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Abrahamsson, Sebastian, and Markus Råbe. "An FPGA implementation of a modulator for digital terrestrial television according to the DTMB standard." Thesis, Linköping University, Department of Electrical Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-55538.
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The increasing data rates in digital television networks increase the demands on data capacity of the current transmission channels. Through new standards, the capacity of exisiting channels is increased with new methods of error correction coding and modulation.
This thesis presents the design and implementation of a modulator for transmission of digital terrestrial television according to the Chinese DTMB standard.
The system is written in VHDL and is intended for implementation on an FPGA.
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Abyaneh, Hossein Askarian. "Assessment of IDMT and distance relay settings." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332331.
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Ngimbwa, Peter Cosmas. "An Irrigation Decision Support Tool (IDST) for Smallholdings in Tanzania." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461171005.
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Du, Guangli. "Implementation of the SuperPave IDT analysis procedure." Thesis, KTH, Väg- och banteknik (stängd 20110301), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-52983.
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Cracking is one of the most severe distress modes of asphaltpavements. Thus characterising the fracture resistance properties of asphaltmixtures is the key issue for improving the performance relatedmixture design. The present master thesis project addresses the implementationof the theoretical framework, which is used to characterise thefracture resistance of mixtures based on the SuperPave indirect tensiletest (IDT). An open source Matlab-based software for analysing resilientmodulus, Poisson’s ratio, creep parameters and fracture resistance parametershas been developed. The software analyses the the IDT results, toestimate mixture’s fracture resistance based on hot mix asphalt FractureMechanics. Predictions form the field specimens concerning the fractureresistance obtained from IDT are compared with observed field performance.
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Bista, Sulabh. "Assessing the Physical Security of IDFs with PSATool: a Case Study." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etd/2605.
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PSATool is a checklist-based, web-based application for assessing the physical security of Intermediate Distribution Frameworks. IDFs, or wiring closets, are an integral if often neglected component of information security. Earlier work by Timbs (2013) identified 52 IDF-related security requirements based on federal and international standards for physical security. PSATool refines Timbs’ prototype application for IDF assessment, extending it with support for mobile-device-based data entry.
PSATool was used to assess 25 IDFs at a regional university, a college and a manufacturing corporation, with an average of 9 minutes per assessment. Network managers and assessors involved in the assessments characterized PSATool as suitable for creating assessments, usable by IT department personnel, and accurate, in terms of its characterizations of IDF status.
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Halvarsson, Evelin, and Amanda Karsson. "Evidensbaseradeomvårdnadsbehov som påverkar livskvaliteten hos patienter idet palliativa skedet : En systematisk litteraturstudie." Thesis, Högskolan Dalarna, Omvårdnad, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:du-4420.
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Arabackyj, Marc [Verfasser]. "Steigerung der Qualität des Fertigungstests integrierter Schaltungen durch IDDT-Verfahren / Marc Arabackyj." München : Verlag Dr. Hut, 2012. http://d-nb.info/1025821475/34.
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Song, Kibong. "Development of an Information Base Tool for IDT Research." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/52590.
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Identifying and articulating a research topic and related problems are important processes for novice researchers. However, some novice researchers have trouble in these processes due to their low domain knowledge, low structural knowledge, insufficient metacognition, or insufficient information access skills. This study addressed these problems by developing an information base tool using strategies and tools investigated by previous studies. The tool includes conceptual modeling, guided search, experimental variables and relationships examination, note-taking, suggestion, file import, and review features. The tool was populated with relevant information to permit testing and formative evaluation by novice researchers. Expert reviewers evaluated the effects of each feature of the tool on scaffolding individuals who have low domain knowledge or low structural knowledge and supplementing individuals who have insufficient metacognition or insufficient information access skills. The reviewers commonly agreed that specific components of the tool would be effective in scaffolding individuals who have low domain knowledge or low structural knowledge, or supplementing individuals who have insufficient information access skills.Ph. D.
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Estêvão, Carlos Miguel da Silva Coelho Pinheiro. "O IDT, IP no contexto do NPM e do PRACE." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12316.
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Mestrado em Administração e Gestão PúblicaO estudo reflete sobre o IDT,IP, organismo público que tinha como missão operacionalizar as políticas públicas de luta contra as drogas, lícitas e ilícitas, e as dependências. Neste sentido, o objetivo do trabalho visa avaliar os impactos que podem ser observados no IDT,IP resultantes das reformas administrativas influenciadas pelo NPM ocorridas na Administração Pública portuguesa, especificamente pelo PRACE, e pelas opções de Políticas Públicas de luta contra as drogas assumidas por Portugal ao longo da primeira década do século XXI. Tendo em conta o objetivo definido anteriormente optámos por realizar um estudo comparativo entre o IDT e o IDT,IP, investigando, para cada um deles, os impactos decorrentes das três dimensões mencionadas. Para isso foi necessário, previamente, contextualizar e fundamentar as três dimensões. No final da investigação concluímos que o IDT,IP é um organismo público onde os impactos decorrentes do paradigma do NPM, do PRACE e das opções de Política Pública das Drogas se evidenciam claramente.
The study reflects on the IDT,IP, a public structure whose mission was to operationalize public policies to combat drugs, licit and illicit, and dependencies. In this sense the purpose of the study is to evaluate the impacts that can be observed in the IDT,IP resulting from the administrative reforms influenced by NPM occurred in the Portuguese Administration, more specifically by the PRACE, and the Public Policy options assumed by Portugal throughout the first decade of the twenty-first century. Taking into account the obective of the investigation, we developed a comparative study between the IDT and the IDT,IP, analysing, for each of them, the impacts resulting from the three mentioned subjects. This required a previous contextualization and explanation of the three concepts. At the end of the investigation it is possible to understand that the IDT,IP is a public organisation where the impacts of the NPM paradigm, the PRACE and the Drugs Public Policy options is clearly evident.
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Torres, Quintana Eduardo Andrés. "Determinación de curvas IDF en la Región de Antofagasta, Chile." Tesis, Universidad de Chile, 2016. http://repositorio.uchile.cl/handle/2250/138960.
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Ingeniero CivilEn la región de Antofagasta, ubicada en el extremo norte de Chile, se encuentra una de las zonas más áridas de Sudamérica. La cantidad de ríos y lagos que se ubican en la zona son escasos, y es por esto que la recolección y utilización de aguas no saladas es dificultosa, a la vez que cualquier tipo de proyecto que tenga que ver con hidráulica el recurso hídrico. Sumado a lo anterior, la información hidrológica de la zona es escasa, debido a la baja cantidad de estaciones de medición disponible, con un extenso período continuo de tiempo, ya los pocos estudios actualizados realizados en la zona, siendo el Atlas de "Precipitaciones máximas 1, 2 y 3 días" (DGA 1991) el más actualizado en curvas IDF, lo cual no es adecuado para el diseño de obras hidráulicas en el año 2016, debido a que no incorpora los últimos 25 años de la historia climática de la zona. Por ello, los objetivos del trabajo de título aquí presente serán actualizar los coeficientes de duración y frecuencia, curvas IDF (Intensidad-Duración-Frecuencia) de Antofagasta y presentar isoyetas actualizadas de la II región de Chile. Se realizaron todos los procesos normales en el análisis de datos hidrológicos para distribuciones extremas, conducentes a obtener proyecciones acertadas de la precipitación en escalas de tiempo de 1 a 72 horas, para períodos de retorno entre 2 a 100 años. El proceso realizado se divide en 3 grandes secciones. Primero, la obtención de datos, la cual se realizó a partir de la información de precipitaciones diarias disponible en el Banco Nacional de Aguas y la Dirección Meteorológica de Chile (DMC) y, se incorpora la información de datos horarios de reanálisis de la NASA, y CISL RDA. . Segundo, Análisis de Frecuencia, donde se encontraron las distribuciones que mejor representaban a los datos obtenidos y a partir de estas, se obtuvieron los coeficientes de duración y frecuencia para cada estación. Tercero, la generación de isoyetas correspondientes a la precipitación de período de retorno de 10 años y duración de 1 día, y las curvas Intensidad-Duración-Frecuencia para cada localidad. Los resultados demuestran la utilidad del uso de datos de reanálisis, y que las tormentas en el extremo norte del país han variado entre un 3 a un 15% (tanto para coeficientes de duración como de frecuencia) para algunas zonas, e, incluso, hasta variaciones superiores al 30% (positivas o negativas) para otras en su intensidad promedio para sus diferentes duraciones y períodos de retorno, al igual que en sus valores de cantidad total precipitada por tormenta extrema. Se concluye que los resultados antiguos ya no son adecuados para el diseño de obras hidráulicas actuales Las curvas IDF y las isoyetas presentadas son suficientes por tanto para proyectos que utilicen de las precipitaciones en la región de Antofagasta.
