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Blind Adaptive DS-CDMA Receivers with Sliding Window Constant Modulus GSC-RLS Algorithm Based on Min/Max Criterion for Time-Variant ChannelsChang, Shih-chi 26 July 2006 (has links)
The code division multiple access (CDMA) system implemented by the direct-sequence (DS) spread spectrum (SS) technique is one of the most promising multiplexing technologies for wireless communications services. The SS communication adopts a technique of using much wider bandwidth necessary to transmit the information over the channel. In the DS-CDMA system, due to the inherent structure interference, referred to as the multiple access interference (MAI), the system performance might degrade. Next, for DS-CDMA systems over frequency-selective fading channels, the effect of inter symbol interference (ISI) will exist, such that a multiuser RAKE receiver has to be employed to combat the ISI as well as MAI. Since, in practical wireless communication environment, there may have several communication systems operated in the same area at the same time. In this thesis, we consider the environment of DS-CDMA systems, where the asynchronous narrow band interference (NBI) due to other systems is joined suddenly to the CDMA system. In general, when a system works in a stable state with adaptive detectors, a suddenly joined NBI signal will cause the system performance to be crash down. Under such circumstance, the existing conventional adaptive RAKE detectors may not be able to track well for the rapidly sudden changing NBI associated with the problems of ISI and MAI.
It is known that the adaptive filtering algorithms, based on the sliding window linear constrained recursive least squares (SW LC-RLS), is very attractive to a violent changing environment. The main concern of this thesis is to propose a novel sliding window constant modulus RLS (SW CM-RLS) algorithm, based on the Min/max criterion, to deal with the NBI for DS-CDMA system over multipath channels. For simplicity and having less system complexity the generalized side-lobe canceller (GSC) structure is employed, and is referred to as the SW CM-GSC-RLS algorithm. The aim of the SW CM-GSC-RLS algorithm is used to alleviate the effect of NBI. It has the advantages of having faster convergence property and tracking ability, and can be applied to the environment in which the NBI is suddenly joined to the system under the effect of channel mismatch to achieve desired performance. At the end of this thesis, we extend the idea of the proposed algorithm to the space-time DS-CDMA RAKE receiver, in which the adaptive beamformer with temporal domain DS-CDMA receiver is employed. Via computer simulation results, we show that our new proposed schemes outperform the conventional CM GSC-RLS algorithm as well as the GSC-RLS algorithm (the so-called LCMV approach), in terms of mean square error of estimating channel impulse response, output signal to interference plus noise ratio and bit-error-rate.
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Mikro- und makroskopische Eigenschaften von statistisch und nicht-statistisch aufgebauten Copolymeren / Radikalische Polymerisationen in einem weiten Zustandsbereich bis hin zu hohen Drücken und Temperaturen / Properties of random and non-random copolymers / poly(ethylene-co-methacrylic acid): synthesis and characterizationSteisel, Björn 01 November 2007 (has links)
No description available.
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Algoritmos e arquiteturas para o desenvolvimento de sistemas computacionais / Algorithms and architectures to the development of computational systemsCarro, Luigi January 1996 (has links)
Este trabalho trata de arquiteturas e algoritmos para o desenvolvimento de sistemas computacionais. Tais sistemas são constituídos de um microprocessador (específico ou comercialmente disponível), de seu conjunto de programas e de um HW dedicado que será utilizado para otimização do sistema. O objetivo principal desta tese é demonstrar que, presentemente, a linha divisória entre HW e SW e cada vez mais tênue, e a transição entre um e outro pode ser feita de maneira suave pelo projetista de sistemas, na busca de um ponto ótimo no balanço entre custo e desempenho. Apresenta-se em seqüência o ambiente de CAD, a classificação de rotinas e os métodos de otimização tendo em vista esta classificação para o aumento de desempenho de sistemas computacionais. A seguir são apresentadas técnicas para processadores dedicados de arquitetura Risc, visando a otimização de certos tipos de programas. Os resultados de aceleração são apresentados para um conjunto de exemplos. Tendo em vista o mercado nacional de eletrônica, fortemente baseado em microcontroladores, estudam-se e mostram-se possibilidades de otimização e integração de sistemas baseados em tais processadores, assim como a aplicabilidade das mesmas técnicas para processadores dedicados. A viabilidade técnica desta realização é discutida através de exemplos baseados em aplicações reais. Finalmente, a validação de sistemas computacionais, em especial aqueles trabalhados nesta tese, é discutida. / This work discusses architectures and algorithms for the development of computational systems, which are based on a microprocessor (custom or off-the-shelf), the set of application programs and a dedicated HW, used to increase the performance of the whole system. The goal of this work is to show that, nowadays, the division line between SW and HW is smooth, and the transition from one to the other can be achieved by the system designer using a specific CAD in order to obtain a trade-off between cost and performance. The CAD environment is presented, followed by routine classification and optimization methods based on the former classification to increase the performance of the system. Techniques devoted to systems based on dedicated Risc processors are showed next, to optimize certain type of programs. Positive results are shown for a set of examples. Since the Brazilian electronics market is strongly based on microcontrollers, the study and results of optimization techniques regarding this type of systems are also presented. The same techniques can be applied to dedicated processors as well. Results of this proposal are obtained for a set of real world examples. The last topic of this work regards the validation of computational systems, mainly those presented throughout this work.
