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Abstract

Bertrand Russell is known primarily as a logician, philosopher of mathematics, and analytical philosopher. However, a significant part of his life was devoted to world peace: he was an active pacifist from 1901 until his death. This article shows him in this role. Russell’s pacifist activities included not only participation in demonstrations and organizations, but also educational activities. He dealt with issues of education as a theorist and a practitioner. He organized his educational endeavour round the question of how to educate a pacifist and at the same time help her/him remain a free and creative woman/man.
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Authors and Affiliations

Magdalena Środa
1
ORCID: ORCID

  1. Uniwersytet Warszawski, Wydział Filozofii, ul. Krakowskie Przedmieście 3, 00-927 Warszawa
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Abstract

RADAR plays a vital role in military applications since its origin in the 2nd world war. Recently it has been used in surface inception, health monitoring, infrastructure health monitoring, etc. In these applications, Ultra-wideband RADAR systems are more popular than traditional RADAR systems. Impulse RADAR is a special kind of ultra-wideband RADAR, which is mostly used for surface penetration, through-wall imaging, antimissile detection, anti-stealth technology, etc. because of its high resolution and low center frequency. Out of all these applications, impulse RADAR has been used intensively as a ground-penetrating RADAR for the detection of land mines, underlying pipelines, buried objects, etc. This report has attempted to provide the steps for designing the impulse ground penetrating RADAR (GPR) as well as provides the value of crucial parameters required in the design process of commercial GPR systems.
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Bibliography

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[5] M. Sato, “Principles of mine detection by ground-penetrating RADAR,”Anti-personnel Landmine Detection for Humanitarian Demining, Springer London, 2009. 19-26. DOI: https://doi.org/10.1007/978-1-84882-346-4_2.
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[7] J. S. Lee and C. Nguyen, “Novel low-cost ultra-wideband, ultra-short-pulse transmitter with MESFET impulse-shaping circuitry for reduced distortion and improved pulse repetition rate,” IEEE Microwave Wireless Compon. Lett. , vol.11, pp. 208 -210, 2001. DOI: https://doi.org/10.1109/7260.923030.
[8] J. S. Lee and C. Nguyen, “Uniplanar picosecond pulse generator using step-recovery diode,” Electron. Lett., vol. 37, pp. 504–506, 2001. DOI: https://doi.org/10.1049/el:20010350
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[11] Yan Xiao, Zhong-Yong Wang, Li, J., Zi-Lun Yuan , “Design of a Second-Derivative Gaussian pulse generator,” IEEE International Conference on Signal Processing, Communication and Computing (ICSPCC), pp. 1 – 4, 2013. DOI: https://doi.org/10.1109/ICSPCC.2013.6663994.
[12] M.S. Nikoo, S.M.A. Hashemi., “High-Power Nanosecond Pulse Generator With High-Voltage SRD and GDT Switch,” IEEE Trans. Plasma Sci. ,vol. 43, no. 9, pp. 3268-3276, Sept. 2015. DOI: https://doi.org/10.1109/TPS.2015.2411251.
[13] M. Cavallaro, E. Ragonese and G. Palmisano, “An ultra-wideband transmitter based on a new pulse generator,” Proc. IEEE Radio Freq. Integ. Circuits Symp, pp. 43-46, 2008. DOI: https://doi.org/10.1109/RFIC.2008.4561382.
[14] El-Gabaly, “Pulsed RF Circuits for Ultra Wideband Communications and RADAR Applications,” Ph.D dissertation, Dept. Elect. Comput. Eng., Queen’s University, Canada, Aug. 2011.
[15] S. Bourdel et. al., “A 9-Pj/Pulse 1.42-Vpp OOK CMOS UWB pulse generator for the 3.1-10.6-GHz FCC band,” IEEE Trans. Microw. Theory Tech., vol. 58, no. 1, pp. 65, 2010. DOI: https://doi.org/10.1109/TMTT.2009.2035959.
[16] Aitykul Omurzakov, Ahmet K. Keskin., “Avalanche Transistor Short Pulse Generator Trials for GPR,” 2016 8th International Conference on Ultra wideband and Ultra short Impulse Signals), Dec. 2016. DOI: https://doi.org/10.1109/UWBUSIS.2016.7724188.
[17] Ran Zhang, Lai-Liang Song., “Research on narrow pulse generation for ultra-wideband communication,” 2016 13th International Computer Conference on Wavelet Active Media Technology and Information Processing (ICCWAMTIP), Dec. 2016. DOI: https://doi.org/10.1109/ICCWAMTIP.2016.8079860.
[18] S. Sim, D. Kim and S. Hong, “A CMOS UWB Pulse Generator for 6–10 GHz Applications,” IEEE Microwave and Wireless Components Letters, vol. 19, no. 2, pp. 83-85, Feb. 2009, DOI: https://doi.org/10.1109/LMWC.2008.2011318.
[19] K. Zhou, C. L. Huang and M. Lu, “A nanosecond pulse generator based on avalanche transistor,” 2016 16th International Conference on Ground Penetrating Radar (GPR), Hong Kong, 2016, pp. 1-5, DOI: https://doi.org/10.1109/ICGPR.2016.7572649.
[20] P. Protiva, J. Mrkvica, and J. Macháč, “A compact step recovery diode subnanosecond pulse generator,” Microw. Opt. Technol. Lett., 52: 438-440. DOI: https://doi.org/10.1002/mop.24945 .
[21] T.P. Montoya, G.S. Smith, “A study of pulse radiation from several broad-band loaded monopoles,” IEEE Trans. Antennas Propag., vol. 44, no. 8, pp. 1172-1182, Aug 1996. DOI: https://doi.org/10.1109/8.511827.
[22] David J. Daniels, Ground Penetrating RADAR, 2nd Edition, IET, 2005. DOI: https://doi.org/10.1049/PBRA015E.
[23] S. Vitebskiy, L. Carin, M. A. Ressler and F. H. Le, “Ultra-wideband, short-pulse ground-penetrating radar: simulation and measurement,” IEEE Transactions on Geoscience and Remote Sensing, vol. 35, no. 3, pp. 762-772, May 1997, DOI: https://doi.org/10.1109/36.581999.
[24] M.A. Gonzalez-Huici, U. Uschkerat, V. Seidel, C. Pedlow, “A preliminary study of the radiation characteristic of an experimental GPR antenna for underground cavity detection,” IEEE International Conference on Microwaves, Communications, Antennas and Electronics Systems (COMCAS), 2011, pp. 1-5, 7-9 Nov 2011. DOI: https://doi.org/10.1109/COMCAS.2011.6105908.
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[28] M. Yan, M. Tian, L. Gan and X. Chen, “Impulse Ground Penetrating Radar Hardware System Design,” 2006 6th International Conference on ITS Telecommunications, Chengdu, 2006, pp. 1244-1247, DOI: https://doi.org/10.1109/ITST.2006.288852.
[29] A.P. Annan, L.T. Chua, “Ground penetrating RADAR performance predictions,” Ground penetrating RADAR, ed. J. Pilon; Geological Survey of Canada, Paper 90-4, pp. 5-13, 1992.
[30] Jeong Soo Lee, Cam Nguyen and T. Scullion, “A novel, compact, low-cost, impulse ground-penetrating radar for nondestructive evaluation of pavements,” IEEE Transactions on Instrumentation and Measurement, vol. 53, no. 6, pp. 1502-1509, Dec. 2004, DOI: https://doi.org/10.1109/TIM.2004.82730.
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Authors and Affiliations

