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1
Gustavsson, Lukas. "PDF Eagle : A PDF viewer in Qt." Thesis, Linköpings universitet, RTSLAB - Laboratoriet för realtidssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76907.
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To keep up in the rapidly changing market for smart mobile phones, newways of consuming information is needed. In this master thesis project aPortable Document Format (PDF) viewer with more features than existingPDF viewers for Symbian^3 was developed, called PDF Eagle. PDF Eaglewas implemented using the Qt framework, allowing it to be easily ported todierent platforms. PDF documents have a rich structure and to be fullycompatible with the standard and at the same time responsive enough to berun on a mobile platform is a formidable technical challenge. This reportdescribes the issues that had to be resolved all the way to a functioning "app"that was marketed on the Nokia market in October 2011 with a great success.Among the technical challenges was a way to correctly render coloured objectsin PDFs. A gradient is a way to colour an area in a PDF le. Results of testsshowed that PDF Eagle is more capable of handling gradients, shadows andencrypted PDF les compared to other mobile PDF viewers. The conclusion ofthis report is that PDF Eagle is on par with or outmatches other PDF viewerson the targeted platform. This work also shows the feasibility of incrementallydownloading the pages of a PDF le which provides a better user experienceby faster viewing.
2
Håkansson, Filip. "3D PDF." Thesis, Jönköping University, JTH, Civil Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-1341.
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This report is about Adobe Acrobat 3D and their new PDF format witch can contain 3 dimensional models that are interactive. The purpose is to find out if the program and the format work in a level that is suitable for the market. To create this PDF you need Acrobat 3D installed on your computer but it only needs Acrobat Reader 7 or 8 to open it, and the Reader is free to download on the internet.
The examination is focusing on four formats: U3D, 3DS, DWG and DXF because they are the most common in the building industry seen from the architects’ way. From a 3D model exported to these four formats they where converted to PDF in different settings to be compared in different points as information and size of the files. The result where put together in tables for an easy overview.
During the work there were no big differences between the results from the different settings noticed. The differences depended more from which format the PDF where converted from. Then the program is not that old on the market there are still some things that can be improved.
3
Radits, Markus. "The Affective PDF Reader." Thesis, Växjö University, School of Mathematics and Systems Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-7033.
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The Affective PDF Reader is a PDF Reader combined with affect recognition systems. The aim of the project is to research a way to provide the reader of a PDF with real - time visual feedback while reading the text to influence the reading experience in a positive way. The visual feedback is given in accordance to analyzed emotional states of the person reading the text - this is done by capturing and interpreting affective information with a facial expression recognition system. Further enhancements would also include analysis of voice in the computation as well as gaze tracking software to be able to use the point of gaze when rendering the visualizations.The idea of the Affective PDF Reader mainly arose in admitting that the way we read text on computers, mostly with frozen and dozed off faces, is somehow an unsatisfactory state or moreover a lonesome process and a poor communication. This work is also inspired by the significant progress and efforts in recognizing emotional states from video and audio signals and the new possibilities that arise from.The prototype system was providing visualizations of footprints in different shapes and colours which were controlled by captured facial expressions to enrich the textual content with affective information. The experience showed that visual feedback controlled by utterances of facial expressions can bring another dimension to the reading experience if the visual feedback is done in a frugal and non intrusive way and it showed that the evolvement of the users can be enhanced.
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Köbe, Rolf. "PDF - Ein überflüssiges Format?" Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800381.
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Dai, Haobing. "Malicious PDF Document Analysis." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-15466.
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With the development of network and information technology, E-mail has became increasingly popular and the society’s indispensable needs. However, virus spreading via the email are also increasing. The Email attachment, such as, PDF documents, EXE programs, can spread viruses from one computer to another computer. PDF documents are one of the widely used reading or sharing documents, and the attackers are using malicious PDF documents increasingly. In this paper, in order to detect the viruses in the PDF document, I have analyzed the file structure, document structure and objects. I select two methods PDF Scrutinizer and MDScan to scan the PDF document viruses.
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König, Ralf. "PDF in Theorie und Praxis." Universitätsbibliothek Chemnitz, 2004. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200401444.
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Šústek, Ladislav. "Nástroj pro transformace dokumentů PDF." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235951.
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Result of my diploma work is library for Java programming language. Which transform PDF to XHTML files using by open source library PDFBox and FONTBox. Final XHTML file is made by CSS style which allows its easier modification. Library extracts text, images and graphic objects from PDF.
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CANDIDO, ALESSANDRO. "THEORY PREDICTIONS FOR PDF FITTING." Doctoral thesis, Università degli Studi di Milano, 2023. https://hdl.handle.net/2434/951256.
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Parton Distribution Functions (PDF) are the theoretical object describing the colliding hadron structure, arising from the factorization property of perturbative Quantum Chromodynamics (QCD).
However, these objects encode the content of the non-perturbative dynamics of large scale QCD, and it is not currently possible to compute them from first principles with the available techniques. But their universality, that is a direct consequence of factorization, allows determining PDFs from experimental data, and use the extracted value to make predictions even for any kind of processes.
The main part of this thesis is dedicated to provide fast and reliable theory predictions to be used in a global PDF determination, developing a set of essential tools to make this process scalable and reproducible.
Furthermore, some specific early applications of the tool set are presented, leading to remarkable results regarding proton properties.
A final part is dedicated to some methodological improvements in the PDFs extraction techniques, following a novel theoretical analysis, that lead to new insights, or taking into account an alternative statistical
framework.
9
Sontag, Ralph. "HTML und PDF - Konkurrenz oder Ergänzung?" Universitätsbibliothek Chemnitz, 2001. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200100355.
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Gemeinsamer Workshop von Universitaetsrechenzentrum und Professur "Rechnernetze und verteilte Systeme" der Fakultaet fuer Informatik der TU Chemnitz.
Workshop-Thema: Mobilitaet
Eine Vielzahl von Browsern und anderen Werkzeugen
analysiert, verarbeitet, manipuliert oder erzeugt
mehr oder weniger erfolgreich HTML-Dateien.
Doch browserspezifische Erweiterungen machen den
Nutzern das Leben schwer. Die Übertragung wird
dank Firewalls, Filterfunktionen und browserspezifischen
Erweiterungen instabil. Lokal gespeicherte Dateien
vermeiden dies, erfüllen jedoch andere Wünsche des
modernen, mobilen Lerners nicht.
Der Einsatz von HTML als Zielformat in der Lehre
mit neuen Medien muß gelegentlich überdacht werden.
Ein weiterer denkbarer Kandidat ist das PDF-Format,
das durch die Einbindung von Hyperlinks, Inhaltsverzeichnissen,
Stichwortregistern und sogar Formularen viele Anforderungen
an multimediale Lehrmaterialien erfüllt.
10
Donaldson, John P. "Source fingerprinting in adobe PDF files." Thesis, Monterey, California: Naval Postgraduate School, 2013. http://hdl.handle.net/10945/38919.
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Approved for public release; distribution is unlimited.Adobe Portable Document Format (PDF) documents are increasingly used as a vector for targeted attacks. Although there exist a number of tools and methodologies for performing content-level analysis to identify unwanted or malicious behavior or characteristics in these documents, these forms of analysis are hampered by increasingly complex obfuscation techniques and usually require execution of potentially malicious code. This thesis proposes a static analysis method that uses structural elements of PDF documents to identify the tools used to generate them. This method may be used to attribute malicious PDFs to particular toolkits.
