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1
PL
Drewniane budynki wysokie towarzyszą ludziom od wieków. Współczesny rozwój technologii materiałowej, narzędzi do projektowania i wysoki stopień prefabrykacji pozwolił na budowanie wysokich budynków w stosunkowo niedługim czasie. Mając na uwadze te aspekty oraz proekologiczne względy stosowania konstrukcji drewnianych, można je idealnie wpasować w aktualne wymagania stawiane budownictwu. Przekłada się to na odnotowywany w ostatnich latach wzrost popularności konstrukcji drewnianych. Do pełnego rozwoju tego postępowego trendu potrzeba jeszcze dużo pracy w zakresie dopracowania m.in. kwestii pożarowych czy rozwiązań w zakresie wpływów oddziaływań sejsmicznych, które dają badaczom pole do dalszych działań.
EN
Wooden tall buildings have accompanied people for centuries. Modern development of material technology, design tools and a high degree of prefabrication allowed the construction of tall buildings in a relatively short time. Taking these aspects into account, as well as the pro-ecological considerations of using wooden structures, they can be perfectly fitted into the current requirements for construction. Due to this, there has been an increase in the popularity of wooden structures in recent years. A lot of work is still needed to fully develop this progressive trend, including: fire issues or solutions to the impact of seismic impacts, which provide researchers with scope for further activities.
EN
Electric vehicles (EVs) are increasingly being used, as they are more environmentally friendly than conventional vehicles with internal combustion engines (ICE). Battery electric vehicles (BEVs) can be said to have zero exhaust emissions only if the electricity used to drive these vehicles is obtained in an environmentally friendly way. It is common knowledge that BEVs have a significantly higher overall mass than conventional vehicles. The significantly higher total vehicle weight of BEVs can have various adverse effects on energy consumption during movement and the vehicle's dynamics. In contrast to the negative aspects of BEVs, there are also positive aspects that are primarily related to the comfort of drivers and passengers, considering the main fact that they do not require the presence of a floor tunnel. In this paper, trends related to BEVs in the previous five years were statistically analysed. Changes in average sizes related to BEVs are shown, primarily internal dimensions that can be of crucial importance when deciding between BEVs and conventional vehicles. In the paper itself, other important trends are presented, both for the electric motor itself and for the batteries used in BEVs.
PL
Detekcja impulsów w odebranym sygnale radiowym, zwłaszcza w obecności silnego szumu oraz trendu, jest trudnym zadaniem. Artykuł przedstawia propozycje rozwiązań wykorzystujących sieci neuronowe do detekcji impulsów o znanym kształcie w obecności silnego szumu i trendu. Na potrzeby realizacji tego zadania zaproponowano dwie architektury. W pracy przedstawiono wyniki badań wpływu kształtu impulsu, mocy zakłóceń szumowych oraz trendu obecnego w sygnałach wejściowych sieci, na skuteczność detekcji zaproponowanych rozwiązań.
EN
Detecting pulses in a received radio signal, especially in the presence of strong noise and trend, is a difficult task. The article presents proposed solutions based on neural networks for the detection of pulses of known shape in the presence of strong noise and trend. Two architectures are proposed for the purpose. The paper presents the results of the study of the influence of the pulse shape, the noise power, and the trend present in the input signals of the network on the detection performance of the proposed solutions.
EN
The investigation of extreme meteorological drought events is crucial for disaster preparedness and regional water management. In this study, trends in extreme drought events, namely annual maximum drought severity (AMDS) and annual maximum drought duration (AMDD), were examined for the Ceyhan Basin. The analyses of extreme events were conducted using the standard precipitation index (SPI) index for multiple-time scales of 1, 3, 6, 9, and 12 months for 23 meteorological stations located in the Ceyhan Basin, Turkey. The Wallis-Moore and Wald-Wolfowitz methods were employed to determine the homogeneity of the data sets, whereas trend analyses were conducted using Mann-Kendall and Spearman Rho tests. The magnitude of trends was defined by Sen’s slope and linear regression, and change points were detected using the standard normal homogeneity test, Buishand’s range test, and Pettitt’s test. Although increasing trends were detected in most of the stations, only in nine of them, statistically significant results were noted at a significance level of 95%. The results of this paper provide valuable information to water resource management decision-makers in the Ceyhan River Basin for evaluating the effect of droughts and preparing for drought mitigation measures to avoid future drought risks.
