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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Análise do processo de conformação de chapas utilizando simulação computacional e engenharia reversa como ferramentas integradas no desenvolvimento e construção de estampos automotivos. / Sheet metal forming process analysis using computer simulation and reverse engineering as integrated tools in automotives stamping design and construction.

Gleiton Luiz Damoulis 05 October 2010 (has links)
Em anos recentes, os processos de conformação de chapas automotivas têm sido drasticamente modificados. A utilização de equipamentos de medição metrológicos óticos sem contato e respectivos softwares baseados em fotogrametria, bem como o uso de programas de simulação de estampagem baseados no Método dos Elementos Finitos (FEM), estão se tornando uma rotina no desenvolvimento de ferramentais de estampagem, visto que a confiabilidade, precisão de resultados e facilidade de uso em relação à topologia superficial do ferramental, representou um grande salto tecnológico. Entretanto, por maior que tenha sido o avanço, persistem ainda problemas relacionados ao custo benefício quanto à adoção de certas técnicas e a possibilidade de utilizar ambos os sistemas de forma a um complementar o outro. Neste sentido, o objetivo desta tese é analisar o processo de conformação de chapas utilizando simulação computacional e engenharia reversa como ferramentas integradas no desenvolvimento e construção de estampos automotivos. São descritos casos industriais, cujos resultados demonstram que novas técnicas podem ser aplicadas na definição e modelagem do processo de estampagem de chapas metálicas, utilizando a metrologia ótica, engenharia reversa e a simulação computacional baseada no Método dos Elementos Finitos. / In recently years, sheet metal forming processes used in automotive industry have been drastically modified. The use of non-contact measurement devices based on optical metrology and respective software based on photogrammetry, and the use of stamping simulation programs based on Finite Element Method (FEM), are becoming a routine in the development of tools for stamping, visa that reliability, accuracy of results and ease of use, in relation to the tooling surface topology, was a major technology leap. However, although this advancement, there are still remaining problems related to the cost benefit of the adoption of certain techniques, and the possibility of the use of both systems, in order to complement one another. In this sense, the aims of this thesis is to analyze the sheet metal forming process using computer simulation and reverse engineering as integrated tools in design and construction of automotive dies. Industry cases are described, whose results show that new techniques can be applied in definition and modeling of stamping metal sheets process, using optical metrology, reverse engineering and computer simulation based on Finite Element Method.
322

Conjunto de procedimentos de engenharia reversa para projeto de banco de dados espaciais / Set of reverse engineering procedures for spatial database design

Matté, Lia Cláudia January 2002 (has links)
Projetos de SIG (Sistemas de Informação Geográfica), em geral, ainda não apresentam modelo conceitual de banco de dados geográficos. Os implementadores de SIG se preocupam com a aquisição dos dados (captura e adaptação), que é a etapa mais cara, e dão, ainda, pouca atenção à modelagem. A utilização de modelos conceituais faz com que os usuários controlem melhor sua base de dados e tirem maior proveito do SIG. O objetivo deste trabalho é definir um conjunto de procedimentos de engenharia reversa de bancos de dados espaciais que auxiliem na criação e manutenção de modelos conceituais para aplicações de SIG a partir de dados já existentes. Estes procedimentos podem contribuir para um aumento na qualidade dos SIG implementados, auxiliando na popularização da prática de modelagem conceitual de banco de dados geográficos. São estudados três formatos de transferência utilizados por usuários de SIG. A partir daí, é proposto uma arquitetura de sistema de engenharia reversa para SIG. / Even with the increasing use of Geographic Information Systems (GIS), conceptual modeling of geographic databases (GDB) is not yet usual among GIS professionals. This fact can in part be explained by the professional profile of most GIS designers. They usually are more familiar with specific GIS applications than with database technology. Among them, one can find cartographers, geographers, agricultural engineers, and architects. Besides that, the cost of geographic data acquisition is so high that much important is given to acquisition plans during GIS design and less interest is given to the database design process. Especially first time designers do not perceive the importance of a database schema that is independent of a specific GIS product. Conceptual design preserves the independence between data types and the logical schema of the product. Moreover, relying on the GDB conceptual schema users can better understand what part of the geographic reality is represented in the database. The main goal of this research work is to define a set of reverse engineering procedures for spatial databases that can support either creation or evolution if conceptual GDB schemas. It is expected that these procedures can enhance the quality of GDB design as well as contribute to the popularization of GDB conceptual modeling. Three different geographic data input formats to GIS are investigated and a reverse engineering system architecture for them is proposed. Resulting conceptual (sub)schemas are based on the framework GeoFrame.
323