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Eriksson, Maria. "Mobile PDF Management in Web Based Applications." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-347622.
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This thesis aims to investigate and analyze the available technocal solutions for implementing a PDF document viewer in a web based application is to be used in mobile devices. There is also further discussion that explores the possibilities of instead choosing to implement a native application for such a task.
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Matheson, Tomas. "Presumed pdf modelling for turbulent spray combustion." Thesis, University of Southampton, 2016. https://eprints.soton.ac.uk/413770/.
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Souza, Alan Pinto. "Metadata extraction from scientific documents in PDF." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/108005.
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A maioria dos artigos científicos estão disponíveis no formato PDF. Este padrão permite a geracão de metadados que são inclusos dentro do documento. Porém, muitos autores não definem esta informação, fazendo esse recurso inseguro ou incompleto. Este fato tem motivado pesquisa que busca extrair metadados automaticamente. A extração automática de metadados foi classificada como uma das tarefas mais desafiadoras na área de engenharia de documentos. Este trabalho propõe Artic, um método para extração de metadados de artigos científicos que aplica um modelo probabilístico em duas camadas baseado em Conditional Random Fields. A primeira camada visa identificar as secões principais com possíveis metadados. Já a segunda camada identifica, para cada secão, o metadado correspondente. Dado um PDF contendo um artigo científico, Artic extrai título, nome dos autores, emails, afiliações e informações sobre a conferência onde o paper foi publicado. Os experimentos usaram 100 artigos de conferências variadas. Os resultados superaram a solução estado-da-arte usada como baseline, atingindo uma precisão acima de 99%.Most scientific articles are available in PDF format. The PDF standard allows the generation of metadata that is included within the document. However, many authors do not define this information, making this feature unreliable or incomplete. This fact has been motivating research which aims to extract metadata automatically. Automatic metadata extraction has been identified as one of the most challenging tasks in document engineering. This work proposes Artic, a method for metadata extraction from scientific papers which employs a two-layer probabilistic framework based on Conditional Random Fields. The first layer aims at identifying the main sections with metadata information, and the second layer finds, for each section, the corresponding metadata. Given a PDF file containing a scientific paper, Artic extracts the title, author names, emails, affiliations, and venue information. We report on experiments using 100 real papers from a variety of publishers. Our results outperformed the state-of-the-art system used as the baseline, achieving a precision of over 99%.
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Santos, André Jerónimo Martins dos. "Automatic and interactive annotation of PDF documents." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17886.
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Mestrado em Engenharia de Computadores e TelemáticaO aumento acelerado da literatura biomédica levou ao desenvolvimento de vários esforços para extrair e armazenar, de forma estruturada, a informação relativa aos conceitos e relações presentes nesses textos, oferecendo aos investigadores e clínicos um acesso rápido e fácil à informação. No entanto, este processo de "curadoria de conhecimento" é uma tarefa extremamente exaustiva, sendo cada vez mais comum o uso de ferramentas de anotação automática, fazendo uso de técnicas de mineração de texto. Apesar de já existirem sistemas de anotação bastante completos e que apresentam um alto desempenho, estes não são largamente usados pela comunidade biomédica, principalmente por serem complexos e apresentarem limitações ao nível de usabilidade. Por outro lado, o PDF tornou-se nos últimos anos num dos formatos mais populares para publicar e partilhar documentos visto poder ser apresentado exatamente da mesma maneira independentemente do sistema ou plataforma em que é acedido. A maioria das ferramentas de anotação foram principalmente desenhadas para extrair informação de texto livre, contudo hoje em dia uma grande parte da literatura biomédica é publicada e distribuída em PDF, e portanto a extração de informação de documentos PDF deve ser um ponto de foco para a comunidade de mineração de texto biomédico. O objetivo do trabalho descrito nesta dissertação foi a extensão da framework Neji, permitindo o processamento de documentos em formato PDF, e a integração dessas funcionalidades na plataforma Egas, permitindo que um utilizador possa visualizar e anotar, simultaneamente, o artigo original no formato PDF e o texto extraído deste. Os sistemas desenvolvidos apresentam bons resultados de desempenho, tanto em termos de velocidade de processamento como de representação da informação, o que também contribui para uma melhor experiência de utilizador. Além disso, apresentam várias vantagens para a comunidade de mineração de texto e curadores, permitindo a anotação direta de artigos no formato PDF e simplificando o uso e configuração destes sistemas de anotação por parte de investigadores.
The accelerated increase of the biomedical literature has led to various efforts to extract and store, in a structured way, the information related with the concepts and relations presented in those texts, providing to investigators and researchers a fast and easy access to knowledge. However, this process of “knowledge curation” is an extremely exhaustive task, being more and more common demanding the application of automatic annotation tools, that make use of text mining techniques. Even thought complete annotation systems already exist and produce high performance results, they are not widely used by the biomedical community, mainly because of their complexity and also due to some limitations in usability. On the other hand, the PDF has become in the last years one of the most popular formats for publishing and sharing documents because of it can be displayed exactly in the same way independently of the system or platform where it is accessed. The majority of annotation tools were mainly designed to extract information from raw text, although a big part of the biomedical literature is published and distributed in PDF, and thus the information extraction from PDF documents should be a focus point for the biomedical text mining community. The objective of the work described in this document is the extension of Neji framework, allowing the processing of documents in PDF format, and the integration of these features in Egas platform, allowing a user to simultaneously visualize the original article in PDF format and its extracted text. The improved and developed systems present good performing results, both in terms of processing speed and representation of the information, contributing also for a better user experience. Besides that, they present several advantages for the biomedical community, allowing the direct annotation of PDF articles and simplifying the use and configuration of these annotation systems by researchers.
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Kunz, Oliver. "PDF-Simulation von Verbrennungsvorgängen in praxisnahen Brennkammern." [S.l. : s.n.], 2003. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10790759.
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Wang, Lizhong. "PDF document search within a very large database." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-210714.
