Wyniki wyszukiwania - BazTech

1

Factors Influencing Accuracy of Estimating Position of Objects in a Multi-camera System

Klimaszewski Krzysztof, Grajek Tomasz, Wegner Krzysztof

Journal of Telecommunications and Information Technology

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2024

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nr 2

1--16

EN

Nowadays, research focusing on robotics, autonomous vehicles, and scene analysis shows a clear need for the ability to accurately reconstruct three-dimensional environments. One of the methods allowing to conduct such a reconstruction is to use a set of cameras and image processing techniques. This is a passive method. Despite being, in general, less accurate than its active counterparts, it offers significant advantages in numerous applications in which active systems cannot be deployed due to limited performance. This paper provides a theoretical analysis of the accuracy of estimating 3D positions of objects present at a given scene, based on images from a set of cameras. The analysis assumes a known geometrical configuration of the camera system. The important limiting factor in the considered scenario is the physical resolution of sensors - especially in the case of systems that are supposed to work in real time, with a high FPS rate, as the use of high-resolution cameras is difficult in such circumstances. In the paper, the influence of the geometric arrangement of the cameras is studied and important conclusions about the potential of three-camera configurations are drawn. The analysis performed and the formulas derived help predict the boundary accuracy values of any system using a digital camera. The results of an experiment that confirm the theoretical conclusions are presented as well.

2

Związki kompleksowe na bazie Gd(III), W(IV), Mn(II), Eu(III) i 99mTc wykorzystywane w diagnostyce medycznej

Pobłocki Kacper, Drzeżdżon Joanna, Jacewicz Dagmara Elżbieta

Wiadomości Chemiczne

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2022

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[Z] 76, 9-10

803--823

EN

Recently, hospitals have undergone major changes. Minimally invasive surgery is becoming more common, and numerous innovations are emerging, such as interventional radiology (IVR) and hybrid surgery. In order to keep pace with changes in this extremely dynamic field, scientist keep working on the development of imaging technology and the improvement of image display devices and new compounds acting as contrast agent (CA). In medicine, metals are used for diagnostic and therapeutic purposes. Inorganic elements are increasingly used as contrast agents in medical imaging due to their unique physicochemical properties. In this review, we would like to focus on the latest literature reports that contain information on Gd(III), W(IV), Mn(II), Eu(III) and 99mTc used in medical diagnostics.

3

Underwater Laser Imaging

Metoyer Shelby, Bogucki Darek

Polish Hyperbaric Research

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2021

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nr 4(77)

39--52

EN

Attenuation of light in the ocean ranges widely depending on the environment and is especially significant in optical remote sensing. Absorption of light by ocean water limits the range light can travel before being extinguished. The complex interactions of scattering light and ocean water often lead to distortions of the signal as it propagates which degrades the quality and accuracy of underwater measurements. Consequently, underwater visibility (i.e. how well an object can be seen with definition at distance) can be less than 1 [m] in turbid and murky environments such as harbors. Advancements in laser imaging systems make highly accurate measurements at further ranges than has previously been possible through temporally filtering of a modulated laser signal at frequencies as high as 1 [GHz]. Here we overview the processes affecting underwater light propagation and visibility, laser imaging systems, recent advancements in the field of underwater optical imaging, and the application of such systems.

PL

Tłumienie światła w oceanie waha się w szerokim zakresie w zależności od środowiska i jest szczególnie istotne w teledetekcji optycznej. Absorpcja światła przez wodę oceaniczną ogranicza zasięg, jaki światło może pokonać, zanim zgaśnie. Złożone interakcje rozpraszania światła i wody oceanicznej często prowadzą do zniekształceń sygnału podczas jego propagacji, co obniża jakość i dokładność pomiarów podwodnych. W związku z tym widoczność podwodna (tj. to, jak dobrze można zobaczyć obiekt z określoną odległością) może być mniejsza niż 1 [m] w mętnych i mętnych środowiskach, takich jak porty. Postępy w laserowych systemach obrazowania umożliwiają bardzo dokładne pomiary w większych zakresach niż było to wcześniej możliwe dzięki czasowemu filtrowaniu modulowanego sygnału laserowego przy częstotliwościach sięgających nawet 1 [GHz]. Tutaj dokonujemy przeglądu procesów wpływających na propagację i widoczność światła podwodnego, systemy obrazowania laserowego, najnowsze postępy w dziedzinie podwodnego obrazowania optycznego oraz zastosowanie takich systemów.

4

Badania geofizyki otworowej na potrzeby budowy tuneli

Roguska Emilia

Materiały Budowlane

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2020

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nr 2

5--7

PL

Geofizyka otworowa jest bardzo dynamicznie rozwijającym się narzędziem badań geologicznych. Choć wykorzystuje się ją głównie w przypadku poszukiwania złóż naturalnych, to jej metody mogą także dostarczyć wielu ważnych danych przydatnych przy budowie tuneli. W artykule omówione zostały główne grupy metod badań geofizyki otworowej oraz ich zastosowanie w rozpoznaniu geotechnicznym. Podano przykłady metod najczęściej wykorzystywanych przy badaniach geologiczno-inżynierskich oraz omówiono ich zasady.

EN

Well-logging is one of the most dynamically developing method of geological investigation. It is mainly used for the purposes of oil and gas exploration, still it brings a lot of informative data for tunnel design. The article describes the main methods of well-logging and their application in geotechnical investigation. The examples of methods used for this purpose were presented and the principles of their operation were discussed.

5

Illumination method for high resolution imaging

Watanabe K.

Optica Applicata

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2011

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Vol. 41, nr 1

135--144

EN

Annularly distributed light is proposed to increase the spatial resolution when observing a water surface. When light with an annular distribution is used to illuminate the entrance pupil of an objective lens, an air -water interface can be illuminated with a Bessel beam, which is a focused beam formed by plane wave components at the same angle. If the optimum size and width of the annular light and radial polarization are chosen, a microscopic distribution is obtainable from the reflected light intensity. It is theoretically shown that the reflectance changes with the width of annular light and this allows to make water surface measurements. In order to clarify the spatial resolution, the electric field intensity distribution on the focusing plane is also calculated. From the full width at half maximum of the calculated distribution, it is shown that the annularly distributed light increases the spatial resolution by increasing the radius of the annular light and decreasing the wavelength of the light. It is also shown that a spatial resolution of a few hundred nanometers is achievable.

6

Testing of plano-optical elements

Mikš A., Novák J.

Optica Applicata

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2003

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Vol. 33, nr 2-3

391-402

EN

The most common criteria of the quality of optical surfaces and elements are analysed in detail in this paper. Both geometrical-optics criteria and diffraction criteria are defined. The connection between different criteria is also described. Some terms lacking classical analogy in optics are described, e.g., the focal length of the plane parallel plate, prism, etc