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Wyszukujesz frazę "temperature factor" wg kryterium: Temat


Tytuł:
Analiza statystyczna wplywu czynnikow meteorologicznych i glebowych na wartosc temperatury radiacyjnej powierzchni roslin
The statistical analysis of meteorological and soil parameters impact on plant cover radiation temperature
Autorzy:
Mazurek, W
Walczak, R.T.
Baranowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/1401778.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
rosliny
powierzchnia roslin
temperatura radiacyjna
czynniki meteorologiczne
czynniki glebowe
woda glebowa
stres wodny
analiza statystyczna
regresja wielokrotna
plant
plant surface
radiation temperature
meteorological factor
soil factor
soil water
water stress
statistical analysis
multiple regression
Opis:
W pracy dokonano analizy statystycznej metodą regresji wielokrotnej wpływu czynników meteorologicznych i glebowych na wartości temperatury radiacyjnej pokrywy roślinnej. Stwierdzono, iż wprowadzenie do modelu regresji wielokrotnej potencjału wody glebowej jako zmiennej niezależnej poprawia dokładność predykcyjną modelu w przypadku, gdy zmienną zależną jest różnica temperatury pokrywy roślinnej w sytuacji stresu wodnego i przy nieograniczonej dostępności wody glebowej. Przedstawiono zależność temperatury powierzchni roślin od temperatury powietrza, prędkości wiatru, radiacji słonecznej i potencjału wody glebowej.
In this study the statistical analysis was performed, using the multiple regression, of the impact of meteorological and soil parameters on radiation temperature of plant cover. It was stated that including into the model soil water potential as an independent variable of multiple regression, improves its predictive precision in case when the dependent variable is the difference of crop temperature in the conditions of water stress and under unlimited availability of soil water. The relation between crop temperature and air temperature, wind speed, solar radiation and soil water potential is presented.
Źródło:
Acta Agrophysica; 2000, 38; 157-164
1234-4125
Pojawia się w:
Acta Agrophysica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Association between incidence of Lyme disease and spring-early summer season temperature changes in Hungary - 1998-2010
Autorzy:
Trajer, A.
Bobvos, J.
Paldy, A.
Krisztalovics, K.
Powiązania:
https://bibliotekanauki.pl/articles/50739.pdf
Data publikacji:
2013
Wydawca:
Instytut Medycyny Wsi
Tematy:
association
Lyme disease
spring-early summer season
temperature change
Hungary
1998–2010 period
climate change
indicator species
host animal
environmental factor
Opis:
The increase of Lyme borreliosis (LB) can be expected due to climate change, while the distribution of the disease and annual activity of the vector and host animals depend on several factors of the environment. The presented study aimed to assess expressly the spring season temperature dependence on the incidence of LB in Hungary. The weekly LB data were obtained from the National Epidemiologic and Surveillance System for a period of 13 years – 1998–2010. Daily temperature data were derived from the European Climate Assessment and Dataset. The association was studied at national level, descriptive statistics and linear regression models were applied. A significant increasing trend was observed in the mean temperature of the analysed years (0.052 °C per year). The annual LB incidence doubled during the 13 year period. The incidence rates of the periods 1998–2001 and 2007–2010 were 11.1 resp. 17.0 per 100,000. The start of a steep increase in weekly LB incidence (0.1 per 100,000) shifted significantly by 3 weeks earlier, the start date of spring showed similar trend (p=0.0041). LB incidence increased more steadily in spring than in summer, with 79% of the increase being reported during weeks 15–28, with maximum rates of increase occurring in weeks 23–25. The trend was significant between the weeks 15–28. In the warmer years with 19.02 °C mean temperature in May and June, the LB incidence curve reached the annual peak 2–3 weeks earlier, and the descending phase of the curve started earlier than in the colder years with 17.06 °C of the same period.
Źródło:
Annals of Agricultural and Environmental Medicine; 2013, 20, 2
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Benthic Crustacea and Mollusca distribution in Arctic fjord - case study of patterns in Hornsund, Svalbard
Autorzy:
Drewnik, A.
Weslawski, J.M.
Wlodarska-Kowalczuk, M.
