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The pulsation bottles are mounted at the inlet and outlet of / from the reciprocating compressor cylinders to even out the gas parameters (pressure and temperature). They ensure stable working conditions in the compressor cylinders and eliminate / reduce vibrations. The sizing of the pulsation bottle is done based on the geometric parameters of the compressor, the volume efficiency and working pressure. The use of a dynamic model made in the LMS Amesim program allows the study of a compressor with a set of pulsation bottles at the modification of: the pressure and temperature at the inlet / outlet of the compressor, the speed of the compressor the volume of the dead space and blocking or removing of the valves. The model includes the compressor cylinder with the corresponding dead spaces, the compressor valves, the suction and discharge pipelines and crank connecting rod mechanism. The simulation takes into account of the: gas composition, temperature and pressure in the system. The variation of the pressure in the bottles can be checked under these conditions. The values of the disturbing forces for a range of working and adjustment parameters can be obtained, values that can be used in a dynamic analysis according to API 618.

In parallel with global technologies and transformations, Georgia was intensively reviving and developing all types of tourism, the COVID-19 pandemic slowed the pace of rapid growth in the quantitative parameters of tourism, and then shifted tourism to a phase of economic uncertainty, leaving all types of tourism paralyzed. The main goal of the research was to identify the challenges facing cruise tourism and to develop recommendations for its development.The article discusses the importance of developing cruise tourism for the revival of tourism in Georgia. The potential of cruise tourism is characterized. According to the trends of the world, based on the annual report of the International Association of Cruise Lines for 2020, the statistics of cruises around the world are analyzed.We believe that educational projects should be started for tourism business owners, staff should be trained to give accurate recommendations regarding maritime cruises and COVID regulations, travel companies should be given the opportunity to take low-interest loans if necessary; State support for the promotion and development of tourism, including cruise tourism, is important.

Knowledge of the technical state and construction of the hydraulic and pneumatic control system of Multimedia Hybrid Mobile Stage HMSM allows you to identify hazards and make a risk assessment. The aspects of the algorithmic process of diagnosing pneumatic and hydraulic control systems presented in the work form the basis for the development and implementation of safe solutions in the process of operation. This article describes the methodology for diagnosing HMSM machine hydraulics and industrial pneumatics systems, detailing the factors determining the correctness of maintaining functional fitness. The considerations developed illustrate the complexity of the diagnostic testing design process for condition assessment.

In Romania, as in many other countries of the world, there are areas, more or less extensive, which are naturally prone to landslides. Such an area, with great extension, is represented by the Getic Subcarpathians. In general, this predisposition of the mentioned area to landslides is favored by its geology and hydrogeology, its lithological structure, its morphology, the rainfall regime and to a lesser extent the tectonics of the region. Based on these considerations, in this paper, we have conducted a comparative study aimed at highlighting in a more concrete manner the causes that led to the onset of land instability phenomena recorded in the past 17 years in this area, also taking into account the human activities. For this purpose, we delimited three study areas, corresponding to the counties of Gorj (an area with shutdown mining activities), Vâlcea (area with lignite open-pits in operation) and Argeş (where human actions that can trigger landslides are related to infrastructure constructions, especially by excavation, other constructions, but also deforestation). This approach allows us to draw conclusions about the extent to which human activities amplify the frequency and intensity of land instability phenomena, and which of these activities has the most unfavorable influence.

This paper is devoted to the modal analysis and buckling of a stiffened plate with simple supported conditions within the framework of shell theory. The main objective of the finite element analysis is to investigate the natural frequencies of this stiffened structure subjected to uniaxial compression on two opposite edges of the plate. In this study, the numerical analysis is performed for such a design of the stiffed plate which has already been optimized for uniaxial compression, some design variables and the cost of welding, and the objective function to be minimized is defined as the material cost. The various Young’s modulus of the base plate and the stiffeners are given thus assuming that the plate parts (the base plate and ribs) were made of different steel materials.

