Dissertations / Theses on the topic 'Fixed-matrix'
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Peacock, Matthew James McKenzie. "Random Matrix Theory Analysis of Fixed and Adaptive Linear Receivers." University of Sydney, 2006. http://hdl.handle.net/2123/985.
Full textThis thesis considers transmission techniques for current and future wireless and mobile communications systems. Many of the results are quite general, however there is a particular focus on code-division multiple-access (CDMA) and multi-input multi-output (MIMO) systems. The thesis provides analytical techniques and results for finding key performance metrics such as signal-to-interference and noise power ratios (SINR) and capacity. This thesis considers a large-system analysis of a general linear matrix-vector communications channel, in order to determine the asymptotic performance of linear fixed and adaptive receivers. Unlike many previous large-system analyses, these results cannot be derived directly from results in the literature. This thesis considers a first-principles analytical approach. The technique unifies the analysis of both the minimum-mean-squared-error (MMSE) receiver and the adaptive least-squares (ALS) receiver, and also uses a common approach for both random i.i.d. and random orthogonal precoding. The approach is also used to derive the distribution of sums and products of free random matrices. Expressions for the asymptotic SINR of the MMSE receiver are derived, along with the transient and steady-state SINR of the ALS receiver, trained using either i.i.d. data sequences or orthogonal training sequences. The results are in terms of key system parameters, and allow for arbitrary distributions of the power of each of the data streams and the eigenvalues of the channel correlation matrix. In the case of the ALS receiver, we allow a diagonal loading constant and an arbitrary data windowing function. For i.i.d. training sequences and no diagonal loading, we give a fundamental relationship between the transient/steady-state SINR of the ALS and the MMSE receivers. We demonstrate that for a particular ratio of receive to transmit dimensions and window shape, all channels which have the same MMSE SINR have an identical transient ALS SINR response. We demonstrate several applications of the results, including an optimization of information throughput with respect to training sequence length in coded block transmission.
Ko, Lok Shun. "Matrix fixed charge density modulates exudate concentration during cartilage compression." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=117081.
Full textLe potentiel d'écoulement est due à la présence de charges fixes négatives sur les glycosaminoglycanes de la matrice extracellulaire du cartilage. Son évaluation arthroscopique peut potentiellement détecter les lésions localisées et fournir de l'information diagnostique quantitatif. La filtration d'électrolyte est également un phénomène découlant des glycosaminoglycanes. Généralement supposé négligeable malgré un manque de validation expérimentale, il peut être important pour la conception et l'interprétation des measurements du potentiel d'écoulement et pour le choix des suppositions de modélisation. L'objectif de cette thèse est donc de quantifier le phénomène de filtration d'électrolyte et d'estimer son effet sur les mesures de potentiel d'écoulement. La concentration de chlorure dans l'exsudat de cartilage comprimé a été mesurée et le contenu de GAG a été colorimétriquement dosé. Des études pilotes ont indiqué qu'une vitesse de déformation de 8x10^(-3) s^(-1) était appropriée afin d'éliminer les préoccupations d'évaporation d'exsudat ainsi que du dommage à l'explant (à haute et basse vitesses, respectivement). La concentration d'exsudat des explants équilibrés dans 1x PBS et soumis à une deformation de 37,5, 50 et 62,5% était significativement (p<0.05) inférieure à celle du bain, avec claire dépendance sur la magnitude de déformation. Elle était également significativement inférieure lorsqu'une deformation de 50% a été appliquée après l'équilibrage en 0,5, 1 et 2x PBS. La différence relative avec le bain semblait augmenter avec la diminution de la concentration de celui-ci (p=0,065 entre 0,5 et 2 PBS). La baisse de concentration de l'exsudat a corrélé négativement avec le contenu de glycosaminoglycanes post-compression, alors qu'aucune différence n'a jamais été détectée dans l'exsudat des explants d'agarose. Nos résultats démontrent que la concentration d'exsudat de cartilage comprimé est dilué par rapport au bain en raison de la présence des charges fixes. Cette différence mène à la génération de potentiels de diffusion durant la mesure du potentiel d'écoulement, surtout sous les conditions de haute déformation et de faible vitesse de deformation.
