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 "conditions of extreme" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-5 z 5
    Tytuł:
    Selection of materials and development of technology for the production of elements used in conditions of extreme tribological wear
    Autorzy:
    Wilk-Kołodziejczyk, D.
    Pirowski, Z.
    Grudzień-Rakoczy, M.
    Bitka, A.
    Chrzan, T.
    Powiązania:
    https://bibliotekanauki.pl/articles/2079807.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    innovative casting technologies
    wear
    selection of materials
    conditions of extreme
    shell mold
    innowacyjne technologie odlewnicze
    zużycie tribologiczne
    dobór materiałów
    warunki ekstremalne
    Opis:
    Work was done as a part of the project " New generation haulage system of highly productive longwall systems" aiming to develop and implement a new longwall shearer system called KOMTRACK. The widely used EICOTRACK feed system developed forty years ago is not adapted to modern longwall shearers' power. Within the project, an innovative, flexible feed system with a modular structure was created with the possibility of continuous adjustment to the carbon wall's unevenness. Newly-developed three cast steels variants have been initially selected to fabricate this system's elements. The material's final selection was realized based on the tensile tests, Charpy impact tests, Brinell hardness surveys, and wear resistance measurements. Results analysis allowed to select cast steel marked as "2", which fulfilled all requirements and was used in further casting trials.
    Źródło:
    Archives of Foundry Engineering; 2021, 21, 4; 47-54
    1897-3310
    2299-2944
    Pojawia się w:
    Archives of Foundry Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Graniczne dystrybuanty wartości ekstremalnych dla zależnych ciągów zmiennych losowych
    Limiting distribution function of extreme values for the dependent sequences random variables
    Autorzy:
    Kuźmiński, Łukasz
    Powiązania:
    https://bibliotekanauki.pl/articles/425143.pdf
    Data publikacji:
    2013
    Wydawca:
    Wydawnictwo Uniwersytetu Ekonomicznego we Wrocławiu
    Tematy:
    order statistics
    limiting distribution function of extreme
    dependence conditions D(un) and D’(un)
    extreme index
    Opis:
    In the article the outline of asymptotic theory of extreme values has been intro-duced for the application to finance, hydrology and insurance. The study includes the theo-rems and the definitions which give the possibility to appoint the limiting distribution func-tion for the distributions of maximum in three cases. The first case concerns the sequence independent random variables. The second case concerns the stationary processes of random variables for which the conditions D(un) and D’(un) are satisfied (i.e. “the extinguishing de-pendence”). The last case concerns the stationary processes for which the conditions D(un) and D’(un) are not satisfied.
    Źródło:
    Econometrics. Ekonometria. Advances in Applied Data Analytics; 2013, 2(40); 115-125
    1507-3866
    Pojawia się w:
    Econometrics. Ekonometria. Advances in Applied Data Analytics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Model działania schładzacza spalin silnika turbinowego w ekstremalnych lotach śmigłowca. Część 2. Symulacja działania schładzacza spalin w ekstremalnych warunkach lotu śmigłowca
    Performance model of turbine engine exhaust cooler in extreme conditions helicopter flights. Part 2. Performence simulation of exhaust cooler in helicopter flight extreme conditions
    Autorzy:
    Fijałkowski, S.
    Wójcik, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/213896.pdf
    Data publikacji:
    2008
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
    Tematy:
    lotnictwo
    śmigłowce
    schładzacz spalin silnika turbinowego
    ekstremalne loty śmigłowca
    aviation
    helicopters
    model of turbine engine exhaust cooler
    extreme conditions helicopter flights
    Opis:
    W pracy przedstawiono wyniki symulacji komputerowej działania dobudowanego schładzacza eżekcyjnego spalin, współdziałającego z silnikiem 10W śmigłowca PZL W3 Sokół. Symulacje przeprowadzono dla ekstremalnych warunków lotu śmigłowca, wykorzystując wyniki prób w wybranych manewrach lotu NOE. Opracowany program obliczeniowy obejmuje obliczanie parametrów termicznych i gazodynamicznych spalin na wylocie z kolektora, a także obliczanie procesu schładzania spalin w schładzaczu. W wyniku symulacji uzyskuje się wartości temperatury i ciśnień cząstkowych mieszaniny spalin i powietrza odpływających do otoczenia. Są one przydatne w dalszym postepowaniu do oceny poziomów emisji podczerwieni.
    This paper presents the results of computer simulation activities of add-on ejection exhaust cooler, working with 10W engine of PZL W-3 Sokół helicopter. Simulation was performed for the extreme helicopter flight conditions, using the results of trials in selected NOE flight maneuvers. Developed calculation program includes the calculation of thermal and gasdynamic parameters of exhaust gases at the collector outlet, and the calculations of the gases cooling processes in the cooler. As a result of the simulation are obtained temperatures and partial pressures of the exhaust and air mixture outflowing to the environment. They are useful in further investigation to assess the levels of infrared emissions.