The article gives the description of the developed technology of increasing wear resistance of working elements of national and foreign constructional and road machines by composite coatings, obtained on working elements cutting surfaces applying Carbo Vibro Arc Hardening method (CVAH). The technology includes the following basic operations: cleaning and fault detection of the working element, removal of the worn cutting element, compensating element production, its sharpening and welding, preparation of metal and ceramic paste for Carbo Vibro Arc Hardening method (CVAH) and its application, Carbo Vibro Arc Hardening method (CVAH) of the harden cutting surface of the working element. When hardening new working elements technological process operations connected with production and welding the compensating element is not performed. According to the carried out results the rational composition and component concentration of the paste that provides significant increase of working elements wear resistance.

The characterization of the structural arrangement of an unsaturated soil is important for the understanding of its behavior. For expansive soils, obtaining this information and combining it with an understanding of their intrinsic and extrinsic properties, makes it possible to predict their performance. The experimental procedure for this study was developed using the expansive soil of the Maria Farinha formation in the city of Paulista, in Pernambuco, Brazil. Physical and chemical characterization tests, edometric tests with wetting, and structural analysis through X-Ray computed tomography were performed for both undisturbed and compacted samples, before and after wetting and swelling. The compaction process was performed without any prior air drying and without loosening, beginning with the field moisture level. Based on its liquid limit and plasticity index, the soil can be classified as CH according to the USCS, moderately acidic, with a swelling potential ranging from high to very high, depending on the initial suction of the sample. The analysis of the soil macro-structure revealed a smaller number of voids in the compacted samples. In addition, it was found that the wetting process caused a reduction of the soil macro pores, in both cases.

In this study, magnetorheological fluid (MRF) was prepared with several kinds of hydrophobic fumed silica in order to improve MRF stability while maintaining desirable fluidity. We conducted steady flow measurements and oil separation tests under gravity and centrifugal conditions. The linkage of fumed silica particles was also observed morphologically by transmission electron microscopy. We found that the MRF sedimentation stability correlated with viscosity in the lower shear rate range. The oil separation ratio improved with the addition of the fumed silicas examined in this study. The surface characteristics of the silica particles affected the stabilization ability. The addition of hydrophobic fumed silica can desirably increase MRF magnetic properties.

The article considers problems of a transport complex of mining and processing plants. Requirements for quarry transport are presented. The production process and technological operations of the transportation process are considered. The ways of solving the problems of the transportation process are determined. It is established that when creating a rational system for transporting iron ore raw materials, it is possible to reduce material costs and losses during transportation.

Technological innovation and achievement transformation are an important starting point for constructing an industrial innovation ecosystem and coping with hindered external demand. This article starts with the ecological chain of technological achievement transformation, constructs a transaction cost and benefit model of three transformation modes of direct transformation, intermediary participation, and co-construction cooperation, and systematically analyses its transaction costs, benefits, application and the value space of the transaction subject of each mode. With the participation of intermediaries and investors, the "government, industry, university, research, and financial agency" achievement transformation service platform not only reduces transaction costs but also greatly increases returns. Using the advantages of big data and blockchain can obtain more added value than other models, bringing more opportunities for both supply and demand.

The first of the general objectives of the National Strategy in the field of health and safety at work for the period 2018 - 2020 in Romania was “a better implementation of the choice of occupational safety and health legislation, especially in micro-enterprises and SMEs”.In this context, this paper presents the main vulnerabilities of management in SMEs, where the occupational safety and health component has a formal role being strongly influenced by economic factors. The first part presents a statistical situation of the verification campaigns, carried out in the last 3 years by Labor Inspection, on how SMEs have implemented health and safety legislation in their activities, subsequently, an analysis is made of the economic factors that have limited the development of health and safety management. Finally, a cost-benefit analysis is presented on the economic consequences that occur in the event of an accident and / or illness that demonstrates the theory that economic factors influence the management of health and safety and health specific to SMEs both before and after an event occurs.