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Pai, Cheng-Yu. "Design and evaluation of a data-dependent low-power 8 x 8 DCT/IDCT." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ59308.pdf.
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Anders, Jörg. "Java MPEG1-Player." Universitätsbibliothek Chemnitz, 2003. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200300738.
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Arabackyj, Marc [Verfasser], and Klaus [Akademischer Betreuer] Helmreich. "Steigerung der Qualität des Fertigungstests integrierter Schaltungen durch IDDT-Verfahren / Marc Arabackyj. Betreuer: Klaus Helmreich." Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2012. http://d-nb.info/1024198952/34.
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August, Nathaniel J. "On the Low Power Design of DCT and IDCT for Low Bit Rate Video Codecs." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/32125.
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Wireless video systems have applications in cellular videophones, surveillance systems, and mobile patrols. The design of a wireless video system must consider two important constraints: low bit rate and low power dissipation. The ITU-T H.263 video codec standard is suitable for low bit rate wireless video systems, however it is computationally intensive. Some of the most computationally intensive operations in H.263 are the Discrete Cosine Transform (DCT) and the Inverse Discrete Cosine Transform (IDCT), which perform spatial compression and decompression of the data.
In an ASIC implementation of H.263, the high computational complexity of the DCT and IDCT leads to high power dissipation of the blocks. Low power design of the DCT and IDCT is essential in a portable wireless video system. This paper examines low power design techniques for DCT and IDCT circuits applicable for low bit rate wireless video systems. Five low power techniques are applied to baseline reference DCT and IDCT circuits. The techniques include skipping low energy DCT input, skipping all-zero IDCT input, low precision constant multipliers, clock gating, and a low transition data path. Gate-level simulations characterize the effectiveness of each technique. The combination of all techniques reduces average power dissipation by 95% over the baseline reference DCT and IDCT blocks.Master of Science
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Castillo, Jean M. "Duration-rainfall intensity equations : study of IDF curves using local precipitation data /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1203570521&sid=23&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Vannah, Benjamin. "Integrated Data Fusion and Mining (IDFM) Technique for Monitoring Water Quality in Large and Small Lakes." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6028.
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Monitoring water quality on a near-real-time basis to address water resources management and public health concerns in coupled natural systems and the built environment is by no means an easy task. Furthermore, this emerging societal challenge will continue to grow, due to the ever-increasing anthropogenic impacts upon surface waters. For example, urban growth and agricultural operations have led to an influx of nutrients into surface waters stimulating harmful algal bloom formation, and stormwater runoff from urban areas contributes to the accumulation of total organic carbon (TOC) in surface waters. TOC in surface waters is a known precursor of disinfection byproducts in drinking water treatment, and microcystin is a potent hepatotoxin produced by the bacteria Microcystis, which can form expansive algal blooms in eutrophied lakes. Due to the ecological impacts and human health hazards posed by TOC and microcystin, it is imperative that municipal decision makers and water treatment plant operators are equipped with a rapid and economical means to track and measure these substances.
Remote sensing is an emergent solution for monitoring and measuring changes to the earth's environment. This technology allows for large regions anywhere on the globe to be observed on a frequent basis. This study demonstrates the prototype of a near-real-time early warning system using Integrated Data Fusion and Mining (IDFM) techniques with the aid of both multispectral (Landsat and MODIS) and hyperspectral (MERIS) satellite sensors to determine spatiotemporal distributions of TOC and microcystin. Landsat satellite imageries have high spatial resolution, but such application suffers from a long overpass interval of 16 days. On the other hand, free coarse resolution sensors with daily revisit times, such as MODIS, are incapable of providing detailed water quality information because of low spatial resolution. This issue can be resolved by using data or sensor fusion techniques, an instrumental part of IDFM, in which the high spatial resolution of Landsat and the high temporal resolution of MODIS imageries are fused and analyzed by a suite of regression models to optimally produce synthetic images with both high spatial and temporal resolutions. The same techniques are applied to the hyperspectral sensor MERIS with the aid of the MODIS ocean color bands to generate fused images with enhanced spatial, temporal, and spectral properties. The performance of the data mining models derived using fused hyperspectral and fused multispectral data are quantified using four statistical indices. The second task compared traditional two-band models against more powerful data mining models for TOC and microcystin prediction. The use of IDFM is illustrated for monitoring microcystin concentrations in Lake Erie (large lake), and it is applied for TOC monitoring in Harsha Lake (small lake). Analysis confirmed that data mining methods excelled beyond two-band models at accurately estimating TOC and microcystin concentrations in lakes, and the more detailed spectral reflectance data offered by hyperspectral sensors produced a noticeable increase in accuracy for the retrieval of water quality parameters.M.S.Env.E.
Masters
Civil, Environmental and, Construction Engineering
Engineering and Computer Science
Environmental Engineering
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Labrique, Françoise. "Le rituel de l'offrande de la Campagne à Edfou: étude de la composition." Doctoral thesis, Universite Libre de Bruxelles, 1991. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/213067.
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Bernardo, Luiz Carlos. "Sistemas de comunicação utilizando transmissão OFDM baseado em wavelets com subportadoras com modulação caótica." Universidade Presbiteriana Mackenzie, 2013. http://tede.mackenzie.br/jspui/handle/tede/1434.
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Previous issue date: 2013-06-14A chaotic signal based communication system represents a new wideband transmission model. Nonetheless, chaotic based systems have not yet shown a distinguished performance in terms of bit error rate when transmitted in narrow band channels or in the presence of impairments in comparison to the traditional communications systems. The focus of this work relies on an experiment that overcomes this issue, through the conjugation of the characteristics of traditional communications based in orthogonal carriers and those originated from chaotic signals. More clearly, the chaotic modulation is employed in sub-carriers of traditional OFDM (Orthogonal Frequency Division Multiplexing). This novel modulation scheme is implemented through the generation of chaotic sequences in a one dimensional map controlled by a parameter p which defines the central region of the map as a guard interval, the slope of the delimiting lines and the chaotic behavior of the generated sequence. This parameter also determines directly the amplitude of each symbol, making it more irregular and less predictable, avoiding the detection by eavesdroppers and increasing the security level of the link to be transmitted. Besides the change in the traditional OFDM modulator from 4QAM to chaotic one, the Fast Fourier Transform (IFFT /FFT) will be replaced by Wavelets Transform IDWT/DWT), in order to overcome some conventional OFDM s disadvantages Additionally a quadrature chaotic OFDM system was conceived, where the chaotic modulation was performed in a constellation I and Q that was submitted to the same channel conditions as the previous one. Both systems were simulated in a MATLAB® environment using the built in functions at the Communications System Toolbox and its behavior analyzed using the BER-Bit error rate versus SNR-Signal noise ratio. The obtained results were reported and scrutinized.
