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O formato PDF/A como meio de preservação digital no processo de digitalização das teses e dissertações da Biblioteca Central da UFSC

Martins, Alexandre Pedron
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Trabalho de Conclusão de Curso Formato: 93 p.
PT_BR
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TCC (graduação) - Universidade Federal de Santa Catarina, Centro de Ciências da Educação, Curso de Biblioteconomia.; Este trabalho baseou-se na literatura dos processos de digitalização e da temática da preservação digital e teve como objetivo analisar a utilização do formato PDF/A inserido num processo de digitalização de documentos impressos. Fez-se uma revisão bibliográfica sobre a preservação digital e os formatos de documentos eletrônicos utilizados para armazenamento digital da informação. Descrevem-se os aspectos conceituais e técnicos da digitalização de documentos impressos. Apresenta uma comparação entre os formatos TIFF e PDF/A nas suas características técnicas e em testes realizados em diferentes configurações. Conclui que o formato PDF/A atende as necessidades de armazenamento digital de documento eletrônico e estabelece um nível de segurança para que os documentos eletrônicos possam ser acessados a longo prazo.; This work was based on the literature the digitization and digital preservation issue and aims to analyze the use of PDF/A inserted in a process of scanning paper documents. There was a review of the literature on digital preservation and electronic document formats used for storing digital information. We describe the conceptual and technical aspects of digitization of printed documents. Presents a comparison between the formats TIFF and PDF/A in its technical characteristics and tests in different settings. It concludes that the PDF/A format meets the needs of digital storage and electronic document provides a level of security for electronic documents that can be accessed over the long term.

EMB 5304 – Motores de Combustão Interna I - LRCancino - Plano Ensino Metodologia - 2015-2.pdf

LRCancino
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Plano de Aprendizagem
PT_BR
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EMB 5304 – Motores de Combustão Interna I - LRCancino - Plano Ensino Metodologia - 2015-2.pdf; EMB 5304 – Motores de Combustão Interna I - LRCancino - Plano Ensino Metodologia - 2015-2.pdf

EMB 5317 – Aerodinâmica Veicular - LRCancino - Plano Ensino Metodologia - 2015-2.pdf

LRCancino
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Plano de Aprendizagem
Relevância na Pesquisa
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EMB 5317 – Aerodinâmica Veicular - LRCancino - Plano Ensino Metodologia - 2015-2.pdf; EMB 5317 – Aerodinâmica Veicular - LRCancino - Plano Ensino Metodologia - 2015-2.pdf

EMB 5328 – Motores de Combustão Interna II - LRCancino - Plano Ensino Metodologia - 2015-2.pdf

LRCancino
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Plano de Aprendizagem
PT_BR
Relevância na Pesquisa
36.51%
EMB 5328 – Motores de Combustão Interna II - LRCancino - Plano Ensino Metodologia - 2015-2.pdf; EMB 5328 – Motores de Combustão Interna II - LRCancino - Plano Ensino Metodologia - 2015-2.pdf

Estudo comparativo entre sistemáticas de digitalização de documentos: formatos HTML e PDF

Raabe,André; Pohlmann Filho,Omer
Fonte: IBICT Publicador: IBICT
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/1998 PT
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Este artigo apresenta o resultado de experimentos realizados pelo Laboratório de Biblioteca Digital da PUCRS voltados para a captura e conversão de documentos a partir do formato tradicional (papel) para o formato digital. São apresentadas e avaliadas as principais etapas envolvidas no processo de digitalização utilizando duas sistemáticas diferentes: uma baseada na conversão para HTML; a outra baseada na geração de arquivos PDF usados pelo software Adobe Acrobat Reader. São abordados também fatores essenciais aos trabalhos de digitalização tais como tecnologias de Reconhecimento Óptico dos Caracteres (OCR) e avaliação das características do acervo a ser digitalizado. Por fim, é realizado um comparativo entre as duas sistemática estudadas, apontando pontos positivos e negativos que devem ser considerados na escolha de uma diretriz de trabalho.