Garcia, Ignacio de Mateo. "Iterative matrix-free computation of Hopf bifurcations as Neimark-Sacker points of fixed point iterations." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2012. http://dx.doi.org/10.18452/16478.
Full textClassical methods for the direct computation of Hopf bifurcation points and other singularities rely on the evaluation and factorization of Jacobian matrices. In view of large scale problems arising from PDE discretization systems of the form f( x (t), α ), for t bigger than 0, where x are the state variables, α are certain parameters and f is smooth with respect to x and α, a matrix-free scheme is developed based exclusively on Jacobian-vector products and other first and second derivative vectors to obtain the critical parameter α causing the loss of stability at the Hopf point. In the present work, a system of equations is defined to locate Hopf points, iteratively, extending the system equations with a scalar test function φ, based on a projection of the eigenspaces. Since the system f arises from a spatial discretization of an original set of PDEs, an error correction considering the different discretization procedures is presented. To satisfy the Hopf conditions a single parameter is adjusted independently or simultaneously with the state vector in a deflated iteration step, reaching herewith both: locating the critical parameter and accelerating the convergence rate of the system. As a practical experiment, the algorithm is presented for the Hopf point of a brain cell represented by the FitzHugh-Nagumo model. It will be shown how for a critical current, the membrane potential will present a travelling wave typical of an oscillatory behaviour.
Dhanani, S. "Application of a social accounting matrix (SAM) fixed-price multiplier model to agricultural sector analysis in Pakistan." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382509.
Full textHrbáček, Jiří. "Experimentální podpora vývoje specifického integrovaného zařízení." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442834.
Full textFerrari, Peron Costa Priscila [Verfasser]. "Evaluation of clinical indices, microbiological and matrix metalloproteinase-8 levels in subgingival biofilm of patients with fixed appliance, before and during orthodontic treatment / Priscila Ferrari Peron Costa." Mainz : Universitätsbibliothek Mainz, 2020. http://d-nb.info/1213271452/34.
Full textMateo, Garcia Ignacio de [Verfasser], Andreas [Akademischer Betreuer] Griewank, Nicolas R. [Akademischer Betreuer] Gauger, and Willy J. F. [Akademischer Betreuer] Govaerts. "Iterative matrix-free computation of Hopf bifurcations as Neimark-Sacker points of fixed point iterations / Ignacio de Mateo Garcia. Gutachter: Andreas Griewank ; Nicolas R. Gauger ; Willy J. F. Govaerts." Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2012. http://d-nb.info/1020871148/34.
Full textLydia, Emílio Jorge. "Um método de matriz resposta com esquema iterativo de inversão parcial por região para problemas unidimensionais de transporte de nêutrons monoenergéticos na formulação de ordenadas discretas." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3208.
Full textPresented here is a response matrix (RM) method, which solves numerically fixedsource one-speed slab-geometry neutron transport problems in the discrete ordinates (SN) formulation. The numerical solutions are completely free from spatial truncation errors. Therefore, the RM method with the RBI iterative scheme converges numerical values for the region-edge angular fluxes, which coincide with the numerical values generated from the analytical solution, apart from computational finite arithmetic considerations. A spatial reconstruction scheme has also been developed to yield the detailed profile of the scalar flux using a fixed step defined by the code user. Numerical results are given to illustrate the offered methods accuracy.
