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Increase Safety of Traffic Control on the Minor Railway-Tracks

Author(s): Jan Slezak,Juraj Spalek / Language(s): English Issue: 2A/2011

The paper aims at detecting the existing safety risks on the minor railway-tracks being operated in accordance with the provision CD-D3 of the Czech Railways, and at providing the solutions and technologies suitable for the mentioned minor railway-tracks. These tracks are currently equipped with out of date safety related systems monitoring the railway, whose operation depends purely on human factor. The latest railway accidents were reported just on these low traffic frequency tracks.

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LPG Concentration Measurement in Vehicles Transporting Dangerous Goods

Author(s): Martin Vestenicky,Peter Vestenicky / Language(s): English Issue: 2A/2011

This paper describes the design of intelligent sensor unit for LPG (Liquefied Petroleum Gas) concentration measurement in the air. The sensor unit is a part of sensor network which has been designed for vehicles transporting dangerous goods. The described sensor unit uses sensor element based on SnO2 structure which is vapoured on the aluminum substrate. Main part of the paper is focused on hardware solution of the sensor unit, signal processing applied on signal from its sensor element, compensation of air temperature and relative humidity influence on the sensor resistance and description of its application layer communication protocol.

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Dynamic Properties of the Railway Track

Author(s): Milan Moravčík / Language(s): English Issue: 3/2007

The paper is focused on different aspects of track dynamics and train-track interaction. The dynamic modeling of railway track response and of the interaction of vehicle and track at low and mid frequencies, that are significant for the track deterioration, is presented. Dynamic properties of the track structure as a whole is described and evaluated including the dynamics of compound train-track system. The dynamic amplification resulting from the simulated passage of the locomotive of the type E 499.0 (85t) is presented.

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Reinforced Subbases and Application of Other Chosen Parameters in Sleeper Subgrade Dimensioning

Author(s): Libor Izvolt,Jan Kardos,Martin Mecar / Language(s): English Issue: 3/2007

The paper focuses on reinforced subbases which are frequently applied to modernised railway tracks of Slovak Railways (ŽSR) despite certain theoretical and normative deficiencies. Based on the evaluation of laboratory measurements other parameters which are to be taken into consideration when dimensioning a sleeper subgrade construction are specified.

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Relation of Temperature Changes in Asphalt Pavements to Pavement Bearing Capacity Evaluation

Author(s): Jozef Komacka,Martin Korenko,Jaroslav Piala / Language(s): English Issue: 3/2007

Temperature changes in asphalt pavements have to be taken into account at the diagnostic and evaluation process of pavements bearing capacity. Theoretical calculations resulting from general theory are not suitable for the practical use. Therefore the experimental test section with flexible and semi-rigid pavement was built and the temperatures were measured at different depths. The examples of typical temperature gradients for the hot summer and cold spring day are presented and their similarities are stated. The development of the simple method for the determination of mean temperature of pavement asphalt layers is described and the correction values relative to the temperature of pavement surface are shown for the time interval from 2000 to 800 and the asphalt layers thickness of 210 mm.

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Effects of Structural Integrity on Improving the Resistance to Dynamic Loads

Author(s): Emília Juhásová / Language(s): English Issue: 3/2007

The paper deals with the approaches to the dynamic response analysis when non-linear response of the structure including its partial damage is expected. This concerns the building and other structures executed near transport lines and possibly subjected to seismic effects from transport or earthquakes. Seismic response is here analysed under the action of near field earthquake that was considered and applied as 6DOF seismic input and 2DOF seismic input. A typical reinforced concrete frame with masonry infills was chosen as the prototype for the experimental tests and next analysis. Two storey one bay 1:1 model was tested on a large shaking table with sequentially increasing intensity of seismic input. The specimen was designed according to the rules of Eurocode 8 and the masonry infill was strengthened with horizontal polymer grids placed in prescribed bed joints. The non-linear behaviour is analysed in view of pushover analysis approach and limits of interstorey drift. General behaviour of the analysed frame showed reasonable seismic resistance that was supported by sufficient integrity and limited cracks appearance.

