Made available in DSpace on 2014-10-09T12:35:50Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:03:40Z (GMT). No. of bitstreams: 0 / A perfilagem de colunas por raios gama (column gamma scan) é uma técnica nuclear empregada para solucionar problemas em equipamentos de processos industriais, nas refinarias e petroquímicas. Consiste na utilização de uma fonte selada e um detector de radiação [NaI(Tl)], obtendo-se o perfil de densidade unidimensional (1D) do equipamento. Nas últimas décadas, ocorreram algumas melhorias na técnica de perfilagem, tais como, na digitalização contínua das informações e nos sistemas de detecção da radiação (wireless). Novos aplicativos melhoraram a qualidade da apresentação dos resultados. Entretanto, a condição da técnica não mudou drasticamente, desde sua criação. Seu resultado é simplesmente um gráfico 1D da densidade média, em função da altura do equipamento industrial. A tecnologia inovadora proposta neste trabalho de Mestrado utiliza a reconstrução tomográfica industrial, via algoritmos iterativos derivados da ART (Algebraic Reconstruction Technique) e do MART (Multiplicative Algebraic Reconstruction Technique), para apresentar o resultado de perfilagem como uma imagem bidimensional (2D) da distribuição de densidade, ao invés de um gráfico 1D. Nitidamente, uma imagem 2D possui mais informações técnicas do equipamento em análise, permitindo um avanço na tecnologia de ensaios não destrutivos (END). Assim, muitos problemas operacionais não detectáveis em equipamentos de processos industriais podem ser descobertos e solucionados de forma on-line, usando-se o imageamento 2D. Esta tecnologia permitiu que um pedido de patente fosse depositado junto ao Instituto Nacional de Propriedade Industrial (INPI). / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Made available in DSpace on 2014-10-09T12:40:53Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:17Z (GMT). No. of bitstreams: 1 02953.pdf: 10337836 bytes, checksum: 9de56156c1135dba861ce367dcc48691 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Robotics and Automation field is booming in today´s scenario. Researchers and Technologist comes up with new ideas in the robotics field to achieve a higher productivity, flexibility and efficiency. To achieve the above goals, it shall be required that human and robot share their work space with each other and works in a collaborative nature. Safety is a main concern and in focus. Robot should not injure the operator in any way during working in robotic cell. In this master thesis main focus is to create a various test plans and validate them to ensure the safety level in robotic cell. The test plan should be validated in a real robot environment. The test plans consist of functional and individual verification of safety devices which are being used in a robotic cell at PTC which is known as smart automation lab. Apart from that it includes design simulation of robotic cells with manikins to ensure validation of safety in virtual environment. Design simulation of robotic cell with manikins are created in RobotStudio 6.06. However, smart components, trap routines, SafeMove and offline program in RAPID have been created. Various test results are incorporated in the results section to ensure the verification and validation of safe human robot collaboration of virtual environment in RobotStudio 6.06.

The master´s thesis deals with creating a usable methodology for measuring the position of kinematic points McPherson suspension using optical scanners available on ÚADI. The answer lies in comparing the measurement results obtained using the scanners ATOS and TRITOP with regard to the different measurement methods. Using analytic geometry and the software ADAMS are fixed characteristics of the suspension, they are compared with values measured on the geometry. Finally, it evaluated the accuracy of measurement methods.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Interdisciplinary Science, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / by Richard Eugene Hamilton. / M.S.

No description available.

