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Main purpose of this paper is to point out the problems considering the modern scientific usage of methods, ways and approaches, including the crime investigation of traffic accidents-collisions. We want to show the basic need of experienced traffic crime detective, his/her deep knowledge of the whole issue - the process of the traffic accident perpetrating as a complex process with the direct impact on the traffic crime detective work, which could be used in the process of the clearance the case, the video-record output created by program PC CRASH as the virtual element of legal evidence, enabling deeper knowledge of the whole process.

The paper deals with the study of stress corrosion cracking of high-strength steels in an aqueous environment with a varying pH factor ranging from 5.5 to 12.0. Steels were studied after quenching and tempering, one of the steels was prone to temper embrittlement. Single-edge notched pre-cracked specimens were used for the experiments. Changes in the pH factor at the crack tip were measured using an antimony electrode. The pH factor values at the crack tip dropped to 2.0. Steel prone to temper embrittlement showed significantly shorter incubation period and more accelerated development of corrosion process compared to the optimized heat treatment of the second steel. Proneness to intergranular fracture was observed close to the fatigue crack tip. The obtained results expand the existing knowledge about localized corrosion processes leading to the refinement of the stress corrosion cracking model when changing the pH factor on the crack tip.

This work presents results of strength analyses of a modified freight wagon bogie frame. It consists of two main parts. The first part is addressed to introduction of the structure of a freight wagon bogie frame. It is a modified frame structure, which reflects current requirements of modern railway transport means. The conditions for rail vehicles approval and the main load cases, which every bogie frame must meet for commissioning, are described. The next part deals with computer modelling and analyses of this bogie frame. Strength analyses were performed using the FE method and they were focused on the assessment of stresses in the frame structure. Loads definition and the method of calculation were based on valid norms and standards.

Communication is very important for people. Means of communication are constantly increasing and new forms, and ways of communication are developing because of technological innovations. The paper is focused on a part of the marketing research of customers´ contentment and their preferences in order to determine their requirements and preferences in the field of mobile and data services of mobile operators. Results and conclusions of this paper should help mobile operators to identify customers´ needs and allow to customize their service offers. The level of competition in the selected market is relatively low, despite the fact that it is growing nowadays. The first part of the paper focuses on the theoretical basis of customer satisfaction in the telecommunications market and the second part on preferences survey and customers´ contentment in the market and its evaluation results.

This paper deals with description and application of the Wigner-Ville transformation for vibration analysis. This transformation belongs to the group of non-linear time-frequency processes. Thanks to its properties, it may be successfully used in the area of non-stationary and transitional signals describing various natural processes. The use in the field of the railway constructions testing represents a quite an interesting application area of the transformation. This paper contains mathematical analysis of the transformation, a case study and practical experience obtained and recommendations for its practical use.

The paper follows previously published papers in Communications - Scientific Letters of the University of Zilina No. 4/2014, No. 4/2015 and No. 4/2016, where were presented the results of the diagnostics of the track geometry of the experimental sections surrounding the portals of a new building of the Tunnel Turecky vrch. Based on the data obtained by comprehensive diagnostics, there can be stated that the problematic section in the slab track are the transition areas allowing the transfer of the vehicle between the line structures with a different bending stiffness. The comprehensive diagnostics was realised by the continuous method (measuring trolley KRAB), the results of which were verified by the results of the measuring car of ZSR and by the geodetic monitoring of the layout of the track, as well. Mathematical modelling of the transition areas was realized in the environment of the software ANSYS with the aim to optimise the structural solution of the existing transition areas, as well as of in the future built ones, within the modernization of the railway infrastructure of the Slovak Republic. The model of the existing transition area was structurally optimised -models were realised with application of the stiffening rails and with usage of the under sleeper pads. The model of the current state and the models of the optimised structural solutions of the transition areas were subsequently compared by the values of the vertical displacement, vertical speed and vertical acceleration.

Electrochemical characteristics of AZ31 magnesium alloy after impacting by ultrasonic impact peening (UIP) were measured in order to evaluate its effect on corrosion resistance of mentioned alloy. For this purpose, potentio-dynamic polarization (PD) tests and electrochemical impedance spectroscopy (EIS) of ground and impacted samples were performed in 0.1 M NaCl solution at the temperature of 22±2 °C after 5 minutes of potential stabilization. The obtained PD curves were analysed using the Tafel extrapolation method and data from EIS measurements in form of Nyquist plots were quantified by the equivalent circuit method. The results showed clearly that application of the UIP significantly deteriorated corrosion resistance of AZ31 alloy in the chosen testing solution.

