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Journal & Issues

Volume 52 (2022): Issue 4 (December 2022)

Volume 52 (2022): Issue 3 (September 2022)

Volume 52 (2022): Issue 2 (June 2022)

Volume 52 (2022): Issue 1 (March 2022)

Volume 51 (2021): Issue 4 (December 2021)

Volume 51 (2021): Issue 3 (October 2021)

Volume 51 (2021): Issue 2 (June 2021)

Volume 51 (2021): Issue 1 (March 2021)

Volume 50 (2020): Issue 4 (December 2020)

Volume 50 (2020): Issue 3 (October 2020)

Volume 50 (2020): Issue 2 (June 2020)

Volume 50 (2020): Issue 1 (March 2020)

Volume 49 (2019): Issue 4 (December 2019)

Volume 49 (2019): Issue 3 (October 2019)

Volume 49 (2019): Issue 2 (June 2019)

Volume 49 (2019): Issue 1 (March 2019)

Volume 48 (2018): Issue 1 (December 2018)

Volume 47 (2018): Issue 1 (December 2018)

Volume 46 (2018): Issue 1 (June 2018)

Volume 45 (2018): Issue 1 (March 2018)

Volume 44 (2017): Issue 1 (December 2017)

Volume 43 (2017): Issue 1 (October 2017)

Volume 42 (2017): Issue 1 (June 2017)

Volume 41 (2017): Issue 1 (March 2017)

Volume 40 (2016): Issue 1 (December 2016)

Volume 39 (2016): Issue 1 (October 2016)

Volume 38 (2016): Issue 1 (October 2016)

Volume 37 (2016): Issue 1 (July 2016)

Volume 36 (2015): Issue 1 (December 2015)

Volume 35 (2015): Issue 1 (November 2015)

Volume 34 (2015): Issue 1 (September 2015)

Volume 33 (2015): Issue 1 (September 2015)

Volume 32 (2014): Issue 1 (December 2014)

Volume 31 (2014): Issue 1 (September 2014)

Volume 30 (2014): Issue 1 (June 2014)

Volume 29 (2014): Issue 1 (March 2014)

Volume 27 (2014): Issue 1 (February 2014)

Volume 26 (2013): Issue 1 (June 2013)

Volume 25 (2013): Issue 1 (March 2013)

Volume 24 (2012): Issue 1 (December 2012)

Volume 23 (2012): Issue 1 (September 2012)

Volume 22 (2012): Issue 1 (June 2012)

Volume 21 (2012): Issue 1 (March 2012)

Volume 20 (2012): Issue 1 (January 2012)

Volume 14-15 (2010): Issue 2010 (December 2010)

Volume 13 (2010): Issue 1 (January 2010)

Volume 11-12 (2009): Issue 1 (December 2009)

Volume 9-10 (2009): Issue 1 (January 2009)

Volume 8 (2008): Issue 1 (December 2008)

Volume 7 (2008): Issue 4 (December 2008)

Volume 6 (2008): Issue 3 (September 2008)

Volume 5 (2008): Issue 2 (June 2008)

Volume 4 (2008): Issue 1 (March 2008)

Volume 3 (2007): Issue 2007 (January 2007)

Journal Details
Format
Journal
eISSN
2083-4608
First Published
26 Feb 2008
Publication timeframe
4 times per year
Languages
English

Search

Volume 50 (2020): Issue 4 (December 2020)

Journal Details
Format
Journal
eISSN
2083-4608
First Published
26 Feb 2008
Publication timeframe
4 times per year
Languages
English

Search

22 Articles
Open Access

Analysis of the Impact of Application of Fuels With Addition of Biocomponents on Functioning of Transport Means

Published Online: 31 Dec 2020
Page range: 1 - 18

Abstract

Abstract

The study describes a method and a model for assessment of the impact of addition of fatty acid methyl esters to fuel oil on selected parameters of transport means. For this purpose, criteria for assessment of operational parameters of the analyzed mixture have been identified. A model has been developed to find out how the values of the analyzed parameters reflect the state of transport means powered by fuel oil mixtures and methyl esters of fatty acids. Ten operational parameters have been accepted for the research object description. The parameter values were measured depending on the analyzed mixture composition. The obtained results allowed to determine the components of the object state vector. The developed model has been verified by application of the method of mean fuzzy diagram.

Keywords

  • fuel oil
  • biocomponent
  • operational parameters
  • assessment model
  • diagram of fuzzy means
Open Access

Risk in Carsharing – Identification and Assessment

Published Online: 31 Dec 2020
Page range: 19 - 30

Abstract

Abstract

The purpose of this article is identification of risks in carsharing and their latter assessment in terms of probability of occurrence, impact on customer relationships, importance of a given category and cost they generate. A way of aggregating various categories of risks into one synthetic indicator in order to prioritize them was proposed. Methodology of the process was based on a methodological triangulation which is based on the following studies – analysis and criticism of literature which helps to place discussed research problem on theoretical basis, qualitative research and observations allowing to identify individual categories of risks and quantitative research enabling the description of given categories of risks by appropriate variables on which further risk modelling is performed. Such research may be a basis to subsequent analysis and be an impulse to an academic debate. Also it may contribute to creation of further studies dealing with the problem of assessment of the risk in concepts related to sharing economy.

