Thèses : « LE. Scanners »

1

Lapin, O. S. « Fingerprint scanners ». Thesis, Сумський державний університет, 2012. http://essuir.sumdu.edu.ua/handle/123456789/28528.

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Bae, Kwang-Ho. « Automated registration of unorganised point clouds from terrestrial laser scanners ». Thesis, Curtin University, 2006. http://hdl.handle.net/20.500.11937/946.

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Laser scanners provide a three-dimensional sampled representation of the surfaces of objects. The spatial resolution of the data is much higher than that of conventional surveying methods. The data collected from different locations of a laser scanner must be transformed into a common coordinate system. If good a priori alignment is provided and the point clouds share a large overlapping region, existing registration methods, such as the Iterative Closest Point (ICP) or Chen and Medioni’s method, work well. In practical applications of laser scanners, partially overlapping and unorganised point clouds are provided without good initial alignment. In these cases, the existing registration methods are not appropriate since it becomes very difficult to find the correspondence of the point clouds. A registration method, the Geometric Primitive ICP with the RANSAC (GPICPR), using geometric primitives, neighbourhood search, the positional uncertainty of laser scanners, and an outlier removal procedure is proposed in this thesis. The change of geometric curvature and approximate normal vector of the surface formed by a point and its neighbourhood are used for selecting the possible correspondences of point clouds. In addition, an explicit expression of the position uncertainty of measurement by laser scanners is presented in this dissertation and this position uncertainty is utilised to estimate the precision and accuracy of the estimated relative transformation parameters between point clouds. The GP-ICPR was tested with both simulated data and datasets from close range and terrestrial laser scanners in terms of its precision, accuracy, and convergence region. It was shown that the GP-ICPR improved the precision of the estimated relative transformation parameters as much as a factor of 5.In addition, the rotational convergence region of the GP-ICPR on the order of 10°, which is much larger than the ICP or its variants, provides a window of opportunity to utilise this automated registration method in practical applications such as terrestrial surveying and deformation monitoring.

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Bae, Kwang-Ho. « Automated registration of unorganised point clouds from terrestrial laser scanners ». Curtin University of Technology, Department of Spatial Sciences, 2006. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=16596.

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Laser scanners provide a three-dimensional sampled representation of the surfaces of objects. The spatial resolution of the data is much higher than that of conventional surveying methods. The data collected from different locations of a laser scanner must be transformed into a common coordinate system. If good a priori alignment is provided and the point clouds share a large overlapping region, existing registration methods, such as the Iterative Closest Point (ICP) or Chen and Medioni’s method, work well. In practical applications of laser scanners, partially overlapping and unorganised point clouds are provided without good initial alignment. In these cases, the existing registration methods are not appropriate since it becomes very difficult to find the correspondence of the point clouds. A registration method, the Geometric Primitive ICP with the RANSAC (GPICPR), using geometric primitives, neighbourhood search, the positional uncertainty of laser scanners, and an outlier removal procedure is proposed in this thesis. The change of geometric curvature and approximate normal vector of the surface formed by a point and its neighbourhood are used for selecting the possible correspondences of point clouds. In addition, an explicit expression of the position uncertainty of measurement by laser scanners is presented in this dissertation and this position uncertainty is utilised to estimate the precision and accuracy of the estimated relative transformation parameters between point clouds. The GP-ICPR was tested with both simulated data and datasets from close range and terrestrial laser scanners in terms of its precision, accuracy, and convergence region. It was shown that the GP-ICPR improved the precision of the estimated relative transformation parameters as much as a factor of 5.
In addition, the rotational convergence region of the GP-ICPR on the order of 10°, which is much larger than the ICP or its variants, provides a window of opportunity to utilise this automated registration method in practical applications such as terrestrial surveying and deformation monitoring.

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Jagelid, Michelle. « Container Vulnerability Scanners : An Analysis ». Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279967.

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Containers are rising in popularity as a technique for deploying services to cloud infrastructures. A Container image is a static format of a running container, storing all essential information needed to boot and run a container. Container images are often stored in repositories and widely shared among users. Container images stored on registries such as Docker Hub are shown to contain numerous known vulnerabilities.‌ This study investigates differences between containers and VMs, and why security tooling, such as known-vulnerability scanners, need to adapt. Further, we present necessary steps of a workflow when implementing container vulnerability scanners, along with problems and solutions to consider for each step. Finally, a comparison was conducted of two open-source scanners, Anchore and Clair. The tools were compared on 8 versions of common OS distributions. We show that there are differences between the two tools when scanning OS-packages. A majority of these differences likely appear because of definition disagreement. Disregarding definition disagreements, other differences are more likely due to implementation, but these differences are not large enough to be significant.
Containrar är en växande teknik för användning av applikationer i moln-infrastruktur. Container-avbildningar innehåller all information om exekveringsmiljön för en container och de sparas ofta i utvecklingskataloger. Dessa avbildningar delas frekvent mellan utvecklare. Container-avbildningar som sparas i utvecklingskataloger har visats innehålla flertalet kända sårbarheter. Denna studie undersöker funktionella skillnader och design-skillnader mellan containrar och virtuella maskiner och varför säkerhetsverktyg, så som kända-sårbarhetsskannrar, behöver anpassas. Utöver detta, identifieras ett arbetsflöde som behöver implementeras vid utveckling av säkerhets-skannrar för containrar. Till detta presenteras även problem och lösningar att tänka på för varje steg i flödet. Slutligen, utförs en jämförelse mellan två skannrar med öppen källkod, nämligen Anchore och Clair. Verktygen jämförs med 8 olika versioner av vanligt förekommande operativsystem-distributioner. Resultaten visade att det finns skillnader i utförande mellan de två jämförda verktygen när man fokuserar på installerade OS-paket. Majoriteten av olikheterna är troligtvis relaterade till en oenighet av definitioner av sårbarheter. Bortser man från dessa oenigheter, uppkommer andra olikheter troligtvis på grund av skillnader i implementeringen av de två verktygen. Dessa skillnader är dock inte stora nog för att vara signifikanta.

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Kongevold, Dimitry. « Merging Meshes from Different 3D Scanners ». Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-23013.

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Creating digital representation of physical objects is becoming more and more popular as scanning technology becomes more available on the consumer marked. High precision close range scanners, based on structured light, can produce high precision meshes in short amount of time, while automated photogrammetric software can process images taken with ordinary cameras to re-create a three dimensional scenes. Unfortunately the quality of digitalization is bound to the volume of the captured scene, creating a trade of between quality and speed of acquisition. In this master thesis we present software that can merge the output of two different scanners to create a combined mesh with regions of different resolution. We propose two methods to identify corresponding regions in meshes and a variation of greedy triangulation algorithm. At the end we perform tests on combined meshes to assess the quality of merging and present the results.

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Menezes, Junior Luiz Ferreira. « Controle automatizado para scanners de luz ». [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/264979.

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Orientador: Paulo Roberto Gardel Kurka
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-04T02:13:27Z (GMT). No. of bitstreams: 1 MenezesJunior_LuizFerreira_M.pdf: 3960270 bytes, checksum: 542b501adbaca7fc3d8ff80120fab0d3 (MD5) Previous issue date: 2004
Resumo: Este trabalho apresenta um método de controle automatizado de scanners de luz baseado no posicionamento dos projetores. É desenvolvida ainda uma estratégia de posicionamento dos focos de luz, através de acionamento sincronizado por sinais de áudio. Todos os modos de controle desenvolvidos são incorporados a um software de gerenciamento. No processo de controle toma-se necessário também a construção de uma interface de dados baseada no protocolo PC-DMX512. O trabalho contempla ainda uma descrição detalhada de tal protocolo e do hardware construído. O resultado final é ilustrado através de exemplos e do manual de operação do software de controle
Abstract: The work presents a method for automatically positioning of the light beam scanners. A strategy for synchronizing their positions based on the audio signals is also developed All control modes developed are incorporated into a managing system software. The controlling process requires the construction of a digital data interface to the hardware on the basis of the DMX512 protocol. The work includes a detailed description of the DMX512 protocol and the implemented hardware. Final results are illustrated through examples and operation manual
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica

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Persson, Lucas, et Sebastian Markström. « Indoor localization of hand-held Shopping Scanners ». Thesis, KTH, Data- och elektroteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-208931.

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This thesis investigates applicable indoor navigation systems for the next generation of hand-held shopping scanners, on behalf of the company Virtual Stores. The thesis research and review applicable indoor localization methods and ways to combine and evaluate received localization data in order to provide accurate navigation without introducing any other worn equipment for a potential user. Prototype navigation systems was proposed, developed and evaluated using a combination of carefully placed radio transmitters that was used to provide radio based localization methods using Bluetooth or UltraWide Band (UWB) and inertial sensors combined with a particle filter. The Bluetooth solution was deemed incapable of providing any accurate localization method while the prototype using a combination of UWB and inertial sensors proved promising solution with below 1m average error under optimal conditions or 2.0m average localization error in a more realistic environment. However, the system requires the surveyed area to provide 3 or more UWB transmitters in the line of sight of the UWB receiver of the user at every location facing any direction to provide accurate localization. The prototype also requires to be scaled up to provide localization to more than 1 radio transmitters at the time before being introduced to the Fast moving consumer goods market.
Denna avhandling undersöker tillämpliga inomhusnavigationssystem för nästa generations handhållna shopping terminaler, på uppdrag av företaget Virtual Stores. Avhandlingen undersöker och granskar tillämpliga inomhuslokaliseringsmetoder och sätt att kombinera och utvärdera mottagna lokaliseringsdata för att bistå med ackurat navigering utan att introducera någon ytterligare utrustning för en potentiell användare. Prototypnavigationssystem föreslogs, utvecklades och utvärderades användandes en kombination av väl utplacerade radiosändare användandes Bluetooth eller UltraWide Band (UWB) och tröghetssensorer i kombination med ett partikelfilter. Bluetooth-lösningen ansågs oförmögen att tillhandahålla någon exakt lokalisering medan prototypen som använde en kombination av UWB och tröghetssensorer visade sig vara en lovande lösnings med under 1m genomsnittligt fel under optimala förhållanden eller 2,0m genomsnittligt lokaliseringsfel i mer realistisk miljö. Systemet kräver emellertid att det undersökta området tillhandahåller 3 eller fler UWB-sändare inom synfältet för UWB-mottagaren hos användaren vid varje plats och riktning för att tillhandahålla ackurat lokalisering. Prototypen behöver skalas upp för att kunna bistå med lokalisering till mer än 1 radiomottagare innan den introduceras till detaljhandlen.