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Algoritmos e arquiteturas para o desenvolvimento de sistemas computacionais / Algorithms and architectures to the development of computational systemsCarro, Luigi January 1996 (has links)
Este trabalho trata de arquiteturas e algoritmos para o desenvolvimento de sistemas computacionais. Tais sistemas são constituídos de um microprocessador (específico ou comercialmente disponível), de seu conjunto de programas e de um HW dedicado que será utilizado para otimização do sistema. O objetivo principal desta tese é demonstrar que, presentemente, a linha divisória entre HW e SW e cada vez mais tênue, e a transição entre um e outro pode ser feita de maneira suave pelo projetista de sistemas, na busca de um ponto ótimo no balanço entre custo e desempenho. Apresenta-se em seqüência o ambiente de CAD, a classificação de rotinas e os métodos de otimização tendo em vista esta classificação para o aumento de desempenho de sistemas computacionais. A seguir são apresentadas técnicas para processadores dedicados de arquitetura Risc, visando a otimização de certos tipos de programas. Os resultados de aceleração são apresentados para um conjunto de exemplos. Tendo em vista o mercado nacional de eletrônica, fortemente baseado em microcontroladores, estudam-se e mostram-se possibilidades de otimização e integração de sistemas baseados em tais processadores, assim como a aplicabilidade das mesmas técnicas para processadores dedicados. A viabilidade técnica desta realização é discutida através de exemplos baseados em aplicações reais. Finalmente, a validação de sistemas computacionais, em especial aqueles trabalhados nesta tese, é discutida. / This work discusses architectures and algorithms for the development of computational systems, which are based on a microprocessor (custom or off-the-shelf), the set of application programs and a dedicated HW, used to increase the performance of the whole system. The goal of this work is to show that, nowadays, the division line between SW and HW is smooth, and the transition from one to the other can be achieved by the system designer using a specific CAD in order to obtain a trade-off between cost and performance. The CAD environment is presented, followed by routine classification and optimization methods based on the former classification to increase the performance of the system. Techniques devoted to systems based on dedicated Risc processors are showed next, to optimize certain type of programs. Positive results are shown for a set of examples. Since the Brazilian electronics market is strongly based on microcontrollers, the study and results of optimization techniques regarding this type of systems are also presented. The same techniques can be applied to dedicated processors as well. Results of this proposal are obtained for a set of real world examples. The last topic of this work regards the validation of computational systems, mainly those presented throughout this work.