Sarracini, Junior Fernando. "Sintese de controladores H 'Infinito' de ordem reduzida com aplicação no controle ativo de estruturas flexiveis." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263105.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: A implementação de controladores de ordem reduzida (fixa) demanda um menor esforço de processamento e consequentemente recursos de hardware menos sofisticados em relação à implementação de controladores de ordem completa. Este trabalho mostra que a implementação prática de controladores H 00 de ordem fixa voltados para o controle de estruturas flexíveis é factível. A obtenção de tais controladores é um problema considerado difícil por ser nãoconvexo. Para contornar as dificuldades numéricas de obtenção dos controladores de ordem fixa, uma combinação do método Lagrangiano Aumentado com Desigualdades Matriciais Lineares (LMls) é utilizada. Uma estrutura de viga com engaste em uma de suas extremidades é modelada através do método de Elementos Finitos. Controladores Hoc de ordem fixa e de ordem completa são projetados com base em um modelo matemático truncado. Incertezas de modelagem e a presença de modos próximos na região de frequência de interesse dificultam a obtenção de controladores que garantam a estabilidade e um desempenho satisfatório. Para contornar estas dificuldades, usa-se a técnica de controle robusto Hoo e filtros de ponderação. Dessa forma, procura-se minimizar o efeito das incertezas e evitar que modos que não foram considerados durante a fase de projeto dos controladores não sejam excitados, garantido assim a não ocorrência do fenômeno denominado spillover. Controladores Hoo de ordem completa e ordem fixa são implementados na prática e os resultados experimentais são comparados com resultados simulados
Abstract: The implementation of reduced (fixed ) order controllers requires a smaller computational effort and. consequently, less advanced hardware resources in relation to the implementation of full order controllers. This work shows that the practical implementation of fixed order Hoo controllers directed toward the control of flexible structures is viable. Obtaining such controllers is considered a difficult task for being a non-convex problem. To overcome the numerical difficulties of attainment of fixed order controllers, a combination of the Lagrangian method increased with Linear Matrix Inequalities (LMIs) is used. A cantilever beam is modelled with the Finite Element Method. Fixed and full order controllers are designed based on a truncated mathematical model. Modelling uncertainties and the existence of near modes in the frequency range of interest make difficult the attainment of controllers that assure the stability and the performance of the system. To overcome this difficulty, the robust Hoo control and weighing filters are used. In this way, it is desired to minimize the effect of uncertainties and avoid the excitement of non-modelled modes, assuring that the spillover phenomenon does not occur. Full order and fixed order H x controllers are implemented in the practice and the experimental results are compared with the simulated results
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
Guida, Mateus Rodrigues. "Método numérico de Matriz Resposta acoplado a um esquema de reconstrução espacial analítica para cálculos unidimensionais de transporte de nêutrons na formulação de ordenadas discretas multigrupo de energia com fonte fixa." Universidade do Estado do Rio de Janeiro, 2011. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=6176.
Full textUm método de Matriz Resposta (MR) é descrito para gerar soluções numéricas livres de erros de truncamento espacial para problemas multigrupo de transporte de nêutrons com fonte fixa e em geometria unidimensional na formulação de ordenadas discretas (SN). Portanto, o método multigrupo MR com esquema iterativo de inversão nodal parcial (NBI) converge valores numéricos para os fluxos angulares nas fronteiras das regiões que coincidem com os valores da solução analítica das equações multigrupo SN, afora os erros de arredondamento da aritmética finita computacional. É também desenvolvido um esquema numérico de reconstrução espacial, que fornece a saída para os fluxos escalares de nêutrons em cada grupo de energia em um intervalo qualquer do domínio definido pelo usuário, com um passo de avanço também escolhido pelo usuário. Resultados numéricos são apresentados para ilustrar a precisão do presente método em cálculos de malha grossa.
Shah, Kumar. "Quantitative Analysis of Tobacco Specific Nitrosamine in Human Urine Using Molecularly Imprinted Polymers as a Potential Tool for Cancer Risk Assessment." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1954.
Full textGodoi, Cláudio Roberto Cardoso de. "Divergência genética e predição de valores genotípicos em soja." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/3884.