Powiązania:
https://bibliotekanauki.pl/articles/48672.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
species distribution
benthos
Mollusca
Crustacea
distribution
Arctic fjord
environmental factor
benthic species
bottom water
water temperature
Hornsund Region
Svalbard
Opis:
We present the results of species distribution modeling conducted on macrobenthic occurrence data collected between 2002 and 2014 in Arctic fjord – Hornsund. We focus on species from Mollusca and Crustacea taxa. This study investigates the importance of individual environmental factors for benthic species distribution, with a special emphasis on bottom water temperature. It aims to verify the hypothesis that the distribution of species is controlled by low water temperatures in the fjord and that the inner basins of the fjord serve as potential refugia for Arctic species threatened by the climate change-related intensification of warmer water inflows. Our results confirm the importance of bottom water temperature in regulating the presence of benthic fauna in the Hornsund fjord. The distribution of studied species is clearly related to specific water mass – colder (<1°C) or warmer (>1°C); and the preferred temperature regimes seem to be species specific and unrelated to analyzed groups. This study supports the notion that inner basins of the Hornsund fjord are potential refugia for cold water Arctic fauna, while the outer and central basins provide suitable habitats for fauna that prefer warmer waters.
Źródło:
Oceanologia; 2017, 59, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of bacterial production in the water column between two Arctic fjords, Hornsund and Kongsfjorden (West Spitsbergen)
Autorzy:
Ameryk, A.
Jankowska, K.M.
Kalinowska, A.
Weslawski, J.M.
Powiązania:
https://bibliotekanauki.pl/articles/47914.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
bacterial production
environmental factor
water column
chlorophyll a
water temperature
bacterial biomass
dissolved organic carbon
dissolved organic matter
Arctic fjord
Spitsbergen
Kongsfjorden
Hornsund
Opis:
Bacterial production and the accompanying environmental factors were measured in the water columns of two Arctic fjords during the cruise in July and August 2013. Water samples were collected at six stations located in the central part of Hornsund and Kongsfjorden. In Hornsund, where average water temperatures were 1.25-fold lower than in Kongsfjorden, the bacterial production was twice as high (0.116 ± 0.102 vs 0.05 ± 0.03 mg C m−3 h−1). Statistical analysis indicated that chlorophyll a concentration itself was not a significant factor that affected bacterial production, in contrast to its decomposition product, pheophytin, originating from senescent algal cells or herbivorous activity of zooplankton. Single and multiple regression analysis revealed that water temperature, dissolved organic carbon (DOC), and pheophytin concentration were the main factors affecting bacterial production in both fjords.
Źródło:
Oceanologia; 2017, 59, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Contrasting zooplankton communities (Arctic vs. Atlantic) in the European Arctic Marginal Ice Zone
Autorzy:
Blachowiak-Samolyk, K.
Powiązania:
https://bibliotekanauki.pl/articles/47495.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
zooplankton community
Arctic water
Fram Strait
temperature
Barents Sea
Atlantic water
salinity
environmental factor
Opis:
Relationships between the zooplankton community andv arious environmental factors (salinity, temperature, sampling depth and bottom depth) were established in the European Arctic Marginal Ice Zone (MIZ) using multivariate statistics. Three main zooplankton communities were identified: an Atlantic Shallow Community (AtSC), an Arctic Shallow Community (ArSC) anda Deep Water Community (DWC). All species belonging to AtSC andArSC were pooledandtheir relative abundances in the total zooplankton calculated with respect to a particular layer (surface, midan dd eep strata), regions (the Barents Sea, Fram Strait andt he waters off northern Svalbard), years (1999 or 2003) and seasons (spring or autumn). Mapping of the proportions of Arctic andA tlantic species ledto the conclusion that zooplankton from the MIZs do not exactly follow complementary water masses, although the general pattern of AtSC and ArSC dominance accords with the physical oceanography of the study area (AtW and ArW respectively). The mid layer proved to be a better predictor of mesozooplankton distribution than the unstable conditions near the surface.
Źródło:
Oceanologia; 2008, 50, 3; 363-389
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Deforestation and its impacts on climate change an overview of Pakistan
Autorzy:
Ali, A.
Riaz, S.
Iqbal, S.
