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1

Trend Analysis of Aerosol Concentrations over Last Two Decades from MODIS Retrievals over Hyderabad District of India

Nandan A.K., Mathew Aneesh, Shekar Padala Raja

Geomatics and Environmental Engineering

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2024

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Vol. 18, no. 1

83--116

EN

Air pollution is one of the grave concerns of the modern era, claiming millions of lives and adversely impacting the economy. Aerosols have been observed to play a significant role in negatively influencing climatological variables and human health in given areas. The current study aimed to study the trend of aerosols and particulates on daily, monthly, seasonal, and annual levels using a 20-year (2002–2021) daily mean aerosol optical depth (AOD) product released by moderate resolution imaging spectrometer (MODIS) sensors for the Hyderabad district in India. The results of the daily mean analysis revealed a rising trend in the number of days with severe AOD (>1), whereas examinations of the seasonal and monthly mean data from 2017 through 2022 showed that peak AOD values alternated between the summer, autumn, and winter seasons over the years. Trend analysis using Mann–Kendall, modified Mann–Kendall, and innovative trend analysis (ITA) tests revealed that AOD increased significantly from 2002 through 2021 (p < 0.05; Z > 0). Furthermore, correlation analysis was performed to check for correlations between AOD levels and certain meteorological factors for the Charminar and Secunderabad regions; it was noticed that temperature had a weak positive correlation with AOD (p < 0.05; r = 0.283 [Secunderabad] – p < 0.05; r = 0.301 [Charminar]), whereas relative humidity developed a very weak negative correlation with AOD (p < 0.05; r = −0.079 [Secunderabad] – p < 0.05; r = −0.109 [Charminar]).

2

On the Correlation between Random Variables and their Principal Components

Gniazdowski Zenon

Zeszyty Naukowe Warszawskiej Wyższej Szkoły Informatyki

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2023

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nr 28

41--55

EN

The article attempts to find an algebraic formula describing the correlation coefficients between random variables and the principal components representing them. As a result of the analysis, starting from selected statistics relating to individual random variables, the equivalents of these statistics relating to a set of random variables were presented in the language of linear algebra, using the concepts of vector and matrix. This made it possible, in subsequent steps, to derive the expected formula. The formula found is identical to the formula used in Factor Analysis to calculate factor loadings. The discussion showed that it is possible to apply this formula to optimize the number of principal components in Principal Component Analysis, as well as to optimize the number of factors in Factor Analysis.

3

Assessment of the relationship between corporate social responsibility environmental goals implementation and financial and operational indicators of airlines

Savchenko Lidiia, Ovdiienko Oksana, Boichenko Mykola, Mostenska Tetiana

Zeszyty Naukowe. Transport / Politechnika Śląska

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2023

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z. 119

235--256

EN

The main idea of the article is assessing the feasibility of introducing Corporate Social Responsibility (CSR) for airlines. Moreover, the authors think that the environmental aspect in CSR is the most important, which predetermined the focus on this CSR component in the article. The article provides several examples of airlines that actively use CSR to improve their image, attract new, and increase the loyalty of existing customers. Environment indicators of the flight operations group on the performance indicators were established.

4

Critical analysis of pool boiling correlations

Radek Norbert, Orman Łukasz J., Honus Stanislav, Pietraszek Jacek

System Safety : Human - Technical Facility - Environment

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2023

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Vol. 5, iss. 1

258--265

EN

The manuscript describes the problem of boiling heat flux determination with the focus on nucleate boiling mode. It presents the boiling phenomenon on the bare surface and provides a review of the correlations that can be used for modelling purposes. Two most commonly applied correlations were validated against the experimental results. One of them showed significant discrepancies, which might be attributed to the conditions of the research and possible variations in the morphology of the heater. The other correlation proved to be successful in determining heat flux.

