Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "3D surfaces" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-7 z 7
    Tytuł:
    Dedicated 3D geometrical models for representing anatomical structures
    Autorzy:
    Sequeira, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/333209.pdf
    Data publikacji:
    2003
    Wydawca:
    Uniwersytet Śląski. Wydział Informatyki i Nauki o Materiałach. Instytut Informatyki. Zakład Systemów Komputerowych
    Tematy:
    model geometryczny
    struktury 3D
    powierzchnia swobodna
    niejawne powierzchnie
    przedstawienie struktur anatomicznych
    geometrical modeling
    3D structures
    free-form surfaces
    implicit surfaces
    representation of anatomical structures
    Opis:
    The representation of anatomical structures requires to take into account their topological features such as their morphological ones. Differential geometrical properties also have to be managed through the associated 3D models. Unfortunately, classical geometrical modeling approaches do not provide these possibilities. In this paper, we describe two original approaches that bring a solution to this problem for the representation of tree-like cavities - such as vascular ones - and complex organs - such as the heart. Medical applications were given as an illustration of the use of two new approaches discussed bellow.
    Źródło:
    Journal of Medical Informatics & Technologies; 2003, 5; IP3-12
    1642-6037
    Pojawia się w:
    Journal of Medical Informatics & Technologies
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    3D modelling and segmentation with discrete curvatures
    Autorzy:
    Bac, A.
    Daniel, M.
    Maltret, J. - L.
    Powiązania:
    https://bibliotekanauki.pl/articles/333880.pdf
    Data publikacji:
    2005
    Wydawca:
    Uniwersytet Śląski. Wydział Informatyki i Nauki o Materiałach. Instytut Informatyki. Zakład Systemów Komputerowych
    Tematy:
    powierzchnie wielościenne
    krzywe dyskretne
    analiza kształtu
    modelowanie 3D
    segmentacja
    polyhedral surfaces
    discrete curvatures
    shape analysis
    3D modelling
    segmentation
    Opis:
    Recent concepts of discrete curvatures are very important for Medical and Computer Aided Geometric Design applications. A first reason is the opportunity to handle a discretisation of a continuous object, with a free choice of the discretisation. A second and most important reason is the possibility to define second-order estimators for discrete objects in order to estimate local shapes and manipulate discrete objects. There is an increasing need to handle polyhedral objects and clouds of points for which only a discrete approach makes sense. These sets of points, once structured (in general meshed with simplexes for surfaces or volumes), can be analysed using these second-order estimators. After a general presentation of the problem, a first approach based on angular defect, is studied. Then, a local approximation approach (mostly by quadrics) is presented. Different possible applications of these techniques are suggested, including the analysis of 2D or 3D images, decimation, segmentation... We finally emphasise different artefacts encountered in the discrete case.
    Źródło:
    Journal of Medical Informatics & Technologies; 2005, 9; 13-24
    1642-6037
    Pojawia się w:
    Journal of Medical Informatics & Technologies
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Metody całkowania numerycznego pola gradientu w inspekcji wizualnej powierzchni narzędzi ściernych z użyciem Photometric Stereo
    Numerical gradient field integration methods in task of visual inspection of abrasive tools surfaces by means of Photometric Stereo
    Autorzy:
    Bernat, A.
    Kacalak, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/158228.pdf
    Data publikacji:
    2008
    Wydawca:
    Stowarzyszenie Inżynierów i Techników Mechaników Polskich
    Tematy:
    inspekcja wizualna
    Photometric Stereo
    całkowanie numeryczne
    rekonstrukcja 3D
    powierzchnie narzędzi ściernych
    visual inspection
    numerical integration
    abrasive tools surfaces
    3D reconstruction
    Opis:
    W tym referacie zaprezentowano pewne schematy sprawnego i niezawodnego numerycznego całkowania przestrzennego zawartości dyskretnego pola gradientu. Przegląd poprzedzono wstępnymi rozdziałami dotyczącymi zagadnień photometric stereo, w inspekcji wizualnej rzeczywistych powierzchni, z naciskiem kładzionym na możliwe zastosowania podejścia monoskopowego oraz wieloobrazowego w bezstykowej ilościowej estymacji powierzchni o tak zróżnicowanej strukturze geometrycznej, jakimi są powierzchnie narzędzi ściernych.
    In this paper some schemes of efficient and robust numerical spatial integration of the discrete gradient field contents have been presented. The survey follows introductory chapters, related to photometry stereo problems, in visual inspection of real surfaces, with stress put on possible applications of monoscopic and multiimage approach in contactless quantitative estimation of such textured surfaces, like these of abrasive tools.
    Źródło:
    Pomiary Automatyka Kontrola; 2008, R. 54, nr 7, 7; 404-408
    0032-4140
    Pojawia się w:
    Pomiary Automatyka Kontrola
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Geomorfometria - parametry morfometryczne w charakterystyce rzeźby terenu
    The Morphometric Relief Characteristic on a Basis of Digital Terrain Models
    Autorzy:
    Wieczorek, M.
    Żyszkowska, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/204516.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Geograficzne
    Tematy:
    geomorfologia
    analiza przestrzenna
    NMT
    powierzchnie 3D
    GIS
    geomorfometria
    geomorphology
    spatial analyses
    DTM
    3D surfaces
    geomorphometry
    Opis:
    Autorki przedstawiają geomorfometrię jako dziedzinę związaną z określaniem morfometrycznych cech powierzchni terenu, jej podstawowe problemy oraz metody oparte na numerycznych modelach terenu.