Sistemas de comunicações baseados em sinais caóticos representam um novo campo de estudo de transmissão em banda larga. Entretanto, sistemas baseados em sinais caóticos não apresentaram ainda um desempenho distinto em termos de taxa de erro, quando transmitidos em canais sem fios ou na presença de interferências em comparação aos sistemas tradicionais. O foco deste trabalho está na proposta de um novo esquema obtido através da conjugação das características da comunicação tradicional baseada em subportadoras ortogonais e aquelas originadas por sinais caóticos. Mais precisamente, a modulação caótica é empregada nas subportadoras de um sistema OFDM (Multiplexação por Divisão de Frequência Ortogonal) tradicional. Este novo modelo de modulação é implementado através de geração de sequências caóticas em um mapa unidimensional controlado por um parâmetro p que define uma região central do mapa como um intervalo de guarda e, por conseguinte, o comportamento caótico da sequência gerada. Este parâmetro também determina diretamente a amplitude de cada símbolo, fazendo-o mais irregular e menos previsível, evitando a detecção por pessoal não autorizado, possibilitando o aumento do nível de segurança da transmissão. Além da mudança no modulador do OFDM convencional de 4QAM para caótico, ter-se-á a substituição da Transformada Rápida de Fourier (IFFT/FFT), largamente utilizada em sistemas OFDM pela Transformada Wavelet (IDWT/DWT), de maneira a aprimorar os pontos fracos do sistema OFDM convencional. Como contribuição adicional, tem se a concepção do sinal com modulação simbólica em quadratura, ou seja, uma parte do sinal foi gerada no eixo I e a outra parte no eixo Q, criando uma modulação caótica em quadratura que é submetida aos mesmos canais da modulação caótica anterior. Os sistemas propostos foram simulados em ambiente MATLAB® utilizando-se de funções pré-existentes no modulo de ferramentas de comunicações (Communications System Toolbox) e o seu comportamento analisado em termos de gráficos que representam a relação da taxa de erro do bit (BER) versus relação sinal ruído (SNR). Os resultados obtidos foram reportados e debatidos.
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Rosengren, Kaj. "Modelling and implementation of an MPEG-2 video decoder using a GALS design path." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6911.
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As integrated circuits get smaller, faster and can fit more functionality, more problems arise with wire delays and cross-talk. Especially when using global clock signals distributed over a large chip area. This thesis will briefly discuss a solution to this problem using the Globally Asynchronous Locally Synchronous (GALS) design path.
The goal of this thesis was to test the solution by modelling and partially implementing an MPEG-2 video decoder connected as a GALS system, using synchronous design tools. This includes design of the system in Simulink, implementing selected parts in VHDL and finally testing the connected parts on an FPGA. Presented in this thesis is the design and implementation of the system as well as theory on the MPEG-2 video decoding standard and a short analysis of the result.
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Ritz, Julia. "Discourse-givenness of noun phrases : theoretical and computational models." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2014/7081/.
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This thesis gives formal definitions of discourse-givenness, coreference and reference, and reports on experiments with computational models of discourse-givenness of noun phrases for English and German.
Definitions are based on Bach's (1987) work on reference, Kibble and van Deemter's (2000) work on coreference, and Kamp and Reyle's Discourse Representation Theory (1993).
For the experiments, the following corpora with coreference annotation were used: MUC-7, OntoNotes and ARRAU for Englisch, and TueBa-D/Z for German. As for classification algorithms, they cover J48 decision trees, the rule based learner Ripper, and linear support vector machines. New features are suggested, representing the noun phrase's specificity as well as its context, which lead to a significant improvement of classification quality.Die vorliegende Arbeit gibt formale Definitionen der Konzepte Diskursgegebenheit, Koreferenz und Referenz. Zudem wird über Experimente berichtet, Nominalphrasen im Deutschen und Englischen hinsichtlich ihrer Diskursgegebenheit zu klassifizieren. Die Definitionen basieren auf Arbeiten von Bach (1987) zu Referenz, Kibble und van Deemter (2000) zu Koreferenz und der Diskursrepräsentationstheorie (Kamp und Reyle, 1993). In den Experimenten wurden die koreferenzannotierten Korpora MUC-7, OntoNotes und ARRAU (Englisch) und TüBa-D/Z (Deutsch) verwendet. Sie umfassen die Klassifikationsalgorithmen J48 (Entscheidungsbäume), Ripper (regelbasiertes Lernen) und lineare Support Vector Machines. Mehrere neue Klassifikationsmerkmale werden vorgeschlagen, die die Spezifizität der Nominalphrase messen, sowie ihren Kontext abbilden. Mit Hilfe dieser Merkmale kann eine signifikante Verbesserung der Klassifikation erreicht werden.
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Wargärde, Nicko. "Using WordNet Synonyms and Hypernyms in Automatic Topic Detection." Thesis, Linnéuniversitetet, Institutionen för datavetenskap och medieteknik (DM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-97745.
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Detecting topics by extracting keywords from written text using TF-IDF has been studied and successfully used in many applications. Adding a semantic layer to TF-IDF-based topic detection using WordNet synonyms and hypernyms has been explored in document clustering by assigning concepts that describe texts or by adding all synonyms and hypernyms that occurring words have to a list of keywords. A new method where TF-IDF scores are calculated and WordNet synset members’ TF-IDFscores are added together to all occurring synonyms and/or hypernyms is explored in this paper. Here, such an approach is evaluated by comparing extracted keywords using TF-IDF and the new proposed method, SynPlusTF-IDF, against manually assigned keywords in a database of scientific abstracts. As topic detection is widely used in many contexts and applications, improving current methods is of great value as the methods can become more accurate at extracting correct and relevant keywords from written text. An experiment was conducted comparing the two methods and their accuracy measured using precision and recall and by calculating F1-scores.The F1-scores ranged from 0.11131 to 0.14264 for different variables and the results show that SynPlusTF-IDF is not better at topic detection compared to TF-IDF and both methods performed poorly at topic detection with the chosen dataset.
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Marcionilo, Silva Bruno. "Chuvas intensas em localidades do Estado de Pernambuco." Universidade Federal de Pernambuco, 2009. https://repositorio.ufpe.br/handle/123456789/5222.
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Previous issue date: 2009Conselho Nacional de Desenvolvimento Científico e Tecnológico
Para dimensionamento da estrutura dos sistemas de microdrenagem e macrodrenagem, deve-se saber qual a quantidade de precipitação na área a ser drenada, associada a um período de retorno. As equações de chuvas intensas são essenciais no processo de drenagem urbana e rural de águas pluviais, apresentando grande importância para os projetos de hidráulica dos centros urbanos e sistemas de drenagem agrícola que necessitam definir a chuva de projeto para estimar a vazão de projeto dos mesmos. Além disso, as relações IDF contribuem para a diminuição da margem de erros, minimizando-se o risco de enchentes causado por chuvas de alta intensidade, como também são indispensáveis para elaboração e controle dos sistemas de drenagem e irrigação. Em função da pouca disponibilidade de informações no estado de Pernambuco quanto às equações de chuvas intensas, este trabalho tem como objetivo principal a determinação da relação IDF para algumas localidades do território pernambucano. Para isso, foram utilizados os dados de 12 estações pluviográficas e 11 estações pluviométricas, com séries históricas de 8 a 14 anos de observações (pluviógrafos) e séries de 10 a 34 anos de registros (pluviômetros). Além disso, foram realizadas comparações entre as equações geradas por dados pluviográficos e pluviométricos, objetivando avaliar a qualidade das curvas IDF oriundas de dados pluviométricos. O critério adotado para o estabelecimento das séries históricas foi o de séries anuais. Tais séries históricas foram obtidas através de análise de pluviogramas digitalizados, no caso das estações pluviográficas, e por meio da metodologia de desagregação de chuvas de um dia em tempos menores, para os pluviômetros. Na análise de freqüência das séries anuais foram aplicados o modelo de distribuição de Gumbel e o de Weibull, sendo que a segunda distribuição, na maioria dos casos estudados, apresentou os melhores ajustes com o teste de Kolmogorov-Smirnov ao nível de significância de 5% e com R² variando de 0,9199 a 0,9907. Para determinação dos parâmetros da equação de chuvas intensas foram usadas as metodologias de Regressão Linear e a Regressão não-linear, onde o segundo método apresentou melhor ajuste dos parâmetros em todas as equações desenvolvidas. Por fim, as equações geradas por meio de registros pluviométricos apresentaram bons ajustes em comparação com as relações IDF obtidas com dados de pluviogramas, com R² variando de 97% a 99,9%
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Rieskamp, Kristina-Marija [Verfasser], and Bernd [Akademischer Betreuer] Wegener. "Experimentelle Evaluation des Risikos der extradiscalen thermischen Schädigung während der intradiscalen elektrothermalen Therapie (IDET) / Kristina-Marija Rieskamp. Betreuer: Bernd Wegener." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1081899794/34.