The features of carrying out an autotechnical expertise (ATE) are considered in case the vehicles (V) participating in the road transport accident (RTA) don’t leave skid imprints. The examples of momentum and energy conservation law application are given at developing the road accident mathematical model. Special attention is paid to the determination methods of vehicle (V) velocity, travel directions in various RTA diagrams and archeology of deformation. For this purpose it is offered to draw a momentum vector diagram. It is reasonable that for the calculation of V deformation at RTA it is necessary to determine step by step the strain-stress state in a contact area on the basis of the theories of elasticity, plasticity, solid friction and finite-element methods. The technique of constructing an RTA mathematical model is developed. It is recommended to use at ATE of RTAs at the runs-over into the fixed obstacle (a stationary V) and collisions.

A graph-analytical optimization model of the formation of the regional transport complex management system (RTC) is presented. The model allows analyzing and implementing priority selection in the formation of effective control schemes for the RTK management. It allows taking into account socio-economic characteristics of a specific region when carrying out comparative analysis of the existing management models. The model is based on the ideas of cognitive approach for solving semi- structured problems.

At the underground mining works performed in coal, rock and mixed coal & rocks, the process applied almost exclusively is by drilling & blasting. Given that the mines in the Jiu Valley are classified as methane mines, this involves the use of explosives and means of initiation that are safe from methane gas and coal dust. To date, permissible powdered explosives have been widely used. The drilling & blasting patterns were established according to the physical - mechanical and geological characteristics of the rocks in the massif, the type and section of the mining works as well as the restrictions imposed by the methane regime of the mines. In recent years, the widespread use of emulsion explosives has led to the development of permissible types of emulsion explosives. In order to use the permissible emulsion in the coal mines in the Jiu Valley, it was necessary to test in the INSEMEX landfill the safety and functioning parameters as well as to perform underground blasts, in the specific conditions of the methane coal mines. The paper describes the underground experimental blasting works performed, as well as technical and safety recommendations for the use of this type of explosive - permissible emulsion.

In this paper, in view of the characteristic that UUV radiation noise is low and easily interfered by strong noise, the complementary Ensemble Empirical Mode Decomposition (CEEMD) combined with symmetric correlation processing is proposed, which can improve the extraction performance of UUV’s propeller features. First, the CEEMD decomposition combined with symmetric correlation processing was used to reduce the radiated noise of the target, then the signals after the noise reduction were demodulated and computed to obtain the DEMON spectrum, and finally features such as the rotational speed of the UUV’s propeller were extracted from the DEMON spectrum. The Sea trials signal processing results prove that the method has better noise suppression performance under low SNR conditions, and can clearly and comprehensively extract the DEMON information of the radiated noise, and then accurately extract the propeller features of the UUV. Compared to conventional demodulation techniques, this technique has a greater ability to suppress noise and does not require manual selection of the modulated frequency band.

The paper uses pollutant emissions calculation methods in accordance with GOST (All-Union State Standard) in combination with the method of mathematical statistics, which makes it possible to determine the amount of emissions from automobile transport, which is in line at a red traffic light in the area of a controlled intersection. The methods allow calculating such environmental indicators as the mass of pollutant emissions, the concentration of pollutants and the Air Pollution Index. The authenticity of this technique is confirmed by testing the hypothesis on the Pearson Law of distribution of pollutants. Based on the combined methodology, the software has been developed with the purpose to monitor atmospheric air pollution. This approach will make it possible to qualitatively assess the level of atmospheric air pollution and take timely measures in the event of dangerous environmental conditions.

The existing self-sovereign identity management schemes have some problems, such as weak availability and security risks. To solve these problems, we proposed a cross-domain self-sovereign identity management scheme using smart contracts. This scheme takes into account the entire lifecycle of identity, especially including the cross-domain use and recovery. To preserve the privacy data of users on the blockchain, we proposed a data storage method of anchoring on blockchain. Finally, we implemented this scheme using the Solidity programming language for smart contract. This scheme has been experimentally verified to be capable of maintaining the expenditure of resources under control and having good usability. Compared with other self-sovereign identity management schemes, this scheme has better performance in terms of controllability, security and portability.