Widespread receptivity to neuropeptide PDF throughout the neuronal circadian clock network of Drosophila revealed by real-time cyclic AMP imaging

Shafer, Orie T.; Kim, Dong Jo; Dunbar-Yaffe, Richard; Nikolaev, Viacheslav O.; Lohse, Martin J.; Taghert, Paul H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 24/04/2008 EN
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The neuropeptide PDF is released by sixteen clock neurons in Drosophila and helps maintain circadian activity rhythms by coordinating a network of ~150 neuronal clocks. Whether PDF acts directly on elements of this neural network remains unknown. We address this question by adapting Epac1-camps, a genetically encoded cAMP FRET sensor, for use in the living brain. We find that a subset of the PDF-expressing neurons respond to PDF with long-lasting cAMP increases, and confirm that such responses require the PDF receptor. In contrast, an unrelated Drosophila neuropeptide, DH 31, stimulates large cAMP increases in all PDF-expressing clock neurons. Thus the network of ~150 clock neurons displays widespread, though not uniform, PDF receptivity. This work introduces a sensitive means of measuring cAMP changes in a living brain with sub-cellular resolution. Specifically, it experimentally confirms the longstanding hypothesis that PDF is a direct modulator of most neurons in the Drosophila clock network.

The GABAA Receptor RDL Acts in Peptidergic PDF Neurons to Promote Sleep in Drosophila

Chung, Brian Y.; Kilman, Valerie L.; Keath, J. Russel; Pitman, Jena L.; Allada, Ravi
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
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Sleep is regulated by a circadian clock that largely times sleep and wake to occur at specific times of day and a sleep homeostat that drives sleep as a function of duration of prior wakefulness[1]. To better understand the role of the circadian clock in sleep regulation, we have been using the fruit fly Drosophila melanogaster[2]. Fruit flies display all of the core behavioral features of sleep including relative immobility, elevated arousal thresholds and homeostatic regulation[2, 3]. We assessed sleep-wake modulation by a core set of 20 circadian pacemaker neurons that express the neuropeptide PDF. We find that PDF neuron ablation, loss of pdf or its receptor pdfr results in increased sleep during the late night in light:dark (LD) conditions and more prominent increases on the first subjective day of constant darkness (DD). Flies deploy similar genetic and neurotransmitter pathways to regulate sleep as their mammalian counterparts, including GABA[4]. We find that RNAi-mediated knockdown of the GABAA receptor gene, Resistant to dieldrin (Rdl), in PDF neurons, reduced sleep consistent with a role for GABA in inhibiting PDF neuron function. Patch clamp electrophysiology reveals GABA-activated picrotoxin-sensitive chloride currents on PDF+ neurons. In addition...

Daily rhythms in locomotor circuits in Drosophila involve PDF

Pírez, Nicolás; Christmann, Bethany L.; Griffith, Leslie C.
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
EN
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The neuropeptide pigment-dispersing factor (PDF) has been studied extensively in Drosophila, and its role in circadian time-keeping has been firmly established. The role of PDF outside of the clock circuit, however, is poorly understood. A recent study suggested that PDF may act on the ellipsoid body (EB) to link the clock and sleep/activity circuits. We performed whole brain optical imaging with the fluorescence resonance energy transfer (FRET)-based cAMP sensor Epac1-camps expressed under control of the pdfR promoter to address how the clock and sleep deprivation affect the physiology of these cells. Basal cAMP levels in EB were regulated both by PDF and synaptic inputs that are controlled by the circadian clock. Acute application of PDF to the brain caused a significant, and PDF-receptor-dependent, increase in cAMP in EB cells. Application of TTX to block circuit-mediated effects of PDF increased the morning response but not the response at night, implying the existence of a temporally regulated, PDF-stimulated input that blocks cAMP generation. ACh produced both direct (TTX-insensitive) and indirect (TTX-sensitive) increases in cAMP during the day but was totally TTX-insensitive at night, indicating that ACh-stimulated inputs to the EB are suppressed at night. Sleep deprivation did not affect the cAMP responses of these cells to either PDF or ACh. These results suggest a novel role for PDF as a modulator of activity outside of the clock circuit. By elucidating the mechanisms by which the neuropeptide PDF act on its target cells...