6
Content available remote Beton niskoemisyjny - perspektywy rozwoju
PL
Zgodnie z danymi statystycznymi z zakresu rewitalizacji, zebranymi przez Główny Urząd Statystyczny w 2018 r., pod względem ilościowym 61% gmin w Polsce prowadzi działania rewitalizacyjne. Co 5 mieszkaniec Polski objęty jest procesami rewitalizacji. Ale pomimo upowszechnienia się polityki rewitalizacyjnej w Polsce tylko niewielka część gmin korzysta z rozwiązań ustawy o rewitalizacji (dalej: ustawa).
EN
Hydrometeorological variables are tested by trend methods to detect trends in river basins. Mann-Kendall and Spearman’s rho tests are widely used as traditional trend methods. Besides, some new trend tests are applied to hydrometeorological variables, such as Innovative Trend Analysis (ITA). Sediment discharge observations are more complicated than other hydrometeorological variables. In general, sediment data are observed on a monthly time scale. Therefore, there are minimal studies on sediment data, especially in Turkey. In this study, Innovative Trend Analysis (ITA), Mann-Kendall, Correlated Mann-Kendall and Seasonal Mann-Kendall trend analyses are applied to sediment discharges in Turkish river basins. According to Mann-Kendall, Correlated Mann-Kendall and Seasonal Mann-Kendall results, positive trends have detected only 8, 2 and 20 gauging stations, respectively. Then, 30 positive and 15 negative trends were detected by ITA methodology. The trend slopes calculated from ITA methodology are categorised because some positive and negative trends are weak. The applied trend methods are evaluated together, considering the climate properties of hydrological regions in Turkey. Increasing trends in sediment data are detected from the rivers in the Mediterranean region of Turkey. The results of the study would help to manage water resources as well as sustainable development in the Turkish river basins.
PL
Wieżowce choć istnieją od niedawna, stały się dominującymi elementami w strukturze miejskiej. Jest to grupa budynków, które wywołują najwięcej kontrowersji pod względem ich wpływu na kształtowanie miast. Jednak jest to również dziedzina w architekturze oraz w budownictwie, którą cechują najbardziej przełomowe odkrycia w dziedzinie nowych materiałów i technologii, a także rekordowe pod względem wysokości rozwiązania konstrukcyjne.
EN
The skyscrapers prevail for a brief period, but they immediately became the elements that clearly dominates the city structure. This group of buildings are the most controversial due to their significant impact on creating cities novadays. However, this particular sort of architecture and construction is specified by the most groundbreaking discoveries in terms of using new materials, technologies, as well as record-breaking construction solutions, especially, according to their height and innovate shape and system.
EN
In the late 20th century, warming on the Antarctic Peninsula was most pronounced compared to other parts of Antarctica. However, air temperature showed a significant variability, which has become especially evident in recent decades. Thus, the investigation of air temperature trends on the Antarctic Peninsula is important. This study examines the extreme air temperature at the Ukrainian Antarctic Akademik Vernadsky station, located on Galindez Island, Argentine Islands Archipelago, near the Antarctic Peninsula. For 1951 to 2020, based on the daily air temperature data, the temporal trends of extreme air temperature were analyzed, using 11 extreme temperature indices. Based on linear trend analysis and the Mann-Kendall trend test, the TXn, TNn, TN90p, and TN90p indices showed an upward trend, whereas theFD0, ID0, TN10p, TX10p, and DTR indices showed a downward trend. Among them, annually, FD0, ID0, and TN10p significantly decreased by –0.427 days, –0.452 days, and -0.465%, respectively, whereas TXn and TNn increased by 0.164℃ and 0.201℃, respectively. The indices TXx and TNn showed no statistically significant trends. The average annual difference between TX and TN (index DTR) showed a nonsignificant decreasing trend at –0.029℃ year-1 . Thus, for the period of 1951-2020, the Ukrainian Antarctic Akademik Vernadsky station was subjected to warming.
11
Content available remote Rozwój konstrukcji murowych w Polsce
PL
Konstrukcje murowe w Polsce przez ostatnie dwadzieścia pięć lat mocno się rozwinęły. Wprowadzono nowe elementy murowe i zaprawy, dzięki czemu mury wznosi się obecnie szybciej i dokładniej. Zwiększono wymagania dotyczące parametrów mechanicznych, cieplnych i akustycznych ścian murowanych. Opracowano zaprawy do cienkich spoin oraz kleje do łączenia elementów murowych. W artykule przedstawiono stan obecny i perspektywy rozwoju konstrukcji murowych.
EN
Masonry structures in Poland have developed significantly over the last twenty-five years. New masonry elements and mortars were introduced, thanks to which the walls are now erected faster and more accurately. The mechanical, thermal, and acoustic parameters of masonry walls were increased. Mortars for thin joints and adhesives for joining masonry elements have been developed. The article presents state and development prospects of masonry structures.