Nonprofit organizations implementing their strategies through multi-project environments are perennially confronted with the difficulties embedded into their institutional design. Assessing the social results is intrinsically dependent on the missional depiction of social change and it is to be performed in settings of project networks influenced by multiple stakeholder interests. In order to balance the project efficiency, in terms of the triple constraint of scope-time-budget, and the need for stakeholder satisfaction, when it comes to project intake decisions a procedural decision making approach is required. The aim of this paper consist in proposing a decision making process and the adjacent procedures set for project intake decisions guided by various criteria. This process takes into account: mapping the stakeholder’s importance and influence on strategy casting, assessing the social outcome of projects and project efficiency requirements.

Based on the finite element method, this paper first discusses the sound absorption characteristics of acoustic materials with a cavity structure backed by air, and then takes the internal cavity of the acoustic material and the acoustic material as the research object, considering the sound waves of different frequencies and different incident angles. The maximum sound absorption coefficient is used as the objective function to optimize the design of the cavity acoustic material. The calculation results show that the sound absorption performance of the optimized acoustic material has been significantly improved.

Tests of vehicles of category M1 were carried out when using the BRAKE TESTER descener model LWS models - 2 / MC on: dry asphalt concrete coating T = (0 ± 0.5) ͦ C; dry asphalt concrete coating T = (+17 ± 0.5) ͦ C; Rocherated snow coating T = (-15 ± 0.5) ͦ C; The calculation method is considered, the results obtained are analyzed.

To reduce the delay of content acquisition, this paper proposes a game-based cache allocation strategy in the Information-Centric Network (ICN) slice. The cache resource allocation of different mobile virtual network operators (MVNOs) is modeled as a non-cooperative game model. The Newton iterative method is used to solve this problem, and the cache space allocated by the base station for each MVNO is obtained. Finally, the Nash equilibrium solution is obtained. Simulation results show that the proposed algorithm can reduce the delay.

The solid particles or liquid droplets entrained by multi-phase flow in process plants can cause erosion resulting in pipe wall thinning. Hence, it is essential to evaluate erosion rate for determining design margin and taking counter-measures. Many models have been proposed for prediction of erosion induced by particles and droplets, but there is significant difference in their prediction accuracy. The present study aims at verifying prediction accuracy of some major erosion models using the published experimental data, for engineering applications. CFD benchmark simulations were conducted for different flow velocities and piping geometries to investigate prediction accuracy of particle-induced erosion rates for five major erosion models, using the experimental data in literature. CFD results show that the erosion rates predicted by Grant and Tabakoff model are closest to the experimental results with acceptable prediction accuracy for engineering applications. At the same time, CFD benchmark simulations were also carried out to verify the prediction accuracy of droplet induced erosion rates for three erosion models, using the published experimental data. CFD results show that the erosion rates predicted by Haugen model for all the water impingement velocities are closest to the experimental results with acceptable prediction accuracy for engineering applications.

The author's team analyzed a bicycle as a two-wheeled vehicle. (TWV) The purpose of the study was to estimate the parameters affecting the reaction time of the cyclist. Depending on the type of brake system, the mass of the two-wheeled vehicle and the cyclist, the speed, and the bicycle designs graphs were built, and their analysis was carried out. Based on the test results, factors affecting the cyclist reaction time in case of danger were disclosed.

Swelling and shrinking properties refers to significant positive or negative variations of volumes due to absorbtion or dessication of water in fine soils under natural or anthropic regime of moisture. These physical phenomena are worldwide spread and had important engineering consequences with associates cost of damages of several billion annually in all climate areas. In spite of the fact that these geotechnical properties are studied for more than eight decades, the particularities of these peculiar relations between water, mineral composition and geomechanical behavior are still unrevealed entirely. In Romania, swell/shrink soils are reported in all regions at different depths, but rarely related to geotechnical engineering accidents such as slope slides or road failures. This work presents some obvious relations between the hydrogeological structure, the presence of “large swell/shrink soils”, their mineralogical composition and geomechanical properties and the ubiquitous landslides on Peri Carpathians Hills. Large infrastructure projects offer the opportunities to put into evidence the swelling properties of Upper Pliocene-Lower Pleistocene deposits, which supports the Holocene alluvial deposits of Argeş River. Analyzed samples allow us to define some basic correlations between plasticity index, colloidal fraction, dry density, swelling pressures or free swelling and mineralogical composition.