The main topic of the submitted paper is intelligent logistics and its integration into production systems. In the beginning, the problem that lies in the inadequate knowledge of the internal state has been defined. The new society-wide trends that will originate in a few years are also outlined. Those trends will affect factories and their logistics systems on a large scale. Therefore, it is necessary to have a strategy that takes these new trends into consideration. In this manuscript, is described a strategy for intelligent production systems, as well as technologies for different types of production-logistic strategies. Many of these technologies can be applied together with the Digital Twin. The Digital Twin is a new concept in the field of designing production and logistics systems in the factory. Finally, we provide a description of the implementation of the Digital Twin into the production and logistics system.

In this paper are presented results of mechanical properties evaluation of the thin sheets welds made of the S960MC TMCP steel, which were executed using the GMAW procedure with different process parameters. The microstructural changes in the heat affected zone (HAZ) were evaluated, as well. The microstructural observation revealed significant changes in the HAZ and the three main zones, coarse grain, fine grain and intercritical (CGHAZ, FGHAZ and ICHAZ) were identified in the HAZ for both sets of tested welding parameters. Evaluation of the micro-hardness showed significant reduction of the micro-hardness in the ICHAZ, for both tested states, and the ICHAZ was identified as the most critical area of the whole welded joint. Results of the tensile tests revealed significant reduction of mechanical properties regardless of the welding parameters.

Optimization of parameters of central gears of a planetary gearbox was performed in this study. Since the optimization of multi-performance characteristics is more complex compared to optimization of a single-performance characteristics, the Taguchi-Grey analysis was used. That approach combines the Taguchi orthogonal array L27 with the Grey relational analysis to determine the influence of the material, module and gear width on the safety coefficient of the planetary gearbox. A Grey relational grade obtained from the Grey relational analysis is used as the performance characteristics in the Taguchi method and Analysis of variance (ANOVA). The optimal combination of parameters for the safety coefficient values was obtained, when the value of the Grey relational grade is 1. Based on the ANOVA analysis, it was established that the most influential parameter is the module, then the gear width and the least influential one is the material.

The paper deals with the influence of physical-metallurgical factors on resistance of the X52 and X70 steels in accordance with API 5L to sulphide stress cracking. The resistance against this kind of damage is relatively clearly claimed by usually used approach in this field by the tensile strength of steel, its hardness level, respectively. However, the experimental results had shown that the microstructural parameters are also the significant factors, which affect the resistance of steels to sulphide stress cracking. It was found that the quenching and tempering can significantly increase the resistance to sulphide cracking as in the case of hydrogen induced cracking. It would be appropriate to re-evaluate the material selection process that recommends to use the steels not exceeding approved strength limit in a case of the sulfane environments where the risk of the sulphide stress cracking exists.

The paper deals with the issue of delays of public transport vehicles at the signal controlled junctions. Based on the road traffic survey results, the average values of vehicle delays were determined. By using those values, it is possible to define time savings for the vehicles and mainly for passengers that are transported. The time savings were determined based on the relationships and coefficients defined in this paper.

The paper presents the results of the APVV project - Regional dimensions of knowledge economy, which was solved in the Department of Communications, Faculty of Operation and Economics of Transport and Communications, University of Zilina during 2008 - 2011. The paper briefly describes logistics sector and ICT sector in the Zilina region and their knowledge management. Significant results of the project were achieved through knowledge biography, which maps creation, processing and dissemination of knowledge. Based on this methodology the case studies in selected logistics and ICT enterprises in the Zilina region were created. The results of sectoral analysis and knowledge biographies of enterprises resulted into finding that knowledge is the most strategic "material"; learning is a critical process for maintaining competitiveness of enterprises and that relevant aspects together create key mechanism for regional differentiation.

Small and medium-sized enterprises (SMEs) are very sensitive to changes in the business environment which after a certain time are always reflected into quantitative characteristics of this sector. In 2013, we accomplished a statistical survey on current trends in the field of business risks for SMEs in selected regions of the Czech Republic and Slovakia. In this article we want to analyze the effects of selected risks of the survey with respect to the length of the small and medium-sized business enterprises in the Zilina region. SMEs should be aware of their risks, mainly due to their importance in the economic system of the Slovak Republic, which mostly lies in their inconsiderable share to create job positions in the region.

This paper deals with the size of the forces affecting the vehicle during the transportation on a flatbed truck, railway wagon or container. It is necessary to secure the vehicle against these forces properly in order to prevent vehicle´s replacement. The laboratory measurements were performed in order to find out the size of coefficient of friction between the tire and the vehicle´s loading area. During the measurements, vehicle had different gears in order to determine to what extent the size of mechanical resistances affects the fixing and securing the vehicle against its replacement on the loading area. However, this paper does not propose the solution for securing the passenger vehicle on the loading area of a truck, railway wagon or container.

