Probability of erroneous reception of navigational radio signals under ionospheric disturbances

The work deals with the issues of the determination of the probability of frequency-selective fading (FSF) of navigational radio signals in satellite radio navigation systems under artificial ionosphere disturbances. The connection between the coherence band of the trans-ionospheric channel and the conditional size of ionospheric inhomogeneities is established. Based on the results of computer simulation, the threshold values of the Mean square deviation (MSD) of fluctuations of the total electron content in the inclined radio-line are determined, in which the probability of frequency-selective fading is hig

Development of the forecast model for management of the disbalance between the labor markets and educational services in the construction industry

In this article, the procedure of the development of the forecast model is described. Within the model based on expert assessment factors that affect the imbalance between labour markets and educational services in the construction industry have been identified. Graphical visualization of models in the form of graphs is presented. On this basis, scenarios of social and economic development of the region in this area (optimistic, realistic and pessimistic scenarios) are define

Advantages and Applications of Cryopreservation in Fisheries Science

Cryopreservation is a long-term storage technique to preserve the biological material without deterioration for extended period of time at least several thousands of years. The ability to preserve and store both maternal and paternal gametes provides a reliable source of fish genetic material for scientific and aquaculture purposes as well as for conservation of biodiversity. Successful cryopreservation of fish sperm have been achieved for more than 200 fish species and many fish species have been adequated for the purpose of cryobanking. Cryopreservation of fish embryo is not viable, mainly because of the same limitations as in fish oocytes, i.e., high chilling sensitivity and low membrane permeability. However, cryopreservation of isolated embryonic cells is another option for preserving both maternal and paternal genome. In this paper, an overview of the current state of aquatic species is followed by a discussion on the sperm, embryos, oocytes and embryonic cells - blastomeres