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1

Memory dependent triple-phase-lag thermo-elasticity in thermo-diffusive medium

Yadav Anand Kumar, Singh Aarti, Jurczak Paweł

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 4

137--162

EN

The objective of the paper is to look at the propagation and reflection of plane waves in a thermo-diffusion isotropic medium. The reflection of plane waves in a thermo-diffusion medium was investigated in this study with reference to triple phase lag thermo-elasticity. The memory dependent derivative (MDD) is applied for this investigation. The fundamental equations are framed and solved for a particular plane. The four plane waves that are propagating across the medium are, shown namely: longitudinal displacement, P-wave, thermal diffusion T-wave, mass diffusion MD-wave and shear vertical SV-wave. These four plane wave velocities are listed for a specific medium, illustrating the impact of the diffusion coefficient and are graphically represented. Expressions for the reflection coefficient for the incidence plane wave are produced from research on the reflection of plane waves from the stress-free surface. It should be noted that these ratios are graphically represented and shown when diffusion and memory dependent derivative (MDD) factors are in play. The new model is relevant to many different fields, including semiconductors, earth- engineering, and electronics, among others, where thermo-diffusion elasticity is significant. Diffusion is a technique that can be applied to the production of integrated circuits, MOS transistors, doped polysilicon gates for the base and emitter in transistors, as well as for efficient oil extraction from oil reserves. Wave propagation in a thermos-diffusion elastic media provides crucial information about the presence of fresh and enhanced waves in a variety of technical and geophysical contexts. For experimental seismologists, developers of new materials, and researchers, this model might be useful in revising earthquake estimates.

2

The River System Pollutant Migration in the Context of the Sudden One-Time Discharge with Consideration of the Bottom Sediments Influence (Case of Benzene Migration in the Stryi River, Ukraine)

Kuzyk Andriy, Karabyn Vasyl, Shuryhin Vladyslav, Sushko Yulia, Stepova Kateryna, Karabyn Oksana

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 1

46--54

EN

Basing on the mathematical model developed with the account of influence of bottom sediments, the parameters of benzene migration in the river caused by one-time discharge into the Stryi River were investigated. The mathematical model of migration consists of two equations that describe the movement of pollutants in the river system, taking into account the flow rate, diffusion, sorption and desorption of the pollutant by the bottom sediments of the river. The parameters of benzene distribution in the "water-bottom sediments" system were experimentally determined under laboratory conditions. With the help of computer modeling, the temporal and spatial distributions of benzene in water and bottom sediments were obtained. The regularities of benzene concentration change depending on the composition of the bottom sediments of the river have been established. The dependencies can be extrapolated to other river systems and pollutants.

3

Prediction of Benzene Migration Parameters Resulting from Continuous Flow in a Mountain River

Shuryhin Vladyslav, Karabyn Vasyl, Kuzyk Andriy

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 8

73--81

EN

Using a mathematical model that includes the influence of bottom sediments, a comprehensive study of the migration of benzene (C6H6) as a result of its continuous release into a mountain river was conducted. The adopted migration model consists of two equations that accurately describe the movement of pollutants within the river system, considering crucial factors such as flow velocity, diffusion, sorption, and desorption by river sediments. Through meticulous laboratory experiments, the distribution parameters that govern the behavior of benzene (C6H6) within the water-sediment system were successfulully determined. Leveraging advanced computer modeling techniques, intricate spatiotemporal profiles illustrating benzene (C6H6) concentrations in both water and sediments were generated. Furthermore, consistent patterns in the fluctuations of benzene (C6H6) concentrations that exhibit strong correlation with the specific composition of river sediments were identified. Importantly, these foundational relationships can be extrapolated to diverse river systems and various categories of pollutants.