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The Transport-Production Coordination Problem

Author(s): Jaroslav Janáček / Language(s): English Issue: 3/2007

Vehicle route planning process, which follows a transportation problem solution, often provides a system of cyclic routes of vehicles. This system should cover transportation demands of individual network nodes within a middle term period. Due to non-uniform demand distribution over the period, a new problem emerges in particular parts of the period. This problem consists in balancing the sub-period demands and frequencies, with which the individual routes are performed. This new problem denoted as the transport-production coordination problem is studied in this contribution. We described the problem by mathematical programming tools and proposed a decomposition method to enable the problem decomposition to irreducible sub-problems. The individual types of the problem were studied and particular solving algorithms were designed. To complete our approach to this NP-hard problem, we developed an exchange heuristic and explored its properties. The associated computational study was performed with several series of the irreducible sub-problems, which were solved by the exchange heuristic and, simultaneously, they were solved to optimality by the universal optimization environment Mosel. The results were used for evaluation of the heuristic quality and time consumption.

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Evaluation of Comfort for Passengers of Railway Vehicles

Author(s): Juraj Gerlici,Tomáš Lack,Zuzana Ondrova / Language(s): English Issue: 4/2007

The passenger's complex sensation felt during the application of oscillations and/or inertia forces, via the whole-body transmission is defined and evaluated with the help of comfort indexes such as a mean comfort; mean permanent sensation evaluated according to the measurement procedures for the indexes, and comfort on curve transition, discomfort due to a perceived curve entry or reverse transmission, or comfort on discrete events - discomfort, due to a perceived transient oscillation on a straight track, curves and curve transitions. In the text the authors deal with mean comfort evaluation and its qualification with the help of the Comfort Indexes.

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Increase in Road Transport Safety - Way to Reduction of External Costs

Author(s): Alica Kalašová / Language(s): English Issue: 3/2005

Satellite navigation and prepared navigation system Galileo is the key technology that has to open the gate to new applications. It has to ensure Europe to not be too dependent (in term of economic and safety) on nonmember states of EU, to establish new applications and create new markets with integrated navigation and communication services. In our article we will deal with the opportunities that the new navigation system Galileo will offer for the road transport.

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Contact Area and Normal Stress Determination on Railway Wheel/Rail Contact

Author(s): Tomáš Lack,Juraj Gerlici / Language(s): English Issue: 2/2005

It is important to study the field of railway wheel /rail contact area from the point of view of stress distribution for further investigation of running behavior of a vehicle when running on a rail track. There is a contact of two spatial geometrically defined bodies, which have characteristic material properties, by a power effect of a vehicle through the wheel on the rail. The contact point is transformed into the contact area as a result of the pressure of the bodies against each other. It is possible to acquire the image of the contact area and the stress which appears at the contact as a result of the application of a known calculation method or to set up own calculation methods. The paper deals with theoretical grounds of two computational methods. They are the Hertz method and strip method (according to Johnson [5]). The results of the contact area and normal stress numerical computation made by authors of the paper are stated and compared with the above mentioned methods and the results of the contact area and normal stress numerical computation made by the authors of the paper are stated and compared with the methods in references [7].) The contribution of the paper is to present the authors’ computational results and compare the results with published results of other authors [7]. The authors reached the results with the support of their own computational program. The results are the base for other tangential contact stress research computations and base for other vehicle dynamics simulation computation in the future.

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Hull Structural Scantlings of the Golden Series Otoryacht

Author(s): Peter Patek / Language(s): Slovak,English Issue: 1/2001

The paper describes the procedures for scantlings of some hull structural elements from FRP materials. The solution and software are based on the rules of classification societies GL-BV-RINA. It allows to estimate the optimal skin-plating thickness and other dimensions of the stiffeners. These procedures are applied for design of the large high-speed craft Golden Series designed for the open-sea class. The luxurious yachts built in Bratislava shipyard for foreign customer.

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Unified View of Optimization of Transport Supply

Author(s): Jan Černý / Language(s): English Issue: 4/2000

The paper presents so called transport supply optimization problem, which can be generally formulated as to find an optimum covering of demand. The types of supply can be very different (as goods-supply, transport-supply etc). In spite of variability of real supply optimization problems they have several common properties. For the presented problem it formulates continuous and discrete model, shows that both models have similar structure and presents solutions of corresponding mathematical problems.

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Profile of the Best World Logistics Practice

Author(s): Jaroslav Král / Language(s): Slovak,English Issue: 4/2000

The paper deals with an issue of supply chain management that is a trend in integrated logistics enterprise management. It gives a synthesised view on current logistics management practice of the best World companies. It defines reasons of supply chains genesis, conditions of an implementation and environment of operations improvements. Also it justifies an importance of information technologies, information systems and the Internet place here. The paper indicates the most important problem for solving is supply chain inventory to be minimised.

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Maintaining Inter-Vehicle Spacing - Using Synergetic Effects between Rail and Road Traffic!

Author(s): Günter Hertel,Hans-Eberhard Siebert,Richard Vogel / Language(s): English Issue: 4/1999

Now as ever, transportation services are a decisive criterion of an economy. This constitutes the background for dealing with the various routing and protection principles for the two important land-based traffic systems: namely, road and rail transport. The objective is to determine how the two systems could benefit from the respectively chosen approaches to a solution and which future operating concepts this makes possible. Whether in rail or road traffic, inter-vehicle spacing directly effects several quality criteria of the transport process, and vehicle throughput. The various theoretically possible and practically applied principles for maintaining inter-vehicle spacing will be described and assessed with regard to occupied time, safety, and throughput. Today, various principles are used in both system which is attributable in part to the historical development of the system but also to the possibility of supporting the system through technical assistance systems. For both systems the possible maximum traffic throughput is considered depending on maintaining inter-vehicle spacing. Synergy potential can be used through an interdisciplinary approach to detection and classification of traffic scenarios. In the future, vehicle electronics will be developed with the same objectives and similar outline conditions. Rail traffic then can profit from the series effect of road traffic and thus reinforce its market position through affordable solutions. Identical concepts in the field of vehicle-based route information (digital map) will permit joint solutions. In the field of convoy formation and automatic, driverless operation, joint studies make sense when it comes to longitudinal guidance and vehicle protection.

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Strength Characteristics of Fe-SMA Reinforcement in RC Beam with Experimentation and Finite Element Modeling

Author(s): Priyanka Jadhav,Archana Gite,Rajan L. Wankhade / Language(s): English Issue: 3/2023

The work presented here aims at investigating the feasibility of iron-based Fe-SMA (shape memory alloy) reinforcement as an alternative to conventional steel reinforcement. The conventional steel reinforcement shows large plastic strain, low resistance to corrosion, low resistance to fatigue and also inadequate recentering capability. As a result, advanced materials available in the form of superelastic (SE) shape memory alloy (SMA) are fabricated to form structural reinforcements. This FE-SMA mitigates the problem of long- lasting deflection by using its reversible stress-strain capability. This iron- based Fe-SMA may be stimulated between the temperatures of 90 to 150°C, with which it is possible to strengthen the reinforced concrete (RC) beams without any crucial damage. The stress-strain behavior in tension, corrosion resistivity, pull-out tests of Fe-SMA reinforcement and flexural strength of RC beam were evaluated experimentally. The FE-SMA exhibits recovery stresses of 250-300 MPa subjected to a temperature of 160°C. A comparison of load-carrying capacity of iron-based Fe-SMA reinforcement is also shown.