5

Application of deep learning techniques in identification of the structure of selected road materials

Mazurek Grzegorz, Durlej Małgorzata, Šrámek Juraj

Structure and Environment

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2023

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Vol. 15, no. 3

159--167

EN

In research, there is a growing interest in using artificial intelligence to find solutions to difficult scientific problems. In this paper, a deep learning algorithm has been applied using images of samples of materials used for road surfaces. The photographs showed cross-sections of random samples taken with a CT scanner. Historical samples were used for the analysis, located in a database collecting information over many years. The deep learning analysis was performed using some elements of the VGG16 network architecture and implemented using the R language. The learning and training data were augmented and cross-validated. This resulted in the high level of 96.4% quality identification of the sample type and its selected structural features. The photographs in the identification set were correctly identified in terms of structure, mix type and grain size. The trained model identified samples in the domain of the dataset used for training in a very good way. As a result, in the future such a methodology may facilitate the identification of the type of mixture, its basic properties and defects.

PL

W badaniach naukowych obserwuje się coraz większe zainteresowanie wykorzystaniem sztucznej inteligencji do poszukiwania rozwiązań trudnych problemów naukowych. W niniejszym artykule został zastosowany algorytm głębokiego uczenia z użyciem obrazów próbek materiałów wykorzystywanych do budowy nawierzchni drogowych. Fotografie przedstawiały przekroje losowych próbek wykonane za pomocą tomografu komputerowego. Do analizy wykorzystano próbki historyczne, znajdujące się w bazie danych zbierającej informacje z wielu lat. Analizę głębokiego uczenia wykonano przy użyciu niektórych elementów architektury sieci VGG16 i zaimplementowano, stosując język R. Dane uczące oraz treningowe poddano augmentacji oraz walidacji krzyżowej. W rezultacie uzyskano wysoki poziom 96,4% jakości identyfikacji rodzaju próbki oraz jej wybranych cech strukturalnych. Fotografie w zbiorze identyfikacyjnym zostały poprawnie zidentyfikowane pod względem struktury, typu mieszanki oraz uziarnienia. Wytrenowany model w bardzo dobry sposób zidentyfikował próbki w obszarze dziedziny trenowanego zbioru danych. W rezultacie taka metodyka może w przyszłości ułatwić identyfikację rodzaju mieszanki, jej podstawowych właściwości oraz defektów.

6

Predicting the properties of a mixture produced using “cold” technology with foamed bitumen in terms of the properties of hydraulic binder mortars

Buczyński Przemysław, Mazurek Grzegorz, Iwański Marek

Roads and Bridges - Drogi i Mosty

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2023

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Vol. 22, no. 4

363--378

EN

The paper presents the correlation between the mechanical properties of the mineral-aggregate mixture with foamed bitumen (MCAS) and the mechanical properties of mortars containing hydraulic binder. A significant aspect of the presented research results was an attempt to determine whether it is possible to predict the properties of the recycled cold mix with foamed bitumen (MCAS) based on preliminary results obtained for mortars. The prediction of MCAS properties through mortar properties was limited to basic mechanical properties of mortars, namely compressive strength (RC) and flexural tensile strength (Rf). To achieve this goal, seven hydraulic binders were designed with a controlled composition using a simplex-centroid experimental plan known as the mixture design plan. The components of the hydraulic binders used in its composition were Portland cement CEM I 32.5R, hydrated lime Ca(OH)2, and by-products of cement production in powder form (UCPP). The designed and prepared hydraulic binders were then used in the composition of the mineralaggregate mixture with foamed bitumen at a quantity of 3.0% (m/m). Subsequently, in laboratory conditions, the mineralaggregate mixture with foamed bitumen was prepared, and mechanical property tests were conducted, including indirect tensile strength (ITSDRY), axial compressive strength (UCS), modulus of stiffness (Sm), fracture toughness (KIC), and the dynamic modulus |E*| determined as a function of frequency and temperature. The analysis results suggest that there is potentially the ability to predict selected mechanical properties of the MCAS mixture by analyzing the mechanical results for mortars. However, this application is limited. The research results obtained for non-destructive properties, such as the dynamic modulus |E*|, are satisfactorily described by the compressive strength results of mortars after 28 days of curing. Other analyzed characteristics did not show a significant correlation.

