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In this paper the authors studied ordered algebraic structures (semimodules) which generalize rings, fields, modules and vector spaces as known from the theory of Algebra. Additionally these structures will be ordered and will satisfy monotonicity conditions similar to the case of ordered semigroups. In this paper we discuss the following results. (1) A linearly ordered integral domain R can be embedded in a linearly ordered field. (2) Let H be an ordered semimodule over R. (a) If H is a group then x ≤ y ⇒ x □ c ≤ y □ c for all x, y ∈ R and c ∈ H, implies x □ d ≥ y □ d for d ∈ H and d ≤ e (d ∈ H). (b) If R is a ring then a ≤ b ⇒ r □ a ≤ r □ b for all a, b and r ∈ R implies s □ a ≥ s □ b for all a, b ∈ H and s ∈R. (c) If R is the positive cone of a linearly ordered ring R and H is the positive cone of a linearly ordered group H then the external composition can be continued (extended) in a unique way on R x H such that H is a linearly ordered module over R. In fact result (1) is useful in the study of Algebraic path problems [2].

Since the publication of the Newman-Penrose (“NP”) equations in 1962 they have been regarded as simply a different version of the Einstein field equations (“EFEs”). This paper reports the fact that symmetry methods can be employed to reduce the complexity of the NP equations, reformulated in terms of the elements of the metric tensor rather than the spin coefficients, and to derive the exact solution in the reference frame of an observer who is in radial free fall through the external vacuum gravitational field of an isolated, non-rotating, spherically symmetric gravitating body. While the domain of the solution is confined to the axis along which the observer falls, it can be directly compared to the Schwarzschild solution and is shown to differ from that solution.Since the publication of the Newman-Penrose (“NP”) equations in 1962 they have been regarded as simply a different version of the Einstein field equations (“EFEs”). This paper reports the fact that symmetry methods can be employed to reduce the complexity of the NP equations, reformulated in terms of the elements of the metric tensor rather than the spin coefficients, and to derive the exact solution in the reference frame of an observer who is in radial free fall through the external vacuum gravitational field of an isolated, non-rotating, spherically symmetric gravitating body. While the domain of the solution is confined to the axis along which the observer falls, it can be directly compared to the Schwarzschild solution and is shown to differ from that solution.

The paper introduces a new approach to magnify vibration responses of an object. In general, the higher the frequency of vibration, the lower the amplitude of displacement, so the response can be loaded by noise. The aim of this paper is to present practical application of the proposed approach in 3D digital image correlation method. This method uses two high speed cameras to measure displacements of the object. The phase-based motion magnification technique is used to magnify motion in captured image frames. Magnified frames are subsequently correlated to acquire displacement and deformation fields of the object. By this way, the amplified response is obtained. This approach also can be useful when the level of excitation is too low. The paper describes the experimental measurement that is based on the following procedure. As first the experimental modal analysis is performed and one of vibration mode is chosen for the further analysis. Thereafter, the object is excited using an acoustic exciter by harmonic signal with frequency of the chosen mode at two different amplitudes of excitation. The measurement with the higher level excitation is considered as the reference one. The responses acquired under the low level of excitation are subjected to the given procedure to magnify vibration motion. Results of both measurements are compared and commented.

This paper constructed a new high speed and power density servo motor design scheme based on magnetic pole eccentricity proposed according to the requirements of electrical performance parameters. The analytical formulae were deduced in view of the theory of thick-walled elastic cylinders and the actual model by analytical calculations and finite element calculations. The structure strength of permanent magnet was analyzed. Furthermore, comprehensively comparing and analyzing the calculation results of the two methods verify the accuracy of the analytical calculation method and the rationality of the permanent magnet structure design. In brief, this paper provides a reference for the design of high-speed motor magnetic pole eccentricity.

The paper deals with homogenization of the generalized Poisson–Nernst–Planck problem stated in the disconnected domain composed of solid and pore phases. The nonlinear cross-diffusion transport equations are coupled with the Stokes flow model. At the interface between two phases, field variables are discontinuous allowing jumps, and nonlinear interface conditions describing electro-chemical reactions are taken into consideration. The first-order asymptotic corrector corresponding to the non-periodic interface data is derived rigorously and justified by residual error estimates within the homogenization procedure.The paper deals with homogenization of the generalized Poisson–Nernst–Planck problem stated in the disconnected domain composed of solid and pore phases. The nonlinear cross-diffusion transport equations are coupled with the Stokes flow model. At the interface between two phases, field variables are discontinuous allowing jumps, and nonlinear interface conditions describing electro-chemical reactions are taken into consideration. The first-order asymptotic corrector corresponding to the non-periodic interface data is derived rigorously and justified by residual error estimates within the homogenization procedure.