Saket Kumar
1
Amit Kumar
2
Vikrant Singh
3
Abhishek Kumar Singh
4

  1. Department of Electronics and Communication Engineering, Muzaffarpur Institute of Technology, Muzaffarpur, Bihar, India
  2. Department of Electronics and Communication Engineering, Bharati Vidyapeeth (Deemed to be University) College of Engineering, Pune, India
  3. Department of Electrical and Electronics Engineering, IIT Guwahati, India
  4. School of Advanced Sciences, Department of Physics, Vellore Institute of Technology, Vellore, Tamil Naidu, India
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Abstract

Influence of magnetic field on parameters of normal detonation wave and cumulation process of cylindrical detonation wave in gaseous explosive mixture was examined. A review of applications of generalised Chester-Chisnell-Whitham (CCW) method used for analysis of implosion processes of detonation waves is presented.
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Authors and Affiliations

Jerzy Tyl
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Abstract

Self-control is a complex and multifaceted construct that can be regarded as an individual trait that follows its own developmental trajectory. In the presented study we used NAS-50 for the assessment of self-control in adolescents and young adults. Since the questionnaire has not been used before in underage participants we tested its reliability in adolescent and adult samples. We also investigated possible age and gender differences in self-control abilities as well as relations between NAS-50 and behavioral measures of cognitive control and impulsivity. Although the sample was quite small, the reliability of the questionnaire was similar to the results achieved by its authors. According to the predictions in the literature we did not find relations between NAS-50 and behavioral measures of cognitive control and impulsivity. We also did not observe significant age differences in the assessment of self-control abilities. The theoretical relevance of our results is discussed.

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Authors and Affiliations

Joanna Fryt
Tomasz Smoleń
Karolina Czernecka
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Abstract

Most satellites stationed in space use catalytic propulsion systems for attitude control and orbit adjustment. Hydrazine is consumed extensively as liquid monopropellant, in the thrusters. Catalytic reactor is the most important section in the catalytic thruster. Ammonia and nitrogen gases are produced as a result of complete catalytic decomposition of hydrazine in the reactor, causing an increase in temperature and a rise in specific impulse. Ammonia is subsequently decomposed, leading to nitrogen and hydrogen gases. Decomposition of ammonia leads to a decrease in temperature, molecular weight and specific impulse. The latter phenomenon is unavoidable. The effect of ammonia decomposition on the reactor temperature, molecular weight of gaseous products and conclusively on specific impulse was studied in this article. At adiabatic state, thermodynamic analysis revealed that the maximum and minimum temperatures were 1655 K and 773 K, respectively. The highest molecular weight was obtained at ammonia conversion of zero and the lowest when ammonia conversion was 100%. The maximum specific impulse (305.4 S) was obtained at ammonia conversion of zero and completely conversion of ammonia, the minimum specific impulse (about 213.7 s) was obtained. For specific impulse, the result of thermodynamic calculation in this work was validated by the empirical results.

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Authors and Affiliations

Shahram Pakdehi
Fatemeh Shirvani
Reihaneh Zolfaghari
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Abstract

This article deals with the analysis of the fractal dimension of streamers propagating in mineral oil, under lightning impulse voltage, using the box counting method; the method and technique of calculation are described therein. In the considered experimental conditions, the average velocities of recorded streamers are of 2.4 km/s and 1.8 km/s for positive and negative streamers, respectively; these velocities correspond to the 2nd mode of streamers propagation. It is shown that the streamers present the fractal dimension D ; and the higher D is the bushier are the streamers (i.e. with high branch density). The positive streamers can have higher D than the negative ones, if they are bushier.
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Bibliography