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Bonjour, Philippe. « Criteres de choix des scanners a rayons x ». Aix-Marseille 2, 1990. http://www.theses.fr/1990AIX20852.

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Lee, Ki Sung. « Pragmatic image reconstruction for high resolution PET scanners / ». Thesis, Connect to this title online ; UW restricted, 2003. http://hdl.handle.net/1773/5967.

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González, Julio E. « A study of gray level recording capability for a reflective six bit desktop scanner / ». Online version of thesis, 1994. http://hdl.handle.net/1850/11289.

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Luttge, Regina. « Fabrication technologies for optical scanners based on micromachined cantilevers ». Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407826.

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Davison, Wayne. « Establishment of Accuracy Testing Facilities for Terrestrial Laser Scanners ». Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29572.

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Measurement instruments that are required for high precision and reliable work need to have regular checks to ensure they are always performing at the required level of accuracy. A Terrestrial Laser Scanner is one such instrument and with the vast amount of information that this machine is able to capture, it is especially important to run regular accuracy checks. This research is building on the work that has been done by previous researchers on the assessment of instrument accuracy and the establishment of facilities specialized for this assessment. Theoretical principles are investigated in the form of Least Squares Adjustments, similarities to panorama photography and photogrammetric accuracy. Terrestrial Laser Scanners are reviewed with respect to their scanning principles and data acquisition. The methodology incorporated in this research encompasses the positioning of targets, their survey to establish high accuracy coordinates through various methods of adjustment and thereafter the scanning of those targets. Comparisons were done using derived angles and distances between the targets to discover the point accuracy of the Laser Scanner. This was done for two facilities; a short range facility (1 to 15 meters) and a medium range facility (1 to 75 meters). The medium range facility also included a range testing baseline for distance accuracy assessments. The outcomes from the comparisons between the surveyed control data and the laser scanner observed data indicated that the laser scanner is performing below the accuracy of the surveyed data. The laser scanner was further compared against the manufacturer quoted performance specifications and revealed the laser scanner to be performing below the quoted values. The laser scanner in question showed stronger results in the horizontal measurements over the vertical measurements. All results suggested the laser scanner was delivering weak results in the vertical observations due to a mis-alignment of individual scan halves. This research was able to establish two accuracy assessment facilities specialized for Terrestrial Laser Scanners under these same conditions. Both facilities were used in conjunction, to analyze the Z+F Imager 5010C laser scanner and determine the point accuracy in terms of the observed angles and distances from this machine. The results are also able to identify errors in the performance of the laser scanner and whether or not it is performing within the manufacturer specifications by noticing any large values such as in the case of the vertical observations for this instrument.

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Hsu, Shu-Ting. « High performance micro scanners for miniature laser projection displays ». Dresden TUDpress, 2009. http://d-nb.info/996064125/04.

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CUCCIATI, GIACOMO. « Optimization and characterization of PET scanners for Medical Imaging ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2014. http://hdl.handle.net/10281/83322.

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Positron emission tomography is an imaging technique that appeared to be a valid instrument for cancers detection and neuro-imaging studies. Since first models built during 1960s, an incredible effort has been done by researchers to develop scanners more and more advanced with higher specificity and efficiency. Monte Carlo simulations have shown to be a very important tool during design phase of PET prototypes thanks to their ability to simulate systems with many coupled degrees of freedom, as it happens when particles interact with matter. This Thesis work has started in the frame the Crystal Clear Collaboration when the EndoTOFPET scanner was already under development. This prototype is an high spatial resolution scanner for the study of pancreatic carcinoma and prostatic cancer, composed by a PET head mounted on an ultrasound endoscope and a PET plate to be placed outside the body. The Collaboration has chosen to use Monte Carlo simulations to support the design of this project and two simulations toolkits were available: Geant4 and SLitrani. In this work both the toolkits are studied and ray tracing in scintillator crystals are tested. In particular photon extraction efficiency is simulated under different surface treatments as coating and wrapping. Also the influence of the crystals geometry on light output is tested simulating different scintillators sections and lengths. Both Geant4 and SLitrani have shown to give similar results under these conditions. A main issue was observed regarding secondary particles since Geant4 is able to simulate their production while it is not possible with SLitrani. On other hand crystals anisotropy for optical photons can be activated in SLitrani. Light yield measurements were performed in laboratory on LYSO and PbWO 4 crystals to have a comparison with the results obtained by mean of simulations. Good agreements are obtained for what regards surfaces treatments while more tuning was required to simulate the effect of surface imperfections and diffusion inside crystals. For the Collaboration purposes, Geant4 results more reliable and it allows to use GATE, an open source software specifically developed for the simulation of medical imaging scanners. Due to the peculiar structure of the PET prototype it was necessary to develop a code to simulate the electronic chain, responsible for transforming the gammas detected in usable data for image reconstruction. Different coincidences sorting algorithms were studied and methods to introduce instrumental uncertainties in data were developed and reported in this work. Simulations of EndoTOFPET scanner with different scintillator dimensions, modules geometries and plate configurations were performed. Sensibility and spatial resolution were used as elements of comparison and results collected by simulations are reported and analysed in this work. Time of flight was tested applying different time resolutions while system response to DOI analysis was studied too. Thanks to these first simulations, valuable information for the developing of this prototype were collected.

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Bevilacqua, Maurizio. « Novel models and methods for structured light 3D Scanners ». Doctoral thesis, Universita degli studi di Salerno, 2012. http://hdl.handle.net/10556/289.

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2010 - 2011
The work made during the PhD course in Information Engineering, was focused on the possibility to find out novel techniques for the quick calibration of a cheap 3D Scanner. It is based on a simple camera and a commercial projector, in order to develop low-cost devices with high reliability capable of acquiring large areas quickly. Many systems based on this configuration exist, those devices have benefits and disadvantages. They can acquire objects with large surface in a few seconds and with an adequate accuracy. On the other hand, they need a lengthy calibration and they are very sensitive to the noise due to the flicker of the light source. Considering these problems, I tried to find new robust calibration techniques in order to reduce the sensitivity to noise, and, in this way, to have high-performance low-cost 3D scanners with short-time calibration and reconfiguration. There are many calibration techniques available for these systems. First, it is necessary to calibrate the camera and then the overall system for projecting analog encoded patterns, typically sinusoidal or digital, such as Gray codes. These techniques are very time-consuming because they require a prior camera calibration phase separate from the calibration of the whole system and also disturbing factors are introduced by the ambient light noise. Indeed, a lot of projection patterns, used to map the calibration volume, are required to be projected. In order to achieve our goal, different types of structured light scanner have been studied and implemented, according to the schemes proposed in literature. For example, there exist scanners based on sinusoidal patterns and others based on digital patterns, which also allowed the implementation in real time mode. On these systems classical techniques of calibration were implemented and performance were evaluated ad a compromise between time and accuracy of the system. Classical calibration involves the acquisition of phase maps in the volume calibration following a pre-calibration of the camera. At the beginning, an algorithm that allows calibration through the acquisition of only two views has been implemented, including camera calibration, modeled by pin-hole model, in the calibration algorithm. To do this, we have assumed a geometric model for the projector which has been verified by the evaluation of experimental data. The projector is then modeled as a second camera, also using the pin-hole model, and we proceeded with the calibration of camera-projector pair as a pair of stereo cameras, using a DLT calibration. Thanks to the acquisition of two views of the target volume in the calibration, it is possible to extract the parameters of the two devices through which the projected pattern can be generated, and the acquisition by the camera can be done, eliminating the problem of noise due to ambient light. This system is a good compromise between the reduction in calibration time, which passed from half an hour to a couple of minutes, with a reduction in term of uncertainty in order of one percentage point of calibration volumes that was chosen of a depth of 10 centimeters… [edited by author]
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Forest, Collado Josep. « New Methods for Triangulation-based Shape Acquisition using Laser Scanners ». Doctoral thesis, Universitat de Girona, 2004. http://hdl.handle.net/10803/7730.

