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 "luminance distribution" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-7 z 7
    Tytuł:
    Advanced modelling and luminance analysis of LED optical systems
    Autorzy:
    Słomiński, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/200561.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    lighting technology
    luminance distribution
    luminance modelling
    LED
    optical systems design
    Opis:
    Designing, optimizing and analyzing optical systems as part of the implementation process into production of modern luminaires require using advanced simulation and computational methods. The progressive miniaturization of LED (light emitting diode) chips and growth in maximum luminance values, achieving up to 108 cd/m2, require constructing very accurate geometries of reflector and lens systems producing complex luminous intensity distributions while reducing discomfort glare levels. Currently, the design process cannot function without advanced simulation methods. Today’s simulation methods in the lighting technology offer very good results as far as relatively large conventional light sources such as halogen lamps, metal halide lamps and high pressure sodium lamps are concerned. Unfortunately, they often fail in the case of chip-on-board LED light sources whose luminous surface dimensions are increasingly often contained inside a cube of the side length below 1mm. With the high sensitivity of such small chips and lenses with dimensions ranging from a just a few to between 10 and 20 mm, which is presented in this paper, modern luminance distribution measurement methods, luminance modelling and ray tracing methods should be used to minimize any errors arising from incorrectly projecting the design in the final physical model. Also, very importantly, focus should be directed towards reducing a chance of making a mistake while collimating the position of the light source inside the optical system. The paper presents a novel simulation calculation method enriched with an analysis of optical system sensitivity to a light source position. The results of simulation calculations are compared with the results of laboratory measurements for corresponding systems.
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 6; 1107-1116
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Small lighting luminaires for illumination applications
    Autorzy:
    Różowicz, Tadeusz
    Wachta, Henryk
    Różowicz, Sebastian
    Powiązania:
    https://bibliotekanauki.pl/articles/2172806.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    computer visualization
    illumination
    LED light sources
    luminance distribution
    Opis:
    The application of solid-state light sources in luminaires creates a new quality in illumination design works. In a confrontation with a commonly used but relatively unattractive flood method, the use of small-size luminaires allows one to present an illuminated architectural object in a more attractive way in the evening and at night. In this case, it is possible to apply the principles of illumination described in the literature, especially the principle of height amplification and the principle of depth amplification. The conceptual work of illumination with the use of a large number of small-size luminaires does not require the use of supporting graphical tools, but the specification of actual lighting equipment using only polygonal samples in this case is not possible. The paper presents selected issues of the key stages of the completed work. Using specialized computer software, a geometric model of the architectural object has been developed, facade materials have been parameterized, models of small-size illuminating equipment have been selected and, finally, calculations of luminance distribution on illuminated surfaces have been carried out. As a result of computer work, luminance distributions and photorealistic visualizations of illuminations from defined main directions of observation were obtained. The Lubomirski Palace in Przemysl is an example of the architectural object indicated for detailed works.
    Źródło:
    Archives of Electrical Engineering; 2022, 71, 4; 1035--1050
    1427-4221
    2300-2506
    Pojawia się w:
    Archives of Electrical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    A two-layer neural system for reduced-reference visual quality assessment
    Autorzy:
    Redi, J.
    Gastaldo, P.
    Zunino, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/91584.pdf
    Data publikacji:
    2011
    Wydawca:
    Społeczna Akademia Nauk w Łodzi. Polskie Towarzystwo Sieci Neuronowych
    Tematy:
    reduced-reference system
    image
    visual quality assessmen
    luminance distribution
    visual distortions
    support vector machines
    SVM
    Opis:
    Real-time assessment of visual quality can be efficiently supported by reduced-refe-rence paradigms, which require a very limited amount of information on the original signal, easily embeddable in the signal itself. In this paper, a reduced-reference system for image quality assessment is proposed, based on a small sized numerical description of images encoding the luminance distribution and its variations due to visual distortions. The assessment paradigm is implemented exploiting machine learning tools and articulates in two phases: first, a Support Vector Machines-based classifier identifies the kind of distortion affecting the image; then, the actual quality level of the distorted image is computed by a specifically trained SVM regressor. The general validity of the approach is supported by experimental validations based on subjective quality data.
    Źródło:
    Journal of Artificial Intelligence and Soft Computing Research; 2011, 1, 1; 27-41
    2083-2567
    2449-6499
    Pojawia się w:
    Journal of Artificial Intelligence and Soft Computing Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Digital luminance photometry in the context of the human visual system
    Autorzy:
    Słomiński, Sebastian
    Powiązania:
    https://bibliotekanauki.pl/articles/2173705.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    human vision
    luminance distribution measurements
    glare
    lighting technology
    widzenie ludzkie
    pomiar rozkładu luminancji
    blask
    technologia oświetleniowa
    Opis:
    Almost all solutions in modern lighting systems are based on LED technology. Luminance and obvious ease of control are the key characteristics of this light source. At the same time, luminances at the level of 108 cd/m2 are a significant advantage of LED in design applications, where high luminous intensity amplification is important. However, in general and in road lighting applications, LED luminaires represent a source of potential discomfort glare. Unfortunately, lighting technology’s metrology lags behind LED parameter development and optimization. The results of luminance measurements of the same luminaires, made with a luminance camera and meters with a measuring field, differ. The differences even appear for the same imaging luminance measuring devices with different lenses. This article presents the results of experiments and detailed analyzes related to modern digital luminance photometry based on the use of digital image sensors. Luminance tests were conducted on multi-source research models of luminaires. Traditional luminance measuring equipment with a measuring field was used in the experiment. The research was also supplemented with the measurements made using CCD/CMOS luminance cameras with selected components where the angular field of view of each pixel was a 0.45 min arc corresponding to the highest average human sight parameters. The results confirm that the average luminance value for multi-source luminaires depends on the measurement system configuration. It has been proposed to standardize the angular field of view parameters of all measurement systems, where the measurement aims to obtain a value that directly relates to human visual impressions (e.g. glare).