This article represents the analysis results of normative legal regulation in the transport services field for people with limited mobility (LMP) and assessment methods of transport services quality provided by public transport for the same social group. The main conclusions of the significance examination of quality parameters are given below. The essential problems of transport accessibility provision were defined by materials of sociological polls.

Crankshaft is one of the crucial parts for the internal combustion engine which required effective and precise working. In this study, the aim of the study is to identify the stress state in the crankshaft and to explain the failure in automotive crankshaft and fatigue life of crankshaft by using finite element analysis. The 3D solid modelling of the crankshaft model was designed and developed using SolidWorks. A static structural and dynamic analysis on an L-twin cylinder crankshaft were used to determine the maximum equivalent stress and total deformation at critical locations of the crankshaft. The model was tested under dynamic loading conditions to determine fatigue life, safety factor, equivalent alternating stress and damage using the fatigue tool. The results obtained from this study indicated that the crankshaft has obvious fatigue crack which was belongs to fatigue fracture. The fatigue fracture developed was only attributed to the propagating and initiate cracks on the edges of the lubrication hole under cyclic bending and torsion. Overall, the crankshaft is safe for both static and fatigue loadings. In dynamic analysis, the critical frequency obtained in the frequency response curve should be avoided which it may cause failure of the crankshaft.

The article deals with the problems of finding the most rational method of developing the strength qualities of students of civil aviation universities, and in particular the direction of training “Air Navigation” (ATC), by optimal distribution of the time of power loads for the formation of professional training of future specialists of airfield services. In the structure of such training, a special place is occupied by power qualities, which are most important for specialists of airfield services, who ensure the safety of air transport. Strength training not only increases the body’s resistance to the effects of adverse environmental factors and strengthens the immune system, but also optimizes the functional state of the body. However, the issues of the development of strength abilities with the use of time indicators in the distribution of specialized loads are currently insufficiently studied and do not have a scientific basis in the general system of physical training of students of educational institutions of civil aviation. In the study performed on students, the search for optimal methods for the development of strength qualities was conducted by changing the time indicators in the distribution of specialized loads. Students performed strength and speed-strength exercises with high intensity and subjective power of effort, as well as cyclic exercises that require endurance when they are performed repeatedly. These exercises were considered by us as complex means of forming motor qualities. The studied main indicators of strength qualities allowed us to determine the main vector of building classes for future specialists in the field of training “Air Navigation” (ATC) and the means of controlling the functional activity of those involved. The experimentally based methodology for the development of power qualities is recommended for use in the educational process of educational institutions of civil aviation.

This paper aims to highlight the efficiency of using the method of observing student behavior in the educational environment. Observation is one of the most widely used research methods in the social sciences. The characteristics aimed at constructing the instrument were: accuracy, focus, duration of observation, awareness of the presence of the observer, the level of information of the subject. In order to observe the student’s behavior in the school environment, the observation grid with standardized answers was designed on the Likert scale (scale from 1 to 10), following the degree of expression of the described behavioral manifestations. The observation grid of the student’s behavior in the school environment aims at supervising 4 dimensions (each with 5 items: observable behaviors): interest in school activities, organization of activity / punctuality in the school environment, resistance to intellectual effort, socio-affective relationships. Following the application of the research tool, depending on the scores obtained, it is recommended the targeted psycho-pedagogical intervention at the level of the deficient dimension / behaviors, as well as the monitoring of the results through the periodic application.

The construction of index system is the basis of equipment system contribution rate evaluation, and is also one of the main contents of equipment test and appraisal. This paper discusses the concept of systems contribution rate, introduces the evaluation process of system contribution rate of information system equipment, and gives the construction principles and ideas of information system equipment system contribution rate evaluation index system. Then, referring to the theory of operational loop, the evaluation index system of system contribution rate is given from the perspectives of system capability and system effectiveness. The evaluation index of this paper can provide decision support for the development of equipment planning system.