Keywords

  • sharing economy
  • carsharing
  • risk assessment
Open Access

Reliability and Failure Studies of Firefighters’ Helmets in Simulated Operational Conditions

Published Online: 31 Dec 2020
Page range: 31 - 40

Abstract

Abstract

The aim of the study was to determinate the fracture mechanism of firefighters’ helmets caused by the impact load in simulated operational conditions. Moreover the aim of the study was to assess the reliability of the personal protective equipment. Tests were conducted with the use of the drop tower system. On each type of helmet 5 impact tests were performed. The active force corresponding to impact energy of 60 J and the passive force (force in the place of the neck spine) was registered. Based on the results, it can be statement that helmets’ structure influences their reliability and values of the active and passive forces. Additionally, the majority of tested helmets exceeded the acceptable threshold values of passive force.

Keywords

  • firefigher’s helmet
  • dynamic loading
  • impact test
  • reliability
  • operational conditions
  • limit and critical loads of the neck spine
Open Access

Reliability and Operational Analysis of an Electronic Security System Taking into Account the Impact of Strong Electromagnetic Pulses

Published Online: 31 Dec 2020
Page range: 41 - 62

Abstract

Abstract

In this article, the authors presented a short historical overview of the visual monitoring systems’ development. Attention was also drawn to the features distinguishing the solutions within this group from other electronic systems. Further, the authors conducted a reliability analysis of selected, sample segments of a CCTV system, at the same out highlighting that such a system – considered globally – is distinguished by a mixed reliability structure. The authors suggested a reliability and operational model for a video surveillance system, which takes into account the impact of strong electromagnetic pulses on a fragment of its transmission channel and the mechanical properties of transmission media.

Keywords

  • reliability and operational analysis
  • electronic security systems
  • strong electromagnetic pulses
Open Access

Possibilities of Using the Type Bypass Air Bleed in a Single-Flow Jet Engine

Published Online: 31 Dec 2020
Page range: 63 - 71

Abstract

Abstract

The paper outlines the analysis dedicated to possibilities of using the type Bypass air bleed in a single-flow jet engine. Attention is focused on development of formulas for key operational parameters of the engine, such as overall work of the thermal cycle, unit thrust and unit consumption of fuel. Simulation and modelling a single-flow jet engine were carried out for the K-15 engine of a Polish make where an air bleeding of that kind is applied. It was confirmed that such engines offer some slight benefits, in particular in terms of cost-efficiency, and such benefits increase in pace with growth of the mass air flow intensity through the bypass channel.

Keywords

  • adaptation engine
  • keywords
  • Bypass air bleed
Open Access

Analysis of Failures of Selected Technical Objects

Published Online: 31 Dec 2020
Page range: 73 - 88

Abstract

Abstract

The article deals with selected issues concerning tests results of failures of selected objects used in the analyzed real technical system. The main operation goal of the analyzed system is to provide passengers with safe transport services within a given quantitative range and over a given territory. The analyzed technical objects were transport means. Transport services were provided along scheduled routes. Selected features and characteristics of vehicle failures have been discussed. Vehicles used in the investigated technical object were disassembled for the needs of the research. Tests were performed with the use of the passive experiment method under real service conditions.

Keywords

  • urban transport
  • reliability
  • damage
  • transport
Open Access

Assessment of Changes in Microstructure and Hardness of Bearing Steel for Operation at a High Temperature Caused by Short-Term Overheating

Published Online: 31 Dec 2020
Page range: 89 - 110

Abstract

Abstract

The paper presented research results of the impact of short-term overheating of samples collected from the outer bearing ring suitable for the operation at elevated temperature installed in the turbine engine on the microstructure and hardness of the material. The samples were annealed at the following temperatures: 500, 600, 700, 800, 900 and 1000°C; and then cooled in still air. Microstructure examinations were conducted under metallographic microscope and transmission electron microscope.

Keywords

  • rolling bearing
  • bearing steel
  • microstructure
  • hardness
  • light microscopy
  • TEM
Open Access

Maintenance Strategies Overlook for Devices Under Operation

Published Online: 31 Dec 2020
Page range: 111 - 124

Abstract

Abstract

An updated systematization of maintenance strategies based on selected transport device exploitation parameters, working in continuous process was presented. The presented framework provides guidelines of assessment methods and an evolution of the way-of-thinking and technological changes in the modern industry related with the maintenance strategies. The paper present also a holistic discussion about the maintenance strategies applicability on overhead operating cranes.

