація периферійного меридіонального обводу за допомогою розробленого методу дозволила збільшити цю величину на 1,4%. Використання лопатки перемінного по висоті профілю при постановці оптимізаційної задачі також дозволяє знизити інтегральні втрати.Thesis for degree of Candidate of Sciences in Technique for speciality 05.05.16 – turbomachine and turbo-installation. – National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. The thesis is devoted to development the methods of the three-dimensional aerodynamic optimization of axial turbine nozzle cascades by defining the optimal shape of profiles and nozzle channel meridional shape. The formulation of an optimization problem using this methods allows to consider the additional efficiency reserves.While implementing developed method design of the turbine profiles using different kinds of curves was carried out. For each of the curve types the control parameters that allow to widely vary the profile geometry were determined. The results reliability was confirmed by providing verification of the nozzle and blade cascade simulations with experimental data. Using developed methods the optimization of the third stage nozzle cascade with a constant height profile of the powerful steam turbine using different types of curves was conducted. As a result of optimization the largest reduction of the integral losses by 7% in relative values was shown. Further optimization of the shroud meridional shape using developed optimization method increased this value by 1.4%. Formulation optimization task Using variable nozzle height profile also reduces the integral loses.
5
Statra, Yazid. "Contribution à la modélisation et à la caractérisation des supraconducteurs HTC pour leur intégration dans les machines électriques." Electronic Thesis or Diss., Université de Lorraine, 2021. http://www.theses.fr/2021LORR0112.
Full textAbstract:
Les travaux de recherche présentés dans cette thèse constituent une contribution à la modélisation et à la caractérisation expérimentale de supraconducteurs à haute température critique (HTC) en vue d’une meilleure intégration dans les machines électriques. Les travaux ont été menés sur deux axes complémentaires : - Développement d'approches de modélisation permettant le calcul des grandeurs électromagnétiques dans les supraconducteurs HTC sous champ propre ou à proximité d’autres sources, et, notamment en présence de pièces ferromagnétiques à perméabilité magnétique linéaire et non linéaire. Un intérêt particulier est porté aux méthodes intégrales qui présentent plusieurs avantages pour la modélisation de tels systèmes. Les résultats obtenus ont été validés par des comparaisons aux mesures et à des calculs numériques par la méthode des éléments finis. - Caractérisation expérimentale de ces matériaux afin de déterminer le courant critique en courant continu (DC) et les pertes dissipées en courant alternatif (AC). L'étude va de l'élément de base (rubans supraconducteurs) au système (machine électrique), montrant les difficultés rencontrées dans une telle caractérisation. Un prototype de machine synchrone à induit supraconducteur a également été réalisé et testé. Les premiers résultats de mesure obtenus sont présentés et validés par modélisationThe research work presented in this thesis constitutes a contribution to the modeling and experimental characterization of high temperature superconductors (HTS) for a better integration in electrical machines. The work was carried out on two complementary axes: - Development of modeling approaches allowing the calculation of electromagnetic quantities in HTS under self-field conditions or with the proximity of other sources, in particular in the presence of ferromagnetic parts with linear and non-linear magnetic permeability. Particular interest is given to integral methods which have several advantages for the modeling of such systems. The results obtained were validated by comparisons with measurements and numerical calculations by the finite element method. - Experimental characterization of such materials in order to determine the critical current and AC losses. The study goes from the sample (superconducting tape) to the system (electrical machine), highlighting the difficulties encountered in such a characterization. A prototype of a synchronous machine with a superconducting armature was also built and tested. The first measurement results obtained are presented and validated by modeling
6
Minaya, Salguero Carlos Eduardo. "Planeamiento integral de obra y proceso constructivo de un edificio multipropósito." Bachelor's thesis, Pontificia Universidad Católica del Perú, 2008. http://tesis.pucp.edu.pe/repositorio/handle/123456789/1081.
Full textAbstract:
El tema de la presente tesis se centra en mostrar el proceso y los conceptos del
planeamiento integral y proceso constructivo de un edificio que puede utilizarse
para distintos fines, sea comercial o de oficinas, de allí el nombre de multipropósito.
Se realizó una evaluación desde los puntos de vista técnico y económico de
cuatros diferentes sistemas de losa de entrepiso, la losa de viguetas aligeradas
convencional, la losa maciza, la losa aligerada con viguetas pretensadas y la losa
con placa colaborante, asimismo se realizó la evaluación de una escalera de
concreto con una escalera metálica, las últimas mencionadas en cada caso, fueron
las utilizadas en la construcción del edificio multipropósito.
Para desarrollar estos temas, se dividió la tesis en siete capítulos, en el primero se
desarrolla la memoria descriptiva en el cual se hace la presentación del proyecto,
en el segundo se muestran las especificaciones técnicas describiendo los procesos
constructivos de cada una de las partidas que intervienen, en el tercero se
presentan los metrados de obra, en el cuarto se describe el proceso de elaboración
de los análisis de precios unitarios y los análisis comparativos mencionados en el
párrafo anterior, en el quinto se detalla el proceso de elaboración del presupuesto
de obra a nivel de costo directo, en el sexto se detalla el proceso de planeamiento
de obra en base a los datos desarrollados en los capítulos tercero y cuarto con el
soporte de los conceptos desarrollados en los otros capítulos, finalmente en el
capítulo séptimo se muestra el proceso constructivo mediante un reporte fotográfico
de la obra.
A través del desarrollo de la presente tesis se concluyó que el uso del sistema de
entrepiso de losa con placa colaborante y de la escalera metálica, es la opción
idónea para el tipo de proyecto analizado.
Por otro lado a lo largo de la tesis se dan pautas para mejorar y conocer a fondo el
planeamiento de una obra de construcción.Tesis
7
Lowe, Krispian Tom Edward. "Infrared polarimetry and integral field spectroscopy of post-asymptotic giant branch stars." Thesis, University of Hertfordshire, 2008. http://hdl.handle.net/2299/2449.
