Wyniki wyszukiwania - BazTech

1

Dependence of the basic surface parameters of metal on temperature

Chrzanowski Janusz, Marosek Konrad, Kasyk Lech

Zeszyty Naukowe Politechniki Morskiej w Szczecinie

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2025

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nr 82 (154)

5--11

EN

In this paper, the authors analyze, theoretically, the dependence of the work function on temperature within the model proposed by one of the authors in his earlier works. In accordance with the introduced analytical equation, the thermal metal expansion leads directly to changes in the electron gas density and this, in turn, modifies the value of the work function in a complicated way. The numerical calculations carried out by the authors also show changes in the chemical potential of the metal, together with the changes in temperature. Knowing the dependence of the chemical potential as well as the work function of the metal on the temperature, in the next step, the authors analyze the influence of temperature on the dipole layer on the metal surface. All the calculations are applied to the example of metals for which the dependence of work function on temperature is known from experimental research. The conducted analysis is a solid theoretical justification of the results of known experimental works carried out in this field.

2

The impact of the gas turbine blade heating temperature in the presence of aviation kerosene on coating and alloy microstructure

Bogdan Mariusz, Kułaszka Artur, Zasada Dariusz

Acta Mechanica et Automatica

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2025

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Vol. 19, no. 1

153--163

EN

Under operating conditions, gas turbine blades may experience overheating. The degree of unfavourable modifications of the condition of both the protective insulating coating and the alloy (microstructure degradation) depends, among other factors, on the temperature and its exposure time. In this study, under laboratory conditions, in the presence of aviation kerosene exhaust gases, the influence of temperature (mainly outside the range of nominal operating temperatures) on the condition of uncooled polycrystalline rotor blades of aircraft turbine jet engines was examined. The object of the research were new gas turbine blades of the SO-3 aircraft engine made of the EI-867 WD alloy, which were exposed to high temperatures for a period of two hours in a laboratory furnace in the temperature range T = 1123 - 1523K, every 100K. The article determines the nature of changes (modifications) both in the state of the coatings and in the core material (alloy). A multifactor analysis was taken into account, including in the case of coatings modifications: morphological microstructure of the coating, chemical composition of oxides and roughness parameters, and in the case of the alloy mainly grain growth, and modification of the strengthening γ' phase. As a result of exposure to high temperatures in the surroundings of exhaust gases, the roughness of the surface changes and various types of oxides are formed, and its thickness increases. An increasing number of carbides appeared in the EI-867 WD alloy and grain growth was found as a function of the heating temperature. In particular, the blade alloy structure experienced the growth of the reinforcing γ’ phase, which is adverse in terms of heat resistance, and the percentage-wise depletion of this phase in the alloy structure. Due to the aforementioned changes, heated blades experiences significant reduction in heat resistance and high-temperature creep resistance. The article also indicates the possibility of using the characteristics of microstructural changes to determine the technical condition of the tested turbine element in a non-destructive way.

3

Optimisation of BELLS3 model coefficients to increase the precision of asphalt layer temperature calculations in FWD and TSD measurements

Sudyka Jacek, Mechowski Tomasz, Harasim Przemysław, Graczyk Mirosław, Matysek Andrzej

Roads and Bridges - Drogi i Mosty

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2024

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Vol. 23, no. 4

437--456

EN

The article discusses the optimisation process of the BELLS3 model for predicting the temperature of asphalt layers, especially in deflection measurements on Polish roads. The BELLS3 model, based on data from the Long-Term Pavement Performance programme, is a popular tool for quick and non-contact temperature estimation of asphalt layers at various depths. However, its accuracy may be limited in the context of local climatic conditions, which differ from those included in the original model. In this paper, a verification analysis was carried out through testing the model on FWD measurements data, and then the model was optimised using the least squares method (LSM). This approach yielded a small improvement in accuracy (only 1%) while reducing the error to 2.12°C. Therefore, it was decided to extend the analysis by using a machine learning method (MARS) to obtain the explicit form of the model. The solution improved the accuracy by 6%, at the same time reducing the error to 1.84°C. Based on this, further research was suggested on hybrid and AI-based models that could improve the efficiency of asphalt layer temperature forecasting under local climatic conditions.