Manufatura digital aplicada no contexto de engenharia reversa : estudo de caso : protótipo virtual do avião Blériot / Digital manufacturing applied in the context of reverse engineering : case study : a bleriot aircraft virtual prototype

Gonzalez Cardozo, Carlos Aurelio 20 August 2018 (has links)
Orientador: João Maurício Rosário / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T17:16:06Z (GMT). No. of bitstreams: 1 GonzalezCardozo_CarlosAurelio_M.pdf: 3291710 bytes, checksum: 44b69cb0622c9a8dd792e7d9b3e4cee9 (MD5) Previous issue date: 2012 / Resumo: A Manufatura Digital integra o projeto do produto ao planejamento dos processos de manufatura e de suporte ao produto. Produtos, processos e recursos são modelados a partir de dados reais, em uma fábrica virtual. O funcionamento desta fábrica virtual é testado até sua validação e os resultados são aplicados na fábrica real. É uma importante alternativa com potencial para transformar os negócios, tornando-os mais competitivos, graças aos diversos benefícios conseguidos com a Manufatura Digital, tais como redução dos ciclos de desenvolvimento do produto e dos custos de manufatura, aceleração de resposta ao mercado, aumento da qualidade do produto, melhoras na disseminação do conhecimento do produto. O objetivo deste estudo é descrever a aplicação da Manufatura Digital no Contexto de Engenharia Reversa através de um estudo de caso de um Projeto Colaborativo Internacional que resultou no Protótipo Virtual de um avião Blériot XI e fabricação de uma réplica deste avião, com o objetivo de validar a implantação da Manufatura Digital em um ambiente educacional / Abstract: The Digital Manufacturing integrates product design to manufacturing process planning and product support. Products, processes and resources are modeled from real data in a virtual factory. The operation of the virtual factory is tested to its validation and the results are applied to actual plant. It is an important alternative with the potential to transform businesses, making them more competitive, thanks to the many benefits achieved through Digital Manufacturing, such as reducing product development cycles and manufacturing cost, rapid response to market, increased product quality improvements in the dissemination of product knowledge. The aim of this study is to describe the application of Digital Manufacturing in the Context of Reverse Engineering through a case study an International Collaborative Project which resulted in the Virtual Prototype of an airplane Blériot XI and manufacture of a replica of this plane, with the aim of validating the deployment of Digital Manufacturing in an educational environment / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
324

DIM : A systematic and lightweight method for identifying dependencies between requirements

Gomez, Arturo, Rueda, Gema January 2010 (has links)
Dependencies between requirements are a crucial factor for any software development since they impact many project areas. Nevertheless, their identification remains a challenge. Some methods have been proposed but none of them are really applicable to real projects due to their high cost or low accuracy. DIM is a lightweight method for identifying dependencies proposed on a previous paper. This paper presents an experiment comparing the sets of dependencies found by DIM and a method based on pair-wise comparison. The experiment was executed using a requirement specification for an open source project. These requirements were extracted by reverse engineering. Our results have provided evidence confirming that DIM finds more dependencies and its results (the dependencies identified) do not depend on the profile of the practitioner applying it. Another important result is that DIM requires fewer resources when applied, since it does not rely on pair-wise comparisons and it can be easily automated. / Avda. Espana 101 P6 Bj-E 28341, Madrid, Spain. Telephone number: +34627770492
325