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Digital search engine, taking a search request from user and then returning a result responded to the request to the user, is indispensable for modern humans who are used to surfing the Internet. On the other hand, the digital document PDF is accepted by more and more people and becomes widely used in this day and age due to the convenience and effectiveness. It follows that, the traditional library has already started to be replaced by the digital one. Combining these two factors, a document based search engine that is able to query a digital document database with an input file is urgently needed. This thesis is a software development that aims to design and implement a prototype of such search engine, and propose latent optimization methods for Loredge. This research can be mainly divided into two categories: Prototype Development and Optimization Analysis. It involves an analytical research on sample documents provided by Loredge and a multi-perspective performance analysis. The prototype contains reading, preprocessing and similarity measurement. The reading part reads in a PDF file by using an imported Java library Apache PDFBox. The preprocessing processes the in-reading document and generates document fingerprint. The similarity measurement is the final stage that measures the similarity between the input fingerprint with all the document fingerprints in the database. The optimization analysis is to balance resource consumptions involving response time, accuracy rate and memory consumption. According to the performance analysis, the shorter the document fingerprint is, the better performance the search program presents. Moreover, a permanent feature database and a similarity based filtration mechanism are proposed to further optimize the program. This project has laid a solid foundation for further study in the document based search engine by providing a feasible prototype and enough relevant experimental data. This study figures out that the following study should mainly focuses on improving the effectiveness of the database access, which involves data entry labeling and search algorithm optimization.Digital sökmotor, som tar en sökfråga från användaren och sedan returnerar ett resultat som svarar på den begäran tillbaka till användaren, är oumbärligt för moderna människor som brukar surfa på Internet. Å andra sidan, det digitala dokumentets format PDF accepteras av fler och fler människor, och det används i stor utsträckning i denna tidsålder på grund av bekvämlighet och effektivitet. Det följer att det traditionella biblioteket redan har börjat bytas ut av det digitala biblioteket. När dessa två faktorer kombineras, framgår det att det brådskande behövs en dokumentbaserad sökmotor, som har förmåga att fråga en digital databas om en viss fil. Den här uppsatsen är en mjukvaruutveckling som syftar till att designa och implementera en prototyp av en sådan sökmotor, och föreslå relevant optimeringsmetod för Loredge. Den här undersökningen kan huvudsakligen delas in i två kategorier, prototyputveckling och optimeringsanalys. Arbeten involverar en analytisk forskning om exempeldokument som kommer från Loredge och en prestandaanalys utifrån flera perspektiv. Prototypen innehåller läsning, förbehandling och likhetsmätning. Läsningsdelen läser in en PDF-fil med hjälp av en importerad Java bibliotek, Apache PDFBox. Förbehandlingsdelen bearbetar det inlästa dokumentet och genererar ett dokumentfingeravtryck. Likhetsmätningen är det sista steget, som mäter likheten mellan det inlästa fingeravtrycket och fingeravtryck av alla dokument i Loredge databas. Målet med optimeringsanalysen är att balansera resursförbrukningen, som involverar responstid, noggrannhet och minnesförbrukning. Ju kortare ett dokuments fingeravtryck är, desto bättre prestanda visar sökprogram enligt resultat av prestandaanalysen. Dessutom föreslås en permanent databas med fingeravtryck, och en likhetsbaserad filtreringsmekanism för att ytterligare optimera sökprogrammet. Det här projektet har lagt en solid grund för vidare studier om dokumentbaserad sökmotorn, genom att tillhandahålla en genomförbar prototyp och tillräckligt relevanta experimentella data. Den här studie visar att kommande forskning bör huvudsakligen inriktas på att förbättra effektivitet i databasåtkomsten, vilken innefattar data märkning och optimering av sökalgoritm.
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Niemi, Jesper. "Evaluating and comparing tools for generating PDF files." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-345732.
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There exists many software tools for generating PDF files, some of which have advantages over others. To determine what tool is better than others is of interest when one has a choice to make between different tools; one obviously wants to pick the tool that suits the user the best. In this thesis, four different software tools for generating PDFs, LaTeX, Groff, HTMLDOC and ReportLab, are evaluated under a set of requirements and compared against each other to determine which of these tools fulfills the requirements the best. The evaluation was done by researching literature, manuals and user guides, along with practical testing to determine whether a tool fulfilled a requirement or not. The results from the evaluation and comparison are that LaTeX has clear advantages over the other tools. Thus, the conclusion of this thesis is that LaTeX should be chosen as the tool for generating PDF over Groff, HTMLDOC and ReportLab.
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Bakosi, József. "PDF modeling of turbulent flows on unstructured grids." Fairfax, VA : George Mason University, 2008. http://hdl.handle.net/1920/3083.
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Thesis (Ph.D.)--George Mason University, 2008.Vita: p. 178. Thesis director: Zafer Boybeyi. Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Computational Sciences and Informatics. Title from PDF t.p. (viewed June 30, 2008). Includes bibliographical references (p. 168-177). Also issued in print.
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Sjöholm, Peter. "The Extendable Guideline for Analysing Malicious PDF Documents." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-23192.
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Today, the average computer user has undoubtedly encountered the PDF format while handling electronic documents. Due to its wide-spread popularity and feature richness, PDF documents are commonly utilized by attackers in order to infect systems with malware. This thesis will present The Extendable Guideline for Analysing Malicious PDF Documents. This work will establish the foundation of the guideline and populate it with a part of the analysis process. The guideline relies on earlier published material in the topic. It is a practical guideline that is followed by the use of a flowchart and can be utilized by an analyst in order to determine if a PDF document is malicious or not. It provides technical background information, suitable analysis techniques, and tools. The guideline structure was developed by using sequential thinking in combination with the divide and conquer paradigm. The thesis will also elucidate commonly applied techniques that are used by malicious PDF authors in order to infect systems, evade detection, and distribute their malicious documents. A commonly utilized function in PDF documents are the JavaScript feature. There are a wide range of other features that are targeted by malicious PDF authors, but they are more rarely encountered. PDF documents are often distributed by attackers by sending them as an attachment in an email, or storing the document on a web server.
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Svoboda, Ondřej. "Webová aplikace pro fulltextové vyhledávání nad PDF dokumenty." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2012. http://www.nusl.cz/ntk/nusl-236456.
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This master's thesis describes principles of full text search engines, design and implementation of web application for referencing and full text searching in PDF documents. It also contains an overview and comparison with currently available reference management software. There are discussed bibliographic information export possibilities in various citation styles and formats. Final application is written in PHP scripting language and uses MySQL database.
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Lemire, Garlic Nicole. "NLG Thesis Appendices Final 5 12 17.pdf." Master's thesis, Temple University Libraries, 2017. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/452949.
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Media Studies & ProductionM.A.
The analysis of mainstream newspaper content has long been mined by communication scholars and researchers for insights into public opinion and perceptions. In recent years, scholars have been examining African-American authored periodicals to obtain similar insights. Hearkening back to the 1950s and 1960s civil rights movement in the United States, the highly-publicized killings of African-American men by police officers during the past several years have highlighted longstanding strained police-community relations. As part of its role as both a reflection of, and an advocate for, the African-American community, African-American journalistic texts contain a wealth of data about African-American public opinion about, and perceptions of, police. In years past, media content analysts would manually sift through newspapers to divine interesting police-related themes and variables worthy of study. But, with the exponential growth of digitized texts, communication scholars are experimenting with computerized text analysis tools like topic modeling software to aid them in their content analyses. This thesis considers to what degree topic modeling software can be used at the exploratory stage of designing a content analysis study to aid in uncovering themes and variables worthy of further investigation. Appendix A contains results of the manual exploratory content analysis. The list of topics generated by the topic modeling software may be found in Appendix B.
Temple University--Theses
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Rosén, Gustav. "Analysis of Tabula : A PDF-Table extraction tool." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-395656.
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PDF is a widely used text document format used by both the private and the public sector. It is designed to create layouts of text and figures on a virtual page. Research groups often publish reports in this format including raw data in tables. The content of PDF-tables can be difficult to extract, an issue the National Food Agency often runs into. Building a PDF-interpreter from the scratch is a complex and overwhelming task but there are plenty of available PDF-Table extractors. While none meet the specific requirements of the National Food Agency the most effective tool, Tabula, is open source. By analyzing the source code an evaluation of extending Tabula can be made to possibly meet the requirements in the future. However, the lack of documentation and poor class definitions makes the source code arduous to understand. Building a new application using the same library as Tabula appears to be a more promising approach.
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Ho, Yu-Feng. "PDF Receipts: A micro-based-payment web service." CSUSB ScholarWorks, 2004. https://scholarworks.lib.csusb.edu/etd-project/2714.
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The purpose of this project is to design, build and implement an instance of a specified online payment system, which is based on micro-payments. The three components for this system are a bookstore, a receipt service and a currency issuer.
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Wang, Yingzhuo. "PDF shopping system with the lightweight currency protocol." CSUSB ScholarWorks, 2005. https://scholarworks.lib.csusb.edu/etd-project/2820.