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A contribuição do Seis Sigma para a melhoria dos processos de software. / A Six Sigma contribution for software process improvement.Antonio Carlos Tonini 21 September 2006 (has links)
Uma das grandes dificuldades do desenvolvimento de software é adequar, de forma sistemática, os esforços na resolução de problemas e nas melhorias dos processos internos aos objetivos do negócio. O Seis Sigma é uma metodologia estruturada que incrementa a qualidade dos processos e o alinhamento com as estratégias empresariais, proporcionando altos ganhos financeiros para quem o utiliza. Surgido inicialmente na manufatura, o Seis Sigma vem sendo aplicado também noutros setores. No desenvolvimento de software, o seu uso é ainda restrito, mas há indícios de que possa ser utilizado com o mesmo sucesso. O objetivo desta dissertação de mestrado é propor um roteiro específico para a implementação do Seis Sigma nas organizações desenvolvedoras de software. Além do levantamento teórico, foi realizado um estudo de casos múltiplos para analisar as razões da sua adoção, as modalidades de seu uso, os seus benefícios e as suas limitações para os processos de software. Os resultados observados mostram que o Seis Sigma pode ser aplicado total ou parcialmente na melhoria dos processos de software. Além disso, é necessário alguma customização nos processos do Seis Sigma convencional, uma vez que os projetos de melhoria podem estar orientados para novos produtos, novos clientes ou, ainda, que os trabalhos de desenvolvimento fiquem a cargo de novas equipes, que muitas vezes são terceirizadas. O trabalho conclui que o Seis Sigma pode contribuir efetivamente para a melhoria dos processos de software, independentemente da organização objetivar níveis superiores de maturidade. O estudo sugere também um roteiro específico, chamado SW-DMAIC, para a aplicação do Seis Sigma em empresas desenvolvedoras de software. Este roteiro é composto por três etapas: implementação da filosofia do Seis Sigma, reciclagem desta filosofia, quando necessário e execução de projetos específicos. / Aligning sistematically efforts to solve problems and improve the software process with business goals is one of the challenges of software development. Six Sigma is a structured methodology that increases the process quality and aligning with enterprise strategies, providing high financial returns for those who uses it. Firstly applied in manufacturing companies, Six Sigma has been applied in other sectors too. It is not widely used in the software companies yet, but there are already some successful cases. The main objective of this master degree dissertation is to propose a specific roadmap for the Six Sigma application at software companies. Besides the theoretical research, it is accomplished a multiple case study to analyze the adoption reasons, the modalities of the use, the benefits and the limitations of Six Sigma for the software processes. The observed results show that Six Sigma could be applied totally or partially for software process improvement. Therefore it is necessary some tayloring in the Six Sigma processes, because improvement projects could refer for new products or new customers or some of the development work is in charge of new teams, specially when they are a outsoursing. The work has concluded that Six Sigma could contribute indeed to software process improvement, independently the enterprise is going to reach higher level maturity. This study suggests also a specific three-stage-roadmap, called SW-DMAIC, for the Six Sigma application at software companies containing processes for implementation of Six Sigma?s philosophy, recycling this philosophy when it?s necessary and, execution of specific Six Sigma projects.
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Algoritmos e arquiteturas para o desenvolvimento de sistemas computacionais / Algorithms and architectures to the development of computational systemsCarro, Luigi January 1996 (has links)
Este trabalho trata de arquiteturas e algoritmos para o desenvolvimento de sistemas computacionais. Tais sistemas são constituídos de um microprocessador (específico ou comercialmente disponível), de seu conjunto de programas e de um HW dedicado que será utilizado para otimização do sistema. O objetivo principal desta tese é demonstrar que, presentemente, a linha divisória entre HW e SW e cada vez mais tênue, e a transição entre um e outro pode ser feita de maneira suave pelo projetista de sistemas, na busca de um ponto ótimo no balanço entre custo e desempenho. Apresenta-se em seqüência o ambiente de CAD, a classificação de rotinas e os métodos de otimização tendo em vista esta classificação para o aumento de desempenho de sistemas computacionais. A seguir são apresentadas técnicas para processadores dedicados de arquitetura Risc, visando a otimização de certos tipos de programas. Os resultados de aceleração são apresentados para um conjunto de exemplos. Tendo em vista o mercado nacional de eletrônica, fortemente baseado em microcontroladores, estudam-se e mostram-se possibilidades de otimização e integração de sistemas baseados em tais processadores, assim como a aplicabilidade das mesmas técnicas para processadores dedicados. A viabilidade técnica desta realização é discutida através de exemplos baseados em aplicações reais. Finalmente, a validação de sistemas computacionais, em especial aqueles trabalhados nesta tese, é discutida. / This work discusses architectures and algorithms for the development of computational systems, which are based on a microprocessor (custom or off-the-shelf), the set of application programs and a dedicated HW, used to increase the performance of the whole system. The goal of this work is to show that, nowadays, the division line between SW and HW is smooth, and the transition from one to the other can be achieved by the system designer using a specific CAD in order to obtain a trade-off between cost and performance. The CAD environment is presented, followed by routine classification and optimization methods based on the former classification to increase the performance of the system. Techniques devoted to systems based on dedicated Risc processors are showed next, to optimize certain type of programs. Positive results are shown for a set of examples. Since the Brazilian electronics market is strongly based on microcontrollers, the study and results of optimization techniques regarding this type of systems are also presented. The same techniques can be applied to dedicated processors as well. Results of this proposal are obtained for a set of real world examples. The last topic of this work regards the validation of computational systems, mainly those presented throughout this work.