4

Interface Diffusion Behavior of Co40Al-X (X = Ni, Cr, Ti) System by Diffusion Multiple

Shang Hang, Gao Qiuzhi, Jiang Yujiao, Ma Qingshuang, Li Huijun, Zhang Hailian

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

275--286

EN

Diffusion multiple method was applied to investigate the alloying elements distribution and interface diffusion reactions in Co-Al-X system, in order to accelerate the alloy development. The diffusion regions of Co-Al-X system at 1173 K were investigated by scanning electron microscope (SEM) and nanoindentation. SEM images show that phases of Co-Al-Ni diffusion interface consisted of β-CoAl + γ Co, γ Co, γ + γ'-(Co, Ni)3Al and γ Ni, while Co-Al-Cr diffusion interface is shaped with δ + γ + β, γ and σ region. TiNiX diffusion layer with high Ni-content was formed in Co-Al-Ti diffusion interface. The diffusion layers during diffusion multiple play an important role in mechanical properties in these alloying systems. The γ + γ' diffusion layer in Co-Al-Ni diffusion interface presented the best comprehensive performance, while the highest hardness (17.48 GPa) was confirmed in Co-Al-Cr diffusion interface due to a large number of brittle phases. Darken method was applied to determine the interdiffusion coefficients of alloying elements in pseudo-binary phase, accordingly the diffusion capacities of alloying elements can be ordered as Al > Ni > Cr in Co-based alloys.

5

Gas Nitriding of the Near-Beta-Titanium Alloy

Luk’yanenko Alexander G., Pohrelyuk Iryna M., Fedirko Viktor M., Molyar A. G., Trush Vasyl, Kravchyshyn T. M.

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 2

431--438

EN

The present research investigates the nitriding kinetics of the near-beta-titanium alloy of Ti-Al-Nb-Fe-Zr-Mo-V system at 750, 800, and 850°C in gaseous nitrogen at 105 Pa for 2, 4, and 8 h. The parabolic coefficient kp of the layer’s growth rate and the nitriding activation energy E are set as the kinetic parameters of the nitrided layer’s growth. The activation energy for the formation of a nitride layer is ~108 kJ/mol. The authors discuss the morphology of the nitride layers as well as their roughness and surface hardness. The study determines the effective diffusion coefficient for the growth of diffusion layers in the temperature range of 750...850°C: Def = D0 × exp (-E/RT), where D0 = 0.0177 m2/s; E = 215.7 kJ/mol. The friction coefficient of the disk from nearbeta-titanium alloy with a bronze block is lowered by significantly more than 10 times after gas nitriding, and the temperature in the friction zone is reduced by 2.5 times.

6

Dynamical properties of a modified chaotic Colpitts oscillator with triangular wave non-linearity

Suresh Rasappan, Sathish Kumar Kumaravel, Regan Murugesan, Niranjan Kumar K. A., Narmada Devi R., Obaid Ahmed J.

Archives of Control Sciences

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2023

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Vol. 33, No. 1

25--53

EN

The purpose of this paper is to introduce a new chaotic oscillator. Although different chaotic systems have been formulated by earlier researchers, only a few chaotic systems exhibit chaotic behaviour. In this work, a new chaotic system with chaotic attractor is introduced for triangular wave non-linearity. It is worth noting that this striking phenomenon rarely occurs in respect of chaotic systems. The system proposed in this paper has been realized with numerical simulation. The results emanating from the numerical simulation indicate the feasibility of the proposed chaotic system. More over, chaos control, stability, diffusion and synchronization of such a system have been dealt with.

7

Use of solar energy in the technology of fruit drying

Korobka Serhiy, Boyarchuk Vitaliy, Syrotiuk Valerii, Syrotyuk Serhiy, Stukalets Igor, Golovko Volodymyr, Syrotyuk Hanna, Jakubowski Tomasz, Giełżecki Jan

Przegląd Elektrotechniczny

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2022

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R. 98, nr 6

37--44

EN

Companies in the agri-food industry of Ukraine are trying to rationally manage all forms of energy (including solar energy) needed to implement the production process. The study investigated the process of drying plant material (fruit) based on the use of solar energy (and the intensification of this process). The present process uses a combination of an air collector and a drying chamber. The measurable effect of the performed tests is the development of diagnostic techniques for heat transfer with alternative diffusion and moisture transfer potentials (the experiment was performed at the temperature of 25-60⁰C, drying time was 50-74 hours). The method is offered to calculate the diffusion and moisture transfer when drying the fruit in a solar dryer. The method enables the diagnosis of heat exchange processes and the analysis of the mathematical model of heat exchange processes [1]. The results of the research (analytical and experimental) indicate the possibility of intensifying the fruit drying process based on the solar dryer. The unit energy consumption during fruit drying in a solar dryer is reduced by 3-3.7 MJ/kg in relation to the currently used convection drying devices.