Dual PDF Signaling Pathways Reset Clocks Via TIMELESS and Acutely Excite Target Neurons to Control Circadian Behavior

Seluzicki, Adam; Flourakis, Matthieu; Kula-Eversole, Elzbieta; Zhang, Luoying; Kilman, Valerie; Allada, Ravi
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 18/03/2014 EN
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Molecular circadian clocks are interconnected via neural networks. In Drosophila, PIGMENT-DISPERSING FACTOR (PDF) acts as a master network regulator with dual functions in synchronizing molecular oscillations between disparate PDF(+) and PDF(−) circadian pacemaker neurons and controlling pacemaker neuron output. Yet the mechanisms by which PDF functions are not clear. We demonstrate that genetic inhibition of protein kinase A (PKA) in PDF(−) clock neurons can phenocopy PDF mutants while activated PKA can partially rescue PDF receptor mutants. PKA subunit transcripts are also under clock control in non-PDF DN1p neurons. To address the core clock target of PDF, we rescued per in PDF neurons of arrhythmic per01 mutants. PDF neuron rescue induced high amplitude rhythms in the clock component TIMELESS (TIM) in per-less DN1p neurons. Complete loss of PDF or PKA inhibition also results in reduced TIM levels in non-PDF neurons of per01 flies. To address how PDF impacts pacemaker neuron output, we focally applied PDF to DN1p neurons and found that it acutely depolarizes and increases firing rates of DN1p neurons. Surprisingly, these effects are reduced in the presence of an adenylate cyclase inhibitor, yet persist in the presence of PKA inhibition. We have provided evidence for a signaling mechanism (PKA) and a molecular target (TIM) by which PDF resets and synchronizes clocks and demonstrates an acute direct excitatory effect of PDF on target neurons to control neuronal output. The identification of TIM as a target of PDF signaling suggests it is a multimodal integrator of cell autonomous clock...

E AND M CIRCADIAN PACEMAKER NEURONS USE DIFFERENT PDF RECEPTOR SIGNALOSOME COMPONENTS IN DROSOPHILA

Duvall, Laura B.; Taghert, Paul H.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/2013 EN
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We used real-time imaging to detect cAMP levels in neurons of intact fly brains to study mechanisms of circadian pacemaker synchronization by the neuropeptide PDF in Drosophila. PDF receptor (PDF-R) is expressed by both M (sLNv) and E (LNd) pacemaker sub-classes and is coupled to Gsα in both cases. We previously reported that PDF-R in M pacemakers elevates cAMP levels by activating the ortholog of mammalian Adenylate Cyclase 3 (AC3), but that AC3 disruptions had no effect on E pacemaker sensitivity to PDF. Here we show that PDF-R in E pacemakers activates a different AC isoform, AC78C, an ortholog of mammalian AC8. Knockdown of AC78C by transgenic RNAi substantially reduces, but does not completely abrogate, PDF responses in these E pacemakers. The knockdown effect is intact when restricted to mature stages, suggesting a physiological and not a development role for AC78C in E pacemakers. The AC78C phenotype is rescued by over-expression of AC78C, but not by over-expression of the rutabaga AC. AC78C over-expression does not disrupt PDF responses in these E pacemakers, and neither AC78C knockdown nor its over-expression disrupted locomotor rhythms. Finally, knockdown of two AKAPs, nervy and AKAP 200 partially reduces LNd PDF responses. These findings begin to identify the components of E pacemaker PDF-R signalosomes and indicate they are distinct from PDF-R signalosomes in M pacemakers: we propose they contain AC78C and at least one other AC.

Mmp1 Processing of the PDF Neuropeptide Regulates Circadian Structural Plasticity of Pacemaker Neurons

Depetris-Chauvin, Ana; Fernández-Gamba, Ágata; Gorostiza, E. Axel; Herrero, Anastasia; Castaño, Eduardo M.; Ceriani, M. Fernanda
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 30/10/2014 EN
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In the Drosophila brain, the neuropeptide PIGMENT DISPERSING FACTOR (PDF) is expressed in the small and large Lateral ventral neurons (LNvs) and regulates circadian locomotor behavior. Interestingly, PDF immunoreactivity at the dorsal terminals changes across the day as synaptic contacts do as a result of a remarkable remodeling of sLNv projections. Despite the relevance of this phenomenon to circuit plasticity and behavior, the underlying mechanisms remain poorly understood. In this work we provide evidence that PDF along with matrix metalloproteinases (Mmp1 and 2) are key in the control of circadian structural remodeling. Adult-specific downregulation of PDF levels per se hampers circadian axonal remodeling, as it does altering Mmp1 or Mmp2 levels within PDF neurons post-developmentally. However, only Mmp1 affects PDF immunoreactivity at the dorsal terminals and exerts a clear effect on overt behavior. In vitro analysis demonstrated that PDF is hydrolyzed by Mmp1, thereby suggesting that Mmp1 could directly terminate its biological activity. These data demonstrate that Mmp1 modulates PDF processing, which leads to daily structural remodeling and circadian behavior.