Keywords

  • maintenance
  • devices
  • learning management systems
Open Access

Evaluation of the Impact of Glycol Antifreeze on the Surfaces of Typical Construction Materials of Heat Exchangers

Published Online: 31 Dec 2020
Page range: 125 - 145

Abstract

Abstract

Glycol-based antifreeze liquids are used in two main areas: ICECS and HVAC. The standard research methods and requirements were developed to control the quality of fluids for the internal combustion engine cooling systems. Irrespective of the intended use, fluid tests are conducted with the same methods. This manuscript aims to study two types of antifreeze with standard methods. Then, the analysis was deepened to include microscopic techniques to identify the potential pitting corrosion centres on the surface of the selected metals. It was demonstrated that the application of microscopic techniques could significantly increase the chance to detect potential corrosion centres.

Keywords

  • corrosion pits
  • infrastructure heating systems
  • HVAC systems
  • studies of glycol antifreeze liquids
Open Access

Risk Assessment for the Selected Surface Water Intake

Published Online: 31 Dec 2020
Page range: 147 - 163

Abstract

Abstract

The purpose of the work is to analyze the risk for surface water intake, taking into account factors affecting the water quality. A three-parameter risk definition was proposed. It was found that the analyzed water intake has an efficient system that protects consumers against drinking water of inadequate quality (multibarier system). The task of the water supply company is to maintain its security measures (including a caution and warning station, biomonitoring) in a state of efficiency.

Keywords

  • risk
  • surface water intake
Open Access

The Quality of Video Communication in Encrypted Traffic

Published Online: 31 Dec 2020
Page range: 165 - 180

Abstract

Abstract

The rapid development of network and computer technologies creates opportunities for offering advanced broadband multimedia services to a growing number of end users. Instant messaging and group communication services based on real-time video transmission based on global Internet resources are the most popular. The basic challenge related to the implementation of video transmission services is to ensure an appropriate level of quality and security (Quality & Security). The article presents a multi-criteria assessment of the impact of encryption protocols for multimedia video transmissions on the perceived quality of QoE (Quality of Experience) service implementation. The presented measurement method together with the proposed research methodology create the possibility of determining the likelihood of video service availability with accepted QoE in heterogeneous networks.

Keywords

  • video communication
  • security
  • Quality of Experience
Open Access

Issues of Railway Traffic Control Devices Availability in the Exploitation Process

Published Online: 31 Dec 2020
Page range: 181 - 203

Abstract

Abstract

This article focuses exclusively on the issues of railway traffic control devices availability in traffic management. One of the factors affecting this availability are tests conducted during maintenance or repair works. A review of the literature in the field of test determination methods was conducted. Next, the railway traffic control system was described and the elements influencing availability were defined. Assumptions and an algorithm of the procedure were presented and the method of determining the tests was proposed.

Keywords

  • tests
  • railway
  • control
  • metodology
Open Access

Corrosion Monitoring of Aircraft Based on the Corrosion Prognostic Health Management (CPHM) System

Published Online: 31 Dec 2020
Page range: 205 - 216

Abstract

Abstract

The article presents methods to monitor the actual state of aircraft’s airframe, in particular, the onset of corrosion. The greatest emphasis is put on the “Corrosion Prognostic Health Management” CPHM system. Authors discuss corrosion detection using NDT methods as well as the possibilities of forecasting methods for estimating the onset of corrosion basing on the data gathered by means corrosion sensors. Based on the results of the previous research and analyses, authors focus on monitoring the internal microclimate and the factors causing corrosion in the aspect of damage tolerance operation of the aircraft. The results of the preliminary studies giving credibility to the concepts of predicting corrosion onset in the aircraft structure are presented. Preliminary results of tests carried out in supervised flights are also presented. The final part of the article presents the concept of modernizing the corrosion field site in order to use it in hermetic and non-hermetic tests of aircraft spaces.

Keywords

  • corrosion
  • aircraft
  • non-destructive testing
Open Access

Analysis of measuring apparatus errors using the FAM-C and FDM-A methods

Published Online: 31 Dec 2020
Page range: 217 - 236

Abstract

Abstract

The article discusses the errors of the electronic measuring apparatus built at AFIT using the FAM-C and FDM-A methods, dedicated to monitoring the technical condition of aircraft power units. The basic components and variants of the use of the built electronic apparatus are presented: the optimization of the selection of construction parameters and the change of the error level in the selection of various types of construction of a given system. The influence of external factors on errors of the measuring system was also described, including changes in the amplitude of the electrical power generator output signal and the influence of the carrier frequency depending on the phase configuration of the measuring system. The method of comprehensive checking of electronic measuring equipment for FAM-C and FDM-A methods in laboratory conditions was presented.

