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Abstract

The positive asymptotically stable continuous-time linear systems are approximated by corresponding asymptotically stable discrete-time linear systems. Two methods of the approximation are presented and the comparison of the methods is addressed. The considerations are illustrated by three numerical examples and an example of positive electrical circuit.

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Authors and Affiliations

Tadeusz Kaczorek
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Abstract

The concept of inverse systems for standard and positive linear systems is introduced. Necessary and sufficient conditions for the existence of the positive inverse system for continuous-time and discrete-time linear systems are established. It is shown that: 1) The inverse system of continuous-time linear system is asymptotically stable if and only if the standard system is asymptotically stable. 2) The inverse system of discrete-time linear system is asymptotically stable if and only if the standard system is unstable. 3) The inverse system of continuous-time and discrete-time linear systems are reachable if and only if the standard systems are reachable. The considerations are illustrated by numerical examples.
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Authors and Affiliations

Tadeusz Kaczorek
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Abstract

Necessary and sufficient conditions for robust stability of the positive discrete-time interval system with time-delays are established.

It is shown that this system is robustly stable if and only if one well de?ned positive discrete-time system with time-delays is asymptotically stable. The considerations are illustrated by numerical example.

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Authors and Affiliations

M. Busłowicz
T. Kaczorek
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Abstract

The academic community was and still is a community of scholars taking various positions. Problematic was and still is the changing of ways we set these positions in both, in relation to a long lasting academic tradition and in a much shorter period of academic activity of particular scholars. Some of these ways did show in a greater extent its own usability and some in lesser. In these remarks I make the attempt to point out those who did work out well and in some way still do and which ones should be history by now. However it is not all. Relatively recently ways of positioning of scholars occurred that are in some perspectives innovative and widely applied (also in Poland). Nevertheless they do have in the academic millieu its followers and radical opponents. The bibliometric positioning of scholars is one of those ways.
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Bibliography

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Brzeziński J. (2015), Jeżeli oceniać (jednostki naukowe i badawcze), to JAK oceniać? Przeciwko IF, a za peer review, Nowotwory Journal of Oncology, t. 65, nr 6, s. 476–480.
Crombie A.C. (1960), Nauka średniowieczna i początki nauki nowożytnej, t. II, Warszawa: Instytut Wydawniczy PAX.
Drozdowicz Z. (2017), Stopnie naukowe za wdrożenia, Forum Akademickie 3/2017, s. 30–32.
Einstein A., Infeld L. (1959), Ewolucja fizyki. Rozwój poglądów od najdawniejszych pojęć do teorii względności i kwantów, Warszawa: PWN.
Heller M. (2014), Nowa fizyka i nowa teologia, Kraków: Copernikus Center Press.
Highfield R., Carter P. (1995), Prywatne życie Alberta Einsteina, Warszawa: Prószyński i S-ka.
Hübner P. (2021), Ludzie systemu, Forum Akademickie nr 11.
Le Goff J. (1997), Inteligencja w wiekach średnich, Warszawa: Oficyna Wydawnicza Volumen, Dom Wydawniczy Bellona.
Kierul J. (1996), Izaak Newton. Bóg, światło i świat, Wrocław: Oficyna Wydawnicza Quadrivium.
Kołłątaj H. (1953), Raport z wizytacji Akademii Krakowskiej odbytej w r. 1777, [w:] Wybór pism naukowych, Warszawa: PWN.
Kramer B. (2015). Akademische Ramschwa, Der Spiegel. Archived from the original on 24 June 2018. Retrieved 1 October 2021.
Kulczycki E. (2017), Punktoza jako strategia w grze parametrycznej w Polsce, Nauka i Szkolnictwo Wyższe nr 1(49), s. 63–78.
Marenbon J. (1997). The Philosophy of Peter Abelard, Cambridge: Cambridge University Press.
Mosakowski R. (2002), Szkolnictwo wyższe w krajach Unii Europejskiej. Stan obecny i planowane reformy, Gdańsk: Wydawnictwo Politechniki Gdańskiej.
Noble K.A. (1994), Changing Doctoral Degrees: an International Perspective, Buckingham, Bristol: Society for Research into Higher Education: Open University Press.
Jamblich (1993), O życiu pitagorejskim, Wrocław: Epsilon.
Popper K.R. (2006), Społeczeństwo otwarte i jego wrogowie, t. 2, Warszawa: Wydawnictwo Naukowe PWN.
Porfiriusz (1993), Żywot Pitagorasa, Wrocław: Epsilon.
Roemer R.Ch, Borchard R. (2015), Meanigful Metrics, Chicago, Illinois: The Association of College & Research Libraries, a division of the American Library Association.
Skoble A.J. (2019), Tenure: The Good Outweighs the Bad – A Surresponse to James E. Bruce, Journal of Markets & Morality, t. 22, nr 1: 207–210.
Structure of the U.S. Education System: Research Doctorate Degrees. U.S. Department of Education. Archived from the original on 27 January 2012. Retrieved 1 October 2021.
Towpik E. (2015), IF-mania: Journal Impact Factor jest właściwym wskaźnikiem oceniania wyników badań naukowych, indywidualnych uczonych ani ośrodków badawczych, Nowotwory Journal of Oncology, t. 65, nr 6, s. 465–475.
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Walicki A. (2014), Odpowiedź na ankietę „Przeglądu Filozoficznego”, Przegląd Filozoficzny – Nowa Seria nr 1 (89).
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White M., Gribbin J. (1998), Darwin. Żywot uczonego, Warszawa: Prószyński i S-ka.
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Authors and Affiliations