DETECTING PDF JAVASCRIPT MALWARE USING CLONE DETECTION

Karademir, SARUHAN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
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One common vector of malware is JavaScript in Adobe Acrobat (PDF) files. In this thesis, we investigate using near-miss clone detectors to find this malware. We start by collecting a set of PDF files containing JavaScript malware and a set with clean JavaScript from the VirusTotal repository. We use the NiCad clone detector to find the classes of clones in a small subset of the malicious PDF files. We evaluate how clone classes can be used to find similar malicious files in the rest of the malicious collection while avoiding files in the benign collection. Our results show that a 10% subset training set produced 75% detection of previously known malware with 0% false positives. We also used the NiCad as a pattern matcher for reflexive calls common in JavaScript malware. Our results show a 57% detection of malicious collection with no false positives. When the two experiments’ results are combined, the total coverage of malware rises to 85% and maintains 100% precision. The results are heavily affected by the third-party PDF to JavaScript extractor used. When only successfully extracted PDFs are considered, recall increases to 99% and precision remains at 100%.; Thesis (Master, Electrical & Computer Engineering) -- Queen's University...

Signaling of Pigment-Dispersing Factor (PDF) in the Madeira Cockroach Rhyparobia maderae

Wei, Hongying; Yasar, Hanzey; Funk, Nico W.; Giese, Maria; Baz, El-Sayed; Stengl, Monika
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 30/09/2014 EN
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The insect neuropeptide pigment-dispersing factor (PDF) is a functional ortholog of vasoactive intestinal polypeptide, the coupling factor of the mammalian circadian pacemaker. Despite of PDF's importance for synchronized circadian locomotor activity rhythms its signaling is not well understood. We studied PDF signaling in primary cell cultures of the accessory medulla, the circadian pacemaker of the Madeira cockroach. In Ca2+ imaging studies four types of PDF-responses were distinguished. In regularly bursting type 1 pacemakers PDF application resulted in dose-dependent long-lasting increases in Ca2+ baseline concentration and frequency of oscillating Ca2+ transients. Adenylyl cyclase antagonists prevented PDF-responses in type 1 cells, indicating that PDF signaled via elevation of intracellular cAMP levels. In contrast, in type 2 pacemakers PDF transiently raised intracellular Ca2+ levels even after blocking adenylyl cyclase activity. In patch clamp experiments the previously characterized types 1–4 could not be identified. Instead, PDF-responses were categorized according to ion channels affected. Application of PDF inhibited outward potassium or inward sodium currents, sometimes in the same neuron. In a comparison of Ca2+ imaging and patch clamp experiments we hypothesized that in type 1 cells PDF-dependent rises in cAMP concentrations block primarily outward K+ currents. Possibly...

Rol del neuropéptido PDF en la adquisición y el mantenimiento de la estructura del circuito PDF; Role of the PDF neuropeptide in the acquisition and maintenance of the PDF circuit structure

Gorostiza, Ezequiel Axel
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2013 SPA
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La ritmicidad comportamental en Drosophila es sostenida por una red neuronal que en el cerebro adulto comprende alrededor de 150 neuronas. Entre éstas, las sLNv han demostrado ser esenciales para el control de la actividad rítmica. Desde el punto de vista circadiano, las sLNv tienen dos características sobresalientes: expresan el neuropéptido PDF, y atraviesan cambios estructurales circadianos en sus terminales axonales, proceso denominado plasticidad estructural. En esta tesis estudiamos qué otros cambios ocurrían concomitantes con la plasticidad estructural. Encontramos que ésta es acompañada por aumentos en el número de sinapsis y disponibilidad de vesículas en momentos de mayor complejidad del árbol axonal, que luego caen durante la fase de menor complejidad. Además demostramos que la plasticidad estructural depende de los niveles de PDF y a raíz de este análisis descubrimos un nuevo rol para PDF durante el desarrollo de las sLNv. La arquitectura adulta de las sLNv necesita que PDF actúe sobre su postsinapsis temprano en el desarrollo larval, proceso que requiere su receptor canónico. Sin embargo, la ausencia de PDF produce defectos presinápticos evidentes luego de la metamorfosis. Comprobamos que previo a la metamorfosis la postsinapsis libera GBB...