This article is aimed on reporting procedure in emergency situation used in multi-national environment. It is based on real procedures, documents and instructions, which are usually used in all kinds of emergency assets, especially during the activities of multi-national joint forces. The first impulse for creating this procedure started in armed task forces and due to the great effect fluently increased to the civilian sector. The article is a basic instruction how to simply ensure information flowchart among all the elements and secure quick reaction on developing crisis situation.

Modern day society wants to create optimal living conditions for its citizens and to ensure constant sustainable development. This objective cannot be achieved without reaching the required level of perceived security in complex. One of the areas that threaten the lives and property of people and are harmful for the environment is the anthropogenic crisis phenomena, which also include industrial accidents. Prevention of these accidents and subsequent reaction are the key issues considering adjustment of the level of security not only for the citizens of Slovakia, the European Union but also worldwide. The article focuses on the problem of prevention and the way how to deal with the issue in the Slovak Republicas well as on the fulfilment of the requirements in this field which emerge from our membership in the EU. The Faculty of Special Engineering at the University of Zilina deals with partial issues which are necessary to be solved by the approved project APVV - 10 Complex model of risk assessment of industrial processes. Partial results of the project, which is in the second year of its solution, are listed in the text below.

The paper illustrates the theoretical basis of a new device called MUMS - Modular Underground Monitoring System - and one of its applications. MUMS has been designed for monitoring of underground displacements through a continuous and automated data acquisition system. MUMS instrumentation can be used to monitor the deformation of natural and artificial slopes as well as geotechnical structures. The device consists of a series of nodes located at known distances along a connecting rope and is installed within a vertical borehole. Each node measures its local rotation relative to the vertical axis by means of a 3D micro electro-mechanical acceleration sensor (MEMS). The direction cosines of each node are calculated in order to determine the 3D shape and deformation of the entire borehole. The paper illustrates an interesting application of MUMS in natural slopes and points out the benefits of the system.

In this contribution we discuss selected geometrical mappings that, although uncommon in practice, are important and irreplaceable in some areas of engineering, architecture and art (scenography, embossing, panoramic cinematography).

The paper deals with topical information from the area of crisis information support. The contributing authors work at three co-operating universities where the subject of transport support in crises is tackled. At present the electronic support of crisis management in transport is necessary prerequisite for the functioning of transport system under both common and emergency situations. The outcomes of scientific research projects are new even from a broader European perspective. The preparation of complex automated information system for remote management of crisis situations in rail transport is new and has not been published yet. The outcomes of extensive analysis, gradually developed methodologies and data sets are presented in the paper together with the current outcomes regarding the electronic support of crisis management in transport.

In this article we describe a project "Competency Based e-Portal of Security and Safety Engineering" - eSEC portal approved by The Education, Audio-visual and Culture Executive Agency (EACEA), developed in the period between 10/2009 and 10/2012. The eSEC portal is one of 10 centralised multilateral projects approved in 2009 by EACEA and only one with the University of Zilina as a coordinator, with total budget 356.138 Euros. The EACEA is responsible for the management of certain elements of the EU's programs in the fields of education and culture. The idea for the eSEC project originated from the demand to increase the quality of education in the field of security and safety. One of the key problems of the education is disparity between the knowledge received from educational institutions and the practical requirements. It is necessary to redefine how students are prepared for the challenges of the labour market: identifying competencies that are currently indemand and how it would be possible to link the educational systems of various institutions more efficiently. The aim of the eSEC project was to develop the competencies of students, teachers, researchers and professionals working in the field of security and safety, within the EU and the world. To achieve these objectives, an electronic portal was developed at www.esecportal.eu. The portal was launched in May 2012, hopefully starting the way to become an established and well known Internet portal on the security and safety education.

The paper deals with problems of influence of parallel parking on urban roads for road traffic safety. It shortly refers to evaluation of normative principles related to parking of road vehicles in the Czech Republic.It presents the results of analysis of traffic participant behavior on the particular section of inhabited area by use of video analysis of conflict situations. Thus it is pointed out to a possibility of application of this methodology in execution of safety inspections on roads, for example.

Existing buildings are responsible for over 40 % of the world´s total primary energy consumption (data from IEA). The EU adopted the Energy Performance of Buildings Directive [1], which obliges Member States to reduced 20 % in greenhouse gas (GHG) emissions by 2020 compared with 1990 levels, a 20 % cut in energy consumption through improved energy efficiency by 2020 and a 20 % increase in the use of renewable energy by year 2020. The Directive also requires Member States to ensure that, after year 2020, all new buildings in the EU will have to consume “nearly zero” energy.
Slovakia has excellent availability of wood and therefore it would be appropriate to build the family houses as wooden houses in combination with light sandwich envelope structures.
However, more extensive use is still hampered by the prejudice about disadvantages of wooden structures, which are from the past.
This paper evaluates the results of calculation and measuring two wooden family houses, located in the Slovak Republic, from the perspective of low energy construction and sustainable development principles. The first one is a wooden house constructed in the year 2000 and built under valid thermo-technical standards. The second one is a newly built passive family house. The results of energy calculations and measurements under real conditions in situ are presented. The calculations of the theoretical evaluation are appraised in accord with the Energy Performance of Buildings Directive 2002/91/EC [2] and EU and Slovak standards or codes.
Environmental evaluations are performed for existing buildings and the results are confronted with the values from various buildings based on different materials (lightweight concrete blocks and lime-sand bricks).