    Morphometry, which has been accompanying geography sińce 19th century, establishes numerical parameters describing Earth surface relief. Every type of measurement is conditioned by certain methodological assumptions which determine the way they are conducted. In the process it is very important to adjust the scale of the elaboration to the size of forms under analysis and to the goal of research. The choice of the size of reference units in which morphometric parameters are determined is equally essential. A.F. Pitty (1969), A.J.W. Gerard and DA. Robinson (1971) stressed the relation between the calculated slope angle and the size of the interval in which the angle is measured, even during measurements in open terrain. Morphometric parameters in traditional morphometry were determined on the basis of contour-line image of relief. Slope and slope aspect were then determined. Nowadays, the parameters are calculated on the basis of digital terrain models in the form of TIN or GRID. The article presents the algorithms for calculation of slope and slope aspect with the use of raster model. Depending on the number of adjacent grids considered in calculations, the algorithms for the determination of slope and slope aspect base on two, three, four, eight and nine points (P.L. Guth 1995). Among basic attributes of topographic surface describing the shape of the slope is surface curvature,
    Źródło:
    Polski Przegląd Kartograficzny; 2011, T. 43, nr 2, 2; 130-144
    0324-8321
    Pojawia się w:
    Polski Przegląd Kartograficzny
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The three-dimensional imaging of rock wall surface with the use of computer-based image processing and analysis
    Autorzy:
    Oleszko, K.
    Młynarczuk, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/178560.pdf
    Data publikacji:
    2015
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    rock surfaces
    image analysis
    3D imaging
    profilometry
    Opis:
    The paper presents two methods of digital mapping of rock walls in three dimensional space. The methods have been developed with the use of low-cost devices, which enable image acquisition, and processing methods based on digital image processing and analysis. Both methods are based on so-called shadow profilometry. One of those methods involved mapping the shape of the rock wall on casted mapped surface with analyzed laser lines. The second method was based on the analysis of projected set of bit planes. The planes were projected by computer projector. Both measurement methods have been tested in Miękinia porphyry quarry. The study involved rock wall measurements, which were repeated several times. The part of rock material was removed from the measured wall after each measurement. In order to verify the accuracy of the proposed methods of measurement, volume results obtained and based on digital methods were compared to the volume of removed rock material during measurement. Calculated results were characterized by small deviations which prove to be correct, and are a solid basis for further work on practical application of presented methods.
    Źródło:
    Studia Geotechnica et Mechanica; 2015, 37, 1; 53-58
    0137-6365
    2083-831X
    Pojawia się w:
    Studia Geotechnica et Mechanica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of different approaches to 3D numerical model development of the contact zone between elementary asperities and flat surface
    Autorzy:
    Maciolka, P.
    Jedrzejewski, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/99568.pdf
    Data publikacji:
    2017
    Wydawca:
    Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
    Tematy:
    flat surfaces
    contact
    roughness
    FEM
    3D model
    Opis:
    This paper presents two triaxial finite element (FE) models: a “full model” and a “quarter model”, representing the contact between the specimen’s rough surface and the ideally smooth and flat surface of the punch. Models have a contact zone that represents the topography of the real surface and has elastoplastic properties close to those of the real contact. The contact zone was entirely modelled on the basis of roughness measurements performed on a real milled specimen made of 5083 aluminium alloy. The developmentof the FE models, the stages in their refinement and the interlinking of the contact zone with the material of the specimen are described. The results of the computed deformations occurring during the specimen contact loading with the punch were compared with the experimental results. The possible causes of the observed deviations of the computer simulation results from the experimental ones were discussed. The models were used to analyse the effect of the specimen’s material properties, i.e. Young’s modulus, yield strength, compressive strength and material hardening, on the deformations in the contact. On this basis a procedure for predicting the parameters describing the contact characteristic in cases of changes in the properties of the subsurface zone is proposed.
    Źródło:
    Journal of Machine Engineering; 2017, 17, 4; 40-53
    1895-7595
    2391-8071
    Pojawia się w:
    Journal of Machine Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    3D scan contour de-featuring for improved measurement accuracy – a case study for a small turbine guide vane component
    Autorzy:
    Jamontt, Marcin
    Pyrzanowski, Paweł
    Powiązania:
    https://bibliotekanauki.pl/articles/2086866.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    3D scan
    flatness
    turbine guide vane
    small surfaces
    point clouds
    contour recognition
    contour de-featuring
    skanowanie 3D
    płaskość
    łopatka prowadząca turbiny
    powierzchnie małe
    chmura punktów
    rozpoznawanie konturów
    usuwanie konturów
    Opis:
    3D scanning measurements are gaining popularity every year. Quick inspections on already captured point clouds are easy to prepare with the use of modern software and machine learning. To achieve repeatability and accuracy, some surface and measurement issues should be considered and resolved before the inspection. Large numbers of manufacturing scans are not intended for manual correction. This article is a case study of a small surface inspection of a turbine guide vane based on 3D scans. Small surface errors cannot be neglected as their incorrect inspection can result in serious faults in the final product. Contour recognition and deletion seem to be a rational method for making a scan inspection with the same level of accuracy as we have now for CMM machines. The main reason why a scan inspection can be difficult is that the CAD source model can be slightly different from the inspected part. Not all details are always included, and small chamfers and blends can be added during the production process, based on manufacturing standards and best practices. This problem does not occur during a CMM (coordinate measuring machine) inspection, but it may occur in a general 3D scanning inspection.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 5; e138815, 1--8
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-7 z 7

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies