The Issue of Operating Security Systems in Terms of the Impact of Electromagnetic Interference Generated Unintentionally

This article discusses issues regarding electromagnetic interference generated unintentionally by transport telematics systems and electronic security systems (ESS) located within a railway area. These systems should operate correctly, since they ensure the safety of both vehicles and passengers. The electronic devices they use are exposed to electromagnetic interference that may lead to incorrect ESS functioning. In order to determine the impact of electromagnetic interference on ESS, the authors measured unintentional low-frequency electromagnetic field generated by MV—15 and 30 kV—power lines. This enabled determining the areas with maximum values of electromagnetic interference. The next stage of the research was to develop an ESS operating process model that takes into account the impact of unintentionally generated electromagnetic interference on the operating process. Introducing the electromagnetic interference impact coefficient enables a rational selection of solutions aimed at protecting against electromagnetic interference through the application of technical and organizational measures.

FEM analysis of the opposed-piston aircraft engine block

An important aspect of aircraft engine design is weight minimization. However, excessive weight reduction may reduce mechanical strength of the engine. This is especially important for aero-engines due to consequences of engine failure in flight. The article presents the results of the FEM opposed-piston diesel engine block model tests. The tested engine is a PZL-100 two-stroke three-cylinder aircraft engine with two crankshafts and six pistons. Air is supplied via a mechanical compressor and a turbocharger. Stress in the engine block is induced by the operating process of the engine block. The pressure in the combustion chamber of the analyzed engine is 13 MPa. The pistons in one of the cylinders are then near their TDC, the deflection angle of the connecting rods is small so almost the entire piston force is transferred to the crankshafts and then to the main bearing supports. This results in the occurence of a tensile force for the engine block applied in the bolt holes of the shaft supports. The calculation results are presented as stress and displacement distributions on the surface and selected block sections. The maximum values on the outer surfaces of the block occurred in the area of the compressor attached to the block and reached 39 MPa. Maximum stresses were, however, observed inside the block on the air and exhaust flow separators between the cylinder liners. The stress value on the outlet side reached 44 MPa.

Diagnostics of the Excessive Wear of the Machine on a Model of Developmental, Progressive Interactions Between Diagnostic Signals and Rotation Speed Signals

In the machine operating process, there are certain interactions between its operational use and wear. The current wear is increased by the current intensity of operational use, and usable potential is reduced by the current wear rate. In the diagnostic inference process, static characteristics and trajectories of state from the experiment are compared with different matrices determined for various assumed configurations of changes. As a result, the approximated diagnosis is created. This method is not universal. It applies only to the continuous progressive state, more or less increased wear rate of the machine.

Dynamic analysis of detumbling a rotating satellite using flexible deceleration rod

Malfunctioning satellites are generally non-cooperative tumbling objects. Due to their complex tumbling motion, it is essential to stabilize the target within an acceptable rotating range in the pre-capture phase. In contrast to contactless methods, contact methods based on flexible devices are efficient and can generate sufficient operating torque through flexible contact. However, accurate dynamic analysis of the operation is challenging because of two limitations. It is difficult to obtain a high-efficiency description of the large deformation arising from the operating process. Moreover, the contact between a flexible device and a tumbling object is hard to detect efficiently. This paper proposes a method for detumbling a free-floating rotating satellite; it uses a flexible rod to contact the solar array of the target. The absolute nodal coordinate formulation is first applied to a rod-contact detumbling model in simulation to describe the large deformation of the rod precisely with a low computational burden. Next, a two-step method to detect the contact is employed to pinpoint the contact point and speed up the simulation: coarse detection in the contactless phase and fine detection in the contact phase. Finally, the feasibility of the contact detumbling method is verified. In addition, through the further analysis of the contact process, some characteristics of this kind of strategy are studied for the first time.

Operational Analysis of Fire Alarm Systems with a Focused, Dispersed and Mixed Structure in Critical Infrastructure Buildings

The article presents issues regarding the impact of operating conditions on the functional reliability of representative fire alarm systems (FASs) in selected critical infrastructure buildings (CIB). FAS should operate correctly under variable environmental conditions. FASs ensure the safety of people and CIB. Operational measurements for 10 representative systems were conducted in order to determine the impact of environmental conditions on FAS reliability. Selected operational indices were also determined. The next stage involved developing two models of representative FASs and the availability, pre-ageing time and operating process security indices. Determining operational indices is a rational selection of FAS technical and organizational solutions that enables the reliability level to be increased. Identifying the course of the FAS operating process security hazard changes in individual system lines, particularly at the initial operation stage, enables people that supervise the operation to affect operating parameters on an ongoing basis. The article is structured in the following order: issue analysis, FAS power supply in CIB, operational test results, selected FAS operating process models, determination of operational and security indices, and conclusions.