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This project is a web application for two types of bookstores an E-Bookstore and a PDF-Bookstore. Both are document sellers, however, The E-Bookstore is not a currency user. The PDF-Bookstore sells PDF documents and issues a lightweight currency called Scart. Customers can sell their PDF documents to earn Scart currency and buy PDF documents by paying with Scart.
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Asif, Muhammad. "Customization of Docbook to Generate PDF, HTM & CHM." Thesis, Linköping University, Department of Computer and Information Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-52484.
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Software documentation is an important aspect of software projects. Software documentation plays a key role in software
development if it is up-to-date and complete. Software documentation should have the synchronization with the software
development. One of the problems is duplication; same information is written in different documents and stored in different
places with different formats making things complex to manage. By using traditional documentation tools, it’s hard to maintain
documentation for complex systems and it is time consuming.
To overcome these problems, we have used XML Docbook that is a good solution for it. Docbook provides single sourcing
technique in which documents are written ideally in one place and can convert it into different other formats from the same
location. Actually docbook is based on xml which can be easily edited by most of the programming languages. If there are many
developers are writing documentation for their software modules then we don’t need to copy and paste all the documents into
one document to produce a complete document for the software product. We have to just add the references to all those files
that should be present in the final document and then compile it with some processors and it automatically get document
contents from all files and put it into one document, so it’s easy to handle and maintain software documentation with docbook.
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Krakhellen, Bente. "Tilgjengelighet til Word- og PDF- dokument for blinde skjermleserbrukere." Thesis, Norges teknisk-naturvitenskapelige universitet, Pedagogisk institutt, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23436.
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Formål: Formålet med denne undersøkelsen har vært å finne ut om det er forskjell på tilgjengeligheten til Word- og PDF-dokument for blinde skjermleserbrukere når dokumentene er universelt utformet. Metode: Det er benyttet en empirisk, kvantitativ metode for å finne svar på problemstillingen, og designet baserer seg på besøksintervju. Tilgjengelighetsbegrepet er splittet i to. En teknisk orientert komponent som jeg har kalt tilgang og en brukervennlighetskomponent jeg har kalt brukervennlighet. Spørreskjemaet jeg benyttet inneholdt flere praktiske oppgaver som informantene skulle løse med sine datatekniske hjelpemidler. Oppgavene ble løst i et Word-dokument og et PDF-dokument som var utformet og oppmerket i henhold til retningslinjer for tilgjengelighet. Resultatet for oppgavene i Word-dokumentet ble sammenlignet med resultatene for tilsvarende oppgaver i PDF-dokumentet. Det var totalt 19 informanter som deltok, 12 kvinner og 7 menn. Gjennomsnittsalderen var 47,9 år. Den yngste var 19 år og den eldste 70. Resultat og konklusjon: Funn fra undersøkelsen viser at det ikke er signifikante forskjeller på tilgangen til innholdet i Word- og PDF-dokumentet. Under brukervennlighet viser funn at det er sammenheng mellom hvilke metoder som benyttes, og resultatet på oppgavene i PDF-dokumentet. Funn viser også at det er sammenheng mellom hvilken metode som benyttes for å løse en oppgave, og tiden det tar å løse den. Disse funnene må tilskrives andre forhold enn tilgjengelighet. Metodene som er benyttet er en kombinasjon av kommandoer i skjermleseren, hurtigtaster i Word og Adobe Reader og bruk av navigasjonsmulighetene som ligger i Windows. Konklusjonen er derfor at det ikke er forskjell på tilgjengeligheten til Word- og PDF-dokument for blinde skjermleserbrukere når dokumentene er universelt utformet. Undersøkelsen har også vist at det ikke bare er dokumentformatet som bidrar til å gjøre elektroniske dokument utilgjengelige når de brukes sammen med hjelpemidler. Tre viktige forhold som påvirker tilgjengeligheten i alle dokumentformat er riktig utforming og oppmerking av dokumentene, at brukeren har tilstrekkelig god kompetanse på å lese elektroniske dokument med hjelpemidler og tekniske forhold ved selve hjelpemiddelet.
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Lovegrove, Will. "Advanced document analysis and automatic classification of PDF documents." Thesis, University of Nottingham, 1996. http://eprints.nottingham.ac.uk/13967/.
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This thesis explores the domain of document analysis and document classification within the PDF document environment The main focus is the creation of a document classification technique which can identify the logical class of a PDF document and so provide necessary information to document class specific algorithms (such as document understanding techniques). The thesis describes a page decomposition technique which is tailored to render the information contained in an unstructured PDF file into a set of blocks. The new technique is based on published research but contains many modifications which enable it to competently analyse the internal document model of PDF documents. A new level of document processing is presented: advanced document analysis. The aim of advanced document analysis is to extract information from the PDF file which can be used to help identify the logical class of that PDF file. A blackboard framework is used in a process of block labelling in which the blocks created from earlier segmentation techniques are classified into one of eight basic categories. The blackboard's knowledge sources are programmed to find recurring patterns amongst the document's blocks and formulate document-specific heuristics which can be used to tag those blocks. Meaningful document features are found from three information sources: a statistical evaluation of the document's esthetic components; a logical based evaluation of the labelled document blocks and an appearance based evaluation of the labelled document blocks. The features are used to train and test a neural net classification system which identifies the recurring patterns amongst these features for four basic document classes: newspapers; brochures; forms and academic documents. In summary this thesis shows that it is possible to classify a PDF document (which is logically unstructured) into a basic logical document class. This has important ramifications for document processing systems which have traditionally relied upon a priori knowledge of the logical class of the document they are processing.
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Zhu, Min. "Modelling and simulation of spray combustion with PDF methods." Thesis, University of Cambridge, 1996. https://www.repository.cam.ac.uk/handle/1810/272496.
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Dodoulas, Ilias. "Application of LES-PDF methods on turbulent reacting flows." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/30786.
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This research concerns the application of the Probability Density Function (PDF) on Large Eddy Simulations (LES) of turbulent reacting flows in a wide range of open flame configurations spanning between the premixed and non-premixed regime. The aim is to validate the applicability of the PDF model on a wide range of flames without any special treatment. Additionally, the \textit{a-posteriori} Chemical Exposive Mode Analysis (CEMA) has been applied to the results in order to examine the flame structure and identify locations of extinction, re-ignition, etc. Four different series of flames are studied, each one of them belonging to a completely different combustion regime. The F1-F3 premixed turbulent flames is the first family of flames where the PDF method is applied. The LES-PDF model is shown to accurately predict the flow field and the scalar field even on a very coarse grid. The simulations were performed on a personal computer, so the computational power was severely restricted. Nevertheless, the PDF model was able to give accurate predictions, so one of the flames was chosen for a further sensitivity analysis. A large number of modelling parameters were studied and the results show little sensitivity to them in contrast to RANS-PDF approaches in premixed flames. Finally, the model is able to capture large scale quenching at qualitatively the correct extinction speed. The Cambridge-Sandia series of swirling stratified flames was also examined. It encompasses a wide range of flames with various combinations of swirl and stratification ratio levels. Four distinct cases were selected and tested. For the most simple flames (SwB1 and SwB5), the model gives excellent prediction for both the flow field and the scalar distribution. The introduction of the additional fields improves slightly the results, especially at locations further away from the nozzle exit. For the flames which exhibit more complex flow fields and complex characteristics (SwB6 and SwB11), the model gives reasonable results, given the complexity of the flow field. The introduction of differential diffusion and heat losses towards the ceramic cap was studied independently on the SwB11 flame and was found to have counteracting effects. Therefore, their combination was tested and was found to give a significant improvement. The next series of flames is the Sydney Swirl flames. The SM1 and SM2 flames are two complex swirling flames with a difficult flow field to capture. The field is composed of recirculating zones and vortex break-down bubble areas. The SM2 has not been tested in the literature and this work is the first modelling approach. The flow field simulation results are reasonable, given the complexity of the flame. The biggest discrepancies are observed close to the nozzle exit. The Chemical Explosive Mode Analysis is also performed to give information about the flame structure. The flame is divided into three distinct zones with the second one being a very large quenching region. The CEMA analysis explains why the flame does not quench, but re-ignites further down. Finally, the Delft III premixed flame is studied, a difficult flame to model as it shows quenching with large extinction pockets despite the moderately low Reynolds number. The major flow characteristics were accurately captured by the simulation and the introduction of the additional stochastic fields improves the results close to the nozzle exit. Contrary to most researchers that model the pilot flow as a single heat source close to the nozzle exit, in this work the pilot flow is modelled as a separate flow stream, something that increased the complexity of the simulations due to the extremely thin pilot rim which was comparable to the cell size. Nevertheless, the model was able to accurately capture the localized extinction throughout the flame and the application of the Chemical Explosive Mode Analysis gave further insight into the structure of the flame.