Applications of the diffuse optical tomography to a thyroid cancer detection have been investigated by using the optical contrast. For the application, one needs to investigate effects of two factors (the diffusive reflection and refractive-index mismatch) at the tissue-trachea interface on light propagation in the human neck. In a previous work, the human neck was modeled as a two-dimensional circular heterogeneous medium consisting of a background medium and a circular void region, and the effects of the two factors at the medium-void interface in the simple heterogeneous medium were investigated using the time-dependent radiative transfer equation (RTE) in the time domain (TD). Nevertheless, the effects of the two factors in the continuous wave (CW) is still unclear because a crossover from the ballistic light to diffusive light in the CW differs from that in the TD. In this paper, we investigated the effects of the two factors using the steady-state RTE in the CW for the simple heterogeneous medium. The numerical results showed that the diffusive reflection dominated over the refractive-index mismatch at the medium-void interface even when the void region was located near the light source, where light is scattered anisotropically. The results in the CW were quite different from those in the TD, where the strong effects of the refractive-index mismatch were observed. The difference in the effects between the TD and CW is probably ascribed to a fact the refractive index influences in a shorter time scale compared to the time period for the average in the TD.Applications of the diffuse optical tomography to a thyroid cancer detection have been investigated by using the optical contrast. For the application, one needs to investigate effects of two factors (the diffusive reflection and refractive-index mismatch) at the tissue-trachea interface on light propagation in the human neck. In a previous work, the human neck was modeled as a two-dimensional circular heterogeneous medium consisting of a background medium and a circular void region, and the effects of the two factors at the medium-void interface in the simple heterogeneous medium were investigated using the time-dependent radiative transfer equation (RTE) in the time domain (TD). Nevertheless, the effects of the two factors in the continuous wave (CW) is still unclear because a crossover from the ballistic light to diffusive light in the CW differs from that in the TD. In this paper, we investigated the effects of the two factors using the steady-state RTE in the CW for the simple heterogeneous medium. T...

Let X be a finite set of m elements. Let On(X) be the set of all n-ary operations on X. On On(X), it is defined operation “+” with (f+g)(x¯)=f(g(x_1),g(x_2),…,g(x_n)), for all f, g ∈ On(X) and x¯=(x1,x2,…,xn) ∈ Xn, so that (On(X), +) is a semigroup. In this paper we give some properties of idempotent elements, regular elements, coregular elements, left zero elements and right identity elements on On(X). Moreover, from this properties, we provide some properties of nontrivial subsemigroups of the semigroup (On(X), +).Let X be a finite set of m elements. Let On(X) be the set of all n-ary operations on X. On On(X), it is defined operation “+” with (f+g)(x¯)=f(g(x_1),g(x_2),…,g(x_n)), for all f, g ∈ On(X) and x¯=(x1,x2,…,xn) ∈ Xn, so that (On(X), +) is a semigroup. In this paper we give some properties of idempotent elements, regular elements, coregular elements, left zero elements and right identity elements on On(X). Moreover, from this properties, we provide some properties of nontrivial subsemigroups of the semigroup (On(X), +).

The basic problems of the previous generations of the mirror traps, like MHD and kinetic stability and longitudinal thermal conductivity, were successfully solved, making it possible to reach temperatures much higher than it was supposed by the sceptics in early 2000-s. This paper sums up the experiments on magnetic mirrors in the Budker INP and their contribution to the next-step linear machine efforts. Current program of the linear machines for fusion exploits both experimentally verified and recently proposed methods of the longitudinal particle and energy loss suppression. Linear machine with improved enough longitudinal confinement is suitable for fusion with advanced fuels. Ways of the suppression are verified at GDT (gas-dynamic), GOL-NB (multiple-mirror), SMOLA (helical) and CAT (diamagnetic) devices. Next-generation GDMT project includes all the discussed ideas.The basic problems of the previous generations of the mirror traps, like MHD and kinetic stability and longitudinal thermal conductivity, were successfully solved, making it possible to reach temperatures much higher than it was supposed by the sceptics in early 2000-s. This paper sums up the experiments on magnetic mirrors in the Budker INP and their contribution to the next-step linear machine efforts. Current program of the linear machines for fusion exploits both experimentally verified and recently proposed methods of the longitudinal particle and energy loss suppression. Linear machine with improved enough longitudinal confinement is suitable for fusion with advanced fuels. Ways of the suppression are verified at GDT (gas-dynamic), GOL-NB (multiple-mirror), SMOLA (helical) and CAT (diamagnetic) devices. Next-generation GDMT project includes all the discussed ideas.

Spherical Tokamak (ST) path to Fusion has been proposed [1] and experiments on STs demonstrated feasibility of this approach. Advances in High Temperature Superconductor technology [2] allows significant increase in the toroidal field (TF) which was found to improve confinement in STs. The combination of the high normalised plasma pressure, β, which has been achieved in STs [3], and high TF that can be produced by HTS TF magnets, opens a path to lower-volume fusion reactors, in accordance with the fusion power scaling proportional to β2Bt4V. Modular approach then becomes an alternative to high power, GW-scale Fusion reactors [4,5]. Feasibility of low-power compact ST reactor module and physics and engineering challenges of the accelerated, ST path to Fusion Power are discussed in this paper, on example of the first our prototype on this route, high-field compact spherical tokamak ST40.Spherical Tokamak (ST) path to Fusion has been proposed [1] and experiments on STs demonstrated feasibility of this approach. Advances in High Temperature Superconductor technology [2] allows significant increase in the toroidal field (TF) which was found to improve confinement in STs. The combination of the high normalised plasma pressure, β, which has been achieved in STs [3], and high TF that can be produced by HTS TF magnets, opens a path to lower-volume fusion reactors, in accordance with the fusion power scaling proportional to β2Bt4V. Modular approach then becomes an alternative to high power, GW-scale Fusion reactors [4,5]. Feasibility of low-power compact ST reactor module and physics and engineering challenges of the accelerated, ST path to Fusion Power are discussed in this paper, on example of the first our prototype on this route, high-field compact spherical tokamak ST40.