    Źródło:
    Prace Instytutu Lotnictwa; 2008, 3-4 (194-195); 229-239
    0509-6669
    2300-5408
    Pojawia się w:
    Prace Instytutu Lotnictwa
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Model działania schładzacza spalin silnika turbinowego w ekstremalnych lotach śmigłowca. Część 1: Identyfikacja współdziałania bezprzeponowego schładzacza spalin z silnikiem turbinowym śmigłowca
    performance model of turbine engine exhaust cooler in extreme conditions helicopter flights. Part 1. Identification of membranneless exhaust gas cooler interaction with the helicopter turbine engine
    Autorzy:
    Fijałkowski, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/213900.pdf
    Data publikacji:
    2008
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Lotnictwa
    Tematy:
    lotnictwo
    śmigłowce
    schładzacz spalin silnika turbinowego
    silnik turbinowy
    loty ekstremalne śmigłowca
    aviation
    helicopters
    model of turbine engine exhaust cooler
    extreme conditions helicopter flights
    Opis:
    W artykule przedstawiono model współdzialania bezprzeponowego, dekcyjnego schładzacza spalin z turbinowym silnikiem śmigłowca w aspekcie obniżania temperatur zmian udziałów CO2 i H20 w mieszaninie spalin i powietrza emitowanej do otoczenia. Tematyka pracy dotyczy zagadnień wynikających z potrzeby obniżenia poziomów emisji podczerwieni do otoczenia przez niektóre rodzaje owców. Nieschładzane gazy spalinowe odpływajace do otoczenia mają znaczący udział w promieniowaniu podczerwonym śmigłowca w locie. Przedmiotem analizy i modelowania jest działanie dobudowanego schładzacza bezprzeponowego, pobierającego samoczynnie powietrze chłodzące otoczenia na zasadzie eżekcji. W wyniku modelowania uzyskuje się podstawy do wstępnego oszacowania parametrów schładzanych spalin, a także wytyczne dla geometrii urządzenia.
    The paper presents a model of interaction of membranneless, ejector exhaust cooler with the helicopter turbine engine in terms of lowering the temperature and changes of CO2 and H2O shares in the air and exhaust gas mixture outflowed to the environment. Scope of work addresses issues arising from the need to reduce the levels of infrared emissions into the environment by certain types of helicopters. Noncooled exhaust gases outflowing into the environment form a significant share of infrared radiation in the helicopter flight. The subject of analysis and modeling is performance of added membranneless cooler, ingesting the cooling air from the environment on ejection principle. In the result of modelling process the preliminary estimates of the cooled exhaust parameters are obtained, as well as guidelines for the geometry of the device.
    Źródło:
    Prace Instytutu Lotnictwa; 2008, 3-4 (194-195); 215-228
    0509-6669
    2300-5408
    Pojawia się w:
    Prace Instytutu Lotnictwa
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Sekularne i ekstremalne procesy erozji wodnej gleb na Pojezierzu Drawskim
    Secular and extreme soil erosion processes in the Drawskie Lakeland
    Autorzy:
    Majewski, Mikołaj
    Powiązania:
    https://bibliotekanauki.pl/articles/295194.pdf
    Data publikacji:
    2020
    Wydawca:
    Stowarzyszenie Geomorfologów Polskich
    Tematy:
    gleba
    erozja wodna
    proces sekularny
    proces ekstremalny
    Pojezierze Drawskie
    warunki meteorologiczne
    rzeźba terenu
    litologia
    temperatura powietrza
    opady atmosferyczne
    klimat
    pokrywa śnieżna
    przemarznięcie gruntu
    soil
    water erosion
    secular process
    extreme process
    Drawskie Lakeland
    meteorological conditions
    relief of the terrain
    lithology
    air temperature
    precipitation
    climate
    ice sheets
    Opis:
    Soil erosion by water is one of the most important factors affecting contemporary landscape changes within the lowland geoecosystems in Central Europe. Soil erosion by water mainly depends on: rainfalls (especially its intensity and erosivity), length of slope and its inclination, type of cultivation and usage of land, anti-erosion treatments and susceptibility of soils to erosion. The aim of conducted research was to evaluate conditioning and magnitude of secular and extreme soil erosion processes in the Drawsko Lakeland with special considering of rainfall erosivity index (EI30). The main goal was realised through several research tasks. The first task involved examination of surface runoff and slope wash conditionings, course and quantity in the testing plot located within the Chwalimski Potok catchment. The second task was related to evaluate rainfall impact to soil erosion by water processes. It was realised by computation rainfall characteristics: intensity, kinetic energy and erosivity. In order to assess secular and extreme soil erosion impact to land relief changes, research were provided with additional details by conducting three field experiments with simulated rainfall. Stationary observation and quantitative researches of soil erosion (at testing plots) have been conducting within the Chwalimski Brook catchment for three hydrological years (2012–2014). The slope with the test area is located within