PL

W artykule omówiono proces optymalizacji modelu BELLS3, służącego do prognozowania temperatury warstw asfaltowych, szczególnie w pomiarach ugięć na polskich drogach. Model BELLS3, oparty na danych z programu Long-Term Pavement Performance, jest popularnym narzędziem umożliwiającym szybkie i bezkontaktowe oszacowanie temperatury warstw asfaltowych na różnych głębokościach. Jednakże jego dokładność może być ograniczona w kontekście lokalnych warunków klimatycznych, które różnią się od tych uwzględnionych w oryginalnym modelu. W pracy przeprowadzono analizę weryfikacyjną, testując model na danych z pomiarów FWD, a następnie dokonano jego optymalizacji za pomocą metody najmniejszych kwadratów (MNK). To podejście dało niewielką poprawę dokładności (zaledwie o 1%) przy jednoczesnej redukcji błędu do 2,12°C. Dlatego zdecydowano o rozszerzeniu analizy o zastosowanie metody uczenia maszynowego (MARS), która pozwala na uzyskanie postaci jawnej modelu. Rozwiązanie to poprawiło dokładność o 6%, redukując błąd do 1,84°C. Na tej podstawie zasugerowano dalsze badania nad modelami hybrydowymi i opartymi na sztucznej inteligencji, które mogłyby zwiększyć skuteczność prognozowania temperatury warstw asfaltowych w lokalnych warunkach klimatycznych.

4

The influence of urban building orientation on the risk of heat stress from being in the courtyard area during the peak summer period

Voloshkina Olena, Tkachenko Tetiana, Sviatohorov Illia, Bereznytska Yuliia

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2024

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Vol. 33, No. 4

388--400

EN

Research contains assessing of the risk of heat stress and the improvement of the comfort of being outdoors for the urban population. The specialized TownScope program, banks of monitoring data of the Copernicus Climate Change Service and the Borys Sreznevsky Central Geophysical Observatory were used for the calculations. Calculations were made for the first climatic zone of Ukraine. On the example of the city of Kyiv and the Kyiv region, a widespread U-shaped construction scheme of a five-section, nine-story residential building was chosen. In the calculations, the influence of the surrounding buildings was excluded, and the surface of the courtyard was decided to be free of trees and bushes to exclude the influence of unpredictable shading in the calculations. To obtain calculation data, the authors prepared a corresponding 3D model of the building and exported it to the 3Ds format. The temperature of the facades and the courtyard at different orientations with respect to the cardinal points was calculated. Graphs of the dependence of the amount of direct solar radiation falling on the surface per hour during daylight hours are plotted. The heating temperature of the surfaces of building facades and the underlying surface from solar radiation during one hour of daylight was determined according to the formula of A.M. Shklover. This research makes it possible to apply relevant innovative technologies of “green construction” both at the design stage and during the operation of the existing building.

5

Symulacyjne badanie właściwości dynamiczno-termicznych ultra-szybkiego napędu indukcyjno-dynamicznego

Jankowski Piotr, Hallmann Damian

Przegląd Elektrotechniczny

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2024

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R. 100, nr 2

203--208

PL

W artykule przedstawiono wyniki badań ultraszybkiego napędu indukcyjno-dynamicznego o dużej energii początkowej baterii kondensatorów. Celem badań było symulacyjne określenie właściwości dynamicznych i termicznych, na podstawie których można wyznaczyć parametry krytyczne zasilania i wymiary cewki miedzianej oraz dysku dwuwarstwowego gwarantujące powtarzalną pracę napędu. Wyznaczone parametry muszą zapewniać oczekiwaną dynamikę poruszającego się dysku nie przekraczając przy tym dopuszczalnej temperatury cewki i dysku.

EN

The article presents the results of research on an ultra-fast induction-dynamic drive with a high initial energy of a capacitor bank. The aim of the research was to simulate the dynamic and thermal properties on the basis of which it is possible to determine the critical parameters of the copper coil and the double-layer disc, guaranteeing repeatable operation of the drive. The determined parameters must ensure the expected dynamics of the moving disc without exceeding the permissible temperature of the coil and the disc.