Full textAbstract:
In this thesis, I present the properties of IRAS 19306+1407 central source and its sur- rounding circumstellar envelope (CSE), from the analysis of near-infrared (near-IR) polarimetry and integral field spectroscopy (IFS), with supporting archived HST im- ages and sub-millimetre (sub-mm) photometry. This is supported by axi-symmetric light scattering (ALS), axi-symmetric radiative transfer (DART) and molecular hy-drogen (H2) shock models. The polarimetric images show that IRAS 19306+1407 has a dusty torus, which deviates from axisymmetry and exhibits a ‘twist’ feature. The DART and ALS modelling shows that the CSE consists of Oxygen-rich sub-micrometre dust grains, with a range in temperature from 130±30 to 40±20 K at the inner and outer radius, respectively, with inner and outer radii of 1.9±0.1×1014 and 2.7±0.1×1015 m. The CSE detached 400±10 years ago and the mass loss lasted 5700±160 years, assuming a constant asymptotic giant branch (AGB) outflow speed of 15 km s−1. The dust mass and total mass of the CSE is 8.9±5×10−4 and 1.8±1.0×10 −1 M⊙, assuming a gas-to-dust ratio of 200. The mass loss rate was 3.4±2.1×10−5 M⊙ year−1. The central source is consistent with a B1I-type star with a radius of 3.8 ± 0.6 R⊙, luminosity of 4500 ± 340 L⊙ at a distance of 2.7 ± 0.1 kpc. A purpose built idl package (fus) was developed and used in the SINFONI IFS data critical final reduction steps. It also produced emission line, kinematic and line ratio images. The IFS observations show that H2 is detected throughout the CSE, located in bright arcs and in the bipolar lobes. The velocity of the H2 is greatest at the end of the lobes. Brγ emission originates from, or close, to the central source – produced by a fast jump (J) shock or photo-ionised atomic gas. The 1-0 S(1)/2- 1 S(1) and 1-0 S(1)/3-2 S(3) ratios were used as a diagnostic and determined that H2 was excited by bow shaped shocks; however, these shock models could not wholly explain the observed rotational and vibrational temperatures. The CDR values were fitted by combining continuous (C) or J-bow shock and fluorescence models, with a contribution from the latter, observed throughout the CSE (5–77 per cent). The majority of shock can be described by a C-bow shock model with B = 0.02 to 1.28 mG. Shocks are predominately seen in the equatorial regions. Polarimetry and IFS highlight a ‘twist’ feature, which could be due to an episodic jet undergoing a recent change in the outflow direction. The sub-arcsecond IFS observations reveal a flocculent structure in the south- east bright arc, consisting of several clumps interpreted as a fast-wind eroding an equatorial torus, possibly forming H2 knots seen in (some) evolved planetary nebulae (PNe). My analysis has effectively constrained the following: spectral type, stellar radius, luminosity and distance, chemistry, dust grain properties, geometry, age, mass loss, excitation mechanism and evolutionary state of the post-AGB star and its surrounding CSE. I conclude that IRAS 19306+1407 is a post-AGB object on the verge becoming a PN.
8
Rahman, M. E. "Integrated full vectorial FEM, FDTD and diffraction integrals in characterising visible light propagation through lossy biological media." Thesis, City, University of London, 2015. http://openaccess.city.ac.uk/15935/.
Full textAbstract:
In this thesis, the propagation characteristics of the biological optical waveguides, considering the materials as lossy in the optical frequencies, have been analysed. It has been found that the losses present in the biological materials in optical frequencies are not negligible, and the loss values have significant effects on the propagation characteristics of these waveguides. In biological optical waveguides, each waveguide is surrounded by parallel waveguides so that the propagation characteristics would be different from that of single waveguide present in a homogeneous material. In this thesis, the impacts of the presence of the neighbouring waveguides on the propagation characteristics of a waveguide are studied in details. Dispersion characteristics of the waveguides have been investigated, and the effects of the material loss, presence of the neighbouring waveguides and the presence of multi-layer W-fibre like structure on the dispersion characteristics have also been studied. The modal characteristics, the time-domain evolution of the signal and the diffraction characteristics have been integrated to explain some of the still unanswered questions in the visual systems. An attempt has been made to explain the Stiles-Crawford effect of human retina in light of the findings of this thesis. A full-vectorial H-field based finite element method (FEM) is used for the modal solutions, Finite Difference Time Domain (FDTD) is used to study the time evolution of the signals through the waveguides, and the Diffraction profiles have been obtained by Rayleigh-Sommerfeld(RS) diffraction integral.
9
Vasconcellos, Vagner. "Proposição de um sistema integrado de gestão de transformadores." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-13082007-154218/.
Full textAbstract:
O transformador de potência é o ativo mais valioso e importante de uma subestação, razão pela qual se faz necessário um acompanhamento especial para estes equipamentos. A operação de qualquer equipamento fora de suas condições nominais é sempre uma situação de risco, porém, tal risco pode ser minimizado através de estudos e análises particulares para cada equipamento.Com os transformadores de potência isso não é diferente, as normas e guias de aplicação de cargas em transformadores prevêem períodos de sobrecarga dentro de algumas condições, porém, há uma grande incerteza nesses dados já que cada transformador envelhece de forma diferente ainda que sejam idênticos de projeto e fabricação. Por essa razão se faz necessária uma análise particular de cada equipamento onde serão identificados os riscos em potencial e a partir daí determinado o grau de confiabilidade do equipamento. Com base em informações históricas dos equipamentos e algoritmos desenvolvidos com base nas normas vigentes, foi desenvolvido o Sistema Integrado de Gestão denominado SGT. Através deste sistema será possível armazenar de forma organizada as informações de todas as unidades fornecendo subsídios para uma tomada de decisão minimizando os riscos. Através do Sistema Integrado será possível estabelecer uma base única de consultas, promovendo assim a otimização destes equipamentos face a regulação do setor elétrico.The power transformer is the most valuable and important assets of a substation, for that reason is necessary a special attendance for these equipments. The operation of any equipment out of their nominal conditions it is always a risk situation, however, such a risk can be minimized through studies and private analyses for each equipment. Power transformers are not different, the norms and guides of load application foresee overload periods under some conditions, however, and there is a great uncertainty in those data since each transformer ages in a different way although they are identical of project and production. For that reason are necessary peculiar analysis of each equipment where you/they will be identified the potential risks and since then certain the degree of reliability of the equipment. Based in historical informations of the equipments and algorithms developed in agreement with the effective norms, the Integrated System of Management was developed and denominated SGT. Through this system it will be possible to store in an organized way the information of all of the units, supplying subsidies to have a safe decision minimizing the risks. Through the Integrated System it will be possible to establish an only base of consultations, promoting the assets optimization based in the new regulation of the electric section.
10
Gil, Camilo. "An Optimal Control Approach for Determiniation of the Heat Loss Coefficient in an ICS Solar Domestic Water Heating System." Doctoral diss., University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2567.
Full textAbstract:
Water heating in a typical home in the U.S. accounts for a significant portion (between 14% and 25%) of the total home's annual energy consumption. The objective of considerably reducing the home's energy consumption from the utilities calls for the use of onsite renewable energy systems. Integral Collector Storage (ICS) solar domestic water heating systems are an alternative to help meet the hot water energy demands in a household. In order to evaluate the potential benefits and contributions from the ICS system, it is important that the parameter values included in the model used to estimate the system's performance are as accurate as possible. The overall heat loss coefficient (Uloss) in the model plays an important role in the performance prediction methodology of the ICS. This work presents a new and improved methodology to determine Uloss as a function of time in an ICS system using a systematic optimal control theoretic approach. This methodology is based on the derivation of a new nonlinear state space model of the system, and the formulation of a quadratic performance function whose minimization yields estimates of Uloss values that can be used in computer simulations to improve the performance prediction of the ICS system, depending on the desired time of the year and hot water draw profile. Simulation results show that predictions of the system's performance based on these estimates of Uloss are considerably more accurate than the predictions based on current existing methods for estimating Uloss.Ph.D.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering PhD
11
Vakanas, Loizos Petrou 1964. "An integral equation method for the evaluation of the frequency-dependent per unit length inductance and resistance matrices for a uniform multiconductor lossy transmission line system." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277100.
