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  • Javanmardi, Mohammadreza; Binns, Jonathan; Izham, Muhammad Iqbal Che; Rafieshahraki, Jalal (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The presented work is an experimental investigation into the waves generated by a pressure source moving in a straight channel. Wave fields generated by the moving pressure source are described and the effects of angle of attack on the generated wave height, surfable wave quality, drag and vertical forces are presented. The main objective of this study was to investigate the relationship between the angle of attack and the generated wave height across the towing tank width and the surfable wave quality. The investigations were conducted at the Australian Maritime College towing tank on a wavedozer at four different attack angles at various speeds. Three wave probes were installed across the channel to record the generated wave heights. Based on the experimental results, it was concluded that smaller angles of attack produced higher quality surfable waves compared to larger angles of attack, while the height of the generated wave has a direct relationship with the angle of attack. By comparing the forces for different models, it was concluded that the pressure source with the lowest angle of attack has the minimum drag but maximum displacement.
  • Kijewska, Monika (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In this paper, the route prediction for a person in water was performed on the basis of a developed graph algorithm. This person drifted in water under the influence of surface currents and wind. The total drift route for the person in water was established as the route in a weighted directed graph. Vertices of this graph correspond to given points within a given basin. Additionally, the graph’s edges show possible directions of the overall human drift. The weight of the given edge describes the difference between the gradient of the edge and the total drift direction calculated on the basis of surface current field data and wind field data. An application has been created on the basis of a given algorithm which might be used to support the search for survivors in coastal areas (e.g. port basins, basins adjacent to the port, bays and sea areas) for which hydrodynamic models reliably reflect local phenomena.
  • Mąka, Marcin; Majzner, Piotr; Lisaj, Andrzej (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents the structure of a model of the allocation of radiocommunication events at coastal radio stations, land-based satellite stations and on vessels in sea area A3. The propagation of radio waves in the HF band has been analyzed to examine the range of various radio stations and their capabilities of establishing communication between each other. We also present methods of modeling and displaying the deployment of individual stations, of presenting radiocommunication events as a function of time using time diagrams, as well as the manner of the chronological presentation of radiocommunication events and related decisions. It has been shown that there is a relationship between the effectiveness of communication and propagation conditions that is strongly dependent on the time-of-day. We present the need to develop a decision support system for the radio operator on the bridge.
  • Ochin, Evgeny (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    One of the main problems in modern navigation of both manned and unmanned transport systems is that of transport safety. Differential GNSS technology has been used to improve the accuracy of transport positioning, in which position is calculated relative to a fixed reference station with a known position XYZ. Unfortunately, GNSS is vulnerable to malicious intrusion. GNSS signals and/or correction signals from the reference station can be spoofed by false signals, and special receivers have been used to provide defenses against such attacks. But how can the roving receiver (i.e. the user) be sure that the information they receive is authentic? Spoofing is the transmission of a matched-GNSS-signal-structure and/or signals to a reference station in order to cause interference and attempt to commandeer the tracking loops of a victim receiver, thereby allowing manipulation of the receiver’s timing or navigation solution. A spoofer can transmit its counterfeit signals from a stand-off distance of several hundred meters, or it can be co-located with its victim. In this article we consider the principles of spoofing detection using Differential GNSS, in which a correction signal from the reference station is used for the detection of spoofing
  • Przywarty, Marcin; Dzwonkowski, Jan (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents preliminary results of research to develop a method of analysis of chosen parameters of vessel traffic flows on a bend in a waterway. Assumptions within the model are based on the geometrical dependences and, for a significant part, on expert experience and real life manoeuvring tactics. The work is focused on the analysis of coordinates of a ship, reduced to its centre of gravity, for different input and assumed output parameters. The proposed method allows also for the analysis of other parameters that influence navigational safety such as rate of turn. The results confirm the possibility of assessment of traffic flow parameters with use of the developed method. In the next stages of the work, algorithms which are capable of accounting for human factors and external conditions can be implemented.
  • Dobryakova, Larisa; Lemieszewski, Łukasz; Ochin, Evgeny (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Spoofing, anti-spoofing, jamming and anti-jamming technologies have become an important research topic within the GNSS discipline. While many GNSS receivers leave a large space for signal dynamics, enough power space is left for the GNSS signals to be spoofed and/or jammed. The goal of spoofing is to provide the receiver with a misleading signal, fooling the receiver into using fake signals in the extra space for positioning calculations. The receiver will then generate a false position, thus misleading the navigator. The goal of jamming is to add noise to the satellite signal which leads to fooling the receiver into using “signals plus noise” for positioning calculations. This article discusses the approach to anti-jamming based on the shielding of antennas from the signal jammer.