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Rekonstrukce předpjatého železničního mostu / The reconstruction of the prestressed railway bridgeMacková, Lucie January 2014 (has links)
Diploma thesis describes the design of main structure reinforcement of the railway bridge ,,Gagarin’’ in the 5,872 km of route Český Těšín – Ostrava Kunčice. Reinforcement is achieved by combination of composite slab-shaped channel with the continuous gravel ballast and free additional prestressing cables. There are 3 variants for which the design and assessment of main structure is performed. Evaluation of the options is performed on basis of calculations. There are made additional calculations and drawings for best variant.
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Ladicí nástroj generických simulátorů mikroprocesorů / Debugger for Generic Microprocessor SimulatorsWilczák, Milan January 2010 (has links)
Application specific instruction set processors become part of every day life although it's not always visible at first sight. During their development it's needed to somehow describe their architecture, instruction set and behavior. To make their developement worth, it's necessary to be able to create applications for these processors and during application development errors are always made. Debuggers serve to discover and help fixing them. This paper summarises some basic information to debugger development and describes implementation for processors created using the Lissom project.
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Post-IR IRSL dating of K-feldspar from Loess at Lowland Point, SW England : Developing a Chronology for Past Climate Records / Post-IR IRSL datering av kalifältspat från löss vid Lowland Point, sydvästra England : utveckling av kronologi för tidigare klimatregisterTörnqvist, Elin January 2022 (has links)
Loess deposits are terrestrial clastic sediments derived from aeolian deposition. Loess is transported in periglacial conditions and was mainly deposited in cold environments around glaciers during the Quaternary period. To be able to understand and interpret past climate and how it was changing, loess deposits can be used as an indicator for example wind circulation and dustiness in the atmosphere. However, good independent chronological control is essential for using loess as a past climate archive. This study has examined loess from Lowland Point in the southwest of England. The loess at Lowland Point is relatively thin at 180 cm compared with more studied loess deposits further east on continental Europe. To be able to date the k-feldspar mineral grains from the loess deposit at Lowland Point, two values should be constrained for each sample: the equivalent dose (DE), a quantitative factor of the amount of energy accumulated by the mineral grain during burial from ionising radiation, and the dose rate (DR), a rate of ionising radiation absorbed from the surrounding environment per year. By using the post infrared-infrared stimulated luminescence (post-IR IRSL) method, the DE values were obtained, and by examine radioactive isotopes in the samples, the DR values were attained. The results of each average age per sample depth was then identified and the loess deposit could be determined to the age about 10.8-22.4 ka, which is suggested to have been deposited by meltwater from the British Irish Ice Sheet and permafrost. / Lössjordar är avlagringar av markbundna klastiska sediment härledda från eolisk deposition och transporteras under periglaciala förhållanden för att huvudsakligen deponeras i kalla miljöer runt glaciärer under kvartärperioden. För att kunna förstå och tolka tidigare klimat och hur det förändrades kan lössavlagringar användas som en indikation över till exempel vindcirkulation och dammighet i atmosfären. Denna studie har undersökt löss från Lowland Point i sydvästra England. Lössen vid Lowland Point är relativt tunn, med en tjocklek på 180 cm, jämfört med mer studerade lössjordar. För att kunna datera kalifältspat från lössjorden vid Lowland Point var förhållandet mellan två komponenter av betydelse; ekvivalentdosen (DE), en kvantitativ faktor för den mängd energi som mineralkornet ackumulerar vid sedimentering, och doshastigheten (DR), en hastighet av den mängd energi som absorberas i den omgivande miljön per år. Genom att använda metoden post infraröd-infraröd stimulerad luminescens (post-IR IRSL) erhölls DE-värden och genom att undersöka radioaktiva isotoper i proverna hittades DR-värden. Resultaten av varje medelålder per provdjup identifierades sedan och lössavlagringen kunde bestämmas till en ålder av cirka 10,8–22,4 ka, vilket indikerar en möjlig avsättning av smältvatten från det brittiska irländska istäcket och permafrost.