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木村, 宏恒, and Hirotsune Kimura. "上からのマイクロクレジット : IDT（インドネシア貧困撲滅計画）の教訓." 名古屋大学大学院国際開発研究科, 1999. http://hdl.handle.net/2237/6666.
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Persegil, Eusebio Osvaldo [UNESP]. "Recomendação de adubação nitrogenada para o cultivar de algodoeiro FMT 701 com base na leitura de clorofila IDF." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/98707.
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A adubação nitrogenada é uma etapa muito importante dentro do sistema de produção do algodoeiro, tanto no aspecto de quantificação de doses, como na definição do momento de aplicação. O presente estudo teve o objetivo de avaliar o Medidor Portátil de Clorofila Falker Clorofilog, no que diz respeito à sua calibração com doses, teores foliares de nitrogênio e produtividade, além de estabelecer uma curva de recomendação de adubação nitrogenada para a cultura do algodoeiro. O trabalho foi realizado na Fazenda Mida, localizada no município de Chapadão do Céu, Estado de Goiás. O delineamento experimental utilizado foi em blocos ao acaso, com seis repetições. O experimento apresentou 6 tratamentos com adubação nitrogenada em cobertura (0, 45, 90, 120, 150 e 200 kg de N ha-1). Foram realizadas avaliações das características agronômicas, análises foliares e de solos em função das doses crescentes de adubação nitrogenada. Diante dos resultados apresentados foi verificado maior valor médio de clorofila na dose de 150 kg de N ha -1, obtendo a maior produtividade, numero de ramos produtivos e numero de capulhos por planta, para essa dosagem. Os teores foliares de Mg foram reduzidos com as doses de N e de K houve aumento. No solo, observou-se um incremento nos teores de Ca e Mg, na profundidade de 0-20 cm. Para a profundidade de 20 -40 cm, foi possível verificar redução nos teores de Ca, Mg, M.O e K quando comparado com a testemunha sem doses de N. Pode- se concluir que existe uma boa correlação entre doses de nitrogênio aplicadas em cobertura, com leituras ICF, teores foliares de nutrientes e produtividade de algodão e que é possível estabelecer uma curva de recomendação da adubação nitrogenada para algodoeiro, com base na leitura ICF no momento da adubação nitrogenada em cobertura
Nitrogen fertilization is a very important step in the system of cotton production in both the measurement of doses, as in the definition of the moment of application. This study aimed to evaluate the portable chlorophyll meter Clorofilog Falke, with respect to its calibration doses, levels of leaf nitrogen and productivity, and establish a curve of nitrogen fertilizer recommendation for cotton. The experimental design was randomized blocks with six repetitions. The experiment had six treatments with nitrogen coverage (0, 45, 90, 120, 150 and 200 kg N ha-1). Assessments were made of soil, agronomic and leaf analysis as a function of increasing levels of nitrogen fertilization. Considering the results presented chlorophyll was found in highest average 150 kg N ha-1, resulting in increased productivity, number of branches and number of bolls per plant, so that the dosage. The foliar concentrations of Mg were reduced at doses of N and K increased. On the ground, there was an increase in Ca and Mg in cm. Para depth of 0-20 cm depth of 20 -40 cm, there was a reduction in Ca, Mg, K, MO doses compared to untreated N. It can be concluded that there is a good correlation between the levels of nitrogen applied in coverage, ICF to readings, leaf nutrient concentrations and productivity of cotton and it is possible to establish a curve of the nitrogen recommendation for cotton, based on the reading ICF in time of nitrogen fertilization
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Persegil, Eusebio Osvaldo. "Recomendação de adubação nitrogenada para o cultivar de algodoeiro FMT 701 com base na leitura de clorofila IDF /." Ilha Solteira: [s.n.], 2012. http://hdl.handle.net/11449/98707.
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Orientador: Enes Furlani JúniorBanca: Samuel Ferrari
Banca: Marcio Lustosa Santos
Resumo: A adubação nitrogenada é uma etapa muito importante dentro do sistema de produção do algodoeiro, tanto no aspecto de quantificação de doses, como na definição do momento de aplicação. O presente estudo teve o objetivo de avaliar o Medidor Portátil de Clorofila Falker Clorofilog, no que diz respeito à sua calibração com doses, teores foliares de nitrogênio e produtividade, além de estabelecer uma curva de recomendação de adubação nitrogenada para a cultura do algodoeiro. O trabalho foi realizado na Fazenda Mida, localizada no município de Chapadão do Céu, Estado de Goiás. O delineamento experimental utilizado foi em blocos ao acaso, com seis repetições. O experimento apresentou 6 tratamentos com adubação nitrogenada em cobertura (0, 45, 90, 120, 150 e 200 kg de N ha-1). Foram realizadas avaliações das características agronômicas, análises foliares e de solos em função das doses crescentes de adubação nitrogenada. Diante dos resultados apresentados foi verificado maior valor médio de clorofila na dose de 150 kg de N ha -1, obtendo a maior produtividade, numero de ramos produtivos e numero de capulhos por planta, para essa dosagem. Os teores foliares de Mg foram reduzidos com as doses de N e de K houve aumento. No solo, observou-se um incremento nos teores de Ca e Mg, na profundidade de 0-20 cm. Para a profundidade de 20 -40 cm, foi possível verificar redução nos teores de Ca, Mg, M.O e K quando comparado com a testemunha sem doses de N. Pode- se concluir que existe uma boa correlação entre doses de nitrogênio aplicadas em cobertura, com leituras ICF, teores foliares de nutrientes e produtividade de algodão e que é possível estabelecer uma curva de recomendação da adubação nitrogenada para algodoeiro, com base na leitura ICF no momento da adubação nitrogenada em cobertura
Abstract: Nitrogen fertilization is a very important step in the system of cotton production in both the measurement of doses, as in the definition of the moment of application. This study aimed to evaluate the portable chlorophyll meter Clorofilog Falke, with respect to its calibration doses, levels of leaf nitrogen and productivity, and establish a curve of nitrogen fertilizer recommendation for cotton. The experimental design was randomized blocks with six repetitions. The experiment had six treatments with nitrogen coverage (0, 45, 90, 120, 150 and 200 kg N ha-1). Assessments were made of soil, agronomic and leaf analysis as a function of increasing levels of nitrogen fertilization. Considering the results presented chlorophyll was found in highest average 150 kg N ha-1, resulting in increased productivity, number of branches and number of bolls per plant, so that the dosage. The foliar concentrations of Mg were reduced at doses of N and K increased. On the ground, there was an increase in Ca and Mg in cm. Para depth of 0-20 cm depth of 20 -40 cm, there was a reduction in Ca, Mg, K, MO doses compared to untreated N. It can be concluded that there is a good correlation between the levels of nitrogen applied in coverage, ICF to readings, leaf nutrient concentrations and productivity of cotton and it is possible to establish a curve of the nitrogen recommendation for cotton, based on the reading ICF in time of nitrogen fertilization
Mestre
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Weschenfelder, Adriana Burin. "Tendências de precipitação pluvial diária e projeção de cenários aplicados à nova curva IDF para Porto Alegre-RS." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/170253.