6

New ecological notes on the freshwater chrysophycean alga Hydrurus foetidus (Chrysophyceae, Heterokontophyta) : a study from Serbia (Southeast Europe)

Rakonjac Aleksandra B., Simić Snežana B.

Oceanological and Hydrobiological Studies

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2024

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Vol. 53, No. 4

375--385

EN

Hydrurus foetidus (Chrysophyceae, Ochrophyta) is a freshwater benthic alga that appears as a mucilaginous, filamentous thallus. It is geographically widespread but restricted to cold waters, with optimal temperatures for growth between 2°C and 12°C. The lethal temperature for this alga is 16°C. This paper reports the second occurrence of H. foetidus in waters with temperatures much above the recorded lethal temperature. In addition, we describe the non-obligate Hydrurus–Paralemanea association for the first time, with Paralemanea being a substrate for Hydrurus growth. This non-obligate association may be a strategy for the species’ survival during the summer season or the species’ response to climate change. Furthermore, we present co-occurring macroalgae, with special emphasis on the first finding of the rare freshwater chrysophycean alga Phaeodermatium rivulare in Serbian aquatic ecosystems.

7

The use of Argo floats as virtual moorings for monitoring the South Baltic Sea

Merchel Małgorzata, Walczowski Waldemar, Rak Daniel, Wieczorek Piotr

Oceanologia

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2024

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No. 66 (1)

99-110

EN

The Argo float measurement network is increasingly effectively covering internal seas and shelf areas. In this paper, a specific approach to using Argo floats as ‘virtual moorings’ within the conditions of the Baltic Sea is presented. Following a series of successful deployments with standard configurations, it was decided that the settings forcing the float to stay at the bottom between profiles should be tested. This significantly reduced the drift of the float and allowed measurements to be made in a limited water area for a longer time. The data obtained from Argo floats used as virtual mooring can be a valuable source for monitoring and analysing the hydrology of individual basins of the Baltic Sea. The results show that the temporal and spatial variability of the observed fields of temperature, salinity, and other properties of seawater is very high. More data are needed to correctly determine the mean properties of the basins and their temporal variability. Therefore, Argo floats can be a source of efficient and inexpensive hydrographic data for shallow seas such as the Baltic.

8

Cooperation between the fishery sector and science : CTD probe measurements during fishing catches on the feeding grounds of herring (Culpea harengus) and sprat (Sprattus sprattus) in the south-eastern part of the Baltic Sea

Pieckiel Piotr, Dziaduch Diana, Dzierzbicka-Głowacka Lidia, Kalarus Marcin

Oceanologia

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2024

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No. 66 (2)

167--179

EN

282 CTD probe measurements were analysed for the parameters of temperature, salinity, depth and oxygen saturation of the water column. These measurements were taken during commercial pelagic fishing for herring (Clupea harengus) and sprat (Sprattus sprattus). These species are currently the main target of commercial fishing in the Baltic Sea. Research was carried out throughout the years 2018–2022 in the south-eastern Baltic Sea, mainly in the Gdańsk Deep, mostly during the daytime. The main factor that influenced both, fishing strategy and the increase in catch per unit effort throughout each year, was temperature. Regardless of the season, the most frequent temperature measured was around 5.8°C during fishing, and 5°C in the most abundant winter season. This is the value occurring within the boundaries of the formation of the thermocline and the hypolimnion layer in the Baltic Sea. The formed shoals of fish moved dynamically with this layer in the daytime and occurred throughout the year at various depths in a range of up to 65.7 m. A stronger reaction to temperature changes was also observed for sprat, which is the most exploited fish in the Baltic Sea. This species was observed to be more numerous in the deeper layers of the water column and at lower temperatures than herring. In the winter, shoals of fish were observed at the level of the halocline, which may be strongly related to the presence of a preferred optimal food base in this season.

