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  • Mąka, Marcin; Majzner, Piotr (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The article proposes a model of the system supporting the decision-making process relating to the radio operator on board a ship after a distress alert is received by a Digital Selective Calling (DSC) controller working on VHF channel 70. The model is aimed at the implementation into the system of radiocommunication event management. The system takes into account the existing Radio Regulations. The model makes use of Petri nets, which are elements of graph theory. The time domain is comprised in the developed graph, and the states (places) and transitions capable of autonomous functioning are separated, as are those places and transitions requiring direct operator action based on empirical knowledge.
  • Wawruch, Ryszard (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    According to the International Maritime Organisation (IMO) recommendation, when the target data from the automatic identification system (AIS) and radar tracking are both available and the association criteria are fulfilled such that the AIS and radar information are considered for one physical target, then as a default condition of radar equipment, the AIS target symbol and the alphanumerical AIS target data, including information on the closest point of approach (CPA) and time needed to reach the CPA (TCPA) should be automatically selected and displayed as this is more accurate than radar tracking data as the current values of true and relative vectors of a manoeuvring object can be presented without time delay which is characteristic for radar tracking. Research conducted at sea on two ships using real navigational equipment has shown that sometimes onboard AIS presents CPA of other vessels equipped with this device as unstable and inaccurate as the automatic radar plotting aid (ARPA). The source of these instabilities and inaccuracies is to be discovered and thus implemented into radar-navigational simulators used for radar training at operational and management levels. This article briefly describes the encountered inaccuracy and instability of the values of the CPA of the encountered vessel presented by AIS, on current shipboard systems, and the possibilities of their demonstration on simulation devices.
  • Chybowski, Leszek; Gawdzińska, Katarzyna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Selected issues of component importance analysis for complex technical systems have been presented in this paper. A generic example of a complex technical system and selected statistics of operating losses have been described. A description and diagrams of both qualitative and quantitative importance analysis have also been included. The most significant problems facing complex technical system modelling have been pointed out. A multi-criteria system component importance analysis and the basic criteria for a system component quality evaluation have also been introduced. Some factors influencing the importance of the technical system’s components have also been described. Finally, the necessity of further developing importance analysis methods for machinery operation has been highlighted.
  • Ochin, Evgeny (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The idea of C/A codes GPS/GNSS Spoofing (Substitution), or the ability to mislead a satellite navigation receiver into establishing a position or time fix which is incorrect, has been gaining attention as spoofing has become more sophisticated. Various techniques have been proposed to detect if a receiver is being spoofed – with varying degrees of success and computational complexity. If the jammer signals are sufficiently plausible then the GNSS receiver may not realize it has been duped. There are various means of detecting spoofing activity and hence providing effective mitigation methods. In this paper, a novel signal processing method applicable to a single antenna handset receiver for spoofing detection has been described. Mathematical models and algorithms have been developed to solve the problems of satellite navigation safety. What has been considered in the paper is a spoofing detection algorithm based on the analysis of a civil satellite signal generated by mobile C/A GPS/GNSS single-antenna receivers. The work has also served to refine the civilian spoofing threat assessment by demonstrating the challenges involved in mounting a spoofing attack.
  • Sanecki, Józef; Klewski, Andrzej; Zygmunt, Marek; Stępień, Grzegorz; Hałaburda, Roman; Borczyk, Kamil (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents the problem of surveying landslide prone areas. Discussed are the possibility of using photogrammetry methods for digital imaging, creating Digital Terrain Models (DTM) and Digital Elevation Models (DEM) of slope surface and combining these with the ground’s angle of internal friction, cohesion and hydrogeological data. Unmanned Aerial Systems (UASs) with inclined high precision cameras show different slope angles than UASs with vertical cameras. Expressly, we can see places within the landslide area where the angle of internal friction and cohesion are low. These places are the most likely to suffer further mass movements causing fissures and ground displacements. In the observed landslide area we separated the steep parts of the slope, with low cohesion values, and the slight parts of the slope, with low values of angle of internal friction. In these different areas, landslides can evolve in different ways and at different speeds. The Factor of Safety (FS) was calculated for different types of area which allowed the probability of new mass movements to be checked for different areas. This method can be useful for C-B and X-Band PSI Interferometry Data. Because of the damage potentially incurred by landslides, there is a need to better understand these natural phenomena, especially their methods and speed of development and how they can be prevented from forming in the future.
