### Перегляд за автором "Zaichenko, O. B."

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Публікація Coaxial aperture sensor for assessing the state of biologica objects(2018) Panchenko, A. Yu.; Slipchenko, N. I.; Zaichenko, O. B.; Bondarenko, I. N.Показати більше Water is the main substance that makes living organisms. The state of any bioobject is characterized by the total amount of water in it and its distribution. In biological matter, water can be in two states, in the form of free water and water, associated with its macromolecules. The distribution of free water and water associated with molecules of biological matter determines its state. Therefore, the task of rapid assessment of water distribution is topical. The water molecule has a low mass and in the free state the molecules have a high relaxation frequency, which lies in the microwave range. The dipole moment of water has a high value. Therefore, at frequencies below the relaxation frequency, water has a high value of the dielectric constant. In the bound state, its electrophysical properties of water depend on the properties of the macromolecule in which it is embedded. Therefore, microwave methods and electrodynamic measurement sensors are effective means of operative measurements. They have a high speed, simple measurement procedure, do not require special preparation of samples, they allow performing non-destructive testing. Therefore, under certain conditions, they have advantages over other methods. However, the problems of using electrodynamic methods are caused by the indirect nature of the data obtained and the rather complicated process of determining the transfer function of the microwave sensor. The report presents a scheme of the microwave sensor, in which the generatrix coincides with the coordinate surfaces. For such a scheme, you can create a rigorous analytical model. Solving the task of describing fields in the working area of such a sensor allows determining the transfer function of the sensor. The presented scheme allows a principled possibility of further development. For example, in the presence of a mathematical model of changes in the properties of a bioobject under external influence. This will allow a numerical evaluation of the sensor parameters at the theoretical preparation stage. Such an approach will significantly reduce time costs and reduce the cost of design, prototyping and experimental development of specific designs.Показати більше Публікація Dielectric parameters measurement with the aid of microwave multimeter(2017) Miroshnyk, A. M.; Zaichenko, O. B.; Rozhnova, T. G.Показати більше Multiprobe microwave multimeters allow to measure dielectric permittivity of materials along with power, complex reflection coefficient and wavelenght, being universal devices. A method proposed for determining the permittivity of materials on the basis of the mode in the form of an integral equation that is distinguished by the use of the dyadic Green's function as the kernel of the integral equation, with the simplification by variational principles to obtain engineering formulas for calculation measurement uncertainty.Показати більше Публікація Higher Order Propagation Modes Error and Its Compensation(2012) Zaichenko, O. B.; Klyuchnik, I. I.; Martynenko, L. G.Показати більше The physical and mathematical and metrological model of higher order propagation modes in multiprobe microwave multimeter with three sensors was composed. The higher order propagation modes error estimation, which is proposed, minimizes error by shifting sensors from the middle of the waveguide broad wall to the periphery, without changing the distance between the sensors along the direction of energy propagation through the waveguide.Показати більше Публікація Investigation of the influence of generator signal higher order propagation components and ways of its compensating in the multiprobe microwave multimeter(2014) Miroshnik, M. A.; Kovalenko, M. A.; Zaichenko, O. B.Показати більше The physical and mathematical and metrological model of higher order propagation modes in multiprobe microwave multimeter with three sensors was composed. The higher order propagation modes error estimation, which is proposed, minimizes error by shifting sensors from the middle of the waveguide broad wall to the periphery.Показати більше Публікація Modelling of influences of sensor reflection on the accuracy of a microwavev reflectometer(2014) Klyuchnyk, I. I.; Miroshnik, M. A.; Tsekhmistro, R. I.; Warsza, Z. L.; Zaichenko, O. B.Показати більше In this paper the uncertainty component of a multisensor microwave reflectometer dependent on mutual reflections between sensors is described. One-line and two-lines arrangement of the set of sensor localization are considered. Adjacent sensors influence each other. The mathematical model of signal flow graphs of such a system was developed. The set of linear algebraic equations incorporating main reflections between sensors was worked out. The least squares method or Kalman filter for averaging the sensor signals with random distortions is used. The uncertainty of measuring the power by the multi-sensor reflectometer is estimated. The obtained results are discussed. The described methods of the uncertainty evaluation can be applied to automation of the multi-sensor reflectometer and in other multivariable measurements.Показати більше Публікація Multiprobe Microwave Multimeter Error Definition on Its Sensor Error Base(Publishing House ”Izvestiya Vuzov”, 2005) Volkov, V. M.; Zaichenko, O. B.; Yevdokimov, V. V.Показати більше This paper propose a new method of estimation of multiprobe microwave multimeter algorithms precision by mean of accumulation of partial error. The least square solution is used for variance and covariance matrix definition. The weighted coefficient is obtained from algorithms derivatives with respect to intermediate variable. Substituting the expression for standard deviation (variance) end weighted coefficient in formula for partial error accumulation we can compare different algorithms, study frequency properties of algorithms.Показати більше Публікація Multiprobe Microwave Multimeter Error Estimation A Priori(Kontrast Publishing Enterprise, 2004) Zaichenko, O. B.Показати більше At a functional design stage there is a necessity of a priori estimation of general error in connection with the requirement specification. Thus such elements and structural links should be selected, that the estimation has not left for limits by given one. Pursuant to a technique of general error definition it is necessary to know or to set limiting values of individual components of errors, their distribution functions and to distinguishing from them dominant ones, to study a capability of correction.Показати більше Публікація Multiprobe Microwave Multimeter Frequency Properties(Kontrast Publishing Enterprise, 2004) Zaichenko, O. B.