Rol del neuropéptido PDF en la adquisición y el mantenimiento de la estructura del circuito PDF; Role of the PDF neuropeptide in the acquisition and maintenance of the PDF circuit structure

Gorostiza, Ezequiel Axel
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: Tesis Doctoral Formato: text; pdf
Publicado em //2013 ESPAñOL
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La ritmicidad comportamental en Drosophila es sostenida por una red neuronal que en el cerebro adulto comprende alrededor de 150 neuronas. Entre éstas, las sLNv han demostrado ser esenciales para el control de la actividad rítmica. Desde el punto de vista circadiano, las sLNv tienen dos características sobresalientes: expresan el neuropéptido PDF, y atraviesan cambios estructurales circadianos en sus terminales axonales, proceso denominado plasticidad estructural. En esta tesis estudiamos qué otros cambios ocurrían concomitantes con la plasticidad estructural. Encontramos que ésta es acompañada por aumentos en el número de sinapsis y disponibilidad de vesículas en momentos de mayor complejidad del árbol axonal, que luego caen durante la fase de menor complejidad. Además demostramos que la plasticidad estructural depende de los niveles de PDF y a raíz de este análisis descubrimos un nuevo rol para PDF durante el desarrollo de las sLNv. La arquitectura adulta de las sLNv necesita que PDF actúe sobre su postsinapsis temprano en el desarrollo larval, proceso que requiere su receptor canónico. Sin embargo, la ausencia de PDF produce defectos presinápticos evidentes luego de la metamorfosis. Comprobamos que previo a la metamorfosis la postsinapsis libera GBB...

Assinatura digital de arquivo pdf independente de ambiente utilizando computação distribuída.

Leão, Luís Carlos Martins
Fonte: Centro Universitário de Brasília Publicador: Centro Universitário de Brasília
Tipo: Trabalho de Conclusão de Curso
PT_BR
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36.4%
As ferramentas existentes no mercado para assinar documentos digitalmente são muito caras e não executam o procedimento de maneira distribuída, o que demanda um tempo elevado quando se deseja assinar diversos documentos. Visando solucionar esse problema, esse projeto teve como objetivo geral especificar, desenvolver e implantar sistema que permita assinar uma quantidade arbitrária de documentos PDF, utilizando computação distribuída, de tal forma que não seja possível determinar de qual máquina os recursos foram utilizados. Desenvolveu-se um protótipo denominado Assinatura Digital Distribuída, o qual fez uso de duas bibliotecas, a Computação Aritmética Simples Distribuída e a JaxFish. Para construção das bibliotecas, utilizaram-se os padrões de projeto proxy, observer, template method, state e visitor e as técnicas de programação concorrente, paralela, serialização e reflection. O protótipo foi testado na Sigma Dataserv S.A., empresa que presta serviços terceirizados de informática para o Ministério do Comércio e Indústria Exterior, mais especificamente na Coordenação Geral de Modernização e Informática da referida organização. O teste consistiu da assinatura de 15.000 documentos PDFs...

A compression algorithm for the combination of PDF sets

Carrazza, Stefano; Latorre, Jose I.; Rojo, Juan; Watt, Graeme
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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The current PDF4LHC recommendation to estimate uncertainties due to parton distribution functions (PDFs) in theoretical predictions for LHC processes involves the combination of separate predictions computed using PDF sets from different groups, each of which comprises a relatively large number of either Hessian eigenvectors or Monte Carlo (MC) replicas. While many fixed-order and parton shower programs allow the evaluation of PDF uncertainties for a single PDF set at no additional CPU cost, this feature is not universal, and moreover the a posteriori combination of the predictions using at least three different PDF sets is still required. In this work, we present a strategy for the statistical combination of individual PDF sets, based on the MC representation of Hessian sets, followed by a compression algorithm for the reduction of the number of MC replicas. We illustrate our strategy with the combination and compression of the recent NNPDF3.0, CT14 and MMHT14 NNLO PDF sets. The resulting Compressed Monte Carlo PDF (CMC-PDF) sets are validated at the level of parton luminosities and LHC inclusive cross-sections and differential distributions. We determine that around 100 replicas provide an adequate representation of the probability distribution for the original combined PDF set...