EN
A fast-and-flexible method of ARIMA model optimal selection is suggested for univariate time series forecasting. The method allows obtaining as-highly-accurate-as-possible forecasts auto-matically. It is based on effectively finding lags by the autocorrelation function of a detrended time series, where the best-fitting polynomial trend is subtracted from the time series. The fore-casting quality criteria are the root-mean-square error (RMSE) and the maximum absolute error (MaxAE) allowing to register information about the average inaccuracy and worst outlier. Thus, the ARIMA model optimal selection is performed by simultaneously minimizing RMSE and Max-AE, whereupon the minimum defines the best model. Otherwise, if the minimum does not exist, a combination of minimal-RMSE and minimal-MaxAE ARIMA models is used.
PL
W pracy zaproponowano szybką i elastyczną metodę optymalnego doboru modelu ARIMA na potrzeby prognozowania szeregów czasowych z jedną zmienną. Metoda pozwala na uzyskanie możliwie najdokładniejszych prognoz, opierając się na skutecznym znajdowaniu opóźnień. Po-szukiwanie opóźnień realizowane jest za pomocą funkcji autokorelacji szeregu czasowego bez trendu, w którym najlepiej dopasowany trend wielomianowy jest odejmowany od szeregu cza-sowego. Za kryteria jakości prognozowania przyjęto średni błąd kwadratowy (RMSE) i maksy-malny błąd bezwzględny (MaxAE), które pozwoliły na rejestrację informacji o średniej i maksymalnej niedokładności. Optymalny dobór modelu ARIMA odbywa się poprzez jednoczesną minimalizację RMSE i MaxAE, dla której wartość minimalna określa najlepszy model. W przeciw-nym razie, jeśli minimum nie istnieje, używana jest kombinacja modeli ARIMA z minimalnym RMSE i minimalnym MaxAE.
13
EN
This research study aims at examining the long-term trend of EV sales in Thailand, utilising the system dynamics (SD) modelling approach. This approach is commonly used to model complex systems with causal relationships among key factors within the system. The developed SD model consists of five key factors affecting electric vehicle (EV) sales, namely, the environment, economy, charging infrastructure, government support, and battery maintenance. The simulation results show the increase in EV sales by ten times in the next 20 years with implementation plans related to the five key factors. The government support factor is the most important in enhancing EV sales in the short term. Several government support plans should be initiated to attract more EV consumers, such as subsidies and tax reductions. The environment and charging infrastructure factors are crucial to increasing EV sales in the long term. The enforcement of the CO2 tax and the provision of charging stations all around the country should be established to achieve a sustainable EV market in the long term. This research study contributes to the Thai government and automotive industry to better understand the complex relationships among key factors affecting EV sales. The related sectors may use the study results to plan for EV campaigns to promote the use of EVs and achieve a sustainable EV market.
PL
Rozwój technologii betonu przebiega w kierunku uzyskania betonu o dobrze zdefiniowanej użyteczności, o minimalnym wpływie na środowisko, betonu trwałego i wytrzymałego, łatwego i możliwie samoobsługowego w wykonaniu i użytkowaniu oraz o szczególnych, dodatkowych funkcjonalnościach. W artykule omówiono kierunki rozwoju współczesnej technologii betonu w aspektach technicznym, ekonomicznym i ekologicznym. Pokazano, że chociaż koszt nowoczesnego betonu jest coraz większy, jego stosowanie umożliwia projektowanie mniej kosztownych konstrukcji betonowych, obniżenie pracochłonności i energochłonności ich wykonania, a dzięki lepszej odporności na agresywne oddziaływanie środowiska – dłuższy okres użytkowania konstrukcji.
EN
The development of concrete technology is going in the direction of obtaining concrete of well-defined usability, with minimum environmental impact, durable and strong, easy and possibly self-service in production and use, and with special additional functionalities. The paper discusses the directions of development of modern concrete technology in technical, economic and ecological aspects. It is shown that although the cost of modern concrete is increasing, its use allows for the design of less expensive concrete structures, reduction of labour and energy consumption during construction, and thanks to better resistance to aggressive environmental impact, longer service life of structures.