Powiązania:
https://bibliotekanauki.pl/articles/11968.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
climate change
deforestation
Pakistan
catastrophic event
forest age
natural factor
weather
industrialization
urbanization
global temperature
surface temperature
disaster
South Asia
Opis:
Forests are one the main natural factors that regulate and determine climate, weather patterns and amount of CO2 of an area. With rapid industrialization and rapid urbanization there is a significant increase in deforestation and as a consequence rise in global mean surface temperatures. Rapid and unchecked cut down of forest cover has resulted in some of the worst disasters during the last decades. This paper focuses on studying the role of deforestation, its influence on climate change phenomena and its consequences in Pakistan.
Źródło:
Papers on Global Change; 2014, 21
2300-8121
1730-802X
Pojawia się w:
Papers on Global Change
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dependence of the photosynthesis quantum yield in oceans on environmental factors
Autorzy:
Wozniak, B.
Dera, J.
Ficek, D.
Ostrowska, M.
Majchrowski, R.
Powiązania:
https://bibliotekanauki.pl/articles/48279.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
primary production
water temperature
quantum yield
environmental factor
bio-optical modelling
nutrient content
phytoplankton
chlorophyll
irradiance
photosynthesis
Opis:
Statistical relationships between the quantum yield of photosynthesis and selected environmental factors in the ocean have been studied. The underwater irradiance, nutrient content, water temperature and water trophicity (i.e. the surface concentration of chlorophyll Ca(0)) have been considered, utilizing a large empirical data base. On the basis of these relationships, a mathematical model of the quantum yield was worked out in which the quantum yield Φ is expressed as a product of the theoretical maximum quantum yield ΦMAX = 0.125 atomC quanta−1 and six dimensionless factors. Each of these factors fi appears to be, to a sufficiently good approximation, dependent on one or two environmental factors and optical depth at most. The model makes it possible to determine the quantum yield from known values of these environmental factors. Empirical verification of the model yielded a positive result – the statistical error of the approximate values of the quantum yield Φ is 42%.
Źródło:
Oceanologia; 2002, 44, 4
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Distribution and role of the genus Oithona (Copepoda: Cyclopoida) in the South China Sea
Autorzy:
Wang, L.
Du, F.
Wang, X.
Li, Y.
Ning, J.
Powiązania:
https://bibliotekanauki.pl/articles/47786.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
Oithona
Copepoda
Cyclopoida
temperature
hydrological factor
phytoplankton
ichthyoplankton
South China Sea
Oithona plumifera
Oithona similis
Opis:
The relationships between the small cyclopoid copepod Oithona and hydrological factors, phytoplankton and ichthyoplankton were evaluated using the data obtained in the central South China Sea (SCS) in summer 2014. The genus abundance ranged from 6.00 ind. m3 to 93.75 ind. m3 with high abundance band occurring in the branch of SCS Monsoon Jet. The lower temperature and higher salinity in the surface water of the band than other zones indicated that deep water intrusion was a positive factor for aggregation of the genus. The community structure of the genus was dominated by Oithona plumifera and Oithona similis made up 97% of the genus abundance associated with Oithona tenuis. The result of db-RDA analysis showed that the community structure of the genus was affected by temperature, Chl a, larval fishes and fish spawns, and temperature was the most important limiting factor. The result of GAMs analysis showed that abundance of O. tenuis, and copepodites were affected by Chl a, larval fishes and fish spawns; abundance of O. similis was affected by Chl a and fish spawns; and abundance of O. plumifera was affected by Chl a and larval fishes. Therefore, we suggest that the branch of SCS Monsoon Jet and deep water intrusion favor aggregation of plankton in the central SCS in summer. We confirm that the temperature is the limiting factor to the reproduction of the genus Oithona in tropic seas and the genus Oithona is a food-web linker between primary production and larval fishes in the central SCS.
Źródło:
Oceanologia; 2017, 59, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of meteorological factors on the radial growth of pine latewood in northern taiga
Autorzy:
Neverov, N.
Chistova, Z.
Mineev, A.