Radiotherapy is a prominent cancer treatment modality in medicine, aiming to deliver adequate doses to the target while minimizing harm to healthy tissue. Recent advancements in computer technology, machine engineering, and imaging have facilitated intricate treatment planning and accurate radiation administration. These advancements have allowed for more precise dose distributions to be delivered to cancer patients. However, even small discrepancies in setup or delivery can result in significant dose variations. While treatment planning systems provide 3D dose calculations, there is currently a lack of 3D measurement tools in the clinic to verify the accuracy of dose calculation and delivery. Presently, medical physicists rely on 2D dose plane comparisons with treatment planning calculations using gamma index analyses. However, these results do not directly correlate with clinical dose-volume constraints, and detecting delivery errors using 1D or 2D dosimetry is challenging. The implementation of 3D dosimetry not only ensures the safety of radiation treatment but also facilitates the development of new emerging radiation treatment techniques. This study aims to commission and validate a clinically viable optical scanner for 3D dosimetry and apply the developed system to address current clinical and pre-clinical challenges, thereby advancing our understanding of treatment uncertainties in modern radiotherapy. The optical CT scanner that was developed comprises four key components: an LED illuminator, an aquarium with matching fluid, a fiber optic taper, and a CCD camera. The LED illuminator emits uniform and parallel red light at a peak wavelength of 625 nm and a full width at half maximum (FWHM) of 20 nm in continuous mode. The aquarium is constructed with transparent acrylic walls and is designed to accommodate the 3D dosimeter PRESAGE, which can be fixed on a rotation stage inside the tank. Clear acrylic has excellent optical clarity and light transmission, with a refractive index of 1.49 that is close to the average refractive index (1.54) of PRESAGE. To match the refractive index of the 3D dosimeters, a matching liquid composed of 90% Octyl Salicylate and 10% Octyl-P-Methoxy Cinnamate is filled in the tank. The fiber optic taper serves two functions: first, it demagnifies the projection images while preserving their shape, and second, it effectively reduces the acceptance angle of the light reaching the CCD camera. The CCD camera used in the system is an Allied Vision model with a resolution of 0.016 mm, capable of acquiring 2D projection images from various angles. The principle of the optical CT scanner follows that of CT imaging, where 2D projection images from different angles are used to reconstruct volumetric 3D dose images using the filtered back projection technique. To validate the dosimetric measurements and assess the uncertainties of the 3D dosimetry system, 21 benchmark experiments, including mechanical, imaging, and dosimetry tests were conducted. Furthermore, the developed system was employed for various applications, including patient-specific IMRT QA, small field dosimetry using kilovoltage and megavoltage beams, as well as end-to-end testing of stereotactic radiosurgery. A comprehensive analysis assessed uncertainties in each scanner component. Mechanical tests showed maximum uncertainties below 1%. By employing background subtraction and calibration techniques, measurement uncertainty was reduced to <1% in the optimal dose range. Background subtraction resulted in a remarkable 77% reduction in uncertainty by mitigating artifacts, ambient light, and refractive light. Reproducibility was excellent, with mean and standard deviation of dose differences below 0.4% and 1.1%, respectively, in three repeat scans. Dose distribution measurements exhibited strong agreement (passing rates: 98%-100%) between 3D measurements, treatment planning calculations, and EBT3 film dosimetry. Results confirm the optical CT scanner's robustness and accuracy for clinical 3D radiation dosimetry. The study also demonstrates that the developed 3D dosimetry system surpasses the limitations of traditional 2D gamma tests by providing clinicians with more clinically relevant information. This includes measured dose-volume histograms (DVHs) and the evaluation of gamma failing points in 3D space, enabling a comprehensive assessment of individual treatment plans. Furthermore, the study showcased the feasibility of utilizing this system to characterize a radiosurgery platform. It successfully assessed mechanical and dosimetric errors in off-axis delivery and evaluated the accuracy of treatment planning dose calculations, including modeling small fields, out-of-field dose, and multi-leaf collimator (MLC) characteristics. In addition, compelling evidence was presented that the high-resolution 3D dosimeter used in this study is capable of accurate dosimetry for both megavoltage and kilovoltage small fields. Importantly, the dosimeter exhibits no energy or dose rate dependence, further supporting its reliability and suitability for precise dosimetry measurements. The intricate and three-dimensional nature of dose distributions in modern radiotherapy necessitated the development of 3D dosimetry measurements, particularly for treatments with precise margins, such as SRS and SBRT. The newly developed 3D dosimetry system offers significant enhancements to current QA practices, delivering more clinically relevant comparison results and bolstering patient safety. Furthermore, it can be utilized for independent inspections across multiple institutions or remote dosimetry verification. Beyond its applications in clinical settings, the presented 3D dosimetry system holds the potential to expedite the development and utilization of novel radiation platforms.

The threat of cyber attacks due to improper security is a real and evolving danger. Corporate and personal data is breached and lost because of web application vulnerabilities thousands of times every year. The large number of cyber attacks can partially be attributed to the fact that web application vulnerability scanners are not used by web site administrators to scan for flaws. Web application vulnerability scanners are tools that can be used by network administrators and security experts to help prevent and detect vulnerabilities such as SQL injection, buffer overflows, cross-site scripting, malicious file execution, and session hijacking. However, these tools have been found to have flaws and limitations as well. Research has shown that web application vulnerability scanners are not capable of always detecting vulnerabilities and attack vectors, and do not give effective measurements of web application security. This research presents a method to analyze the flaws and limitations of several of the most popular commercial and free/open-source web application scanners by using a secure and insecure version of a custom-built web application. Using this described method, key improvements that should be made to web application scanner techniques to reduce the number of false-positive and false-negative results are proposed. / Master of Science