Full textAbstract:
The problem of electromagnetic field penetration in the finite-resistivity conductors of a uniform, multiple, coupled transmission line system (MTL) is considered. Under the assumption of quasi-transverse electric and magnetic (quasi-TEM) mode of propagation, the problem of determining the per-unit-length resistance and inductance matrices for such MTL systems reduces to solving a quasi-magnetostatic problem. An integral equation for the current density distribution inside the conductors is formulated and solved numerically using the method of moments. From straightforward energy considerations and the current density distribution, the per-unit-length resistance and inductance matrices are calculated. Several microstrip configurations are then analysed and the effects of the geometrical characteristics of the structures on the per-unit-length inductance and resistance matrices, as well as their frequency dependence are investigated.
12
Ferreira, Francisco Roberto Brandão. "Análise integrada de dados no estudo da dinâmica da terra em uma bacia hidrográfica : o caso do Rio Balsinhas-MA /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/100081.
Full textAbstract:
Orientador: Sérgio dos Anjos Ferreira PintoBanca: Ailton Luchiari
Banca: Archimedes Perez Filho
Banca: Antonio Carlos Cavalli
Banca: José Ribamar Trovão
Resumo: O presente trabalho propõe uma aplicação de abordagem metodológica, com uso de geotecnologia, visando à aquisição, análise e integração de dados sob o enfoque do uso sustentável de uma bacia hidrográfica em área de fronteira agrícola voltada para o plantio de grãos para exportação. Para o seu desenvolvimento, foram levantados dados de uso da terra e cobertura vegetal em dois cenários distintos (1975 e 1999) e, direcionados a sua aplicação para a bacia hidrográfica do rio Balsinhas, no estado do Maranhão, localizada entre os paralelos 07º 27' 00" S e 08º 12' 51" S, de latitude sul, e os meridianos 45º 44' 54" W e 46º 07' 59" W, de longitude oeste. O trabalho visa ainda, caracterizar áreas com diferentes graus de predisposição a riscos à degradação dos solos e realizar análises sob o ponto de vista da cobertura vegetal e suas transformações impostas pela intensificação e ampliação da ocupação agrícola, bem como indicações de impactos ocorridos nas vertentes e nos canais fluviais ao longo da bacia.
Abstract: The present work proposes an application of a methodological approach, by means of geotechnology, which aims to data acquisition, analysis and network, concerning the self-support use a drainage basin located in agricultural border dedicated to grain crops for export. For their improvement, usage of soil and plant covering data in two distinct periods (1975 and 1999) were collected and their application addressed to a drainage basin of Balsinhas River, in the state of Maranhão, located between 07º 27' 00" and 08º 12' 51" parallels, south latitude, and 45º 44' 54" and 46º 07' 59" meridians, west longitude. This works also aims, to feature areas presenting different degrees to risks concerning soil degrading and to proceed to analysis on plant covering and its changes, which are imposed by the intensity and extension of agricultural occupation, as well as indications of impacts on slopes and river channels along the basin.
Doutor
13
Ferreira, Francisco Roberto Brandão [UNESP]. "Análise integrada de dados no estudo da dinâmica da terra em uma bacia hidrográfica: o caso do Rio Balsinhas-MA." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/100081.
Full textAbstract:
Made available in DSpace on 2014-06-11T19:30:27Z (GMT). No. of bitstreams: 0
Previous issue date: 2006-05-26Bitstream added on 2014-06-13T21:01:09Z : No. of bitstreams: 1
ferreira_frb_dr_rcla.pdf: 891415 bytes, checksum: b556d691c96336607d68d906e82d364f (MD5)O presente trabalho propõe uma aplicação de abordagem metodológica, com uso de geotecnologia, visando à aquisição, análise e integração de dados sob o enfoque do uso sustentável de uma bacia hidrográfica em área de fronteira agrícola voltada para o plantio de grãos para exportação. Para o seu desenvolvimento, foram levantados dados de uso da terra e cobertura vegetal em dois cenários distintos (1975 e 1999) e, direcionados a sua aplicação para a bacia hidrográfica do rio Balsinhas, no estado do Maranhão, localizada entre os paralelos 07º 27' 00 S e 08º 12' 51 S, de latitude sul, e os meridianos 45º 44' 54 W e 46º 07' 59 W, de longitude oeste. O trabalho visa ainda, caracterizar áreas com diferentes graus de predisposição a riscos à degradação dos solos e realizar análises sob o ponto de vista da cobertura vegetal e suas transformações impostas pela intensificação e ampliação da ocupação agrícola, bem como indicações de impactos ocorridos nas vertentes e nos canais fluviais ao longo da bacia.
The present work proposes an application of a methodological approach, by means of geotechnology, which aims to data acquisition, analysis and network, concerning the self-support use a drainage basin located in agricultural border dedicated to grain crops for export. For their improvement, usage of soil and plant covering data in two distinct periods (1975 and 1999) were collected and their application addressed to a drainage basin of Balsinhas River, in the state of Maranhão, located between 07º 27' 00 and 08º 12' 51 parallels, south latitude, and 45º 44' 54 and 46º 07' 59 meridians, west longitude. This works also aims, to feature areas presenting different degrees to risks concerning soil degrading and to proceed to analysis on plant covering and its changes, which are imposed by the intensity and extension of agricultural occupation, as well as indications of impacts on slopes and river channels along the basin.
14
Jeong, Jaehoon. "Analytical time domain electromagnetic field propagators and closed-form solutions for transmission lines." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1105.
Full text
15
Torres, Thomas Edson Lima. "AvaliaÃÃo comparativa: sistema de gestÃo especÃfico versus sistema integrado, o estudo de caso do beneficiamento da castanha de caju." Universidade Federal do CearÃ, 2004. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2103.
Full textAbstract:
nÃo hÃA escolha da estratÃgia ambiental a ser utilizada pelas empresas leva em consideraÃÃo se a empresa abordarà suas questÃes ambientais atravÃs de sistemas de gestÃo ambiental ou de sistemas integrados de saÃde, seguranÃa e meio ambiente, devendo esta escolha ser baseada no planejamento estratÃgico da empresa. Este trabalho possui como objetivo estudar em uma indÃstria de beneficiamento de castanha de caju, a adequaÃÃo de dois sistemas de gestÃo, um especÃfico de gestÃo ambiental baseado na NBR ISO 14001 e outro de gestÃo integrada de saÃde seguranÃa e meio ambiente baseado no controle de perdas. A metodologia utilizada apresenta inicialmente uma revisÃo dos principais modelos de estratÃgia ambiental, entre eles os modelos de Shrivastava, Hart, Heinhardt, Sharma e o de Stead & Stead. A partir daÃ, busca, atravÃs de um estudo de caso identificar a estratÃgia da empresa, a qual utiliza dois diferentes sistemas, um Sistema de GestÃo Ambiental e um sistema de gestÃo integrada de saÃde, seguranÃa e meio ambiente. Uma comparaÃÃo teÃrica baseada em uma revisÃo bibliogrÃfica apresenta as semelhanÃas e diferenÃas entre estes dois sistemas, e uma pesquisa realizada utilizando-se aplicaÃÃo de questionÃrios semi-estruturados aplicados aos gestores responsÃveis pelos sistemas, visa avaliar qual dessas duas ferramentas se apresenta como mais adequada para atingir os objetivos da estratÃgia ambiental da empresa. Os resultados obtidos mostraram que, o sistema de gestÃo ambiental baseado a NBR ISO 14001 obteve um pontuaÃÃo maior, de acordo com os questionÃrios aplicados, que o programa de controle de perdas CTP. A conclusÃo a respeito dos resultados mostra que para a empresa estudada, a gestÃo das questÃes ambientais, tratada atravÃs de um Sistema de GestÃo Ambiental se mostrou mais adequado que o sistema de gerenciamento integrado.