    Źródło:
    Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 5; art. no. e143103
    0239-7528
    Pojawia się w:
    Bulletin of the Polish Academy of Sciences. Technical Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Standard sky calculations for daylighting design and energy performance purposes
    Autorzy:
    Darula, S.
    Kittler, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/362573.pdf
    Data publikacji:
    2009
    Wydawca:
    Instytut Fizyki Budowli Katarzyna i Piotr Klemm
    Tematy:
    światło dzienne
    rozkład luminacji nieba
    wzorcowy warunek światła dziennego
    symulacja światła dziennego
    obliczenia luminacji nieba
    daylighting
    sky luminance distribution
    standard daylight conditions
    daylighting simulations
    sky luminance calculation
    Opis:
    Daylight is important in the design of the healthy and energy efficient indoor environment. Until now the main criterion for indoor daylighting evaluation is the Daylight Factor assuming exterior overcast sky conditions. This criterion represents minimum daylight availability needed for visual tasks and work processes. However, various outdoor daylight situations can occur during any year including also sunny, cloudy, foggy states etc. The classification of sky luminance distributions that occur in nature was done and fifteen typical sky patterns were proposed for standardisation. This result was adopted and published as ISO 15469:2004/CIE S011/E:2003 Spatial distribution of daylight - CIE Standard general sky. The standard allows to calculate typical relative sky luminance distribution which can serve to predetermine sky luminances and exterior daylight illuminance in arbitrary time and locality. The ISO/CIE Standard General Sky concept is presented together with sky luminance calculations in relative and absolute photometric units. Such an approach can orientate building physic research activities to find new criteria, methods and procedures for daylight evaluations in interiors considering more realistic daylight conditions.
    Źródło:
    Fizyka Budowli w Teorii i Praktyce; 2009, T. 4; 23-28
    1734-4891
    Pojawia się w:
    Fizyka Budowli w Teorii i Praktyce
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Measurements of spectral spatial di stribution of scattering materials for rear projection screens used in virtual reality systems
    Autorzy:
    Mazikowski, A.
    Trojanowski, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/220880.pdf
    Data publikacji:
    2013
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    scattering distribution function
    BSDF
    virtual reality
    CAVE
    spectroscopy
    luminance
    Opis:
    Rapid development of computing and visualisation systems has resulted in an unprecedented capability to display, in real time, realistic computer-generated worlds. Advanced techniques, including three-dimensional (3D) projection, supplemented by multi-channel surround sound, create immersive environments whose applications range from entertainment to military to scientific. One of the most advanced virtual reality systems are CAVE-type systems, in which the user is surrounded by projection screens. Knowledge of the screen material scattering properties, which depend on projection geometry and wavelength, is mandatory for proper design of these systems. In this paper this problem is addressed by introducing a scattering distribution function, creating a dedicated measurement setup and investigating the properties of selected materials used for rear projection screens. Based on the obtained results it can be concluded that the choice of the screen material has substantial impact on the performance of the system.
    Źródło:
    Metrology and Measurement Systems; 2013, 20, 3; 443-452
    0860-8229
    Pojawia się w:
    Metrology and Measurement Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Wybrane rozwiązania przegrody doświetlającej w pomieszczeniu przeznaczonym do pracy umysłowej
    Some solutions of transparent partition in the room intended for intellectual work
    Autorzy:
    Heim, D
    Jędrzejuk, H
    Szczepańska, E
    Powiązania:
    https://bibliotekanauki.pl/articles/362994.pdf
    Data publikacji:
    2011
    Wydawca:
    Instytut Fizyki Budowli Katarzyna i Piotr Klemm
    Tematy:
    światło dzienne
    natężenie oświetlenia
    luminancja
    komfort wizualny
    symulacja
    daylight
    illuminance distribution
    luminance
    visual comfort
    simulation
    Opis:
    W pracy podjęto próbę oceny jakości środowiska wewnętrznego w miejscu pracy umysłowej, pod kątem komfortu wizualnego oraz zaproponowanie rozwiązań alternatywnych. Wybrano istniejące pomieszczenie czytelni, przeznaczonej do pracy z tradycyjnymi materiałami piśmiennymi oraz/lub komputerem. Ocenę dokonano na podstawie wyników pomiarów in situ, analizy obrazów cyfrowych oraz analizy numerycznej dla opracowanego modelu komputerowego. Przeprowadzono analizy zmodyfikowanych rozwiązań fasady pod kątem spełnienia wymagań użytkowych. Porównywanymi parametrami były: luminancja poszczególnych powierzchni oraz natężenie oświetlenia na blatach roboczych.
    The assessment of visual comfort in an existing room dedicated to intellectual work is presented in a paper. Initially, some measurement in situ have been done. Than based on the obtained results computer model were developed and validated. Finally, for alternative solutions were proposed. Simulation were conducted for four periods of the year, the days representing four season. Results were concluded at the end of the paper based on illuminance level and luminance distribution.
    Źródło:
    Fizyka Budowli w Teorii i Praktyce; 2011, T. 6, nr 3, 3; 17-22
    1734-4891
    Pojawia się w:
    Fizyka Budowli w Teorii i Praktyce
    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