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Tradicionalment, la reproducció del mon real se'ns ha mostrat a traves d'imatges planes. Aquestes imatges se solien materialitzar mitjançant pintures sobre tela o be amb dibuixos. Avui, per sort, encara podem veure pintures fetes a ma, tot i que la majoria d'imatges s'adquireixen mitjançant càmeres, i es mostren directament a una audiència, com en el cinema, la televisió o exposicions de fotografies, o be son processades per un sistema computeritzat per tal d'obtenir un resultat en particular. Aquests processaments s'apliquen en camps com en el control de qualitat industrial o be en la recerca mes puntera en intel·ligència artificial. Aplicant algorismes de processament de nivell mitja es poden obtenir imatges 3D a partir d'imatges 2D, utilitzant tècniques ben conegudes anomenades Shape From X, on X es el mètode per obtenir la tercera dimensió, i varia en funció de la tècnica que s'utilitza a tal nalitat. Tot i que l'evolució cap a la càmera 3D va començar en els 90, cal que les tècniques per obtenir les formes tridimensionals siguin mes i mes acurades. Les aplicacions dels escàners 3D han augmentat considerablement en els darrers anys, especialment en camps com el lleure, diagnosi/cirurgia assistida, robòtica, etc. Una de les tècniques mes utilitzades per obtenir informació 3D d'una escena, es la triangulació, i mes concretament, la utilització d'escàners laser tridimensionals. Des de la seva aparició formal en publicacions científiques al 1971 [SS71], hi ha hagut contribucions per solucionar problemes inherents com ara la disminució d'oclusions, millora de la precisió, velocitat d'adquisició, descripció de la forma, etc. Tots i cadascun dels mètodes per obtenir punts 3D d'una escena te associat un procés de calibració, i aquest procés juga un paper decisiu en el rendiment d'un dispositiu d'adquisició tridimensional. La nalitat d'aquesta tesi es la d'abordar el problema de l'adquisició de forma 3D, des d'un punt de vista total, reportant un estat de l'art sobre escàners laser basats en triangulació, provant el funcionament i rendiment de diferents sistemes, i fent aportacions per millorar la precisió en la detecció del feix laser, especialment en condicions adverses, i solucionant el problema de la calibració a partir de mètodes geomètrics projectius.
Traditionally, the reproduction of the real world has been shown to us by means of at images. These images used to be materialised by means of paint on canvas, drawings or the like. Today, we still see hand made pictures, by fortune, although most of the images are acquired by cameras and they are either directly shown to an audience, like in the cinema, television or photographs, or they are processed by a computer system in order to obtain a particular result, like in industrial quality assurance or bleeding edge artificial intelligence research. Applying mid-level processing algorithms, 3D images can be obtained from 2D ones, using well known techniques called Shape From X, where X is the method for obtaining the 3rd dimension. While the evolution to the 3D camera begun in the 90s, the techniques for obtaining the most accurate 3D shape need to be continuously improving. The application of 3D scanners has spread signi cantly in the recent years, specially in elds like entertainment, assisted diagnosis/ surgery, robotics, etc. One of the most used techniques to obtain 3D information from a scene is triangulation, and more concretely, triangulationbased laser scanners. Since their formal appearance in scienti c publications, in 1971 [SS71], there have been contributions for solving inherent problems like occlusion avoidance, accuracy improvement, acquisition speed, shape description, etc. All of the methods for obtaining 3D points of a scene is accompained with a calibration procedure, and this procedure plays a decisive role in the performance of the acquisition device. The goal of this thesis is to provide a holistic approach to the problem of shape acquisition, giving a wide survey of triangulation laser scanners, testing the performance of di erent systems, and to give contributions for both improving acquisition accuracy under adverse conditions and solving the calibration problem. In addition, the calibration approach is based on previous works that used projective geometry to this end.

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Nagarajan, N. « Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners ». Thesis, Indian Institute of Science, 1994. http://hdl.handle.net/2005/155.

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Autonomous navigation is the determination of satellites position and velocity vectors onboard the satellite, using the measurements available onboard. The orbital information of a satellite needs to be obtained to support different house keeping operations such as routine tracking for health monitoring, payload data processing and annotation, orbit manoeuver planning, and prediction of intrusion in various sensors' field of view by celestial bodies like Sun, Moon etc. Determination of the satellites orbital parameters is done in a number of ways using a variety of measurements. These measurements may originate from ground based systems as range and range rate measurements, or from another satellite as in the case of GPS (Global Positioning System) and TDUSS (Tracking Data Relay Satellite Systems), or from the same satellite by using sensors like horizon sensor^ sun sensor, star tracker, landmark tracker etc. Depending upon the measurement errors, sampling rates, and adequacy of the estimation scheme, the navigation accuracy can be anywhere in the range of 10m - 10 kms in absolute location. A wide variety of tracking sensors have been proposed in the literature for autonomous navigation. They are broadly classified as (1) Satellite-satellite tracking, (2) Ground- satellite tracking, (3) fully autonomous tracking. Of the various navigation sensors, it may be cost effective to use existing onboard sensors which are well proven in space. Hence, in the current thesis, the Horizon scanner is employed as the primary navigation sensor-. It has been shown in the literature that by using horizon sensors and gyros, a high accuracy pointing of the order of .01 - .03 deg can be achieved in the case of low earth orbits. Motivated by such a fact, the current thesis deals with autonomous orbit determination using measurements from the horizon sensors with the assumption that the attitude is known to the above quoted accuracies. The horizon scanners are mounted on either side of the yaw axis in the pitch yaw plane at an angle of 70 deg with respect to the yaw axis. The Field Of View (FOV) moves about the scanner axis on a cone of 45 deg half cone angle. During each scan, the FOV generates two horizon points, one at the space-Earth entry and the other at the Earth-space exit. The horizon points, therefore, lie• on the edge of the Earth disc seen by the satellite. For a spherical earth, a minimum of three such horizon points are needed to estimate the angular radius and the center of the circular horizon disc. Since a total of four horizon points are available from a pair of scanners, they can be used to extract the satellite-earth distance and direction.These horizon points are corrupted by noise due to uncertainties in the Earth's radiation pattern, detector mechanism, the truncation and roundoff errors due to digitisation of the measurements. Owing to the finite spin rate of the scanning mechanism, the measurements are available at discrete time intervals. Thus a filtering algorithm with appropriate state dynamics becomes essential to handle the •noise in the measurements, to obtain the best estimate and to propagate the state between the measurements. The orbit of a low earth satellite can be represented by either a state vector (position and velocity vectors in inertial frame) or Keplerian elements. The choice depends upon the available processors, functions and the end use of the estimated orbit information. It is shown in the thesis that position and velocity vectors in inertial frame or the position vector in local reference frame, do result in a simplified, state representation. By using the f and g series method for inertial position and velocity, the state propagation is achieved in linear form. i.e. Xk+1 = AXK where X is the state (position, velocity) and A the state transition matrix derived from 'f' and 'g' series. The configuration of a 3 axis stabilised spacecraft with two horizon scanners is used to simulate the measurements. As a step towards establishing the feasibility of extracting the orbital parameters, the governing equations are formulated to compute the satellite-earth vector from the four horizon points generated by a pair of Horizon Scanners in the presence of measurement noise. Using these derived satellite-earth vectors as measurements, Kalman filter equations are developed, where both the state and measurements equations are linear. Based on simulations, it is shown that a position accuracy of about 2 kms can be achieved. Additionally, the effect of sudden disturbances like substantial slewing of the solar panels prior and after the payload operations are also analysed. It is shown that a relatively simple Low Pass Filter (LPF) in the measurements loop with a cut-off frequency of 10 Wo (Wo = orbital frequency) effectively suppresses the high frequency effects from sudden disturbances which otherwise camouflage the navigational information content of the signal. Then Kalman filter can continue to estimate the orbit with the same kind of accuracy as before without recourse to re-tuning of covariance matrices. Having established the feasibility of extracting the orbit information, the next step is to treat the measurements in its original form, namely, the non-linear form. The entry or exit timing pulses generated by the scanner when multiplied by the scan rate yield entry or exit azimuth angles in the scanner frame of reference, which in turn represents an effective measurement variable. These azimuth angles are obtained as inverse trigonometric functions of the satellite-earth vector. Thus the horizon scanner measurements are non-linear functions of the orbital state. The analytical equations for the horizon points as seen in the body frame are derived, first for a spherical earth case. To account for the oblate shape of the earth, a simple one step correction algorithm is developed to calculate the horizon points. The horizon points calculated from this simple algorithm matches well with the ones from accurate model within a bound of 5%. Since the horizon points (measurements) are non-linear functions of the state, an Extended Kalman Filter (EKF) is employed for state estimation. Through various simulation runs, it is observed that the along track state has got poor observability when the four horizon points are treated as measurements in their original form, as against the derived satellite-earth vector in the earlier strategy. This is also substantiated by means of condition number of the observability matrix. In order to examine this problem in detail, the observability of the three modes such as along-track, radial, and cross-track components (i.e. the local orbit frame of reference) are analysed. This difficulty in observability is obviated when an additional sensor is used in the roll-yaw plane. Subsequently the simulation studies are carried out with two scanners in pitch-yaw plane and one scanner in the roll-yaw plane (ie. a total of 6 horizon points at each time). Based on the simulations, it is shown that the achievable accuracy in absolute position is about 2 kms.- Since the scanner in the roll-yaw plane is susceptible to dazzling by Sun, the effect of data breaks due to sensor inhibition is also analysed. It is further established that such data breaks do not improve the accuracy of the estimates of the along-track component during the transient phase. However, filter does not diverge during this period. Following the analysis of the' filter performance, influence of Earth's oblateness on the measurement model studied. It is observed that the error in horizon points, due to spherical Earth approximation behave like a sinusoid of twice the orbital frequency alongwith a bias of about 0.21° in the case of a 900 kms sun synchronous orbit. The error in the 6 horizon points is shown to give rise to 6 sinusoids. Since the measurement model for a spherical earth is the simplest one, the feasibility of estimating these sinusoids along with the orbital state forms the next part of the thesis. Each sinusoid along with the bias is represented as a 3 state recursive equation in the following form where i refers to the ith sinusoid and T the sampling interval. The augmented or composite state variable X consists of bias, Sine and Cosine components of the sinusoids. The 6 sinusoids together with the three dimensional orbital position vector in local coordinate frame then lead to a 21 state augmented Kalman Filter. With the 21 state filter, observability problems are experienced. Hence the magnetic field strength, which is a function of radial distance as measured by an onboard magnetometer is proposed as additional measurement. Subsequently, on using 6 horizon point measurements and the radial distance measurements obtained from a magnetometer and taking advantage of relationships between sinusoids, it is shown that a ten state filter (ie. 3 local orbital states, one bias and 3 zero mean sinusoids) can effectively function as an onboard orbit filter. The filter performance is investigated for circular as well as low eccentricity orbits. The 10-state filter is shown to exhibit a lag while following the radial component in case of low eccentricity orbits. This deficiency is overcome by introducing two more states, namely the radial velocity and acceleration thus resulting in a 12-state filter. Simulation studies reveal that the 12-state filter performance is very good for low eccentricity orbits. The lag observed in 10-state filter is totally removed. Besides, the 12-state filter is able to follow the changes in orbit due to orbital manoeuvers which are part of orbit acquisition plans for any mission.