Identification d'algorithmes cryptographiques dans du code natif / Identification of cryptographic algorithms in binary programs

Lestringant, Pierre 12 December 2017 (has links)
Cette thèse traite de la conception de méthodes automatisées ou semi-automatisées pour détecter et identifier des algorithmes cryptographiques dans des programmes compilés en langage machine. La première méthode proposée a pour but l'identification de primitives symétriques. L'implémentation en langage machine d'une primitive symétrique, assimilée à une suite d'instructions, est représentée par un graphe. Sous cette forme, le code est modifié à l'aide de règles de réécriture tout en préservant une certaine notion de sémantique lors d'une phase dite de normalisation. L'objectif est de faire émerger des expressions communes à différentes implémentations d'une même primitive. Ces expressions servent alors de base à la création de signatures efficaces. La recherche de ces signatures s'effectue à l'aide d'un algorithme énumérant les isomorphismes de sous-graphe. La seconde méthode, conçue en complément de la première, produit une représentation synthétique facilitant l'identification des modes opératoires. Cette représentation se définit comme le plus petit sous-graphe préservant les distances entre des sous-ensembles de nœuds précédemment identifiés comme étant les paramètres d'entrée et de sortie des primitives impliquées. / This thesis is about the design of automatic or semi-automatic methods to detect and identify cryptographic algorithms inside programs compiled into machine code. Two methods are presented. The objective of the first method is to identify cryptographic primitives. A machine code implementation of a cryptographic primitive, regarded as a sequence of instructions, is represented by a graph structure. During a normalization phase, a set of rewrite rules is used to modify this graph representation while preserving a specific notion of semantics. The goal is to converge towards expressions which are shared across several implementations of the same primitive. We use these expressions as a basis to create efficient signatures. A subgraph isomorphism enumeration algorithm is used to search for signatures. The second method is built on top of the first one. It produces a synthetic representation designed to help in the identification of modes of operation. This synthetic representation is defined as the smallest subgraph which preserve distances between sets of vertices previously identified as the input and output parameters of the primitives involved within the mode of operation.
326

Etude de la sécurité d’algorithmes de cryptographie embarquée vis-à-vis des attaques par analyse de la consommation de courant / Study of the security of embedded cryptography algorithms facing power consumption analysis attacks

Wurcker, Antoine 23 October 2015 (has links)
La cryptographie prend une place de plus en plus importante dans la vie des sociétés depuis que ses utilisateurs se rendent compte de son importance pour sécuriser divers aspects de la vie, depuis les moyens de paiement, de communication et de sauvegarde des éléments de la vie privée des citoyens, jusqu'à la sécurité nationale des pays et de leurs armées. Depuis une vingtaine d'années on sait que les algorithmes de cryptographie ne doivent pas seulement être sûrs mathématiquement parlant, mais que leurs implémentations dans un dispositif les rendent vulnérables à d'autres menaces par des voies d'informations alternatives : les canaux auxiliaires. Que ce soit la consommation électrique, le temps ou les émissions électromagnétiques, ... ces biais ont été évalués et depuis leur découverte les recherches de nouvelles attaques et protections se succèdent afin de garantir la sécurité des algorithmes. La présente thèse s'inscrit dans ce processus et présente plusieurs travaux de recherche traitant d'attaques et de contre-mesures dans le domaine de l'exploitation de canaux auxiliaires et d'injections de fautes. Une première partie présente des contributions classiques où l'on cherche à retrouver une clef cryptographique lorsque la seconde s’attelle à un domaine moins étudié pour l'instant consistant à retrouver les spécifications d'un algorithme tenu secret. / Cryptography is taking an ever more important part in the life of societies since the users are realising the importance to secure the different aspects of life from citizens means of payment, communication and records of private life to the national securities and armies. During the last twenty years we learned that to mathematically secure cryptography algorithms is not enough because of the vulnerabilities brought by their implementations in a device through an alternative means to get information: side channels. Whether it is from power consumption, time or electromagnetic emissions ... those biases have been evaluated and, since their discovery, the researches of new attacks follow new countermeasures in order to guarantee security of algorithms. This thesis is part of this process and shows several research works about attacks and countermeasures in the fields of side channel and fault injections analysis. The first part is about classic contributions where an attacker wants to recover a secret key when the second part deals with the less studied field of secret specifications recovery.
327