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Fast, Ruben. "Webbapplikation för recepthantering : Konvertering av recept från PDF till databas." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Data- och elektroteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19401.
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Vahedipour, Abbas. "Application of pseudo-derivative feedback (PDF) algorithm in ship control." Thesis, University of Exeter, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277145.
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Lee, Chang-Wook. "Simulations of ignition in turbulent flows using the PDF method." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613327.
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Руденко, Олександр Борисович, Александр Борисович Руденко, Oleksandr Borysovych Rudenko, А. В. Загребельна, В. О. Колесник, and В. М. Лисянський. "Програмне забезпечення процесу створення навчальної літератури у вигляді документу pdf." Thesis, Вид-во СумДУ, 2010. http://essuir.sumdu.edu.ua/handle/123456789/5456.
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Persson, Lars Magnus. "Presumed and transported PDF methods applied to turbulent premixed flames." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/6879.
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The current study focuses on the modelling of turbulent premixed or partially premixed flames over a wide range of combustion regimes using various fuels. Opposed flows featuring fractal-generated turbulence are examined using different classes of models. The reacting case is in the flamelet regime of combustion and two-scalar joint β -bimodal presumed PDF and transported PDF approaches are applied for scalar statistics. In the isothermal case the k − ε model works comparatively well, in contrast to previous studies, while in the reacting case the second moment closures are outperforming the eddy viscosity based closures. The transported PDF approach indicates an under-prediction of the turbulent burning velocity in this flow. The latter approach is therefore applied to compute freely propagating turbulent premixed flames using comprehensive chemistry. Turbulent burning velocities are extracted and compared with experimental data. The computed cases are covering the laminar flamelet to the distributed reaction zone regime. The mixture reactivity is also varied through different fuel/air mixtures and explored in terms of the Zeldovich number. The fuel/air composition studied include fuel-lean CH4, stoichiometric CH4 and C2H6 and fuel-rich H2 mixtures. The impact of molecular transport is investigated through the inclusion of an explicit analytical formulation. A multi-scale scalar dissipation rate closure that accounts for the influence of the Da number is extended in a simple manner to include Le number effects. An industrial swirl-stabilised partially premixed fuel-rich CH4 flame is simulated at realistic gas turbine conditions using the node-based Eulerian transported PDF approach coupled with a second moment closure for the velocity field. The case is in the well stirred reactor regime and the chemical kinetics is modelled using a global reaction scheme for hydrocarbon combustion. The flow field is initialised and compared with the predictions of the two-scalar joint β-bimodal presumed PDF approach.
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Hossain, Md Maruf. "PDF Calculations of Piloted Turbulent Flames with Inhomogeneous Inlet Conditions." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14218.
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This thesis presents PDF calculations of piloted turbulent flames where the level of inhomogeneity at the inlet varies and different departures from blow-off exist. Five flames are investigated numerically to study their structure in the region where the interactions between turbulence and chemistry are high. These five flames are selected such that two comparable series exist. One series has three flames of the same bulk jet velocity but different compositional conditions at the exit plane, while the other series has the same compositional boundary conditions and increasing jet velocities such that blow-off is gradually approached. The studied burner has been modified from the standard configuration with the addition of a central tube carrying methane fuel that can slide within the outer tube carrying air to induce the compositional inhomogeneity at the burner exit plane. A transport equation for the composition PDF is solved using the Lagrangian particle-based Monte Carlo method in FLUENT 14.5 commercial code by ANSYS to facilitate the implementation of detailed chemical kinetics. The code solves the Reynolds Averaged Navier Stokes (RANS) equations for the mean conservation of mass, momentum, and energy. Numerically accurate solutions are obtained after significant testing. In this regard sensitivity studies for numerical and modeling parameters such as grid convergence, turbulence model and modeling constant, mixing model and mixing model constant, number of particles per cell, ISAT error tolerance, etc. have been conducted. According to the sensitivity studies further calculations were performed using k-ε turbulence model with standard constants except for c_ɛ1 of 1.6 since this is deemed to yield the appropriate rate of dissipation of kinetic energy and better spreading rates for circular jets. Species composition is accounted for using a transport equation for the composition PDF which is coupled and solved using the Lagrangian particle-based Monte Carlo method. Twenty particles per cell were used throughout the calculations. The reduced chemical mechanism DRM22 with 24 species and 104 reactions is employed in the calculation using the In-Situ-Adaptive Tabulation (ISAT) method with an error tolerance of 1e-5. The Euclidean Minimum Spanning Tree (EMST) mixing model is used with a mixing constant Cφ =1.5 which was found to be most appropriate for the piloted jet flames considered here. Extensive comparisons between the predictions and the experimental measurements are made. The flame structures are adequately predicted, but additional developments are needed to enable the computation of the mixed-modes of combustion present in these flames.
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Flanigan, Edward. "SCALABLE TEST GENERATION FOR PATH DELAY FAULTS." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/dissertations/291.
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Modern day IC design has drawn a lot of attention towards the path delay fault model (PDF) [1], which targets delay defects that affect the timing characteristics of a circuit. Due to the exponential number of paths in modern circuits a subset of critical paths are chosen for testing purposes [2]. Path intensive circuits contain a large number of critical paths whose delays affect the performance of the circuit. This dissertation presents three techniques to improve test generation for path delay faults. The first technique presented in this dissertation avoids testing unnecessary paths by using arithmetic operations. This second technique shows how to compact many faults into a single test application, thus saving valuable test application time. The third technique demonstrates how to generate tests under modern day scan architectures. Experimental results demonstrate the effectiveness of the proposed techniques.
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Hardy, Matthew R. B. "Combining structure and appearance in digital documents using XML and PDF." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403499.