In this paper we present conservation laws for a (3 + 1)-dimensional extended Zakharov-Kuznetsov equation which describes an isothermal multicomponent magnetised plasma and can also be obtained by using the perturbation method in the propagation of dust.In this paper we present conservation laws for a (3 + 1)-dimensional extended Zakharov-Kuznetsov equation which describes an isothermal multicomponent magnetised plasma and can also be obtained by using the perturbation method in the propagation of dust.

Induction heating is a process of heat generation which uses metal conductors and the Joule effect. The induction heating process has many applications in industry, such as metal melting, preheating for forging operations, hardening, and welding. A model of induction heating is given by a coupled system of partial differential equations relating temperature field and magnetic potential. Precisely, a coupled system of Maxwell and heat equations is given in the workpiece, while in the exterior domain the Laplace equation for the magnetic potential is formulated. Finally, nonlinear boundary condition for the heat equation, transmission conditions and asymptotic condition for the magnetic potential are given. Solution of such coupled multifield problems requires advanced coupled numerical methods. Therefore, in this paper we present a coupled numerical approach connecting Finite Difference Method and discrete potential theory. The use of discrete potential theory is motivated by the fact that asymptotic conditions are satisfied exactly on the discrete level. Thus, a general scheme for the coupled numerical method is presented in this paper.Induction heating is a process of heat generation which uses metal conductors and the Joule effect. The induction heating process has many applications in industry, such as metal melting, preheating for forging operations, hardening, and welding. A model of induction heating is given by a coupled system of partial differential equations relating temperature field and magnetic potential. Precisely, a coupled system of Maxwell and heat equations is given in the workpiece, while in the exterior domain the Laplace equation for the magnetic potential is formulated. Finally, nonlinear boundary condition for the heat equation, transmission conditions and asymptotic condition for the magnetic potential are given. Solution of such coupled multifield problems requires advanced coupled numerical methods. Therefore, in this paper we present a coupled numerical approach connecting Finite Difference Method and discrete potential theory. The use of discrete potential theory is motivated by the fact that asymptotic condi...

The most recent Nijmegen extended-soft-core ESC16 model for the baryon-baryon (BB) interactions of the SU(3) flavor-octet of baryons (N, Λ, Σ, and Ξ) is presented. The ESC model ESC16, as well as its predecessors ESC08 and ESC04, describe the nucleon-nucleon (NN), hyperon-nucleon (YN), and hyperon-hyperon (YY) interactions in a unified way using broken SU(3) symmetry. In this paper we outline the differences between ESC16 and ESC08c.The parameters of the ESC models are established in a simultaneous fit to the NN and YN data, taking into account information about ΛΛ, ΞN, and Λ-hypernuclei in the form of constraints. In particular, the experimental indications for ΛΛ-attraction, Ξ-nuclear and Σ-nuclear well-depth were taken into account as much as possible. About 25 physical coupling parameters and 8 cut-off and diffractive masses, were searched. The obtained OBE-couplings and the F/(F+D) ratios can be well understood in the context of the quark-antiquark pair creation (QPC) mechanism.The fit of the ESC-models to the NN- and YN- scattering data with a single set of parameters has achieved excellent results for the NN and YN data, and for the YY data in accordance with the experimental indications for ΛΛ. In the case of the most recent ESC model, called ESC16, the achievements are: (i) For the selected 4313 pp and np scattering data with energies 0 ≤ Tlab ≤ 350 MeV, the model reaches a fit having χ2/Ndata = 1.10. (ii) The deuteron binding energy and all of the NN scattering lengths are fitted very nicely. (iii) The YN data are described very well with χ2 /Ndata = 1.11, giving at the same time good descriptions of the Λ, Σ, and Ξ nuclear well-depths. (iv) The model has no bound states for S = −1,−2,−3,−4. (v) The nuclear saturation, and well-depths UΣ, UΞ require important contributions from three-body forces.The most recent Nijmegen extended-soft-core ESC16 model for the baryon-baryon (BB) interactions of the SU(3) flavor-octet of baryons (N, Λ, Σ, and Ξ) is presented. The ESC model ESC16, as well as its predecessors ESC08 and ESC04, describe the nucleon-nucleon (NN), hyperon-nucleon (YN), and hyperon-hyperon (YY) interactions in a unified way using broken SU(3) symmetry. In this paper we outline the differences between ESC16 and ESC08c.The parameters of the ESC models are established in a simultaneous fit to the NN and YN data, taking into account information about ΛΛ, ΞN, and Λ-hypernuclei in the form of constraints. In particular, the experimental indications for ΛΛ-attraction, Ξ-nuclear and Σ-nuclear well-depth were taken into account as much as possible. About 25 physical coupling parameters and 8 cut-off and diffractive masses, were searched. The obtained OBE-couplings and the F/(F+D) ratios can be well understood in the context of the quark-antiquark pair creation (QPC) mechanism.The fit of the ESC-mod...

