Purpose: To estimate the corneal measurements using Scheimpflug camera in patients with diabetes mellitus.Methods: Twenty five diabetic patients were prospectively recruited. Two groups were stratified, diabetic group and control group. Central corneal thickness (CCT), keratometry values (Kmean and Kmax), corneal volume (CV), anterior chamber depth (ACD), anterior chamber volume (ACV), Qvalue, frontal and back elevation, and the parameters of corneal variance indices, including minimum radius (Rmin) were measured using Pentacam Scheimpflug camera. Endothelial cell density (ECD) was also recorded. Findings were evaluated and compared between the 2 groups.Results: Two groups were found to have different Kmax (P = 0.03, one-tailed) and Rmin (P = 0.04, one-tailed) parameters. There was no statistical significant difference between the 2 groups in CCT, Kmean, CV, ACD, ACV, frontal/back elevation, Qvalue, ECD, and parameters of corneal variance indices.Conclusions: Diabetes mellitus affects keratometry and radius values of the human cornea based on the corneal measurements from Scheimpflug camera.

Convertiplane is explored in this article as an unmanned aerial vehicle incorporating hybrid power sources and hybrid propulsion systems. Based on the use of an electric generator in conjunction with a battery, fuel element and internal combustion engine as a source of energy in the non-manifold electrical engine convertiplanes, hybrid power sources and hybrid propulsion systems manufacturing specifications, as well as providing convertiplane with a long-term flight issues are considered hereby. In order to provide selection of the optimal design, hybrid energy source models from connection designs of different types of energy sources have been analyzed. Structural schemes of power systems with different configurations consisting of “sequential”, “parallel” and “mixed” connections of hybrid energy sources and hybrid propulsion systems have been analyzed and optimal connection schemes have been determined on their basis. It has been shown that when using four hybrid winged-motor group, the lifting system becomes complicated, the weight of the convertiplane is becoming relatively heavy. For an airplane weighing 15-20 kg, it is recommended to use four electric motors as a lifting engine, an internal combustion engine as a driving motor and an electric generator to charge the battery during the flight in order to ensure vertical flight, endurance or hovering at the height. A conceptual block diagram of a convertiplane type unmanned aerial vehicle is developed.

The conference material consists of designing a convertiplane-type unmanned aerial vehicle and optimization of its main parameters in the context of observation of strategic objects, the selection, manufacture or purchase of components for the designed convertiplane, as well as the determination of the very low probability that the aircraft will be detected by visual, acoustic and radar detection means. Also, the structural emplacement and layout of the elements that make up the aircraft have been studied, the purpose of each element selected during the design, the impact on the aerodynamic characteristics of the aircraft and its location were technically justified.

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Currently, due to the increasing accuracy required to determine the center of mass and gravity, the development of methods and technologies in this direction remains a high priority. In the research work, the characteristics of the available methods and tools for determining the flight load and centering, as well as the analysis of the research work on determining the center of mass of the aircraft, calculating the weight and centering cost were carried out. When designing and preparing aircraft, in order to increase the efficiency and safety of their flights, it is required to correctly determine their loading, centering and center of gravity. The methodology of using the "balance-mass" method, which is widely used in determining the center of gravity of aircraft, was developed in our research conducted for this purpose - in the example of a convertiplane-type UAV. It is known that it is possible to determine the coordinates of the center of gravity of gliders beforehand based on survey books. This data only corresponds to the state of the glider without load and not on the final delivery. The article also describes the essence and capabilities of the developed method for determining the center of gravity of the aircraft with higher accuracy. The results of theoretical and experimental studies on the creation of a system for determining the weight and center of gravity of the UAV in practice are shown. The proposed system construction model is presented.