Powiązania:
https://bibliotekanauki.pl/articles/2106664.pdf
Data publikacji:
2022
Wydawca:
Instytut Badawczy Leśnictwa
Tematy:
late wood
pine
meteorological factor
air temperature
wind speed
taiga
Opis:
The purpose of this study is to evaluate the influence of day and night meteorological parameters (air temperatures and dew points, relative humidity, wind speed and precipitation) on the radial growth of pine latewood in northern taiga, in typical conditions of its growth. The study was conducted in the north of the Arkhangelsk region (Russia). A total of 63 cores were selected from seven most representative sites. Meteorological parameters were obtained from the WMR 918 H digital weather station (Huger GmbH, Germany), located directly on the study area and operating in monitoring mode. The analysis used meteorological data for the period 2008–2015. Correlation with night and day air temperature in June and July (0.72–0.77) was revealed in blueberry type. In all the stands studied, a reliable correlation with wind speed was established, direct (0.77‒0.88) and inverse (−0.7 to −0.99), but each sample plot had an individual dependence. A reliable correlation with the humidity of August and September (0.64–0.87) and an inverse correlation with precipitation in May and August (−0.63 to −0.75) were established. In general, pine in blueberry, cowberry and pine on swamp types have a similar reaction to the variability of meteorological factors, the most important of which is the temperature regime of air and wind speed.
Źródło:
Folia Forestalia Polonica. Series A . Forestry; 2022, 64, 1; 7-14
0071-6677
Pojawia się w:
Folia Forestalia Polonica. Series A . Forestry
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth responses of Picea abies to climate in the central part of the Ceskomoravska Upland (Czech Republic)
Autorzy:
Rybnicek, M.
Cermak, P.
Zid, T.
Kolar, T.
Powiązania:
https://bibliotekanauki.pl/articles/41537.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Dendrologii PAN
Tematy:
growth response
Picea abies
Norway spruce
precipitation
temperature
climate
environmental factor
tree ring
biomass
Ceskomoravska Upland
Czech Republic
Opis:
The aims of the study were to determine the effect of temperatures and precipitation on the ring width and to compare the results with the results of previous studies conducted in other mountain ranges of the Czech Republic. The research was performed in the central part of the Ceskomoravská Upland in the vicinity of Herálec municipality in selected 70- up to 110-year-old spruce stands at altitudes from 680ma.s.l. to 779 m a.s.l. Measuring of tree-ring widths and synchronization of individual ring series were conducted in PAST4. The age trend was removed by ARSTAN and climatic effects were modelled in DendroClim2002. The correlation of tree-ring width with monthly precipitation is positive and statistically significant for July of the previous year and for the entire summer period from June to September of the current year. The correlation of tree-ring width with mean monthly temperatures is negative and statistically significant for July and September and positive and statistically significant for October of the previous year. Negative correlation was also found for temperatures of the entire summer period from June to September of the previous year. The regional tree-ring chronology mainly shows two periods of highly reduced increment: from 1992 to 1996 and from 2003 to the end of the analysed period. The results thus confirm the hypothesis that the tree-ring width is in positive correlation with summer precipitation and negative correlation with summer temperatures. Also the results of the habitual diagnostics have shown a relatively low degree of crown transformation which indicates a weak or short-term stress load.
Źródło:
Dendrobiology; 2012, 68
1641-1307
Pojawia się w:
Dendrobiology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Implementation of improved application for determining gas Z-factor of gas from the Molve field
Zastosowanie poprawek do obliczania współczynnika Z dla gazu na przykładzie złoża Molve
Autorzy:
Juttner, I.
Vulin, D.
Lazo, A.
Powiązania:
https://bibliotekanauki.pl/articles/300287.pdf
Data publikacji:
2008
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
współczynnik Z
równanie stanu
pseudokrytyczne wartości temperatury i ciśnienia
Z-factor
equation of state
pseudocritical pressure and temperature
Opis:
Separator gas composition and separator liquid composition and corresponding standard data (pressure, temperature, liquid density, specific gravity etc.) were measured to obtain recombined fluid composition. The results of separator gas test and recombined wellstream were grouped and observed separately to verify published methods of compressibility correction factor, Z prediction. It was found that Dranchouk-Abu-Kassem method is in good correlation with laboratory data. Critical properties of separator gas and wellstream fluid mixtures, and also C7+ fractions were correlated using a number of published correlations. The properties were found to be similar to that found in literature, characterized by an accuracy decrease with decreasing molar weight accuracy of plus the fractions. However, individual pressure vs. Z-factor curves for each observed laboratory fluid analysis, calculated using the correlations, showed acceptable match with measured and then calculated pressure versus Z data. Modified correlation was made, similar to Sutton's and Standing's correlations for calculating pseudocritical temperature and pressure as function of specific gravity and compared to published correlations.