9

Solving the prevention of the formation of traffic jams in pipelines in the transportation of gases by the autoejection process

Gurbanov Abdulaga, Sardarova Ijabika

Nafta-Gaz

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2024

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R. 80, nr 4

252--256

EN

The article presents the application of autoejection process to ensure efficient operation of pipeline systems and gas separation installations when it is impossible to remove and utilize the condensate from the pipelines. Thus, in the suggested ejector, a single common stream is separated into two streams, i.e., an active and a passive stream, as opposed to two separate independent streams in existing ejection devices. As a result, we refer to such an ejection process as autoejection, or a self-ejection process. Such a procedure is run in the pipeline with the goal of blowing and dusting the liquid phase through the central high-velocity nozzle in circumstances of mass blocking and coating rather than expelling the liquid from the pipes. On the cross-sectional area of the belts, the velocity profiles of flows in laminar and turbulent regimes are known to differ greatly from one another. The adhesion forces acting from the tube's central axis outwards, towards its walls cause the flow rate to decrease. There is a cross-sectional interaction of flows in this mode, according to experimental studies of turbulent flows. As a result, compared to the laminar domain, the flow velocities in this regime are more equally distributed across the cross-section of the flow, and their values are roughly equal to the flow's average value. In this case, based on the dependences of the flow ∆p = f(W), it is known from the calculations and the table that at such velocity limits of the flows, the “braking” pressure (p0) of the liquid coating on the pipe walls corresponds to the maximum velocity of the central gas flow. The autoejection process can occur due to the difference between the static pressures. Unsaturated absorbent coatings can be blasted off the tube absorber's walls using this technique and blended back into the main gas stream. Gas-liquid autoejectors installed along the pipe absorber's length make it possible to use this method. The purpose and principles of autoejectors’ operation are considered and a perspective of their application in tube absorbers is noted.

PL

Artykuł prezentuje zastosowanie procesu automatycznego strumieniowania w celu zapewnienia efektywnej pracy systemów rurociągowych i instalacji separacji gazu, gdy niemożliwe jest usunięcie i wykorzystanie kondensatu z rurociągów. W związku z tym w sugerowanej strumienicy automatycznej pojedynczy wspólny strumień jest rozdzielany na dwa strumienie, czyli aktywny i pasywny, w przeciwieństwie do dwóch oddzielnych, niezależnych strumieni w istniejących urządzeniach strumieniowych. Taki proces strumieniowania nazywany jest automatycznym strumieniowaniem lub procesem samostrumieniowania. Procedura ta uruchamiana jest w rurociągu w celu przedmuchiwania i odpylania fazy ciekłej przez centralną dyszę o wysokiej prędkości w warunkach masowego blokowania i usuwania, a nie wypierania cieczy z rur. Wiadomo, że profile prędkości przepływów w reżimach laminarnym i turbulentnym w przekroju poprzecznym stref znacznie się od siebie różnią. Siły adhezji działające od centralnej osi rury na zewnątrz w kierunku jej ścian powodują spadek prędkości przepływu. Zgodnie z wynikami badań eksperymentalnych przepływów turbulentnych w tym trybie występuje interakcja przepływów w przekroju poprzecznym. W rezultacie, w porównaniu do domeny laminarnej, prędkości przepływu w tym reżimie są bardziej równomiernie rozłożone w przekroju przepływu, a ich wartości są mniej więcej równe średniej wartości przepływu. W tym przypadku, na podstawie zależności przepływu ∆p = f(W), wiadomo z obliczeń i tabeli, że przy takich granicach prędkości przepływów, „hamujące” ciśnienie (p0) powłoki cieczy na ścianach rurociągu odpowiada maksymalnej prędkości centralnego przepływu gazu. Proces automatycznego strumieniowania może zaistnieć dzięki różnicy między ciśnieniami statycznymi. Nienasycone powłoki absorbujące mogą być zdmuchiwane ze ścian absorbera rurociągu przy użyciu tej techniki i ponownie mieszane z głównym strumieniem gazu. Wykorzystanie tej metody jest możliwe dzięki zastosowaniu automatycznej strumienicy gazowo-cieczowej zainstalowanej wzdłuż absorbera rurociągu. Artykuł zawiera również rozważania dotyczące celu stosowania i zasad działania strumienic automatycznych, zwracając uwagę na ich zastosowania w absorberach rurociągowych.