Keywords

  • metrology
  • measuring errors analysis
  • zero crossing comparator
  • time base generator
  • FAM-C method
  • FDM-A method
Open Access

Optimization of the Regulated Maintenance Periodicity on Military Equipment Products Operated According to their Technical Condition

Published Online: 31 Dec 2020
Page range: 237 - 249

Abstract

Abstract

The article is dedicated to the optimization problem of the regulated maintenance periodicity for military products operated according to their technical condition. The analytical method of optimization for the exponential law of the time distribution between failures and the numerical optimization method for the diffusion-monotonic law are taken into consideration. The search for the extreme value of the regulated maintenance periodicity for the diffusion-monotonic distribution law was conducted with the use of the numerical method applying Mathcad 15.0. The dependencies of both the technical utilization factor and its derivative on the regulated maintenance periodicity at certain values of the model parameters were obtained.

Keywords

  • optimization
  • diffusion-monotonic distribution
  • type I errors
  • the utilization factor
  • numerical method
Open Access

Planning Supplies in the Enterprise in the Aspect of Reliability

Published Online: 31 Dec 2020
Page range: 251 - 268

Abstract

Abstract

The article presents the example of material needs planning (MRP) methodology in a production company. The example assumes the production technology of three independent products A, B and C exhibiting structural modularity. For calculations, a methodology should be developed for describing products with such a structure that reflects the relationships of individual components used to prepare a delivery schedule. The Microsoft Excel spreadsheet was used as the calculation tool.

Keywords

  • reliability
  • delivery scheduling
  • product structure
  • planning
Open Access

Information system support for military aircraft operations SI SAMANTA as a tool to support logistic resource management

Published Online: 31 Dec 2020
Page range: 269 - 286

Abstract

Abstract

The article addresses the functioning of IT support systems for the implementation of complex processes based on the SI SAMANTA. The paper focused on the supported areas and functions of the IT system. The role of this system in the a/c operation process and its impact on flying safety were determined. The possibilities of IT processing of data and information were characterized, along with their analytical use, e.g. for the assessment of aircraft reliability and maintenance efficiency of the repairs of airplanes and helicopters. The directions that are intended to be developed to increase the usability of the presented system were also discussed.

Keywords

  • IT systems
  • IT support
  • operation
  • aircraft
  • planes and helicopters
  • SI SAMANTA
Open Access

Fatigue Risk Management of the Operator Based on Selected Examples

Published Online: 31 Dec 2020
Page range: 287 - 297

Abstract

Abstract

The article presents issues related to methods of risk management related to operator fatigue. An organization that wants to safely carry out operational tasks need effective methods and tools for risk assessment in safety system to increase the chances and likelihood of the organization achieving its goals. In this case, it is about identifying the risk of fatigue at work, controlling it and minimizing its negative effects. The article presents, on the example of a pilot, the possibilities of managing the risk of fatigue at work, both in the reactive, proactive and predictive dimensions, using selected examples of methods and tools. The summary emphasizes the need for a systemic risk management related to fatigue at work.

Keywords

  • risk management
  • fatigue
  • safety
  • human factor
Open Access

Simulation of a Motor Vehicle’s Motion on the Basis of a Turning with the Steering Wheel Release

Published Online: 31 Dec 2020
Page range: 299 - 308

Abstract

Abstract

In this paper, the selected phenomena related to a motor vehicle’s motion have been considered based on a computer simulation in MSC Adams/Car. The vehicle’s model performed a turning maneuver with the steering wheel release under different road conditions.

All simulations have been performed based on the sports two-seater vehicle’s model, at the initial speed of 70 km/h on the flat and randomly uneven road. This enabled us to observe the selected phenomena along the road long enough to relate them to different aspects of road traffic safety in unusual situations. For uneven road, the same profiles were assumed for the left and the right wheel of the vehicle, with two coefficient values determining the maximum height of these irregularities.

Keywords

  • vehicle dynamics
  • turning maneuver
  • lateral motion
Open Access

Cyber security as a foundation for the security of critical infrastructure in the context of modern threats

Published Online: 31 Dec 2020
Page range: 309 - 320

Abstract

Abstract

The article’s goal is to outline the most characteristic features of the problem of the growing role and predominance of cybersecurity as a key element in the functioning of critical infrastructure and the possibilities of the best solutions. Due to the fact that from all systems of critical infrastructure, the most important for the proper functioning of the economy and society is the system of energy and fuel supply. The article will analyze past, present and future threats and evolution of tools to combat them. Particular emphasis will be placed on the characteristics of these threats, especially cyberattacks, as well as the most effective ways of counter-actions. The article might be an element of the debate on the critical impact of cyberattacks on critical infrastructure, which has a direct impact on national security.