[1] Abu Shehab W.F., Ali S.A., Alsharari M.I., Lightning protection for power transformers of Aqaba Thermal Power Station, Archives of Electrical Engineering, vol. 69, no. 3, pp. 645–660 (2020), DOI: 10.24425/aee.2020.133923.
[2] Devins J.C., Rzad S.J., Schwabe R.J., Breakdown and pre-breakdown phenomena in liquids, Journal of Applied Physiscs, vol. 52, pp. 4531–4545 (1981), DOI: 10.1063/1.329327.
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[7] Lesaint O., Prebreakdown phenomena in liquids: propagation “modes” and basic physical properties, Journal of Physics D-Applied Physics, vol. 49, no. 14, 22 (2016), DOI: 10.1088/0022- 3727/49/14/144001.
[8] Rozga P., Beroual A., Przybylek P., Jaroszewski M., Strzelecki K., A Review on Synthetic Ester Liquids for Transformer Applications, Energies, vol. 13, 6429 (2020), DOI: 10.3390/en13236429.
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[13] Ficker T., Electrostatic discharges and multi-fractal analysis of their Lichtenberg figures, Journal of Physiscs D: Applied Physics, vol. 32, pp. 219–226 (1999).
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Authors and Affiliations

Viet-Hung Dang
1
ORCID: ORCID
Abderrahmane Beroual
2
ORCID: ORCID
Pawel Rozga
3
ORCID: ORCID

  1. Electric Power University, Vietnam
  2. University of Lyon, Ecole Centrale de Lyon, France
  3. Lodz University of Technology, Poland
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Abstract

The electrostatic impulse method is an established method for producing microbeads or capsules. Such particles have found application in biomedical engineering and biotechnology. The geometric properties of the droplets – constituting precursors of microbeads and capsules – can be precisely controlled by adjusting the geometry of the nozzle system, the physical properties and the flow rate of the fluids involved, as well as the parameters of the electrostatic impulse. In this work, a method of mathematical modeling of the droplet generation process using the electrostatic impulse method in a single nozzle system is presented. The developed mathematical model is an extension of the standard Volume of Fluid (VOF) model by addition of the effect of the electric field on the fluid flow. The model was implemented into the OpenFOAM toolkit for computational fluid dynamics (CFD). The performed CFD simulation results showed good agreement with experimental data. As a result, the influence of all process parameters on the droplet generation process was studied. The most significant change in droplet generation was caused by changing the electrostatic impulse strength. The presented modeling method can be used for optimization of process design and for studying the mechanisms of droplet generation. It can be extended to describe multi nozzle systems used for one-step microcapsule production.
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Authors and Affiliations

Piotr Cendrowski
1
ORCID: ORCID
Katarzyna Kramek-Romanowska
1
ORCID: ORCID
Dorota Lewińska
2
ORCID: ORCID
Marcin Grzeczkowicz
2
ORCID: ORCID
Paulina Korycka
3
ORCID: ORCID
Jan Krzysztoforski
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, ul. Ludwika Warynskiego 1, Warsaw, Poland
  2. Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, ul. Ks. Trojdena 4, Warsaw, Poland
  3. Foundation of Research and Science Development, Rydygiera 8, 01-793 Warsaw, Poland
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Abstract

The paper presents an analytical solution of levitation problem for conductive, dielectric and magnetically anisotropic ball. The levitation exerts either an AC or impulse magnetic field. Both the Lorentz and material electromagnetic forces (of magnetic matter) could lift the ball in a gravitational field. The electromagnetic field distribution is derived by means of variables separation method. The total force is evaluated by Maxwell stress tensor (generalized), co-energy and Lorentz methods. Additionally, power losses are calculated by means of Joule density and the Poynting vector surface integrals. High frequency asymptotic formulas for the Lorentz force and power losses are presented. All analytical solutions derived could be useful for rapid analysis and design of levitations systems. Finally, some remarks about considered levitations are formulated.
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Bibliography

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  17.  D. Spałek, “Levitation of Conductive and Magnetically Anisotropic Ball”, IEEE Trans. Magn. 55 (3), 1000406 (2019).
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Authors and Affiliations

Dariusz Spałek
1
ORCID: ORCID

  1. Silesian University of Technology, Electrical Engineering Faculty, ul. Akademicka 10, 44-100 Gliwice, Poland
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Abstract

The symbolistic poetry of Alexander Blok is connected with the thinking of both philosophers and psychoanalysts about the world and the man inscribed in it by the phenomenon of “I”. When coming into contact with transcendence, the poet crosses the demarcation line dividing the rational and irrational world, consciousness and unconsciousness. In the first period of creativity, the Russian symbolist nourishes his imagination, infl uenced by the philosophy of Vladimir Soloviev, with longing for the ideal of femininity. The driving force of the Blok’s imagination becomes, understood after Freud, the desire to meet the ideal residing in the oneiric space, and then to unite with it at the dual level (physical and spiritual). From the psychoanalytic perspective, the cycle Verses about the Beautiful Lady is both an attempt to go beyond awareness and search for the sense of a poetic image, its original source in the unconscious, as well as entering into the mirror phase described by J. Lacan. Beautiful Lady plays a role of what the French psychiatrist appoints as an objet petit a: this object is essentially unreachable and that is why it raises a great desire in the lyrical subject. The mechanism of the transition from chaos to unity, though only apparent in Blok’s works, is identical to the psycho-physical experience of the child, observing himself in the mirror.