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Neste estudo foram analisadas possíveis tendências de aumento da precipitação em nove estações pluviométricas na sub-bacia 87, incluindo Porto Alegre, no Estado do Rio Grande do Sul, para 50 anos de dados. Eventos extremos são responsáveis por muitos problemas, principalmente em áreas urbanas, e a frequência e a magnitude destes eventos podem aumentar com as alterações climáticas. No intuito de avaliar o impacto de alterações climáticas, em Porto Alegre, utilizou-se o modelo Long Ashton Research Station - Weather Generator (LARS-WG). O LARS-WG é um gerador estocástico capaz de simular cenários climáticos em escala local. Para cada série histórica das estações analisadas, na sub-bacia 87, foi aplicado o teste estatístico de Mann Kendall para identificar possíveis tendências nos dados anuais e trimestrais. Na estação de Porto Alegre também foi realizada pesquisa para identificar o aumento na frequência de ocorrência de alturas de precipitação em diferentes faixas e análise de tendência noshttp://www.bibliotecadigital.ufrgs.br/da.php?nrb=001053508&loc=2017&l=5219eb420c00bf62 dados sub-diários. A geração de séries sintéticas de precipitação para diferentes cenários teve como base os dados pluviométricos da série de Porto Alegre, que consistiu na utilização do período de 1974 a 2014 na geração da linha de base para calibração do LARS-WG. Após a geração de séries sintéticas de precipitação para um clima atual, foi selecionado o máximo diário anual e este foi desagregado em dados subdiários. Na sequência avaliou-se o impacto das alterações em três cenários do IPCC, A1B, A2 e B1. Em cada um dos arquivos de precipitação diária, geradas por projeção no LARS-WG, foi realizada a desagregação em precipitações sub-diárias Os resultados da aplicação do teste de Mann Kendall indicam tendência no aumento do total anual e no número de dias chuvosos (NDC). O trimestre que mais contribuiu para este aumento corresponde à primavera. Entretanto nas estações de Porto Alegre e Sapucaia do Sul, na região metropolitana de Porto Alegre, São Lourenço no Litoral Sul e Renânia e Serra do Pinto numa região de relevo acidentado próximo ao Litoral Norte também se identificou tendência de aumento no verão e no outono. Em Porto Alegre não foi verificada tendência na precipitação diária máxima anual, permitindo a utilização do LARS-WG que assume que as séries de dados diários observados são estacionárias e gera séries sintéticas com características estatísticas semelhantes à série de dados observados. Uma análise comparativa dos resultados entre as IDFs projetadas com o LARS-WG e a IDF definida por Weschenfelder et al. (2015) indica aumento das precipitações intensas. No primeiro período de projeção no cenário A1B, os desvios ficaram na faixa de 8 a 16% para quatro dos modelos, no cenário A2 os desvios ficaram na faixa de 9 a 19% e no cenário B1 de 7 a 19% em cinco modelos. Para o segundo período de projeção apresentou uma grande variabilidade com desvios entre -3 e 40%. O caminho para reduzir as incertezas é o monitoramento continuado das variáveis meteorológicas, pois a modelagem do clima só pode ser aprimorada com a incorporação de dados reais aos modelos.This study analyzes possible trends of precipitation increase in nine rainfall stations in subbasin 87, including Porto Alegre, in the State of Rio Grande do Sul, for 50 years of data. Extreme events are responsible for many problems, especially in urban areas, and the frequency and magnitude of these events may increase with climate change. In order to evaluate the impact of climate change in Porto Alegre, the Long Ashton Research Station - Weather Generator (LARS-WG) model was used. The LARS-WG is a stochastic generator capable of simulating local scale climate scenarios. The Mann Kendall's statistical test was applied for each historical series of the analyzed stations in sub-basin 87 in order to identify possible trends in annual and trimestral data. At the Porto Alegre station, research was also conducted to identify the increase in the frequency of occurrence of precipitation heights in different bands and trend analysis in the sub-diary data. The generation of synthetic precipitation series for different scenarios was based on the pluviometric data of the Porto Alegre series, which consisted of the use of the period from 1974 to 2014 in the generation of the baseline for LARS-WG calibration After the generation of synthetic series of precipitation for a current climate, the maximum annual daily was selected and this was disaggregated in sub-diary data. The impact of the changes was then evaluated in three scenarios of the IPCC, A1B, A2 and B1. In each of the daily precipitation files generated by LARS-WG projection, disaggregation in sub-daily precipitation was conducted. The results of the Mann Kendall test indicate a trend in the annual total increase and in the number of rainy days (NDC). The trimester that contributed most to this increase is spring. However, in the Porto Alegre and Sapucaia do Sul stations, in the metropolitan area of Porto Alegre, São Lourenço in the South Coast and Renânia and Serra do Pinto, in an area of rugged relief near the North Coast, there was also a tendency to increase in summer and fall. In Porto Alegre, no trend was observed in the annual maximum daily precipitation, allowing the use of LARSWG, which assumes that the observed daily data series are stationary and generates synthetic series with similar statistical characteristics to the data series observed. A comparative analysis of the results between the IDFs projected with the LARS-WG and the IDF defined by Weschenfelder et al. (2015) indicates an increase in intense precipitation.
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WESCHENFELDER, Adriana Burin. "Tendências de precipitação pluvial diária e projeção de cenários aplicados à nova curva IDF para Porto Alegre-RS." reponame:Repositório Institucional da CPRM, 2017. http://rigeo.cprm.gov.br/jspui/handle/doc/19015.
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Li, Chiwei, and 李奇威. "A Crest Factor Reducing Method for the OFDM System Generating by IDFT." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/55022538675148337758.
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碩士大葉大學
電機工程學系
99
A Crest Factor ( CF ) reduction method is proposed for the OFDM system that is generated by Inverse Discrete Fourier Transform ( IDFT ). By reducing the number of bits transmitted by an OFDM symbol, the crest factor can be reduced as the number of bits transmitted by a OFDM symbol decreases. The simulation results can confirm the reducing number of bits transmitled by an OFDM symbol. However, the calculation criterion is based on a CCDF of . From 4 bits to 3 bits and 2 bits, a reduction of 2.2 dB and 3.4 dB in crest factor can be obtained, respectivcly. As a result, we found that the proposed method is able to reduce the CF effectively.
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Chuan-AnChang and 張銓安. "Implementation of the Fast Fixed-Coefficient Variable Prime Length Recursive DFT, IDFT Algorithms." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/13266644909773733829.
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Wen-HoJuang and 莊文河. "A Green Implementation of the Fast Recursive DFT, IDFT, MDCT and IMDCT Algorithms." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/12312856754381246895.