W pracy dokonano pomiaru skład gazu i płynu w separatorze oraz standardowe dane dotyczące ciśnienia, temperatury, gęstości cieczy, ciężaru właściwego w celu ustalenia nowego składu płynu. Zestawiono wyniki badania składu gazu z separatora i nowy skład strumienia, a następnie zweryfikowano opublikowane metody korekcji współczynnika ściśliwości Z. Wykazano korelację metody Dranchouk-Abu-Kassem z danymi laboratoryjnymi. Wykorzystując znane z literatury metody, skorelowano krytyczne właściwości gazu z separatora, mieszaniny płynu w otworze oraz cząstki C7+. Otrzymane właściwości były podobne do przedstawionych w literaturze i charakteryzowały się spadkiem dokładności wraz ze spadkiem dokładności ciężaru molowego cząstek dodatnich. Z analizy krzywej funkcji ciśnienia i współczynnika Z dla każdego z płynów badanych na podstawie korelacji wynika, że uzyskano akceptowalną zgodność z danymi pomiarowymi i następnie obliczono funkcję ciśnienia i współczynnika Z. Zmodyfikowano korelację, analogicznie do korelacji Suttona i Standinga na pseudokrytyczne wartości temperatury i ciśnienia jako funkcji ciężaru właściwego, a następnie porównano i przestawiono otrzymane korelacje.
Źródło:
Wiertnictwo, Nafta, Gaz; 2008, 25, 2; 323-330
1507-0042
Pojawia się w:
Wiertnictwo, Nafta, Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of environmental factors on reproduction of polar vascular plants
Autorzy:
Kellmann-Sopyla, W.
Pastorczyk, M.
Gielwanowska, I.
Powiązania:
https://bibliotekanauki.pl/articles/11942.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
environmental factor
plant reproduction
polar plant
vascular plant
climate change
generative reproduction
warming
flower development
seed formation
air temperature
ultraviolet radiation
reproductive phase
vegetation
Opis:
In the last few decades, changes of reproductive pattern of polar vascular plants have been observed, for the benefit of generative propagation. The reasons for this phenomenon are attributed to intensively following climate change, whose effects may be various. Warming causes the production of the greater number of generative structures, with higher quality. Our macroscopic observations conducted on specimens of polar vascular plants, cultivated in University of Warmia and Mazury greenhouse, indicate that the effect of temperature increase on flower development and seed formation is inconsistent. On the other hand enhanced levels of UV-B radiation can negatively affect seedlings. The complexity of the climate change causes tremendous difficulties in defining a clear and unquestioned way of modifications during the reproductive phase of the described plants.
Źródło:
Papers on Global Change; 2011, 18
2300-8121
1730-802X
Pojawia się w:
Papers on Global Change
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of selected abiotic factors on the decomposition of chlorophylls
Autorzy:
Kowalewska, G.
Szymczak, M.
Powiązania:
https://bibliotekanauki.pl/articles/48301.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
chlorophyll
temperature
abiotic factor
blue-green alga
Anabaena variabilis
beta-carotene
decomposition
Opis:
The paper presents the results of experiments to determine the influence of selected physico-chemical factors – oxygen, visible light and temperature – on the decomposition of (1) chlorophylls a, b and c, chlorophyll a derivatives and β-carotene in acetone solution, and (2) chlorophyll a and β-carotene in axenic cultures of the blue-green algae Anabaena variabilis. The results indicate that both in acetone extracts and in blue-green algae cultures these pigments were most sensitive to light and oxygen; temperatures of up to 25◦C had no marked influence on these compounds. Under anoxia in acetone solution, the stability towards light decreased in the order chlorophyll a, chlorophyll b, chlorophylls c. Chlorophyll a, moreover, was less stable than its derivatives – phaeophorbides, phaeophytins, pyrophaeophytins and steryl chlorins – but more stable than β-carotene, in the last case also in the blue-green algae cultures. Decomposition of all the pigments proceeded mainly via the breakdown of the porphyrin macrocycle, since the decomposition products were not detected in the VIS range. On the basis of these experiments one can state that while light and oxygen may have a decisive direct influence on the distribution of chlorophylls and β-carotene in sediments, in the natural environment, temperatures of up to 25◦ C may have very little immediate effect.