PL

W artykule przedstawiono korelację pomiędzy właściwościami mechanicznymi mieszanki mineralno-spoiwowej z asfaltem spienionym (MCAS) a właściwościami mechanicznymi zapraw, w których składzie zastosowano spoiwo hydrauliczne. Istotą prezentowanych wyników badań była próba wyjaśnienia, czy za pomocą wstępnych wyników badań uzyskanych dla zapraw możliwe jest prognozowanie właściwości recyklowanej mieszanki na zimno z asfaltem spienionym (MCAS). Prognozę cech MCAS przez właściwości zapraw ograniczono do podstawowych właściwości mechanicznych zapraw, tj. wytrzymałości na ściskanie (RC) oraz wytrzymałości na rozciąganie przy zginaniu (Rf). Do osiągnięcia zamierzonego celu zaprojektowano siedem spoiw hydraulicznych o składzie kontrolowanym poprzez plan eksperymentu sympleksowo-centroidowy, zwany planem mieszaniny. Składniki spoiw hydraulicznych, które zostały wykorzystane do jego kompozycji to: cement portlandzki CEM I 32,5R, wapno hydratyzowane Ca(OH)2 oraz uboczne cementowe produkty pylaste (UCPP). Zaprojektowane i przygotowane w warunkach laboratoryjnych spoiwa hydrauliczne zastosowano w składzie mieszanki mineralno- -spoiwowej z asfaltem spienionym w ilości 3,0% (m/m). Następnie w warunkach laboratoryjnych przygotowano mieszankę mineralno- -spoiwową z asfaltem spienionym i wykonano badania właściwości mechanicznych, tj. wytrzymałość na pośrednie rozciąganie ITSDRY, wytrzymałość na ściskanie osiowe UCS, moduł sztywności (Sm), odporność na pękanie (KIC) oraz moduł dynamiczny |E*| wyznaczony w funkcji częstotliwości i temperatury. Wyniki analiz pozwalają stwierdzić, że istnieje potencjalnie możliwość prognozowania wybranych właściwości mechanicznych mieszanki MCAS dzięki analizie wyników mechanicznych dla zapraw. Ma to jednak ograniczone zastosowanie. Wyniki badań uzyskane dla właściwości nieniszczących, tj. dla modułu dynamicznego |E*|, w sposób zadowalający zostają opisane przez wyniki wytrzymałości zapraw na ściskanie po 28 dniach pielęgnowania. Pozostałe analizowane cechy nie wykazały istotnej zależności.

7

Metoda dopasowania funkcji nieliniowej do danych punktów pomiarowych i jej pasmo niepewności

Puchalski Jacek, Warsza Zygmunt Lech

Pomiary Automatyka Robotyka

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2023

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R. 27, nr 3

45--55

PL

W pracy przedstawiono propozycję metody wyznaczania parametrów i pasma niepewności funkcji nieliniowej dopasowanej do zmierzonych danych punktów badanych. By ją zlinearyzować trzeba dokonać zamiany jednej lub obu zmiennych określonej funkcji nieliniowej. Następnie metodą regresji liniowej dobrano najkorzystniejsze parametry linii prostej dopasowanej do wartości współrzędnych punktów wg ważonego ogólnego kryterium średniokwadratowego WTLS. Uwzględnia się też współczynniki autokorelacji i korelacji wzajemnej oraz niepewności obu współrzędnych oszacowane na podstawie przewodnika GUM. Z parametrów otrzymanej linii prostej i jej pasma niepewności wynikają poszukiwane parametry funkcji nieliniowej oraz jej pasmo niepewności. Podano przykłady liczbowe wyznaczania parametrów i pasma niepewności dwiema metodami dla jednej z gałęzi paraboli drugiego stopnia oraz dla złożonej funkcji wykładniczej.

EN

The paper presents a method of determining parameters and uncertainty bands of a specific non-linear function fitted to given measured data of examined points. One or both of the variables of this non-linear function are changed so as to linearize it. Using the linear regression method, fined are the most favorable parameters of this straight line for its adjustment to the measured values of the coordinates of points tested according to the weighted total mean square WTLS criterion. Their autocorrelation and cross-correlation coefficients as well as uncertainties estimated according to the rules of the GUM guide are considered. The parameters and the uncertainty band of the non-linear function result from the parameters of this straight line and its uncertainty band. Numerical examples of determining the parameters and uncertainty bands for the branch of a 2nd degree parabola (two methods) and for the complex exponential function are given.