The choice of an environmental strategy by a firm must consider a set of variables, among them, whether a firm approaches its environmental issues through out a specific environmental management system or an integrated one. Therefore, this work aims to study the performance of two management systems â a specific environmental system based on the ISO 14001 and an integrated one based on the Total Loss Control â that are running simultaneously in a processing plant of cashew nuts in the State of CearÃ, Brazil. Based on the main models of environmental strategies â Shrivastava, Hart, Heinhardt, Sharma and Stead & Stead â we identify which strategies the industry adopts to solve its environmental problems. Analyzing the principles and elements that constitute each system, we point out structural similarities and differences among them. Finally, by applying a semi-structurated questionnaire to the managers responsible for the systems, we evaluate, using a Likert scale, which system was more appropriated to reach the environmental goals of the firm. We found that the specific system showed the highest avarage ponctuation according to the managerâs opinions. Therefore, we can conclude that the specific environmental system was better than the integrated system for dealing which the environmental issues in the cashew nut industry.
16
Torres, Thomas Edson Lima. "Avaliação comparativa: sistema de gestão específico versus sistema integrado, o estudo de caso do beneficiamento da castanha de caju." reponame:Repositório Institucional da UFC, 2004. http://www.repositorio.ufc.br/handle/riufc/16712.
Full textAbstract:
TORRES, Thomas Edson Lima. Avaliação comparativa: sistema de gestão específico versus sistema integrado, o estudo de caso do beneficiamento da castanha de caju. 2004. 86 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Pró-Reitoria de Pesquisa e Pós-Graduação, Mestrado em Desenvolvimento e Meio Ambiente - PRODEMA, Fortaleza-CE, 2004.Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-11T12:22:28Z No. of bitstreams: 1 2004_dis_teltorres.pdf: 535337 bytes, checksum: e865dbe05eb45cf7a03f06311ebbb8fa (MD5)
Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-05-11T12:22:41Z (GMT) No. of bitstreams: 1 2004_dis_teltorres.pdf: 535337 bytes, checksum: e865dbe05eb45cf7a03f06311ebbb8fa (MD5)
Made available in DSpace on 2016-05-11T12:22:41Z (GMT). No. of bitstreams: 1 2004_dis_teltorres.pdf: 535337 bytes, checksum: e865dbe05eb45cf7a03f06311ebbb8fa (MD5) Previous issue date: 2004
The choice of an environmental strategy by a firm must consider a set of variables, among them, whether a firm approaches its environmental issues through out a specific environmental management system or an integrated one. Therefore, this work aims to study the performance of two management systems – a specific environmental system based on the ISO 14001 and an integrated one based on the Total Loss Control – that are running simultaneously in a processing plant of cashew nuts in the State of Ceará, Brazil. Based on the main models of environmental strategies – Shrivastava, Hart, Heinhardt, Sharma and Stead & Stead – we identify which strategies the industry adopts to solve its environmental problems. Analyzing the principles and elements that constitute each system, we point out structural similarities and differences among them. Finally, by applying a semi-structurated questionnaire to the managers responsible for the systems, we evaluate, using a Likert scale, which system was more appropriated to reach the environmental goals of the firm. We found that the specific system showed the highest avarage ponctuation according to the manager’s opinions. Therefore, we can conclude that the specific environmental system was better than the integrated system for dealing which the environmental issues in the cashew nut industry.
A escolha da estratégia ambiental a ser utilizada pelas empresas leva em consideração se a empresa abordará suas questões ambientais através de sistemas de gestão ambiental ou de sistemas integrados de saúde, segurança e meio ambiente, devendo esta escolha ser baseada no planejamento estratégico da empresa. Este trabalho possui como objetivo estudar em uma indústria de beneficiamento de castanha de caju, a adequação de dois sistemas de gestão, um específico de gestão ambiental baseado na NBR ISO 14001 e outro de gestão integrada de saúde segurança e meio ambiente baseado no controle de perdas. A metodologia utilizada apresenta inicialmente uma revisão dos principais modelos de estratégia ambiental, entre eles os modelos de Shrivastava, Hart, Heinhardt, Sharma e o de Stead & Stead. A partir daí, busca, através de um estudo de caso identificar a estratégia da empresa, a qual utiliza dois diferentes sistemas, um Sistema de Gestão Ambiental e um sistema de gestão integrada de saúde, segurança e meio ambiente. Uma comparação teórica baseada em uma revisão bibliográfica apresenta as semelhanças e diferenças entre estes dois sistemas, e uma pesquisa realizada utilizando-se aplicação de questionários semi-estruturados aplicados aos gestores responsáveis pelos sistemas, visa avaliar qual dessas duas ferramentas se apresenta como mais adequada para atingir os objetivos da estratégia ambiental da empresa. Os resultados obtidos mostraram que, o sistema de gestão ambiental baseado a NBR ISO 14001 obteve um pontuação maior, de acordo com os questionários aplicados, que o programa de controle de perdas CTP. A conclusão a respeito dos resultados mostra que para a empresa estudada, a gestão das questões ambientais, tratada através de um Sistema de Gestão Ambiental se mostrou mais adequado que o sistema de gerenciamento integrado.
17
Duscha, Vicki [Verfasser], and K. M. [Akademischer Betreuer] Ehrhart. "No-lose targets as an option to integrate non-Annex I countries in global emission reduction efforts - A game-theoretical analysis / Vicki Duscha. Betreuer: K.-M. Ehrhart." Karlsruhe : KIT-Bibliothek, 2012. http://d-nb.info/1024729699/34.
Full text
18
Neves, Ademir Diniz. "Bioecologia e tabela de vida de fertilidade de Praelongorthezia praelonga (Douglas, 1891) (Hemiptera: Ortheziidae) em diferentes temperaturas e UR." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-13022014-083216/.