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Soybean breeding programs practice selection of high genetic value genotypes with two main objectives: a) to use them as parents in the hybridization process (first stage of the program), and b) to indicate them as new cultivars (final stage of the program). In this context, a first study used microsatellite markers (SSR) to assess the genetic diversity of soybean germplasm adapted to the Brazilian conditions. The experimental material consisted of 192 accessions, which included both introductions and Brazilian germplasm. The genetic divergence was assessed by descriptive analysis and the Rogers-W genetic distance. A total of 222 alleles were identified in the 37 genotyped loci, with an average of six alleles and a range of 2 to 14 alleles per locus. The genotypes were clustered according to the origin of the germplasm, and resulted in two groups: one group formed by introductions and other by Brazilian genotypes. Eighty five percent of the genetic distances estimates were above 0.70, suggesting that the assessed germplasm has good potential for hybridization in soybean breeding programs. It was concluded that the SSR markers are useful to identify divergent genotypic groups, as well as genotypic combinations with high genetic variability. It also became clear that the use of introduced germplasm ensures the incorporation of alleles necessary to increase the genetic base of soybeans and, consequently, the variability needed for the selective process. In a second study, the mixed model approach was used to assess some strategies of estimation and prediction of genotypic values for grain yield in the soybean regional yield trials. A total of 111 genotypes classified into three maturity groups were sown in up to 23 experiments in Central Brazil. The experiments were carried out in randomized complete block designs, with three replications. The biometrical analyses followed the fixed model and mixed model approaches, in the latter case assuming the genotypic effects as random. In the mixed model approach, analyses were made with or without information from the relationship estimates obtained either by genealogy or SSR markers, arranged in a genotypic covariance matrix (G). Also, in a context of spatial analysis, different structures were used in the residual covariance matrix (R) for each mixed model adjusted. The following conclusions were obtained: i) the fixed model analysis is adequate to estimate genotypic values in soybean trials with balanced data and orthogonal design; ii) under such conditions and intermediate to low heritability, the inclusion of relationship information associated to G matrix, although does not ensure the best fit models, improves the precision in predicting genotypic values; iii) the use of spatial structures associated to R matrix, in presence of the residual autocorrelation, improves the goodness of model fit to the data; and, iv) the choice of model for the analysis does not change the ranking of the genotypes in high heritability situations and, therefore, does not impact significantly on the selection of superior genotypes.
Os programas de melhoramento de soja visam à seleção de genótipos de alto valor genético, com a finalidade de uso principalmente em duas de suas etapas: a) como genitores no processo de hibridação (fase inicial); e, b) para indicação como nova cultivar (fase final). Nesse contexto, num primeiro estudo avaliou-se, por meio de marcadores microssatélites (SSR), a diversidade genética em germoplasma de soja adaptado às condições brasileiras. O material experimental constituiu-se de 192 acessos, entre introduções e germoplasma de origem nacional. Na avaliação da divergência genética, considerou-se a análise descritiva e a distância genética de Rogers-W. Nos 37 locos genotipados, identificaram-se 222 alelos, com média de seis alelos por loco e variação de 2 a 14 alelos. O agrupamento dos genótipos mostrou-se associado à origem do germoplasma, resultando em dois grupos: um introduzido e outro brasileiro. Das estimativas de distâncias genéticas obtidas, 85% foram superiores a 0,70, indicando bom potencial do germoplasma para hibridações em programas de melhoramento da soja. Concluiu-se que os marcadores SSR são úteis na identificação de grupos genotípicos divergentes, bem como de combinações de alta variabilidade genética. Ademais, o uso de germoplasma introduzido garante a incorporação de alelos necessários à ampliação da base genética da espécie e, consequentemente, da variabilidade necessária para uso no processo seletivo. Num segundo estudo, no contexto da análise de modelos mistos, avaliaram-se estratégias de estimação e predição de valores genotípicos para produtividade de grãos, a partir de ensaios de competição final de linhagens de soja. Os genótipos, em número de 111 e classificados em três grupos de maturação, foram semeados em até 23 experimentos conduzidos na região central do Brasil. Os experimentos foram conduzidos no delineamento de blocos completos casualizados, com três repetições. Nas análises biométricas adotaram-se as abordagens de modelo fixo e de modelo misto, neste caso, assumindo-se efeitos genotípicos como aleatórios. Na última abordagem, consideraram-se ainda análises com ou sem uso da informação de parentesco genético, obtida a partir de genealogias ou por marcadores SSR, e associada à matriz de covariâncias dos efeitos aleatórios (G). Para cada modelo, num contexto de análise espacial, adotaram-se também distintas estruturas para a matriz de covariâncias residuais (R). Concluiu-se, então, que: i) a análise com modelo fixo é adequada para estimar efeitos genotípicos em soja, sob condições de balanceamento dos dados e ortogonalidade do delineamento; ii) sob tais condições, a inclusão da informação de parentesco associada à matriz G, embora não garanta melhor ajuste aos modelos, sob herdabilidade moderada ou baixa, melhora a precisão das predições de valores genotípicos; iii) o uso de estruturas espaciais associadas à matriz R, na presença de autocorrelação residual, melhora o ajuste estatístico dos modelos; e, iv) corrobora-se a tese de que, sob alta herdabilidade, a escolha do modelo de análise não altera o posicionamento relativo dos genótipos, e, portanto, não impacta significativamente na seleção de genótipos superiores.
