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The paper is devoted to application of the methods of nondestructive testing and visual examination using UAV (drones) for evaluation of damage of the TV tower structure. A methodology is described, which includes application of aerial photography and photogrammetry method to construct a 3D model of the TV tower and localize the damage. 3DF Zephyr software was used to plot a 3D-model, which allowed sizing the defects and classifying them. Conducted examination provided the grounds for elaboration of the recommendations on operative repair and restoration of the TV tower to ensure its safe operation. The presented results confirm the high potential of the combination of the traditional nondestructive testing methods with remote diagnostics based on application of drones and photogrammerty for examination of large-sized structures. [ABSTRACT FROM AUTHOR]

In March–May 1982, a local expedition worked in the Arctic, in the east of Wrangel Island (WI) and Herald Island (HI), to carry out a survey of polar bear dens. The results of that expedition have not been published. The author has found a copy manuscript of the expedition diary in Kyiv and has highlighted the key results. For two months, five explorers had been surveying the area and found 139 dens and sighted 57 bears (+ad + juv). The average number of offspring (ANO) was 1.43 on WI and 1.86 on HI. The number of successful offspring on WI usually was one or two cubs, or even three on HI. Based on the available sample (n=44) it was shown that when taking into account the survey data of cub traces in calculations of ANO (on WI), the obtained results do not differ notable. The time that lasted from the date of the opening of the den to the date of the final leave of the den by females (with or without the young) was 4 to 14 days, but most often 6 days. The highest frequency of den opening was noted on 27–28 March. Four cases of death of cubs, including a newborn, were recorded. The fate of 43 dens was monitored and measurements of 11 dens were taken. Two unusual dens were found: one with a very complex corridor and another one with a 4.5 m long vertical tunnel. Simplified 3D models of dens were given in the article for the first time proving that linear measurements practiced by researchers give a primitive picture of the den structure. After leaving the maternity den, the female can build temporary, simple shelter for herself and the young. During 1964–2020, dens were found on these islands only on the ground, and in 1980 the author found several dens on the sea, among ridges of pressured ice. The article is amended by the author’s estimations regarding the place of the polar bear in ecological pyramid of those islands. Recommendations are given for the improvement of polar bear survey techniques. The publication of a Ukrainian language article on the biology of U. maritimus is rare for the school of Ukrainian mammalogists and is of clear enlightening importance for scientists, lecturers, students, Wikipedia editors, and others, as well as a contribution of the author to the Ukrainian body of literature on the animal world of the Arctic.

The increasing number of hip replacement surgeries in the worldwide practice causes the progressive increase in revision cases. The treatment of patients with instability of the hip implants requires the individual approach, taking into account the size of the defect, the loss of bone mass and the structural state of the bone in each case. Objective. To show the technical opportunities of the revision cementless implants in combination with 3D-modeling for the treatment of acetabulum massive defects. Methods. It was shown the clinical case of hip replacement surgery of the patient with the aseptic instability of endoprosthesis components. A 3D-model of the pelvis and femur was created on the basis of the CT scan in order to make an analysis of bone tissue defects and to select the exact size of implant components for revision surgery. Results. It was suggested a standardized methodology of the preoperative examination to make the hightech operation easier and maximally effective. It is necessary not only to take into account the results of the Xray analysis, but also to pay attention to all changes in the damaged segments. It was shown that the real plastic model make the work of the surgeon easier during all steps of the treatment. The opportunity to use the standard revision components for the restoration of the complex geometrically shaped bone was demonstrated with the good nearest clinical and radiological and functional results. Conclusions. The success of the revision arthroplasty depends on the carefully preoperative planning, the maximum approximation of the parameters of the artificial joint to the anatomical parameters of the patient and biomechanics of the hip join. No less important is the individual recovery program during the postoperative period. [ABSTRACT FROM AUTHOR]

The universal algorithm, independent of geometric parameters of detail and required cutter type, becomes relevant within using modern computing means. Following this argument the universal mathematical model, which generalizes formerly known approaches in the designing of different cutter types is offered. The initial data for calculation are the number of points on the detail surface, the values of rake and clearance angles, parameters of detail in each point of the surface and the axial distances of these points from the flat end chosen as the datum. The cutter type has no influence on the calculation algorithm. 3-D modeling is the easiest way to do graphic profiling. Profiling process is based on determining the initial tool surface and characteristics. The comparison of the results of analytical and graphic profiling of form cutter shows the full match in all points, which confirms the adequacy of the mathematical model and the graphic profiling algorithm

A three-dimensional solid model of a special-purpose mill-drill-bore machine VM1F4 with CNC in CAD KOMPAS-3D was developed. A study of the design performance by strength and stiffness criteria using the finite element method within an APM FEM module, integrated into the KOMPAS-3D system was carried out. A three-dimensional model of the turntable of the considered machine using the original embodiment of sliding supports and anti-backlash worm gear was presented. The need for such works is caused by, on the one hand, the requirements of an integrated approach to creating competitive machine tools, including the construction of a three-dimensional representation of complex design and optimization of the product according to the metal intensity and stiffness criteria. On the other hand, the implementation of an integrated approach is reasonable to carry out using low-cost CAD, which corresponds to the financial capabilities of small and medium-sized design divisions. Version of an integrated CAD KOMPAS-3D with integrated SAE - ARM FEM module is the most appropriate. As a result of investigations, the rational structure and shape of the machine complex that includes machine spindle positioning device and turntable device with a vertical and a horizontal axis for implementing complex shaping movements was determined. A new approach to improving the accuracy of dividing movements of the turntable due to using a new method of clearance compensation in the worm gear was proposed. The obtained results allow to outline the ways to improve the design, by determining dangerous sections and implementing a version of the spindle, approximated to full-strength part. In conditions of the long operation, the option of maintaining the accuracy characteristics of manufactured products by reducing the errors of dividing movements of the turntable of the machine with the workpiece mounted thereon was proposed. [ABSTRACT FROM AUTHOR]

In the article undertake the attempt to formulate the definition of 3D-model and process of 3D-modeling in industrial design, cons hit definitive aspects of this conception from the position of industrial designer and todays production process.