INSEMEX-OEC is a Conformity Assessment Body for certification activities in accordance with ATEX Directive 2014/34/EU, being accredited by RENAR and notified to Brussels (NB1809). INSEMEXGLI (Group of Testing Laboratories) is the main provider of laboratory testing services for the product certification body INSEMEX-OEC. The test laboratories meet the requirements of the standard SR EN ISO / IEC 17025. This standard requires laboratories to have a procedure in place to monitor the validity of the test results. This monitoring must be planned and, if possible, should include participation in inter-laboratory comparisons or proficiency testing programs. This paper presents some specific issues highlighted during the successful participation of INSEMEX-GLI in a round of inter-laboratory comparisons organized by the Physikalisch-Technische Bundesanstalt from Germany to determine International Protection Code (IP Code) for equipment enclosures.

This paper is made within the European project GoldenEye Nr. 869398 Type Horizon 2020 and aims at geometrization in 3D format of the Rosia Poieni deposit. This geometrization will be based on the information on the contents of the deposit, the economic analysis, and the calculations of the stability of the open pit and the adjacent industrial waste dumps. The analysis of data from the literature on content is in a very wide and insufficiently relevant range. The study will be based on the latest scanning technologies, AI, numerical simulations (FLAC 2D), which will form the basis of an economic analysis and forecast of metal prices in the future in order to identify exploitable limits both horizontally and vertically. Depending on the extension of the exploitation area and the definition of the deep exploitation limit by up-to-date exploitation, stability calculations will be performed, which will finally allow the geometry and safety of the deposit. Also, this geometrization will allow the decision-making of exploitation, extension, optimization by the management team and the administrative council of CUPRUMIN ABRUD S.A.

This article examines the problem of distance educational activities at higher educational institutions against the backdrop of pandemic. The article compares the work of foreign HEIs and the results of their activities. Particular attention is paid to distance education at Russian HEIs, including the Moscow State Technical University of Civil Aviation. The characteristic features of business processes of distance educational activities at the university using applied programs are determined and described. This problem has been little studied and requires further research.

The article is devoted to the optimization design of the stick of a hydraulic excavator at the most frequent and greatest value loads. The uncertain loads acting on the working equipment of the excavator were obtained by the Monte Carlo method based on 3D analytical soil-tool interaction models. The results show that the adopted methodology can be used to optimize the design of elements of the excavator working equipment, since the design of stick was obtained with less weight and lower stress values than the original design.

The article deals with the problem of transport management in all types of communication in the context of digitalization. Possible schemes of interaction between the subjects of the transport services market and various modes of transport in foreign trade transportations in mixed messages are presented. It is recommended that when choosing a route for transport and freight flows, take into account all types of interaction and coordination of activities of various types of transport, as well as subjects of transport and other markets.

Directions of the modern approach to the organization and safety of traffic in the conditions of the emerging tendency to creation of agglomerations in the Russian Federation are defined. The complex of innovative concepts in the country related to the effective development of these agglomerations is considered. The functions of the Center providing the unifying beginning of the concepts under consideration are defined.

Analyzed the use of the term «irregularity changes of technical condition of element’s vehicle» to certain stages of the operational cycle. Specific examples and quantitative assessment of irregularity changes the structural parameters for the elements, working independently, and interacting in the units or systems of the vehicle.

The article is devoted to the issue of improving the autonomous vehicles safety. The anti-lock braking system was chosen as the object of the study, since it is one of the components of the vehicle active safety during emergency braking. Its functioning varies depending on parameters such as vehicle type, transmission type, external and internal steering wheel angles. It is necessary to parameterize correctly the electronic control unit of the anti-lock braking system depending on the specific values of these parameters. For this, a software module was developed that reads the values of the vehicle parameters from a file and sends their array to the electronic control unit. Then we can check the result: how the block responded to the sent request -positively or negatively. All this will speed up the parameterization process, increase its accuracy, preventing the occurrence of operator errors during its implementation.

The article considers the problem of the analytical determination of the fuel economy performance of earth-moving machines by the example of the road grader. The values of the road grader fuel consumption when performing the technological operations have been obtained and analyzed. The fuel balance of the EMM in the traction mode is presented. The fuel balance of the motor grader when digging soil has been defined and analyzed.