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碩士國立成功大學
電機工程學系碩博士班
98
This thesis presents a green design of fast recursive discrete Fourier transform (RDFT) architecture. The advantages of the proposed design include high-throughput, power-efficient, memory-free and more reconfigurable. This thesis also discuss the issue of applying this RDFT design to Modified Discrete Cosine Transform (MDCT) and Inverse Modified Discrete Cosine Transform (IMDCT), which results in an improvement of hardware-sharing and achieves lower-cost. To improve the lack-of-efficiency problem in traditional RDFT architecture, the 2-D architecture algorithm is used in our design. Compared with the latest RDFT architecture proposed by Lai et al, 49.53% reduction of the overall clock cycles is presented in our design; and the computational amount of multiplication and addition presented are reduced to 53.60% and 53.03% of Lai’s design. In addition, the proposed architecture holds four times of DTPT (Data Throughput per Transformation, DTPT) than the traditional architecture; which achieves our goal of presenting a low complexity and low power-cost design. Furthermore, this architecture is applied on Digital Radio Mondiale (DRM) system in our design. Not only DFT computation(288、256、176、112 point) but MPGE-4 HE-AAC techniques are applied on DRM audio coding(1920、240 point). Therefore, to design a common architecture of DFT and IMDCT becomes an important issue for portable DRM receiver. This system is used to examine the performance of the RDFT architecture which we proposed in the front text as well as to discuss other architectures in this article. Moreover, this RDFT processor is implemented by using TSMC 0.18?m 1P6M CMOS technology. The core size is 0.84x0.84mm2 and the power consummation is 14.6mW@25MHz. To conclude, the proposed design would be more efficient and more suitable for DRM applications than previous works.
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Liu, Yu-Ming, and 劉郁旻. "Using WHT/IDFT as the Pre-Transform in OFDM System to Reduce PAPR by Partial Transmit Sequence." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/23957046134014145034.
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碩士國立中興大學
電機工程學系所
96
Orthogonal Frequency Division Multiplexing (OFDM) System is a special case of the multicarrier transmission system. One of the faults is the high peak-to-average power ratio( PAPR) in OFDM system. When subcarriesrs'' phase has certain combination, all of the symbol power summarize together.It causes the high PAPR. There are many ways to reduce PAPR. We select Partial Transmit Sequence (PTS) system as the main system and take the concept of the pre-transform in the PTS system to re duce PAPR. We use the Walsh-Hadamard Transform (WHT) and Inverse Discrete Fourier Transform (IDFT) as the pre-transform. According to the pre-transform’s location ,we can get the two systems for every pre-transform. High computation complexity is always the big fault of the PTS system. We will take a concept of reduction complexity algorithm for this fault and use this concept to simulate and analyze for different pre-transform systems. Besides, in order to let the weighting factor of the PTS system has error correcting ability, we encodes it and analyze for different pre-transform systems. Finally, we have the different conclusions from every simulation results and prove that using pre-transform can improve PAPR reduction performance.
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Chien, Chih-Ta, and 簡志達. "Design and Implementation of the High-performance Adder-based IP Core for the 1-D DFT/IDFT with Variable Lengths." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/09878445894553887482.
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碩士國立中正大學
資訊工程研究所
91
This Thesis proposes an efficient hardware design for the one-dimensional (1-D) discrete Fourier transform (DFT) and its inverse with variable lengths. By combining radix-2/4/8 algorithm, cyclic convolution formulation, sub-expression sharing and Cooly-Tuckey decomposition algorithm together, we have developed a parameterized hardware design for the DFT/IDFT of variable lengths ranging from 64 to 4096 points. Furthermore, we have also implemented a parameterized DSP Intellectual Property (IP) core with proposed design for meeting the system requirements of different system-on-chip (SOC) applications.
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Pereira, João da Silva. "Sequências perfeitas para sistemas de comunicação com acesso múltiplo por divisão de código." Doctoral thesis, 2012. http://hdl.handle.net/10400.8/754.
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Dissertação submetida à Faculdade de Ciências e Tecnologia da Universidade de Coimbra para a obtenção do grau de Doutor.Uma sequência perfeita é identificada quando a sua função de autocorrelação periódica é igual a um impulso unitário de Dirac ou quando todos os valores desfasados de autocorrelação são iguais a zero. No design de sequências perfeitas, a dificuldade é conseguir sequências em quantidade suficiente com baixos valores de correlação cruzada. Nesta tese, são propostos novos métodos de construção de grandes conjuntos de sequências perfeitas derivadas de uma transformada discreta e inversa de Fourier (IDFT). Cada novo conjunto de sequências de autocorrelação periódica perfeita tem um valor máximo absoluto de correlação cruzada periódica (MaxCC) estritamente inferior ao pico máximo da autocorrelação (igual ao comprimento N das sequências).Todos os valores MaxCC encontrados são iguais ou muito próximos do limite inferior teórico “raiz quadrada de N”. Não obstante, alguns dos novos conjuntos de sequências perfeitas são ortogonais e também possuem valores MaxCC baixos. Além disso, novos métodos foram sugeridos e permitiram criar ótimos conjuntos de novos códigos bipolares derivados de sequências perfeitas ortogonais e bidimensionais. É do conhecimento geral o quanto é difícil encontrar valores determinísticos tal como o MaxCC para sequências perfeitas ou mesmo para outras famílias de códigos. Este documento fornece um conjunto de novas propriedades sobre sequências perfeitas e demonstrações matemáticas que permitem determinar alguns MaxCC. Adicionalmente, foram encontrados novos limites superiores de probabilidade de erro em função do valor máximo absoluto de correlação cruzada aperiódica. Da mesma forma, a probabilidade de erro foi reescrita com base no rácio de potência de contraste da família de códigos selecionada para um determinado sistema de comunicação CDMA (Code Division Multiple Access) ou OCDMA (Optical Code Division Multiple Access). Diferentes sistemas de comunicação CDMA foram simulados com as novas famílias de sequências perfeitas. Todas as simulações mostraram como as novas sequências perfeitas e sequências quase perfeitas devem ser úteis em sistemas de comunicação. Esta tese apresenta simulações para mostrar o quanto as novas sequências perfeitas podem ser utilizadas em cenários multiusuários num sistema de comunicação CDMA por Rádio Frequência e também num sistema de comunicação OCDMA. Para um sistema OCDMA, os codificadores/descodificadores selecionados foram as SSFBG (Super Structured Fiber Bragg Grating). Este documento mostra que a seleção correta dos conjuntos de códigos escritos nas SSFBG é fundamental e os sinais óticos das SSFBG são muito parecidos com as sequências perfeitas. Todas as novas famílias de sequências perfeitas, sequências perfeitas e ortogonais, e sequências mutuamente ortogonais podem ser aplicadas em sistemas de comunicação OFDM-CDMA (Orthogonal Frequency-Division Multiplexing - Code Division Multiple Access) ou num simples sistema CDMA de comunicação. No futuro, os novos conjuntos de sequências perfeitas poderão ser utilizados em diversos sistemas de comunicação, na geração de sinais para radares e em tecnologias aplicadas a sonares.
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Shiu, Yi-Cheng, and 許益誠. "LOW-COST DESIGN OF IDCT FOR HDTV." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/77082446891281521292.
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碩士大同大學
電機工程研究所
90
In this thesis, we design a low cost processor core of IDCT for HDTV. In the HDTV application, IDCT processor must operate in 80MHz at least. In order to achieve this goad, our design in Adder-based DA algorithm with novel adder reduction technique, another coefficient code and summation network asynchronous. Under the simulation of VIRTEX V100CS144 from Xilinx Foundation F3.1i, the result shows that it is appropriate for the requirements when working at 100MHz.
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Tsai, Lei-Luo, and 蔡磊駱. "IMPLEMENTATION OF 2-D DCT/IDCT VLSI ARCHITECTURE." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/58937135731980105959.
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碩士大同工學院
電機工程研究所
87
This thesis discusses the design of a combined DCT/IDCT CMOS integrated circuit for general video application. We know that the discrete cosine transform is widely used in several international standards, in this thesis, we use a low-complexity, and high-performance architecture to realize a DCT/IDCT chip. Beside, we also use some technique (tree structure) to improve the chip performance. Based on TSMC SPTM 0.6μm CMOS technology and COMPASS 0.6μm cell library, our DCT chip is implemented. It integrates about 120k transistors, and die size occupies a silicon area of 5415μm x 5495μm, and simulation results show that the clock rate can be up to above 85MHz that conforms our requirement.