10

Cylindrical gear transmission errors influenced by temperature based on thermal network

Tang Jie, Guo Heng, Wan Hui

Metrology and Measurement Systems

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2024

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Vol. 31, nr 1

3--21

EN

Gear transmission errors are influenced by temperature especially in the aerospace field. A model is proposed to investigate the influence of temperature on cylindrical gear transmission errors based on the thermal network (TETN). The gear temperature field distribution model is established based on the thermal network method, and gear thermal deformation can be calculated along the gear meshing line. Regarding the gear single-flank rolling process, the variation of gear transmission errors under temperature is determined. In numerical calculations in MATLAB, the variation of gear transmission errors at 100˚C compared to 20˚C is -4.20 μm, which decreases almost linearly while the thermal expansion coefficient of the gear material increases. The simulation of the gear transmission errors variation of temperatures using the finite element method (FEM) were carried out in Workbench software under Ansys and the average difference of the TETN model results between calculations and FEM for different temperatures was 0.24 μm. Experiments were carried out on the gear tester in temperatures ranging from 0˚C to 100˚C, the TETN model results in calculations were compared with the results of the tester, and the average difference was -1.15 μm. The results show that the proposed TETN can be used as an algorithm to determine the variation of gear transmission errors under the influence of temperature.

11

The influence of temperature on the assessment of the load-bearing capacity of concrete airport pavements

Grabowski Paweł, Wesołowski Mariusz, Blacha Krzysztof

Materiały Budowlane

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2024

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nr 11

97--106

EN

The aim of the work was to determine the influence of temperature on the airfield pavement’s elastic deflections and therefore the load-bearing capacity results. The article presents the research carried out on the cement concrete test section and the obtained data presenting the impact of the discussed phenomenon on measurements. The article summarizes the research conducted on the influence of temperature changes on the obtained load-bearing capacity results, presents general conclusions and proposals for further work on the topic.

PL

Celem badań było określenie wpływu temperatury na uzyskiwane wyniki pomiarów ugięć sprężystych nawierzchni betonowych, a w efekcie ich nośności. W artykule przedstawiono badania realizowane na testowym odcinku wykonanym z betonu cementowego oraz uzyskane dane, ilustrujące wpływ omawianego zjawiska na pomiary. Dokonano podsumowania przeprowadzonych badań w zakresie wpływu zmian temperatury na uzyskane wyniki nośności, przedstawiono ogólne wnioski oraz propozycje dalszych prac w podjętym temacie.

12

Selection of high-sorption clay-based plaster for machine application

Byrdy Aleksander, Rembiś Marek, Kinasz Roman

Materiały Budowlane

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2024

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nr 7

12--23

EN

Modern ready mixed clay-based plasters contain a substantial amount of additives and fillers that are indispensable to make typical machine-assisted plaster application feasible. Fillers reduce the content of clay as the primary ingredient improving the indoor climate in rooms. This article presents the results of comparative studies on the sorption parameters of various clay-rich plaster compositions against the backdrop of research results for other plasters commonly used in building engineering. A plaster characterized by high sorption properties was selected and verified in terms of application potential using the shotcreting technique taking advantage of the thixotropic properties of the material. The developed composition was applied as plaster in a residential building where its effectiveness and influence on the indoor comfort in rooms were verified.

PL

Współcześnie stosowane tynki maszynowe produkowane na bazie gliny zawierają znaczną ilość dodatków i wypełniaczy, które mają zapewnić możliwość ich aplikacji przy użyciu typowych agregatów tynkarskich. Wypełniacze te redukują zawartość gliny jako podstawowego składnika wpływającego na poprawę klimatu wewnętrznego w pomieszczeniach. W artykule przedstawiono wyniki badań porównawczych parametrów sorpcyjnych różnych receptur tynków o dużej zawartości gliny na tle wyników badań innych tynków powszechnie stosowanych w budownictwie. Na podstawie przeprowadzonej selekcji dobrano tynk o bardzo dobrych właściwościach sorpcyjnych i zweryfikowano możliwość jego aplikacji techniką torkretowania, wykorzystującą właściwości tiksotropowe użytego materiału.