Full textAbstract:
O objetivo deste trabalho foi avaliar o desenvolvimento de Praelongorthezia praelonga (Douglas, 1891) em diferentes temperaturas e umidades relativas do ar, para definir áreas, no Estado de São Paulo, nas quais esta praga tenha maior possibilidade de aumentar o seu nível populacional, e, consequentemente causar maiores prejuízos. Neste sentido, a partir de criação estoque em cróton (Codeaum variegatum L.), cochonilhas recém nascidas foram transferidas para mudas de limoeiro Cravo (Citrus limonia L.) onde foram observados diversos parâmetros biológicos. Procedeu-se de forma análoga para avaliação dos parâmetros biológicos desta praga nas diferentes umidades relativas do ar, utilizando-se neste caso, como hospedeiro, tubérculos brotados de batata (Solanum tuberosum). Concluiu-se que as melhores temperaturas com base taxas liquidas de reprodução (R0) e razão finita de aumento (?), para o desenvolvimento de P. praelonga foram 22 e 25°C; a melhor umidade relativa do ar com base nas maiores taxa liquida de reprodução (R0) e razão finita de aumento (?) para P. praelonga foi 70%; a fase crítica, em qualquer condição térmica ou hídrica, para a criação de P. praelonga foi o primeiro ínstar para fêmeas, e o primeiro ínstar e a pseudo-ninfose para machos; em função das exigências térmicas, P. praelonga pode apresentar de 4,99 a 6,60 gerações anuais, nas principais áreas citrícolas de São Paulo; adultos e ninfas de P. praelonga preferiram as folhas maduras da região mediana da copa para escolha; a amostragem de P. praelonga deve ser feita com maior periodicidade nos períodos secos e frios do ano e em folhas da porção mediana das copas.The goal of this research was to evaluate the development of Praelongorthezia praeloga (Douglas, 1891) under different temperatures and relative humidity in order to define areas in the state of Sao Paulo where this pest is more likely to increase its population level thus causing higher losses. Through stock rearing of garden crotons (Codeaum variegatum L.), recently born mealybugs were transferred to \'Rangpur\' lime seedlings (Citrus limonia L.) and several biological parameters were observed. Similarly the evaluation of the biological parameters of the pest was performed under different relative humidity having, in this case, sprouting potato (Solanum tuberosum) tubers as host. The best temperatures based on net reproduction rates (R0) and finite ratio of increase (?) for the development of P. praelonga were 22 and 25°C; the best relative humidity based on the highest net reproduction rates (R0) and finite ratio of increase (?) for P. praelonga was 70%; the critical stage, under any thermal or moist condition, for P. praelonga rearing was the first instar for females and first instar and pseudo-nymphosis for males; regarding the thermal requirements, P. praelonga may reach 4.99 to 6.60 annual generations in the main citrus areas of Sao Paulo; P. praelonga adults and nymphs preferred mature leaves of the trees for fixation; the P. praelonga sampling must be carried out with higher periodicity in dry and cold periods of the year and in leaves of the central part of the tree.
19
Scott, Shane. "Rheological Properties of Protein Hydrogels." Thesis, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/20565.
Full textAbstract:
Certain hydrogel forming de novo proteins that utilize different crosslinking
methods are studied experimentally on a rheometer. The stress reaxation
modulus of CRC, a telechelic, triblock protein, is shown to be that of
a stretched exponential function with a value of β ≅ 0.5. The insertion of
an integrin binding domain and changes in pH within the range 6.5–8.5 are
shown not to significantly affect the resulting rheological behavior. A selective
chemical crosslinker is used on CRC hydrogel systems and is shown to
change the rheological behavior of the system to that of a combination of a
chemically and physically crosslinked system. Chemically crosslinked hydrogels
composed of W6, a wheat gluten-based protein, demonstrate a storage
modulus weakly dependent on the angular frequency that is much greater
than the loss modulus, with a modulus concentration dependence of c^9/4.
20
Bariteau, Jean-Marc. "Etude et réalisation d'anneaux résonnants en optique intégrée." Grenoble INPG, 1989. http://www.theses.fr/1989INPG0068.
Full textAbstract:
La technologie optique integree sur substrat silicium permet la realisation d'un microguide d'ondes en anneau couple a des microguides rectilignes formant ainsi une cavite resonante. Cette etude apporte des solutions theoriques et de premiers resultats experimentaux pour cet interferometre integre. Une presentation des resonances observables par interferences a ondes multiples est donnee puis l'influence des divers parametres sur les pics de resonance est etudiee. Une evaluation des pertes dues a la courbure de ces microguides est effectuee et le couplage entre microguides est calcule par la methode de perturbation. Les parametres technologiques utilisables sont ensuite determines pour differents rayons d'anneau et les caracteristiques de resonance des anneaux realises sont indiquees ainsi que les valeurs de pertes et de couplage qui s'en deduisent
21
Le, Luyer Yann. "Mise au point d'une technologie silice dopée erbium en optique intégrée pour l'amplification vers 1,5 µm." Grenoble INPG, 1997. http://www.theses.fr/1997INPG0184.
Full textAbstract:
L'application conjointe des principes de l'amplification optique et de l'optique integree permet la realisation d'amplificateurs plus compacts et susceptibles d'etre associes a d'autres composants optiques sur un meme substrat. Nous decrivons la mise au point d'une technologie en silice dopee erbium sur silicium pour l'amplification vers 1,5 m. Nous detaillons en particulier l'etape de depot de la couche guidante par pulverisation cathodique et l'etape de gravure. Les parametres de depot ont ete optimises pour obtenir des guides planaires homogenes en indice et epaisseur. Ces guides presentent de plus de faibles pertes de propagation. Par ailleurs, l'etude de la gravure de notre materiau nous a permis de determiner la chimie de gravure adequate, conduisant a une amelioration du profil de gravure et a une reduction de la rugosite des guides, source de pertes par diffusion. Les proprietes de luminescence de nos guides ont ete etudiees. Les resultats obtenus demontrent l'interet de notre technologie pour l'amplification. Toutefois, la duree de vie de l'erbium, qui influence directement le gain potentiel, depend largement du procede d'elaboration. Par exemple, l'etape de recouvrement suivie d'un recuit, entraine la diffusion d'hydrogene vers la couche guidante, ce qui degrade la dure de vie. Un gain de plusieurs db a ete mesure. Ce resultat sera largement ameliore par l'optimisation des caracteristiques de l'amplificateur optique integre, telles que la concentration en erbium, la structure du guide ou ses pertes de propagation.
22
"An efficient volume integral equation approach for characterization of lossy dielectric materials." 2004. http://library.cuhk.edu.hk/record=b6073666.
Full textAbstract:
Lui Man Leung."May 2004."
Thesis (Ph.D.)--Chinese University of Hong Kong, 2004.
Includes bibliographical references.
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Mode of access: World Wide Web.
Abstracts in English and Chinese.
23
Jiang, Peilin. "Time domain integral equation-based methods for analyzing electromagnetic scattering from objects residing in lossy media /." 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3292797.
Full textAbstract:
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007.Source: Dissertation Abstracts International, Volume: 68-12, Section: B, page: 8253. Adviser: Eric Michielssen. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.
24
Brito, Joana Rita Fernandes Castilho de. "Evaluation of hair dyes influence on the epidermal barrier using an in vitro test." Master's thesis, 2017. http://hdl.handle.net/10451/36040.