Based on the experience accumulated over time on the evaluation of equipment and installations in environments with potentially explosive atmospheres, this paper is intended to be an element of synthesis on issues related to the “in situ” assessment and solutions of solvency the deficiencies found. The assessment of these installations is very important in order to verify the implementation of measures that lead to minimizing the risk of ignition of explosive atmospheres. Evaluation of these installations is made through an on-site visit and on the basis of the technical documentation developed by the care of the user. In first part of the paper were presented the legal aspects regarding the placing on the market and the use of equipment designed for potentially explosive atmospheres. The paper is continuing with the presenting the technical aspects regarding the evaluation of equipment and installations operating in potentially explosive atmospheres followed by requirements for electrical equipment. The main conclusion, of the paper is that the explosion protection of the equipment intended for use in potentially explosive atmospheres may be invalidated by the incorrect selection of the equipment, incorrect installation of the product, inadequate: performance of inspection operations, maintenance or repairing of equipment.

BP neural network is optimized by improved drosophila algorithm, and a prediction model for air quality in Nanchang is established based on the air quality data and meteorological data of Nanchang city in recent three years. The experimental results show that the improved algorithm has improved performance compared with the BP algorithm, and has improved accuracy 4%, with a small difference in time consumption. The performance of the indirect prediction method is slightly better than that of the direct prediction method

For now, many hospitals that require nurses to move patients by hand from stretchers to a hospital bed, so a design of stretcher with auxiliary functions of lateral positioning and transferring for immobilized patients, which is a mechanical mechanism consisted of rigid rods, joints and sliders, was designed to help the nurses to move patients between beds and reduce their workload. Driven by motors, the rigid rods can be rotated, stretched or shortened so that the entire stretcher bed board can archive to a proper posture and position. In this paper, the following objectives will be achieved: (i) Create a schematic of the mechanism and describe the principles and functions (ii) the calculation of inverse kinematics, forward kinematics, dynamics (including energy), and PD control in the mechanism (iii) The motion process of simulating the mechanism using MATLAB (iv) Using MATLAB to create the plots of angle, torque, and position state (v) Using SolidWorks to construct the prototype and to implement the motion simulation of the mechanism (vi) Describe the practical application and future Extensions of this mechanism.

The high degree of the trend in the development of the car park leads to significant problems: an increase in road accidents; reduced bandwidth, especially during peak hours; overrun and loss of time by road users; overconsumption of fuel and, as a result, deterioration of the environmental situation. One of the ways to solve the problem of traffic management is the use of intelligent transport systems (ITS). Examples of the use of ITS in various countries are given, improvements in the use of systems are considered. The system “Auto-Intellect” used on the territory of the Russian Federation is considered. On the example of the city of Belgorod, a method is proposed for using ITS by prohibiting vehicles from entering the city, taking into account certain state license plates.

The article is devoted to the interaction between the transportation sector and the environment in terms of global emission of greenhouse gas CO2 during combustion of various types of motor fuels. We offer a closed-tech recycling CO2 cycle by natural environment without using non-renewable oil fuels. Offered rate principles of green, characterized a complex level of vehicle impact on human environment.

The features of the control systems of temperature of the traction frequency converters consisted of rectifier, capacitor and voltage source inverter for traction rolling stock are discussed. The induction motor is considered as a load for traction frequency converter. The dependence of the number of thermal cycles from semiconductor junction temperature fluctuations before the failure of the semiconductor device are shown. The topology and operation principle of automatic temperature control system of voltage source inverter semiconductor devices of traction frequency converter are developed and described. The system is based on air forced cooling with the use of fan or blower as an executive regulation device. The main feature of the proposed system is the additional reference of switching frequency that allows to reduce the semiconductor temperature fluctuations. The elements of switching frequency control loop are chosen and evaluated, the recommendations on practical implementations are given. Simulation of automatic temperature control system in Matlab with both references of semiconductor junction temperature and its fluctuation was carried out with all essential nonlinearities of induction motors and semiconductor devices taken into account. Results of simulation are included and discussed.

