Logistics and Transport (E-Journal)
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FACTOR ANALYSIS AS A MEANS OF FILTERING RAMS INDICATORS FOR RAILWAY VEHICLES
Get PDFEuropean Commission Regulation (EU) No. 445/2011 regarding the system of certification for entities in charge of maintenance (ECM) of freight wagons requires such entities to supervise the condition of wagons, without specifying the methods of supervision to be used. Each ECM should establish a Maintenance Management System (MMS), which will include the obligation to monitor the fleet of freight wagons. Monitoring railway vehicle maintenance operations should include tracking all significant technical and operational indicators. The key question is which indicators are the have the greatest impact on safety. This paper discusses some issues related to the monitoring of maintenance operations for railway vehicles. It also looks at dedicated solutions for entities in charge of the maintenance for freight wagons based on PN-EN 50126:2002 standard and RAMS indicators (Reliability, Availability, Maintainability and Safety). This paper describes factor analysis of the proposed indicators as a means of selecting those that have a decisive impact on the correctness of the process for monitoring vehicles. This paper shows an example of the implementation of the requirements of the European Commission Regulation 445/2011 [3] regarding the monitoring of the state of railway vehicles and the possibility of using the information so gained as part of a process of continuous improvement. Reducing the number of indicators will reduce the amount of data needed to calculate all the RAMS indicators, without compromising the benefits of the rail vehicle monitoring system.
Theoretical Approaches for Safety Levels Measurements – Sequential Probability Ratio Test (SPRT)
Get PDFIncreasing of civil aviation safety level is one of principal objectives of world air transport development. Present research paper discusses new theoretical approaches to searchingfor methods to assessthe “safety space” of civil aviation activity. Special attention is paid to an effective test, proposed by A. Wald
Historic Railway Spans Modernization with the Use of Modern Slab Track Surfaces, on the Example of the Wroclaw Główny – Wroclaw Main Railway Station Reconstruction
Get PDFModernization or revitalization of a railway line involves the necessity of reconstruction or renovation of practically all the engineering objects and constructions on its premises. While, in the case of objects, not protected by the Historic Preservation Maintenance of City-Owned Buildings, the situation is relatively easy, in the case of historical buildings, the scope of possible construction works can be significantly reduced.On the example of the modernization of the Wrocław Główny railway station track system, the use of modern slab track is presented, whose aim is to obtain the required performance parameters of the engineering structures (old boreholes) located in its area. The non-skid surfaces used are ERS - rails in the cover and block rails of the EBS type. The use of pavement-free pavements allowed the historic bays to be preserved. Their main girders are made of riveted baffles, without interfering with their historical material.The presented solutions can also be used for the modernization of different types of engineering objects and construction, not necessarily recorded in the register or records of historical monuments - for example, in riveted constructions of those of or unique shape, located on lower category railway lines. It gives opportunity to preserve and continue to use old objects, exposing their beauty and technology, currently not used (for example riveting)
Possibilities for Using NoSQL Databases in Information Systems in Transport
Get PDFThe article presents directions for development of end-user-oriented information systems in transport. Characteristics of databases belonging to the trend of NoSQL have been enumerated as well as the represented data models.The example of a relational model transformation to a graph form and the concept of application of a graph database for connections search in public transport system have been presented. The general concept of a distributed information system has been presented which uses NoSQL databases in particular modules
Rehabilitation of Prestressed Concrete Bridges by FRP Composites in the Light of in Situ Testing
Get PDFThe article presents the analysis of FRP composite materials strengthening systems for pre-stressed bridge structure elements. Displacements and strains of main beams of bridges were investigated before and after the strengthening executed by FRP composite materials. Test load field and theoretical analysis were performed after bridge structure repair. The results of bridge structures after strengthening in field load tests allowed for an assessment of theefficiency of the strengthening, as well as establishment of guidelines for future reference concerning this type of maintenance in the engineering practice
The Reorganization of the Traffic in the city of Opole during the Renovation of Niemodliński Bridge