Schönherr, Marek. "Improving predictions for collider observables by consistently combining fixed order calculations with resummed results in perturbation theory." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-83876.
Full textKhalid, Adeel S. "Development and Implementation of Rotorcraft Preliminary Design Methodology using Multidisciplinary Design Optimization." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14013.
Full textPasca, Bogdan Mihai. "Calcul flottant haute performance sur circuits reconfigurables." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2011. http://tel.archives-ouvertes.fr/tel-00654121.
Full textVestin, Albin, and Gustav Strandberg. "Evaluation of Target Tracking Using Multiple Sensors and Non-Causal Algorithms." Thesis, Linköpings universitet, Reglerteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-160020.
Full textChen, Yen-Wen, and 陳彥文. "Fixed-Slope Carrier Modulation for Indirect Matrix Converter." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/7qu94x.
Full text國立中山大學
電機工程學系研究所
106
When it comes to AC/AC conversion, AC/AC converters that have a dc-link capacitor to be an energy buffer between two ac systems and regulate dc-link voltage are commonly used. However, this capacitor affects life and volume of the converter device and requires soft-start circuit to prevent excessive inrush current. In recent years, with the innovation and development of power electronics, indirect matrix converter was proposed; this topology is more complex in modulation, but no drawbacks that caused by a dc-link capacitance. In this thesis, a carrier-based modulation method is proposed to implement zero current commutation (ZCC) in an indirect matrix converter (IMC) with a fixed-slope carrier. This method reduces the difficulty of producing switching signals that follows ZCC by modifying reference signals of carrier-based PWM method that needs a varying-slope carrier. The modified reference signals can then be used in PWM processes with a fixed-slope carrier. Moreover, there is no jump discontinuity in the modified reference signals, which can avoid abrupt changes in control that cause switching errors. At the end, the feasibility of this method is verified by experiments as input power factor correction, output frequency limitation test and output load variation.
Hung, Chun-Yao, and 洪峻堯. "Fixed-Slope Carrier Modulation for Direct Matrix Converter." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/87ewt5.
Full text國立中山大學
電機工程學系研究所
107
In recent years, the technology of power electronics becomes more mature, the issue of AC/AC conversion has also received much attention. The conventional AC/AC converters covert energy in the form of AC to DC and then AC, the part of dc-link usually uses capacitor for voltage regulation and energy storage. However, this capacitor has short lifetime and large size in the converter, and the additional soft-start circuit is needed to prevent the occurrence of excessive inrush current. In recent years, the matrix converter was proposed, this topology is more complex in modulation design, but no drawback from dc-link capacitor. In this thesis, a fixed-slope carrier modulation method is proposed to implement three steps hybrid commutation method in the direct matrix converter. Because this method uses fixed slope carrier, so that is easier than space vector modulation and variable-slope carrier method to implement the switch signals. Moreover, the modulation signals of proposed method are more continuously, which can’t easy to cause switching errors in control. At the end, the feasibility and reliability of this method is verified by testing the steady and dynamic experiment of output frequency variation, output magnitude variation and output load variation from output side.
Chang, Guo-Cia, and 張國財. "Fixed - Order H_inf Controllers Design via Linear Matrix Inequality Approach." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/56665843130459052378.