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Wykorzystanie dronów w zakresie bezpieczeństwa. Nowe rozwiązania z projektu FASTER

Author(s): Przemysław Wrzosek / Language(s): English,Polish Issue: 1/2022

The expansion of technology in all fields of human activity is progressing.Undoubtedly, security is a sphere where new solutions and devices are much needed.For example, unmanned and controlled flying vehicles are already known and used bysecurity actors. However, thanks to the joint efforts of the scientific and research, tech-nical and security communities, novel solutions with a specific purpose of protectingpeople continue to be developed. Such an effort is the European project FASTER (“FirstResponder Advanced Technologies for Safe and EfficienT Emergency Response”), whichdeals with new technologies for rescuers at the scene of a crisis. Among other things,this project has developed new drone applications. These include drone swarming,active terrain mapping, distracting an attacker, searching for people and assistingrescuers (in various ways). Of particular importance is the optimisation of operations,made possible by the common operational picture (COP) system providing communica-tion and command of all technical and personnel resources of the rescue operation.

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Zaawansowane technologie zapewniające bezpieczeństwo i efektywność służb szybkiego reagowania

Author(s): Tomasz Łachacz,Fabio Perossini,Giuseppe Caracciolo,Anastasios Dimou / Language(s): English,Polish Issue: 1/2022

The aim of this article is to present the status of research conducted byan international consortium within the project “FASTER — First responder Advancedtechnologies for Safe and efficienT Emergency Response”, funded by the Horizon 2020programme. The analysis discusses the main objectives and assumptions of the projectand indicates technologies developed as part of the research. It also presents methodsfor testing the solutions developed by the consortium and lists pilots planned withinthe project.The conclusion draws attention to the possibility of using FASTER technol-ogy and system by first responders at the scene of a disaster

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THE CONDITIONS OF CHANGES IN RAILWAY TRANSPORT IN THE REGIONAL SYSTEM

Author(s): Adam Marcysiak / Language(s): English Issue: 132/2022

The subject of the study is to show the basic conditions of changes that are taking place on the rail transport market in Poland in the regional system. The statistical analysis was conducted by provinces. Significant regional differences in the use of railways as a means of transport are characteristic for Poland. Individual voivodships differ in terms of the parameters of the railway network, the manner and scope of its use, the density of railway lines, and the location of stations. Statistical analysis has shown that a high degree of economic and social activity of the population is conducive to better use of railways. There is also a feedback loop here. It is the railway that has had a positive impact on the growth of the region's GDP, counteracting social exclusion and unemployment.

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Technological Transition to Electric Aviation in the Kvarken Region: A Review of the FAIR Reports (Finding Innovations to Accelerate the Implementation of Electric Regional Aviation)

Author(s): Ejike Okonkwo / Language(s): English Issue: 1/2023

Accelerating technological transitions (TT) from carbon-based aviation to Electric Regional Aviation (ERA) is contingent on increased awareness and innovative ideas. Finding innovations to Accelerate the Implementation of Electric Regional Aviation (FAIR) aims to facilitate TT to electric aviation in the Kvarken-Nordland region of Finland, Sweden, and Norway. This paper reviewed 13 reports used in the FAIR project. These reports suggest that TT will provide many socioeconomic and environmental benefits. These include increased connectivity to new areas with zero operational carbon footprints, reduced cost, and travel time. However, most of the investigations in the FAIR reports focused on economic and technical aspects. Studies suggest that TT is also contingent on human factors such as public engagement and participation. Therefore, this paper notes that it is imperative to increase the knowledge of ERA among young people in higher educational institutions in the region, particularly given that they constitute an integral part of the aviation market. In addition, although the three universities participating in the FAIR project have energy-related studies, which are essential in advancing knowledge on TT, they lack aviation-specific courses. This paper proposes that, in their next agenda, regional actors could advocate for the introduction of a multidisciplinary aviation-centred course into the university curriculum. The idea is that such inclusion not only will increase the knowledge of ERA and the chances for accelerated innovative ideas in the implementation process but could also motivate and spur increased engagement in climate actions among young people.

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