Źródło:
Oceanologia; 2001, 43, 3; 315-328
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Lifetime prediction method for MEMS gyroscope based on accelerated degradation test and acceleration factor model
Metoda prognozowania czasu pracy żyroskopu MEMS na podstawie testu przyspieszonej degradacji i modelu współczynnika przyspieszenia
Autorzy:
Liu, Yao
Wang, Yashun
Fan, Zhengwei
Hou, Zhanqiang
Zhang, Shufeng
Chen, Xun
Powiązania:
https://bibliotekanauki.pl/articles/301995.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
MEMS gyroscope
temperature stress
accelerated degradation test
acceleration factor model
Allan variance
żyroskop MEMS
naprężenie cieplne
test przyspieszonej degradacji
model współczynnika przyspieszenia
wariancja Allana
Opis:
The reliability analysis of MEMS gyroscope under long-term operating condition has become an urgent requirement with the enlargement of its application scope and the requirement of good durability. In this study we propose a lifetime prediction method for MEMS gyroscope based on accelerated degradation tests (ADTs) and acceleration factor model. Firstly, the degradation characteristic (bias instability) is extracted based on Allan variance. The effect of temperature stress on the degradation rate of bias instability is analyzed, and it shows that the degradation rate of bias instability would increase with the increase of the temperature. Secondly, the ADTs of MEMS gyroscope are designed and conducted, the degradation model of MEMS gyroscope is established based on the output voltage of MEMS gyroscope and Allan variance. Finally, the acceleration factor model of MEMS gyroscope under temperature stress is derived, and the lifetime of the MEMS gyroscope is predicted based on two group tests data under high stress level. The results show that the lifetime calculated by the acceleration factor model and mean lifetime under high stress levels is close to the mean lifetime calculated by the linear equation at normal temperature stress.
Analiza niezawodności żyroskopu MEMS w warunkach długotrwałej pracy stała się pilną koniecznością wraz z rozszerzeniem zakresu jego zastosowania i wprowadzeniem wymogu dobrej trwałości. W niniejszym artykule, zaproponowano metodę prognozowania czasu pracy żyroskopu MEMS w oparciu o testy przyspieszonej degradacji i model współczynnika przyspieszenia. W pierwszej kolejności, wyznaczono charakterystykę degradacji (niestabilność wskazań) na podstawie wariancji Allana. Analizowano wpływ naprężenia cieplnego na szybkość degradacji w zakresie niestabilności wskazań. Analiza wykazała, że szybkość degradacji wzrastała wraz ze wzrostem temperatury. Następnie, opracowano i przeprowadzono testy przyspieszonej degradacji żyroskopu MEMS, a model jego degradacji ustalono na podstawie napięcia wyjściowego żyroskopu i wariancji Allana. Na koniec, wyprowadzono model współczynnika przyspieszenia dla żyroskopu MEMS w warunkach naprężenia cieplnego, a żywotność żyroskopu prognozowano na podstawie danych z dwóch testów grupowych przeprowadzonych w warunkach wysokiego naprężenia. Wyniki pokazują, że czas pracy obliczony na podstawie modelu współczynnika przyspieszenia i średni czas pracy przy wysokich poziomach naprężeń są zbliżone do średniego czasu pracy obliczonego na podstawie równania liniowego przy normalnym naprężeniu cieplnym.
Źródło:
Eksploatacja i Niezawodność; 2020, 22, 2; 221-231
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Low temperature seed germination of cucumber: genetic basis of the tolerance trait
Autorzy:
Klosinska, U.
Kozik, E.U.
Nowicki, M.
Wehner, T.C.
Powiązania:
https://bibliotekanauki.pl/articles/1842.pdf
Data publikacji:
2013
Wydawca:
Instytut Ogrodnictwa
Tematy:
cucumber
Cucumis sativus
seed germination
low temperature
chilling
inheritance
genetic factor
cold tolerance
Źródło:
Journal of Horticultural Research; 2013, 21, 2
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł

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