Zbigniew Drozdowicz
1
ORCID: ORCID

  1. Instytut Kulturoznawstwa, Uniwersytet im. Adama Mickiewicza, Poznań
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Abstract

2D position error in the Global Positioning System (GPS) depends on the Horizontal Dilution of Precision (HDOP) and User Equivalent Range Error UERE. The non-dimensional HDOP coefficient, determining the influence of satellite distribution on the positioning accuracy, can be calculated exactly for a given moment in time. However, the UERE value is a magnitude variable in time, especially due to errors in radio propagation (ionosphere and troposphere effects) and it cannot be precisely predicted. The variability of the UERE causes the actual measurements (despite an exact theoretical mathematical correlation between the HDOP value and the position error) to indicate that position errors differ for the same HDOP value.
The aim of this article is to determine the relation between the GPS position error and the HDOP value. It is possible only statistically, based on an analysis of an exceptionally large measurement sample. To this end, measurement results of a 10-day GPS measurement campaign (900,000 fixes) have been used. For HDOP values (in the range of 0.6–1.8), position errors were recorded and analysed to determine the statistical distribution of GPS position errors corresponding to various HDOP values.
The experimental study and statistical analyses showed that the most common HDOP values in the GPS system are magnitudes of: 0.7 (�� = 0•353) and 0.8 (�� = 0•432). Only 2.77% of fixes indicated an HDOP value larger than 1. Moreover, 95% of measurements featured a geometric coefficient of 0.973 – this is why it can be assumed that in optimal conditions (without local terrain obstacles), the GPS system is capable of providing values of HDOP ≤ 1, with a probability greater than 95% (2��). Obtaining a low HDOP value, which results in a low GPS position error value, calls for providing a high mean number of satellites (12 or more) and low variability in their number.
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Authors and Affiliations

Mariusz Specht
1

  1. Department of Transport and Logistics, Gdynia Maritime University, Morska 81-87, 81-225 Gdynia, Poland
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Abstract

Accurate prediction of blasting vibration should be achieved in mine blasting production practice. It is also a critical problem in the field of blasting vibration control technology research. In this research paper, on the basis of the previous research results and taking account into the reflection principle of elastic wave at the free interface, the authours proposes the blasting seismic wave propagation model. In addition, the blasting positive elevation effect are theoretically explained in detail, and the vibration velocity prediction formula of the positive elevation effect is derived. Finally, the positive elevation effect mechanism and the step (positive) formula are calibrated based on the on-site monitoring data of blasting vibration of Qipanjing Jinou coal mine. In beirf, a theoretical basis is laid by this paper for similar blasting projects.
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Authors and Affiliations

X.J. Zhang
1
H.M. An
2

  1. School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
  2. Kunming University of Science and Technology, Faculty of Public Security and Emergency Management, 650093, Kunming, China
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Abstract

In this work, a novel perspective is proposed to develop schematics solutions for electro-hydraulic positioning actuators. The basis of the design approach has been established, which includes: a set of possible desired properties of actuators; a series of defined typical positioning methods; variants of schematic structures; a quantitative assessment method for specific properties based on influencing factors; the quantitative relationship between the structure and properties of actuators, as well as the method for overall evaluation of the actuator's performance based on the total score. The results obtained can serve as the basis for an effective design approach, which allows for reducing the number of iteration cycles while developing new electro-hydraulic positioning actuator schematic solutions.
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Authors and Affiliations

Qiang Li
1
ORCID: ORCID
Oleksandr Uzunov
1
ORCID: ORCID

  1. Department of Fluid Mechanics and Mechatronics, National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine
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Abstract