Get PDFIn the near future the city of Opole, as well as the whole Opole Voivodship are going to suffer from a serious problem connected with the traffic system which provides for closing of the core bridge crossing from one part of the city to another one – the Ulga canal. The condition of the bridge crossing at Niemodlińska Street is constantly deteriorating. After the first expertise had been conducted by a construction supervision, the decision to close the bridge on 1st June 2015 was made. The decision is justified by the safety reasons and disastrous technical state of the bridge crossing. In order to delay the moment of the closing and lighten the bridge, the inside lanes were changed into bus lanes and thereby the centre of gravity has been moved closer to the bridge crossing axis. Cars are going to use outside lanes. In front of the bridge vehicles height limiters were set in order to eliminate trucks from the traffic. For this kind of vehicles a special detour was created (Wrocławska Street, Road No 45). After this procedure the next expertise of construction supervision was conducted whereby the exclusion of the bridge from the traffic was delayed for one year. For the time being, it is known that the third expertise is being prepared. During the bridge renovation the car drivers and public transport passengers who travel to work every day are going to come across the serious communication problem
Parametric Assessment of Competitiveness of Commercial Sea Ports Based on Their Logistic Potential with the Use of the AHP Method
Get PDFThe article comes as a summary presenting one of the stages in the realisation of a project carried out at the Chair of Logistics at Gdańsk School of Banking (WSB Gdańsk) in the cooperation with Fachschule in Stralsund. The project concerns the use of multi-criteria decision models for assessing competitiveness of commercial sea ports based on their logistic potential. The project team, whose members have a lot of experience in the field of sea logistics gained during their long professional practice, has verified a preliminary concept representing a logistic model of a commercial sea port. The project team has also provided the analysis of the use of multi-criteria decision models for the assessment of the suggested model, in terms of the competitiveness of the analysed entities. The suggested model of the logistic potential of a commercial sea port is graphically interpreted and described with the use of a multi- criteria assessment sheet. It refers strictly to the factors which determine the macro-, micro-, and mezzo-economic levels of competitiveness presented by such an economic entity as a commercial sea port. The logistic potential of a commercial sea port is presented as a hierarchical set of criteria, sub-criteria and diagnostic features assessed at the level of the analysed installation, which is directly compared with other competitive installations. During the research and in the course of analyses, it has been decided that further assessment shall be performed with the use of the following method: the analytic hierarchy process of decision making. This method comes as an optimal instrument to provide mutual assessment of logistic potentials of the analysed entities which operate in particular sea areas. An adequate methodology has been also selected to comply with the suggested solution – it allows the authors to quantify the logistic potential of a commercial sea port in terms of its competitiveness
Accessibility to Passenger Rail Transport in the Łódź Province
Get PDFThis article presents results of research devoted to spatial diversification of accessibility to passenger rail transport in the Łódź province. The analysis was conducted on the basis of a full inventory of railway connections of carriers providing their services within the boundaries of the region. Calculations were made in reference to 158 train stations and train stops as well as the population of 4,965 settlement units. Two variants of reaching a train stop by passenger were distinguished: on foot and using individual car transport. Both solutions include a number of border variants in the form of maximum equidistances of access on foot and isochrones of travel by car. Research proceedings were based on two-step floating catchment area (modified for the purposes of research into effectiveness of public rail transport), which provides for train frequency and travel time to individual stops from the topological perspective
Process Variation and the Total Productive Maintenance. Case Study in the Manufacturing Plant
Get PDFOne of the concepts decreasing the variability of the production processes is the Total Productive Maintenance. The aim of the article is to examine the impact of the TPM implementation on the reduction of process variation on the example of the production company. In the first part of the paper a short literature review in the context of the variability of processes and the characteristics of the TPM concept has been performed. Also a way ofimplementation of the concept in the production company has been presented. The second part contains the description of the applied research tools, it also presents research results and shows the final conclusions regarding the impact of TPM on the process variation in the studied company