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Norström, Alexander. « Measuring Accurancy of Vulnerability Scanners : An Evaluation with SQL Injections ». Thesis, Linköpings universitet, Informationskodning, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-106628.

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Web application vulnerabilities of critical are commonly found in web applications. The arguably most problematic class of web application vulnerabilities is SQL injections. SQL injection vulnerabilities can be used to execute commands on the database coupled to the web application, e.g., to extract the web application’s user and passwords data. Black box testing tools are often used (both by system owners and their adversaries) to discover vul- nerabilities in a running web application. Hence, how well they perform at discovering SQL injection vulnerabilities is of importance. This thesis describes an experiment assessing de- tection capability for different SQL injection vulnerabilities under different conditions. In the experiment the following is varied: SQL injection vulnerability (17 instances allowing tautologies, piggy-backed queries, and logically incorrect queries), scanners (four products), exploitability (three levels), input vector (POST/GET), and time investment (three levels). The number of vulnerabilities detected is largely determined by the choice of scanner (30% to 77%) and the input vector (71% or 38%). The interaction between the scanner and input vector is substantial since two scanners cannot handle the POST-vector at all. Substantial differences are also found between how well different SQL injection vulnerabilities are de- tected and the more exploitable variants are detected more often, as expected. The impact of time spent with the scan interacts with the scanner - some scanners required considerable time to configure and other did not – and as a consequence the relationship between time investments to detection capabilities is non-trivial.

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Medić, Tomislav [Verfasser]. « Efficient calibration strategies for panoramic terrestrial laser scanners / Tomislav Medić ». Bonn : Universitäts- und Landesbibliothek Bonn, 2021. http://d-nb.info/1227990456/34.

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Borges, Paulo Augusto Ferreira. « Lasers scanners terrestres : desenvolvimento de metodologias para análise da acurácia ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3138/tde-17072017-152847/.

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A calibração de instrumento é reconhecida como um importante processo para a garantia de qualidade de dados obtidos a partir de um laser scanner terrestre (TLS). Um aspecto importante na garantia da qualidade de nuvem de pontos tridimensionais capturadas com instrumentos TLS é a calibração geométrica. Erros sistemáticos inerentes aos instrumentos, se não corrigidos, podem degradar a acurácia da nuvem de pontos obtida pelo scanner. A modelagem destes erros sistemáticos e o uso de metodologias de calibração para estimativa dos coeficientes do modelo permitem quantificar e avaliar a qualidade e a acurácia dos sistemas lasers scanners terrestres. Identificar os diferentes erros inerentes ao equipamento ou ao processo de medição é um fator de grande importância para certificá-los, comprovando sua conformidade com a precisão nominal definida pelos fabricantes. Esta dissertação apresenta propostas de diferentes metodologias para aferição e calibração de laser scanners terrestres. A primeira metodologia refere-se à auto-calibração de TLS que permite obter os parâmetros de calibração referentes aos erros sistemáticos de distância (??), colimação (?C), direção horizontal (??) e o erro de índice vertical (??). Dois equipamentos foram submetidos à auto-calibração, um equipamento novo, recém-fabricado, modelo Faro Focus 3D X330, que foi utilizado como referência, e um equipamento antigo, modelo Faro Photon 80, que devido ao tempo de constante uso foi submetido à aferição. Os resultados comprovaram a eficiência da metodologia de auto-calibração na determinação dos parâmetros de correção sistemática adicional, indicando que o scanner novo apresentou resultados dentro das especificações e o modelo antigo, resultados acima dos valores de precisão definidos pelo fabricante. Visando facilitar os procedimentos de campo e escritório para fins de calibração de TLS foram propostas duas metodologias com a utilização de peças fabricadas para uso no presente trabalho, visando a obtenção da acurácia tridimensional de um TLS. A primeira consiste na utilização de uma placa de aço com nove furos sobre os quais são alojadas nove esferas de poliacetal. A segunda consiste na utilização de um sistema tridimensional de planos perpendiculares, através do qual pode-se obter a acurácia 3D do TLS. Os resultados obtidos comprovam a eficiência das duas metodologias propostas, aplicadas em procedimentos de calibração em laboratório utilizando varreduras em equipamentos de curto alcance. Por fim foram realizados testes para determinação dos parâmetros de calibração relativos ao erro de zero ou constante aditiva, o erro de escala e o erro cíclico em linhas bases de calibração EDM, utilizando-se a rede de pilares da USP. Os resultados comprovam a necessidade de contar com distâncias entre pilares menores para utilização em TLS de curto alcance, porém, para laser scanners com maior autonomia de distância se mostrou um método eficiente.
Instrument calibration is recognized as an important process for quality assurance of data obtained from a terrestrial laser scanner (TLS). An important aspect in ensuring the quality of three-dimensional point cloud captured with TLS instruments is geometric calibration. Systematic errors inherent in the instruments, if not corrected, can degrade the accuracy of the cloud of points obtained by the scanner. The modeling of these systematic errors and the use of calibration methodologies to estimate the coefficients of the model allow quantifying and evaluating the quality and accuracy of the laser systems. Identifying the different errors inherent in the equipment or the measurement process is a factor of great importance to certify them, proving their conformity with the nominal precision defined by the manufacturers. This dissertation presents proposals of different methodologies for calibration of terrestrial laser scanners. The first methodology refers to TLS self-calibration, which allows to obtain the calibration parameters for systematic errors of distance (??), collimation (?C), horizontal direction (??) and vertical index error (??). Two devices were submitted to self-calibration, a new, newly manufactured Faro Focus 3D X330 model, which was used as reference, and an old equipment, Faro Photon 80 model, which due to the time of constant use was subjected to the calibration . The results proved the efficiency of the self-calibration methodology in determining the additional systematic correction parameters, indicating that the new scanner presented results within the specifications and the old model, values above the precision values defined by the manufacturer. In order to facilitate the field and office procedures for TLS calibration purposes, two methodologies were proposed with the use of prefabricated parts to obtain the three-dimensional accuracy of a TLS. The first proposes the use of a steel plate with nine holes on which are housed nine spheres of polyacetal. The second refers to the use of a three-dimensional system of perpendicular planes, where from the point cloud of the different planes the 3D accuracy of the TLS can be obtained. The results obtained prove the efficiency of the two proposed methodologies, applied in laboratory calibration procedures using short-range scans. Finally, tests were carried out to determine the calibration parameters related to the error of zero or additive constant, the scale error and the cyclic error in EDM calibration baselines, using the USP\'s network of columns. The results confirm the need for adequacy of the distance between columns for use in short-range TLS, but for laser scanners with greater distance autonomy an efficient method was shown.

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Rombourg, Romain. « Analyse, modélisation et détection de bruits pour scanners laser terrestres ». Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAM064.