This paper reviews the key studies concerning GNSS positioning and applications conducted at leading Polish research institutions from 2019 until 2022. The review also constitutes a contribution to the national report of Poland for the International Union of Geodesy and Geodynamics (IUGG) presented at the 28th General Assembly of IUGG held in 2023 in Berlin, Germany. In particular, we discuss the advances in theory and applications of relative and absolute positioning, troposphere and ionosphere sounding, smartphone and low-cost GNSS data processing, and other specific studies such as those on satellite antenna calibration and clock stability. In light of these recent advances by the Polish scientific community, continuous progress in GNSS theory and processing algorithms is thought to be maintained in the future, and GNSS applications are expected to continue to proliferate.
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Authors and Affiliations

Jacek Paziewski
1
ORCID: ORCID
Tomasz Hadas
2
ORCID: ORCID
Witold Rohm
2
ORCID: ORCID
Paweł Wielgosz
1
ORCID: ORCID

  1. University of Warmia and Mazury, Olsztyn, Poland
  2. Wroclaw University of Environmental and Life Sciences, Wroclaw, Poland
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Abstract

The present study aimed to test how common workaholism is and which groups are most targeted in the workplace among Jordanian employees. Additionally, the roles of positive and negative perfectionism in workaholism were investigated. The sample consisted of 686 employees. All of them completed the study instruments. The results showed that the mean of workaholism was around the mean of the cut -off. Additionally, multivariate tests showed that the results of post hoc differences for positive perfectionism were in favor of males, subordinates, those with a bachelor’s degree, those with less than 5 years of experience, and those aged less than 30 years. Furthermore, the differences for negative perfectionism were in favor of those with a bachelor’s degree and subordinates. For workaholism, the differences were in favor of subordinates, public sector employees, married persons, and those with a diploma degree. Finally, the results of hierarchical regression analysis found that positive and negative perfectionism and some demographic variables predicted 12.9% of the variability in workaholism, and the typical hierarchical regression model included positive and negative perfectionism without other demographic variables.

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Authors and Affiliations

Basim Aldahadha
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Abstract

A method of determination of drive functions of slewing of a mobile crane's upper structure is presented in the paper. The purpose of their determination is to reduce load oscillations at the end of the motion. Drive functions for selected angles and durations of slewing have been calculated using a simple model of the crane and dynamic optimisation. Drive functions for intermediate angles have been determined by means of interpolation. Res ul ts of numerical simulations executed for the model of the crane are presented, taking into consideration flexibilities and damping in the cranes subsystems. Results obtained for drive functions determined using optimisation and interpolation algorithms are compared. An attempt to determine sensitivity of load positioning to selected operating parameters is also presented. Introduction of the notion of a positioning quality coefficient is proposed.
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Authors and Affiliations

Andrzej Maczyński
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Abstract

The term positive psychology has recently entered the field of Second Language Acquisition. The article explains the meaning of the term, presents the definitions of positive psychology, its objectives and history. The key part of the article demonstrates the importance of positive psychology in the second language acquisition presenting many connections between the two fields. The author recommends that positive education is introduced in every school and every foreign language classroom.

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Authors and Affiliations

Katarzyna Budzińska
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Abstract

I investigate the idea of science elaborated by Edmund Husserl in his later works, first of all, in Cartesian Meditations and the Crisis of European Sciences. The first part of this investigation has been published in the paper: Edmunda Husserla idea nauki i projekt fenomenologii jako nauki ścisłej [Edmund Husserl’s Idea of Science and the Project of Phenomenology as a Strict Science], Filozofia i nauka. Studia filozoficzne i interdyscyplinarne, 2019, 7 (2), pp. 247–264. Husserl claims that the transformation of philosophy into a strict science, which is the basic aim of his intellectual enterprise, is connected with a reform of all the positive sciences. Positive science is closely related to philosophy—both they have a common grounding and ideal. The paper also compares Husserl’s project of philosophy as a fundamental science with the today trends in philosophy and the plurality of its schools, attitudes, fields of problems and methods.