We numerically studied light propagation in the two-dimensional human neck model using the time-dependent radiative transfer equation (RTE) for an application of diffuse optical tomography to a thyroid cancer detection. Because complicated light propagation is induced by a heterogeneity of the human neck, highly forward-peaked scattering of light by the tissue volumes except the trachea, and the refractive-index mismatch at the trachea-tissue interface and external boundary, one needs a large number of discrete angular directions (ND) for the RTE calculations, meaning high computational loads. Toward a construction of an efficient numerical scheme of the RTE, in this paper, we focused on a numerical treatment of the highly forward-peaked scattering of light. Then, we investigated numerical errors of the RTE calculations using two kinds of renormalization approaches to the highly forward-directed phase function: the conventional Liu’s approach and developed approach by some of the authors. The investigations showed that the developed approach provided accurate results of the RTE calculations around the peak time regimes even when ND decreased. In the decay time regime, however, the developed approach provided less accurate results because in that regime the refractive-index mismatch at the trachea-tissue interface dominated in the light propagation over the highly forward-peaked scattering.We numerically studied light propagation in the two-dimensional human neck model using the time-dependent radiative transfer equation (RTE) for an application of diffuse optical tomography to a thyroid cancer detection. Because complicated light propagation is induced by a heterogeneity of the human neck, highly forward-peaked scattering of light by the tissue volumes except the trachea, and the refractive-index mismatch at the trachea-tissue interface and external boundary, one needs a large number of discrete angular directions (ND) for the RTE calculations, meaning high computational loads. Toward a construction of an efficient numerical scheme of the RTE, in this paper, we focused on a numerical treatment of the highly forward-peaked scattering of light. Then, we investigated numerical errors of the RTE calculations using two kinds of renormalization approaches to the highly forward-directed phase function: the conventional Liu’s approach and developed approach by some of the authors. The investigatio...

Mufflers represent devices used to reduce sound and pulsations for internal combustion engines and other equipment like volumetric compressors. Depending on application they are designed to reduce low, medium or high frequency pulsations. The main design is represented by acoustic filters which use the acoustic analogy method. Dealing with low frequency pulsations this type of filters result in bulky constructions. The use of metamaterials results in a more compact design for these type of mufflers. This paper investigates by numerical simulations the transmission loss (TL) of such muffler based on acoustic black hole (ABH) metamaterial principle. In the first part of the paper the FEM results are compared with the acoustic measurements performed on an adapted impedance tube, in order to validate the model. In the second part the influences of the geometric parameters (length of the muffler, lamellae depth and thickness) will be investigated. The comparative analysis between the FEM and the measured results indicates good agreement. The geometric parameters analysis highlighted that the acoustic attenuation can be increased by using a long muffler.

This paper presents the method of estimating the spatial thickness of a stationary or flowing liquid film by the optical method based on the estimation of the monochromatic light beam attenuation when it propagates in an absorption medium, better known as the Beer–Lambert–Bouguer Law, which is also used in infrared spectroscopy method. The results of the test experiments show that the Beer–Lambert–Bouguer Law is correct if the light intensity is replaced by the value of the brightness component. An estimate of the brightness component is easy to obtain based on the analysis of digital photographs or video recording, namely, by tuples of the value of gray gradation (brightness) calculated using one of the mathematical models for the color representation. For unsteady flows of a liquid film, analyzing the extremum of the autocorrelation function from the displacement of the local area between two adjacent video frames, it is possible to estimate the volume-average value of the flow velocity.

The paper deals with the issues of mathematical modeling of gas-dynamic and thermophysical processes occurring in the internal (working) volume of the air heat curtain (AHC) with a tangential fan. The flow structure in the form of current lines, fields of pressure, temperature, and gas velocity at fan speeds 250 rpm and 1000 rpm are given. It is shown that the structure of the flow does not depend on the fan rotation speed, the speed profiles are self-similar, and the temperature field is invariant concerning the fan rotation speed. Thus, optimization of the air heat curtain structural elements can be carried out at the fixed value of impeller rotation speed, as it does not affect parameters of the output jet. As a result of numerical simulation, it was found that the area of the return flow is formed on the cut of the output diffuser, which significantly reduces the output air jet performance.