Rétro-conception matérielle partielle appliquée à l'injection ciblée de fautes laser et à la détection efficace de Chevaux de Troie Matériels / Partial hardware reverse engineering applied to fine grained laser fault injection and efficient hardware trojans detection

Courbon, Franck 03 September 2015 (has links)
Le travail décrit dans cette thèse porte sur une nouvelle méthodologie de caractérisation des circuits sécurisés basée sur une rétro-conception matérielle partielle : d’une part afin d’améliorer l’injection de fautes laser, d’autre part afin de détecter la présence de Chevaux de Troie Matériels (CTMs). Notre approche est dite partielle car elle est basée sur une seule couche matérielle du composant et car elle ne vise pas à recréer une description schématique ou fonctionnelle de l’ensemble du circuit.Une méthodologie invasive de rétro-conception partielle bas coût, rapide et efficace est proposée. Elle permet d’obtenir une image globale du circuit où seule l’implémentation des caissons des transistors est visible. La mise en œuvre de cette méthodologie est appliquée sur différents circuits sécurisés. L’image obtenue selon la méthodologie déclinée précédemment est traitée afin de localiser spatialement les portes sensibles, voire critiques en matière de sécurité. Une fois ces portes sensibles identifiées, nous caractérisons l’effet du laser sur différentes parties de ces cellules de bases et nous montrons qu’il est possible de contrôler à l’aide d’injections de fautes laser la valeur contenue dans ces portes. Cette technique est inédite car elle valide le modèle de fautes sur une porte complexe en technologie 90 nm. Pour finir une méthode de détection de CTMs est proposée avec le traitement de l’image issue de la rétro-conception partielle. Nous mettons en évidence l’ajout de portes non répertoriées avec l’application sur un couple de circuits. La méthode permet donc de détecter, à moindre coût, de manière rapide et efficace la présence de CTMs. / The work described in this thesis covers an integrated circuit characterization methodology based on a partial hardware reverse engineering. On one hand in order to improve integrated circuit security characterization, on the other hand in order to detect the presence of Hardware Trojans. Our approach is said partial as it is only based on a single hardware layer of the component and also because it does not aim to recreate a schematic or functional description of the whole circuit. A low cost, fast and efficient reverse engineering methodology is proposed. The latter enables to get a global image of the circuit where only transistor's active regions are visible. It thus allows localizing every standard cell. The implementation of this methodology is applied over different secure devices. The obtained image according to the methodology declined earlier is processed in order to spatially localize sensible standard cells, nay critical in terms of security. Once these cells identified, we characterize the laser effect over different location of these standard cells and we show the possibility with the help of laser fault injection the value they contain. The technique is novel as it validates the fault model over a complex gate in 90nm technology node.Finally, a Hardware Trojan detection method is proposed using the partial reverse engineering output. We highlight the addition of few non listed cells with the application on a couple of circuits. The method implementation therefore permits to detect, without full reverse-engineering (and so cheaply), quickly and efficiently the presence of Hardware Trojans.
328