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Authors and Affiliations

Izabella Malej
ORCID: ORCID
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Abstract

The results of a systematic study of the influence of meridional contours overlap in the stator-rotor axial interspace of the impulse and reactive type stages of a high-pressure steam turbine on the flow structure and gas-dynamic efficiency of the flow part are introduced. The studied flow parts of the impulse and reactive stages are typical for high-power high-pressure steam turbines. It is shown that the stages that have no overlaps and/or have a smooth shape of meridional contours have the best gasdynamic efficiency, and the most negative effect on the flow part is caused by the presence of caverns in the stator-rotor interspace. For cases where, due to technological limitations, it is impossible to avoid the presence of caverns and overlaps with a sharp (step-wise) change in the shape of the meridional contours, it is recommended to perform overlaps with positive size of overlap values near the rotor blades.
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Bibliography

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[5] Lee J.F.: Theory and Design of Steam and Gas Turbines. McGraw-Hill, London 1999.
[6] Oprea I., Negreanu G.: Research on the long blades of the steam turbine. In: Proc. Conf.: METIME 2005, 2005.
[7] Stodola A.: The Steam Turbine and the Future of Heat Engines. St. Petersburg 1904 (in Russian).
[8] Shcheglyaev A.V.: Steam turbines. Thermal Process Theory and Turbine Construction. Vol. 2, (6th Edn.). Energoatomizdat, Moscow 1993 (in Russian).
[9] Kazandzhan P.K., Tikhonov N.D.: Theory of Aircraft Engines. The Theory of Blade Machines: Part 1. Mechanical Engineering, Moscow 1995 (in Russian).
[10] Kostyuk A.G.: Some pressing problems of design and modernization of steam turbines. Therm. Power Eng. 4(2005), 16–27 (in Russian).
[11] Ainley D.G.; Mathieson C.R.: An Examination of the Flow and Pressure Losses in Blade Rows of Axial-Flow Turbines. Aeronaut. Res. Counc. Rep. Memo. Techn. Rep. 2891, London 1955.
[12] Osipov S.K.: Computational and experimental study of variants of the LP flow parts in order to increase their throughput. PhD thesis, National Research University Moscow Energy Institute, Moscow 2019.
[13] Baljé O.: Turbomachines – A Guide to Design, Selection and Theory. Wiley & Sons, New York 1981.
[14] Craig H.R.M., Cox H.J.A.: Performance estimation of axial flow turbines. P.I. Mech. Eng. 185(1970), 1, 407–424.
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[17] Scoretz M., Williams R.: Industrial Steam Turbine Value Packages. GE Energy, Atlanta 2008.
[18] Minchener A.: Developments in China’s coal-fired power sector. IEA Clean Coal Centre., London 2010,
[19] Rusanov A., Rusanov R., Lampart P.: Designing and updating the flow part of axial and radial-axial turbines through mathematical modelling. Open Eng. 5(2015), 399–410.
[20] Yershov S., Rusanov A., Gardzilewicz A., Lampart P.: Calculations of 3D viscous compressible turbomachinery flows. In: Proc. 2nd Symp. on Comp. Technologies for Fluid/Thermal/Chemical Systems with Industrial Applications. ASME PVP Division Conf., 1–5 August 1999, Boston, PVP, 397.2(1999), 143–154.
[21] Godunov S.K., Zabrodin A.V., Ivanov M.Ya. et al.: Numerical Solution of Multidimensional Problems of Gas Dynamics. Nauka, Moskow 1976 (in Russian).
[22] Rusanov A.V., Lampart P., Pashchenko N.V., Rusanov R.A.: Modelling 3D steam turbine flow using thermodynamic properties of steam IAPWS-95. Pol. Marit. Res. 23(2016), 1(89), 61–67.
[23] Lampart P., Rusanov A., Yershov S., Marcinkowski S., Gardzilewicz A.: Validation of 3D RANS Solver with a state equation of thermally perfect and calorically imperfect gas on a multi-stage low-pressure steam turbine flow. J. Fluid. Eng. – T ASME 127(2005), 83–93.
[24] Lampart P., Yershov S., Rusanov A., Szymaniak M.: Tip leakage/main flow interaction in multi-stage HP turbines with short-height blading. In: Proc. ASME Turbo Expo 2004 5 B, 1359–1367.
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Authors and Affiliations

Andrii Rusanov
1
Roman Rusanov
1

  1. The A. N. Pidgorny Institute of Mechanical Engineering Problems NAS of Ukraine, Dm. Pozharsky 2/10, 61046 Kharkiv, Ukraine
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Abstract

Accurate definition of boundary conditions is of crucial importance for room acoustic predictions because the wall impedance phase angle can affect the sound field in rooms and acoustic parameters applied to assess a room reverberation. In this paper, the issue was investigated theoretically using the convolution integral and a modal representation of the room impulse response for complex-valued boundary conditions. Theoretical considerations have been accompanied with numerical simulations carried out for a rectangular room. The case of zero phase angle, which is often assumed in room acoustic simulations, was taken as a reference, and differences in the sound pressure level and decay times were determined in relation to this case. Calculation results have shown that a slight deviation of the phase angle with respect to the phase equal to zero can cause a perceptual difference in the sound pressure level. This effect was found to be due to a change in modal frequencies as a result of an increase or decrease in the phase angle. Simulations have demonstrated that surface distributions of decay times are highly irregular, while a much greater range of the early decay time compared to the reverberation time range indicates that a decay curve is nonlinear. It was also found that a difference between the decay times predicted for the complex impedance and real impedance is especially clearly audible for the largest impedance phase angles because it corresponds approximately to 4 just noticeable differences for the reverberation metrics.
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Authors and Affiliations

Mirosław Meissner
1
Tomasz G. Zieliński
1

  1. Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
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Abstract

In situ time series measurements of ocean ambient noise, have been made in deep waters of the Arabian Sea, using an autonomous passive acoustic monitoring system deployed as part of the Ocean Moored buoy network in the Northern Indian Ocean (OMNI) buoy mooring operated by the National Institute of Ocean Technology (NIOT), in Chennai during November 2018 to November 2019. The analysis of ambient noise records during the spring (April–June) showed the presence of dolphin whistles but contaminated by unwanted impulsive shackle noise. The frequency contours of the dolphin whistles occur in narrow band in the range 4–16 kHz. However, the unwanted impulsive shackle noise occurs in broad band with the noise level higher by ∼20 dB over the dolphin signals, and it reduces the quality of dolphin whistles. A wavelet based threshold denoising technique followed by a subtraction method is implemented. Reduction of unwanted shackle noise is effectively done and different dolphin whistle types are identified. This wavelet denoising approach is demonstrated for extraction of dolphin whistles in the presence of challenging impulsive shackle noise. Furthermore, this study should be useful for identifying other cetacean species when the signal of interest is interrupted by unwanted mechanical noise.
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Authors and Affiliations

Madan M. Mahanty
1
Sanjana M. Cheenankandy
1
Ganesan Latha
1
Govindan Raguraman
1
Ramasamy Venkatesan
1

  1. National Institute of Ocean Technology, Ministry of Earth Sciences, Chennai, India
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Abstract

This study used experimental measurements and the finite-element method (FEM) simulations to investigate transient underwater radiated noise induced by the impulse excitation of water surrounding a watertight steel-structured circular cylindrical shell submerged in the 176 × 8 × 4 m towing tank. The excitation was caused by dropping an iron block onto a structural bracket in the shell to generate structural vibration. The experimental results were found to be consistent with the FEM results, with the difference between the experimental and simulated sound pressure levels being less than 3 dB. Moreover, it was determined that the structural vibration also generated airborne noise in the cylindrical shell, but this contributed much less than the impulse excitation to the induction of underwater radiated noise. Finally, analysis of the sound field of the underwater noise radiation showed that it was influenced by the wall thickness of the watertight steel cylindrical shell and that of the reinforced bracket seat structure. In particular, the structural reinforcement position proved to be the diffusion breakpoint of the underwater sound radiation. This demonstrates that compared with the studied structure, a thicker and more complex reinforced structure will transmit less or incomplete sound radiation into water.
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Authors and Affiliations

Chen-I Wu
1
Gee-Pinn Too
1
Bo-Hsien Wu
1

  1. Department of Systems and Naval Mechatronic Engineering, National Cheng Kung University, Tainan, Taiwan
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Abstract

In recent years, with the rapid development of digital components, digital electronic computers, especially microprocessors, digital controllers have replaced analog controllers on many occasions. The application of digital controller makes the performance analysis of impulsive system more and more important. This paper considers global exponential stability (GES) of impulsive delayed nonlinear hybrid differential systems (IDNHDS).Through the application of the Lyapunov method and the Razumikhin technique, a series of uncomplicated and useful guiding principles have been obtained. The results of a numerical simulation are presented to demonstrate that the method is correct and effective.

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Authors and Affiliations

Qianqian Jia
Chaoying Xia
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Abstract

This article is a presentation of the analysis of new class of logarithmic analog-to-digital converter (LADC) with accumulation of charge and impulse feedback. Development of mathematical models of errors, quantitative assessment of these errors taking into account modern components and assessing the accuracy of logarithmic analog-to-digital converter (LADC) with accumulation of charge and impulse feedback were presented. (Logarithmic ADC with accumulation of charge and impulse feedback – analysis and modeling).
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Bibliography