13

The effect of meteorological conditions on the course of development stages and yield of winter wheat in southern Poland

Skowera Barbara, Kulig Bogdan, Ziernicka-Wojtaszek Agnieszka, Grygierzec Wiesław, Ziółkowska Elżbieta, Lepiarczyk Andrzej

Journal of Water and Land Development

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2024

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no. 60

157--166

EN

Yield and the course of crop vegetation are the result of the interaction between the level of cultivation technology and the course of meteorological conditions, which are a variable production factor. The aim of the study was to quantify the effect of meteorological conditions on the course of development stages and yield of winter wheat cultivated in two technological variants (A1 - medium-intensive and A2 - intensive). The paper uses data on yield and timing of winter wheat development stages from four Experimental Stations for Variety Testing (Pol. Centralny Ośrodek Badania Odmian Roślin Uprawnych - COBORU) experimental stations from 2007-2016 located within the Upper Vistula and Upper Oder River basins. To determine the dependence of the length of development stages of winter wheat on the values of selected meteorological elements, the linear regression metod, correlation coefficient. It was found that the lengths of the selected developmental stages are positively correlated with air temperature and negatively correlated with the sum and number of days with precipitation in these stages. A 1°C increase in air temperature resulted in a shortening of the shooting - heading and heading - full maturity periods by 2.5 and 2.8 days respectively. An increase of 100 mm of precipitation in the periods sowing - full maturity and heading - full maturity resulted in an increase of these periods by 5 and 10 days. Increasing the number of days with precipitation by 10 days in the sowing - full maturity and heading - vax maturity stages resulted in extending these stages by 4.1 to 4.4 and 7 to 7.5 days for the A1 and A2 cropping technologies, respectively.

14

The Climate Change Impact on the Development of Droughts in Ukraine

Polevoy Anatoly, Barsukova Olena, Husieva Kateryna, Zhygailo Olena, Volvach Oksana, Kyrnasivska Nataliia, Tolmachova Alla, Zhygailo Taras, Danilova Nataliia, Kostiukievych Tetiana

Journal of Ecological Engineering

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2024

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Vol. 25, nr 6

194--205

EN

The paper considers the peculiarities of the climate change influence on the dynamics of drought development in Ukraine. The analysis was performed for average long-term climatic conditions during the growing season (1981–2020) and under climate change scenarios RCP 4.5 and RCP 8.5 for the period of 2021–2050 (for the period as a whole and by the decades: 2021–2030, 2031–2040, 2041–2050). The drought development was studied over relatively short periods of time (ten days) at the main agroclimatic regions of Ukraine (Polissia, Forest-Steppe, Northern and Southern Steppe). The assessment of the aridity of ten-day periods was accomplished by means of a set of aridity indicators by Selyaninov, Shashko, Budagovskiy and Bova, which corrects and supplements each other; this made it possible to consider in detail the genesis of climate-induced drought in the agroclimatic regions of Ukraine. Analysis of the study results showed that the development of drought conditions in all agroclimatic regions is expected as early as in the first decade (2021–2030). According to both scenarios, from 4–6 in Polissia to 16–17 severe and very severe droughts in the Southern Steppe are expected. In the second decade (2031–2040), under RCP4.5, improvement in moistening conditions is expected in Polissia and Forest-Steppe and under RCP8.5, an increase in the level of aridity is expected in these agroclimatic regions. In the Northern Steppe and Southern Steppe the number of moderately, very and extremely dry ten-day periods will increase (from 9 to 17). In the third decade (2041–2050), under the RCP4.5 scenario, very severe aridity conditions are assumed in all agroclimatic regions. Under RCP8.5, good moistening conditions and, according to both criteria, a small number of dry ten-day periods are expected in Polissia and Forest-Steppe. As for the conditions at the Northern and Southern Steppes very severe drought conditions are expected (from 8 to 17 ten-day periods with moderate, severe and very severe drought). For 2021–2050 on the whole, there will be an increase in aridity during the growing season in all agroclimatic regions of Ukraine.