Keywords

  • cybersecurity
  • critical infrastructure
Open Access

Legal basis of cybersecurity on the background of polish and UE legislation

Published Online: 31 Dec 2020
Page range: 321 - 329

Abstract

Summary

The last decades have brought about the rapid development of information technology, which was reflected in all areas of social life and economic. Unfortunately, the ongoing digitization and the presence of individuals, private entities as well as countries in the network makes them exposed to new types of threats that have never been seen before. The perpetrators of these threats may be individuals, organized criminal groups or foreign country interviews. Threats and vectors of attacks has many forms, and their evolution continues all along with the progressive development of broadly understood cyberspace. In order to be able to effectively fight with the increasing threats in cyberspace, not only technical and organizational measures are needed, but also the formal and legal framework to combat cyber-attacks. In this article, the authors discuss the legal comparison of the basics of cyber security against the Polish background and EU legislation.

Keywords

  • cyber-attacks
  • cyber-security
  • legal grounds for responding to cyber-attacks
Open Access

Aspects of Utilizing Burnishing for Reconditioning Machine Components

Published Online: 31 Dec 2020
Page range: 331 - 352

Abstract

Abstract

The paper presents exemplary application of burnishing treatment as a technological process of reconditioning machine components. Empirical research of burnishing treatment was conducted on the most common cylindrical surfaces which are widely used in machine construction, for example in drive shafts of centrifugal pumps. Experimental tests were carried out and determined the influence of burnishing technology on strengthening the surface layer of cylindrical samples made of unalloyed C45stainless steel. Burnishing was conducted by means of NK-01 roller burnisher, made in the Department of Marine Maintenance at Gdynia Maritime University. The burnishing is normally applied in manufacturing as well as reconditioning machine elements used in machine industry, metallurgic industry, power engineering industry or shipping and aviation industry where the safety and reliability of machine work is decisive.

Keywords

  • burnishing
  • reconditioning
  • centrifugal pump shafts
22 Articles
Open Access

Analysis of the Impact of Application of Fuels With Addition of Biocomponents on Functioning of Transport Means

Published Online: 31 Dec 2020
Page range: 1 - 18

Abstract

Abstract

The study describes a method and a model for assessment of the impact of addition of fatty acid methyl esters to fuel oil on selected parameters of transport means. For this purpose, criteria for assessment of operational parameters of the analyzed mixture have been identified. A model has been developed to find out how the values of the analyzed parameters reflect the state of transport means powered by fuel oil mixtures and methyl esters of fatty acids. Ten operational parameters have been accepted for the research object description. The parameter values were measured depending on the analyzed mixture composition. The obtained results allowed to determine the components of the object state vector. The developed model has been verified by application of the method of mean fuzzy diagram.

Keywords

  • fuel oil
  • biocomponent
  • operational parameters
  • assessment model
  • diagram of fuzzy means
Open Access

Risk in Carsharing – Identification and Assessment

Published Online: 31 Dec 2020
Page range: 19 - 30

Abstract

Abstract

The purpose of this article is identification of risks in carsharing and their latter assessment in terms of probability of occurrence, impact on customer relationships, importance of a given category and cost they generate. A way of aggregating various categories of risks into one synthetic indicator in order to prioritize them was proposed. Methodology of the process was based on a methodological triangulation which is based on the following studies – analysis and criticism of literature which helps to place discussed research problem on theoretical basis, qualitative research and observations allowing to identify individual categories of risks and quantitative research enabling the description of given categories of risks by appropriate variables on which further risk modelling is performed. Such research may be a basis to subsequent analysis and be an impulse to an academic debate. Also it may contribute to creation of further studies dealing with the problem of assessment of the risk in concepts related to sharing economy.

Keywords

  • sharing economy
  • carsharing
  • risk assessment
Open Access

Reliability and Failure Studies of Firefighters’ Helmets in Simulated Operational Conditions

Published Online: 31 Dec 2020
Page range: 31 - 40

Abstract

Abstract

The aim of the study was to determinate the fracture mechanism of firefighters’ helmets caused by the impact load in simulated operational conditions. Moreover the aim of the study was to assess the reliability of the personal protective equipment. Tests were conducted with the use of the drop tower system. On each type of helmet 5 impact tests were performed. The active force corresponding to impact energy of 60 J and the passive force (force in the place of the neck spine) was registered. Based on the results, it can be statement that helmets’ structure influences their reliability and values of the active and passive forces. Additionally, the majority of tested helmets exceeded the acceptable threshold values of passive force.

Keywords

  • firefigher’s helmet
  • dynamic loading
  • impact test
  • reliability
  • operational conditions
  • limit and critical loads of the neck spine
Open Access

Reliability and Operational Analysis of an Electronic Security System Taking into Account the Impact of Strong Electromagnetic Pulses

Published Online: 31 Dec 2020
Page range: 41 - 62

Abstract

Abstract

In this article, the authors presented a short historical overview of the visual monitoring systems’ development. Attention was also drawn to the features distinguishing the solutions within this group from other electronic systems. Further, the authors conducted a reliability analysis of selected, sample segments of a CCTV system, at the same out highlighting that such a system – considered globally – is distinguished by a mixed reliability structure. The authors suggested a reliability and operational model for a video surveillance system, which takes into account the impact of strong electromagnetic pulses on a fragment of its transmission channel and the mechanical properties of transmission media.