The arcticle gives a spatial gas-dynamic formulation of the backpressure problem, which describes the change in pressure in front of an accelerating projectile when it moves along the bore. This takes into account the geometry of the front of the projectile and its influence on the formation of the shock wave. An unsteady spatial flow of the displaced medium ahead of the projectile body without and taking into account the forces of viscosity is considered. The paper considers the solution to the problem of throwing a body using the energy of gunpowder combustion. The internal ballistics problem, which determines the dynamics of the projectile movement, is solved in terms of averaged parameters. A two-step Runge-Kutta scheme with a second order of accuracy is used to numerically integrate a system of ordinary differential equations in time. The control volume method is used for the numerical solution of the system of gas-dynamic equations. The gas parameters at the boundaries of the control volumes are determined using a self-similar solution to the problem of the decay of an arbitrary discontinuity. A comparison is presented of taking into account the backpressure as the pressure behind the detached shock wave, obtained from the analytical solution of the problem of the supersonic motion of a flat piston in a pipe at a constant velocity, and the pressure acting on the projectile, determined from the solution of nonstationary one-dimensional and spatial (axisymmetric) equations of gas dynamics. It was found that taking into account the viscosity practically does not affect the results of calculating the backpressure, while taking into account the shape of the front part of the projectile leads to a significant difference in the pressure fields behind the front of the shock wave compared to the solution in the framework of the one-dimensional formulation of the problem, where the shape of the front part of the projectile cannot be taken into account. It is concluded that this can significantly affect the results of modeling the ballistics of a shot at high throwing speeds.

In the present paper we consider the nonlocal boundary value perturbation problem { e2∂2u(t,x)∂t2−(a(x)ux(t,x))x+δu(t,x)=f(t,x),0

In this paper we present a numerical study of two streamwise supersonic vortices interaction. A pair of vortices was generated by two coaxial straight wings with sharp leading and trailing edges. Mach number of incoming flow was M∞ = 3. Two configurations are considered: a pair of co-rotating vortices and a pair of counter-rotating vortices. In the case of counter-rotating vortices the wings attack angle was 10 degrees. In the case of co-rotating vortices the attack angle of one of the wings was 10 degrees, the attack angle of other one was -10 degrees. Numerical data were obtained in the domain of 10 wing chords downstream from a wings axis by a computational model based on the URANS equations with SA turbulence model. Numerical simulations were performed on the hybrid supercomputing system K-60 at the Keldysh Institute of Applied Mathematics RAS using the developed software package ARES for 3D turbulent flows modeling on high performance computing systems. This work is a continuation of the series of author’s works dedicated to the supersonic wingtip vortices.

This paper presents a mathematical model and code-implemented engineering calculation technique that allow to study workflow inside a ramjet’s combustion chamber under dynamic variation of external and internal parameters: flight speed, angle of attack, and fuel mass flow rate. To assess adequacy of the mathematical model and the technique, a comparison is performed between results of internal ballistics calculations of a spaceplane’s ramjet obtained by aforementioned mathematical model and by numerical simulation in a computational fluid dynamics software package. This is tested for cruise flight conditions and for dynamic variation of flight parameters and fuel mass flow rate in a wide range. It shows that for a model subsonic flow combustion chamber a satisfactory correlation between these solutions is realized. Transient processes are stable and monotonous for all cases studied, registered oscillations of total pressure and temperature in relation to their stabilized values and weak overshooting have no effect on the engine’s output characteristics.

The paper provides a brief overview of recent computational studies of flow and heat transfer control by rotary oscillations of an infinite circular cylinder at a relatively broad set of imposed frequencies and amplitudes [1, 2]. A study for a previously unreachable high subcritical Reynolds number Re = 1.4 × 105 showed that the efficiency of this control method increases with Re concerning the issue of drag and lift reduction. High-frequency oscillations even lead to around 90 % reduction of the drag. However, the benefits for heat transfer enhancement is not that obvious as the bulk Nusselt number shows only small variations. At the same time its angular distribution around the cylinder becomes much more homogeneous due to oscillations which practically can prevent local overheats.

In this paper, we report our current progress on constructing the machinery to calculate the moment of inertia of a compact star in the Eddington-inspired Born Infeld theory. As a result of translating the metric functions from apparent metric to physical metric, we obtain that the resulting physical moment of inertia is shifted by a term that is linear to κ, one of the parameters of EiBI.

This paper aims to design a small-scale, compact supersonic wind tunnel nozzle using the method of characteristics and perform computational fluid dynamics (CFD) simulations to validate the design. The wind tunnel is designed to have a test section of 7cm × 7cm and a test section Mach number of 2.0. Simulations were performed for both 3D inviscid and viscous cases and it shows that for both cases, the obtained Mach number conforms with the design requirements. A further study on the effects of different pressure ratios, towards the position of shock waves, shows that an increase in the ratio would result the shock waves to shift downstream.

In this paper we wish to introduce the concept of tripolar fuzzy weak bi-ideal of a near ring and study some of its properties.

In this paper an attempt is made to solve the problem of the use of electromagnetic equations to determine the stress wave propagation in a visco-elastic finite thin rod of Maxwell Type in a magnetic field by using finite fourier sine transform and Laplace transforms.