Full textAbstract:
Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2017The human being has the intrinsic desire to improve his appearance. Therefore, hair dyes have become a very popular product, which knows no gender or age barriers. According to statistics, more than 70% of women in developed world admit dyeing their hair at least once in their lifetime and most do so on a regular basis. Due to the extensive use of this type of products and their high chemical complexity, safety and legislation are very important aspects to ensure high standards of safety to consumers. Many users of these cosmetic products are not aware of the short-term and long-term effects they may cause. It is therefore important to study the influence these products can have on the skin, especially in the sensitization or irritation of the skin. This study aimed to study the influence of hair dyes on the epidermal barrier of the skin. The evaluation was performed indirectly using an in vitro model. Changes in the epidermal barrier were monitored through the measurement of TEWL, which is considered a criterion for the evaluation of skin barrier function. The first tests were performed using two controls: water as a negative control and a 20% SDS solution as a positive control. Subsequently, 10 different combinations were tested to evaluate the changes they can produced in the TEWL values, after their application, in relation to the basal values. It can be concluded that all the cosmetic products tested have a deleterious effect on the epidermal barrier of the skin, since all produced an increase in TEWL values. According to the results, there also appear to be no significant differences between the two brands tested and the effects produced on the epidermal barrier. Through this work, it was not possible to confirm the of involvement H2O2 in skin barrier disturbance, nor to relate the percentage and amount of H2O2 present in the formulation and the magnitude of the effects produced. The tests performed were considered insufficient to ascertain the relationship between the compounds tested and the effects produced on the skin, also not allowing elicit associations regarding a particular compound. On the other hand, the tests were performed using pig ear skin, which does not allow extrapolating results obtained for human skin.
O ser humano possui o desejo intrínseco de melhorar a sua aparência. As tintas para o cabelo tornam-se assim um produto cosmético muito popular, que não conhece barreiras de género ou etárias. A utilização de tintas para o cabelo remonta à época dos egípcios, há cerca de 4000 anos, onde as mulheres utilizavam um pó, feito a partir de folhas de henna, para pintar o cabelo, as unhas, ou até partes do corpo. Hoje em dia, podemos optar por pintar o cabelo em casa ou fazê-lo com um profissional num salão de cabeleireiros. Encontramos também ao nosso dispor uma grande variedade de cores, marcas e diferentes formas de colorir os nossos cabelos. Dentro desta categoria, as tintas permanentes possuem a maior quota de mercado, 80%. Existem inúmeras razões para a utilização de tintas para o cabelo, sendo a cobertura dos cabelos brancos apontada como a principal razão. Os aspetos psicológicos da transformação da cor do cabelo, relacionados muitas vezes com uma aparência mais jovem, são o principal impulsionador da utilização destes produtos cosméticos. De acordo com as estatísticas, mais de 70% das mulheres no mundo desenvolvido admitem pintar o seu cabelo pelo menos uma vez na vida e grande parte fá-lo de uma forma regular. Devido à extensa utilização deste tipo de produtos e à sua elevada complexidade química, a segurança e regulamentação são aspetos muito importantes para garantir elevados padrões de segurança para os consumidores. Em todo o mundo, a legislação de produtos cosméticos tem vindo a sofrer inúmeras mudança e a preocupação com os testes realizados em animais encontra-se no topo das prioridades. Na Europa, em 2003, foi publicada a 7ª Alteração à Diretiva de Cosméticos que estabeleceu a proibição de testes realizados em animais para ingredientes e produtos cosméticos acabados, bem como a proibição da sua comercialização. Em 2013, após um período de phasing out, esta lei entrou em vigor. Pelo contrário, na China, estima-se que todos os anos são usados entre 100.000 a 300.000 animais para testar produtos cosméticos. Em 2014, o governo chinês procedeu a algumas alterações e estabeleceu que para cosméticos comuns produzidos no próprio país, os testes em animais deixariam de ser um requisito obrigatório para a sua comercialização. Segundo as estimativas, a China tornar-se-á a maior potência mundial no que respeita ao mercado dos cosméticos, tornando-se preponderante terminar com os testes realizados em animais, sobretudo neste mercado. Muitos utilizadores destes produtos cosméticos não se encontram cientes dos efeitos que estes podem provocar, a curto e a longo prazo. Torna-se assim importante estudar a influência que estes produtos podem ter na pele, especialmente na sensibilização ou irritação da pele. Este trabalho teve como objetivo estudar a influência das tintas para o cabelo na barreira epidérmica da pele. A avaliação realizou-se indiretamente recorrendo a um modelo in vitro. Para a realização destes testes foi utilizada pele de orelha de porco, colocada em células de difusão de Franz. As alterações na barreira epidérmica foram monitorizadas através da medição da perda de água transepidérmica (TEWL), que é considerado um critério para a avaliação da função de barreira da pele. Os primeiros testes foram realizados utilizando dois controlos: a água como controlo negativo e uma solução de SDS com uma concentração de 20% como controlo positivo. Posteriormente, foram testadas 10 combinações diferentes de 8 cremes e quatro reveladores para avaliar a mudança produzida por estes nos valores de TEWL, após a sua aplicação, em relação aos valores basais, previamente medidos. Pode concluir-se que os todos os produtos cosméticos testados têm um efeito nocivo ao nível da barreira epidérmica da pele, uma vez que todos produziram um aumento nos valores de TEWL após a sua aplicação na pele. Segundo os resultados produzidos, parecem também não existir diferenças significativas entre as duas marcas testadas e os efeitos por estas produzidos ao nível da barreira cutânea. Através deste trabalho não foi possível confirmar a participação do H2O2 na perturbação da barreira da pele, nem relacionar a percentagem e a quantidade em que se encontra na formulação e a magnitude dos efeitos produzidos. Os testes realizados foram considerados insuficientes para averiguar a relação entre os compostos testados e os efeitos produzidos ao nível da pele, não permitindo também retirar elações acerca da relação entre um composto em particular e as mudanças verificadas na barreira epidérmica. Por outro lado, os testes foram realizados com recurso a pele de orelha de porco, o que não permite extrapolar os resultados obtidos para a pele humana.
25
Andrade, Sara Catarina Henriques. "The influence of different nanocarriers on skin’s biophysical parameters." Master's thesis, 2017. http://hdl.handle.net/10451/36158.
Full textAbstract:
Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2017Introduction & Aims: Nanotechnology is a new trend in cosmetology and lipid nanoparticles have shown higher degree of biocompatibility and versatility in this field compared to other systems. The aim of this research project was to evaluate the influence of three different systems containing lipid nanoparticles previously well characterized on skin hydration and transepidermal water loss (TEWL). Methods: Several formulations of lipid nanoparticles based systems (solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) with Dynasan® 114 (D114) or Glycerol monostearate (GMS) and nanoemulsions (NE)) were fully characterized (particle size, polydispersity index and zeta potential), and then incorporated into hydrogel form to study different skin parameters such as skin hydration and TEWL on forearms of six human volunteers. Results: The capacitance basal values of human volunteers before application of any hydrogel containing lipid nanoparticles were 31,48 (Control), 31,73 (SLN), 30,98 (NE), 30,42 (NLCD114) and 32,07 a.u. (NLCGMS). The TEWL basal values were 7,70 (Control), 7,55 (SLN), 7,72 (NE), 7,50 (NLCD114) and 7,67 g/h/m2 (NLCGMS). One hour after hydrogels` application, the capacitance values measured were 40,07 (Control), 43,20 (SLN), 41,22 (NE), 41,15 (NLCD114) and 44,15 a.u. (NLCGMS). At the same time, the TEWL values obtained were 6,58 (Control), 4,67 (SLN), 4,13 (NE), 3,90 (NLCD114) and 4,22 g/h/m2 (NLCGMS). Conclusion: The present study showed an increase in skin hydration after exposure to different systems of lipid nanoparticles (even not statistically significant). On the other hand, there was a statistically significant decrease in TEWL after that exposure, compared to the control. In this way, nanolipid systems, i.e. solid lipid nanoparticles, nanostructured lipid carriers and nanoemulsions, are promising systems to improve skin’s biophysical parameters in cosmetodermatology.