Keywords

  • reliability and operational analysis
  • electronic security systems
  • strong electromagnetic pulses
Open Access

Possibilities of Using the Type Bypass Air Bleed in a Single-Flow Jet Engine

Published Online: 31 Dec 2020
Page range: 63 - 71

Abstract

Abstract

The paper outlines the analysis dedicated to possibilities of using the type Bypass air bleed in a single-flow jet engine. Attention is focused on development of formulas for key operational parameters of the engine, such as overall work of the thermal cycle, unit thrust and unit consumption of fuel. Simulation and modelling a single-flow jet engine were carried out for the K-15 engine of a Polish make where an air bleeding of that kind is applied. It was confirmed that such engines offer some slight benefits, in particular in terms of cost-efficiency, and such benefits increase in pace with growth of the mass air flow intensity through the bypass channel.

Keywords

  • adaptation engine
  • keywords
  • Bypass air bleed
Open Access

Analysis of Failures of Selected Technical Objects

Published Online: 31 Dec 2020
Page range: 73 - 88

Abstract

Abstract

The article deals with selected issues concerning tests results of failures of selected objects used in the analyzed real technical system. The main operation goal of the analyzed system is to provide passengers with safe transport services within a given quantitative range and over a given territory. The analyzed technical objects were transport means. Transport services were provided along scheduled routes. Selected features and characteristics of vehicle failures have been discussed. Vehicles used in the investigated technical object were disassembled for the needs of the research. Tests were performed with the use of the passive experiment method under real service conditions.

Keywords

  • urban transport
  • reliability
  • damage
  • transport
Open Access

Assessment of Changes in Microstructure and Hardness of Bearing Steel for Operation at a High Temperature Caused by Short-Term Overheating

Published Online: 31 Dec 2020
Page range: 89 - 110

Abstract

Abstract

The paper presented research results of the impact of short-term overheating of samples collected from the outer bearing ring suitable for the operation at elevated temperature installed in the turbine engine on the microstructure and hardness of the material. The samples were annealed at the following temperatures: 500, 600, 700, 800, 900 and 1000°C; and then cooled in still air. Microstructure examinations were conducted under metallographic microscope and transmission electron microscope.

Keywords

  • rolling bearing
  • bearing steel
  • microstructure
  • hardness
  • light microscopy
  • TEM
Open Access

Maintenance Strategies Overlook for Devices Under Operation

Published Online: 31 Dec 2020
Page range: 111 - 124

Abstract

Abstract

An updated systematization of maintenance strategies based on selected transport device exploitation parameters, working in continuous process was presented. The presented framework provides guidelines of assessment methods and an evolution of the way-of-thinking and technological changes in the modern industry related with the maintenance strategies. The paper present also a holistic discussion about the maintenance strategies applicability on overhead operating cranes.

Keywords

  • maintenance
  • devices
  • learning management systems
Open Access

Evaluation of the Impact of Glycol Antifreeze on the Surfaces of Typical Construction Materials of Heat Exchangers

Published Online: 31 Dec 2020
Page range: 125 - 145

Abstract

Abstract

Glycol-based antifreeze liquids are used in two main areas: ICECS and HVAC. The standard research methods and requirements were developed to control the quality of fluids for the internal combustion engine cooling systems. Irrespective of the intended use, fluid tests are conducted with the same methods. This manuscript aims to study two types of antifreeze with standard methods. Then, the analysis was deepened to include microscopic techniques to identify the potential pitting corrosion centres on the surface of the selected metals. It was demonstrated that the application of microscopic techniques could significantly increase the chance to detect potential corrosion centres.

Keywords

  • corrosion pits
  • infrastructure heating systems
  • HVAC systems
  • studies of glycol antifreeze liquids
Open Access

Risk Assessment for the Selected Surface Water Intake

Published Online: 31 Dec 2020
Page range: 147 - 163

Abstract

Abstract

The purpose of the work is to analyze the risk for surface water intake, taking into account factors affecting the water quality. A three-parameter risk definition was proposed. It was found that the analyzed water intake has an efficient system that protects consumers against drinking water of inadequate quality (multibarier system). The task of the water supply company is to maintain its security measures (including a caution and warning station, biomonitoring) in a state of efficiency.