Le travail accompli dans cette thèse a consisté à construire des modèles stochastiques de deux scanners de l'Internet qui sont ZMap et Shodan. Les paquets provenant de chacun des deux scanners ont été collectés par le Laboratoire de Haute Sécurité (LHS) hébergé à Inria Nancy Grand Est, et ont été utilisés pour construire par apprentissage des chaînes de Markov cachées (HMMs). La première partie du travail consistait à modéliser l'intensité des deux scanners considérés. Nous avons cherché à savoir si l'intensité de ZMap varie en fonction du service ciblé et si les intensités des deux scanners sont comparables. Les résultats ont montré que la réponse à la première question est positive (c'est-à-dire que l'intensité de ZMap varie en fonction des ports ciblés), alors que la réponse à la deuxième question est négative. En d'autres termes, nous avons obtenu un modèle pour chaque ensemble de logs. La partie suivante du travail consistait à étudier deux autres caractéristiques des mêmes scanners : leurs mouvements spatiotemporels. Nous avons créé des ensembles d'échantillons de logs avec chacune d'elle contient une seule exécution de ZMap et Shodan. Ensuite, nous avons calculé les différences d'adresses IP ciblées consécutivement par le même scanner (c.-à-d. dans chaque échantillon), et les timestamps correspondants. Les premiers ont été utilisés pour modéliser les mouvements spatiaux, tandis que les seconds pour les mouvements temporels. Une fois que les modèles de chaînes de Markov cachées sont construites, ils ont été appliqués pour identifier les scanners d'autres ensembles de logs. Dans les deux cas, nos modèles ne sont pas capables de détecter le service ciblé, mais ils détectent correctement le scanner qui génère de nouveaux logs, avec une précision de 95% en utilisant les mouvements spatiaux et de 98% pour les mouvements temporels / The work accomplished in this PhD consisted in building stochastic models of ZMap and Shodan, respectively, two Internet-wide scanners. More in detail, packets originated by each of the two considered scanners have been collected by the High Security Lab hosted in Inria, and have been used to learn Hidden Markov Models (HMMs). The rst part of the work consisted in modeling intensity of the two considered scanners. We investigated if the intensity of ZMap varies with respect to the targeted service, and if the intensities of the two scanners are comparable. Results showed that the answer to the first question is positive (i.e., intensity of ZMap varied with respect to the targeted ports), whereas the answer to the second question is negative. In other words, we obtained a model for each set of logs. The following part of the work consisted in investigating other two features of the same scanners: their spatial and temporal movements, respectively. More in detail, we created datasets containing logs of one single execution of ZMap and Shodan, respectively. Then, we computed di erences of IP addresses consecutively targeted by the same scanner (i.e., in each sample), and of the corresponding timestamps. The former have been used to model spatial movements, whereas the latter temporal ones. Once the Hidden Markov Models are available, they have been applied to detect scanners from other sets of logs. In both cases, our models are not able to detect the targeted service, but they correctly detect the scanner that originates new logs, with an accuracy of 95% when exploiting spatial movements, and of 98% when using temporal movements

Optical microscopy is the simplest and the gold standard method adopted for the screening and subsequent diagnosis of various hematological and infectious diseases like malaria, sickle cell disease, tuberculosis etc. In addition to infectious disease diagnosis, its applications range from routine blood tests to the more sophisticated cancer biopsy sample analysis. Microscopy Tests (MTs) follow a common procedural workflow: (1) A technician prepares a smear of the given sample on a glass slide in a specific manner depending on the sample and the disease to be diagnosed; (2) The smeared slide is subsequently exposed to fixative agents and different histochemical stains specific to the diagnosis to be performed and (3) the prepared slide is then observed under a high quality bright- field bench-top microscope. An expert pathologist/cytologist is required to manually examine multiple fields-of-views of the prepared slide under appropriate magnification. Multiple re-adjustments in the focus and magnification makes the process of microscopic examination time consuming and tedious. Further, the manual intervention required in all the aforementioned steps involved in a typical MT, makes it inaccessible to rural/resource limited conditions and restricts the diagnostics to be performed by trained personnel in laboratory settings. To overcome these limitations, there has been considerable research interest in developing cost-effective systems that help in automating MTs. The work done in this thesis addresses these issues and proposes a two-step solution to the problem of affordable automation of MTs for cellular imaging and subsequent diagnostic assessment. The first step deals with the development of a low cost portable system that employs custom-built microscopy setup using o -the-shelf optical components, low cost motorized stage and camera modules to facilitate slide scanning and digital image acquisition. It incorporates a novel computational approach to generate good quality in-focus images, without the need for employing high-end precision translational stages, thereby reducing the overall system cost. The process of slide analysis for result generation is further automated by using image analysis and classification algorithms. The application of the developed platform in automating slide based quantitative detection of malaria is reported in this thesis. The second aspect of the thesis addresses the automation of slide preparation. A major factor that could influence the analysis results is the quality of the prepared smears. The feasibility of automating and standardizing the process of slide preparation using Microfluidics with appropriate surface fictionalization is explored and is demonstrated in the context of automated semen analysis. As an alternative to the mechanism of fixing the spermatozoa to the glass slide by smearing and chemical treatment with fixative, microfluidic chips pre-coated with adhesive protein are employed to capture and immobilize the cells. The subsequent histochemical staining is achieved by pumping the stains through the microfluidic device. The proof-of-principle experiments performed in this thesis demonstrate the feasibility of the developed system to provide an end-to-end cost-effective alternative solution to conventional MTs. This can further serve as an assistive tool for the pathologist or in some cases completely eliminate the manual intervention required in MTs enabling repeatability and reliability in diagnosis for clinical decision making