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Assesment of minor rivers flood-plain and stream-way complex condition (case study of the Berezhnytsya River, Dniestr basin)

100%

Kovalchuk I. P. , Mykytchyn O. I. , Andreychuk Y. M. , Ivanov E. A. , Zhdanyuk B. S.

2016

tom Vol. 4, No. 2

61--68

The methodological and practical issues in respect of assessment of the flood-plain and stream-way complex of the Berezhnytsya river are presented in the article. Researched river is one of the Ukrainian Carpathians minor rivers and constituted the right-bank tributary of the Dniester river. The presented study typify the stream-way segments. Furthermore were shown identification of the reasons of decreasing the qualitative characteristics of the Berezhnytsya flood-plain and stream-way complex. The set of works to stop processes that are destructive for the river and its ecosystem should be made.

Methods of fractal analysis and phase trajectories for the improvement of identification of complex technical systems

100%

Chovnyuk Y. V. , Gumenyuk Y. O. , Djachenko L. A. , Ivanov E. A. , Kravchyuk V. T.

Zeszyty Naukowe. Quality. Production. Improvement

2019

tom No. 2 (11)

41--50

The procedure of the qualitative analysis of complex technical systems is discussed. One may use such methods of analysis for time series characterized the functioning of such systems. These time serious aren’t confirmed the hypothesis of trend existence. One may use at this qualitative analysis the methods of nonlinear dynamics and the theory of chaos. The basis for similar researches is Takens’s theorem. The randomness of the studied dynamical system as the model of the complex technical system given by time realizations is established by means of Lyapunov’s indicator. The state stability is estimated by Hausdorf’s fractal dimension and the fractality index. Visual evaluation of the time series was carried out by means of the phase trajectory restoration procedure. As a result of the analysis of the phase points in the phase space the split attractor is indicated, which gives the chance to speak about its bifurcation.

The evaluation of the current state of EHF-sensors quality in the technical systems and its improvement

86%

Chovnyuk Y. V. , Ivanov E. A. , Dovhaljuk V. B. , Shyshyna M. A. , Gumenjuk Y. O. , Sivak I. N.

Zeszyty Naukowe. Quality. Production. Improvement

2019

tom No. 2 (11)

26--40

In the article the function and the scale for the entropy evaluation of the current state of extremely high frequency (EHF-) sensors quality in the various technical systems which fits the requirements of universality and maximal independency from the human factor are offered. One may see such EHF-sensors for the analysis of the quick transformations of the biological liquids properties. It’s high lighted that the available methods of the determination of technical systems’ quality have essential flaws which consist in both subjectivism because the dominant role in the evaluation belongs to experts and legitimacy of providing them properties of universality which was proved by nobody. The scheme of EHF-sensor is analyzed for which one may create an analytical model. The problem of the fields’ determination at the working region of such sensor is discussed. The presented scheme is possible to use for the mathematical model and just for that part of the problem which is devoted to the transformation of the properties of the object. The results of calculation of components of electromagnetic field at the working space of EHF-sensor are discussed. One may estimate the sizes of this space. The offered function of the quality evaluation, the parameter of which is the quantity of own information of the explored sensor, provides the declared universality approach according to the principles of the information theory. The conformity to all requirements for the functions of the evaluation of the quality: continuity, monotonic and smoothness over the whole range of definition regardless of the probability distribution function, which is measured by the random value EHF-sensor was proved. The proposed scale of the entropy evaluation of the quality fits to standard settings of the diagnostic of the technical systems and has three sub ranges which determine the state of the EHF-sensors: good state, up state, and down state. Unlike the existing psychophysical scales the offered scale has dynamic range of the evaluation so the limits of the sub ranges will automatically change depending on the regulatory and technical requirements for the state of the explored EHF-sensor. Such approach provides adaptation of the scale to specific requirements which gives a chance to evaluate the qualitative state of the object more reliably. The results of modeling of the qualitative state of the sensor are given. The possible practical application of the offered function and scale is usage in the systems of monitoring and diagnostic for determination of the current qualitative state of the explored technical system, as well.