[1] S. Purighalla, B. Maundy, “84-dB Range Logarithmic Digital-to-Analog Converter in CMOS 0.18-μm Technology,” IEEE Transactions on Circuits and Systems II: Express Briefs, 58 (2011), no.5, pp. 279-283
[2] J. Lee, J. Kang, S. Park, J. Seo, J. Anders, J. Guilherme, M. P. Flynn, “A 2.5 mW 80 dB DR 36 dB SNDR 22 MS/s Logarithmic Pipeline ADC,” IEEE Journal Of Solid-State Circuits, 44 (2009), no.10, pp. 2755-2765
[3] B. Maundy, D. Westwick, S. Gift, “On a class of pseudo-logarithmic amplifiers suitable for use with digitally switched resistors,” Int. J. of Circuit Theory and Applications, vol. 36 (2008), no.1, pp. 81–108
[4] B. Maundy, D. Westwick, S. Gift, (2007) “A useful pseudo-logarithmic circuit,” Microelectronics International, Vol. 24 Iss: 2, pp.35 - 45
[5] M. Alirieza, L. Jing and J. Dileepan, “Digital Pixel Sensor Array with Logarithmic Delta-Sigma Architecture,” Sensors, 13(8), pp. 10765-10782, August 2013
[6] J. Guilherme, J. Vital, Jose Franca, “A True Logarithmic Analog-to-Digital Pipeline Convener with 1.5bitistage and Digital Correction,” Proc. IEEE International Conference on Electronics Circuits and Systems, pp. 393-396, Malta 2001
[7] G. Bucci, M. Faccio, C. Landi, “The performance test of a piece-linear A/D converter,” IEEE Instrumentation and Measurement Technology Conference, St. Paul USA May 1998, pp.1223.1228
[8] J. Guilherme, J. Vital, J. Franca, “A CMOS Logarithmic Pipeline A/D Converter with a Dynamic Range of 80 dB,” IEEE Electronics, Circuits and Systems, 2002. 9th International Conference on, (2002), no.3/02, pp. 193-196
[9] J. Sit and R. Sarpeshkar, “A Micropower Logarithmic A/D With Offset and Temperature Compensation,” IEEE J. Solid-State Circuits, 39 (2004), nr. 2, pp. 308-319
[10] J. Mahattanakul, “Logarithmic data converter suitable for hearing aid applications,” Electronic Letters, 41 (2005), no.7, pp. 31-32
[11] S. Sirimasakul, A. Thanachayanont, W. Jeamsaksiri, “Low-Power Current-Mode Logarithmic Pipeline Analog-to-Digital Converter for ISFET based pH Sensor,” IEEE ISCIT, 2009, no.6/09, pp. 1340-1343
[12] M. Santosa, N. Hortaa, J. Guilherme, “A survey on nonlinear analog-to-digital converters,” Integration, the VLSI Journal, Volume 47, Issue 1, pp. 12–22, January 2014
[13] Z.R. Mychuda, “Logarithmic Analog-To-Digital Converters – ADC of the Future,” Prostir, Lviv, Ukraine 2002, pp. 242
[14] A. Szcześniak, Z Myczuda, “A method of charge accumulation in the logarithmic analog-to-digital converter with a successive approximation,” Electrical Review, 86 (2010), no.10, pp. 336-340
[15] A. Szcześniak, U. Antoniw, Ł. Myczuda, Z. Myczuda, „Logarytmiczne przetworniki analogowo-cyfrowe z nagromadzeniem ładunku i impulsowym sprzężeniem zwrotnym,” Electrical Review, R. 89 no. 8/2013, pp. 277 – 281
[16] A. Szcześniak, Z. Myczuda, „Analiza prądów upływu logarytmicznego przetwornika analogowo-cyfrowego z sukcesywną aproksymacją,” Electrical Review, 88 (2012), no. 5а, pp. 247-250
[17] J.H. Moon, D. Y. Kim, M. K. Song, Patent No. KR20110064514A, “Logarithmic Single-Slope Analog Digital Convertor, Image Sensor Device And Thermometer Using The Same, And Method For Logarithmic Single-Slope Analog Digital Converting,”
[18] J. Gorisse, F. A. Cathelin, A. Kaiser, E. Kerherve Patent No. EP2360838A1, “Method for logarithmic analog-to-digital conversion of an analog input signal and corresponding apparatus,”
[19] R. Offen Patent No. DE102008007207A1 “Logarithmierender Analog-Digital Wandler,”
[20] H. Suzunaga Patent No. US20080054163A1, “Logarithmic-compression analog-digital conversion circuit and semiconductor photosensor device,”
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Authors and Affiliations

Zynoviy Mychuda
1
Lesya Mychuda
1
Uliana Antoniv
1
Adam Szcześniak
2

  1. Lviv Polytechnic National University, Department of the Computer-Assisted Systems of Automation, Ukraine
  2. University of Technology in Kielce, Department of Mechatronics and Machine Building, Poland
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Abstract

This article is a presentation of the analysis of new class of logarithmic analog-to-digital converter (LADC) with accumulation of charge and impulse feedback. LADC construction, principle of operation and dynamic properties were presented. They can also be part of more complex converters and systems based on LADC. LADC of this class is perspective for implementation in the form of integrated circuit, as the number of switched capacitors needed to conversion is minimized to one capacitor. (Logarithmic ADC with accumulation of charge and impulse feedback – construction, principle of operation and dynamic properties)
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Bibliography

[1] S. Purighalla, B. Maundy, “84-dB Range Logarithmic Digital-to-Analog Converter in CMOS 0.18-μm Technology”, IEEE Transactions on Circuits and Systems II: Express Briefs, 58 (2011), no.5, pp. 279-283
[2] J. Lee, J. Kang, S. Park, J. Seo, J. Anders, J. Guilherme, M. P. Flynn, “A 2.5 mW 80 dB DR 36 dB SNDR 22 MS/s Logarithmic Pipeline ADC,” IEEE Journal Of Solid-State Circuits, 44 (2009), no.10, pp. 2755-2765
[3] B. Maundy, D. Westwick, S. Gift, “On a class of pseudo-logarithmic amplifiers suitable for use with digitally switched resistors,” Int. J. of Circuit Theory and Applications, vol. 36 (2008), no.1, pp. 81–108
[4] B. Maundy, D. Westwick, S. Gift, (2007) “A useful pseudo-logarithmic circuit,” Microelectronics International, Vol. 24 Iss: 2, pp.35 - 45
[5] M. Alirieza, L. Jing and J. Dileepan, “Digital Pixel Sensor Array with Logarithmic Delta-Sigma Architecture,” Sensors, 13(8), pp. 10765- 10782, August 2013
[6] J. Guilherme, J. Vital, Jose Franca, “A True Logarithmic Analog-to- Digital Pipeline Convener with 1.5bitistage and Digital Correction,” Proc. IEEE International Conference on Electronics Circuits and Systems, pp. 393-396, Malta 2001
[7] G. Bucci, M. Faccio, C. Landi, “The performance test of a piece-linear A/D converter,” IEEE Instrumentation and Measurement Technology Conference, St. Paul USA May 1998, pp.1223.1228
[8] J. Guilherme, J. Vital, J. Franca, “A CMOS Logarithmic Pipeline A/D Converter with a Dynamic Range of 80 dB,” IEEE Electronics, Circuits and Systems, 2002. 9th International Conference on, (2002), no.3/02, pp. 193-196
[9] J. Sit and R. Sarpeshkar, “A Micropower Logarithmic A/D With Offset and Temperature Compensation,” IEEE J. Solid-State Circuits, 39 (2004), nr. 2, pp. 308-319
[10] J. Mahattanakul, “Logarithmic data converter suitable for hearing aid applications,” Electronic Letters, 41 (2005), no.7, pp. 31-32
[11] S. Sirimasakul, A. Thanachayanont, W. Jeamsaksiri, “Low-Power Current-Mode Logarithmic Pipeline Analog-to-Digital Converter for ISFET based pH Sensor,” IEEE ISCIT, 2009, no.6/09, pp. 1340-1343
[12] M. Santosa, N. Hortaa, J. Guilherme, “A survey on nonlinear analog-todigital converters,” Integration, the VLSI Journal, Volume 47, Issue 1, pp. 12–22, January 2014
[13] Z.R. Mychuda, “Logarithmic Analog-To-Digital Converters – ADC of the Future,” Prostir, Lviv, Ukraine 2002, pp. 242
[14] A. Szcześniak, Z Myczuda, “A method of charge accumulation in the logarithmic analog-to-digital converter with a successive approximation,” Electrical Review, 86 (2010), no.10, pp. 336-340
[15] A. Szcześniak, U. Antoniw, Ł. Myczuda, Z. Myczuda, „Logarytmiczne przetworniki analogowo-cyfrowe z nagromadzeniem ładunku i impulsowym sprzężeniem zwrotnym,” Electrical Review, R. 89 no. 8/2013, pp. 277 – 281
[16] A. Szcześniak, Z. Myczuda, „Analiza prądów upływu logarytmicznego przetwornika analogowo-cyfrowego z sukcesywną aproksymacją,” Electrical Review, 88 (2012), no. 5а, pp. 247-250
[17] J.H. Moon, D. Y. Kim, M. K. Song, Patent No. KR20110064514A, “Logarithmic Single-Slope Analog Digital Convertor, Image Sensor Device And Thermometer Using The Same, And Method For Logarithmic Single-Slope Analog Digital Converting,”
[18] J. Gorisse, F. A. Cathelin, A. Kaiser, E. Kerherve Patent No. EP2360838A1, “Method for logarithmic analog-to-digital conversion of an analog input signal and corresponding apparatus,”
[19] R. Offen Patent No. DE102008007207A1 “Logarithmierender Analog- Digital Wandler,”
[20] H. Suzunaga Patent No. US20080054163A1, “Logarithmic-compression analog-digital conversion circuit and semiconductor photosensor device,”
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Authors and Affiliations

