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The problem of leak detection in water pipeline network can be solved by utilizing a wireless sensor network based an intelligent algorithm. A new novel denoising process is proposed in this work. A comparison study is established to evaluate the novel denoising method using many performance indices. Hardyrectified thresholding with universal threshold selection rule shows the best obtained results among the utilized thresholding methods in the work with Enhanced signal to noise ratio (SNR) = 10.38 and normalized mean squared error (NMSE) = 0.1344. Machine learning methods are used to create models that simulate a pipeline leak detection system. A combined feature vector is utilized using wavelet and statistical factors to improve the proposed system performance.

The paper proposes a design and construction of a special plated capacitor exhibiting very good high-frequency characteristics. The capacitor is designed to minimize the parasitic parameters like ESR (equivalent series resistance) and ESL (equivalent series inductance) and to be suitable for power industry applications. The paper describes the fabrication process and discusses technical issues related to technology of manufacturing and assembling. It also provides an experimental verification and the quality evaluation based on frequency characteristics compared to existing commercial high-quality capacitor.

The road safety management methodology should be based on a system approach. This means that the road transport must be formalized as a complex system (CS), and then safety can be interpreted as an emergent feature of such a system. Road accidents should be interpreted as "organizational accidents". They should be studied using concepts such as "normal accident theory" (NAT) and "highly reliable organization" (HRO). The main purpose of the article is to show the usefulness of these concepts for the road safety and risk management, especially in Polish conditions. The system approach to road safety research (and transport safety) will allow for the better safety results.

The presented work was directed to develop the dynamic performance of an electro-hydraulic proportional system (EHPS). A mathematical model of the EHPS is presented using electro- hydraulic proportional valve (EHPV) by Matlab-Simulink, which facilitates the simulation of the hydraulic behavior inside the main control unit. Experimental work is done and the closed loop system is designed using the linear variable displacement transducer sensor (LVDT). The controller of the system is an Arduino uno, which is considered as a processor of the system. The model is validated by the experimental system. The study also presents a real time tracking control method, based on pulse width modulation, by controlling the speed of the actuator to achieve the position tracking with minimum error and low transient time, by applying the constant input signal 50mm the transient time was 0.9 seconds and the error 1.8%.

The rapid development of transport, the widespread introduction of modern transport technologies, close cooperation with Russia, China and other neighboring countries, will allow Kazakhstan to become a serious player in the transportation market between Europe and Asia in the coming years. Such existing transport potential directly affects the economic growth of the country which will lead to high living standard. The global movement towards digitalization is transforming the logistics industry, as well. The "digit" changes the channels of movement of goods, delivery formats and management processes. Development of e - commerce and the increasing supply requirements - multichannel, responsiveness, transparency, accuracy - stimulate retailers and logistics operators to increase efficiency of processes and introduce new technologies. Therefore, the ways of prosperity of Kazakhstani economy, through digitalization of logistics processes is considered in this article.

Asian countries such as China, Malaysia, India or Bangladesh belong to the largest producers of consumer goods in the world that is mainly transported by container vessels to other parts of the world. One of the busiest maritime trade route is the route between Europe and Asia. It leads through the North Pacific, Indian and the North Atlantic Oceans and their seas. There is also an alternative trade route that runs along the coast of the Russian Federation across the Arctic Ocean. On one hand the ice in this area is gradually declining due to global warming, on the other hand the duration of navigation times is being extended for several months of the year. One of the advantages of this route is the reduction of sailing times between Asian and European maritime ports. The basic goals of the paper are to focus on the current transport situation on this trade route and a new trade route that leads along the coast of Russia.

The  public  service  system  serves  population  spread  over  a  geographical  area from a given number of service centers. One of the possible approaches to  the  problem  with  two  or  more  simultaneously  applied  contradicting  objectives  is  determination  of  the  so-called  Pareto  front,  i.e.  set  of  all  the  feasible non-dominated solutions. The Pareto front determination represents a crucial computational deal, when a large public service system is designed using  an  exact  method.  This  process  complexity  evoked  an  idea  to  use  an  evolutionary  metaheuristic,  which  can  build  up  a  set  of  non-dominated  solution  continuously  in  the  form  of  an  elite  set.  Nevertheless,  the  latter  approach does not assure that the resulting set of solutions represents the true Pareto front of the multi-objective problem solutions. Within this paper, authors  deal  with  both  approaches  to  evaluate  the  difference  between  the  exact and heuristic approaches.