Malaysia Youth Satellite (MYSat) is a scientific 1U CubeSat initiated by School of Aerospace Engineering Universiti Sains Malaysia (USM) in 2016. The objective of the MYSat mission is to measure accurate electron density and temperature in E-layer of the ionosphere by a CubeSat. This mission was driven from a study which reported that Earthquake precursors could be analyzed from the ionosphere. Electron temperature and density probe (TeNeP) was the selected scientific instrument for MYSat. This instrument develops a technique by measuring the shift of electric floating potential (ΔVf) characteristics of an electrode immersed in plasma. The ΔVf characteristic of the plasma will then be retrieved from the instrument where the plasma’s electron density (ne) together with the temperature (Te) can be acquired. The TeNeP instrument has been proven not affected by the satellite potential variation effects, which is a common problem for electron measurements onboard small satellites, especially CubeSats. Therefore, the accurate Te and ne measured by MYSat could contribute to the on-going research regarding ionospheric physics and possible Earthquake precursor effects. An already developed TeNeP circuit based on a 2U platform has been redeveloped for MYSat’s 1U based platform. In this paper, several performance tests to the TeNeP generator circuit in the preparation of the MYSat will be shown and discussed.

The law states that energy and time want to be or remain in equilibrium. At the time of the big bang, this time was constricted so much, and singularity was present. The whole universe came and expanded from that singularity, the energy was produced and cosmic inflation of the time limit of 10−36 s happened. However, why did this happen? Why did energy at that time expanded and evolved into the universe as we know it to be present? Also, why the only universe as we know it as it is and not something else, why did the energy did not evolve into something else? These are some questions which we will explain and answer using the law of energy time equilibrium. We have discussed the properties of time correlation with energy for several systems that are simple enough to illustrate the extraction of energy through fluctuation and distortion of equilibrium. We develop a succinct theory of extraction of electrical energy from a classical system subjected to cyclic change between electric and magnetic energy via virtue of fluctuation of energy-time-equilibrium. We show the range inside of which energy-time-equilibrium is established, outside of which it gets distort or disturbed. To sustain the system and extracting the electrical energy, we introduce an engineering machine named Eklavya, which periodically comes out and goes inside of the energy density (with respect of time) sphere of range of equilibrium. In this paper we will not give detailed information about Eklavya.

Photon, due to the ‘continuous and periodic action’ about its travel line from the emitting atom hints the ‘continuous and periodic function’ about its travel line and consequently the wave equation. The travel line is one with respect of which the measurements of all length-time observables are done, for instance wavelength, frequency as time inverse etc. It is the continuous and periodic function (or action) of photon that concern the light as electromagnetic wave on single photonic level. Here within this paper the wave equation of single photon is obtained by the consideration of its qubit complex coefficients as function to which the calculus approach ‘differentiation’ applied like to any other ordinary function.

This paper deals with the frequency response of swirl flow behind an axial swirler. Vortex breakdown resulting in the formation of a precessing vortex core is considered. The influence of the swirl intensity and the nozzle confinement effect on the frequency response of the PVC is studied. Regimes with the presence of PVC were determined using two microphones. The Strouhal number depends linearly on the swirl parameter and weakly on the Reynolds number. The measurement results are used to derive an empirical dependence of the Strouhal number on a modified geometric swirl number. This allows a generalization of the frequency characteristics of swirling flows with a PVC for the class of axial vane swirlers, which are most widely used in engineering.

In this paper an attempt is made to solve the problem of unsteady laminar motion of a dusty viscous incompressible fluid through concentric circular cylinder under time dependent pressure gradient an attempt is made to determine the velocities the fluid to and the dust particles by using finite Hankel transform and Laplace transforms methods.

In this paper, the problem of entropy production on adiabatic propagation of strong spherical imploding shock waves in a dusty gaseous atmosphere having solid body rotation, has been carried out by using CCW theory. The gaseous medium is assumed to be seeded a large number of small spherical solid particles of uniform size. The solid particles are also assumed to be inert and uniformly distributed in the medium. The strength of overtaking waves is estimated under the assumption that both C+ and C− disturbances propagate in the region of same density distribution. Maintaining equilibrium flow conditions, analytical expressions for change in entropy and temperature across the shock front have been derived for both freely propagation as well as under the effect of overtaking disturbances, for the power varying initial density distribution. Neglecting the effect of coriolis forces, the influence of overtaking disturbances on the variation of change in entropy and temperature with propagation distance, mass concentration of solid particles in the mixture, the ratio of solid particles to the initial density of gas, initial angular velocity and the density parameter have been calculated numerically and discussed through graphs. It is found that dust presence in the gases medium has significant effects on the entropy production and temperature. It is shown that the entropy production and temperature are further increasing across the shock in presence of overtaking disturbances. The results obtained here been compared with those for freely propagating shock as well as for the dust free ideal gas.

The current paper presents a semi-analytical solution for the problem of swirl decay under laminar flow in a circular duct with constant value of the radial velocity at the inlet. The swirl velocity equation is solved by the separation of variable technique. Based on the eigenvalues and eigenfunctions corresponding to the solution of main problem it is found that the slowest breakdown processes of eddy structures under laminar viscous flow are described by the exponential function.

Electromagnetic ion cyclotron (EMIC) waves with temperature anisotropy were studied in Saturn’s non-uniform magnetic layer. After the kinetic method, after injecting a cold plasma beam into the Saturn system, the growth rate of the EMIC wave was theoretically studied. An expression of the dispersion relation is drawn by using the method of the characteristic solution. Therefore, in this paper, a ring distribution is used instead of the usual Maxwellian distribution. The focus of this study is on the oblique propagation of EMIC waves, whose temperature anisotropy, ion energy density, and propagation angle vary with the direction of the magnetic field. The study found that these parameters support the growth rate of EMIC waves in the Saturn magnetosphere. Numerical analysis also shows that as the number density of cold plasma and the number of thermal plasmas increase, the growth rate of EMIC waves also increases. These results apply to the application of space plasma environments and magnetospheric systems for detailed comparison of planetary studies.

