Problem. The T-156B hinge frame of the loader, which is an upgraded frame of an agricultural tractor, during work operations creates loads for which it was not designed. Such loads lead to breakdowns and further shorten the life of the entire machine. The frame is the basic element around which the machine is built. The loader that had just been removed from the conveyor did not have built-in durability and reliability. While designing a road construction machine, an account of the features, nature, and conditions of its operation should be taken. Goal. Develop a hinge frame design technique that takes into account the loads experienced by the frame with a virtual simulation of real-world situations during the loader process. Methodology. The adopted approach is based on the use of a computer program Solidworks with three-dimensional modeling and a program Ansys motion for calculating the dynamics of multicomponent bodies taking into account the hinge and contact interaction. Results. In the work were considered three cases of technological operations of the loader. 1. Lifting a full bucket. 2. Collision with an obstacle that is difficult to overcome 3. Movement over an uneven surface with the raised loader arm. The results of the calculations provided forces and torques in the hinge of the half-frames, as well as the effort of the frame. Based on the results obtained, the endurance of the frame in the Ansys motion software package was calculated. Originality. The analysis of load-bearing systems with a virtual simulation of the machine’s actual behavior with the help of Ansys motion software allows to obtain more accurate results, significantly reducing the time for the design and cost of field testing. Practical value. This approach to the analysis of the carrier system behavior can be recommended for designing and determining the technological capabilities of wheeled, tracked, and special machines.

Problem. Special attention is paid to maintaining tower cranes in good working order and serviceable condition through their proper operation. Unfortunately, violation of the operating rules can lead to an emergency situation. In this case, both the crane operator and other workers on the construction site may be injured. And in some cases even to death. Therefore, the development of measures for safe operation is very important. It is also important to ensure sufficient strength of the load-bearing steel structures, which make up the bulk of the tower cranes, the breakdown of which leads to significant costs to restore the working condition of the tower. Goal. The goal of the work is to develop a method of interactive graphical modeling of three-dimensional models of metal structures with the use of a forced variation of their dimensions in the environment of computer-aided design – Autodesk Inventor package. Methodology. The solution of the set tasks implied the use of computer modeling methods with the use of modern 3-D modeling programs. Experimental studies were also carried out to determine loading modes. Results. A comprehensive methodology has been developed that uses the method of interactive graphical modeling of three-dimensional models of metal structures with a forced variation of their dimensions in the computer-aided design environment - Autodesk Inventor. It allows you to obtain rational parameters of the main elements of the tower crane – tower, boom, and others. This technique significantly increases the productivity and quality of the designer's work and reduces the time for research (tower cranes) and design documentation. Originality. The method of interactive graphic modeling of three-dimensional models of metal structures on the example of the tower crane with the use of a forced variation of their dimensions in the computer-aided design environment – Autodesk Inventor package is offered. Practical value. The use of the proposed methodology will significantly improve the efficiency of the design and operation of tower cranes.

Problem. The problem is an integral part of developing the concept of forming a standard range of transport and technological hydrophilic modular means for maintenance of airfields and aircraft. Goal. The goal is development of scientifically sound recommendations for determining the rational parameters of the hydraulic system with automation of control and energy saving during operation of modular vehicles for maintenance of airfields and aircraft, taking into account the potential of domestic engineering and critical imports of units and assemblies. Methodology. The methods include analysis of energy saving methods in  hydraulic fluid power of mobile machines according to manufacturers' catalogs and industrial examples taking into account the needs of modular vehicles for maintenance of airfields and aircraft, in particular, taking into account the creation of modern hydraulic devices and circuit solutions in hydraulic drives with throttle and machine control and automatic regulators of change of hydraulic  fluid power. Results. It is established that in hydraulic drives with throttle control and pumps with unregulated working volume, throttles on parallel flow and three-wire flow regulators or LS and LUDV modern systems are used; automatic pressure and flow regulators are used with pumps with adjustable displacement; in machine-controlled hydraulic drives through the use of pumps and hydraulic motors with adjustable displacement and hydraulic automation; by energy recovery during operation and bench tests of hydraulic drives; at the design stage of hydraulic drives, when the static analysis is performed in terms of efficiency and dynamic to reduce the loads on the starting modes of operation; and also at designing lay the effective circuit technical decisions promoting energy saving; directly in operation due to high-quality working fluids, heat exchange systems and filtration. Originality. The classification of methods of energy saving in volumetric hydraulic drives of mobile machines is made and examples of application of some means which are planned for introduction in transmissions and the technological equipment of cars for service of aerodromes and planes are resulted. Practical value.  The possibility of a rational selection of axial-piston domestic hydraulic machines for the development of hydraulic drives for airfields and aircraft is proven.

In this paper, for the first time, the effectiveness of network steganography methods has been investigated using channel coding of data when they are transmitted over communication channels with interferences, and the method of mathematical modeling evaluates the stability of network steganography methods to the detection. The network steganography methods concealing data in such protocols as HTTP, TCP and ICMP were considered. Using the ICMP «Secure» mode of the developed method, the greatest throughput was achieved. To study the noise resistance of the methods before transmission by the communication channel, the packets were encoded using the 2 Binary 1 Quandary linear coding algorithm, after which additive white Gaussian noise was added to the stego object. The paper substantiates the possibility of using network steganography methods to protect biometric data from unauthorized access in the case of using remote biometric authentication. Based on the research results, it was determined that the network steganography method based on hiding data in TCP is more efficient when working via communication channels with noise. It makes possible to recover a message with small distortions at a dispersion value of 0.4. But according to a set of criteria for resistance to noise and detection probability, the best is the «Fast» mode of the network steganography method based on hiding data in ICMP. Анотація-В роботі вперше досліджено ефективність методів мережної стеганографії за умови використання канального кодування даних при їх передачі каналом зв'язку з шумами та оцінено стійкість методів мережної стеганографії до виявлення. На основі результатів досліджень визначено, що метод мережної стеганографії з використанням протоколу TCP є більш ефективним за умови роботи каналами зв'язку з шумами, але за сукупністю критеріїв стійкість до шумів / прихованість найкращим є режим «Швидкий» методу мережної стеганографії з використанням протоколу ICMP.

The article is devoted to the study of the immunity of biometric templates to interference and fading during transmission over the LTE network. The widespread use of remote biometric authentication systems, primarily in remote mobile payment systems, determines the relevance of the chosen topic, and the development of mobile networks, and, first of all, the use of technologies that are more protected from attacks like LTE increases its practical focus. However, when authentication information is transmitted, even over a secure channel, it can be subject to interference and fading. That is why it is important to study their impact on the integrity of the biometric template that will be used to authenticate the user in the system. The paper analyzes the dependence of the quality of the authentication system on the parameters of the mobile communication channel (bit error rate, signal-to-noise ratio) and the parameters of the mobile device that transmits information (MIMO scheme, code rate, modulation scheme), which improves the quality of the remote biometric authentication systems by reasonably choosing the transmission parameters and taking into account the parameters of the communication channel.