8

Formation of the Quality Indicators of Hemp (Cannabis sativa L.) Seeds Sown under Organic Growing Technology

Pylypchenko Andrii, Marenych Mykola, Hanhur Volodymyr, Semenov Anatolii, Sakhno Tamara, Ponomarenko Serhii, Karpuk Lesia, Rozhkov Artur

Journal of Ecological Engineering

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2023

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Vol. 24, nr 8

218--227

EN

The oil content of hemp seeds is controlled by the genotype and in the conducted studies did not depend on the growing technology; however, this factor had a synergistic effect with others. The protein content of hemp seeds during the years of research did not depend on weather conditions. Like other quality indicators, it had a slight variation, which indicates the significant role of the genetic characteristics of the varieties. On average, over the years of research, the protein content of the variants grown according to conventional technology was 25.2%, and according to transitional technology, it was 0.03% higher, which was within the limits of statistical error. The organic technology ensured the protein content at the level of 25.3%, and the use of the BioStymix-Niva microbial biodegrader - biodestructor contributed to the further growth of the indicator to 25.4%. The oil content of hemp seeds is not limited by other important characteristics, such as the yield of the hemp stems or the fiber content. Only the Glyana variety showed inverse correlations with plant height, hemp stems and seed productivity, they were of medium strength (r = -0.60 – -0.43). In the Zolotoniski 15 variety, only one inverse relationship was recorded, i.e. plant height (r = -0.57). No correlation was established between protein content and oil content in seeds. Correlations may change depending on other factors of cultivation, including weather conditions, elements of technology, etc., but the evaluation of varieties for cultivation according to these characteristics can significantly increase the efficiency of the production of cannabis products.

9

Statistical Analysis of Selected Coal Charateristics and Toxic Compounds for FGX Air-Vibrating Separation

Mijał Waldemar, Niedoba Tomasz, Polek Daria, Baic Ireneusz, Blaschke Wiesław

Inżynieria Mineralna

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2023

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no. 2, vol. 1

377--387

EN

Dry beneficiation methods were popular in the first part of the 20th century. In the 1930s, before World War II, dry separators were used more commonly in the United States. Currently, this method is very popular in China, the United States, India, Russia and other places where its implementation is possible. In Poland, by contrast, dry separation still remains uncommon. However, during the last 30 years, dry separators have started to be more commonly used in coal beneficiation. One example of this type of separator might be the FGX air-vibrating separator. This type of separator uses air suspension to separate heavier particles (tailings) from lighter coal grains. The process of dry separation may depend on various parameters, e.g. particle size fraction, air supply, feed parameters, etc.. This paper describes the mathematical model which shows the scope for using this separation method for coal beneficiation. Mathematical models are based on dependencies between calorific value and ash content in the samples tested as well as relations between arsenic, thallium, mercury, lead and other coal characteristics. The latter parameters are of vital importance as Polish emission standards do not have any limits for the elements mentioned above (arsenic, thallium, mercury and lead).

PL

Suche metody wzbogacania były popularne w pierwszej połowie XX wieku. Separatory suche były używane zwłaszcza przed II Wojną Światową w latach 30-ych w USA. Obecnie, metoda ta jest bardzo popularna w Chinach, USA, Indiach, Rosji oraz w innych miejscach, gdzie możliwe jest jej zastosowanie. W Polsce proces ten jest wciąż bardzo mało popularny. Podczas ostatnich 30 lat systemy wzbogacania węgla zaczęły szerzej korzystać z separatorów suchych a przykładem bardzo popularnego urządzenia tego typu jest FGX – wibracyjny stół powietrzny. Ten typ separatora korzysta z zawiesiny powietrznej w celu wydzielenia cięższych ziaren (odpadów) od lżejszych ziaren węgla. Sucha separacja może zależeć od różnych parametrów, tj. klasa ziarnowa, zasoby powietrza, parametry nadawy itp. Artykuł ten opisuje model matematyczny, który pokazuje możliwości zastosowania tej metody separacji przy wzbogacaniu węgla. Modele matematyczne oparte były na zależnościach pomiędzy wartością opałową oraz zawartością popiołu w testowanych próbkach, jak również na relacjach pomiędzy zawartościami arsenu, talu, rtęci, ołowiu i innych charakterystyk węgla. Ostatnie parametry są bardzo ważne ponieważ polskie standardy emisji nie zawierają limitów dla pierwiastków wymienionych powyżej, a więc arsenu, talu, rtęci oraz ołowiu.