Показати більше In this report the multimeter frequency properties, in supposition that sensor transformation coefficient in given frequency band is fixed, are considered. The aim of report is working out method for algorithm comparison. Multimeter has the mathematical description as systems of linearized equations relatively intermediate variables. The matrix of a system is written down through trigonometrical expression, which arguments are intervals between sensors, phase spacing is connected to frequency.Показати більше Публікація Multiprobe Microwave Multimeter Functional Design(Kontrast Publishing Enterprise, 2004) Volkov, V. M.; Zaichenko, O. B.Показати більше Multiprobe microwave multimeter is a new type of measurement device representing an automatic multichannel system consisting of a very high frequency unit with passing power sensors and a computing unit on the basis of the microcontroller or PC and is intended for measurement incident, reflected and passing power, module and phase of a termination reflection coefficient, executing generator and termination checking in an" hot" mode. The methodology of the working MMM design with equidistant sensors arrangement.Показати більше Публікація Passing Power Sensors and Multiprobe Microwave Multimeter on Its Base(SPIE, 2006) Volkov, V. M.; Nikitenko, O. M.; Zaichenko, O. B.; Zharko, Yu. G.; Isichko, A. L.Показати більше The mathematical modeling of thin wall waveguide heating process allows to determine the law of temperature field distribution on their surface. The new physical models of sensors on the absorbing wall principle in the coaxial transmission line were proposed and dissipative losses dependence on frequency in one, two and three layer absorbing wall was analyzed. Methods of calculation and designing of the both quasipoint and extended sensors, located on the narrow and wide waveguide walls were proposed: minimization of effective reflection.Показати більше Публікація Signal flow graph and alternative gain formula for multiprobe microwave multimeter(2016) Miroshnyk, M. A.; Zaichenko, O. B.; Butenko, V. M.Показати більше The article was shown and proved that the construction of the model in the form of signal flow graph for gain determination does not necessarily use the rule of non touching loop (the Maison rule) for defining gain from generator to sensors, and it can be successfully replaced by the matrix computation.Показати більше Публікація Systematization of the Formulas of the Resonance Ferrite Isolator Loss(2022) Zaichenko, O. B.; Zaichenko, N. Ya.Показати більше The problem is to systematize and improve the models of a resonance ferrite isolator in the rectangular waveguide for the antenna-feeder devices, generating, receiving, measuring microwave equipment containing ferrite decoupling devices: ferrite isolators and circulators. Therefore, a number of hypotheses were put forward, what the formula might mean. The difficulty lay in the presence in the formula of the product of trigonometric functions that can be attributed to frequency properties, which was taken as an initial hypothesis, which was not subsequently confirmed. The check included transformation of formulas using mathematical physics in terms of microwave electrodynamics, trigonometry and algebra. The beginning was the formula of the classics, similar to the formula of, accepted without proof. As it is known, for the main type of wave in a rectangular waveguide, the components of the magnetic field strength, obtained as a solution to the wave equation under the boundary conditions inherent in a rectangular waveguide. One component of the magnetic field strength is along the direction of wave propagation, and the second one is in the transverse direction in the section of the waveguide are proportional to the trigonometric functions cosine and sine with the same arguments. The equality of the components of the strengths is traditionally uses to find the plane of circular polarization where to place the ferrite isolator, and so the authors use this proportionality to trigonometric functions in their derivation, namely the formulas of trigonometric functions of a double angle, the basic trigonometric identity sine squared plus cosine squared is equal to one for replacing the propagation constants with trigonometric functions, this allows to get rid of radicals in the formulas, these radicals in the formula are due to the phenomenon of dispersion in a rectangular waveguide. The rest of the manipulations with the formula are the reduction of similar terms. Results. There was obtained analytical expressions for the losses of the resonant ferrite isolator in the forward and reverse directions, as well as the isolator ratio by strict mathematical transformations. There was performed such transformations. The ratios of the longitudinal propagation constant to the transverse propagation constant are replaced by the ratios of the trigonometric functions sine and cosine, since they are continuous as opposed to tangents and cotangents. Such a transformation allows to avoid square roots in the formula for the losses of the ferrite isolator in the forward and reverse directions, which are associated with the presence of dispersion in the waveguide, as in the formula for wavelength in the waveguide. The conversion is based on microwave electrodynamics. The formulas are used for the distribution of fields in a rectangular waveguide for the main type of wave. Further transformations consist in taking the common factor out of brackets and other arithmetic transformations. Тhrer was obtained results partially coincide with the well-known , the derivation of the formula was ob-tained for the first time, the studies carried out allowed us to reject the hypothesis that the product of cosines and sines in the loss formula of a ferrite isolator is a frequency characteristic, it appears as a result of arithmetic transformations. To take into account the frequency range, it is used that there is circular polarization at the middle frequency, there will also be circular polarization at the extreme frequency of the range, but the plane of circular polarization will shift in comparison with the position of the plane of circu-lar polarization at the middle frequency. That is, a peculiar system of two equations is obtained with respect to two positions of the polarization plane relative to the wide side of the rectangular waveguide section. The scientific novelty consists in systematization and generalization of the formulas of the loss of the resonance ferrite isolator, the connection between the formulas from different literature sources, both foreign and domestic, is proved, which saves time for researchers of ferrite isolators for the verification of the formula. It may be useful for teaching purposes and in optimization of the ferrite isolator design.Показати більше Публікація Wideband Multiprobe Microwave Multimeter(IEEE AP-S Publishing House ”Izvestiya Vuzov” (Kyiv, Ukraine), 2003) Volkov, V. M.; Zaichenko, O. B.Показати більше The device, sensors and mathematics permit us to get new results in precision, performance function linearity, long term stability characteristics and so on. A multimeter, for passing, incident, reflected power, reflection coefficient module, and phase and wavelength.Показати більше