Keywords

  • risk
  • surface water intake
Open Access

The Quality of Video Communication in Encrypted Traffic

Published Online: 31 Dec 2020
Page range: 165 - 180

Abstract

Abstract

The rapid development of network and computer technologies creates opportunities for offering advanced broadband multimedia services to a growing number of end users. Instant messaging and group communication services based on real-time video transmission based on global Internet resources are the most popular. The basic challenge related to the implementation of video transmission services is to ensure an appropriate level of quality and security (Quality & Security). The article presents a multi-criteria assessment of the impact of encryption protocols for multimedia video transmissions on the perceived quality of QoE (Quality of Experience) service implementation. The presented measurement method together with the proposed research methodology create the possibility of determining the likelihood of video service availability with accepted QoE in heterogeneous networks.

Keywords

  • video communication
  • security
  • Quality of Experience
Open Access

Issues of Railway Traffic Control Devices Availability in the Exploitation Process

Published Online: 31 Dec 2020
Page range: 181 - 203

Abstract

Abstract

This article focuses exclusively on the issues of railway traffic control devices availability in traffic management. One of the factors affecting this availability are tests conducted during maintenance or repair works. A review of the literature in the field of test determination methods was conducted. Next, the railway traffic control system was described and the elements influencing availability were defined. Assumptions and an algorithm of the procedure were presented and the method of determining the tests was proposed.

Keywords

  • tests
  • railway
  • control
  • metodology
Open Access

Corrosion Monitoring of Aircraft Based on the Corrosion Prognostic Health Management (CPHM) System

Published Online: 31 Dec 2020
Page range: 205 - 216

Abstract

Abstract

The article presents methods to monitor the actual state of aircraft’s airframe, in particular, the onset of corrosion. The greatest emphasis is put on the “Corrosion Prognostic Health Management” CPHM system. Authors discuss corrosion detection using NDT methods as well as the possibilities of forecasting methods for estimating the onset of corrosion basing on the data gathered by means corrosion sensors. Based on the results of the previous research and analyses, authors focus on monitoring the internal microclimate and the factors causing corrosion in the aspect of damage tolerance operation of the aircraft. The results of the preliminary studies giving credibility to the concepts of predicting corrosion onset in the aircraft structure are presented. Preliminary results of tests carried out in supervised flights are also presented. The final part of the article presents the concept of modernizing the corrosion field site in order to use it in hermetic and non-hermetic tests of aircraft spaces.

Keywords

  • corrosion
  • aircraft
  • non-destructive testing
Open Access

Analysis of measuring apparatus errors using the FAM-C and FDM-A methods

Published Online: 31 Dec 2020
Page range: 217 - 236

Abstract

Abstract

The article discusses the errors of the electronic measuring apparatus built at AFIT using the FAM-C and FDM-A methods, dedicated to monitoring the technical condition of aircraft power units. The basic components and variants of the use of the built electronic apparatus are presented: the optimization of the selection of construction parameters and the change of the error level in the selection of various types of construction of a given system. The influence of external factors on errors of the measuring system was also described, including changes in the amplitude of the electrical power generator output signal and the influence of the carrier frequency depending on the phase configuration of the measuring system. The method of comprehensive checking of electronic measuring equipment for FAM-C and FDM-A methods in laboratory conditions was presented.

Keywords

  • metrology
  • measuring errors analysis
  • zero crossing comparator
  • time base generator
  • FAM-C method
  • FDM-A method
Open Access

Optimization of the Regulated Maintenance Periodicity on Military Equipment Products Operated According to their Technical Condition

Published Online: 31 Dec 2020
Page range: 237 - 249

Abstract

Abstract

The article is dedicated to the optimization problem of the regulated maintenance periodicity for military products operated according to their technical condition. The analytical method of optimization for the exponential law of the time distribution between failures and the numerical optimization method for the diffusion-monotonic law are taken into consideration. The search for the extreme value of the regulated maintenance periodicity for the diffusion-monotonic distribution law was conducted with the use of the numerical method applying Mathcad 15.0. The dependencies of both the technical utilization factor and its derivative on the regulated maintenance periodicity at certain values of the model parameters were obtained.

Keywords

  • optimization
  • diffusion-monotonic distribution
  • type I errors
  • the utilization factor
  • numerical method
Open Access

Planning Supplies in the Enterprise in the Aspect of Reliability

Published Online: 31 Dec 2020
Page range: 251 - 268

Abstract

Abstract

The article presents the example of material needs planning (MRP) methodology in a production company. The example assumes the production technology of three independent products A, B and C exhibiting structural modularity. For calculations, a methodology should be developed for describing products with such a structure that reflects the relationships of individual components used to prepare a delivery schedule. The Microsoft Excel spreadsheet was used as the calculation tool.