Full text國立中正大學
化學工程研究所
92
A bilinear matrix inequality(BMI) approach for designing controller of control engineering is the point of this thesis . First of all , we dissus -stability , pole placement , time-delay problems of static ouput feedback(SOF) system. Fixed-order H_inf control problem is a general problem in robust control , this problem can be a linear matrix inequality problem by Bound Real Lemma .The fixed-order H_inf control problem is to find a controller such that the closed loop system is stable and the H_inf -norm of the closed loop transfer function is strictly less than a constant gamma . Time-delay problems are general in chemical process. We design stable fixed-order H_inf controller for constant time-delay system by a bilinear matrix inequality approach.Finally , we also dissus time-varying-delay system.
Haung, Wei-Cheng, and 黃暐程. "A Study of Image Authentication Technique Based on Fixed Point of Regular Stochastic Matrix." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/81525070563001864625.
Full text國立中興大學
資訊管理學系所
99
In the recently years, the whole world has gradually toward the IT society , the rapid development of network technology and image processing also are getting mature, the electronic products is commonly used in daily life, such as: computers, mobile phones, digital cameras, etc., those device are all with a lot of digital images, even in the real life, there exist many established photographs, graphics, pictures, logos, etc., also can be transformed by digital device into digital images, so that many digital media such as image, audio, video...etc., becomes easy to obtain or exchange over the Internet. As the result, the digital images may be tampered for specific purposes without the permission from original authors by attacker. So, this kind of behavior seriously to hurt the ownership of original authors and the accuracy of digital image. Therefore, based on the security requirements of digital image during the transmission time in the network, this paper, we proposed a fragile watermarked technique based on the fixed point of regular stochastic matrices in Markov chain to achieve the purpose of image authentication that not only can determine the correctness of digital image, but also to locate the tampered region in the image. If the digital image is tampered, we also can evaluate the integrity of tampered region to judge the truthfulness of image content. The concept of image authentication is to generate authentication data from the original image as a watermark, and then it is embedded into the original image for ensure the originality of image. Besides, in our method with the property of produce an amount of authentication data, so not only can verify the digital image integrity, but also can to locate the tampered region of the image to protect and identify the image originality, and with our image authentication method, the high quality image feature data can be embedded into image more times for recover the tampered region to make the possibility of recover tampered region is increased. In our experiment, we will show you some instance about how to combine feature extraction technique for recover tampered region in whole image. The main purpose of image authentication is that to detect whether an image has been altered or not, but sometimes, in order to increase the visibility of digital images, adjusted the brightness of image is necessary approach at sometimes, if the brightness adjustment is not too large, human eyes is difficult to aware the differences among with original image, for this reason, brightness adjustment is a legal manipulation for us, so we should improve our image authentication method and make some adjustments to develop a strategy for increase some tolerate ability for adjusted brightness situation in our image authentication method.
李玟娟. "Nano-confined crystallization of block copolymers:crystallization in the microdomain structure fixed by a crosslinked matrix." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/55407843730331233479.
Full text國立清華大學
化學工程學系
89
Abstract We studied the crystallization kinetics and crystalline morphology of poly(ethylene oxide)-block-poly(1,4-butadiene) (PEO-b-PB) exhibiting various mesophase structures in the melt. In order to establish a proper model system in which the crystallization can be effective confined within the nano-scaled microdomains while maintaining high degree of crystallizability of the crystalline blocks, the amorphous PB blocks in PB-b-PEO were crosslinked by a photo-initiated crosslinking reaction so that the crystallization-induced disruption of microdomain structure may be effectively avoided. Small angle X-ray scattering (SAXS) results revealed that the microdomain morphology in the melt effectively preserved upon crystallization of the PEO block after the PB matrix crosslinked. The kinetics of the crystallization confined in the microdomains displayed a parallel transition with the transformation of microdomain morphology. Such a distinct correlation stemmed largely from the homogeneous nucleation controlled crystallizations where the direct proportionality between nucleation rate and microdomain volume rendered the basis for the direct correlation. The homogeneous nucleation controlled crystallizations in the compositions containing cylindrical and spherical PEO microdomains was further verified from the isothermal crystallization study. In spite of the effective confinement imposed by the crosslinked PB phase, crystallization in the lamellar phase still proceeded through a mechanism analogous to the spherulitic crystallization of homopolymer.
Liu, Ken-Tzu, and 劉耕孜. "A Study of Image Authentication Technique by Applying Fixed Point of Regular Stochastic Matrix on DCT." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/42550577353167126383.