the 1st order catchment being a subsystem of the Młynski Brook catchment and then followed by the upper Parsęta catchment. This area covers 4.8 hectares and is characterised by short slopes with small height variances up to 10 meters. Historically, the area was covered with agricultural crops, currently they cover about 10% of the area. The slope is covered with gleyic retisols and its average inclination is about 4 degrees with its south-east exposure. The measuring system of soil erosion covered 5 testing plots with different agricultural use (bare fallow, meadow, potatoes, spring and winter crops). Plots are 42 metres long and 4 metres width. In the bottom edge of each plot catchers with volume of 800 dm3 were installed. In this research, only data from black fallow were considered. Such tillage is recognised as a standard in soil erosion studies. Two experiments have been conducted in this testing plot. The third one has been conducted on slope located within an area of undulated morainic plateau in the Kłuda catchment. The slope is characterised by greater height variances than in Chwalimski Brook catchment. The slope, where the experiment has been conducted, is situated within local closed depression and is covered by sands underlain by boulder clay. Its average slope is about 10° with its southwest exposure. Although annual precipitation in the three-year measurement period was comparable with mean value from multi-year period (1987–2014), its intensity and erosivity were distinguishably lower. Such rainfall conditions are not favourable for extreme soil erosion by water processes, thus any relief forms from such geomorphological processes were not observed in the Drawsko Lakeland. Due to lack of that kind of forms, in 2013 and 2014, three field experiments were conducted. The main aim of experiments was to evaluate the impact of high intensity rainfall on soil surface. The first experiment consisted of 5, the second and the third of 4 rainfall simulations. The rainfall was created by using a purpose-built rain simulator, consisting of 3 and 6 sprinklers placed around the testing plot. Despite the slope inclination in the Kłuda catchment was 2.5 times steeper than Chwalimski Potok’s slope, surface runoff attained smaller volume, because of remarkably higher infiltration rate. In 2012–2014, surface runoff and soil loss has occurred 8 times each year. The maximal monthly surface runoff volume was registered in February 2012, and it equalled 10.1 dm3 m−2 and the maximal soil loss value was registered in May 2013 and equalled 3,198 kg ha−1. Annual runoff volumes were between 31.2 dm3 m−2 in 2012 and 38.8 dm3 m−2 in 2013, whereas annual soil loss values ranged from 740 kg ha−1 in 2012 to 5,700 kg ha−1 in 2013. Soil erosion values caused by simulated rainfall during field experiments were similar or significantly higher than annual values. Surface runoff was between 31.2 dm3 m−2 in the first experiment and 34.2 dm3 m−2 in the second one, whilst soil loss was between 4,632 kg ha−1 and 8,637 kg ha−1. The achieved experiment results have been compared with soil erosion rate achieved from stationary observations. The results show that runoff and soil loss considerably increase during rainfalls with high amount, intensity and erosivity. Furthermore, individual extreme erosive events may exceed annual (secular) soil erosion processes. Conducted stationary research indicates that annual soil erosion primarily depends on individual rainfall and erosive events, which considerably exceed mean values. In order to evaluate the soil susceptibility to erosion by water in the Drawsko Lakeland, high resolution potential and actual soil erosion risk maps were prepared. The qualitative assessment of soil erosion risk was based on geoinformation technologies. The model considers following conditions affecting the size of soil erosion: slope steepness and aspect, topographic factor LS (unit upslope contributing area), lithology, rainfall erosivity (Modified Fournier Index calculated from monthly and annual precipitation data) and land use and land cover from Corine Land Cover 2006. To prepare the map of potential soil erosion risk, land use from Corine Land Cover was not considered. Thematic maps have been reclassified into a 4-degree division. The results of the soil erosion risk assessment in the Drawsko Lakeland reveal the fact that a majority of its area is characterized by moderate or low erosion risk levels. Areas with high erosion risk are mostly located in the northern part of the Lakeland. The achieved results from stationary observations and field experiments may indicate that the soil loss magnitude significantly increases during rainfall with higher intensity, greater totals and accumulated in time rainfall events. This may confirm the high potential of soil erosion by water processes of above- -average magnitude and intensity in the discharge of material from agricultural used slopes.
    Źródło:
    Landform Analysis; 2020, 39; 1-106
    1429-799X
    Pojawia się w:
    Landform Analysis
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-5 z 5

      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