10

Seed Yield and the Possibility of Biofuel Production from Sorghum (Sorghum bicolor L.) in Ukraine

Pravdyva Liudmyla, Prysiazhniuk Oleh, Khakhula Valerii, Fedoruk Yurii, Shushkivska Nataliia

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 5

94--99

EN

The influence of the elements of cultivation technology on the productivity of sorghum (Sorghum bicolor L.) as a feedstock for further processing is gaining relevance. The study was conducted in the Right-Bank Forest-Steppe of Ukraine at the Bila Tserkva Experimental Breeding Station of the Institute of Bioenergy Crops and Sugar Beets in the years 2016–2019. The studied factors were seed and sowings treatment with a growth regulator containing a complex of water-soluble fulvic acids, enzymes, vitamins, and phytohormones. The highest yield of grain (7.1 t/ha), biomass (35.9 t/ha), bioethanol (2.37 t/ha), solid biofuel (11.14 t/ha), and estimated energy output (240.65 GJ/ha) from biomass were obtained in the treatment where both seeds and sowings were treated with a growth regulator. A close relationship between yield and energy performance is found.

11

Pool boiling on horizontal tube, evaluation of ten correlations

Baki Touhami, Sahel Djamel

Archive of Mechanical Engineering

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2023

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LXX, nr 4

481--495

EN

The heat transfer coefficient during the pool boiling on the outside of a horizontal tube can be predicted by correlations. Our choice was based on ten correlations known from the literature. The experimental data were recovered from the recent work, for different fluids used. An evaluation was made of agreement between each of the correlations and the experimental data. The results of the present study firstly showed a good reliability for the correlations of untsov [10], Stephan and Abdeslam [11] with deviations of 20% and 27%, respectively. Also, the results revealed acceptable agreements for the correlations of Kruzhlin [6], Mc Nelly [7] and Touhami [15] with deviations of 26%, 29% and 29% respectively. The remaining correlations showed very high deviations from the experimental data. Finally, improvements have been made in the correlations of Shekriladze [12] and Mostinski [9], and a new correlation was proposed giving convincing results.

12

Defining Irrigation Scheduling Based on Crop Water Stress Index and Physiological Parameters for Hybrid Corn in Semi-Arid Climate

Ucak Ali Beyhan, Saltuk Burak, Rolbiecki Roman, Atilgan Atilgan

Rocznik Ochrona Środowiska

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2022

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Tom 24

231--245

EN

The goal of this study is to determine the crop water stress index (CWSI) and irrigation scheduling based on CWSI values, as well as to examine the correlations between CWSI, physiological parameters and grain yield of hybrid corn P31A34 in semi-arid climate conditions. In 2014 and 2015, the upper limit (UL) temperatures at which plants were entirely exposed to water stress were 1.178°C and 2.38°C, respectively. When the corn grain yield began to decline, the CWSI threshold value was 0.34, indicating the yield limit. Grain yield, crop water consumption, crop water stress index, chlorophyll content, water use efficiency and leaf area index were found to have negative correlations (p ≤ 0.01) with CWSI values in both years of the study. The findings revealed that in semi-arid climate conditions, a maximum of 30% water deficit could be used during the growing period of the corn compared to full irrigation (I100) for water savings and that a water deficit greater than 30% results in considerable grain yield losses. In areas with limited water resources, the moderate water deficit (I70) may be a viable alternative to the I100.

13

Statistical analysis of road freight transport in Catalonia

Boldizsar Adrienn

Production Engineering Archives

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2022

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Vol. 28, Iss. 1

40--49

EN

This article describes the links between economic level, investment in Research & development (R&D), and Catalan freight transport between 2006 and 2016. Catalonia is the second most populous area in Spain, northeast of the Iberian Peninsula, whose economy ranks second among the Autonomous Communities, surpassed only by the Community of Madrid, to speak of a significant economic and social region. The study sought to answer the question of what economic contexts exist in the region regarding freight transport. To do all this, it uses mathematical-statistical tools to explore the relationships between real data sets, which were calculated using seven indicators. The analyses suggest a positive increase in the volume of imports and exports of goods in the region. The same is true for GDP per capita. It came as a surprise that virtually no positive correlations existed between R&D and any other indicators. In analysing the indicators, we found that the current economy was pushed back by the 2008 world economic change, similarly to international trends. At the same time, there has been rapid growth since 2010, especially in exports. This also means that Spain, particularly the Catalan region, has serious trade relations, which affect the region’s economic development and the freight transport industry.