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Lin, Chun-Pin, and 林俊賓. "The Implementation of A Novel DCT/IDCT Chip." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/25856889946127942021.
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碩士淡江大學
電機工程學系
88
The discrete cosine transform (DCT) is widely used in digital signal processing, particularly for digital image processing. Because of the complicated computational complexity, many efficient algorithms are proposed to improve the computing speed and hardware complexity. Discrete cosine transform (DCT) is used as core technique in the CODEC systems based on the compression standards of JPEG and MPEG. DCT can be implemented to integration circuits thanks to mature of semiconductor technology. The goal of this thesis is to design and implement a two-dimensional 8x8 discrete cosine transform chip for real-time applications. For real time application, this architecture of this DCT/IDCT chip contains the following features: (1) Modified butterfly architecture are applied to reduce a part of the adders, subtracters and multipliers. And make all coefficients of the modified butterfly architecture are positive to simplify the multiplier design. (2) Booth coding scheme and Wallace tree architecture are used to reduce the numbers of non-zero bit of coefficients and implementation the fast multiplier. (3) Pipelining architecture are applied to the parallel processing in order to reduce the total computing time efficiently.(4) Two transpose memory blocks are used to reduce the waiting state and to improve the latency. For 8x8 an information block, the latency only needs 37 clock cycles. The design is used Verilog HDL to implement the circuit modules and synthesis the modules with the cell library provided by CIC and synthesis tools provided by Synopsys. Then the Cadence CAD is used to do the auto-place-and-route (APR) and verification. Finally, transistor level simulation is analyzed with Timemill provided by EPIC.
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Wu, Yo-Lin, and 吳侑霖. "Reversible data hiding using Histogram shifting on IDWT." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/44p452.
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碩士國立彰化師範大學
資訊工程學系
105
As the internet keeping developing, copyright protection of the digital contents has become more and more important. As a good solution to prevent malicious steals and attacks, digital watermarking has become very popular in recent years. Digital watermarking can be applied to data hiding. In some case, we need to recover the cover image after extracting the data from the image which is watermarked. Reversible watermarking has been developed for recovering the cover image after extracting the watermark from the cover image. In this paper, we investigated about the improvement of images using reversible watermarking. In previous work, reversible watermarking can embed less amount of watermark, so we proposed an improved reversible watermarking method. The grayscale cover images are transformed by integer discrete wavelet transform (IDWT) and the resulting frequency coefficients are selected for watermark embedding.
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Liu, Min-Chih, and 劉旻智. "VLSI IMPLEMENTATION OF 2-D DCT/IDCT ARCHITECTURE." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/58319845538696646120.
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碩士大同大學
電機工程學系(所)
96
The digit compress technology is concerned by people extremely. The 2-D DCT and IDCT are widely used and the most effective compression technology in image compressing. There are also a lot of new algorithms being proposed all the time, but most structure application will spend too much cost. This paper takes the short time to market and low cost as the direction in design. We make the design to be an DCT/IDCT IP under the consideration of the area and speed of the chip. Though 2-D DCT/IDCT roughly are divided into row-column decomposition (RCD) and not row-column decomposition (NRCD). NRCD is more efficient than RCD, but it is relatively too complex for hardware to be implemented. So the design structure of this thesis also uses RCD as usual. And in order to get higher throughput, it uses two 1-D DCT/IDCT circuit units to do parallel operation. It also uses the improved shift-and-add multiplication logic to balance each multiplication path and save hardware resource. Combined with the concept of pipeline, the design can deal with input data continually. Finally, we can ensure the design reaching the requirements with the function and timing checking. Then we enforce placement and routing steps of back-end flow to finish the physical layout and make physical verifications to guarantee that the chip can be tape-outed.
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Chen, Ting-Yu, and 陳亭諭. "Efficient BIST Techniques for Two-Dimensional DCT / IDCT Processor." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/97537645511103647119.
Full textAbstract:
碩士輔仁大學
電子工程學系
91
In this paper, we propose a fully parallel systolic array architecture by using row-column decomposition method for 2D-DCT/IDCT applications. The architecture proposed possesses many advantages such as (1) the regularity of this architecture is higher than others. (2) control signals are greatly simplified. (3) it meets all MPEG-2 specifications. It is a high throughput architecture which performs one complete N × N—point transform per N clock cycles, and the latency of the architecture is only 2 N clock cycles. ,and (4) the architecture is very flexible. We use QuartusII software of Altera Corp. to simulate the circuit function and compare the results with the simulation results of the software implementation. The simulation results show that the architecture proposed can work correctly. For chip testing consideration, we modify the processing elements of array and make it bijective. We choose the cell fault model for multiplier and adder units. Then we combine the adder with the register file to perform accumulation and compression functions to evaluate the signatures of different test sessions. The signatures of each testing session are stored in each processing element and propagated to the primary outputs when the test session is done. We also propose a very efficiently BIST method. The TPGs can be implemented with several simple binary counters. Finally, the order of each BIST session is decided by the corresponding silicon area covered by that test session. This will efficiently shorten the test time.
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CHIEH, TASI JEN, and 蔡仁傑. "Scalable DCT/IDCT Processor Design Using Prime-Factor Algorithm." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/99061536319178199211.
Full textAbstract:
碩士國立交通大學
電機與控制工程系
89
DCT ( Discrete Cosine Transform ) has been widely used in digital signal processing , especially in image and audio processing. Although a large number of papers have been proposed to meet the real-time requirements, most of them can only deal with either 1-D or 2-D DCT/IDCT and the fixed-length DCT/IDCT. In order to increase the flexibility, this thesis proposes a scalable, parameterized DCT/IDCT processor using Prime-Factor Algorithm (PFA). The proposed architecture can perform both 1-D and 2-D variable length DCT/IDCT and features high degree of regularity and modularity. Finally, a prototype chip has been built using TSMC 0.35mm CMOS technology. The chip is packaged by 100 LD CQFP and can be operated at 45.5 MHz.
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林郁翔. "Hardware architectures for the H.265-HEVC DCT/IDCT." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/4skwbh.
Full textAbstract:
碩士國立彰化師範大學
資訊工程學系
105
It is that digital multimedia change the communication and life of human. It has the huge influence on human civilization. Data compression and video encoding are the important technology in the digital multimedia. Because H.264-AVC (Advanced Video Coding) has high efficiency data compression and video encoding, It has the huge influence in many kinds of Multimedia services. The International Telecommunication Union (ITU) has officially agreed on the release of the new video coding standard ITU-T H.265 (HEVC) January 25, 2013. H.265-HEVC is based on H.264-AVC, but it provides more flexible, more reliable and more stable than H.264-AVC. in the same quality, H.265-HEVC uses half of data volume than H.264-AVC, but H.265-HEVC provides methods and algorithm are more complex than H.264-AVC. This paper introduce the discrete cosine transform (DCT) and inverse discrete cosine transform (IDCT) which applied to H.265-HEVC. Hardware and Software of DCT in this paper is implemented based on the DCT algorithm which is proposed by Grzegorz- Pastuszak and hardware and software of IDCT is implemented based on the modifying Row/Column DCT. Compared the results of data to the traditional software of two-dimensional DCT / IDCT and hardware of two-dimensional DCT / IDCT, performance of PSNR in hardware are not much difference from software, but the processing speed obtain improved dramatically
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Tseng, Chung-Ching, and 曾仲卿. "Reduced Coefficient 2-D IDCT Architecture Design for MPEG Decoder." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/68788258094806577025.