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Authors and Affiliations

Małgorzata Czarnocka
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Abstract

This study analyses the performances of various path controlling strategies for a 3-degrees of freedom wrist exoskeleton, by comparing key indicators, such as rise time, steady-state error, and implementation difficulty. A model was built to describe both system’s kinematics and dynamics, as well as 3 different controllers (PID, PD¸, and a hybrid force/position controller) that were designed to allow each joint to perform smooth motions within anatomic ranges. The corresponding simulation was run and assessed via Matlab (version 2020a). In addition to the performance comparison, remarkable characteristics could be identified among controllers. PD¸ showed higher response speed than the other controllers (about 4 times), and PID was reinforced as the technique with the easiest implementation due to the smallest matrices. The study also allowed to greater potential of the hybrid controller to interact with its environment, i.e., the robotic device.
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Authors and Affiliations

Valeria Avilés
1
Oscar F. Avilés
1
Jorge Aponte
1
Oscar I. Caldas
1
Mauricio F. Mauledoux
1

  1. Davinci Research Group, Mechatronics Engineering, Militar Nueva Granada University, Cr 11 No 101-80, Bogotá, Colombia
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Abstract

The possibilities to improve values of the satellite orbit elements by employing the pseudo-ranges and differences of carrier phase frequencies measured at many reference GPS stations are analysed. An improvement of orbit ephemeris is achieved by solving an equation system of corrections of the pseudo-ranges and phase differences with the least-squares method. Also, equations of space coordinates of satellite orbit points expressed by ephemeris at fixed moments are used. The relation between the accuracy of the pseudo-ranges and phase differences and the accuracy of the satellite ephemeris is analysed. Formulae for estimation of the influence of the ephemeris on the measured pseudo-ranges and phase differences and for prediction of the accuracy of the pseudo-ranges and phase differences were obtained. An influence of the covariance between single orbit parameters on the accuracy of the pseudo-ranges and phase differences is detected.

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Authors and Affiliations

Jonas Skeivalas
Eimuntas Paršeliūnas
Raimundas Putrimas
Dominykas Šlikas
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Abstract

The global stability of positive continuous-time standard and fractional order nonlinear feedback systems is investigated. New sufficient conditions for the global stability of these classes of positive nonlinear systems are established. The effectiveness of these new stability conditions is demonstrated on simple examples of positive nonlinear systems.

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Authors and Affiliations

T. Kaczorek
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Abstract

The global stability of discrete-time nonlinear systems with descriptor positive linear parts and positive scalar feedbacks is addressed. Sufficient conditions for the global stability of standard and fractional nonlinear systems are established. The effectiveness of these conditions is illustrated on numerical examples.

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Authors and Affiliations

Tadeusz Kaczorek
ORCID: ORCID
Andrzej Ruszewski
ORCID: ORCID
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Abstract

I investigate Husserl’s long-term research on revealing/constructing a proper idea of science. For Husserl this idea was of tremendous importance: it had to be the basis of forming a (the) proper philosophy (phenomenology), that is, a philosophy which was to be an exact science, a new and higher form of science. According to Husserl, the idea of science is not a free project of individual researchers, scientific communities, but the very essence of science—changeless, universal, nontransformable, non-culturally and socially loaded, ahistorical, and non-relativized to scientific praxis. It was attempt to determine a new status of philosophy which led Husserl’s to the consideration of a universal idea of science.

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Authors and Affiliations

Małgorzata Czarnocka
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Abstract

The issues discussed in the study mainly relate to the costs presented by the structure of positions. This study, on the example of the KGHM Polska Miedź SA mining company (three mining plants), examines the position and cost calculation structure relating to technological works, cost settlement and receivables between branches and mining plants. Cost comparisons were also carried out from the perspective of the organizational structure. The cost centers, registration and settlement of costs in the accounting records, i.e. SAPR3 were highlighted. In the course of the examination, a comparative analysis was carried out aimed at determination of common features and differences between the cost of technological works by their function in the technical cost of manufacturing. As a result of the analysis, it was determined that in the years 2000–2017, the cost structure based on the position function underwent changes. The changes occurred as a result of organizational and technical and geological and mining conditions. The cost analysis allows to identify the directions of specialization of the entity in the future. The basic operating activity of the mines concentrates on extraction. Due to copper extraction in the concession areas, the analysis was to evaluate the costs incurred in the KGHM Polska Miedź SA mining plants.

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Authors and Affiliations

Anna Bajus
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Abstract

The article is an attempt to analyze the spatio-pedagogical discourse of the German social pedagogy. It represents only a fragment of reflection on the turns in paradigm of place/ space (spatial turn), as pedagogical terms. & e authors seek to answer the question what is the space and place, and what concepts in the field of reflection on the place/space run in the German social pedagogy. The text introduces, inter alia, the relational concept of space developed by Martina Löw, duality of space and the concept of spacing. Active creation of urban space, the spatial dimension of the relationship and its dynamics are subjected to discussion. The article presents critical approach to the notion of transdisciplinary space, and space-oriented social work. Finally, it provides the incentive for in-depth, international analyzes of spatio-pedagogical theories.