15

Effect of welding environment on fatigue crack growth rate of aluminium alloy 1100

Bintoro S. R., Putri E. D. W. S., Suhartono A., Muhayat N., Badaruddin M., Fauzun, Triyono

Journal of Achievements in Materials and Manufacturing Engineering

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2024

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Vol. 122, nr 2

49--60

EN

Purpose: Aluminium is a light metal that is widely used in industry because it has good machinability, good corrosion resistance has good machinability, good corrosion resistance, and high ductility. In its application to the vehicle structure, the welding process requires a connection process. However, aluminium welding has several problems because aluminium has high thermal conductivity, a large coefficient of expansion, specific gravity and a low melting point. So, this study aims to determine the difference in fatigue crack growth rate of welded joints from different welding environmental conditions such as air humidity and air temperature. Design/methodology/approach: Fatigue crack growth rate on Al 1100, which is welded using Metal Inert Gas (MIG) welding in an isolated welding room and controlled relative humidity and temperature parameters during the welding process. Findings: A fatigue crack growth rate increases as the welding chamber's humidity and air temperature parameters decrease. A large amount of porosity, transgranular fatigue crack growth behaviour, and quasi-cleavage fault morphology occurred at high welding chamber temperature and humidity due to the influence of hydrogen and oxygen in the welding process. Research limitations/implications: It is recommended to continue to study the characteristics of the fatigue crack growth rate characteristics of other materials or dissimilar metal joints in a controlled welding room with various other parameters. Practical implications: As information and material for consideration for similar research, design a good aluminium welding chamber to minimise defects in welded joints. Originality/value: The originality of the article shows the results of experimental data on the study of FCGR characteristics and fracture characteristics of Al-1100 welding joints in a controlled welding room.

16

Wpływ sposobu docieplenia budynku jednorodzinnego niepodpiwniczonego na temperaturę na powierzchni wewnętrznej ściany oraz na liniowy współczynnik przenikania ciepła

Leszczyński Cezary

Izolacje

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2024

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T. 29, nr 11/12

110--113

PL

W artykule przeanalizowano wybrane aspekty projektowe dotyczące ocieplenia ściany istniejącego budynku. Wykonano obliczenia dla pięciu stref klimatycznych, wyróżniając różną głębokość posadowienia budynku oraz temperaturę zewnętrzną. Budynek posadowiony na fundamencie tradycyjnym, wykonany z cegły kratówki. Artykuł przedstawia analizę temperaturową występującej na powierzchni wewnętrznej ϑimg w miejscu krytycznym węzła oraz analizę liniowego współczynnika przenikania ciepła ψim mostka termicznego. Na podstawie obliczeń wykonanych w programie THERM przedstawiono zestawienie temperatur, wartości liniowych współczynników przenikania ciepła oraz wnioski. Informacja może być przydatna dla naukowców, projektantów, inżynierów przy podejmowaniu prawidłowych decyzji na etapie projektowania budynków ogrzewanych.

EN

In the article on selected design aspects concerning the insulation of the building interior. Performed for five geographical zones, different building foundations and external temperature. The building is placed on a traditional foundation, made of latticework. The article presents information on the characteristic temperature on the external surface ϑimg in the critical location and the available linear heat transfer coefficient ψim of the permeable bridge. Based on calculations in the THERM program, a comparison of temperature, values of linear heat transfer coefficients and conclusions was made. The information may be for devices, designers, engineers in the event of a failure, if there are changes in the design of heating systems.

17

The Influence of the Application of Soil Conditioners on the Temperature and Moisture of the Soil Environment

Jeřábková Jindřiška, Salaš Petr, Burgová Jana

Inżynieria Mineralna

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2024

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Vol. 1, no. 1

711--718

EN

In cities, environmental and social impacts are increased every year due to high temperatures due to the heat island of the city. An effective struggle against the heat island of the city is the green infrastructure, where woody plants such as trees and shrubs play an irreplaceable role. Wood in the city is affected by a number of stress factors, especially high temperatures and lack of precipitation. In order for them to perform all their important functions and help reduce the negative impacts of the city's heat island, all requirements for their successful development and growth must be fulfilled. Soil conditions are an important factor affecting the condition of trees. Unsuitable soil conditions which include lack of water, compacted soil, result in insufficient development of the root system which directly affects the quality of the above-ground part of the plants. A possible treatment to improve the soil environment in the root zone of trees is the use of soil conditioners applied in the form of soil injection. The paper deals with the effect of soil conditioners (Hydrogel®, mycorrhizal mix Endomyk PROF + Trichoderma, and their combination) in the form of injection on the temperature and humidity conditions of the soil environment in a young plants of trees (species) Acer campestre L. in the city of Znojmo (South Moravia region). Plants without application of any preparation served as a Control variant. Before the actual application of conditioners MINILOG data loggers with temperature sensors and VIRRIB moisture sensors were placed in the soil which recorded changes in soil temperature and volumetric soil moisture in six-hour intervals every day in the period from February 2021 till December 2022. These changes were recorded in two profiles 0.1 - 0.4 and 0.4 - 0.7 meters. From the recorded results, it can be said that the application of soil conditioners had a significant effect on the temperature and humidity conditions of the soil environment. The variant with the soil conditioner Hydrogel® and the variant with the soil conditioner Hydrogel® in combination with the mycorrhizal mix in most cases show higher values of soil moisture and temperature compared to the Control variant. This trend is most evident in the soil profile of 0.4 - 0.7 m in the growing season.