  • Wawrzyński, Wojciech (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper deals with the susceptibility of the roll equation to the bifurcation phenomenon depending on the damping coefficient value and form of the roll damping formula. Generally, the bifurcation phenomenon depends mainly on the shape of the righting arm curve (GZ curve), but roll damping also has a significant impact. The commonly used formulas for roll damping are presented, as well as values of the linear equivalent roll damping coefficient, calculated according to the simple Ikeda method. Values of the linear equivalent roll damping coefficient were calculated for a wide spectrum of roll amplitudes and roll frequencies for two ships. The loading conditions for these ships were selected to show different GZ curve characteristics. One ship has a softening spring characteristic and the second has a hardening spring characteristic. For these two ships, a number of calculations of roll spectra are presented where the bifurcation phenomenon occurs. Calculations were made for different damping coefficient values and forms of the roll damping formula.
  • Pilawski, Tadeusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Zwiększająca się z roku na rok pula nawozów mineralnych dostarczanych przez przemysł naszemu rolnictwu oraz wzrost mechanizacji rolnictwa, doprowadziły do wzrostu plonów czterech podstawowych zbóż z 19,2 q/ha w roku 1965 do 21,6 q/ha w roku 1969. W latach 1970 -85 przewidywany jest dalszy wzrost plonów do 27,5 q/ha. Z punktu widzenia potrzeb gospodarki narodowej, narasta więc bardzo ważny problem zwiększenia pojemności magazynowych w celu należytego zabezpieczenia i przechowywania dostarczanych przez rolnictwo mas ziarna. Obecne zaplecze magazynowe nie jest wystarczające dla masy zbóż wymagającej odpowiedniego przechowywania. Zwiększenie produkcji w najbliższych 15 latach będzie wymagać znacznych powierzchni magazynowych, a planowana budowa nowych magazynów nie pokryje całkowicie deficytu. Jednym ze środków poprawy tej sytuacji może być zwiększenie pojemności magazynowych przez przystosowanie statków wycofanych z eksploatacji morskiej na zbożowe magazyny pływające w portach Szczecin, Gdańsk, Gdynia i Kołobrzeg.
  • Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    It is my great pleasure to introduce the latest issue of the Scientific Journals of the Maritime University of Szczecin number 51 (123). Taking advantage of this opportunity, I would like to share with you some news about the journal. Scientific Journals of the Maritime University of Szczecin have set sail to wide international waters thanks to the Web of Science Core Collection – a database in which they have been indexed since July this year. Until 2014, articles published on the pages of the Scientific Journals of the Maritime University of Szczecin (SJ) were indexed in bibliometric databases such as BazTech, EBSCO, Google Scholar and Index Copernicus. In recent months, the journal has been registered in new bases (Chybowski, 2016b), which resulted from the inclusion of SJ in the Emerging Sources Citation Index (ESCI) last October. This database is a part of the prestigious Web of Science platform (Chybowski, 2016a). A calendar of the major events related to the activities of SJ, from January 2015 is shown in Table 1.
  • Souchkov, Valeri (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Over the past decades, demand for innovation in diverse industries, including the maritime industry, has been steadily growing. One of the primary sources of innovation has been the finding of inventive solutions to the most challenging problems. Until recently, the search for inventive ideas relied heavily on random and chaotic methods of boosting creative capabilities, thus drastically reducing productivity in the generation of new concepts and solutions. With the emergence of systematic methods for generating inventive solutions, the situation has changed. Modern methods such as TRIZ suggest a process of solving problems in a systematic way whereby each phase of the process is supported by the relevant analytical techniques and heuristic tools. This article presents Root Conflict Analysis (RCA+), a technique for problem analysis developed for the top-down decomposition of problems to chains of causes and contradictions. The article provides an example of applying RCA+ to discover the causes and contradictions which led a ferry to lose stability at sea.
  • Bistrović, Miroslav; Ristov, Pančo (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Although various methods of using new techniques and technologies in ship fire alarm systems have been developed to date, some of which have made significant improvements in the functioning of such systems, in practice there is still plenty of room for further research regarding the operational efficiency of ship fire alarm systems and its impact on crew, passenger and overall ship safety. The application of electronic and computer technologies enables the development of intelligent solutions to improve the efficiency of ship fire alarm systems. Besides the economic justification, this paper presents a comparative analysis of classical and modern approaches based on video detection and computer vision in the detection of early phase smoke as a precursor to fire incidents. The economic justification of the new approach is concerned with decreasing the costs incurred by the untimely detection of the early stages of fire in ship engine rooms.
  • Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The Miniature Dwarfs method is one of the tools used by the Theory of Inventive Problem Solving (TRIZ) used in the process of modelling and seeking solutions to conflicting situations. This article describes the origin of the Miniature Dwarfs method. The process flow of the usage of the Miniature Dwarfs method was presented both in its original version, suggested by Altshuller, as well as in its recently modified version. The usage of the Miniature Dwarfs method was presented here to minimize the marine hull resistance of a passenger ship in the conflicting situation, where there is a simultaneous necessity to provide both large ship capacity as well as high speed. The issue and the conflicting situation were both presented and modelled. The Operational zone and Operational time were described and modelled with the use of the Miniature Dwarfs method before and during the Conflict, and the desired situation. The search of the potential solutions was carried out with the use of miniature dwarfs; the findings were interpreted with respect to the system under analysis and the stated technical issues. Imagined situations described in individual diagrams are included in the issue under investigation. Selected solutions to the problem were presented. The advantages of the method were indicated and presented as an addition to other methods used in the process of designing new engineering solutions.
  • Nourghasemi, Hadi; Bakhtiari, Mohammad; Ghassemi, Hassan (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    One of the most effective methods to diminish the drag of a planing craft is to use a step at the bottom of the hull. A stepped hull causes a reduction of the wetted area and, as a result, a decrease in the drag. The step may be designed as a straight line through the entire width of the hull or may be V-shaped with a forward or backward swept angle. In this paper, the effects of the step forward swept angle on the hydrodynamic performance of a hard chine planing vessel are investigated by finite volume method (FVM). Reynolds-Averaged Navier Stokes (RANS) equations with a standard k-ε turbulence model coupled with volume of fluid (VOF) equations are solved in order to simulate a transient turbulent free surface flow around the hull with the help of Ansys CFX software. In order to predict hull motions, equations of rigid body motions for two degrees of freedom (2-DOF) are coupled with fluid flow governing equations. To validate the presented numerical model, first the numerical results are compared with available experimental data, and then the obtained numerical results of the drag, dynamic trim, sinkage, wetted keel length, wetted chine length, pressure distribution on the hull, wetted surface and wake profile at different Froude numbers and step angles are presented and discussed.
  • Mielniczuk, Sylwia (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Various methods of trajectory determination are used for finding solutions to collision situations involving ships. This applies to avoiding collisions with other ships or stationary objects. In addition to the methods generally used, new or modified versions of methods derived from other modes of transport are proposed. One of the algorithms for route determination serving to avoid obstructions is the method of artificial potential fields, used for determining routes of mobile robots. The method is used in maritime transport, for instance for detecting anomalies in ship movement. The article presents the method of potential fields used for solving the problem of route selection avoiding navigational dangers and obstacles. This article presents an algorithm of route determination based on the said method, its implementation in the MATLAB program and examples of application for the ship’s safe trajectory determination in some navigational situations.
  • Szymankiewicz, Dariusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Implementation of ERIKA III, the third package of EU legislation intended to integrate international standards of marine accident investigation, has significantly changed the way Polish public authorities investigate marine accidents. Until the implementation, maritime chambers conducted the investigation of marine accidents. Since October 2012 there has been a dual system in place whereby public authorities are entitled to investigate marine accidents in Poland. This article reviews distinctive features of both approaches and the impact thereof on the system of investigating marine accidents. Beside a theoretical description of the legal basis for the functioning of both maritime chambers and the State Marine Accident Investigation Commission, this paper includes analytic data of investigations conducted by both these bodies in order to prove that the number of investigations conducted by maritime chambers has drastically decreased since the establishment of the State Commission, and that the number of investigations conducted by the State Commission itself cannot be sufficient, leading to a decrease of safety in maritime navigation.
  • Chybowski, Leszek; Gawdzińska, Katarzyna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The paper presents the application of cost-based, component-importance measures for complex technical systems. A stern tube sealing system installed on a sea vessel was used as an example of a complex technical system. Selected statistics of a ship’s operation losses were calculated. Selected, known-importance measures were presented and the authors’ own approach to cost-based, component-importance analysis was shown. The following measures were discussed: the operation-interruption cost index, the maintenance potential, the simulation- based maintenance index, and maintenance and operational costs. A description of factors influencing the importance of the technical system components was provided.

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