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SOUZA, OBERDAN MIGUEL RODRIGUES DE. "PRESUMED PDF MODEL WITH TABULATED CHEMICAL KINETIC APPLIED FOR SPRAY COMBUSTION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=30283@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Neste trabalho, foi desenvolvida uma modificação do modelo para simulação de sprays Diesel com o método de PDF presumida e cinética química tabulada. Através do acoplamento entre a parte química e a parte turbulenta, avaliou-se os efeitos do spray com a metodologia flamelet. Onde o conceito flamelet trata a chama difusiva e transiente como um conjunto de chamas unidimensionais, utilizando o modelo de PDF presumida para a avaliação dos valores turbulentos. A validação do modelo foi realizada com dados experimentais do laboratório Sandia, em uma câmara a volume constante. A validação e a aplicação do modelo foram conduzidas em diferentes tipos de ensaios experimentais: avaliação e comparação para diferentes modelos de cinética química do n-heptano, validação do método para o modelo de turbulência K-epsilon na câmara de volume constante do Sandia para o n-heptano não reativo, validação e comparação do modelo para o spray reativo e aplicação de modelo para o estudo comprimento do ancoramento de chama e para o tempo de atraso de ignição do n-heptano para diferentes temperaturas ambientes. Em geral, a modelagem proposta tem demonstrado excelente capacidade de previsão para a combustão com spray Diesel numa vasta gama de aplicações e é um candidato altamente promissor para outras aplicações em motores Diesel.
In this work, a modification of the model for the simulation of diesel sprays with the presumed PDF method and tabulated chemical kinetics was developed. Through the coupling between the chemical part and the turbulent part, the effects of the spray were evaluated for the flamelet methodology. Where the textit flamelet concept treats the diffusive and transient flame as a set of one-dimensional flames, using the presumed PDF model for the evaluation of turbulent values. The validation of the model was performed with experimental data from the Sandia laboratory, in a chamber at constant volume. The validation and application of the model were conducted in different types of experimental trials: evaluation and comparison for different chemical kinetics models of n-heptane, validation of the method for the turbulence model K-epsilon in the constant volume chamber of the Sandia for non-reactive n-heptane, validation and comparison of the model for the reactive spray and model application for the study of the flame anchoring length and for the ignition delay time of n-heptane at different ambient temperatures. In general, the proposed modeling has demonstrated excellent predictive capacity for diesel spray combustion in a wide range of applications and is a highly promising candidate for other applications in diesel engines.
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Азарова, А. О., and Я. В. Чайковська. "Метод захисту процесів електронного врядування шляхом квантування." Thesis, ВНТУ, 2019. http://ir.lib.vntu.edu.ua//handle/123456789/24192.
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В роботі розглянуто та детально проаналізовано вразливість стеганографічних алгоритмів вбудовування цифрових водяних знаків в PDF файли, а саме на основі квантування.The paper considers and analyzes in detail the vulnerability of the steganographic algorithms for embedding digital watermarks into PDF files, in particular quantization.
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Carrazza, S. "PARTON DISTRIBUTION FUNCTIONS WITH QED CORRECTIONS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/284820.
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We present the first unbiased determination of parton distribution functions (PDFs) with electroweak corrections. The aim of this thesis is to provide an exhaustive description of the theoretical framework and the technical implementation which leads to the determination of a set of PDFs which includes the photon PDF and quantum electrodynamics (QED) contributions to parton evolution. First, we introduce and motivate the need of including electroweak corrections to PDFs, providing phenomenological examples and presenting an overview of the current state of the art in PDF fits. The theoretical implications of such corrections are then described through the implementation of the combined QCDxQED evolution in APFEL, a public code for the solution of the PDF evolution developed particularly for this thesis. We proceed by presenting the new structure of the Neural-Network PDF (NNPDF) methodology used for the extraction of this set of PDFs with QED corrections. We then provide a first determination of the full set of PDFs based on deep-inelastic scattering data and LHC data for W and Z/γ* Drell-Yan production, using leading-order QED and NLO or NNLO QCD: the so-called NNPDF2.3QED set of PDFs. We perform a preliminary investigation of the phenomenological implications of NNPDF2.3QED set, in particular, focusing on the photon-induced corrections to direct photon production at HERA, high-mass dilepton and W pair production at the LHC and finally, providing a first determination of lepton PDFs through the APFEL evolution. We conclude with a summary of the technological upgrades required for the improvement of future PDF determinations with electroweak corrections.
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Kuráňová, Silvie. "Interactive PDF Documents in Math Education Focused on Tests for Differential Equations." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-80489.
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The progress of blended learning has given rise to the need to prepare quality electronic materials, especially those which use the greatest advantage of an electronic document – its interactivity. This
paper presents several types of PDF materials – interactive exercises, tests and games created by LaTeX packages (AcroTeX eDucation Bundle) with a contribution of other supporting instruments (3D graphics, fancytooltips, AcroFLeX). Differential equations, as an important tool of continuous mathematical modeling, have been chosen to demonstrate the still increasing power of PDF documents. This strategy allowed me to introduce innovative approaches in explaining and exercising this part of mathematics at the same time. To create such materials some LaTeX knowledge is needed; nevertheless this article is for all math teachers who are looking for quality interactive materials.
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Couzinet, Anthony. "Approche PDF jointe fluide-particule pour la modélisation des écoulements turbulents diphasiques anisothermes." Phd thesis, Toulouse, INPT, 2008. http://oatao.univ-toulouse.fr/7633/1/couzinet.pdf.
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Le contexte général de cette thèse s'inscrit dans le cadre de la modélisation des écoulements turbulents à phase dispersée anisothermes. Les travaux réalisés portent sur la compréhension et la modélisation statistique des mécanismes de transport de température de particules solides dans un écoulement d'air turbulent. Des simulations numériques directes (DNS) couplées aux calculs de trajectoires, de vitesses et de températures de plusieurs dizaines de milliers de particules par simulations de particules discrètes (DPS) ont été menées pour une configuration académique de turbulence homogène isotrope soumise à un gradient de température moyen. Une base de données de simulations a été réalisée pour différentes types de particules (différentes inerties thermiques et dynamiques). Nous avons proposé un modèle Lagrangien stochastique de la turbulence de température mesurée le long de la trajectoire des particules. Ce modèle est utilisé pour fermer les équations aux moments de la phase dispersée dans le cadre de la modélisation statistique des écoulements diphasiques basée sur la fonction de densité de probabilité (pdf) jointe fluide-particule. En particulier, cette modélisation est appliquée pour notre configuration afin de prédire les flux de chaleur et la variance de température des particules. Les résultats obtenus sont confrontés aux résultats des simulations numériques.
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Edström, Alexander, and Nathalie Jangå. "Fakturahantering företag till företag : En studie kring två olika tillvägagångssätt (Post&PDF)." Thesis, Linnéuniversitetet, Institutionen för informatik (IK), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-44682.
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Att fakturera är något som alla företag måste göra för att tjäna pengar. Fakturering kan ske på flera olika sätt och det finns olika åsikter vad som är att föredra bland företag när det handlar om hantering av fakturor. Teorin menar på att använda sig av elektroniska faktureringssätt är mer effektivt än fakturering via traditionell post. Syftet med denna forskning var att ta reda på varför företag i Sverige år 2015 väljer att skicka, mottaga och hantera fakturor med post när det finns alternativa metoder som PDF via mail och vad det är som gör att företag inte byter från det ena förhållningssättet till det andra.To invoice is something that all companies must do to earn money. Invoicing can be done in several ways and there are different opinions in what is to be preferred among companies when it comes to handling invoices. However the theory argues, that the use of the electronic invoicing method is more effective than invoicing through traditional mail. The purpose of this study was to find out why companies in Sweden in 2015 choose to send, receive and manage invoices by email when there are alternative methods as PDF through email and what it is that makes companies not change from one approach to another.