Watermarking PDF Documents using Various Representations of Self-inverting Permutations

Chroni, Maria; Nikolopoulos, Stavros D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/01/2015
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This work provides to web users copyright protection of their Portable Document Format (PDF) documents by proposing efficient and easily implementable techniques for PDF watermarking; our techniques are based on the ideas of our recently proposed watermarking techniques for software, image, and audio, expanding thus the digital objects that can be efficiently watermarked through the use of self-inverting permutations. In particular, we present various representations of a self-inverting permutation $\pi^*$ namely 1D-representation, 2D-representation, and RPG-representation, and show that theses representations can be efficiently applied to PDF watermarking. Indeed, we first present an audio-based technique for marking a PDF document $T$ by exploiting the 1D-representation of a permutation $\pi^*$, and then, since pages of a PDF document $T$ are 2D objects, we present an image-based algorithm for encoding $\pi^*$ into $T$ by first mapping the elements of $\pi^*$ into a matrix $A^*$ and then using the information stored in $A^*$ to mark invisibly specific areas of PDF document $T$. Finally, we describe a graph-based watermarking algorithm for embedding a self-inverting permutation $\pi^*$ into the document structure of a PDF file $T$ by exploiting the RPG-representation of $\pi^*$ and the structure of a PDF document. We have evaluated the embedding and extracting algorithms by testing them on various and different in characteristics PDF documents.; Comment: 17 pages...

Nonlinear random displacement and fatigue estimates using PDF transformations

Sweitzer, Karl; Ferguson, N.S.
Fonte: IX International Conference on Recent Advances in Structural Dynamics Publicador: IX International Conference on Recent Advances in Structural Dynamics
Tipo: Proceedings
EN_US
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The estimation of displacement and fatigue life of nonlinear structures subjected to random excitation presents several analysis complications that will be discussed. Recent nonlinear random vibration experiments performed at Wright Patterson Air Force Base (WPAFB) [1] have generated data that has been analyzed in the time and frequency domains to model this complicated behavior. This paper will discuss how the probability density function transform and inverse distribution function methods have been applied. Probability density function (PDF) transformations have been shown to be useful for estimating nonlinear random fatigue damage, but preliminary applications were limited [2]. Analysis of the WPAFB data has employed additional normal PDF, peak PDF and nonlinear peak PDF transformations. These PDF transforms were used to estimate rates of zero crossings and more importantly, two-dimensional rainflow matrices (RFM) of total stress. The inverse distribution function method has been shown to be very effective for estimating linear to nonlinear functional relationships. Several functional relationships of linear to nonlinear displacement and stress are presented, illustrating the method using response and peak distribution functions. Standard closed form PDF transformation methods require the linear to nonlinear functional relationships to be both differentiable and invertible. Numerical PDF transformation methods have been developed that require only differentiable functional relationships. Examples of the numerical methods will be presented for a two-step serial application of the PDF transform. Analyses of the WPAFB data and subsequent ordinary differential equation (ODE) numerical experiments with Duffing equation systems have shown that total stress peak PDFs (or 2D RFMs) can be estimated using the PDF transform method. These estimated RFMs and the resultant time to failure will be compared to estimates using the raw WPAFB experimental results.; Conference proceedings from the IX International Conference on Recent Advances in Structural Dynamics...

MEDUSA: UNA APLICACIÓN DE LA INTEGRACIÓN ENTRE PDF Y ASP.NET®

ZAPATA J.,CARLOS M.; SIERRA A.,JUAN CARLOS
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2005 ES
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El formato de Documentos Portátiles (PDF por sus siglas en inglés) se ha venido consolidando en el mundo como un estándar para la transmisión de documentos vía Web, especialmente reconocidos como sólo lectura. Sin embargo, poco se han trabajado las capacidades interactivas de dicha tecnología, en particular para la captura y transmisión de datos a un servidor. En este artículo se presenta MEDUSA, un software basado en tecnología PDF que interactúa con ASP® y ASP.NET® para el manejo de una plataforma de compras vía Web.