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Dans cette thèse, nous nous sommes concentrés sur plusieurs sujets liés à la détection du bruit dans les nuages de points générés par les scanners laser terrestres (TLS). Premièrement, les méthodes de projection pour calculer une image à partir d'un balayage TLS. Deuxièmement, la détection du bruit du ciel, c'est-à-dire le bruit produit lorsqu'une mesure d'un TLS à onde continue modulée en amplitude n'est effectuée que sur du rayonnement ambiant. Et enfin, la détection du bruit de points mixtes, c'est-à-dire les points acquis lorsque le TLS reçoit des signaux de retour de plusieurs surfaces différentes. Pour relever ces défis, nous avons d'abord analysé l'échantillonnage de l'espace du TLS et déduit des propriétés sur la densité locale de points en fonction de l'altitude, ce qui nous a permis de montrer les limites des techniques classiques de détection. Nous avons ensuite défini un cadre théorique pour analyser les méthodes de projection, fondements des méthodes de détection 2D. Ce cadre nous a permis de mettre en évidence deux propriétés fondamentales devant être satisfaites par une projection. En se basant sur ces propriétés, nous avons conçu un algorithme de projection les satisfaisant au mieux. Nous avons ensuite défini une quantification de la qualité d'une projection et comparé notre algorithme avec l'algorithme classique et montré que la méthode classique n'est pas adaptée. La projection proposée a quant à elle donné de très bons résultats. Comme le bruit du ciel n'a jamais été étudié dans de précédents travaux, nous l'avons formellement analysé pour construire des bases théoriques pour la détection du ciel. L'analyse nous a permis de montrer théoriquement et expérimentalement que la distribution de distance du bruit de ciel est indépendante des propriétés sous-jacentes du rayonnement ambiant. à partir de notre projection et des propriétés découvertes, nous avons conçu un détecteur de ciel et un détecteur de points mixtes. Les détecteurs ont été testés via une validation approfondie en conditions contrôlées. Les résultats ont montré que nos détecteurs combinés à notre projection sont capables de détecter correctement presque tous le bruit présenté avec peu de mauvaises détections pour le détecteur de ciel et une quantité raisonnable pour le détecteur de point mixte
In this thesis, we focused on several topics related to noise detection in point cloud generated by Terrestrial Laser Scanners (TLS). First, the projection methods to compute an image from a TLS scan. Second, the detection of sky noise, i.e. noise produced when a Amplitude Modulated Continuous Wave TLS measures range only from background radiation. And finally, the detection of mixed point noise, i.e. points acquired when the TLS was receiving return signals from several different surfaces. To tackle these challenges, we first analysed how the TLS samples space and deduced properties on how the local point cloud density evolves with respect to the elevation, this allowed us to show the limits of usual noise detection techniques and oriented our focus on 2D non density based detection techniques. We then defined a theoretical framework to analyse projection methods, unavoidable foundations for 2D detection methods. This framework allowed us to bring to light two fundamental properties that should be satisfied by a projection. Following these properties, we designed a projection algorithm that satisfied them as much as possible. We then defined a way to quantify projection quality and compared our proposed algorithm with the widely used classic algorithm and showed that the classic projection method is not adapted. Our proposed projection however showed very good results. Since the sky noise was never studied in previous works, we formally analysed it to build some theoretical foundations for sky detection. The analysis allowed us to show theoretically and experimentally that the range distribution of sky noise is independent of the underlying properties of the background radiation signal. From our projection and the discovered properties, we designed a sky detector and a mixed point detector. The detectors were tested via an extensive validation in controlled conditions. The results showed that our proposed detectors combined with the proposed projection are able to correctly detect almost all presented noise with few bad detection for the sky detectors and reasonable amount for the mixed point detector

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Wu, Lei. « Low-voltage, large-range MEMS optical scanners and their applications ». [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024705.

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Cure, Laura Leonard. « Usefulness of Medication Scanners in Clinical Practice : A Systematic Review ». ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/6004.

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Thousands of people die each year due to preventable medication errors. Barcode medication administration (BCMA) systems can reduce medication errors at the point of care, thus increasing patient safety. The purpose of the project was to gather evidence regarding BCMA usefulness in reducing medication errors. Kurt Lewin's 3-step change theory was used to guide this project. The nature of this project was a systematic review of the literature pertaining to the effectiveness of using BCMA systems to reduce medication errors in at the point of care in the hospital setting. The Johns Hopkins nursing evidence-based practice model and tool kit was used to evaluate each article. The review comprised one systematic review, one integrative review, and 6 before-and-after observational studies. The results of each study indicated that the use of a BCMA system could reduce medication errors but not completely eliminate them. The findings of this project contribute evidence that BCMA systems can assist the clinician in safely administering medication. Dissemination of the evidence will contribute to a positive change by promoting greater understanding of the effectiveness of using BCMA systems in all areas that administer medication.

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Cain, James H. « Image motion compensation for an electronic imaging system / ». Online version of thesis, 1986. http://hdl.handle.net/1850/8731.

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Basso, Tânia 1981. « Uma abordagem para avaliação da eficácia de scanners de vulnerabilidades em aplicações web ». [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261545.

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Orientadores: Mário Jino, Regina Lúcia de Oliveira Moraes
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: Grande parte das aplicações Web é desenvolvida atualmente sob severas restrições de tempo e custo. A complexidade dos produtos de software é cada vez maior resultando em vulnerabilidades de segurança produzidas por má codificação. Ferramentas chamadas scanners de vulnerabilidade são utilizadas para auxiliar a detecção automática de vulnerabilidades de segurança em aplicações Web; portanto, poder confiar nos resultados da aplicação dessas ferramentas é essencial. Este trabalho propõe uma abordagem para avaliar a eficácia desses scanners. A abordagem proposta está baseada em técnicas de injeção de falhas e modelos de árvores de ataque; os resultados da aplicação de três scanners são avaliados na presença de falhas realistas de software responsáveis por vulnerabilidades de segurança em aplicações Web. As árvores de ataque representam os passos para se realizar um ataque, permitindo verificar se vulnerabilidades detectadas pelo scanner existem de fato na aplicação sob teste. A abordagem também pode ser utilizada para realizar testes de segurança, pois permite a detecção de vulnerabilidades pela execução de cenários de ataque
Abstract: Nowadays, most web applications are developed under strict time and cost constraints. The complexity of software products is increasingly bigger leading to security vulnerabilities due to bad coding. Tools called vulnerability scanners are being applied to automatically detect security vulnerabilities in web applications; thus, trustworthiness of the results of application of these tools is essential. The present work proposes an approach to assess the efficacy of vulnerability scanner tools. The proposed approach is based on fault injection techniques and attack tree models; the results of the application of three scanners are assessed in the presence of realistic software faults responsible for security vulnerabilities in web applications. Attack trees represent the steps of performing an attack, allowing verifying whether security vulnerabilities detected by the scanner tool do exist in the application under test. The approach can also be used to perform security tests, as it permits the detection of vulnerabilities through the execution of attack scenarios
Mestrado
Engenharia de Computação
Mestre em Engenharia Elétrica

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Reshetyuk, Yuriy. « Investigation and calibration of pulsed time-of-flight terrestrial laser scanners ». Licentiate thesis, Stockholm : Division of Geodesy, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4126.

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Schneider, Jale [Verfasser]. « Entwicklung eines ultraschnellen elektro-optischen Scanners für STED-Nanoskopie / Jale Schneider ». Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/103851391X/34.

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Grafulla-Gonzalez, Beatriz. « Physical optics modelling for the optimization of millimetre-wave personnel scanners ». Thesis, Heriot-Watt University, 2007. http://hdl.handle.net/10399/2098.

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Active millimetre-wave imaging systems can be employed in security applications to recognise and identify concealed weapons among clothing. Nevertheless, generated images have some limitations in various aspects. These are primarily related with the high amount of noise present in the system, the poor spatial resolution and the insufficient thermal contrast produced by certain scene components. The main goal of this thesis has been to develop a physical optics modelling of the millimetre-wave image formation (theoretical and computer-based) for the optimization of current millimetre-wave systems. To this etfect, we have implemented a comprehensive millimetre-wave image simulator, which was developed to fulfil the existing gap in the millimetre-wave modelling at the time this system was needed. The major advantage of this innovative system is that it offers low-cost and rapid exploration of the effects of various key parameters of the image formation process. Thus, the optimization is carried out by setting up different im- ager configurations with the simulator and by generating the cor- responding synthetic images for different scenes. The enhanced understanding that these synthetic images provide has enabled the improvement of real millimetre-wave images in terms of thermal contrast or noise. This thesis has contributed in three different areas. First, it provides a theoretical model which includes all the stages of millimetre-wave image formation. Second, it describes the design and implementation of a novel millimetre-wave image simulator, which is capable of generating realistic and mathematically validated images. And third, it reports the exploration of different optimizations that may be carried out within current millimetrewave systems regarding both physical and post-processing aspects.

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Weirich, Christoph Peter [Verfasser]. « Quantitative PET imaging with hybrid MR-PET scanners / Christoph Peter Weirich ». Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1052299563/34.

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Weirich, Christoph [Verfasser]. « Quantitative PET imaging with hybrid MR-PET scanners / Christoph Peter Weirich ». Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://nbn-resolving.de/urn:nbn:de:hbz:82-opus-50383.

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Milburn, David L. « Using measured photography to obtain optimal results from CCD color scanners / ». Online version of thesis, 1993. http://hdl.handle.net/1850/11095.

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Góis, Renata de Freitas. « Investigação do uso de imagens mamográficas adquiridas em diferentes digitalizadores no desempenho do processamento de imagens para detecção de microcalcificações ». Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-07022007-114730/.