EN
The analysis of long-term rainfall data in a changing climate is important because it has many sectoral applications such as agriculture, infrastructure, and water resources management. Statistical analyses of the annual maximum rainfall data were performed using the Mann–Kendall (MK) trend test to evaluate the annual maximum trend characteristics of the rainfall time series, the innovative trend analysis (ITA) method to detect categorial trends, and the ITA indicator to digitize the ITA results. Storm durations of 5, 10, 15, 30 min and 1, 3, 6, 24 h annual maximum rainfall series at 13 central stations in Central Anatolia, Turkey were used. According to the MK test results, there were no signifcant upward or downward monotonic trend at four stations, whereas the remaining nine stations showed a signifcant upward or downward monotonic trend. Signifcant negative and positive trends were identifed for the sub-hourly and hourly rainfall, whereas signifcant positive trends were detected for hourly storm durations. Signifcant trend results were mostly consistent with the general ITA results. The sub hourly storm duration data were more consistent in terms of signifcant trends. Conversely, when evaluated according to low, medium, and high data values in the rainfall series (categories), the high data values showed diferent trends. Although no trend was detected with the MK test, the ITA results showed an upward or downward trend for 25 rainfall series. 29 of 30 signifcant MK test results were consistent with the ITA indicator results, compared with 24 of 30 results of the visually inspected ITA results.
17
Content available remote Trend and nonstationary relation of extreme rainfall: Central Anatolia, Turkey
EN
The frequency of extreme rainfall occurrence is expected to increase in the future and neglecting these changes will result in the underestimation of extreme events. Nonstationary extreme value modelling is one of the ways to incorporate changing conditions into analyses. Although the defnition of nonstationary is still debated, the existence of nonstationarity is determined by the presence of signifcant monotonic upward or downward trends and/or shifts in the mean or variance. On the other hand, trend tests may not be a sign of nonstationarity and a lack of signifcant trend cannot be accepted as time series being stationary. Thus, this study investigated the relation between trend and nonstationarity for 5, 10, 15, and 30 min and 1, 3, 6, and 24 h annual maximum rainfall series at 13 stations in Central Anatolia, Turkey. Trend tests such as Mann– Kendall (MK), Cox–Stuart (CS), and Pettitt’s (P) tests were applied and nonstationary generalized extreme value models were generated. MK test and CS test results showed that 33% and 27% of 104 time series indicate a signifcant trend (with p<0.01–p<0.05–p<0.1 signifcance level), respectively. Moreover, 43% of time series have outperformed nonstationary (NST) models that used time as covariate. Among fve diferent time-variant nonstationary models, the model with a location parameter as a linear function of time and the model with a location and scale parameter as a linear function of time performed better. Considering the rainfall series with a signifcant trend, increasing trend power may increase how well fitted nonstationary models are. However, it is not necessary to have a signifcant trend to obtain outperforming nonstationary models. This study supported that it is not necessarily time series to have a trend to perform better nonstationary models and acceptance of nonstationarity solely depending on the presence of trend may be misleading.
18
Content available remote Quantile trends of subhourly extreme rainfall: Marmara Region, Turkey
EN
Global climate change will probably cause intensification of the hydrologic cycle, which can lead to alterations in extreme precipitation properties. In this study, we investigated the trend of 5-, 10-, 15-, and 30-min annual maximum rainfall series at 12 stations in the Marmara Region, Turkey, using quantile regression. The data ranges were from 46 to 71 years long. Five quantiles were used to examine the extreme rainfall series, and their quantile regression parameters were calculated. The results show that quantile regression is a powerful tool to compute trends with a more inferential context, which was validated with the notable differences between the trends at chosen quantiles and the classical ordinary least squares method. Concerning the problem of the analysis of climate trends, the quantile regression method seems to provide a perspective from a more detailed understanding of processes in the climate system in terms of characteristics of climate variability and extremity.