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Schopflocher, Thomas P. "The representation of the scalar concentration PDF in turbulent flows as a mixture." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0013/NQ40289.pdf.
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Jorge, Leandro Silva. "Detecção de intrusão em redes de computadores com estatísticas PDF e classificadores neurais." Universidade Presbiteriana Mackenzie, 2006. http://tede.mackenzie.br/jspui/handle/tede/1435.
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Made available in DSpace on 2016-03-15T19:37:47Z (GMT). No. of bitstreams: 1
LEANDRO_JORGE_ENG.pdf: 1440194 bytes, checksum: ee0f29b7d9c5a94f4c02a4381d985780 (MD5)
Previous issue date: 2006-08-19This work is a study about architectures, methods and results on computer networks intrusion detection to avoid Denial-of-Services attacks. The main techniques used were: packet-oriented window observation, structured hierarchical processes, anomaly based network intrusion detection by monitoring several network traffic parameters simultaneously. The Probability Density Function (PDF) has been used and statistically compared it to normal behavior referenced functions using similarity metrics. The results have been combined into an anomaly status vector classified by a neural network classifier. Two data sets have been tested to measure the performance of the proposed approach: the OPNET simulations data and the DARPA98 intrusion detection evaluation data. The results showed reliable detection in DoS attacks with high accuracy and very low false alarm rates on all data sets.
Este trabalho é um estudo sobre arquiteturas, métodos e resultados na detecção de intrusão em redes de computadores, no reconhecimento de ataques de negação de serviços (DoS Denial-of-Service). As técnicas empregadas foram orientadas a pacotes, em janelas de observação, utilizando processos de detecção de intrusão hierárquicos, em múltiplas camadas, baseados em anomalias de rede, monitorando vários parâmetros de tráfego de rede simultaneamente. Foram utilizadas funções densidade de probabilidade (PDF Probability Density Functions), estatisticamente comparadas com funções de referência de comportamento normal, utilizando-se de métricas de similaridade, combinando os resultados em vetores de status de anomalias que foram classificados por rede neurais. Dois conjuntos de dados foram utilizados para testar o desempenho dos métodos adotados: dados de simulações OPNET e dados de avaliação de detecção de intrusão DARPA98. Os resultados demonstraram detecção confiável de ataques DoS com grande precisão e taxas muito baixas de alarmes falsos nos conjuntos de dados analisados.
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Haeri, S. "Hierarchical modelling of multiphase flows using fully resolved fixed mesh and PDF approaches." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/348830/.
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Fully–resolved simulations of multiphase flow phenomena and in particular particulate flow simulations are computationally expensive and are only feasible on massively parallel computer clusters. A 3D SIMPLE type pressure correction algorithm is implemented and extensively tested and parallelized to exploit the power of massively parallel computing clusters currently available. Domain decomposition and communication schemes applicable to a general unstructured or structured multi–block CFD codes are discussed and algorithms are proposed, implemented and tested. Several high–performance linear solvers and a multi–grid strategy for the current framework are implemented and the best types of solvers are identified. A 2D CFD code is developed by the author to test several possible fixed–mesh strategies. Variations of immersed boundary (IB) and fictitious domain (FD) methods are implemented and compared. FD methods are identified to have better properties especially if other transport phenomena are also considered. Therefore an FD method is adapted by the author for the SIMPLE type flow solvers and is extended to heat transfer problems. The method is extensively tested for the simulation of flow around stationary in addition to freely moving particles and forced motion where both natural and forced convection are considered. The method is used to study the flow and heat transfer around a stationary cylinder and a new high resolution correlation is devised for the estimation of the local Nusselt number curves. Free fall problem for a single circular cylinder is considered and the effects of internal heat generation and also long term behavior of single cold particle subject to natural convection are also studied in detail. A particle collision strategy is also adapted and tested for the particle–particle collision problems. The FD algorithm is extended to the 3D framework and the flow around single stationary sphere and also free fall of a single sphere are used to validate the FD algorithm in 3D. A unique polydispersed fluid-particle turbulent modelling process is reviewed and the closure problem for this framework is studied in detail. Two methods for the closure of the non–integer moments which results from the polydispersity of the particles are proposed namely PDF reconstruction using Laguerre polynomials and a unique direct method named Direct Fractional Method of Moments (DFMM). The latter is derived using the results of the fractional calculus by writing an equation for the fractional derivatives of the moment generating function. The proposed methods are tested on a number of problems consisting of analytical, experimental and DNS simulations to asses their validity and viability which shows that both methods provide accurate results with DFMM having more desirable properties.
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Esplund, Emil, and Elin Gosch. "Digitalisering av individuell studieplan : Från PDF till en grund för ett digitalt system." Thesis, Uppsala universitet, Institutionen för informatik och media, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-413553.
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Denna uppsats ämnar belysa om det går att digitalisera den individuella studieplanen på en institution vid Uppsala universitet. Digitalisering anses vara en av de största trenderna som påverkar dagens samhälle och det har visats bidra till ökad tillgänglighet och effektivitet inom offentlig förvaltning. Vid Uppsala universitet finns det i dagsläget behov av ett digitalt system för hanteringen av den individuella studieplanen. Studieplanen hanteras för tillfället som ett papper i form av en PDF och upplevs enligt tidigare studier, som ett mindre bra planerings- och uppföljningsverktyg. Forskningsarbetet har utförts baserat på forskningsstrategin Design & creation. Resultatet av forskningsprocessen är en informationsmodell, en processmodell i olika nivåer, samt en databas. Dessa modeller och databas är baserade på tidigare forskning, befintliga dokument och empiriskt material från intervjuer. Tidigare forskning omfattar ett verktyg för digitalisering, problem med identifierare, samt forskning kring modellering. De befintliga dokumenten utgörs av en tidigare studie om den individuella studieplan, samt lagstiftning, riktlinjer och allmän information gällande denna studieplan. Intervjuerna genomfördes med 9 informanter som använder studieplanen i sin roll på Uppsala universitet. Modellerna och databasen har utvärderats i en kriteriebaserad intervju med ämnesexpert, samt i en teoribaserad utvärdering. Forskningsresultatet tyder på att det är möjligt att digitalisera studieplanen med hjälp av de framlagda modellerna och databasen. Dessa modeller och databas kan med viss modifikation användas för att bygga ett digitalt gränssnitt och ett fullständigt system för studieplanen.This thesis aims to illustrate whether it is possible to digitize the individual study plan at an institution at Uppsala university. Digitalization is considered one of the biggest trends that affects today’s society and it has been shown to contribute to increased accessibility and efficiency in public administration. Uppsala university has a need for a digital system for the individual study plan. It is currently handled as a paper in the form of a PDF and is perceived as an inferior planning and monitoring tool, according to previous studies. The research work has been carried out based on the research strategy Design & creation. The result of the research process is an information model, a process model at different levels and a database. These models and database are based on previous research, existing documents and empirical material from interviews. Previous research includes a tool for digitalization, problems regarding identifiers and research regarding modeling. The existing documents comprise a previous study of the ISP, legislation, guidelines and general information regarding the ISP. The interviews were conducted with 9 informants who use the study plan within their role at Uppsala university. The models and database have been evaluated in a criteria-based interview with a subject matter expert and in a theory-based evaluation. The research results indicate that it is possible to digitize the study plan using the presented models and database. These models and database can be used with slight modifications to build a digital interface and a complete system for the ISP.
