Wyniki wyszukiwania - BazTech

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Aircraft operators maintenance decisions supporting method

Szrama Sławomir, Gill Adrian

Archives of Transport

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2021

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Vol. 59, iss. 3

93--111

EN

A key element of exploitation processes constitutes maintenance operations and tasks. While being conducted in the proper way, they have a crucial effect on achieving the assumed by aircraft designer and operator goals. Properly conducted maintenance operations allow to meet all the technical objects readiness requirements as well as to achieve desired acceptable risk level. Maintenance system effectiveness might be generally a crucial task for company or entity responsible for the maintenance. In this context, particularly relevant become technical object maintenance procedures and tasks developed by their manufacturers. Experience of the article authors quite early shows the need of the maintenance programmes modification. Aircraft manufacturers usually are not so eager to develop and implement maintenance programme modifications. Presented situation is very much the case in aviation transport. This was the reason why authors of this article decided to prepare and develop this elaboration which might constitute the assistance and supports complex technical objects users in maintenance decision. The main purpose of this article is to present maintenance decisions’ supporting method for the aircraft operators. This article provides guidelines which include a description of risk in the context of aviation maintenance and introduction of some methodologies, tools and criteria that support identification, analysis and evaluation of risk. Authors included idea, how the aircraft preventive maintenance could be used to mitigate aircraft failure risk during flight operations. It also shows how to adopt and develop effective maintenance program using tools for adequate risk analysis, optimal interval assignments, and selection of the most effective maintenance task. Authors presented methodology and described steps of the logic diagram analysis for the aircraft systems and their components, in order to manage and adopt aircraft maintenance program to fulfil aircraft airworthiness requirements and operational availability. The whole methodology was described on the basis of the F 16 aircraft maintenance system and with reference to the maintenance data. This article might also constitute an introduction to the aircraft maintenance programme development method.

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Calibration of precipitation estimation algorithm with particular emphasis on the Pomeranian region using high performance computing

Bieliński T., Chybicki A.

Hydroacoustics

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2016

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Vol. 19

17--26

EN

Fast and accurate precipitation estimation is an important element of remote atmosphere monitoring, as it allows, for example, to correct short-term weather forecasts and the prediction of several types of meteorological threats. The paper presents methodology for calibrating precipitation estimation algorithm based on MSG SEVIRI sensor data, and Optimal Cloud Analysis product available via EumetCast transmission. Calibration is performed in a predefined coastal zone area, and utilizes the parallelized gradient computing method. In order to perform and validate results of estimation, reference weather radar data was provided by the Meteorology and Hydrology Research Institute (pol. Instytut Meteorologii i Gospodarki Wodnej - IMGW). The research was conducted using the Tryton supercomputer - the high performance computing environment of Gdansk University of Technology.

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Mesoscale Convective Systems monitoring on the basis of MSG data - case studies

Szafranek K., Jakubiak B., Lech R., Tomczuk M.

Artificial Satellites : Journal of Planetary Geodesy

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2015

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Vol. 50, No. 2

91--103

EN

Analysis described in the paper were made in the frame of the PROZA (Operational decisionmaking based on atmospheric conditions, http://projekt-proza.pl/) project co-financed by the European Union through the European Regional Development Fund. One of its tasks was to develop an operational forecast system, which is going to support different economies branches like forestry or fruit farming by reducing the risk of economic decisions with taking into consideration weather conditions. The main purpose of the paper is to describe the method of the MCSs (Mesoscale Convective Systems) tracking on the basis of the MSG (Meteosat Second Generation) data. Until now several tests were performed. The Meteosat satellite images in selected spectral channels collected for Central Europe Region for May 2010 were used to detect and track cloud systems recognized as MCSs in Poland. The ISIS tracking method was applied here. First the cloud objects are defined using the temperature threshold and next the selected cells are tracked using principle of overlapping position on consecutive images. The main benefit of using a temperature threshold to define cells is its efficiency. During the tracking process the algorithm links the cells of the image at time t to the one of the following image at time t+dt that correspond to the same cloud system. Selected cases present phenomena, which appeared at the territory of Poland. They were compared to the weather radar data and UKMO UM (United Kingdom MetOffice Unified Model) forecasts. The paper presents analysis of exemplary MCSs in the context of near realtime prediction system development and proves that developed tool can be helpful in MCSs monitoring.

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Zastosowanie informacji satelitarnej MSG/SEVIRI do oceny zachmurzenia ogólnego w Polsce

Dębek M.

Teledetekcja Środowiska

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2011

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T. 45

9--16

EN

Meteosat Second Generation is a geostationary satellite, designed to explore atmospherical processes. Main instrument on board MSG is SEVIRI, a 12-channel scanning radiometer, observing the Earth full disk in nominal MSG position at 0° longitude with a horizontal resolution of 3 km at nadir. In this paper one of MSG Cloud Products – Cloud Mask (CMa) was used to analyze cloud detection over Poland. The main objective of Cloud Mask is to discriminate all cloudfree pixels, because correct cloud detection is an important pre-processing step, to use many different MSG products. As the result of this algorithm all pixels are categorized in five categories as cloudy, cloud contaminated, cloud-free, snow/ ice fi lled or no processing. The aim of this study is to compare Cloud Mask data to a standard synoptical observations. Ground observations classified cloudiness in a 9-degree scale (octas) and normalization this different scales was the greatest methodical problem. Base sources was 12 situations cloud cover, represented varied types of cloudiness over Poland, in effect 812 sat-synop observations. This satellite data was compared with ground observations through contingency tables and statistical indicators. The percentage of correct observations for 5x5 pixel matrix equals 27,3. As the results shows, it is visible linear relationship between satellite and synop data with correlation coefficient equals 0.73. Most important effect of this study is to indicate a underestimating satellitebased cloudiness observations. The mean error (satellite-synop) ranging between +0,6 and –1,3 octas, and except cloud free situations, is negative.

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Frame distortion estimation and its application to extraction priority assignment for MGS of H.264/SVC

Zhu T., Zhang X.-wei

Przegląd Elektrotechniczny

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2011

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R. 87, nr 1

284-289

EN

Based on research of frame distortion estimation, an extraction priority assignment method is proposed for the MGS bit-stream. Firstly, extraction priority is derived from rate distortion optimization method. Then, frame distortion estimation is performed from estimation of coefficients dropping distortion and drift distortion. At last, depending on quality layer concept, extraction priorities are assigned efficiently. Experimental results show that the proposed method outperforms the priority assignment method and bit-stream extraction of H.264/SVC.

PL

Zaproponowano metodę ekstrakcji pierwszeństwa dla MGS bit-stream bazującą na określaniu zakłócenia ramki. Najpierw ekstrakcja pierwszeństwa jest wyprowadzona z metody optymalizacji zniekształcenia szybkości. Następnie określa się zniekształcenie ramki ze współczynników zniekształceń kroplowych i zniekształceń zera. Wreszcie zależnie od koncepcji pasm pierwszeństwo jest określane ostatecznie. Rezultaty eksperymentu wykazały, że proponowana metoda może być zastosowana do określania pierwszeństwa i ekstrakcji strumienia bitów w H.264/SVC.