This paper presents an approach to automatically detect the position of the Wi-Fi access points. It uses Wi-Fi received signal strength as well as some characteristics of the buildings such as the height of the building and the movement direction of the user to detect the position of the access points. This approach comprised of two phases: in phase one, a dynamic threshold is computed for each detected access point using the highest received signal strength. Then the threshold is used to detect a small area surrounding the access point. In phase two, it detects the position of the access point by monitoring the angle between the user and the access point, if the angle is in a certain range, then the position of the access point is detected. The experiments results show a high accuracy achieved by the proposed approach. Moreover, the results show that the proposed approach is promising.

The article presents results of scientific and experimental studies of the authors on operation of the tank equipment for ultrasonic purification of exhaust gases of internal combustion engines designed to reduce environmental pollution.
The scheme of the experimental device implementing the principle of the tank equipment operation for ultrasonic cleaning of the motor vehicles exhaust gases is presented; the obtained experimental data of ultrasonic coagulation processes were processed and analyzed. Empirical relationships of the coagulation coefficient and its rate of change are derived from experimental data.

The article presents an assessment of the state of safety on Polish roads in the period 2004-2018 in terms of changes that occurred after Poland's accession to the EU. The number of vehicles in the period in question was analyzed and the annual growth of the number of vehicles of the main types was assessed. Analysis of changes in the length of the most important road types was carried out. The number of accidents and fatalities was analyzed and the changes in this area were assessed. The statistical decrease in the number of accidents and fatalities, as well as a very strong correlation between them, were confirmed. It was indicated in which groups of accidents the fatality risk is the highest. The paper presents a summary of the types of roads on which traffic accidents and fatal traffic accidents occurred. Shares of these roads were determined, indicating that the most dangerous roads in Poland are the two-way, two-lane roads.

This paper displays the design and application of a model that simulates the queuing system of a fictional post office. Starting point for solving more complicated optimization tasks is to create a system model that consists of elements of reality and the relationships between these elements. The key part of the paper includes the model of a queuing system of a post office created in Anylogic simulation software. The model of the post office displays post office with 5 postal counters, a certain input flow and a certain service time with an exponential probability distribution. The model also includes statistics and cost calculation.

Presented paper deals with energy flow control of an electric vehicle with multiple energy storages. For efficiency control of energy flow is necessary to know the traction profile of the route. The Global Positioning System is used for observation of the traction profile. The first of the proposed algorithms uses the whole traction profile of a predetermined route, so the control algorithm can determine when the use of energy of the secondary energy storage is useful. The second proposed algorithm uses the GPS to determine the traction profile from routes stored in memory. If the route is not predetermined, or found in the memory of stored routes, the last algorithm controls the energy flow, based on the current of the primary energy storage. For verification of the proposed algorithm for control of the DC/DC converter, motor with inverter was replaced by the programmable power supply and programmable electronic load. The final evaluation shows that the proposed algorithm with the predetermined route saves about 5% more energy than the basic algorithm based on the battery current.

The article presents the concept of building and controlling a Bricklaying Robotic System (BRS). The research presents the design process and how to control a four-cylinder electro-hydraulic servo drive system. The article presents a mathematical model and optimizes the process of aligning the mobile support platform of the masonry robot. The lifting mechanism was presented and its kinematic analysis performed. The mathematical model of the hydraulic system was described. The control system, designed for the masonry robot lifting platform, includes position errors for a single drive axis and synchronization errors between the axes.

This research was aimed to enhance the cryptospatial with geospatial blockchain based on a point in polygon test. Ripple Protocol Consensus Algorithm (RPCA) was used for developing a blockchain. The steps taken include: (1) Data from the surveyors were entered using application connected to the transaction set; (2) The transaction set sent data to the transaction proposal; (3) The transaction proposal will distribute to every connected validating of nodes for executing the smart contract with the point in a polygon test method; (4) If the process succeeded with the maximum fault tolerance of 20%, then the node records a new chain to the ledger. This method is faster than Practical Byzantine Fault Tolerance (PBFT) blockchain for approximately 26% to add a new chain in the ledger and for 52% to decrypt the blockchain with a mobile device. The result of this process is a cryptospatial coordinate for the cultural heritage tourism.

The authors propose the use of ultrasonic radiation to clean the exhaust gases of internal combustion engines of the solid particles. An experimental stand and research results are presented, proving the possibility and efficiency of using the process of ultrasonic cleaning of exhaust gases due to the process of the solid particles coagulation. The authors received a corresponding patent, the efficiency of which has been proven by results of the conducted research.

The presented paper focuses to rotating components of mechanical constructions. The problem of the spatial combined bending-gyratory vibration and calculation of the Eigen frequencies is studied. The model of Cardan Mechanism is solved by the transfer matrix method. Transfer matrices were derived for shaft, concentrated mass and elastic bearing. The physical and mechanical properties of each part of the mechanism are hidden in these matrices. A procedure for calculating Eigen frequencies was proposed.