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Does blue light restore human epidermal barrier function via activation of Opsin during cutaneous wound healing?Castellano-Pellicena, Irene, Uzunbajakava, N.E., Mignon, Charles, Raafs, B., Botchkarev, Vladimir A., Thornton, M. Julie 31 August 2018 (has links)
Yes / Background and Objective
Visible light has beneficial effects on cutaneous wound healing, but the role of potential photoreceptors in human skin is unknown. In addition, inconsistency in the parameters of blue and red light‐based therapies for skin conditions makes interpretation difficult. Red light can activate cytochrome c oxidase and has been proposed as a wound healing therapy. UV‐blue light can activate Opsin 1‐SW, Opsin 2, Opsin 3, Opsin 4, and Opsin 5 receptors, triggering biological responses, but their role in human skin physiology is unclear.
Materials and Methods
Localization of Opsins was analyzed in situ in human skin derived from face and abdomen by immunohistochemistry. An ex vivo human skin wound healing model was established and expression of Opsins confirmed by immunohistochemistry. The rate of wound closure was quantitated after irradiation with blue and red light and mRNA was extracted from the regenerating epithelial tongue by laser micro‐dissection to detect changes in Opsin 3 (OPN3) expression. Retention of the expression of Opsins in primary cultures of human epidermal keratinocytes and dermal fibroblasts was confirmed by qRT‐PCR and immunocytochemistry. Modulation of metabolic activity by visible light was studied. Furthermore, migration in a scratch‐wound assay, DNA synthesis and differentiation of epidermal keratinocytes was established following irradiation with blue light. A role for OPN3 in keratinocytes was investigated by gene silencing.
Results
Opsin receptors (OPN1‐SW, 3 and 5) were similarly localized in the epidermis of human facial and abdominal skin in situ. Corresponding expression was confirmed in the regenerating epithelial tongue of ex vivo wounds after 2 days in culture, and irradiation with blue light stimulated wound closure, with a corresponding increase in OPN3 expression. Expression of Opsins was retained in primary cultures of epidermal keratinocytes and dermal fibroblasts. Both blue and red light stimulated the metabolic activity of cultured keratinocytes. Low levels of blue light reduced DNA synthesis and stimulated differentiation of keratinocytes. While low levels of blue light did not alter keratinocyte migration in a scratch wound assay, higher levels inhibited migration. Gene silencing of OPN3 in keratinocytes was effective (87% reduction). The rate of DNA synthesis in OPN3 knockdown keratinocytes did not change following irradiation with blue light, however, the level of differentiation was decreased.
Conclusions
Opsins are expressed in the epidermis and dermis of human skin and in the newly regenerating epidermis following wounding. An increase in OPN3 expression in the epithelial tongue may be a potential mechanism for the stimulation of wound closure by blue light. Since keratinocytes and fibroblasts retain their expression of Opsins in culture, they provide a good model to investigate the mechanism of blue light in wound healing responses. Knockdown of OPN3 led to a reduction in early differentiation of keratinocytes following irradiation with blue light, suggesting OPN3 is required for restoration of the barrier function. Understanding the function and relationship of different photoreceptors and their response to specific light parameters will lead to the development of reliable light‐based therapies for cutaneous wound healing. / European Commission 7th Framework Programme for Research and Technical Development - Marie Curie Innovative Training Networks (ITN), Grant agreement no.: 607886
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