In this paper, we propose Two Dimensional Photonic Crystal (2DPC) square lattice structure to design Channel Drop Filter (CDF) for optical communication networks. The proposed filter is designed using dual curved Photonic Crystal Ring Resonator (PCRR). The Photonic Band Gap (PBG) is calculated by Plane Wave Expansion (PWE) method. The 2DPC square lattice periodic arrays of dielectric rods have been investigated by Finite Difference Time Domain (FDTD) method. The number of rods in Z and X directions are 21 and 20, respectively with lattice constant a = 0.540 µm and rod radius r = 0.1 µm. The Filter has been optimized for telecommunication wavelengths λ = 1.551 µm with refractive indices 3.31 of materials Al0.4Ga0.6As. Further, the investigation is extended for study the effect of scattering rods radius, which leads to shift of resonant wavelength. The proposed structure is useful for CWDM optical communication systems and photonic integrated circuits which is ultra-compact device.

Superconductors are demonstrated to profoundly differ in arrangement yet elusive and mysterious. To understand the Josephson Effect, it is advisable to first acquire some notion about the origin of the superconductivity. Macroscopically, superconductivity manifests itself as a lack of resistance, so that the current flows with no obstacles. The practical applications of superconductivity are consistently improving each year. However, the real utilization of superconducting devices is constrained by the way that they should be cooled to low temperatures to move toward becoming superconducting. The revelation of high-Tc superconductors broadens the feasible application of superconductors. The Josephson Effect has enabled the advancement of unique electrical devices and systems including SQUIDs, quantum computers, analog to digital (A/D) converters, Josephson voltage standard, THz emitters and detectors, single flux quantum devices, etc. In this research paper, we studied the Superconducting materials, its characteristics and applications in physics.

The dispersion plays an important role in pulse propagation in an optical fiber. The effect of higher order dispersion terms are generally neglected for pico second pulse propagation. In this paper we have tried to discuss the propagation length upto which the third order dispersion (TOD) parameter may be neglected. Beyond this length the ignorance of this parameter is not possible as it may affect the pulse shape. Semiconductor Bloch equations are applied to determine the Polarization induced in the medium due to incident Gaussian pulse. The analysis of induced polarization is made by Non linear Schrodinger equation. To represent the pulse propagation behavior linear partial differential equation is used. The results of the numerical calculations provide a support for the fact that the third order dispersion parameter in an optical fiber may be neglected only upto a specified length depending upon the input pulse width.

This paper discusses the quality of GPS antenna signals on the effect of rocket attitude using SDR (Software Defined Radio). The antenna is mounted on the surface of the rocket tube, where the rocket’s position is horizontal, vertical, and tilted. The quality of the GPS signal is determined by the number of satellites that can be detected and the received signal strength. The experimental results show that when the rocket is horizontal and the antenna is on the upper surface, the signal is strongest and the number of satellites detected is more than the other positions (>4 satellite). The signal is weakest when the rocket is horizontal and the antenna position is on the lower surface so that the number of satellites detected is least.

The encounter between Voyager and Saturn’s environment reveals the presence of electromagnetic ion cyclotron waves (EMIC) in the magnetosphere of Saturn. Cassini provides evidence of dynamic particle injection in Saturn’s internal magnetosphere. Previous theoretical studies have suggested that EMIC waves may explain the loss of relativistic electron populations. However, recent observations indicate that although the EMIC wave is responsible for the significant loss of super-relativistic electrons, the relativistic electron population is almost unaffected. In this paper, we study the effects of EMIC waves and relativistic particles on these waves in the plasma, which propagate obliquely relative to Saturn’s magnetic field. The particles are assumed to be trapped and follow ring distribution function. Using the kinetic approach, the expressions of dispersion relation and growth rate are derived. Various parameters affecting the growth of EMIC waves has been studied. The effect of drift velocity has also been studied in this case.

The paper presents a method of transient temperature and stress-state estimation in thick-walled pressure components. If complex physical phenomena inside the component make it difficult to define the boundary condition on its inner surface, an inverse boundary problem emerges. The proposed method makes it possible to solve the problem using “measured” temperature histories in easily accessible points located on the component outer surface. The method stability and accuracy are shown by comparing the inverse method results and the exact values obtained from the direct method. The presented method does not require drilling holes for sensors in pressure element walls.

In this paper, a quantitative analysis of observed parameters is taken into account that influences superconducting state of Al and C doped MgB2. The analysis assumes a three square well model with three interactions namely, the Coulomb’s, the electron phonon and the electron-charge fluctuations. The relevant energy gap expressions in the formalism are solved imposing experimental constraints on their solutions. It is found that the indirect-exchange formalism provides a unique set of electronic parameters [electron-phonon (λσσph), electron-charge fluctuations (λσσpl), electron-electron (μσσ) and Coulomb screening parameter (μσσ*)]. It is shown that the addition of electron to Mg1-xAlxB2 [Mg(B1-yCy)2] through the partial substitution of C for B and Al for Mg results in the loss of superconductivity.