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O presente projeto de pesquisa trata de uma comparação no processamento de imagens mamográficas adquiridas no scanner a laser (Lumiscan50) e no scanner óptico convencional com adaptador para digitalização de filme (Umax mod. PowerLook 1120). Por meio de uma análise estatística, verificou-se que o scanner óptico produz um aumento acentuado na intensidade (nível de cinza) na imagem digitalizada em relação ao mamograma original. Em função dessas respostas, foi desenvolvido um procedimento para compensar o deslocamento da curva de cada digitalizador em relação à curva característica do filme. Em seguida, imagens selecionadas de exposições de phantom e de mamografias reais foram digitalizadas em ambos os scanners e processadas por uma técnica de segmentação para detecção de microcalcificações, desenvolvida previamente no nosso grupo de pesquisas, a fim de estabelecer uma comparação da sensibilidade de detecção do esquema para imagens digitalizadas pelos dois tipos de equipamentos. Baseada nestas comparações, a análise do comportamento de um esquema CAD em mamografia, considerando a utilização de imagens digitalizadas em ambos os tipos de scanners, mostrou equivalência na sensibilidade e na especificidade, mas somente quando foi aplicada a técnica de transformação com base na análise das respectivas curvas características. Embora a performance do esquema tenha sido cerca de 10% mais eficiente com as imagens digitalizadas pelo sistema laser, a redução no nível de intensidade das imagens do digitalizador óptico que, na prática, significou aproximar a sua curva característica em relação a curva característica do laser proporcionou resultados equivalentes da segmentação. Ao considerar também que a tecnologia a laser é bastante cara e a tecnologia CCD tem um custo absurdamente menor, verifica-se a possibilidade da utilização dessa última sem prejudicar a eficácia no processamento, desde que aplicado o software de correção apropriado baseado na análise das curvas características.
This work is intended in comparing the results from a mammographic images processing scheme considering images sets digitized by a laser and by an optical scanners (Lumiscan50 and Umax Powerlook 1120 units, respectively). By means of a statistical analysis, we could verify that the optical scanner yields a remarkable increase in the digitized image intensity (gray scale) relative to the original mammogram. A procedure was developed to compensate the shift each digitizers characteristic curves relative to the film one, as a function of such responses. Then, selected images from phantom exposures as well as from actual mammographic exams were digitized by both scanners and processed by a previously developed segmentation technique for detection of clustered microcalcifications in order to establish the comparisons. The results have shown that, considering the use of images digitized by both types of scanners, there was an equivalence between the two images sets as for sensibility as well as for specificity, but only when applied the transformation technique based on the analysis of the digitizers respective characteristic curves. Although the scheme performance was about 10% more efficient with the images set from the laser scanner, when an intensity level decrease procedure was introduced to the images from the optical digitizer which means to approach its characteristic curve to the laser digitizer one the segmentation results were equivalent. Therefore, taking into account that the laser technology is very expensive while the CCD one is notably smaller, the results show that extending the CCD technology use to CAD schemes in mammography is a real possibility, without prejudice the processing efficacy. But this is possible only when applied the appropriate correction by means of the characteristic curves study.

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Souček, Ondřej. « Optické scannery - měření kinematických bodů zavěšení ». Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229118.

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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.

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Schilling, Bradley Wade. « Advances in real-time optical scanning holography ». Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09122009-040312/.

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Oliveira, Luiz Claudio Marangoni de 1975. « Contribuições para melhoria do desempenho e viabilidade de fabricação de scanners indutivos ». [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263395.

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Orientador: Luiz Otavio Saraiva Ferreira
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
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Resumo: Scanners são dispositivos que defletem um feixe luminoso e transfonnam um feixe puntual em uma linha de varredura, com amplitude e freqüência controladas. Diversos equipamentos utilizam este padrão luminoso para codificar ou decodificar infonnações, exemplos mais comuns são os leitores de código de barras de bancada, utilizados em supennercados, e as impressoras laser. V ários fenômenos podem ser empregados para defletir um feixe luminoso. Neste trabalho, os scanners utilizam o princípio da reflexão da luz por um espelho em movimento hannônico e ressonante sob ação de forças de origem eletromagnética. Tais forças são geradas pela interação de correntes induzi das na annadura, com o campo magnético produzido por ímãs pennanentes. A principal vantagem deste tipo de scanner é a ausência de conexões elétricas entre as partes móveis e fixas do dispositivo, o que simplifica o processo de fabricação e o toma mais robusto e menos suceptível a falhas. Parte dos scanners similares existentes atualmente são dispositivos eletro-mecânicos complexos, fabricados em série. Trabalhos anteriores demonstraram a viabilidade da geometria planar e da utilização de processos de fabricação em lotes, derivados da microeletrônica, neste tipo de scanner. Os protótipos fabricados, embora funcionais, apresentaram consumo de potência acima da média para este tipo de dispositivo, o que demonstrava a necessidade de melhorias em seu projeto. O processo de fabricação, embora confiável, foi desenvolvido com materiais e métodos baseados no Silício e originários da microeletrônica, o que dificultava sua implantação em indústrias em território nacional. Neste trabalho, foram pr9postos aprimoramentos à tecnologia dos scanners ressonantes planares atuados por indução para tomar seu desempenho compatível com o d~ dispositivos similares, e também para viabilizar sua fabricação utilizando materiais e métodos disponíveis no país. Uma metodologia de projeto, em conjunto com uma série de contribuições ao modelo, foi proposta e avaliada. Para viabilizar a fabricação propôs-se a utilização do Bronze-fosforoso, como material estrutural, e a utilização de foto-fabricação, como processo de fabricação. As contribuições propostas neste trabalho possibilitaram a redução do consumo de potência de 2, 2 W para cerca de 5 m W por grau óptico, e o aumento da freqüência de operação do circuito de cerca de 1 kHz para 4 kHz, com um ângulo de deflexão óptico típico de 20° pico-a-pico, parâmetros compatíveis com os de dispositivos similares, mas mecanicamente mais complexos e fabricados por processo serial
Abstract: Scanners are devices that deftects a light beam and converts a spot light in a well controlled amplitude and frequency scan line. Several applications uses the generated pattem to code or decode data, common examples ar,e barcode readers, and laser printers. A light beam can be deftected by different means. In this work, the scanner deftects the light by reftection in a moving mirror, in a resonant and harmonic movement, subjected to forces of electromagnetic nature. Such forces are generated by the interaction between an induced current in the armature, and a magnetic field, generated by permanent magnets. The main advantage of this kind of scanner is the absence of electrical connections between the mobile, and fixed parts of the device, that simplifies the fabrication process, and make its more reliable and less fault susceptible. Part of the similar devices available today are complex eIectro-mechanical devices, manufactured by serial processo Earlier works established that the planar geometry, and the use of batch fabrication process, derived from microelectronics, are feasible with this kind of device. A1though functional, the earlier prototypes presented a high power consumption, that shown the demand for an improved designo The Silicon-based fabrication process adopted makes the use of materiaIs and methods that are not readily accessible to the Brazilian industry. In this work improvements were proposed to the induction actuated planar resonant scanners technology. The goal was to make its performance compatible with the performance of similar devices, and to enable its fabrication using materiaIs and methods available to the Brazilian industry. A design m~thodology, and a set of model contributions were proposed and validated. The use of Phosphor-bronze, as structural material, and the photqfabrication process, as the machining method, were proposed as an option to the Silicon-based fabrication method. The contributions ofthis work had enabled the reduction ofthe power consumptlon from 2,2 W to about 5 m W per optical degree, and an increase in the working frequency from 1 kHz to 4kHz, with a optical deftection angle of about 20° peak-to-peak. Such parameters are fully compatible with similar devices, mechanically more complexes and manufactured by serial processes
Doutorado
Mecanica dos Sólidos e Projeto Mecanico
Doutor em Engenharia Mecânica

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Zúñiga, Laura Daniela Ordierez. « Método de verificação do desempenho do scanners laser usando um artefato tridimensional ». reponame:Repositório Institucional da UnB, 2014. http://repositorio.unb.br/handle/10482/17016.

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Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Pós-Graduação em Sistemas Mecatrônicos, 2013.
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Instrumentos como scanner laser 3D são atualmente utilizados em diversas aplicações de engenharia reversa, uma vez que admitem a aquisição de informações da geometria da peça de objetos num tempo reduzido de medição resultando na redução de custos. Comparando com os instrumentos de medição com contato, como máquinas de medição por coordenadas (MMC). A verificação de desempenho de scanners a laser está em estudo e, atualmente, não há padrões nem normas universais para resolver este problema. Esta dissertação propõe um método para verificar o desempenho do scanners laser 3D do fabricante NextEngine. A abordagem experimental foi implementada usando um scanner a laser 3D fabricado pela NextEngine. Um padrão tridimensional foi projetado e fabricado em alumínio, com características geométricas específicas, como círculos, cilindros, aviões e esferas. As características geométricas como raios, ângulos e alturas foram determinadas através da medição em uma MMC cantilever com sonda de gatilhamento (valores convencionais). Os valores destas mesmas características foram medidas no scanner laser e comparadas com os valores convencionais, sendo que o desempenho do instrumento foi avaliado pela repetitividade e pela amplitude dos erros encontrados. O método foi adequado para avaliar o desempenho do instrumento verificado através de estimativas de exatidão e repetitividade. _______________________________________________________________________________________ ABSTRACT
Tridimensional laser scanner is nowadays used in several applications of reverse engineering since it admits acquisition of geometric information at reduced measurement time and cost. Comparing with instruments as Coordinate Measuring Machines (CMM).The performance verification of laser scanners is under study and currently there is no standard to address this issue. This work proposes a method to verify the performance of 3D laser scanners manufactured by Next Engine. The experimental approach was implemented using 3D laser scanner manufactured by NextEngine. A tridimensional gauge was designed and manufactured in aluminum with specific geometrical features like circles, cylinders, planes and spheres. The measured geometric characteristics were radius, angles and heights. That was determined by MMC (conventional value). These dimensions were determined by a laser scanner and compared with the calibrated values. The method was suitable to evaluate the instrument performance as estimates of the accuracy and the repeatability were obtained.

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Gupta, Shruti. « Performance Analysis of Quantitative Bone Measurement with Spiral, Multi-Detector CT Scanners ». Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1229708472.

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Jouini, Mohamed Soufiane. « Caractérisation des réservoirs basée sur des textures des images scanners de carottes ». Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13769/document.