PL

Firmy z branży rolno-spożywczej Ukrainy starają się racjonalnie gospodarować wszystkimi formami energii (w tym energią słoneczną) potrzebną do realizacji procesu produkcyjnego. W pracy zbadano proces suszenia materiału roślinnego (owoców) w oparciu o wykorzystanie energii słonecznej (i intensyfikację tego procesu). Niniejszy proces wykorzystuje połączenie kolektora powietrznego i komory suszącej. Wymiernym efektem przeprowadzonych badań jest opracowanie technik diagnostycznych wymiany ciepła o alternatywnych potencjałach dyfuzji oraz przenoszenia wilgoci (doświadczenie przeprowadzono w temperaturze 25 ⁰C – 60 ⁰C, czas suszenia 50-74 godz.). Metoda oblicza dyfuzję i transfer wilgoci podczas suszenia owoców w suszarce słonecznej. Metoda umożliwia analizę procesów wymiany ciepła oraz modelu matematycznego procesów wymiany ciepła [1]. Wyniki badań (analitycznych i eksperymentalnych) wskazują na możliwość intensyfikacji procesu suszenia owoców w oparciu o suszarkę słoneczną. Jednostkowe zużycie energii podczas suszenia owoców w suszarni solarnej zmniejsza się o 3 MJ/kg - 3,7 MJ/kg w stosunku do obecnie stosowanych urządzeń do suszenia konwekcyjnego.

8

An improved chaotic system-based 1D logistic map applied to gray scale images encryption

Belilita Fairouz, Bekkouche Tewfik, Amardjia Nourredine

Przegląd Elektrotechniczny

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2022

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R. 98, nr 5

130--133

EN

In this paper, we propose an improved chaotic system inspired from the classical 1D Logistic map. The main idea consists in enhancing the performance of the control parameter by extending its chaotic range. The improved Logistic map (ILM) is applied to gray scale encryption images using the confusion-diffusion architecture. The input image is first chaotically scrambled before performing an element by element recursive XOR on its successive chosen blocks of ሺ8 ൈ 8ሻ or ሺ16 ൈ 16ሻ. Obtained result is reshaped to give the encrypted image. Computer simulations prove the performances of this method in terms of histogram analysis, correlation and sensitivity analysis.

PL

W tym artykule proponujemy ulepszony chaotyczny system inspirowany klasyczną mapą logistyczną 1D. Główną ideą jest zwiększenie wydajności parametru kontrolnego poprzez rozszerzenie jego chaotycznego zakresu. Ulepszona mapa logistyczna (ILM) jest stosowana do obrazów szyfrowania w skali szarości przy użyciu architektury pomyłek-rozproszenia. Obraz wejściowy jest najpierw chaotycznie zaszyfrowany przed wykonaniem element po elemencie rekurencyjnego XOR na jego kolejnych wybranych blokach (8×8) lub (16×16). Otrzymany wynik jest przekształcany w celu uzyskania zaszyfrowanego obrazu. Symulacje komputerowe potwierdzają wydajność tej metody w zakresie analizy histogramu, korelacji i analizy wrażliwości.