A new developed scheme of public transport of the Belgorod agglomeration was introduced into the GIS system. This system allows to create a complete graph of roads with directions of public transport, as well as various information necessary to compile a full database. The data of dispatching points of public transport for obtaining velocity values on the edges of the graph of the roads of the city roads was surveyed.

The article presents an analytical review of information technologies in transport, identifies key areas, perspective development prospects.

Effect of grinding factor and scaling up were carried out by grinding using horizontal dry bead mill. For the experiments, 2 sizes of horizontal dry bead mills with different capacities, lab and manufacturing scale, were used to study scaling up and down. The grinding experiments were performed by changing each typical grinding factor for bead mills, including the agitator peripheral speed, bead packing density, bead diameter, and material feeding speed. This set of experiments was conducted for 3 kinds of materials, silica sand of natural inorganic materials, alumina of synthetic inorganic materials, and activated carbon of organic materials. As a result, common for all materials, similar rules were found between the particle size and specific energy, the amount of mechanical energy per unit amount of material. In addition, these rules were applicable for the different-size mills, indicating that the scale can be controlled by the rules and specific energy. Also, it is revealed that when using a single type of material, changing the bead diameter changes the energy efficiency, indicating that using small-diameter bead was effective for efficient grinding.

The system of technical operation (TO) of on-board equipment or avionics of aircraft (AC) as an object of research is a set of objects and means of technical operation, maintenance and repair programs, as well as personnel performing procedures and organizing the processes of TO. The quality of the TO system is manifested in the TO process - a set of processes of intended use, operational control, maintenance, restoration and repair. The TO process, as a process of changing the TO states, can be considered as a controlled random process, determined on the set of operation states by probabilistic characteristics. The quality of the TO system is characterized by a set of properties that determine its ability to satisfy with the maximum economic efficiency the needs of the TO system of the aircraft, while ensuring the required levels of reliability and readiness of the avionics for operation. That is, the TO system has all the features inherent in complex technical systems - a hierarchical ramified structure, subordination of goals and restrictions, wide interrelationships in the process of functioning. The main research apparatus in solving problems of optimization of processes and synthesis of TO systems is the apparatus of the theory of mathematical modeling of complex technical systems, based on a system approach, the integration of analytical and simulation modeling. The article solves the problem of determining the values of the parameters of the TO system such that the costs of the system during the TO process reach a minimum when all the required tasks are completed and all restrictions on the system’s own parameters and indicators of its technical efficiency are met.

Evaluation of the rolling resistance of car tires is now often performed on drum stands like car tests. This necessitates the study of the mechanics of interaction between the wheel and the drum in order to determine its force and kinematic characteristics, including the values and points of application of tangential and normal forces in contact with the drum. These problems can be solved taking into account that the mechanics of elastic wheel rolling on a drum is the same as when rolling on a flat rigid support surface. In this paper, from consideration of the mechanics of interaction between an elastic wheel and a drum, using the equations of power balance and force equilibrium of the wheel, the equations for determining the point of normal reaction in contact and its arm relative to the wheel axis during its rolling along one and two drums have been derived.. These dependencies have a simple form and can be applied when considering the rolling of both a single wheel and the car as a whole on a drum stand.

Industrial agglomeration is the most prominent performance in current economic activities. In this study, the output value of construction engineering is taken as the core index. The relevant data of 31 provinces and cities in China from 2008 to 2019 are selected. The spatial agglomeration level and spatial and temporal evolution characteristics of Chinese construction industry in 10 years are studied using the Gini coefficient and the strongest gravity model. Results show that the spatial agglomeration level of China’s construction industry has been increasing annually, and the industry has experienced the development process of “disequilibrium to gradual equilibrium.” (1) The distribution of construction industry in 31 provinces and cities of China is characterized by spatial imbalance. (2) The agglomeration areas of high–high construction industrial elements are mainly concentrated in Beijing–Tianjin–Hebei and Yangtze River Delta urban agglomeration. Low–low industrial element agglomeration areas are concentrated in the urban agglomeration of southwest China. (3) The center of gravity of the spatial agglomeration of the elements of China’s construction industry is moving from the east to the central and western regions and gradually tends to be balanced.