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  • Lushnikov, Evgeny M. (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2012)
    In the paper the priority of technical means and methods of navigation at contemporary seagoing ship was discussed. The role of magnetically compass and gyrocompass at the condition of contemporary ship was described. Effectiveness of gyrocompass and magnetically compass from point of navigation and economy was analyzed. The result of analysis is reflected at the recommendation for navigators and managers of ship’s company
  • Lushnikov, Evgeny M. (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2010)
    The method of high accuracy for dynamically tuned gyroscope is presented. The mathematical description and calculation of the gyroscope‟s parameters which have coefficient of integrating 6.9 are described. The characteristics of the resonance depending of generalized parameter and influence of balance variation on accuracy were analyzed. The result of experiment is according to theory at condition of experiment in vacuum chamber
  • Pleskacz, Krzysztof; Lushnikov, Evgeny M (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2012)
    The article presents a method to determine the gyro correction by utilizing parallel lines used in radar, taking into account the advantages of this method, which are the convenience and ease of use. The accuracy of the method according to the geographical and technical factors was analyzed. The mathematical calculation of the final results accuracy was presented. Situations in which it is recommended to use this method for determining gyrocompass corrections due to the high accuracy were describe
  • Raev, M.; Skvortsov, E.I.; Kravtsov, Yu.A (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2012)
    New two-stage method for observation and processing of radar signals and images is suggested, which uses two-polarization X-band radar and significantly improve accuracy of sea surface current velocity measurement
  • Lushnikov, Evgeny M. (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2012)
    The problem of routine control of true courses from gyrocompass and from magnetic compass is presented. It is shown, that contemporary method of monitoring is not agree to science methods and is not agree to the intention of navigation safety. The reasons of this situation in aspect of history are analysed. The role of education at solution of this problem is exhibited. The problem is analysed at technical aspect, low aspect, moral aspect. The methods and means of resolving of the problem are presente
  • Pleskacz, Krzysztof; Lushnikov, Evgeny M (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2012)
    The article presents a method to determine the gyro correction by utilizing parallel lines used in radar, taking into account the advantages of this method, which are the convenience and ease of use. The accuracy of the method according to the geographical and technical factors was analyzed. The mathematical calculation of the final results accuracy was presented. Situations in which it is recommended to use this method for determining gyrocompass corrections due to the high accuracy were describe
  • Filipowicz, Włodzimierz (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2013)
    In traditional approach to position fixing navigator exploits mathematical apparatus based on probability theory. Series of assumptions are required in order to use the platform to draw final conclusions. Limited ability is available regarding fix accuracy a posteriori evaluation. In the paper Mathematical Theory of Evidence is exploited in order to introduce new foundations enabling modeling and solving problems with uncertainty. Modified scheme of approach towards making the fix delivers new standpoint for perceiving accuracy of the result
  • Lushnikov, Evgeny M.; Pleskacz, Krzysztof (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2013)
    The article presents the results of compliance with effects of impact wave course and the resulting orbital motions on the accuracy of the gyrocompass.
  • Praczyk, Tomasz; Szymak, Piotr; Milewski, Stanisław (Scientific Journals of the Maritime University of Szczecin, Zeszyty Naukowe Akademii Morskiej w Szczecinie, 2013)
    The article deals with the problem of variability of spatial orientation and the position of the ship gun in time and the impact of this variability on the gun accuracy. In the paper three approaches to this problem are presented. Moreover, the conception of research is presented, which is aimed at verifying each of the approaches and selecting the solution that will guarantee the highest effectiveness of the gun.
  • Burzyński, Andrzej (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In his article the author analyses the accuracy of objects which are situated on the sea. Research on selected objects has been carried out in the Vessel Traffic Service cov-ering the Gulf of Gdansk. The author compares positions of those objects on the basis of VTS and DGPS readings.
  • Nowak, Aleksander; Wąż, Mariusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper describes problems connected with navigation satellite systems accuracy in urban areas. We considered the influence of reflected signals and changes of space segment geometry caused by radio shadow effect. All analyzed data were obtained thanks to authors’ simulation software
  • Dziełak, Ewa; Jóźwicki, Paweł (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article includes a mathematical description of calculating the accuracy of movement parameters of an encountered vessel and a comparison of required accuracy specified in IMO resolutions and theoretical calculations.
  • Łusznikow, Eugeniusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In article the question of accuracy increase for radar-tracking observations is con-sidered by transition to diverse differential lines of position – to isogons and hyperboles. The simple technique of construction of such lines of position is offered. The mathemati-cal description for an estimation of casual errors of a method is resulted; mathematical expression for calculation of a gradient direction of an isogons is resulted.