9

Double-image encryption scheme based on the phase-truncated multiple-parameter Fresnel transform

Zhou Ling, Zhou Hang, Ma Yan, Zhou Nan-Run

Optica Applicata

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2022

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Vol. 52, nr 2

163--177

EN

A double-image encryption algorithm is proposed with the phase-truncated multiple-parameter Fresnel transform. Firstly, the pixel positions of two plaintext images are scrambled and then the results are merged into one image with the scrambling operation. Subsequently, the resulting image is encrypted by phase truncation and phase reservation in the multiple-parameter Fresnel transform domain. The phase information is scrambled by the affine transform and then recombined with the amplitude information. The final encryption image is obtained with the pixel scrambling and diffusion methods to further enhance the security of the image encryption system, where the scrambling and diffusion operations are based on logistic map, logistic-sine system and 2D logistic-adjusted-sine map. The image encryption scheme is robust against the common attacks due to the nonlinear properties of diffusion and phase truncation. Numerical simulation results verify the performance and the security of the proposed double-image algorithm based on the phase-truncated multiple-parameter Fresnel transform.

10

Mathematical modelling by convection-diffusion with reaction of organic pollution in the wadi Mouillah stream, north-western Algeria

Benadda Lotfi, Djelita Belkheir, Chiboub-Fellah Abdelghani

Journal of Water and Land Development

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2022

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no. 54

26--37

EN

This work describes the behaviour of organic pollutants along the wadi Mouillah watercourse and its main tributaries and their impacts on the Hammam Boughrara dam, located in the NW of Algeria, in the Wilaya of Tlemcen. The use of a database relating to physico-chemical, biotic and hydrological variables, covering the period from January 2006 to December 2009, contributed to the understanding of the spatiotemporal evolution of each variable. The application of a mathematical model of the diffusion by convection-dispersion with a reaction on two characteristic parameters of organic pollution, the biochemical oxygen demand (BOD5) which records values above the norm, with peaks that can reach 614%, and total phosphorus (Ptot), which the concentration is always higher with maxima reaching 53 mg∙dm-3 favouring eutrophication; this made it possible with precision to synthesise the propagation of pollutants in the liquid mass. The results obtained on the waters of Wadi Mouillah are therefore of poor quality; there is a need to set up a rigorous water quality monitoring system, with water treatment and decontamination devices to preserve the water resources. This will allow to contribute to better management of water quality in terms of combating the spread of pollution. Therefore, they can be used to support decisions in the context of sustainable development.

11

A Diffusion Model of Binary Systems Controlled by Chemical Potential Gradient

Wróbel Marek, Burbelko Andriy

Journal of Casting & Materials Engineering

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2022

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Vol. 6, no. 2

39--44

EN

The paper presents a model of diffusion in a single phase with chemical potential gradient as the driving force of the process. Fick’s laws are strictly empirical and the assumption that the concentration gradients are the driving forces of diffusion is far from precise. Instead, the gradient of chemical potential μi of component i is the real driving force. The matter of governing equations of models that incorporate this approach will be raised and discussed in this article. One of more important features is the ability to acquire results where diffusion against the concentration gradient may occur. The presented model uses the Finite Difference Method (FDM) and employs the CALPHAD method to obtain chemical potentials. The calculations of chemical potential are carried out for instant conditions – temperature and composition – in the entire task domain by Thermo-Calc via a TQ-Interface. Then the heterogeneity of chemical potentials is translated into mass transfer for each individual element. Calculations of two modelling tasks for one-dimension diffusion field were carried out. First: isothermal conditions with linear initial composition distribution and second: constant temperature gradient with uniform chemical composition in the specimen. Results for two binary solid solutions: Fe-C and Fe-Si, in the FCC phase for the given tasks will be presented. Modelling allows us to estimate the time needed to reach a desired state in a particular equilibrium or quasi-equilibrium state. It also shows the path of the composition change during the process. This can be used to determine whether the system at some point is getting close to the formation of another phase due to significant deviation from its initial conditions.