Zynoviy Mychuda
1
Lesya Mychuda
1
Uliana Antoniv
1
Adam Szcześniak
2

  1. Lviv Polytechnic National University, Department of the Computer-Assisted Systems of Automation, Ukraine
  2. University of Technology in Kielce, Department of Mechatronics and Machine Building, Poland
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Abstract

The aim of this paper is to compare three different methods of analysis of results of lightning impulse breakdown voltage measurements of solid materials such as insulating pressboard. These three methods are the series method, the step method and the up-and-down method which are applied to withstand voltage estimation commonly in high voltage engineering. To obtain the data needed for the analysis a series of experimental studies was carried out. It included studies of mineral oil and natural ester impregnating 1 mm of thick cellulose-based pressboard. In order to show the distribution of breakdown voltage the Weibull distribution was additionally applied in data analysis. The results were also assessed from the viewpoint of dielectric liquid used for impregnation. The studies carried out showed that series and step methods give comparable results opposite to the up-and-down method. The latest overstates the results for mineral oil impregnated pressboard and understates for natural ester impregnated pressboard when juxtaposing them with the rest of the methods applied. In addition, there is lack of possibility to assess the withstand voltage for the up-and-down method directly from the vector of random variable. It is possible only as a result of a specially developed equation which always arouses doubt. From the methods applied it seems that the step method can be a great substitution for the series method as intuitive, fast in application and limiting the number of samples in solid insulation material testing.
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Bibliography

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[2] Rozga, P. (2016). Streamer propagation in a non-uniform electric field under lightning impulse in short gaps insulated with natural ester and mineral oil. Bulletin of the Polish Academy of Sciences: Technical Science, 64(1), 171–179. https://doi.org/10.1515/bpasts-2016-0019
[3] Rozga, P. (2016). Using the three-parameter Weibull distribution in assessment of threshold strength of pressboard impregnated by different liquid dielectrics. IET Science, Measurement & Technology, 10(6), 665–670. https://doi.org/10.1049/iet-smt.2016.0061
[4] Aniserowicz, K. (2019). Analytical calculations of surges caused by direct lightning strike to underground intrusion detection system. Bulletin of the Polish Academy of Sciences: Technical Science, 67(2), 263–269. https://doi.org/10.24425/bpas.2019.128118
[5] Mosinski, F. (1995). Metody statystyczne w technice wysokich napięć. Wydawnictwo Politechniki Łódzkiej. (in Polish)
[6] Vibholm, S., & Thyregod, P. (1988). A study of the up-and-down method for non-normal distribution functions. IEEE Transactions on Electrical Insulation, 23(3), 357–364. https://doi.org/10.1109/14.2375
[7] Rozga, P. (2019). Lightning strength of gas, liquid and solid insulation – experience formthe laboratory tests. The International Conference on Power Transformers “Transformer’19”, 199–212.
[8] Khaled, U., & Beroual, A. (2020). Lightning impulse breakdown voltage of synthetic and natural ester liquids-based Fe3O4, Al2O3 and SiO2 nanofluids. Alexandria Engineering Journal, 59(5), 3709–3713. https://doi.org/10.1016/j.aej.2020.06.025
[9] Zhang, Q., You, H., Guo, C., Qin, Y., Ma, J., &Wen, T. (2016) Experimental research of dispersion of SF6 discharge breakdown voltage under lighting impulse. High Voltage Engineering, 42(11), 3415– 3420.
[10] Zhang, Y., Xie, S., Jiang, X., Ye, L., Zhang, Ch., Sun, P., Mu, Z., & Sima, W. (2019). Study on consistency of failure probability characteristics of oil-paper insulation under different impulse voltages. Proceedings of the 21st International Symposium on High Voltage Engineering, 1192–1206. https://doi.org/10.1007/978-3-030-31676-1_111
[11] Cousineau, D. (2009). Fitting the three-parameter Weibull distribution: review and evaluation of existing and new methods. IEEE Transactions on Dielectrics and Electrical Insulation, 16(1), 281– 288. https://doi.org/10.1109/TDEI.2009.4784578
[12] European Standards. (2014). Electric strength of insulating materials – Test methods – Part 3: Additional requirements for 1,2/50 μs impulse tests (IEC 60243-3: 2014).
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[14] Shen, Z., Wang, F., Wang, Z., Li, J. (2021). A critical review of plant-based insulating fluids for transformer: 30 years of development. Renewable and Sustainable Energy Reviews, 41, 110783. https://doi.org/10.1016/j.rser.2021.110783
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[25] European Standards. (2011). Power transformers – Part 1: General (IEC 60076-1:2011)
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Authors and Affiliations