Introdução & Objetivos: A nanotecnologia é uma nova tendência no ramo da cosmetologia e as nanopartículas lipídicas têm demonstrado um maior grau de biocompatibilidade e versatilidade nesta área, comparando com outros sistemas já bem conhecidos. Este projeto de investigação teve como objetivo principal a avaliação da influência de três sistemas diferentes de nanopartículas lipídicas previamente bem caracterizados ao nível de parâmetros biofísicos da pele, nomeadamente hidratação da pele e perda transepidérmica de água. Métodos: Diversas formulações de sistemas baseados em nanopartículas lipídicas (nanopartículas lípidicas sólidas (SLN), vetores lipídicos nanoestruturados (NLC) formulados com Dynasan® (D114) ou Monoestearato de glicerol (GMS) e nanoemulsões (NE)) foram rigorosamente caracterizadas (nomeadamente o tamanho das partículas, índice de polidispersão e potencial zeta), sendo depois incorporadas na forma de hidrogel para ser avaliada a influência destes nanosistemas lipídicos em diferentes parâmetros biofísicos da pele, como a hidratação da pele e a perda transepidérmica de água nos antebraços de seis voluntários. Resultados: Os valores basais de capacitância nos voluntários antes da aplicação de qualquer hidrogel contendo nanopartículas foram 31,48 (controlo), 31,73 (SLN), 30,98 (NE), 30,42 (NLCD114) e 32,07 a.u. (NLCGMS). Os valores basais da perda transepidérmica de água foram 7,70 (controlo), 7,55 (SLN), 7,72 (NE), 7,50 (NLCD114) e 7,67 g/h/m2 (NLCGMS). Os valores da capacitância, uma hora após a aplicação dos hidrogeles, foram 40,07 (controlo), 43,2 (SLN), 41,22 (NE), 41,15 (NLCD114) e 44,15 a.u. (NLCGMS) e os valores de perda transepidérmica de água medidos após o mesmo período de tempo foram 6,58 (controlo), 4,67 (SLN), 4,13 (NE), 3,90 (NLCD114) e 4,22 g/h/m2 (NLCGMS). Conclusão: O presente estudo demonstrou um aumento na hidratação da pele após exposição a diferentes sistemas de nanopartículas lipídicas, mesmo não tendo sido estatisticamente significativo. Por outro lado, houve uma diminuição estatisticamente significativa na perda transepidérmica de água após essa mesma exposição, comparativamente ao valor registado no hidrogel controlo. Desta forma, os nanosistemas lipídicos (nanopartículas lipídicas sólidas, vetores lipídicos nanoestruturados e nanoemulsões) são sistemas promissores ao nível da melhoria dos parâmetros biofísicos da pele em Cosmética e Dermatologia.
26
Tavares, Liliana Patrícia da Veiga Durão Barbosa. "Caracterização da pele humana in vivo para melhor compreender a pele do doente obeso." Master's thesis, 2012. http://hdl.handle.net/10437/2871.
Full textAbstract:
Orientação : Luís Monteiro RodriguesO impacto da obesidade na fisiopatologia da pele humana parece relacionar-se com diversas dermatoses, resultado da alteração da sua fisiologia normal, incluindo alterações na função barreira e na função de “envelope”. Contudo, a informação disponível é ainda escassa devido às diversas complexidades do tema. Este estudo pretende contribuir para a definição de uma metodologia de abordagem experimental para estudar, de forma objetiva, as alterações funcionais que caracterizam a pele obesa. O presente estudo, transversal, incluiu 28 voluntárias, do sexo feminino, saudáveis, com idade média 23±5 anos de idade, após consentimento informado. Foi realizada uma única medição de caracterização das diversas funções cutâneas obtidas por meios não invasivos em condições controladas. As variáveis consideradas relevantes foram, a hidratação (superficial e profunda) a função de barreira e o comportamento biomecânico, medidos em 4 áreas anatómicas distintas. Através do SPSS (v 20.0) realizámos uma análise estatística univariada com cálculo de medidas de tendência central e de dispersão. Recorremos aos testes de Pearson e de Spearman, para as variáveis que seguiam, ou não, uma distribuição normal, respectivamente, adotando um grau de confiança de 95% . Os resultados permitem propor uma metodologia para o estudo da pele, aplicável ao doente obeso, incluindo a escolha das áreas anatómicas e das variáveis adequadas ao objetivo pretendido.
The impact of obesity in the pathophysiology of human skin seems to be related with various dermatoses, resulting from the change in its normal physiology, including changes in barrier function and the “envelope”function. However, the available information is still scarce because of the many complexities of the subject. This study pretends to contribute to the definition of a methodology for the experimental approach to study objectively the functional changes that characterize the obese skin. This transversal study included 28 volunteers, female, healthy, average age 23 ± 5 years, after informed consent. We performed a single measurement of skin characterization of the various functions obtained by non-invasive under controlled conditions. The variables considered as relevant, hydration (superficial and deep) barrier function and biomechanical behavior, measured at four different anatomical areas. Through the SPSS (v 20.0) conducted a univariate statistical analysis to calculate measures of central tendency and dispersion. We use the Pearson test and Spearman for variables that followed or not, a normal distribution, respectively, assuming a confidence level of 95%. The results allow us to propose a methodology for the study of the skin, apply to obese patients, including the choice of the anatomical areas and variables appropriate to the intended goal.
27
Silva, Fábio Miguel da Cruz. "Perda de peso em gatos seniores e geriátricos: abordagem diagnóstica em gatos com mais de doze anos." Master's thesis, 2014. http://hdl.handle.net/10437/5753.
Full textAbstract:
Orientação: Pedro Faísca ; co-orientação: Pedro AlmeidaIntrodução: O número de animais idosos tem crescido na população felina e a perda de peso é um dos sinais mais presentes nos mesmos. Torna-se necessária uma anamnese aprofundada bem como um exame físico minucioso e muitas vezes torna-se difícil chegar ao diagnóstico. Objetivo: Pretende-se determinar se a perda de peso é um indicador frequente em medicina felina, verificar a relação das características da amostra e sinais clínicos com a perda de peso, bem como determinar quais as doenças e os parâmetros analíticos mais associados. Materiais e métodos: Neste estudo foram incluídos 203 gatos, entre os 12 – 20 anos de idade, mínimo de 2 consultas/ano no Hospital Veterinário do Restelo com peso registado, desde 1 de Janeiro de 2012 até 30 Janeiro de 2014. Foi usado o programa Qvet® para pesquisa da informação. É um estudo retrospetivo, com uma abordagem quantitativa na vertente descritiva e inferencial. Resultados e conclusões: Na amostra estudada, 72,9% dos gatos perderam peso e 44,8% perderam pelo menos 10% do seu peso corporal. O aumento da idade e a raça siamesa associaram-se com a perda de peso, bem como a diarreia e anorexia. Nas causas, foi a nível metabólico que se verificou maior perda de peso e nos órgãos/sistemas, o fígado. Dos parâmetros analíticos, verificou-se maior correlação entre ureia, hemoglobina, hematócrito, creatinina e a perda de peso.