12

Strouhal number effects on dynamic boundary layer evolution over a wedge surface from initial flow to steady flow: analytical approach

Bachiri Mohamed, Bouabdallah Ahcen

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 4

26--39

EN

The present work studies the effects of the physical parameter characterizing the laminar flow regime, namely the Strouhal number, on the evolution of the unsteady dynamic boundary-layer developed along a wedge surface. Similarity method is used to transform unsteady momentum equation to dimensionless form. Using superposition method between diffusion and convective flows solutions, an ad hoc velocity profile formula is proposed. The obtained results confirm perfectly the numerical data given by Blasius, Falkner-Skan and Williams-Rhyne for all Strouhal numbers. A new accurate analytical function of the local skin friction is established for all time values and for different wedge surface directions. In order to give further clarification on the flows evolutions from diffusion flow to convective flow, in the whole space domain, new skin friction coefficient curves are plotted for all Strouhal numbers and for different wedge surface directions.

13

Fundamental Solutions in the Theory of Micromorphic Thermoelastic Diffusion Materials with Microtemperatures and Microconcentrations

Kansal Tarun

Computational Methods in Science and Technology

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2022

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Vol. 28, No. 1

11--25

EN

The main purpose of this paper is to construct the fundamental solutions of a system of equations of isotropic micromorphic thermoelastic diffusion materials with microtemperatures and microconcentrations in case of steady oscillations in terms of elementary functions. In a particular case, the fundamental solutions of the system of equations of equilibrium theory of isotropic micromorphic thermoelastic diffusion materials with microtemperatures and microconcentrations are also established.

14

Water absorption behavior and its effect on Charpy impact test of jute yarn reinforced polyester composites

Djeghader Djamel, Redjel Bachir

Composites Theory and Practice

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2022

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R. 22, nr 2

65--71

EN

Plates of bidirectional jute/polyester composite material were manufactured by the contact molding method. These plates were cut to form notched test pieces 80x15x4 mm and immersed in water (1, 10, 30, 90, 180 and 270 days) in order to study the impact behavior of this material. The studied composite exhibited a water saturation limit after an immersion period of approximately 30 days, with Fickian diffusion of water within the material. Williams’ method based on linear elastic fracture mechanics was used to calculate impact toughness GIC, which is due to the intrinsic characteristics of the material.

15

Gaseous Nitriding of Binary Ni-Cr Alloys - Observation and Interpretation of Microstructural Features

Kodentsov A., Cserháti C.

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

1007--1020

EN

Gaseous nitriding of binary Ni-Cr solid-solution alloys was studied at 1125ºC over the range 1 to 6000 bar of N2-pressure. At the specified temperature the nitriding response of the Ni-Cr alloys depends on the Cr-content in the initial alloy and activity (fugacity) of nitrogen at the gas/metal interface. Transition from cubic δ-CrN to hexagonal β-Cr2N precipitation occurs within the reaction zone after nitrogenization at 1125ºC under nitrogen pressure 100-6000 bar when chromium content in the initial alloy is 28 at. % or higher. It was found that a ternary phase, π (Cr12.8Ni7.2N4.0) is formed inside the Ni32Cr alloy upon cooling in nitrogen after nitriding at 1125ºC and 1 bar of N2. Experimental evidence is presented that π-phase is involved in peritectoid relations with β-Cr2N and γ-(Ni-Cr) solid solution. It was also demonstrated that nitriding behaviour of the Ni-Cr alloy can be rationalized using pertinent phase diagram information, but, in some cases, effect of mechanical stresses induced upon the internal precipitation can vitiate this prediction.

16

Effect of chemical composition of boriding agent on the optimization of surface hardness and layer thickness on AISI 8620 steel by solid and liquid boriding processes

Kul Mehmet, Yılmaz Yasin, Oskay Kürşad Oğuz, Kumruoğlu Levent Cenk

Advances in Materials Science

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2022

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Vol. 22, nr 3(73)

14--22

EN

Surfaces of cam shafts made of AISI 8620 steels were hardened by boriding processes in both solid and liquid mediums. Various chemical agents were used to achieve boride layers on the surfaces of the cam shafts in these processes. It was aimed to examine effects of the chemical agents on microhardness and thickness of the boride layers obtained. It was concluded that a bath composition of 5% B4C-90% SiC-5% KBF4 was appropriate for the hardest and thickest boride layer achieved in the solid medium, and a composition of 70% Na2B4O7-30% B4C in the liquid medium.