Forecast on Lenovo Futures by Analyzing its Internal Operations as Well as the Current Environment

During the difficult time of COVID-19, many businesses in different industries have experienced an economic downturn, causing their future development uncertain to foreseen. The research on the future trend of the IT industry is important because the technologic companies are dependent on customers that either the companies' internal features and external environment can influence people's buying powers. This paper chose Lenovo, a Chinese technologic company that dominates the global market, from the IT industry to analyze its strengths and weakness, as well as the impact of the current situation. This paper looked at Lenovo's financial data and stock price, along with Lenovo's strategies and operating process, to identify Lenovo's present-day situation. Although Lenovo holds a strong position in the global market right now, with the ongoing unfavorable environment such as the trade war between U.S. and China and the rampant of counterfeits, Lenovo is facing threats of losing its stock price. This paper contains a detailed analysis of Lenovo's strengths and weaknesses and the environment it has to deal with. The paper provides evidence to predict Lenovo's future development and suggestions to expand the existing market.

Waste heaps in the urban environment as negative factors of urbanization

Urbanization in Ukraine has led to the development of the Lviv-Volyn coal basin. One of the main negative factors in the operation of coal basins are mine dumps. In addition to environmental hazards, waste heaps of coal mines violate the attractiveness and aesthetics of towns. The wastewater from waste heaps is a secondary factor in reducing the environmental safety of the coal-mining region. These waters are concentrated at the foot of landfills forming the man-made reservoirs. The research presents the negative factors of mine dumps and the results of physical and chemical analysis of subtericone wastewater and its impact on environmental pollution. It is established that the most polluted is the wastewater from waste heaps of the Mezhyrichanska mine which is caused by its operating process. The man-made polluted wastewater from heaps is a secondary factor in reducing the level of ecological danger of the coal-mining region. These waters are concentrated at the foot of landfills in the form of man-made reservoirs. The aim of the research is to indicate the negative factors of urban waste heaps by studying the physical and chemical properties of underspoil waters within the cities of Chervonograd and Novovolynsk.

Research on the Controlling Process in Autonomous Driving

With the development of science and technology, self-driving automobile will become increasingly available in the future, and our lives will become more convenient with them. Autocar is in an area of robotics, belonging to the service field. It can be used to make our lives better and reduce the cost of human driving the car, thus will have a great effect on human’s life. However, people do not understand the mechanism of self-driving quite clearly, it is necessary to present some basic operating process and related algorithms of the automatic cars. Meanwhile, in order to show how a self-driving car could control itself using various sensors and algorithms, which is also the basic idea of the automobile company to make a new autocar. Different sensors that are able to detect the behavior of the self-driving cars are used in this paper to fit in different algorithm that follows the principles of motion and robotics. It is concluded that the car could theoretically drive safely, and could avoid crashing to other cars, people or barriers with the safety algorithm. Also, the car could follow the traffic rules properly and plan the most efficient route to get to the final location.

Experimental and thermal investigation with optimization on friction stir welding of nylon 6A using Taguchi and microstructural analysis

Friction stir welding is an environmentally friendly process of joining due to the non-usage of flux, or any shield gas. Therefore, this article proposes an experimental and thermal investigation with optimization technique for studying the process of FSW on nylon 6A or polycaprolactam polymer composite plates. Specifically, the influence of input operating process parameters such as tool rotational speed (TRS), feed rate, and pitch values on the output response parameters like ultimate tensile strength (UTS), and hardness of welded joints is examined. In addition, L27 orthogonal array of Taguchi approach is employed for the optimization of design experiments of FSW parameters. The experimental setup is carried out with various process parameter combinations like 500, 1000, and 1500 rpm as TRS, 30, 40, and 50 mm as feed rate by varying the pitch values as 1, 2, and 3 mm. Further, the analysis of variance (ANOVA) also employed for finding the significant parameters of input process using the regression analysis equations. Finally, microstructural analysis is used to assess the mixing or dispersing uniformity of composites effectively. The experimental and optimum FSW parameters for maximum UTS are obtained at a feed rate of 30 mm/min, tool pitch of 3 mm, and the TRS of 500 rpm.

RESEARCH ON OPTIMIZING THE OPERATION OF SHIPS IN CONTAINER TERMINALS

The time allotted to a single ship at berth varies greatly depending on the characteristics of the ship, the volume of cargo and its specifications.. Taking into account the service time and the problem of terminals by overcrowding of waiting ships and available berths (which may vary in number, depending on the size of ships already berthed), the average waiting time is calculated and obtained. The operating process is usually sequential, ie each type of cargo is stacked separately from the other types. For this reason, the operating time was considered to consist of four other indicators, which correspond to the main types of cargo of Ro-Ro / Ro-Pax ships: complete trucks, semi-trailers, • passenger cars, vehicles as goods themselves. Also, the time of operation of the goods by the dockers can be formulated by two other different terms: the time related to the ship and the time in the terminal. In this context, we intend to analyze the capacity of the terminal in Constanța Port.. Two different scenarios are considered: a more "common" case for the studied terminal with 40 semi-trailers and 80 trucks to be unloaded and the same amount to be loaded and an "extreme" case in which all goods are composed of semi-trailers ( 160 plus 160 in total). By using simulation models, the values for the optimal quay time were obtained, in relation to the number of units for loading data in the specified scenarios. Using modeling algorithms, we obtain reports of situations that include tables and graphs that allow the optimization of terminal operation.