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Authors and Affiliations

Jacqueline Puchert
Aleksandra Kurowska-Susdorf
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Abstract

This paper presents integration of ultrasonic and inertial approaches in indoor navigation system. Ultrasonic navigation systems allow to obtain good results whilst there are at least three beacon transmitters in the range of mobile receiver, but in many situations placement of large number of transmitters is not economically justified. In such situations navigation must be aided by other technique. This paper describes research on supporting ultrasonic system by inertial system based on Magnetic, Angular Rate and Gravity sensor. This can measure current orientation of the receiver and allows to estimate the length of the path by pedometer functionality.

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Authors and Affiliations

Krzysztof Tokarz
Piotr Czekalski
Wojciech Sieczkowski
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Abstract

There is a growing body of research investigating the relationships among gratitude, self-esteem, and subjective well-being. However, there remains a scarcity of research examining the impact of self-esteem on the relationship between gratitude and subjective well-being within Arabic context. In this study, 300 Arabic speaking adults completed measurements of gratitude, self-esteem, satisfaction with life, and positive and negative experiences. Participants’ ages ranged between 18 and 54 years with a mean age of 29.67 years (SD = 8.91). The correlation results revealed that there were significant positive relationships between gratitude, self-esteem, satisfaction with life, and positive experience, while there were significant negative relationships between gratitude, self-esteem, satisfaction with life, and negative experience. The results also showed that gratitude and self-esteem directly predicted subjective well-being. Additionally, using structural equation modeling, self-esteem exerted a mediation effect on the relationship between gratitude and subjective well-being. The results suggest that enhancing self-esteem could assist adults who have gratitude to experience greater subjective well-being. Using the source of self-esteem, researchers and professionals could improve one’s subjective wellbeing by employing various gratitude activities.

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Authors and Affiliations

Murat Yildirim
Nouf Abdullah Alshehri
Izaddin Ahmad Aziz
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Abstract

In the paper positive fractional continuous-time linear systems are considered. Positive fractional systems without delays and positive fractional systems with a single delay in control are studied. New criteria for approximate and exact controllability of systems without delays as well as a relative controllability criterion of systems with delay are established and proved. Numerical examples are presented for different controllability criteria. A practical application is proposed.
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Bibliography

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Authors and Affiliations

Beata Sikora
1
ORCID: ORCID
Nikola Matlok
1

  1. Department of Applied Mathematics, Silesian University of Technology, Kaszubska 23, 44-100 Gliwice, Poland
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Abstract

Position time series from permanent Global Navigation Satellite System (GNSS) stations are commonly used for estimating secular velocities of discrete points on the Earth’s surface. An understanding of background noise in the GNSS position time series is essential to obtain realistic estimates of velocity uncertainties. The current study focuses on the investigation of background noise in position time series obtained from thirteen permanent GNSS stations located in Nepal Himalaya using the spectral analysis method. The power spectrum of the GNSS position time series has been estimated using the Lomb–Scargle method. The iterative nonlinear Levenberg–Marquardt (LM) algorithm has been applied to estimate the spectral index of the power spectrum. The power spectrum can be described by white noise in the high frequency zone and power law noise in the lower frequency zone. The mean and the standard deviation of the estimated spectral indices are −1.46±0.14,−1.39±0.16 and −1.53±0.07 for north, east and vertical components, respectively. On average, the power law noise extends up to a period of ca. 21 days. For a shorter period, i.e. less than ca. 21 days, the spectra are white. The spectral index corresponding to random walk noise (ca. –2) is obtained for a site located above the base of a seismogenic zone which can be due to the combined effect of tectonic and nontectonic factors rather than a spurious monumental motion. Overall, the usefulness of investigating the background noise in the GNSS position time series is discussed.

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Authors and Affiliations

Jagat Dwipendra Ray
M. Sithartha Muthu Vijayan
Walyeldeen Godah
ORCID: ORCID
Ashok Kumar
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Abstract

The article is devoted to the study of the national worldview’s peculiarities on the material of names of airspace, celestial bodies and natural elements. The quantitative analysis of common and different meanings of the analyzed lexical units in Ukrainian, German, English and French relating to the person’s characteristics in society is carried out. The greatest number of connotative meanings that characterize the behavior, features of character, appearance and a certain state of a person, show the lexemes water and fire. The lower item takes the use of the lexeme moon, and the lexemes sky and sun are in the last positions. Among the common and different meanings the common meanings prevail quantitatively. In the different meanings with national peculiarity the most belong to French. The use of each of the analyzed names in figurative meanings reveals the meanings with a positive and negative connotation, the meanings with negative connotation prevail. The obtained results are indicative of the importance of the analyzed names for different peoples.
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Authors and Affiliations

Larysa Drobakha
1

  1. Vinnytsia Mykhailo Kotsiubynskyi State Pedagogical University

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