Full textAbstract:
碩士國立交通大學
電子研究所
83
In recent years, video compression techniques are widely applied and the 2-D DCT is recognized as the most effective technique. In MPEG, the DCT is postprocessed with quantization and most of the DCT coefficients are quantized to be zero. By using this characteristic; we developed a reduced coefficient 2-D IDCT algorithm. It is not only efficient for decoding but also its architecture is well suited for VLSI implementation. In this thesis, we proposed this two-dimensional inverse discrete cosine transform (2-D IDCT) algorithm based on base matrices and its symmetrical property, and then use the property of cosine product by sum-difference to reduce the number of multiplications. Thus the average number of multiplications with this algorithm is one-tenth comparing to the conventional row-column method. The average number of additions is also less than conventional row-column method. The IDCT chip totally uses 12500 gates; and thus is area efficient. The operation speed of IDCT chip is 80 MHz, and thus it computes one less than 2.5 us per 8x8 block that can satisfy the requirement of MPEG-2.
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曾盟鈞. "A Design of High Performance 2-D DCT/IDCT Processor." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/35714584534535445296.
Full textAbstract:
碩士中華大學
電機工程研究所
86
Discrete Cosine Transform (DCT) has been commonly adopted in many transformation application such as image, video, and facsimile. The discrete transform (DCT) has been recognized as one of the standard techniques in image compression. Therefore, a core processor that rapidly compputes DCT/IDCT has become a key comonent-in image compression in VLSI implementation. This paper describes ka 100-MHz two-dimensional DCT/IDCT core processor, whice is applicable to the real-time processigng of H.263 signals. Furthermore, mean values of errors generated in the core were minimezed to enhance the computational accuracy with the word-length constraints. Consequently,it features the fast operating speed under the low area with ist sufficient accuracy satisfying the specifications in CCITT recommendation H.263.
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Chen, Yih-Chien, and 陳逸謙. "Characteristics of SAW Filter with Split IDT." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/55074278522623587248.
Full textAbstract:
碩士國立成功大學
電機工程研究所
84
Surface Acoustic Wave Filters (SAWF) are basically manufactured by depositing two Interdigital Transducers (IDT)on the polished surface of the piezoelectric substrate the input IDT can transfer the input electrical signal into Rayleigh Wave,the waves propagate on the surface of the substrate, and then are recived and transfered into electrical signals again by the output IDT. The filter effect is made through the transfering process. In this thesis, the principles, the manufacture processes and the equivalent circuit of the SAWF are introduced first. Then five different SAW filters with the same center frequency (about 28MHz) but different design parameters are successfully produced on Y-128°LiNbO3 substrate. After the devices are produced, their basic properties, such as frequency response, phase, conductance, susceptance are test to understand the effect of design parameters on the characteristics of SAW filters. At last, the results of expermental are compare with that of simulation.
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李俊凌. "A Fast and Scalable DCT/IDCT Processor Based on CORDIC Algorithm." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/14801633000485549844.
Full textAbstract:
碩士國立臺灣科技大學
電機工程技術研究所
86
Progress in various fields of digital technology have made possible many applications of digital video such as hgh-definition television (HDTV),teleconferencing, and multimedia communications, These applications require high-speed transmission of vast amounts of video dato. Most video standards such as HDTV video conding, H. 261, JPEG, and MPEG use discrete cosine transform (DCT) as a standard transform coding scheme. The DCT is, however, very computationally intensive. To realize high-speed and cost-effective DCT for video coding, one needs efficient VLSI implementations so that the real time requirements can be matched. In our thesis, we propose a scalable and parallel architecture for DCT/IDCT.In the architecture, we employed an alternative arithmetic computing algorithm known as CORDIC (COordinate Rotation Digital Computer) to efficiently evaluate each of elementary functions in DCT/IDCT.By the properties of DCT/IDCT algorithm we adopt, we improve the hardware implementation and diminish the control circuit for computing cosine function.
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Chang, Chih-Chun, and 張智淳. "A Parameterized On-Chip-Bus-Compliant FDWT/IDWT Accelerator IP Generator." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/91601040045984449416.
Full textAbstract:
碩士國立清華大學
資訊工程學系
92
We propose a generator for hardware acceleration of Discrete Wavelet Transform (DWT) with various coefficient parameters. Not only (5, 3) and (9, 7) DWT filters defined in the JPEG2000 image compression standard but also other filters, such as (9, 3), (6, 10) and (2, 2), can also be generated. The generated DWT IP can perform both forward and inverse transform (FDWT and IDWT). Our generator also provide on-chip-bus interface compliant with AMBA protocol and associated device driver so that the generated IPs are ready for SOC integration. We verify the proposed approach by integrating generated IPs into an SOC platform running JPEG2000 application software. Experimental results demonstrated that the proposed approach is indeed effective in enhancing the productivity of hardware accelerator IP design.
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Chih-Sheng, Huang, and 黃志聖. "The Design and Implementation of DCT/IDCT Chip with Novel Architecture." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/27326219756381096351.
Full textAbstract:
碩士淡江大學
電機工程學系
87
Along with the progress of computer technology, the application of digital techniques such as HDTV and Videoconference include a large amount of pictures and image information. In order to store and transmit these data, it is an exigent issue how to compress them efficiently. JPEG and MPEG are the compression standards made for solving these problems. Discrete cosine transform (DCT) is used as core technique in the CODEC systems based on the compression standards of JPEG and MPEG because DCT is a very efficient technique among all approaches of image compression. DCT can be implemented to integration circuits thanks to mature of semiconductor technology. In the thesis, new architecture for VLSI implementation of real time DCT/IDCT chip is designed. For real time application, This architecture contains the following features: (1) Use modified butterfly architecture to reduce a part of the adders, substrators, and multipliers. And make all coefficients of the modified butterfly architecture are positive to simplify the multiplier design. (2) Use Booth coding scheme to reduce the numbers of non-zero bit of coefficients, and using Wallace tree architecture to implementation faster multipliers. (3) Use pipeline architecture for the parallel processing in order to reduce the total computing time efficiently. We use Verilog HDL to implement the circuit modules and synthesis the modules with the cell library provided by CIC and synthesis tools provided by Synopsys. Then the Cadence CAD is used to do the auto-place-and-route (APR) and verification. Finally, transistor level simulation is analyzed with TimeMill provided by EPIC.
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朱瑞欽. "An efficient adder-based 2-D DCT/IDCT IP core design." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/58577354836897901875.
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Hung, Ming-Chi, and 洪明吉. "VLSI Implementation of An Area Efficient 2-D DCT/IDCT Architecture." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/36736917762404073846.
Full textAbstract:
碩士逢甲大學
自動控制工程學系
89
There are many efficient VLSI architectures of 2-D DCT and 2-D IDCT for area and processing speed points of view. However, most of them spend much cost for using in a real-time digital video codec system. The aim of our research work was to develop an area efficient and low complexity VLSI architecture of 2-D DCT and 2-D IDCT for real-time digital low bit-rate video codec system. Hardware cost and performance of this architecture are main key point. It is based on the row-column decomposition technique. This architecture would be shown that a single 1-D DCT/IDCT could take role of 2-D DCT and 2-D IDCT. It can be achieved through precise timing scheduled. Intuitively, three 1-D DCT/IDCT and a matrix transposition could be saved as compared to the conventional architectures which usually use two one-dimensional transforms and transposition memory. To reduce its processing time, the proposed architecture used 3-bit serial distributed arithmetic, parallel and pipelined method. We simulated the finite wordlength of the proposed 2-D DCT/IDCT algorithm with C language. Then, based on TSMC 0.35um process technique, Galax! 0.35um cell library is used to implement the 2-D DCT/IDCT architecture. In proposed architecture, 11895 gates were consumed roughly for 45 MHz operating clock. As a result, this architecture can be characterized to maximize the utilization of the hardware resources. It also can be applied to the ASIC chips for real-time digital low bit-rate video codec system and multimedia services especially requiring low cost and low hardware complexity.