Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-05-25T14:14:02Z No. of bitstreams: 1 TES_SERGIO_BOSCATO_GARCIA_COMPLETO.pdf: 4679313 bytes, checksum: 9d9d88508ab3cba6c986903ea518c84b (MD5) / Made available in DSpace on 2016-05-25T14:14:02Z (GMT). No. of bitstreams: 1 TES_SERGIO_BOSCATO_GARCIA_COMPLETO.pdf: 4679313 bytes, checksum: 9d9d88508ab3cba6c986903ea518c84b (MD5) Previous issue date: 2016-03-30 / The solar cell industry is based on manufacturing n+pp+ devices with phosphorus emitter and aluminum back surface field. Studies show that the exposure to solar radiation may cause the degradation of electrical characteristics of these devices, which does not occur in solar cells made with n-type silicon. Furthermore, ntype silicon has a highest minority carrier lifetime and it is less sensitive to the presence of impurities when compared to p-type substrates. With the goal of the development of p+nn+ solar cells, experimental manufacturing processes were carried out to produce devices with homogeneous emitter, obtained from BBr3 and spin-on dopant, selective emitter formed by laser radiation and deposition of the antireflection coating (AR) by evaporation and atmospheric pressure chemical vapor deposition (APCVD). In solar cells with homogeneous emitter formed by BBr3 and oxidation followed by annealing at 400 ?C with form ing gas provides a minimum surface passivation. It was observed that the electrical characteristics of the solar cells manufactured in n-type solar grade silicon are highly affected by the number of high-temperature thermal steps. The maximum efficiency of solar cells with emitter formed by BBr3 was 12.7%. The open circuit voltage values of solar cells with selective emitter were less than 560 mV, indicating that deterioration of the melting region by the laser radiation occurs, and the best solar cell achieved 11.6% efficiency. In general, devices with homogeneous emitter formed by spin-on showed higher efficiencies compared to the others, reaching 14.3% for solar cells with front grid formed with the PV3N1 metal paste. The TiO2 AR coatings deposited by APCVD and with the annealing at temperature of 400 ?C res ults in surface passivation, increasing the efficiency of the devices to 0.5% (absolute), which does not occur in AR coatings deposited by evaporation. / A ind?stria de c?lulas solares est? baseada na fabrica??o de dispositivos com estrutura n+pp+, com emissor de f?sforo e campo retrodifusor de alum?nio. Estudos mostram que a exposi??o ? radia??o solar pode causar a degrada??o das caracter?sticas el?tricas destes dispositivos, o que n?o ocorre em c?lulas solares fabricadas em sil?cio tipo n. Al?m disto, o sil?cio tipo n possui maior tempo de vida dos portadores de carga minorit?rios e ? menos afetado pela presen?a de impurezas quando comparado ao sil?cio tipo p. Com o objetivo de desenvolver c?lulas solares p+nn+, processos experimentais de fabrica??o foram realizados para dispositivos com emissor homog?neo, obtido a partir de BBr3 e dopantes depositados por spinon, emissor seletivo formado por radia??o laser e deposi??o de filmes antirreflexo (AR) por evapora??o e deposi??o qu?mica em fase vapor (APCVD). Em c?lulas solares com emissor homog?neo formado por BBr3 foi observado que a oxida??o seguida de recozimento a 400 ?C com forming gas proporciona uma m?nima passiva??o de superf?cie. Observou-se que as caracter?sticas el?tricas das c?lulas fabricadas em sil?cio grau solar tipo n s?o altamente afetadas pelo n?mero de passos t?rmicos de alta temperatura. A efici?ncia m?xima obtida em dispositivos com emissor formado por BBr3 foi de 12,7%. Os valores de tens?o de circuito aberto das c?lulas com emissores seletivos foram inferiores a 560 mV, indicando uma deteriora??o na regi?o fundida pela radia??o laser, e a melhor c?lula solar atingiu 11,6% de efici?ncia. Em geral, os dispositivos com emissores homog?neos formados por spin-on apresentaram efici?ncias superiores em rela??o aos demais, atingindo 14,3% com metaliza??o frontal com a pasta met?lica PV3N1. Filmes AR de TiO2 depositados por APCVD e submetidos ao recozimento em temperaturas da ordem de 400 ?C passivam a superf?cie, aumentando a efici ?ncia dos dispositivos em at? 0,5% (absoluto), o que n?o ocorre em filmes AR depositados por evapora??o.