17

Influence of diffusion and impedence parameters on wave propagation in thermoelastic medium

Kaushal Sachin, Kumar Rajneesh, Parmar Kulwinder

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 4

99--112

EN

The aim of the present paper is to study the impact of diffusion and impedance parameters on the propagation of plane waves in a thermoelastic medium for Green and Lindsay theory (G-L) and the Coupled theory (C-T) of thermoelasticity. Results are demonstrated for impedance boundary conditions and the amplitude ratios of various reflected waves against the angle of incidence are calculated numerically. The characteristics of diffusion, relaxation time and impedence parameter on amplitude ratios have been depicted graphically. Some cases of interest are also derived from the present investigation.

18

Characteristics of the MK-40 and MA-40 Membranes for Industrial Wastewater Treatment – A Review

Gubari Mohammed Qader, Zwain Haider M., Al-Zahiwat Murtadha Mohammed, Alekseeva Nadezda Vyacheslavovna

Ecological Engineering & Environmental Technology

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2021

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Vol. 22, iss. 1

39--50

EN

Industrial application of ion exchange membranes (IEMs) for saline water desalination is widely used. In this review, two kinds of IEMs were targeted and focused on: cation-exchange membrane (MK-40) and anion-exchange membrane (MA-40). The characteristics of ion-exchange capacity, structural water content, electrical conductivity and diffusion permeability of counter ions and co-ions, as well as the properties in diffusion of alkaline media were reviewed. IEMs are anionic or cationic fixed exchange groups; the diffusion flows of the two IEMs are scarcely impacted by the kind of an ion selective membrane, as well as of the concentration dependence. The salt diffusion coefficient increases alongside the water content in the membrane, whereas the electrical conductivity increases along with the ion exchange capacity (IEC). In addition, the permeability of the charged polymer increases along with the salt concentration, while for the uncharged polymer it decreases. Thus, the methods and formulas for determining the salt diffusion coefficient and osmotic permeability were studied. Evidently, the differences in the microstructure between membranes will significantly affect the permeability of salt transport in IEMs.

19

Dynamics, control, stability, diffusion and synchronization of modified chaotic Colpitts oscillator

Rasappan Suresh, Niranjan Kumar K. A.

Archives of Control Sciences

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2021

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Vol. 31, No. 3

731--759

EN

The purpose of this paper is to introduce a new chaotic oscillator. Although different chaotic systems have been formulated by earlier researchers, only a few chaotic systems exhibit chaotic behaviour. In this work, a new chaotic system with chaotic attractor is introduced. It is worth noting that this striking phenomenon rarely occurs in respect of chaotic systems. The system proposed in this paper has been realized with numerical simulation. The results emanating from the numerical simulation indicate the feasibility of the proposed chaotic system. More over, chaos control, stability, diffusion and synchronization of such a system have been dealt with.

20

Image encryption based on permutation polynomials over finite fields

Wu Jianhua, Liu Hai, Zhu Xishun

Optica Applicata

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2020

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Vol. 50, nr 3

357--376

EN

In this paper, we propose an image encryption algorithm based on a permutation polynomial over finite fields proposed by the authors. The proposed image encryption process consists of four stages: i) a mapping from pixel gray-levels into finite field, ii) a pre-scrambling of pixels’ positions based on the parameterized permutation polynomial, iii) a symmetric matrix transform over finite fields which completes the operation of diffusion and, iv) a post-scrambling based on the permutation polynomial with different parameters. The parameters used for the polynomial parameterization and for constructing the symmetric matrix are used as cipher keys. Theoretical analysis and simulation demonstrate that the proposed image encryption scheme is feasible with a high efficiency and a strong ability of resisting various common attacks. In addition, there are not any round-off errors in computation over finite fields, thus guaranteeing a strictly lossless image encryption. Due to the intrinsic nonlinearity of permutation polynomials in finite fields, the proposed image encryption system is nonlinear and can resist known-plaintext and chosen-plaintext attacks.