Introduction: The number of old animals in feline population has grown and weight loss is one of the major signs in this group. It is necessary a thorough medical history and a physical examination and often becomes difficult to get a diagnosis. Objective: The goal is to achieve whether weight loss is a common indicator in feline medicine, check the link of the sample information and clinical signs with weight loss as well as determine which diseases and more associated analytical parameters. Materials and methods: Present study included 203 cats were between 12-20 years old, who came to 2 visits / year , in Hospital Veterinário do Restelo , since January 1, 2012 until January 30, 2014. The Qvet® software was used to information research. It is a retrospective study with a quantitative approach to descriptive and inferential change. Results and conclusions: In this sample, 72.9 % of cats lost weight and 44.8 % lost at least 10 % of their body weight. Increasing age and breed Siamese were associated with weight loss, diarrhea and anorexia too. In causes, metabolic diseases showed higher weight loss associated with liver and kidney in organ/systems. In analytical parameters, there was an higher correlation between urea, hemoglobin, hematocrit, creatinine, and weight loss.
28
Borůvková, Klára. "Psychosociální intervence u žen s perinatální ztrátou." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-305636.
Full textAbstract:
This dissertation is focused on mapping the needs and development of experiencing the prenatal loss integration process in mothers, whose child died during the second or the third pregnancy trimester or suffered stillbirth. The goal of this dissertation is to suggest optimal intervention, which would prevent the progress of complications in terms of psychological disorders (PTSD, PAS). The theoretical part describes prenatal loss from the aspect of incidence and etiology and the loss of a close relative in general. It also focuses on the specifics of prenatal loss, the topic of crisis and its experience, phases of crisis, definition of the term "psychosocial intervention" and demarcation of its existing forms. This part also offers several perspectives and attitudes to the topic of grief as a process of hard life experience integration. It also describes several phases and problems connected with their fulfillment. The empirical part focuses on surveying the experiences and needs of women, who have suffered with prenatal loss. It also follows the approaches and circumstances, means of support, which helped women to cope with such an experience. It also tries to identify such aspects, which hindered this acceptation or made it more complicated. Research inquiry involves 13 depth interviews, which...
29
Ferreira, Joana Margarida Erse De Faria Godinho Ferreira. "Metodologias dinâmicas para avaliação da hidratação cutânea." Master's thesis, 2014. http://hdl.handle.net/10437/5859.
Full textAbstract:
Orientação: Catarina RosadoA pele é o maior órgão e o mais importante do nosso organismo, uma vez que nos protege contra, não só de agressões externas, como também da perda excessiva de água e electrólitos. Esta função de barreira é exercida pela sua camada mais externa, a epiderme, existindo diversos equipamentos de bioengenharia cutânea que permitem a sua medição. A primeira parte deste trabalho baseou-se na tentativa de optimização do protocolo do POST, pela redução do tempo total da experiência através da recolha de um maior número de pontos na fase inicial do estudo. A segunda parte deste trabalho baseou-se na confirmação de que o tempo de recolha de dados se demonstrou suficientemente sensível na avaliação da eficácia de dois tipos diferentes de cremes hidratantes, humectante e oclusivo.
Skin is the greater and foremost important organ in the human body, since it protects us from, not only, external agressions but excessive water loss as well. The barrier function depends mostly of the epidermis, and there are several bioengineering equipments that enable its assessment. The first part of this research was based on the optimization of the POST protocol, by reducing the total time of experience by taking a greater amount of data in the initial state of the study. The second part of the study was based on the confirmation that reducing the time of the initial part of the study was possible during the evaluation of two moisturizing creams, one of them humectant and the other occlusive.
30
Hallee, Brian Todd. "Feed-and-bleed transient analysis of OSU APEX facility using the modern Code Scaling, Applicability, and Uncertainty method." Thesis, 2013. http://hdl.handle.net/1957/37872.
Full textAbstract:
The nuclear industry has long relied upon bounding parametric analyses in predicting the safety margins of reactor designs undergoing design-basis accidents. These methods have been known to return highly-conservative results, limiting the operating conditions of the reactor. The Best-Estimate Plus Uncertainty (BEPU) method using a modernized version of the Code-Scaling, Applicability, and Uncertainty (CSAU) methodology has been applied to more accurately predict the safety margins of the Oregon State University Advanced Plant Experiment (APEX) facility experiencing a Loss-of-Feedwater Accident (LOFA). The statistical advantages of the Bayesian paradigm of probability was utilized to incorporate prior knowledge when determining the analysis required to justify the safety margins. RELAP5 Mod 3.3 was used to accurately predict the thermal-hydraulics of a primary Feed-and-Bleed response to the accident using assumptions to accompany the lumped-parameter calculation approach. A novel coupling of thermal-hydraulic and statistical software was accomplished using the Symbolic Nuclear Analysis Package (SNAP). Uncertainty in Peak Cladding Temperature (PCT) was calculated at the 95/95 probability/confidence levels under a series of four separate sensitivity studies.Graduation date: 2013
31
HUNG, KUO-TSAI, and 洪國在. "Everyone can tell the weather nowadays is very unstable and often turnsinto extremely severe conditions. As a result, it often causes a lot of damage toour agriculture and loss. Especially when there is a typhoon slashing our island,not only does it make our life inconvenient, but also evaporates our farmers’efforts in a short time so prices rise instantly. All of which have a significantimpact to our life.In order to reduce the impacts, some related units and private enterprisesare trying to find out the solutions for it. The government is also trying topromote the vegetable greenhouses for the reduction on the impact. However,its so pity that the promotion isn’t still being carried out practically.On the other side, the government also spares no efforts to promot thesolar electric energy, so under all conditions we may integrate PhotovoltaicSystems with Vegetables greenhouses to find out the best method to create awin-win situation for government, farmers and photovoltaic dealers." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f6nv3b.
Full textAbstract:
碩士正修科技大學
電機工程研究所
106
Everyone can tell the weather nowadays is very unstable and often turns into extremely severe conditions. As a result, it often causes a lot of damage to our agriculture and loss. Especially when there is a typhoon slashing our island, not only does it make our life inconvenient, but also evaporates our farmers’ efforts in a short time so prices rise instantly. All of which have a significant impact to our life. In order to reduce the impacts, some related units and private enterprises are trying to find out the solutions for it. The government is also trying to promote the vegetable greenhouses for the reduction on the impact. However, its so pity that the promotion isn’t still being carried out practically. On the other side, the government also spares no efforts to promot the solar electric energy, so under all conditions we may integrate Photovoltaic Systems with Vegetables greenhouses to find out the best method to create a win-win situation for government, farmers and photovoltaic dealers.