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Les carottes, extraites lors des forages de puits de pétrole, font partie des éléments les plus importants dans la chaîne de caractérisation de réservoir. L’acquisition de celles-ci à travers un scanner médical permet d’étudier de façon plus fine les variations des types de dépôts. Le but de cette thèse est d’établir les liens entre les imageries scanners 3D de carottes, et les différentes propriétés pétrophysiques et géologiques. Pour cela la phase de modélisation des images, et plus particulièrement des textures, est très importante et doit fournir des descripteurs extraits qui présentent un assez haut degrés de confiance. Une des solutions envisagée pour la recherche de descripteurs a été l’étude des méthodes paramétriques permettant de valider l’analyse faite sur les textures par un processus de synthèse. Bien que ceci ne représente pas une preuve pour un lien bijectif entre textures et paramètres, cela garantit cependant au moins une confiance en ces éléments. Dans cette thèse nous présentons des méthodes et algorithmes développés pour atteindre les objectifs suivants : 1. Mettre en évidence les zones d’homogénéités sur les zones carottées. Cela se fait de façon automatique à travers de la classification et de l’apprentissage basés sur les paramètres texturaux extraits. 2. Établir les liens existants entre images scanners et les propriétés pétrophysiques de la roche. Ceci se fait par prédiction de propriétés pétrophysiques basées sur l’apprentissage des textures et des calibrations grâce aux données réelles.
Cores extracted, during wells drilling, are essential data for reservoirs characterization. A medical scanner is used for their acquisition. This feature provide high resolution images improving the capacity of interpretation. The main goal of the thesis is to establish links between these images and petrophysical data. Then parametric texture modelling can be used to achieve this goal and should provide reliable set of descriptors. A possible solution is to focus on parametric methods allowing synthesis. Even though, this method is not a proven mathematically, it provides high confidence on set of descriptors and allows interpretation into synthetic textures. In this thesis methods and algorithms were developed to achieve the following goals : 1. Segment main representative texture zones on cores. This is achieved automatically through learning and classifying textures based on parametric model. 2. Find links between scanner images and petrophysical parameters. This is achieved though calibrating and predicting petrophysical data with images (Supervised Learning Process)

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Heinström, Jannica. « Fast surfers, broad scanners and deep divers : personality and information-seeking behaviour / ». Åbo : Åbo Akademi university press, 2002. http://catalogue.bnf.fr/ark:/12148/cb40050439n.

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Hyllienmark, Erik. « Evaluation of two vulnerability scanners accuracy and consistency in a cyber range ». Thesis, Linköpings universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-160092.

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One challenge when conducting exercises in a cyber range is to know what applications and vulnerabilities are present on deployed computers. In this paper, the reliability of application-and vulnerability reporting by two vulnerability scanners, OpenVas and Nexpose, have been evaluated based on their accuracy and consistency. Followed by an experiment, the configurations on two virtual computers were varied in order to identify where each scanner gathers information. Accuracy was evaluated with the f1-score, which combines the precision and recall metric into a single number. Precision and recall values were calculated by comparing installed ap-plications and vulnerabilities on virtual computers with the scanning reports. Consistency was evaluated by quantifying how similar the reporting of applications and vulnerabilities between multiple vulnerability scans were into a number between 0 and 1. The vulnerabilities reported by both scanners were also combined with their union and intersection to increase the accuracy. The evaluation reveal that neither Nexpose or OpenVas accurately and consistently report installed applications and vulnerabilities. Nexpose reported vulnerabilities better than OpenVas with an accuracy of 0.78. Nexpose also reported applications more accurately with an accuracy of 0.96. None of the scanners reported both applications and vulnerabilities consistently over three vulnerability scans. By taking the union of the reported vulnerabilities by both scanners, the accuracy increased by 8 percent compared with the accuracy of Nexpose alone. However, our conclusion is that the scanners’ reporting does not perform well enough to be used for a reliable inventory of applications and vulnerabilities in a cyber range.

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Al, Mohammad Badera. « Quantitative MRI quality control using the ACR phantom ». Thesis, Boston University, 2012. https://hdl.handle.net/2144/32037.

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Thesis (M.A.)--Boston University
PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
Recently, many studies have used T1 and T2 quantitative MRI in examining the brain and other body structures, to evaluate and follow up diseases, or simply for better understanding of the human body. Quality control on MRI scanners has been performed since the early eighties and nowadays the ACR MRI phantom is being used for the accreditation of the scanners, and quality control of their qualitative performance. In this study the same phantom is being used to obtain quantitative values of three regions in the phantom that might be used as reference for quantitative quality control. The results of the scans provided quantitative values that can be used as reference for the quality control of qMRI, and there was no difference after scanning the same regions twice. Further study is recommended to provide quantitative values for different MRI scanners strength to assure the use of ACR phantom as a tool for quality control of qMRI scanners.
2031-01-02

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Martini, Julian. « Assesment of Market Potential of 3D Body Scanners within the Target Group of 3D Print Stores ». Master's thesis, Vysoká škola ekonomická v Praze, 2013. http://www.nusl.cz/ntk/nusl-198217.

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The world has recently witnessed the widespread of 3D printing technology. In the shadow of this development a new means of freezing time was born: 3D figurines. A 3D figurine is a mini version of oneself; a little sculpture manufactured by 3D Printers. These 3D figurines are sold for a profit by so called 3D Print Stores to consumers. For the production of such a 3D figurine one needs 3D Body Scanners. It is from the perspective of a producer of 3D Body Scanners that this master thesis was written. The objective was to establish whether or not the company should tap into that new market segment of 3D Print Stores. Furthermore a market entry strategy was to be developed. Thus a marketing research study was performed. For the analysis of the market segment primary and secondary data was scrutinized, which was gathered through expert interviews and desktop research. The primary scope of the study was limited to Germany. Overall the market segment proved to be promising, as consumers regard 3D figurines as a more sophisticated alternative to a digital photo. Competition is currently low, but the threat of new players entering the segment is high. Thus a market entry strategy was elaborated that suggests tapping into the market as fast as possible; thereby obtaining a first mover advantage and pre-empting market space. Furthermore a differentiation strategy was proposed to shield against growing competition.

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Macías, Montero José Gabriel. « VIPPIX : A readout ASIC for the next generation of human brain PET scanners ». Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663182.

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Positron emission tomography (PET) is a molecular imaging technique used for several decades in nuclear medicine that provides precise physiological information of the human body, what is crucial in oncology, cardiology, and neuropsychiatry. Due to physical, the best spatial resolution of PET is approximately 1 mm for human brain scanners. Unfortunately, the minimum resolution of the best commercial PET scanners for humans is 4-5 mm due to technological limitations. In this thesis, an application specific integrated circuit (ASIC) to readout the energy and the time stamp of a high-density and highly-granulated Cadmium Telluride detector for a novel PET scanner design is presented. The research presented here was realized within the framework of Voxel Imaging PET pathfinder ERC project to develop detector modules for positron emission tomography applications and reach their actual physical limits. The VIP PET scanner is based on the stacking of 2-mm thickness pixelated hybrid detectors. Every CdTe detector is pixelated into an array of 10 x 10 voxels of 1 mm x 1 mm x 2 mm size and is connected to a pixelated ASIC to readout independently the energy and the time stamp of every photon interaction. The VIP PET is based on more than 6 million voxels with independent energy and timing readout to reach the physical limits of PET. The simulated performance based on the properties of CdTe detectors shows a scatter fraction of approximately 4 % due to an excellent energy resolution of 1.6 % FWHM of the CdTe detectors. By simulation, the VIP PET is able to distinguish 1 mm size radioactive point-like source. The characterization of 2-mm thickness CdTe detectors using commercially available single-channel readout electronics is reported. Using a Sodium-22 radioactive source, the 511 keV photopeak resolution and the coincidence time resolution of back-to-back photons were measured with – 1000 V/mm detector bias voltage at -8 Celsius degree. An energy resolution of 1.6 % FWHM and a time coincidence resolution of 6 ns FWHM were obtained for photoelectric interactions. The architecture of the VIPPIX ASIC, i.e. the ASIC developed for VIP project, is based on an array of 10 x 10 independent pixel electronics controlled by a global controller and a common time to digital converter (TDC). Additional voltage and current references are generated in the ASIC’s back-end with a temperature sensor and a chip-ID cell. Every pixel electronics composes of a programmable gain preamplifier with detector’s leakage dynamic compensation, a tuneable peak-time pulse shaper connected to a peak-and-detect circuit, a 10-bit analog-to- digital converter (ADC), a pulse discriminator with adjustable offset, and a local pixel digital controller. The measured equivalent noise charge (ENC) of the pixel is 150 e- RMS and the trigger time jitter is approximately 1 ns for energy depositions larger than 200 keV. The time resolution of the integrated TDC is 600 ps FWHM. Twelve wafers of VIPPIX ASIC has been fabricated and characterized. Best quality ASICs have been mounted on 720 CdTe detectors and stacked in 18 detector modules with 40 hybrid detectors each to build the VIP PET prototype. Five modules have been characterized with a Sodium-22 radioactive source. The performance of approximately 18000 pixels shows a resolution of 2.2 % FWHM and a coincidence time resolution of 60 ns FWHM for 511 keV photopeak at -250 V/mm detector bias. Therefore, the main goal of the research has been accomplished. A new PET design based on pixelated Cadmium Telluride detectors using dedicated readout ASICs has been successfully fabricated, partly characterized, and is ready for image acquisition.

