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EN
This article discusses the use of wavelet decomposition in the diagnostics of vibrometric signals of an engine. Apart from presenting the possibility of using wavelets in diagnostics, the authors take up the subject of the applicability range of processing for stationary signals, which until now has been reserved for non-stationary signals. A unified definition of signal stationarity has been proposed, which is not based on statistics. The authors presented methods of wavelet decomposition of a vibrometric signal of combustion engine vibrations, measured with the use of LDV (Laser Doppler Vibrometry). Laser measurements allows for studying an object without 'touching' its housing. Basing on the relative velocity of engine vibrations, the authors indicate how reliable vibrations are in diagnostics. Despite higher costs, this measurement method gives better results (for specific cases) than acoustic studies. Transform – wavelet decomposition is a solution hardly ever used in machine diagnostics; it is more often applied in medicine and image recognition. The authors presented the differences that can be obtained for different levels of decomposition, and also presented the impact on the engine condition assessment through the use of filtering (windowing) the signal before decomposition.
2
Content available The effect of fuel mixture on engine vibrations
EN
In the article, the authors analyze the effect of a fuel mixture (iso-octane, butanol and ethanol) on the generation of engine vibrations. The paper presents the results in the form of frequency response (using the Fast Fourier Transform - FFT) for three mixtures of different proportions. The measurements were made with the use of accelerometers and data acquisition cards, conditioning the received signal. The vibration component, in the form of acceleration, will be subjected to a FFT and presented in graphical form (periodogram). The authors put a special emphasis on a comparative analysis, indicating changes in harmonics, which may be a potential cause of engine degradation.
EN
This paper presents a study of vibrations appearing in a vehicle in the process of its operation. The authors describe the primary source of the vibrations and their propagation in the entire structure. The observations were performed on the passenger cars with various gasoline and diesel engines. The aim was to examine the level of damping factor in the different locations in the car, precisely specified for the purpose of this studies. The secondary goal was to develop an effective method of obtaining and analyzing signals generated during the engine operation. The chosen instrument was Laser Doppler Vibrometer (LDV), which is used as the non-intrusive measurement utensil to detect velocity variations in designated places. The signals are gathered and collected as group of sinusoidal characteristics in the time domain. In order to achieve specific information about every component of the original signal, the authors apply Fast Fourier Transform (FFT) as the analyzing method. It allows to distinct the basic sinusoidal characteristics in the frequency domain through the spectral analysis. Based on the results, the authors are able to distinguish the dominant modes from the complex signal and indicate their impact on the car.
EN
Soil magnetometry, based on topsoil magnetic susceptibility measurement, has been proven in the literature to be very useful and increasingly applicable screening technique of soils affected by anthropogenic pressure. According to the literature data, this method requires further improvement, especially in the field of magnetometric imaging techniques. The aim of the study was assessment of magnetic transformations of soils in the city of Opole (Opolskie Voivodeship) using soil magnetometry and three magnetometric data interpolation techniques (natural neighbour NN, inverse distance weightening IDW and ordinary kriging OK). The data was collected during field measurements of magnetic susceptibility, carried out in an area of 7.1 km2, in a network of 124 measurement points, in the year 2015. The location of the points was determined using the Garmin GPS GPSMap 64st device, and the magnetometric measurements were performed in situ using the MS2 meter and the MS2D sensor from Bartington Instruments. The research showed high values of magnetic susceptibility and occurrence of soil magnetic anomalies in the study area. This was accompanied by geochemical transformations of soils, revealed in previous research. The results suggest that it could be caused by the long-term deposition of cement dusts, emitted in increased quantities in former times by the cement plant, which has left its footprint in the environment. When analyzing the usefulness of the magnetometric data interpolation techniques, the IDW technique best reflected the spatial distribution of magnetic susceptibility in the study area, while the technique of OK, due to the so-called smoothing effect, turned out to be less useful.
PL
Magnetometria glebowa, polegająca na pomiarze podatności magnetycznej wierzchniej warstwy gleby, jest bardzo przydatną i coraz powszechniej stosowaną techniką monitorowania stanu gleb objętych wpływem antropopresji. Jak wynika z danych literaturowych, metoda ta wymaga dalszego udoskonalania, szczególnie w zakresie technik obrazowania danych magnetometrycznych. Celem badań była ocena przekształceń magnetycznych gleb na terenie miasta Opola (woj. opolskie) z zastosowaniem magnetometrii glebowej oraz trzech technik interpolacji danych magnetometrycznych (naturalnego sąsiedztwa NN, ważonych odwrotnych odległości IDW oraz krigingu zwykłego OK). Dane zostały zgromadzone podczas pomiarów terenowych podatności magnetycznej, wykonanych na powierzchni 7,1 km2, w sieci 124 punktów pomiarowych, w 2015 r. Lokalizacje punktów określono za pomocą urządzenia Garmin GPS GPSMap 64st, a pomiary magnetometryczne wykonano in situ za pomocą miernika MS2 i czujnika MS2D firmy Bartington Instruments. Badania wykazały wysokie wartości podatności magnetycznej oraz występowanie glebowych anomalii magnetycznych na badanym terenie. Towarzyszą temu przekształcenia geochemiczne gleb, wykazane we wcześniejszych badaniach. Wyniki sugerują, że przyczyną tego stanu mogła być długoletnia depozycja pyłów cementowych, emitowanych w latach ubiegłych w zwiększonej ilości przez cementownię, która pozostawiła swój ślad w środowisku. Analizując przydatność zastosowanych technik interpolacji danych magnetometrycznych, technika IDW najlepiej odzwierciedlała rozkład przestrzenny podatności magnetycznej na badanym terenie, podczas gdy technika OK, z powodu tzw. efektu wygładzającego, okazała się mniej przydatna.
PL
Przeanalizowano zmiany struktury przestrzennej 5 wsi leżących w dolinie Odry, w województwie opolskim – Landzmierz, Kobylice, Zimnice Małe, Stobrawa, Szydłowice. Badania wykazują, iż na przestrzeni minionego wieku struktura przestrzenna, układ oraz wielkość wsi uległy pewnym zmianom. Nie są to jednak duże zmiany, wpływające na istotne przekształcenie krajobrazu tych obszarów i zmianę ich charakteru. W ostatnim czasie nie rozwija się tam nowa zabudowa, a istniejąca pochodzi z przełomu XIX i XX w. oraz początku XX w. Dzieje się tak mimo tego, że obszary te bardzo często mają wysokie walory przyrodnicze, sprzyjające funkcjom wypoczynkowym, rekreacyjnym a zatem mogłyby się tam rozwijać różne typy zabudowy.
EN
River valleys are very important component of landscape. They have huge meaning in his structure and function, as well as in preservation of living resources. River valleys are also most valuable and universal ecological corridors. Rural landscape in river valleys was shaped by many factors over years. However, in present moment one of the main factors effecting rural landscape in river valley, beside socio-conomic aspects, is factor related with. Villages chosen to research are exposed on seasonally flooding. They have touched in a great extent by flood in 1997. The basic research objective was determination if and in what degree this factor effects rural landscape conversions and evolution and what is the Oder river influence on forming and development of village. The other research objective was determination of potential farthest capability of rural landscape transformation in the Oder river valley. Analysis of chosen village indicate some changes in their spatial structure. There were not important change in spatial system, however has followed buildings concentration and density. Bigger changes appear on village in suburban zone, what indicate that socio-economic factors have significant influence on village development, exceeding even flood hazard aspects. Location in Oder river valley area is a factor braking intensive development and transformation of landscape.
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