18

Diagnostyka stanu cieplno-wilgotnościowego ściany docieplonej wełną mineralną w systemie podwójnego ETICS – studium przypadku

Perkowski Zbigniew, Świrska-Perkowska Jadwiga, Marynowicz Andrzej, Czabak Mariusz, Kucharczyk Andrzej, Pawlik Kamil, Frączek Daniel, Graba Mariusz

Inżynieria i Budownictwo

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2024

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R. 80, nr 6

435--440

PL

Praca dotyczy diagnostyki stanu cieplno-wilgotnościowego ściany zewnętrznej rzeczywistego budynku docieplonego dodatkową warstwą wełny mineralnej w systemie ETICS. W czterech różnych przekrojach przegrody umieszczono po 8 czujników, zlokalizowanych na granicach jej warstw, w celu monitorowania zmian temperatury i wilgotności względnej powietrza. Pomiary prowadzono od stycznia 2024 roku. Dane otrzymane z badań eksperymentalnych porównano z obliczeniami symulacyjnymi wykorzystującymi sprzężony dwuskładnikowy model Künzela. Stwierdzono rozbieżności pomiędzy danymi eksperymentalnymi i obliczeniowymi.

EN

The work concerns the diagnostics of the thermal and humidity condition of the external wall of a real building, insulated with an additional layer of mineral wool in the ETICS system. Eight sensors were placed in four different sections of the envelope, located at the boundaries of its layers, to monitor changes in air temperature and relative humidity. The measurements were carried out from January 2024. The data obtained from the experimental tests were compared with the simulation calculations using the coupled two-component Künzel model. Discrepancies were found between experimental and computational data.

19

Field trial and performance evaluation of IoT poultry farm monitoring system

Mulya Marga A. J., Suryadi Suryadi, Nugraha Heri, Suwandi Endang, Jayadi Jayadi, Wismogroho Agus S.

International Journal of Electronics and Telecommunications

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2024

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Vol. 70, No. 2

421--428

EN

IoT technology revolutionizes poultry farming by enabling real-time data collection and analysis. Traditional manual methods for monitoring temperature, humidity, and AC voltage are being replaced with automated systems. The IoT setup includes three sensor nodes, CCTV, an IoT gateway, and a web server. Temperature ranges from 27 to 35°C in off-fattening periods and consistently above 30°C during fattening. Humidity fluctuates between 60% to 90% in both periods. The CPU temperature remains within safe limits. Uplink data rates exceed 2 Mbps, while AC voltage initially falls below standards but improves over time.

20

Heat transfer modelling in an annular disc under heating and cooling processes with stress analysis

Varhadpande Indrajeet, Murthy V. R. K., Lamba Navneet Kumar

International Journal of Applied Mechanics and Engineering

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2024

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Vol. 29, no. 3

166--181

EN

The goal of this effort is to determine the interaction among the heating and cooling processes in order to understand how solids behave when subjected to temperature changes. In this instance, the temperature, displacement, and stress relations are determined analytically and numerically while a thin annular disc is subjected to both the heating and cooling processes. The ability of a material to withstand stress is essential for the design of diverse mechanical structures that aim to enhance performance, durability, characteristics, and strength. This ability is demonstrated in many physical processes where the material structure crosses over into heating and cooling processes. Furthermore, memory derivatives used in the modelling of heat transfer equations more accurately depict the memory behaviour of an imagined disc and explain its physical significance.