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2017-03-14T17:19:33Z No. of bitstreams: 1 DIS_RICARDO_AUGUSTO_ZANOTTO_RAZERA_COMPLETO.pdf: 2671041 bytes, checksum: f1125678bbb77f283914b17e91493182 (MD5) / Made available in DSpace on 2017-03-14T17:19:33Z (GMT). No. of bitstreams: 1 DIS_RICARDO_AUGUSTO_ZANOTTO_RAZERA_COMPLETO.pdf: 2671041 bytes, checksum: f1125678bbb77f283914b17e91493182 (MD5) Previous issue date: 2017-01-11 / The passivation of silicon solar cell surfaces is important for reducing the recombination rate of electron-hole pairs and, consequently, for improving efficiency. The goal of this work was to analyze the passivation quality obtained with thermal oxidation of solar grade silicon wafers and of solar cells with type p base and selective back surface field, producing thin films of SiO2. First, the dependence of minority carrier lifetime on oxidation time and temperature with and without the addition of chlorine was analyzed. I-V curves and spectral response measurements were conducted to determine the influence of oxidation parameters on the solar cells electrical characteristics. The results related to the oxidation furnace cleaning showed that introducing chlorine during oxidation it was possible to avoid the decline of minority carrier lifetime for silicon of Czochralski type and temperatures higher than 1000 ?C. As regarded to the oxide passivation, it was observed that the effective minority carrier lifetime increases for thicker oxides. The oxidation time and temperature that resulted in the highest efficiencies were 45 min and 800 ?C, resulting in oxide thicknesses on the front and back surfaces of 53 nm and 10 nm, respectively. The best solar cell with selective back surface field and SiO2 passivation presented Jsc = 36.0 mA/cm2, Voc = 598.6 mV and FF = 0.777, corresponding to an efficiency of 16.8 %. / A passiva??o das superf?cies de c?lulas solares ? importante para a redu??o da taxa de recombina??o de pares el?tron-lacuna e, consequentemente, para o aumento de efici?ncia. O objetivo deste trabalho foi analisar a qualidade da passiva??o obtida com oxida??o t?rmica de l?minas de sil?cio grau solar e c?lulas solares com base p e campo retrodifusor seletivo, produzindo filmes finos de SiO2. Primeiramente, foi analisada a depend?ncia do tempo de vida dos portadores de carga minorit?rios com o tempo e temperatura de oxida??o para oxida??es com e sem adi??o de cloro. Medidas de curva I-V e resposta espectral foram realizadas para determinar a influ?ncia dos par?metros de oxida??o nas caracter?sticas el?tricas de c?lulas solares. Os resultados relacionados ? limpeza do tubo de oxida??o mostraram que a introdu??o de cloro durante a oxida??o foi capaz de evitar a diminui??o do tempo de vida dos portadores minorit?rios para l?minas de sil?cio tipo Czochralski para temperaturas de processo maiores que 1000 ?C. Em rela??o a passiva??o atribu?da ao ?xido, foi observado que o tempo de vida efetivo dos portadores minorit?rios aumenta para ?xidos mais espessos. O tempo e a temperatura de oxida??o que resultaram em maiores efici?ncias foram de 45 min e 800 ?C, apresentando uma camada de SiO2 nas faces frontal e posterior de 53 nm e 10 nm, respectivamente. A melhor c?lula solar com campo retrodifusor seletivo e com passiva??o de SiO2 apresentou Jsc = 36,0 mA/cm2, Voc = 598,6 mV e FF = 0,777, correspondendo a uma efici?ncia de 16,8 %.