This paper contains theoretical study of (Z)-4-(4-hydroxybenzylidene)-3-methylisoxazol-5(4H)-one. We have performed a comprehensive quantum chemical analysis with the help of combination DFT/B3LYP method and basis set 6-311++G(d, p). HOMO-LUMO and MESP plots used to describe Electronic properties of the compound. Prominent vibrational modes have been calculated and assigned for the vibrational infrared spectrum of the compound. The study provides more details of the compound for various use and pharmacological importance.

In this paper, mode generation based on an elliptical core few mode fiber (EC-FMF) is devised through an inverse function, designed using split step beam propagation method (BPM). The undesired modes from an EC-FMF are eliminated through an appended waveguide computed from the inverse phase of undesired modes. The EC-FMF may be used as an all-optical switch.

The present paper provides vibration analysis of functionally graded piezoelectric (FGP) actuator due to longitudinal piezoelectric coupling coefficient. In this regard, beam type geometry is taken into consideration. It is assumed that the electric potential has sinusoidal variation along the axial direction. The electro-mechanical properties of Timoshenko beam are supposed to change continuously throughout the thickness based on power law model. The governing equations and end conditions for FGP beam are derived using Hamilton’s principle. A mathematical modeling for clamped-clamped end condition is being obtained. Numerical results are presented to demonstrate the effect of various parameters on natural frequencies of FGP beam.

The different types of magnetic materials used for the rotor of Permanent Magnet Synchronous Motor (PMSM) and their impact on torque output due to respective change in torque output are analyzed in this paper. Also the effect of temperature rise in magnet and the consequences over the flux linkages are addressed. The simulation model of basic vector control method of PMSM has been made in order to know the actual impact and overall performance of the drive using MATLAB-Simulink.

Tamil Nadu Physical Education and Sports University (TNPESU) had a wind tunnel facility to study the forces and moments acting on the different balls in the rotation through a six-axis strain gauge. In this paper, the effect of the Magnus on the Cricket ball, Tennis ball, Baseball, Hockey ball and Golf ball is studied. The variation of Coefficient of Lift [CL], Coefficient of Drag [CD], Coefficient of Side force [CS], Coefficient of Roll moment [CRM], Coefficient of Pitch moment [CPM] and Coefficient of Pitch moment [CPM] of the static and rotational in both Clockwise and Anti-Clockwise condition. This data will give an insight into the ball performance in the spin and can be used in the sports effectively.

Skew cyclic codes over Bk = 𝔽pr [v1, …, vk]/〈vi2 − vi, vivj – vjvi〉 have been studied by Irwansyah et al in 2018. In this paper we use B1 = 𝔽p2 [v]/〈v2 – v〉 and the Gray map φ : B1→𝔽p22 defined by φ(a + bv) = (a, a + b) for all a + bv ∈ B1 and extend φ to Φ : B1n→𝔽p22n. If C is a skew cyclic code over B1, we can get Φ(C) ⊆ 𝔽p22n a skew cyclic code if n is odd and a skew 2-quasicyclic code if n is even. Then by using the map S introduced by Ezerman et al in 2011, we get a (4n, p2k, 2d) additive code over 𝔽p2 and we use this to construct an additive asymmetric quantum code.

Let G = (V, E) be a finite and simple graph with vertex set V (G) and edge set E(G), having order p and size q. A graph G is called super edge-magic if there exists a bijection f : V(G) ∪ E(G) → {1, 2, …, p + q} such that f (V(G)) = {1, 2, …, p} and f (u) + f (uv) + f (v) = k, for every edge uv ∈ E(G). The super edge-magic deficiency of a graph G, denoted by μs(G), is either the minimum nonnegative integer n such that G ∪ nK1 is super edge-magic or +∞ if there exists no such n. In this paper, we study the super edge-magic deficiency of forests where its components are subdivided stars or paths.

In the H-mode discharges with the neutral beam heating (NBI) in the Globus-M tokamak the sawtooth oscillations are triggering the edge localised modes (ELM) onset. The triggered ELMs have the magnetic oscillation precursor less than 0.2 ms before the onset with the typical island rotation frequency. The paper discussing the peeling-ballooning (P-B) destabilisation caused by the current density profile broadening due to partial reconnection.

In this paper we present conservation laws for a (1+1)-dimensional double dispersion equation which was formulated as a mathematical model of the propagation of dispersive waves in a wide variety of circumstances.

We discuss L=0 vs L=2 couplings, symmetries of the pairing interaction for neutrons and protons, and the Jmax interaction. We show that certain schematic interactions yield exponentially decreasing transition strengths.It is a pleasure to be able to contribute to proceedings honoring this milestone of Franco Iachello’s career. We will start with what may be regarded as early elementary precursors to his seminal papers with Akito Arima and others [1,2] on the interaction boson approximation -IBA and IBM. Then, as a change of pace we will discuss most recent work where we focus on matrix models of strength distributions for which there are many problems that are not yet understood.