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Hatoum, Makram. "Digital watermarking for PDF documents and images : security, robustness and AI-based attack." Thesis, Bourgogne Franche-Comté, 2020. http://www.theses.fr/2020UBFCD016.
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Le développement technologique a ses avantages et ses inconvénients. Nous pouvons facilement partager et télécharger du contenu numérique en utilisant l’Internet. En outre, les utilisateurs malveillants peuvent aussi modifier, dupliquer et diffuser illégalement tout type d'informations, comme des images et des documents. Par conséquent, nous devons protéger ces contenus et arrêter les pirates. Le but de cette thèse est de protéger les documents PDF et les images en utilisant la technique de tatouage numérique Spread Transform Dither Modulation (STDM), tout en tenant compte des exigences principales de transparence, de robustesse et de sécurité.La méthode de tatouage STDM a un bon niveau de transparence et de robustesse contre les attaques de bruit. La clé principale dans cette méthode de tatouage est le vecteur de projection qui vise à diffuser le message sur un ensemble d'éléments. Cependant, un tel vecteur clé peut être estimée par des utilisateurs non autorisés en utilisant les techniques de séparation BSS (Blind Source Separation). Dans notre première contribution, nous présentons notre méthode de tatouage proposé CAR-STDM (Component Analysis Resistant-STDM), qui garantit la sécurité tout en préservant la transparence et la robustesse contre les attaques de bruit.STDM est également affecté par l'attaque FGA (Fixed Gain Attack). Dans la deuxième contribution, nous présentons notre méthode de tatouage proposé N-STDM qui résiste l'attaque FGA et améliore la robustesse contre l'attaque Additive White Gaussian Noise (AWGN), l'attaque de compression JPEG, et diversité d'attaques de filtrage et géométriques. Les expérimentations ont été menées sur des documents PDF et des images dans le domaine spatial et le domaine fréquentiel.Récemment, l’Apprentissage Profond et les Réseaux de Neurones atteints du développement et d'amélioration notable, en particulier dans le traitement d'image, la segmentation et la classification. Des modèles tels que CNN (Convolutional Neural Network) sont utilisés pour la dé-bruitage des images. CNN a une performance adéquate de dé-bruitage, et il pourrait être nocif pour les images tatouées. Dans la troisième contribution, nous présentons l'effet du FCNN (Fully Convolutional Neural Network), comme une attaque de dé-bruitage, sur les images tatouées. Les méthodes de tatouage STDM et SS (Spread Spectrum) sont utilisés durant les expérimentations pour intégrer les messages dans les images en appliquant plusieurs scénarios. Cette évaluation montre qu'un tel type d'attaque de dé-bruitage préserve la qualité de l'image tout en brisant la robustesse des méthodes de tatouages évaluésTechnological development has its pros and cons. Nowadays, we can easily share, download, and upload digital content using the Internet. Also, malicious users can illegally change, duplicate, and distribute any kind of information, such as images and documents. Therefore, we should protect such contents and arrest the perpetrator. The goal of this thesis is to protect PDF documents and images using the Spread Transform Dither Modulation (STDM), as a digital watermarking technique, while taking into consideration the main requirements of transparency, robustness, and security. STDM watermarking scheme achieved a good level of transparency and robustness against noise attacks. The key to this scheme is the projection vector that aims to spreads the embedded message over a set of cover elements. However, such a key vector can be estimated by unauthorized users using the Blind Source Separation (BSS) techniques. In our first contribution, we present our proposed CAR-STDM (Component Analysis Resistant-STDM) watermarking scheme, which guarantees security while preserving the transparency and robustness against noise attacks. STDM is also affected by the Fixed Gain Attack (FGA). In the second contribution, we present our proposed N-STDM watermarking scheme that resists the FGA attack and enhances the robustness against the Additive White Gaussian Noise (AWGN) attack, JPEG compression attack, and variety of filtering and geometric attacks. Experimentations have been conducted distinctly on PDF documents and images in the spatial domain and frequency domain. Recently, Deep Learning and Neural Networks achieved noticeable development and improvement, especially in image processing, segmentation, and classification. Diverse models such as Convolutional Neural Network (CNN) are exploited for modeling image priors for denoising. CNN has a suitable denoising performance, and it could be harmful to watermarked images. In the third contribution, we present the effect of a Fully Convolutional Neural Network (FCNN), as a denoising attack, on watermarked images. STDM and Spread Spectrum (SS) are used as watermarking schemes to embed the watermarks in the images using several scenarios. This evaluation shows that such type of denoising attack preserves the image quality while breaking the robustness of all evaluated watermarked schemes
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Lad, Bharat. "A computational method for simulating dispersed two-phase flows using the PDF approach." Thesis, Imperial College London, 2010. http://hdl.handle.net/10044/1/6030.
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The thesis presents a Probability Density Function (PDF)-derived Eulerian/Eulerian model for the prediction of dispersed two-phase (solid/gas) flows. Continuum equations for the dispersed phase are formulated from the Kinetic Model (KM) PDF transport equations. The Kinetic stresses of the dispersed phase are determined from an algebraic stress model (ASM) together with a KM-based transport equation for the fluctuating kinetic energy. The continuum equations for the continuous phase are assumed to be the same as those in the Eulerian two-fluid model except for the interfacial momentum and energy transfer terms. Closures for these terms are derived from the PDF KM and mirror their counterparts in the dispersed phase equations. Also, the carrier phase turbulence is modelled by the standard k-ε model. These transport equations are solved using the numerical framework of an existing two-fluid approach. Furthermore, the current two-fluid model practice of applying wall functions to impose boundary conditions is adapted for application to the particulate phase. Such wall functions are calculated from the PDF KM itself. In this approach, the PDF equations are pre-integrated using the fully developed flow assumption along the wall to relate wall fluxes to values of the relevant variables in the interior of the flow. Such integration is utilised to create a wall functions database for a range of mean flow conditions. The model is validated against a range of both unbounded and bounded flow cases. Comparisons are made with experimental data as well as the results of other computational methods. It was found that the proposed model performs very well in capturing particulate behaviour and improves, in certain aspects, on the performance of traditional two-fluid models while retaining the practicality of the latter model for industrial applications. In particular, a reasonable capture of the particulate dispersion was observed within jet flows. Improvements were also seen in the prediction of mass flux distribution in shear layers and an accurate capture of near-wall mass distributions in bounded flows.
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Xue, Furong. "Automatic semantic header generator for PDF documents." Thesis, 2003. http://spectrum.library.concordia.ca/2364/1/MQ91140.pdf.
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The Concordia INdexing and DIscovery system (CINDI) is an information discovery and retrieval system to enable a reader to discover resources from a bibliographic database. It uses a metadata description called semantic header to describe an information resource, whose content includes title, author name, the subject and sub-subject, etc. Automatic Semantic Header Generator (ASHG) is used to generate a draft version of the semantic header from a resource automatically. The existing system can deal with four special document formats: HTML, TEXT, LATEX, and RTF. Since more and more people use PDF for document exchange, perusal on line or in print format due to PDF document's easy to use and cross platform portability, more documents are published in PDF format. This thesis presents the design and implementation of an extension to the existing ASHG to extract the semantic header from a PDF document automatically. First, the PDF document is converted to plain text file using Xpdf, an open source software. Modification to Xpdf has been made to get better results of the conversion. In order to test the accuracy of the ASHG, 500 articles which are all from computer science field are used in an experiment to generate the semantic header; the results 80% accurate respectively. However the results reveal that the subject classification (about 41%) is the weakest point of ASHG and requiring further work.