At present, the issue of public safety in the production and manipulation of hazardous chemicals deserves more attention, since various major accidents such as fires, explosions and toxic gas releases take place frequently. The issue of prevention of emergency events has become more and more topical. The growing amount of hazardous substances transported leads to increased risk of emergencies. In order to reduce this risk in the transport of hazardous substances, a number of technical, operational, traffic and safety conditions and requirements must be fulfilled. These all contribute to the reduction of hazards and risks. The aim of the presented article was to determine the extent of the danger zone in the event of a gasoline leak due to a traffic accident in a built-up urban area with a high frequency of traffic and population movement.

This paper discusses impact of changes in the load size and distribution in passenger cars on geometry of the suspension and steering systems. It was found to have a major impact on the road safety. The research was carried out with the four most popular suspension system designs used in modern passenger cars, i.e. multi-link suspension on both front and rear axles, only on the front axle, only on the rear axle and a simple suspension design for both front and rear axles. Eight load variants were used for the tests. Changes in the following wheel geometry parameters were identified: toe-in and camber angles of all the wheels and castors for the front wheels. The numerical relationships were determined between the load distribution and sizes and changes in suspension and steering systems in passenger cars. It was found that cars with multi-link suspension in both front and rear axles adapt best to changes in weight and load distribution.

Understanding the term hacking as any unconventional way of interacting with some system it is easy to conclude that there are enormous number of people who hacked or tried to hack someone or something. The article, as result of author research, analyses hacking from different points of view, including hacker's point of view as well as the defender's point of view. Here are discussed questions like: Who are the hackers? Why do people hack? Law aspects of hacking, as well as some economic issues connected with hacking. At the end, some questions about victim protection are discussed together with the weakness that hackers can use for their own protection. The aim of the article is to make readers familiar with the possible risks of hacker's attacks on the mobile phones and on possible attacks in the announced flood of the internet of things (next IoT) devices.

Nowadays the protection of life, health and property of individuals is in the centre of public interest. There is not a distinction between the provision of such protection by private or public sector. The private security services play an important role in protection of persons and property. The subjects of protection are not only people and property, but also sensitive information which is relevant for the state interest or business entities. Based on research, the private security services do not make a selection of employees systematically. One of the reasons is the absence of an analysis of candidates' personal competencies which should take into account the requirements of the protected subject. The aim of the article is therefore a software solution for modelling the personal competencies of applicants for the job in private security services.

Development of public transportation is meant to bridge the divide between cities and encourage development results. The inter-city transportation opens up opportunities for the inter-city trade, reduces costs and increases labor mobility, thereby promoting the inter-city development opportunities. This study uses the factor and cluster analyses. Analysis of factors is performed to determine the most dominant factors. The cluster analysis is used to identify the advantages and disdvantages of five modes of transport, namely taxi, trade rail, economy bus, mini bus, and executive bus. This study aims to determine the perception of users of Medan-Pematang Siantar route service. The results of this study show that there are five dominant factors that are considered before the service users decide on the mode of transport to use, namely the comfort factor, which is the most important consideration, followed by the time factor, cost factor, accessibility factor and safety factor.

The article presents and describes research results concerning determination of an impact of the ionospheric correction upon the positioning accuracy of an aircraft. The main objective of examinations was to verify three ionospheric models (the Klobuchar model, SBAS model and IONEX model) in determining aircraft coordinates. In the framework of the conducted simulations, the authors determined the aircraft coordinates by means of the SPP code method in the GPS system. The article presents a comparison of the determined aircraft coordinates in the SPP code method in relation to an accurate solution in the RTK-OTF differential technique. Based on the obtained results, it was found that e use of the SBAS and IONEX model is exploited to improve the positioning accuracy of an aircraft in relation to the Klobuchar model, from 20% to 72%, in the geocentric XYZ frame. The obtained findings of a simulation indicate that the ionospheric correction in the SBAS and IONEX models may be used to improve the performance of aircraft coordinates in air navigation.

The electric parking brake (EPB) system as the complex mechatronic system consists of the actuators that generate the clamping force necessary to hold the vehicle safe, the conventional calipers that convert clamp force into brake torque, electronic hardware with the Electronic Control Unit (ECU), cable harness and switches and especially the control software providing the functions that the driver will experience. Like most of the modern automotive components, the EPB is equipped with embedded electronic systems that include ECU, electronic sensors, signals, bus systems, and coding. Due to the complex application in electrical, electronics and programmable electronics, the need to carry out detailed safety analyses that are focused on the potential risk of malfunction is crucial for automotive systems. This paper describes a possible division of the EPB sub-functions between the supplier the wheel brakes and the supplier which supplying the ECU. Functional safety must be a guarantee with concerning the overall vehicle system. Functional safety is according to the requirements of the ISO 26262 standard and in the context of this paper relates solely to the E/E components (electrical and/or electronic) of the EPB. This paper covers the hazard analysis and risk assessment relevant to the EPB control software, and the derived allocation of ASIL risk levels to the EPB software elements of the functional architecture of the EPB.