Virová analýza a reverzní inženýrství / Malware analysis and reverse engineering

Šváb, Martin January 2014 (has links)
Focus of this thesis is reverse engineering in information technology closely linked with the malware analysis. It explains fundamentals of IA-32 processors architecture and basics of operating system Microsoft Windows. Main part of this thesis is dedicated to the malware analysis, including description of creating a tool for simplification of static part of the analysis. In Conclusion various approaches to the malware analysis, which were described in previous part of the thesis, are practically demonstrated on unknown malware sample.
329

Optimisation de la transformation de matières premières issues de cultures associées légumineuse - blé tendre par une bonne connaissance de la physico-chimie des ingrédients et du procédé de fabrication / Optimization of the processing of raw materials from soft wheat - legume intercrops by a good knowledge of the physical-chemical behavior of the ingredients and of the manufacturing process.

Monnet, Anne-Flore 23 November 2018 (has links)
Le mélange blé - légumineuse constitue une option prometteuse pour le développement de pratiques agricoles durables et la fourniture de protéines de bonne qualité nutritionnelle. Des filières de transformation des cultures associées intégrant la gestion d’un mélange jusqu’à la fabrication d’un produit céréalier enrichi en farine de légumineuse pourraient être conçues. Ceci implique de maîtriser la variabilité des matières premières entrantes en seconde transformation. L’objectif de ce travail est de développer un outil permettant de maîtriser la qualité de cakes enrichis en farine de légumineuse quelles que soient les variations de qualité des matières premières, par l’utilisation du procédé de fabrication. La qualité des cakes est définie par leurs propriétés de structure aux différentes échelles. Après un travail de caractérisation des propriétés de farines variables et d’étude du procédé de fabrication, un modèle multicritère multi-contraintes de maîtrise de la qualité a été mis en place par une démarche de plan d’expériences. La capacité de prévision du modèle a été validée, et son efficacité de correction a été confirmée du point de vue instrumental et sensoriel dans le cas de deux scénarii. Après une discussion de la durabilité de la filière dans son ensemble, les connaissances acquises lors de ce travail ont été rassemblées pour formuler des recommandations vis-à-vis des étapes amont de la filière (sélection, culture, tri, 1ère transformation) dans un objectif d’ingénierie reverse. / Mixing wheat and legumes is a promising way of developing sustainable agricultural practices in addition to supplying proteins of good nutri-tional quality. Food chains for the valorization of wheat-legume intercrops could be designed to handle such a mixture right up to the production of cereal products enriched with legume flour. This would involve monitoring the variability of the raw materials used by the secondary processing industry. The aim of this work was to develop a tool to enable the monitoring of the quality of cakes enriched with legume flour regardless of variations in flour quality, by using the processing variables. The quality of soft cakes is defined by their structural properties at different length scales. After characterization of the variable properties of flour and of the manufacturing process, a multi- objective model for the monitoring of cake quality was built thanks to an optimal experimental design. The prediction capacity of the model was validated, and its correction efficiency was confirmed both instrumentally and sensorially in two case studies involving variations in the proportions and particle sizes of wheat and legume in the flour. Following a discussion of the sustainability of the food chain as a whole, the knowledge acquired during the course of this study was used to make recommen -dations concerning the upstream stages of the chain (selection, cultivation, sorting, first processing) using a reverse engineering approach.
330

Realizace ovládacího software zařízení pro měření zbytkových napětí odvrtávací metodou / Implementation of control software of device for measuring residual stresses by drilling method

Švehla, Lukáš January 2021 (has links)
The diplom thesis deals with modernization of older drill out machine MTS3000 for measurement of residual stress. To make the device work it is necessary to keep running computer control card and necessary software. Because a producer does not provide any upgrade, it was decided to put the device into operation by creating new software. At first an analysis of drilling method and function of device MTS3000 - Restan was made. Next step was to disassemble and analyze the station of the drilling device. Then the station was put into operation and modified for control via USB device NI USB 6009. Finally a computer program in LabVIEW environment was created to automate the measurement process. Program has two main tasks: one is to control the drilling cycle of the machine. Another one is to acquire data from measuring amplifier station.

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