The Memory of Slovakia Centre of Excellence (MSCOE) is a project of the University of Zilina, under the scientific and organisational auspices of the Faculty of Humanities implemented from 2010 until 2013. The paper contains information about the project, some outcomes and specialisation of scientific and innovation activities. It describes priorities for research and innovation in the MSCOE, especially optimisation of mass digitisation technology, integrating processes of mass digitisation and conservation of textual materials and optimisation of linguistic solutions in mass digitisation and the best possible preparation of digital content for use.

This paper describes a way to better navigate in an ever increasing number of standards in the field of ITS. Short overview about fundamental ITS models is presented, the principles of related knowledge system are described. Ontology approach is used, especially as domain-oriented ITS ontology, where a new hybrid method is explained.

Air transport was traditionally highly regulated, fragmented and protected. With European air transport market deregulation in the mid 1980s also airports could respond to new factors. Methodology developed within the FAST project analyzed evolution of airport strategies potential in the forthcoming decade in the frame of new airport typology reflecting different strategies depending on the airport size, market type and market potential.

In self-ignition engines with Common Rail direct fuel injection, premature destruction of injectors has been observed. New elements are also touched by the problem. In order to solve it, a group of international experts in the area have gathered. Destroyed piezoelectric and electromagnetic injectors' elements of BOSCH, DELPHI, DENSO, have been examined. Mechanical damages influencing electronic diagnostic signal have been presented. Some system solutions possible to perform as far as diagnostic prevention is concerned have been described. Some useful electronic diagnostic methods of fuel system, signal analysers: RMOG and ERDIA PRO, have been presented.

Over the past few years an increasing number of companies certified according to the requirements of ISO 9001:2008 for Quality Management System (QMS) but also according to the requirements of other standards, for example environmental management system according to ISO 14001:2004 (EMS) and / or a management system for Occupational Health & Safety Management System, according to OHSAS 18001:2007, or other standards (ISO 22000, ISO 27000, etc.) can be seen in industrial sector and in services as well. Integration of management systems has become a key aspect of more sustainable management of a company. The aim of paper is to (1) better explain role of management systems implementation in enterprises, (2) point out necessity of their integration, (3) analyze common items of particular management systems, which is inevitable to their further integration, (4) point out some benefits and obstacles linked with integration.

The executive dashboard systems are a mainstream business intelligence technology. The main idea behind the executive dashboard systems is to deliver information about status of the organization by means of simple, abstract measures of performance and intuitive visualizations. One of the key concerns is preventing information overload. This is achieved by identifying key performance indicators - a set of measures that summarize the key aspects of the organization's performance. This paper investigates the application of the concept of the executive dashboard systems to the context of public emergency management. We identify the key differences between development of executive dashboard systems for profit-oriented organizations and for the multi-organizational network of the public emergency-management organizations. Based on these differences we deliver a set of implementation guidelines.

This paper reviews the key protocols used for multimedia delivery both over privately owned managed IP Networks such as IPTV and public non-managed IP Networks such as WebTV. Within these two worlds, the choice between protocols is based on the characteristics of the multimedia service required, the media server and the client's receiver.Users have different expectations of these two delivery platforms and also of different output devices such as TV, PC, tablet or mobile phone. In an IPTV environment, which is a paid-service, users demand the Quality of Service (QoS) they pay for; different quotas provide different services to users. On the other hand, with WebTV, which is a free service, clients have lower quality expectations.There are multiple multimedia delivery systems used across both platforms, using different protocols to deliver multimedia from server to one or multiple clients. These include Real-Time Protocol (RTP), Real-Time Control Protocol (RTCP), Real-Time Streaming Protocol (RTSP), Real-Time Messaging Protocol (RTMP), Hypertext Transfer Protocol (HTTP), HTTP Live Streaming (HLS) and Microsoft Smooth Streaming Protocol (MS- SSTR).RTP, RTCP and RTSP are the main protocols used in IPTV while RTMP, HTTP, HLS and MS-SSTR are protocols used mainly for WebTV. This paper will explore the main differences and similarities between them and the reasons behind the choice of one or the other. This review paper also briefly outlines a testbed being developed by the authors to synchronise media streams using a subset of these protocols.