This article describes one of the possible ways for improving the energy efficiency of shunting diesel locomotives. It means a replacing a traditional traction electric transmission with a diesel generator set with a hybrid transmission with a free-piston internal combustion engine and a linear generator. The absence of a crankshaft in an internal combustion engine makes it possible to reduce thermal and mechanical losses, which, in turn, leads to an increase in the efficiency of traction electric transmission of the diesel locomotive.

The paper deals with a modeling and simulation of the direct AC-AC propulsion system and compares two matrix converter concepts with five-phase traction induction motors (IM) for the hybrid electric vehicle (HEV). The simulation results of [3x5] matrix converter and 4Q-converter are done using Matlab-Simulink environment. Part I deals with a theoretical study of converter concepts for hybrid electric vehicle, since the configurations of [3x5]+[0x5] matrix converters with five-phase motor(s) have not been analyzed so far. Based on simulation results the comparison and evaluation of the property and quality of the quantities of different type of the matrix powertrain are discussed in Part II.

Nowadays, in all the cities, there is an acute problem of a lack of parking spaces. The number of vehicles are becoming more and more larger, not only in megacities, but in small cities of the country, as well and there are no more parking places - the pace of solving the problem is several times slower than the rate of the transport growth among the citizens. The article is dedicated to the determination of the optimum sizes parking place for designing vehicles on a parking space, which is an element of the roads. The optimum amount parking places are determined on examples of the passenger cars and trucks. The results of research on dimensioning of parking spaces and recommendations to use the results for design of objects of transportation infrastructure are presented. According to the research, authors included the term "design vehicle" and gave its definition. The authors developed a template for 7 types of design vehicles and their sizes and also recommended sizes for longitudinal parking for each of their design vehicles. The optimum parking plot angles are determined, as well.

Presented paper deals with possibility of recovery of damaged traction batteries by deep discharge. For the test of proposed charging algorithm, new, unused cell was selected, the deeply discharged condition of which was caused by the self-discharge during the improper storage. The cell had significant damage of package in the central part. For the battery testing, experimental set-up was realized for automated recovering procedure and other tests of cells. For verification of the proposed algorithm, a recovered cell was compared to a reference/new cell by testing the delivered ampere-hours for various discharging current. The final evaluation shows that the proposed algorithm for recovery of the deeply discharged cell can recover up to 70% of the nominal cell capacity.

This study is devoted to determining the geometric, kinematic and dynamic characteristics of a vehicle. To this purpose, it is proposed to use a complex approach applying the models of deformable body mechanics for describing the oscillatory movements of a vehicle and the computer vision algorithms for processing a series of object images to determine the state parameters of a vehicle on the road. The model of the vehicle vertical oscillations is produced by means of the viscoelastic elements and the dry friction element that fully enough represent the behavior of the sprung masses. The introduced algorithms and models can be used as a part of a complex system for monitoring and controlling the road traffic. In addition, they can determine both the speed of the car and its dynamic parameters and the driving behavior of the individual drivers.

This article deals with replacement of the magnetic grippers on the VPO-3-3000 machines with roller grippers. The novelty lies in establishment of dependences characterizing stress and strain in elements of the lifting and straightening devices and in rails during the operation. Reliability of the program for calculating the structural parameters of the lifting and straightening device for the VPO-3-3000 track renewal machine is shown. The developed design of the lifting and straightening device makes it possible to select the rational parameters of technology and the operating mode of the device. This design is recommended for use when developing working bodies for the straightening machines. The article presents calculation of the lifting and straightening device structural elements' strength during operation, in the Ansys WB software package.

This paper presents results of research concerning determination of the GPS reference station coordinates located on the grounds of an EPDE airport in Deblin. The study uses a mathematical model of the PPP measurement technique in order to determine the coordinates of the reference station using the real GPS code-phase observations. The computations of the coordinates of the GPS reference station were carried out in numerical applications CSRS-PPP, APPS and GAPS. In this research was found that the accuracy of finding solutions to the XYZ geocentric coordinates of the reference station REF1 between solutions CSRS-PPP, APPS and GAPS ranges from 0.01m to 0.13m. In addition, the accuracy of determining the XYZ geocentric coordinates from the PPP method related to the GPS differential solution ranged from 0.01m to 0.11m.