Artur Klarecki
1 2
Paweł Rózga
1
Filip Stuchała
1

  1. Lodz University of Technology, Institute of Electrical Power Engineering, Stefanowskiego 18/22, 90-924 Lodz, Poland
  2. Lodz University of Technology, Interdisciplinary Doctoral School, Zeromskiego 116, 90-924 Lodz, Poland
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Abstract

The article describes and compares two OFDM based communications schemes for reducing the effects of the combination of Narrowband Interference (NBI) and Impulsive Noise (IN), which are noise types typical in Power Line Communication (PLC). The two schemes are Modified BPSK-OFDM (called MBPSK, for brevity) and QFSK-OFDM (called QFSK, for brevity), which are non-conventional OFDM schemes. We give a description of the two schemes, showing how they are derived and also show their similarities and eventually compare their performances. Performance simulation results, in terms of bit error rate, are given to compare the systems under the effect of IN and NBI. The popular Middleton Class A model is used for modelling IN. The results show that MBPSK scheme outperforms the QFSK scheme in terms of minimum distance, and hence in terms of bit error probability when no preprocessing is performed. However, under clipping/nulling, both schemes eventually reach the bit error rate floor.

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Authors and Affiliations

Abiola G. Bolaji
Thokozani Shongwe
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Abstract

In the paper, maximal values xe(τ) of the solutions x(t) of the linear differential equations excited by the Dirac delta function are determined. The analytical solutions of the equations and also the maximal positive values of these solutions are obtained. The analytical formulae enable the design of the system with prescribed properties. The complementary case to the earlier paper is presented. In an earlier paper it was assumed that the roots si are different, and now we consider the case when s1 = s2  = … = sn.

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Authors and Affiliations

Henryk Górecki
1
Mieczysław Zaczyk
1

  1. AGH University of Science and Technology, Department of Automatics and Robotics, Al. Mickiewicza 30, 30-059 Kraków, Poland
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Abstract

The present paper describes an experimental methodology of identification of dynamic characteristics of a track structure, consisting in determination of a track decay rate (TDR) in the field tests that were conducted by the authors on the railway line section inWarsaw. The proposed methodology of measurements, parameters determination and presentation of the results is based on the measurement methods described in EN 15461 [1], which are aimed at determination of TDR. The values of TDR determined in the impulse tests in one-third octave bands are compared with the limiting values specified in EN ISO 3095 [2] and Technical Specifications for Interoperability (TSI) [3]. Based on the obtained experimental data, the analysed railway line is classified as a structure that does not generate excessive level of rolling noise from the vibrations induced by the moving rolling stock on structural elements of the track – particularly on rails. The results obtained in this study are promising from the point of view of future development of effective solutions used for protection of people and environment against noise generated by the railway traffic.
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Authors and Affiliations

Cezary Kraśkiewicz
1
ORCID: ORCID
Przemysław Mossakowski
1
ORCID: ORCID
Artur Zbiciak
1
ORCID: ORCID
Anna Al Sabouni-Zawadzka
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
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Abstract

To overcome the detrimental influence of α impulse noise in power line communication and the trap of scarce prior information in traditional noise suppression schemes , a power iteration based fast independent component analysis (PowerICA) based noise suppression scheme is designed in this paper. Firstly, the pseudo-observation signal is constructed by weighted processing so that single-channel blind separation model is transformed into the multi-channel observed model. Then the proposed blind separation algorithm is used to separate noise and source signals. Finally, the effectiveness of the proposed algorithm is verified by experiment simulation. Experiment results show that the proposed algorithm has better separation effect, more stable separation and less implementation time than that of FastICA algorithm, which also improves the real-time performance of communication signal processing.

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Authors and Affiliations

Wei Zhang
ORCID: ORCID
Zhongqiang Luo
Xingzhong Xiong
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Abstract

In this paper we prove the exact controllability of a time varying semilinear system considering non-instantaneous impulses, delay, and nonlocal conditions occurring simultaneously. It is done by using the Rothe’s fixed point theorem together with some sub-linear conditions on the nonlinear term, the impulsive functions, and the function describing the nonlocal conditions. Furthermore, a control steering the semilinear system from an initial state to a final state is exhibited.
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Authors and Affiliations

Dalia Cabada
1
Katherine Garcia
2
Cristi Guevara
3
Hugo Leiva
2
ORCID: ORCID

  1. School of Mathematical and Statistical Sciences, Arizona State University, United States of America
  2. School of Mathematical Sciences and Information Technology, Yachay Tech University, Ecuador
  3. Arizona Department of Education, United States of America

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