Keywords

  • reliability
  • delivery scheduling
  • product structure
  • planning
Open Access

Information system support for military aircraft operations SI SAMANTA as a tool to support logistic resource management

Published Online: 31 Dec 2020
Page range: 269 - 286

Abstract

Abstract

The article addresses the functioning of IT support systems for the implementation of complex processes based on the SI SAMANTA. The paper focused on the supported areas and functions of the IT system. The role of this system in the a/c operation process and its impact on flying safety were determined. The possibilities of IT processing of data and information were characterized, along with their analytical use, e.g. for the assessment of aircraft reliability and maintenance efficiency of the repairs of airplanes and helicopters. The directions that are intended to be developed to increase the usability of the presented system were also discussed.

Keywords

  • IT systems
  • IT support
  • operation
  • aircraft
  • planes and helicopters
  • SI SAMANTA
Open Access

Fatigue Risk Management of the Operator Based on Selected Examples

Published Online: 31 Dec 2020
Page range: 287 - 297

Abstract

Abstract

The article presents issues related to methods of risk management related to operator fatigue. An organization that wants to safely carry out operational tasks need effective methods and tools for risk assessment in safety system to increase the chances and likelihood of the organization achieving its goals. In this case, it is about identifying the risk of fatigue at work, controlling it and minimizing its negative effects. The article presents, on the example of a pilot, the possibilities of managing the risk of fatigue at work, both in the reactive, proactive and predictive dimensions, using selected examples of methods and tools. The summary emphasizes the need for a systemic risk management related to fatigue at work.

Keywords

  • risk management
  • fatigue
  • safety
  • human factor
Open Access

Simulation of a Motor Vehicle’s Motion on the Basis of a Turning with the Steering Wheel Release

Published Online: 31 Dec 2020
Page range: 299 - 308

Abstract

Abstract

In this paper, the selected phenomena related to a motor vehicle’s motion have been considered based on a computer simulation in MSC Adams/Car. The vehicle’s model performed a turning maneuver with the steering wheel release under different road conditions.

All simulations have been performed based on the sports two-seater vehicle’s model, at the initial speed of 70 km/h on the flat and randomly uneven road. This enabled us to observe the selected phenomena along the road long enough to relate them to different aspects of road traffic safety in unusual situations. For uneven road, the same profiles were assumed for the left and the right wheel of the vehicle, with two coefficient values determining the maximum height of these irregularities.

Keywords

  • vehicle dynamics
  • turning maneuver
  • lateral motion
Open Access

Cyber security as a foundation for the security of critical infrastructure in the context of modern threats

Published Online: 31 Dec 2020
Page range: 309 - 320

Abstract

Abstract

The article’s goal is to outline the most characteristic features of the problem of the growing role and predominance of cybersecurity as a key element in the functioning of critical infrastructure and the possibilities of the best solutions. Due to the fact that from all systems of critical infrastructure, the most important for the proper functioning of the economy and society is the system of energy and fuel supply. The article will analyze past, present and future threats and evolution of tools to combat them. Particular emphasis will be placed on the characteristics of these threats, especially cyberattacks, as well as the most effective ways of counter-actions. The article might be an element of the debate on the critical impact of cyberattacks on critical infrastructure, which has a direct impact on national security.

Keywords

  • cybersecurity
  • critical infrastructure
Open Access

Legal basis of cybersecurity on the background of polish and UE legislation

Published Online: 31 Dec 2020
Page range: 321 - 329

Abstract

Summary

The last decades have brought about the rapid development of information technology, which was reflected in all areas of social life and economic. Unfortunately, the ongoing digitization and the presence of individuals, private entities as well as countries in the network makes them exposed to new types of threats that have never been seen before. The perpetrators of these threats may be individuals, organized criminal groups or foreign country interviews. Threats and vectors of attacks has many forms, and their evolution continues all along with the progressive development of broadly understood cyberspace. In order to be able to effectively fight with the increasing threats in cyberspace, not only technical and organizational measures are needed, but also the formal and legal framework to combat cyber-attacks. In this article, the authors discuss the legal comparison of the basics of cyber security against the Polish background and EU legislation.

Keywords

  • cyber-attacks
  • cyber-security
  • legal grounds for responding to cyber-attacks
Open Access

Aspects of Utilizing Burnishing for Reconditioning Machine Components

Published Online: 31 Dec 2020
Page range: 331 - 352

Abstract

Abstract

The paper presents exemplary application of burnishing treatment as a technological process of reconditioning machine components. Empirical research of burnishing treatment was conducted on the most common cylindrical surfaces which are widely used in machine construction, for example in drive shafts of centrifugal pumps. Experimental tests were carried out and determined the influence of burnishing technology on strengthening the surface layer of cylindrical samples made of unalloyed C45stainless steel. Burnishing was conducted by means of NK-01 roller burnisher, made in the Department of Marine Maintenance at Gdynia Maritime University. The burnishing is normally applied in manufacturing as well as reconditioning machine elements used in machine industry, metallurgic industry, power engineering industry or shipping and aviation industry where the safety and reliability of machine work is decisive.

Keywords

  • burnishing
  • reconditioning
  • centrifugal pump shafts

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