Full text國立中興大學
資訊管理學系所
102
In this paper, we propose a novel method of robust, high accuracy image tampering detection. By using the idea of fixed points extracted from a DCT (Discrete Cosine Transform) coefficient matrix from the field of stochastic matrices, we can modify this fixed point and render it an image’s authentication code. The authentication code can be used to detect tampering and locate the suspected region under our cross-examination procedure. Moreover, when the image is modified, even by slight brightness adjustment and widely used, lossy JPEG compression, our method is significantly good at detecting the tampered image regions. In this experiment, the results show that our proposed method is able to detect and locate the tampered image regions precisely and robustly against brightness adjustments and the JPEG compressions. Our method works quite well even when the watermarked image has been JPEG-compressed twice. Besides, a new idea of digital document authentication is proposed. We apply the characteristics of the Markov chain to document authentication. This concept which combines document authentication and image processing is able to authenticate the document and also remain the same document size.
Hsieh, Chao-Han, and 謝昭漢. "mRNA expressions of matrix metalloproteinases and tissue inhibitor metalloproteinases on formalin fixed paraffin embedded human breast tumor tissues using RT-PCR." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/t3uet5.
Full text國立中興大學
動物科學系所
99
Formalin fixed paraffin embedded (FFPE) is the most commonly used method worldwide for tissue storage; this resource represents a vast repository of tissue material with a long-term clinical follow-up. Although, FFPE preserves the tissue integrity it may cause extensive damage to nucleic acids stored within the tissue. Hence, the primary goal of this experiment is to set up the best condition for detecting mRNA expression in FFPE tissues by RT-PCR. To optimize the RT-PCR condition, we compare the GAPDH mRNA expression in fresh frozen tissues and tissues with formalin fixation for 1, 2 and 3 days under different proteinase K reaction time, primer concentration, commercial RT kits, amplicon size of primer treatment. We concluded that a shorten fixation time to less than one day, and extended proteinase K reaction time to 24 hours produced better RNA quality and recovery. The appropriate primer amplicon size is smaller than 100 bp and the concentration of primer is better at 5 μM in 1.5 μl. Biomi Biotech RT kit is more sensitive than Invitrogen Superscript RT kit in detecting small amplicon size primer. Matrix metalloproteinases (MMPs) can degrade extracellular matrix, which is regulated by tissue inhibitors of metalloproteinases (TIMPs). Hence, those two factors are considered to play an important role in cancer metastasis and invasion. We applied the above optimal condition for RT-PCR to measure the RNA expressions of matrix metalloproteinases (MMP) -2, -9, -14 and tissue inhibitor of metalloproteinases (TIMP) -1, -2 on FFPE human breast cancer tissues. Thirty cases of FFPE human breast tumor from 2009 and two cases of FFPE human breast tumor from 2007 were adopted in this experiment. FFPE of eleven cases of intraductal papilloma (IP), eleven cases of ductal carcinoma in situ (DCIS), and ten cases of invasive ductal carcinoma (IDC) were included in current study. The RT-PCR results were quantified. The statistics of the results show that RNA expressions of MMP-9 and TIMP-2 were significantly lower in DCIS. TIMP-1 RNA expression was not detected in all samples studied. Correlation analysis show that the expression between MMP-2 and MMP-9, MMP-2 and TIMP-2, MMP-9 and TIMP-2 are highly related. The correlation analysis of MMP-2, MMP-9, MMP-14 and TIMP-2 are highly related in DCIS. Our results suggest that MMP-2, MMP-14 and TIMP-2 are important in extracellular matrix degradation in DCIS and MMP-9 is more relevant with invasive ductal carcinoma.
Satak, Neha. "Design, Development And Flight Control Of Sapthami - A Fixed Wing Micro Air Vehicle." Thesis, 2008. http://hdl.handle.net/2005/872.
Full textSchönherr, Marek. "Improving predictions for collider observables by consistently combining fixed order calculations with resummed results in perturbation theory." Doctoral thesis, 2011. https://tud.qucosa.de/id/qucosa%3A25914.
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