14

Statistical analysis of groundwater quality at Wonji Shoa Sugar Estate

Dinka Megersa Olumana

Journal of Water and Land Development

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2022

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no. 53

45--50

EN

Quality assessment of shallow groundwater table is very important because it is the water that recharges deeper aquifers and constantly feeds the water levels of our surface streams and wetlands. Continuous monitoring of large number of quality parameters is essential for effective maintenance of water quality through appropriate control measures. However, it is very difficult and laborious task for regular monitoring of all the parameters even if adequate manpower and laboratory facilities are available. Therefore, this study presents the statistical analysis of physico-chemical parameters (pH, EC, TDS, Na, K, Ca, Mg, HCO3, Cl, CO3, SO4, TH, B, F) using correlation and Principal Component Analysis. The statistical analysis of the groundwater quality variables indicated that most of the variables are highly correlated. The strong correlation is an opportunity to develop a regression equation and monitor using few parameters. This provides an easy and rapid method of continuous groundwater quality monitoring. Moreover, groundwater of the area showed significant compositional variation. The compositional variability has implications for the source and origin of groundwater quality in the study area.

15

New Construction Methods and Performance Analysis of WINDMI Chaotic System

Salih Thair A.

International Journal of Electronics and Telecommunications

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2022

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Vol. 68, No. 1

129--136

EN

Chaos is an active topic of study in the field of secure communication systems that have garnered much consideration in recent years because of excessive sensitivity to a simple change in its initial conditions. In this paper, the essential features of the suggested WINDMI chaotic system like the phase portraits of the attractors, bifurcation, PSD, correlation, and balance property of the windmi chaotic system have been depicted in detail through MATLAB tools simulations and circuital application. The bifurcation examination detects a wealthy and attractive characteristic of the proposed windmi chaotic oscillator such as periodical multiple bifurcations, has two stable states chaotic demeanor, periodical windows, and recapture bifurcations. In this paper, after exploring the dynamic features of the windmi chaos paradigm, a practical chaotic circuit is implemented on the fpaa chip. Eventually, the circuit practical results of the windmi chaotic attractors present similarities with numerical simulations. The importance of the work is reflected in the use of field programmable analog array in the implementation of the windmi oscillator, and the possibility of varying the initial condition during the operation of the system. An unlimited number of signals can be generated, which enables it to be used as an oscillator utilized in many transceiver systems, that utilized an unlimited number of signals.

16

Analysis of the Correlation Between Crimp Parameters and its Effect on Yarn Strength and Hairiness

Akter Shilpi, Motalab Mohammad Abdul, Helali Maksud

Fibres & Textiles in Eastern Europe

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2022

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Vol. 30, no. 2

55--60

EN

The objective of this paper is to analyse the correlation between crimp parameters and the effect of crimps on yarn strength and hairiness. Crimp is an essential property for natural and man-made fibres. Crimps always form with different parameters as they are very much irregular in size and shape. So, if the crimps are regular in size and shape, the end products like yarn and fabric properties will improve. Jute is a natural fibre with no natural crimp. In this research work, the gear crimping method was used as a mechanical crimping system to impart a regular size and shape of crimps into jute sliver. As a result, crimp parameters like the crimp length and crimp angle become uniform, and it is then easy to measure them. Results also showed that the crimp length is directly proportional and the crimp angle is reversely proportional to the number of crimps per unit length, and they are highly correlated. It was also shown that crimp and crimp parameters also affect the yarn strength and hairiness. In conclusion, it is revealed that with an increase in the number of crimps, the yarn strength was increased and hairiness was decreased.