  • Galor, Wiesław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In many cases, sea ships are required to call at ports situated several hundred kilometers inland, including several different types of ship (freight, passenger, recreational). The main benefit of sea-river navigation is that ships may enter inland and carry cargo to the ports of other countries without their cargo having to be transferred several times. This method significantly reduces the risk of damage to the cargo and also lowers transport costs. An important element in sea-river shipping which is showing an increasing trend is that of passenger shipping (cruisers). This article analyzes the current situation of this type of navigation in Poland. Several examples of shipping routes on inland waters are presented.
  • Slišković, Merica; Hadžić, Ana Perić; Vukić, Luka (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper analyzes the external environmental costs and revenues of cruise traffic in the port of Split in 2015. In order to explore the perspectives of increasing the current mode of cruise traffic in the future, results were compared with those previously known for the port of Venice. The use of the same research methodology was an important condition for this comparison. The cruise tourism business has a negative balance sheet when comparing the costs and revenues in both cities: the external costs are higher than the revenues. Growing cruise traffic leads to further growth of the external costs, deepening the negative cost-benefit ratio. Valorization of damage is a sensitive topic which conflicts with the interests of various parties but is also an important factor in the apparent unsustainability of the current mode of cruise tourism. The authors want to highlight the similar problems of the two cities and encourage the authorities to implement the necessary controls to limit such damage.
  • Wilhelm, Johannes; Ptak, Mariusz; Rusiński, Eugeniusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The performance of passive safety devices to protect vulnerable road users, or otherwise endangered persons, from severe injuries in cases of impacts and accidents has improved notably in recent decades. The devices’ levels of performance appear to have plateaued but the numbers of severe injuries and deaths caused in such incidents could be decreased further if new solutions are found. At first, the possibilities for improving the impact behavior of passive safety devices may appear to be restricted to device geometry; however, it is in fact also possible to rethink the applied materials and to utilize natural principles in their design. In this study, impact related brain injury mechanisms and injury criteria are investigated using dynamic simulations and Finite Element Head Models, results from which are compared with data collected from real-life accidents. As these tools are advancing considerably in terms of accuracy, information density and complexity, they provide, like expert knowledge from the fields of biomechanics, biomedicine and neuroscience, valuable input for further development.
  • Włodarczyk-Sielicka, Marta; Bodus-Olkowska, Izabela (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Mobile navigation for inland shipping is an example of a GIS system dedicated for recreational users using inland waterways. Developing this system is a primary purpose of the research project “Mobile Navigation for Inland Waters” funded by the National Centre for Research and Development under the program LIDER. System assumptions include the development of a dedicated model of mobile cartographic presentation, taking into account the generalization of data. This article is focused on simplification of line and polygon features, included in the spatial data model MODEF (MObinav Data Exchange Format), which is used in the created system. During the simplification of line features, the Douglas-Peucker algorithm was mainly implemented. During the simplification of polygon features, a simplification method was applied, maintaining the basic shape and size of the objects. A simplification tolerance parameter and a parameter determining the minimum area of the object was also used. In addition, objects within a certain distance were merged. A smoothing tool for the shape and size of buildings and the PEAK method (Polynomial Approximation with Exponential Kernel) were used as well. Furthermore, a selection tool was employed and features with minor importance to the user were deleted during navigation mode. Given the requirements of the future user of the system, a separate model simplification for each of the layers of the system was created; these models are combinations of the methods listed above. The overriding factor that has been taken into account during the research of simplification methods, was the limitation of the sharpness of human eyes. The study of generalization methods was carried out in ArcGIS software.
  • Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dear Readers, It is my great pleasure to present to you the 49th issue of the Scientific Journals of the Maritime University of Szczecin. This issue contains the most current research findings from the fields of marine engineering, sea navigation and transport engineering. We have also included papers discussing the issue of mining safety, the use of new communication techniques as well as data mining models to predict ocean wave energy flux in the absence of wave recordings. The introductory article for this issue has been prepared by Professor Oliver Mayer, Senior Principal Engineer at General Electric Global Research. The article is devoted to the concept of using TRIZ (Theory of Inventive Problems Solving) tools, especially the innovative application of trimming for rationalising electrical networks. Its publication has been financed by the Polish Ministry of Science and Higher Education from a fund dedicated to the promotion of science. It is our expectation that this resource will be both interesting and useful for those searching for state-of-the-art methods of developing technical systems. The Marine Technology and Innovation section features articles on marine hydromechanics, dual-fuel engines, and selected aspects of vessel automation. The Navigation section contains articles on a mobile navigation system, concepts related to the intact stability of a bulk carrier, and control procedures for merchant vessel course indicators. The Transportation Engineering section contains articles on inland transportation, and experimental verification of the concept of using controlled pyrotechnic reactions as a source of energy as a part of the transport system from the seabed. We strongly encourage authors to submit their articles, and readers are more than welcome to forward their remarks. To access an online version of the current issue as well as archival volumes, please visit our website http://scientific-journals.eu/. Leszek Chybowski, DSc PhD CRP Editor-in-Chief
  • Mayer, Oliver (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    TRIZ trends predict an increased electrification of engineering systems. One of the visible effects of this is lighting, in this case party lights on boats. The need to furnish a boat with colorful illumination requires a flexible, redispatchable system. Cable-bound illumination does not meet this requirement. A solution is presented in this paper using TRIZ as a problem-solving methodology. TRIZ comprises a set of heuristic tools for problem analysis, reformulation, root cause analysis, and problem-solving algorithms. TRIZ, however, concentrates on generating solutions to problems irrespective of given limitations concerning, for example, safety, producibility, or cost. TRIZ provides a direction of thinking that has been proven successful in the past for similar problems. Other tools must, nevertheless, be used to carry out a technical evaluation of the feasibility of the solution, scalability, practicability, or cost target. TRIZ tools are widely used by engineers in multinational corporations such as Intel, GE, Philips, Siemens, Bosch, Boeing, Samsung, LG, and Cochlear. In this paper, selected tools from the overall TRIZ toolbox will be used and explained, with a focus on functional analysis, trimming, and resources. However, other aspects (Trends, Function Oriented Search (FOS), and Ideal Final Result (IFR)) will also be presented.
  • Abramowski, Tomasz; Sugalski, Karol (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents the general method for hull shape optimization of fishing boats with the objective of reducing resistance. In particular, it presents an example of the results of the application of resistance-reducing devices such as the ducktail, the cylindrical bulb and the streamlined bulbous bow. The resistance was determined using computational fluid dynamics (CFD). For the purpose of flow simulation, the OpenFoam system, distributed under an open source license, was used. The turbulent, unsteady flow with free surface liquid around the analyzed hulls was computed and investigated for potential resistance reduction. Ultimately, the calculation results were generalized by the parameterization of dimensionless geometric variables for the shape of a bulbous bow and were given in a form suitable for practical application in the hull design process.
  • Chłopińska, Ewelina (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents an alternative solution for marine units operating both inside and outside areas covered by strict controls on sulphur emissions. Emission Control Areas include the waters of the Baltic Sea, the North Sea, the English Channel, and the coasts of North America. Shipping in these areas is obliged to use fuel with a sulphur content in accordance with European Parliament and Council Directive 2012/33/EU. The technology to power units with marine diesel oil and other fuels compliant with the requirements of the Sulphur Directive is described. Low-sulphur fuel is efficient and environmentally friendly, and liquefied natural gas (LNG fuel) is an example of the technology described.
  • Kaszycki, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dynamic development in Programmable Logic Controller (PLC) technology has brought about the common use of this equipment in industrial systems of automation and measurement. One popular PLC group creates MICRO class controllers which are cheap but offer many possibilities. In most cases, these controllers are equipped with binary inputs and outputs only. For this reason, their use in analogue control and measurement systems causes certain difficulties. The current paper describes the adaptation of PLC MICRO class controllers with a binary system of inputs and outputs for use in analogue control and measurement systems by the implementation of pseudo-analogue input and pulse-width modulation (PWM)-type output. The current paper presents a detailed design of this type of adaptation for PLC SIMATIC S-7 CPU 222. A practical system was designed, built and tested in the laboratory. The results of tests for pseudo-analogue input and PWM-type output are included in graphic form. The limitations of the proposed solution and its areas of applicability in ship automation are presented.

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