19
PL
W pracy analizowano zawartość ozonu w całej kolumnie atmosfery i wybranych warstwach (troposfera/dolna stratosfera, środkowa stratosfera i wysoka stratosfera) zmierzone spektrofotometrem Dobsona w Centralnym Obserwatorium Geofizycznym Instytutu Geofizyki Polskiej Akademii Nauk w Belsku (20,78°E, 51,84°N) w latach 1963-2018. Stwierdzono zatrzymanie spadkowej tendencji w połowie lat 90. ubiegłego wieku, a następnie niewielki wzrost zawartości ozonu. W ostatnich kilkunastu latach w analizowanych warstwach obserwuje się nieoczekiwane beztrendowe oscylacje ozonu w miejsce spodziewanego stopniowego wzrostu w związku ze zmniejszającą się koncentracją w stratosferze substancji niszczących warstwę ozonową w wyniku funkcjonowania Protokołu Montrealskiego z 1987 r. o ochronie warstwy ozonowej. Wyznaczono długookresowe zmiany w kolumnowej zawartości ozonu nad wybranymi obszarami na półkuli północnej, stosując homogenizowane satelitarne dane ozonowe z bazy danych Multi-Sensor Reanalysis version 2. Przedmiotem analizy były sezonowe i całoroczne średnie w okresie 1979-2018 wyznaczone dla następujących obszarów: otoczenie Belska, Polska, Europa Środkowa, Europa, pas średnich (30-60°N) i wysokich (60-90°N) szerokości geograficznych, oraz tropiki (0°-30°N). Antropogeniczny trend obliczono, stosując model regresji wieloskładnikowej, odfiltrowując z serii czasowych oscylacje związane z naturalnymi procesami dynamicznymi w atmosferze. Do połowy lat 90. ubiegłego wieku dominowały ubytki w warstwie ozonowej w tempie kilku procent na 10 lat (największe wiosną w Polsce i Europie Środkowej ~5% na 10 lat, najmniejsze w tropikach ~0,5% na 10 lat). Naprawę warstwy ozonowej po 1996 roku, w tempie ~4-5% na 10 lat, najwyraźniej widać zimą w Polsce i w Europie Środkowej. Odpowiadające wzrostowe trendy w całej Europie i w średnich szerokościach geograficznych były mniejsze o 1-2 punkty procentowe. W pozostałych sezonach i w danych całorocznych trend był znacznie mniejszy (~1-2% na 10 lat) lub nieistotny statystycznie.
EN
Ground-based measurements of ozone by the Dobson spectrophotometer in the Central Geophysical Observatory of the Institute of Geophysics of the Polish Academy of Sciences at Belsk (20.78°E, 51.84°N) are analysed for the period 1963-2018. Long term variability of the total column ozone and the ozone content in the selected layers (troposphere/lower stratosphere, mid- and upper stratosphere) are discussed focusing on the ozone recovery in recent years. The trend overturning is found around 1996. However, an unexpected trendless pattern of the long-term ozone variability has been found since the beginning of the 2000s instead of the envisaged continuous upward tendency due to the decreasing concentration of the ozone-depleting substances in the stratosphere as a result of the 1987 Montreal Protocol on the protection of the ozone layer. The long-term variability of the total column ozone over selected areas in the Northern Hemisphere are assessed using homogenized satellite data from the Multi-Sensor Reanalysis version 2 database. The seasonal and the yearly means for the period 1978-2018 are considered for the following regions: Belsk, Poland, central Europe, Europe, middle latitudes (30°N-60°N), high latitudes (60°N-90°N), and the tropics (0°-30°N). The anthropogenic trend is determined by multiple regression model after filtering out oscillations related to the known dynamic processes in the atmosphere. In all regions, a decline of the total column ozone is found in the 1980s and up to mid-1990s. The largest decline appears in spring in Poland and central Europe (~5% per 10 yr.), and the smallest over the tropics (-0.5% per 10 yr.). After 1996, the recovery is clearly seen (4-5% per 10 yr.) during winter in Poland and in central Europe. These estimates are about 1-2 percentage point higher than the corresponding increasing trends in Europe and in the middle latitudes. In the remaining seasonal and year-round time series, the trends are much smaller (1-2% per 10 yr.) or statistically insignificant.
20
Content available 60 lat poznańskiej wielkiej płyty
PL
Budynki mieszkalne wykonane w technologii prefabrykowanej wielkopłytowej stanowią zasadniczą część krajobrazu miasta Poznania. Najstarsze z nich istnieją już prawie 60 lat. Po tak długim okresie eksploatacji budynki wykazują oznaki zużycia technicznego i funkcjonalnego. Prawidłowo prowadzone remonty i modernizacje są w stanie poprawić warunki mieszkaniowe oraz wydłużyć życie obiektów. W artykule przedstawiono historię poznańskiego budownictwa wielkopłytowego, problemy zużycia oraz problemy eksploatacyjne. Przedstawiono kierunki i możliwości modernizacji, a także poruszono kwestię przyszłości tego typu budynków.
EN
Residential buildings made in the prefabricated large-panel technology constitute an essential part of the landscape of the city of Poznań. The oldest of them are almost 60 years old. After such a long period of use, the buildings are showing signs of technical and functional wear. Properly conducted renovations and modernizations can improve the housing conditions and extend the life of the buildings. The article presents the history of Poznań large-panel construction, problems of wear and in-use performance. It also outlines the directions and possibilities of modernization, as well as the issue of the future of this type of buildings.
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