17

Assessment of the Thermal Decomposition Temperature of High-Energy Heterocyclic Aromatic Compounds in Order to Increase Their Safety during Storage, Handling and Application

Keshavarz Mohammad Hossein, Mousavi Sajjad, Drikvand Masoumeh

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 1

39--62

EN

Heterocyclic aromatic compounds containing various derivatives of five or six-membered nitrogen-containing rings, viz. triazoles, tetrazoles, furazans, triazines, and tetrazines, and some of their salts have been studied. High nitrogen content and a large positive heat of formation are two important properties of these compounds. Two new models are introduced for the reliable prediction of the thermal stability of these compounds through the thermal decomposition temperature (onset). The reported data for 181 compounds have been used to derive and test the new models. For a training set containing 132 heterocyclic aromatic compounds, the values of the average absolute deviation (AAD) and the coefficient of determination (R2) of the improved correlation were 9.72 K and 0.959, respectively. For triazoles, tetrazoles, furazans, triazines, and tetrazines, the predicted results of ADD and R2 for the external test data set for this model containing 41 compounds were 23.03 K and 0.664, respectively, which are closer to experimental data than those obtained by the core correlation, i.e. 26.49 K and 0.653, respectively. The correlation coefficients of cross-validation for leave-one-out (Q2LOO) and 5-fold (Q25CV) of the improved correlation were 0.955 and 0.951, respectively, which confirm that it is not an over-fitted model, robust and well-behaved.

18

Correlation Studies of Dimensional Accuracy with Temperature Changes of Selected Elements of a Machine Tool in the Machining Process

Basara Damian, Skoczylas Leszek

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 1

253--259

EN

The article presents the characteristics of temperature changes of selected components of the machine tool and the temperature of the machining coolant in relation to the selected dimensions of finished parts, such as the AGB gear cover. The tests were carried out on the basis of serial production on the FMS line in a plant producing components for the aviation industry. As part of the research, the machine tool was modernized to the extent that it was possible to register temperatures in real-time. Temperature changes were compared with the dimensions of the machined part in search of dependencies. Correlation calculations between temperature and dimensional data were made with the use of a statistical process control program. Dimensional data were obtained from CMM machines used daily to measure parts from series production.

19

On the detection and attribution of streamflow persistence of rivers in Peninsular India

Adarsh Sankaran, Nourani Vahid, Johnson Ashly, Jayan Anjali, Archana Devarajan Sindhu, Amrutha Asokan Jeeja

Acta Geophysica

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2022

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Vol. 70, no 3

1373--1383

EN

Persistence expressed by hurst exponent (H) is estimated for streamflow of 122 stations in the basins of Peninsular India by three methods at different aggregation scales (daily, monthly mean, monthly and annual maximum). Mean H values indicated long term persistence (LTP) and the data of more than 70% stations showed LTP for other temporal resolutions. H displayed negative correlation with time series length, mean annual and specific mean discharges, while no significant correlation with catchment area. Positive dependence was found between persistence of streamflow and different climatic attributes (rainfall; maximum, mean and minimum temperature) for daily and annual maximum datasets.

20

Environmental monitoring to assess ground water quality and its impact on soils in southwestern India

Sandhu Randhir Singh, Sehgal Simerpreet Kaur, Amrit Kumar, Singh Navdeep, Singh Didar

Acta Geophysica

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2022

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Vol. 70, no 1

349--360

EN

The present study attempts to investigate physicochemical features and evaluate quality of collected ground water samples from benchmark locations in Fazilka district, southwestern (SW) side of the Punjab. The samples of groundwater (GW) as well as soil were collected from different locations and examined for pH, electrical conductivity (EC), carbonates (CO3 2 ), bicarbonates (HCO3 −), chlorides (Cl−), magnesium (Mg2+), calcium (Ca2+), sodium (Na+), sulfate (SO42−) and potassium (K+). The appropriateness of water for drinking was checked using water quality index (WQI), while indices like soluble sodium percentage (SSP), sodium adsorption ratio (SAR), residual sodium carbonate, magnesium hazard, permeability index and Kelly’s ratio were investigated for appraisal of irrigation water quality. Samples are statistically tested using two-way ANOVA and principal component analysis (PCA) to extract correlation between water parameters. Most of the samples were under high to low (C3S1), high to medium (C3S2) and very high to high (C4S3) based on US Salinity Laboratory (USSL). On the base of RSC, samples were under safe to unsuitable category. For hydrochemistry analysis, the piper diagram indicates that water samples were mixed type and Ca-Mg-HCO3 type. Study indicated that water with high salinity was used for irrigation of crops and it has adverse effects on the soil quality and crop yield is of concern for future.