No description available.

This diploma thesis was based on the main theme of Competitive advantage. The theoretical part of this thesis is concerned with concepts of competition, competitiveness and competitive advantage. Next part is based on analysis of outside surroundings where are specified the main methods of analysing company surroundings. The names of the methods are PEST analysis, SWOT analysis and Porter five forces. In the last part of theoretical thesis are explained types of innovation and innovation process. The conceptual part of the diploma thesis is related to company Snag s.r.o. and its evolution in two periods. The aim of these analysis where to name the main elements with the biggest impact. In the end of the first period was made a decision about new company strategy. According to the new company strategy there was effected innovation process that created new product for selling. This innovation has had crucial market to the competitive position of the company. The implementation of the new strategy has started new periond of growing the company.

No description available.

Made available in DSpace on 2016-08-29T15:36:58Z (GMT). No. of bitstreams: 1 tese_5255_.pdf: 759125 bytes, checksum: 4561c3eeddc95a3b77ac4771d2fb20ee (MD5) Previous issue date: 2011-12-19 / RIBEIRO, Paulo Henrique. Matéria orgânica e atributos químicos em solo de Tabuleiros sob diferentes coberturas vegetais. 2011. Dissertação (Mestrado em Ciências Florestais) Universidade Federal do Espírito Santo, Alegre ES. Orientador: Prof. Dr. Renato Ribeiro Passos. Coorientador: Prof. Dr. Felipe Vaz Andrade. Coorientador: Prof. Dr. Hugo Alberto Ruiz. A substituição da vegetação nativa por cultivos agrícolas e florestais resulta em modificações nos atributos do solo. Neste trabalho objetivou-se avaliar a dinâmica dos atributos de um Latossolo Amarelo em diferentes coberturas vegetais nos Tabuleiros Costeiros. As amostras de solo foram coletadas nas profundidades de 0-10, 10-20 e 20-40 cm em junho de 2011, em Sooretama, ES, considerando quatro coberturas vegetais: mata nativa, café conilon em monocultivo, café conilon em consórcio com cedro e cacau em consórcio com cedro. O delineamento experimental utilizado foi o inteiramente casualizado em parcelas subdivididas com três repetições. Foram avaliados os seguintes atributos do solo: pH em água; fósforo disponível; potássio, cálcio e magnésio trocáveis; alumínio trocável; acidez potencial; soma de bases; capacidade de troca de cátions efetiva e potencial; saturação por bases e por alumínio; carbono orgânico total (COT); nitrogênio total (NT); carbono orgânico solúvel em água (CSA); relações COT/NT e COT/CSA; matéria orgânica leve; e estoques de COT e NT. Avaliou-se também a serapilheira, e com base na produção de matéria seca e nos teores de nutrientes da mesma, calcularam-se os acúmulos de cada nutriente. Os resultados obtidos foram submetidos à análise da variância e os contrastes comparadas pelo teste F a 1, 5 e a 20 % de probabilidade. Os resultados experimentais mostraram que os sistemas de uso e manejo comportaram-se de forma diferenciada para determinados atributos do solo. A mata foi a cobertura que mais favoreceu o estoque de carbono e nitrogênio no sistema, demonstrado pelos maiores teores de COT e NT, carbono solúvel em água, matéria orgânica leve e acúmulo de serapilheira. Os cultivos agrícolas demonstraram potencial de estocar carbono e nitrogênio no solo. As condições químicas do solo mais adequadas para o desenvolvimento de plantas foram encontradas no solo sob cafeeiro em monocultivo. A elevada acidez, altos níveis de alumínio e baixa disponibilidade de nutrientes no solo sob mata refletiram sua condição natural. Os consórcios agroflorestais apresentaram condição similar para a fertilidade do solo. No entanto, diferenciaram quanto ao acúmulo de serapilheira e nutrientes na serapilheira. Palavras-chave: estoque de carbono, fertilidade do solo, café conilon, consórcio agroflorestal

Tato práce se zaměřuje na téma konkurenceschopnosti. Jejím hlavním cílem je podrobit zkoumání strategické konkurenční chování firem a dále identifikovat a analyzovat faktory ovlivňující jejich konkurenceschopnost. V první části práce jsou představeny teoretické přístupy a analytické nástroje sloužící k mapování systémového okolí a konkurence firmy. V kontextu konkurence jsou zkoumány především inovace a strategická partnerství. Ve druhé části jsou tyto teoretické přístupy aplikovány na firmu Medtronic, za účelem zhodnocení firmy z hlediska jejího strategického konkurenčního chování a doporučení dalšího vývoje. Na základě této aplikace je poté zhodnocena využitelnost teoretických modelů v praxi.

This diploma thesis deals with the implementation of SIL and PIL simulation for the microcontroller Aurix TriCore TC277D performed in the Matlab Simulink. The realization of the simulation represents, among other things, the implementation of the simulated model into the microcontroller, as well as the creation of an interface for the communication of the microcontroller with the Matlab Simulink. The accuracy of SIL and PIL simulations was verified by comparing the simulated waveforms from the simulation in Simulink. The simulated model used a thermal model of a car cabin created in the previous bachelor's thesis of the author of this diploma thesis. The model in TC277D, as well as the configuration for SIL / PIL is created for use with the C programming language. The work also includes instructions according to which the model and configuration can be modified so that the simulations can be performed on any device containing the necessary software. From the comparison of the simulated data is it clear that the created configuration can be used for SIL or PIL simulation.

The theme of this diploma thesis is aeration and dedusting of storage silos. The problematics in this thesis is industrial de-dusting of storage silos during their aeration. The thesis is divided into a theoretical part, which contains a general description of the procedure for the design of industrial dedusting and a practical part, in which a real proposal for solving the problem is created. An analysis of current state of the selected company was done in this thesis. A design of the aeration and dedusting of the storage silos of this company was compiled. The proposed solution was implemented into the company premises using 3D software. The investment costs of the design implementation and the economy of the operation were evaluated at the end of this thesis.

No description available.