  • Felski, Andrzej (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Many radio-navigation systems dating from the seventies and eighties of the last century were replaced by a single Global Positioning System (GPS) a dozen or so years ago. However, for several years the opinion that the GPS monopoly is becoming dangerous has been expressed increasingly often in navigational literature. Even when supplemented with other systems from this group, such as Global Navigational Satellite Systems (GNSS), it cannot be treated as the source of reliable and universally accessible navigational information. This results from the similar sensibility of all GNSS systems to the same disturbances as a consequence of using a similar band of radiofrequencies and a similarly low powered signal. There is a growing recognition in the maritime world that GNSS will not provide the resilience required because of these common vulnerabilities. The World Wide Radio Navigation System should be seen as a combination of systems, which can cooperate and work effectively even when GNSS does not work. Lately different authors commonly point-out the potential advantages of a modified Loran (e-Loran), however it still remains only a potential option – particularly in the southern hemisphere, where this system has never existed. Meanwhile as the general threat of the disturbance of GNSS systems increases, the matter of initiating alternative possibilities becomes more urgent. A proposal which combines lower financial outlays with adjustments to the existing techniques and the law in force is desirable. In this context radar seems to be the attractive option, however for utilization as an alternative to GNSS it should reach considerably higher technical performances. In the paper the general limitations in the use of existing radar as a means of ships’ positioning are presented, and information published about the investigation into the methods for overcoming these limitations is discussed. The accessible information appears to prove that a greater accuracy of position can be achieved with modified radar in the future, especially if the suitable navigational infrastructure is present on shore. However, the level of accuracy of this method does not seem to compare favorably with GNSS.
  • Lushnikov, Evgeny; Pleskacz, Krzysztof (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article examines the current state of practices concerning the monitoring of the accuracy and reliability of compasses on modern ships in the global fleet. The author analyzes personally detected, bizarre, but commonly used practices that may indirectly lead to hazards to human life, and impose a serious risk of marine environmental pollution. The author indicates probable reasons for the present state, and proposes directions, resources and methods for rectifying the situation. The problems presented, which represent the results of a broad study, call for decisive solutions in such areas as technology, education, law, and morality.
  • Kulbej, Eric (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Position determination of Global Navigation Satellite Systems (GNSS) depends on the stability and accuracy of the measured time. However, since satellite vehicles (SVs) travel at velocities significantly larger than the receivers and, more importantly, the electromagnetic impulses propagate through changing gravitational poten- tials, enormous errors stemming from relativity-based clock offsets would cause a position error of about 11 km to be accumulated after one day. Based on the premise of the constancy of light, two major relativistic effects are described: time dilation and gravitational-frequency shift. Following the individual interests of the author, formulas of both are scrupulously derived from general- and special-relativity theory principles; moreover, in the penultimate section, the equations are used to calculate the author’s own numerical values of the studied parameters for various GNSSs and one Land Navigation Satellite System (LNSS).
  • 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.
  • Weintrit, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Navigational charts are a basic source of information for seafarers. But how accurate and reliable are they? How much trust and confidence can be put in them? Unfortunately, the answer is not so simple; it is far more complicated than merely saying that one chart is accurate and reliable while another is not. However, any seafarer navigating in unfamiliar waters should have the necessary skills. It is a great challenge – some may say an impossibility – to keep the thousands of navigational charts up to date. But exactly how out of date, how inaccurate, are the chart data? Chart users will have a better idea now that the Hydrographic Office is gradually implementing a new chart feature called the Zone of Confidence (ZOC) box which replaces the Source Diagram that is currently in use on large-scale charts. Source Diagrams, and now the improved ZOCs, assist seafarers in assessing hydrographic survey data and the associated levels of risk of navigating in a particular area. According to the new edition of the International Hydrographic Organization (IHO) specifications, S-4 navigational charts will provide more information on ZOCs. The current paper discusses these new regulations.
  • Weintrit, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Navigational charts are essential tools for marine navigation. But how accurate are the navigational charts that we use when going sailing? Do we really know how much faith can be placed in them? All charts, whether paper or electronic, contain data, which varies in quality due to the age and accuracy of individual surveys. In general, remote areas away from shipping routes tend to be less well surveyed, and less frequently, while areas of high commercial traffic are re-surveyed frequently to very high levels of accuracy, particularly where under-keel clearances are small. It is quite accurate to consider a chart as a jigsaw of individual surveys pieced together to form a single image. Having the necessary skills to determine how much confidence should be placed in the surveys, which combine to form a chart, should be a requirement for any sailor venturing into unfamiliar waters. When the International Hydrographic Organization (IHO) developed the S-57 standard for Electronic Navigational Charts (ENCs), this problem was recognized and it was decided that the quality of survey data used to compile ENCs had to be encoded within a composite data quality indicator ‘Category of Zone of Confidence’ (CATZOC) to assist seafarers in assessing hydrographic survey data and the associated level of risk of navigating in a particular area. According to IHO S-67, the accuracy of Electronic Navigational Charts is not impressive and leaves much to be desired. The author discusses these apparent shortcomings of ENCs and present erroneous approaches to this problem, so common in the seafaring community.
  • Skorek, Grzegorz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The aim of the article is to look at the possibility of accurately determining the energy efficiency of drive systems. The results of experimentally determined efficiencies and the efficiencies determined from simulations of two hydrostatic systems with throttling control and fed by a constant capacity pump were compared. The research apparatus was very precisely designed, made and automated. The measuring instruments that were used are characterized by their high measuring accuracy. The issues related to the determination of the energy losses and the energy efficiency of the hydraulic motor or drive system, which should be determined as dependent on the physical quantities independent of these losses, were also discussed. A Paszota diagram of the power increase in the direction opposite to the direction of the power flow, replacing the Sankey diagram of the power decrease in the direction of the power flow in the hydraulic motor or in the drive system, was analyzed. The results showed that a Paszota diagram opens up a new perspective on research on the power of energy losses and energy efficiency of hydraulic motors and drive systems.

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