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Kessler, Mary Elaine Seeley Brett R. « Predicting the impact of full body scanners on air travel and passenger safety ». Monterey, California : Naval Postgraduate School, 2010. http://edocs.nps.edu/npspubs/scholarly/MBAPR/2010/Jun/10Jun%5FKessler%5FMBA.pdf.

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"Submitted in partial fulfillment of the requirements for the degree of Master of Business Administration from the Naval Postgraduate School, June 2010."
Advisor(s): Henderson, David R. ; Candreva, Philip. "June 2010." "MBA Professional report"--Cover. Description based on title screen as viewed on July 14, 2010. Author(s) subject terms: Privacy, Elasticity, Safety. Includes bibliographical references (p. 45-46). Also available in print.

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Kessler, Mary Elaine, et Brett R. Seeley. « Predicting the impact of full body scanners on air travel and passenger safety ». Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/10527.

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MBA Professional Report
Good decisions can be made only by looking at the full picture and accounting for what is seen and what is not seen. Air travel security measures aim to create more safety for the passenger; this is what is seen. What is not seen is the impact increased security measures create when passengers decide to substitute driving for flying. Traveling on a short-haul flight (under 500 miles) is significantly safer than driving that same distance in a vehicle. However, air travel security measures have led to more passengers choosing to substitute driving for flying due to longer wait times, greater inconvenience, and, in particular, the invasion of privacy. This study forecasts the impact full body scanners will have on air travel and passenger safety. Full body scanners invade one's privacy and, as a result, will negatively affect those passengers who place a high value on securing and maintaining their privacy. Passengers who substitute driving for flying will increase their risk level and increase the number of highway driving fatalities. The findings are that full body scanner usage at airports will increase annual highway driving fatalities from as few as 11 additional deaths to as many as 275.

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Souza, Fernando Luiz de. « Digitalização de radiografias odontologicas periapicais utilizando scanners e sua importancia na odontologia legal ». [s.n.], 2001. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290720.

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Orientador: Eduardo Daruge
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Através de estudos realizados, sabe-se da existência de diversos métodos de obtenção de radiografias digitais e digitalizadas; entretanto, alguns destes métodos são onerosos e trabalhosos. Sabe-se, ainda, que o uso dos arquivos digitais na odontologia estão em sua fase inicial. O objetivo deste estudo não é questionar o valor legal das Imagens digitais e sim apresentar as técnicas indiretas de digitalização de radiografias reduzindo o custo e facilitando a sua execução. Através do uso de dois scanners de marca e modelos diferentes procedemos a digitalização de 14 radiografias periapicais onde demonstramos a viabilidade das técnicas empregadas apontando vantagens de desvantagens de cada uma delas. A utilização do scanner de mesa nos forneceu melhores resultados quando comparado ao scanner de slides. A legalidade dos arquIvos digitais na odontologia é apenas uma questão de tempo. As técnicas apresentadas foram adaptadas para as necessidades do Cirurgião dentista e do Odontolegista e se fundamenta em princípios simples e básicos da imageologia digital. Baseado nesta simplicidade é possível acreditar que num futuro próximo os profissionais da odontologia poderão utilizar-se das técnicas apresentadas e desfrutarem dos benefícios trazidos com a informática
Abstract: Studies have shown the existence of various methods for the obtainment of digital and digitized radiographs; nevertheless, some of these methods are costly and difficult. It is also known that the use of digital files in Dentistry is still beginning. The purpose of this paper is not to call into question the legal vaI ue of digital lmages but otherwi se introduce indirect radiograph digitizing techniques, thus reducing cost and facilitating performance. Two scanners of different trademarks and models were used to digitize 14 periapical radiographs in order to demonstrate the practicability of the respective techniques, and the advantages and disadvantages of each. The table scanner provided better results when compared to the slide scanner. The legality of digital files in Dentistry is only a question of time. The techniques presented were adapted to the needs of the dentist and odontolegist and are based on simple and fundamental principIes of digital imaging, what lead us to believe that dentists will soon be able to use them and experience the benefits of informatics
Doutorado
Doutor em Odontologia Legal e Deontologia

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Burzynski, Jennifer Ann. « A Comparison of Digital Intraoral Scanners and Alginate Impressions : Time & ; Patient Satisfaction ». The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1489694607035837.

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Porter, Jason L. « Comparison of intraoral and extraoral scanners on the accuracy of digital model articulation ». VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4881.

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Introduction: Orthodontists increasingly rely on digital models in clinical practice. The ability of modern scanners to articulate digital models must be scientifically evaluated. Methods:Twenty five digital articulated models were produced from four digital scanners in five experimental groups. The resulting inter-arch measurements were compared to the gold standard. An acceptable range of 0.5mm more or less than the gold standard was used for evaluation. Results: iTero® and iTero® Element yielded all acceptable inter-arch measurements. The 3M™ True Definition and Ortho Insight 3D® with Regisil® bite registration produced four of six acceptable inter-arch measurements. The Ortho Insight 3D® with Coprwax ™ bite registration yielded three of six acceptable inter-ach measurements. Conclusions: The iTero® and iTero® Element produced the most accurately articulated models. The 3M™ True Definition and Ortho Insight 3D® with Regisil® were the next most accurate. The Ortho Insight 3D® scanner with Coprwax ™ was the least accurate method tested.

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Strandberg, Filip, et Johan Freij. « Measuring dimensions of goods modules with 2D laser scanners on a conveyor belt ». Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-138482.

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A company wants to measure and verify the size of goods modules, transported on a conveyor belt, with the help of two 2D laser scanners (LMS100). The resulting measurements will be written to a database whereafter the modules will be moved by an automatic lifting device to a storage. The dimensions and possible any protrusions need to be known to avoid collision. The goal with this project is to write three modular libraries. One library for communicating with the LMS100 scanner, one library for calculating the dimensions of the goods modules and one library for handling the database. A graphical user interface (GUI) was also created which was implemented with an existing graphical library, Simple Directmedia Layer (SDL). A Raspberry Pi 3 has been used as a hardware platform which communicates with two LMS100 via ethernet. All code is written in the programming language C. LMS100 communicates with so called telegrams and the library implements these with TCP sockets. The structure of these can be found in the manufacturer’s datasheet. The calculating library uses trigonometric functions with measurement values from the scanners. The database library uses sqlite3 for a serverless database. The testing of these libraries was first done on a small scale with only one scanner and a small box placed a few decimeters in front of the scanner, to verify the functionality of the libraries. The company later provided a larger test rig with a remote controlled platform, which drove between the scanners. When measuring objects with this test rig, the system showed an adequate ability to verify the size of the goods module. An inherent measurement error of a few millimeters of the scanners is shown, but this doesn’t affect the functionality in the final product which will measure considerably larger objects. Some functions are prepared for future development but aren’t yet ready for use. The protrusions of the goods modules aren’t yet discovered by the system. The calculating library is prepared to be able to detect these, but the evaluation of them aren’t ready. If the goods module is at an angle, the system measurements will be faulty. For every scanned segment the coordinates are saved and in future development it will be able to detect the angle.
Ett företag vill med hjälp av två stycken 2D-laserskannrar (LMS100) mäta och verifiera storleken på godsmoduler som transporteras på ett transportband. Mätresultatet ska skrivas till en databas varefter modulerna med en automatiskt styrd avlastare förflyttar dem till ett lager. Dimensioner och eventuella utstick på modulen måste vara kända för att undvika kollision. Målet med arbetet är att skriva tre stycken modulära bibliotek. Ett bibliotek för kommunikation med LMS100, ett bibliotek för beräkning av godsmodulens dimensioner och ett bibliotek för databashantering. Till detta skapades även ett grafiskt användargränssnitt (GUI) som implementerades med hjälp av ett färdigt grafikbibliotek, Simple Directmedia Layer (SDL). En Raspberry Pi 3 har använts som hårdvaruplattform som kommunicerar med två stycken LMS100 via ethernetanslutning. All kod skrivs i programspråket C. LMS100 kommunicerar med s.k. telegram och biblioteket implementerar dessa via TCP sockets. Strukturen på dessa går att läsa i tillverkarens datablad. Beräkningsbiblioteket använder trigonometriska funktioner med mätvärden från skannrarna för beräkning. Databasbiblioteket använder sig av sqlite3 för en serverlös databas. Testning av dessa bibliotek skedde först på en småskalig nivå med endast en skanner och en liten låda placerad några decimeter framför skannern, för att verifiera funktionaliteten på berörda bibliotek. Företaget bidrog senare med en testrig i större skala med en fjärrstyrd plattform, som körde mellan de två skannrarna. Vid mätning av objekt i denna testrig visade systemet en tillräckligt god förmåga för att kunna verifiera storlek på godsmoduler. Ett medföljt mätfel i millimeterskala finns i skannrarna, men detta påverkar inte funktionaliteten i den slutgiltiga produkten som ska mäta mycket större objekt. Vissa funktioner är förberedda för framtida utveckling men är inte färdiga för användning. Utstick på godsmodulerna upptäcks inte av systemet än. Beräkningsbiblioteket är förberett för att kunna upptäcka dessa, men utvärderingen av dem är inte färdigt. Om godsmodulen är vriden på transportbandet mäter systemet fel. Koordinater finns för varje skannat segment så att man ska kunna upptäcka denna vinkel i framtida utveckling.

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Jain, Ankur. « Low voltage, MEMS-based reflective and refractive optical scanners for endoscopic biomedical imaging ». [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0015728.

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Thèses sur le sujet « LE. Scanners »

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