English Polski
Akademia Morska w Szczecinie

DSpace Home

DSpace/Manakin Repository

45 Scientific Journals of the Maritime University of Szczecin, no. 45 / 2016



 

Recent Submissions

  • Chybowski, Leszek (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Dear Readers, It is with great pleasure that I announce the latest, 45th issue of the quarterly Scientific Journals of the Maritime University of Szczecin. The Journal has been published in the new format for over a year now. During this time, we have developed new publishing procedures, suitable for a modern journal, and directed towards providing open access to faciliate the sharing of peer-reviewed scientific results. We have also succeeded in improving the Journal's score in the official ranking published by the Ministry of Science and Higer Education of Poland, and our score in the Index Copernicus list. Further, the Journal has been indexed in InfoBase and the prestigious Directory of Open Access Journals (DOAJ). All these activites have brought about an increasing interest in the Journal which is attributed to the joint effort of several individuals, including the staff of the Publishing House at the Maritime University of Szczecin, members of the Journal's Scientific Board, reviews, and consultants. As Editor-in-Chief, I would like to express my sincerest apprecation and thanks to all for their invaluable contribution.
  • Kobyliński, Lech (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Currently, ship operators (ship masters and pilots) are trained on ship simulators, either Full Mission Bridge (FMB) simulators, or Manned Model (MM) simulators. Both types of simulator increase an operator’s skill in manoeuvring a ship, and both incorporate the impact of hydrodynamic forces on the handling characteristics of a simulated ship. However, all forces affecting manoeuvring are the result of flow patterns that build up around the hull. These flow patterns may have extremely complex effects on many practical manoeuvres. Recent advances in hydrodynamic theory allow the impact of hydrodynamic forces on manoeuvrability to be simulated quite accurately so long as the simulated ship is moving straight ahead or performing standard manoeuvres. These advances also allow the simulation of such external influences as bank effects, shallow water effects, and canal effects, as well as the effect of the passage of other ships in the immediate vicinity. With a measure of simplification, these effects can be incorporated in FMB simulators. They can also be simulated by MM simulators provided both the models and training areas are properly prepared. As they are now, training simulators do not contribute to a trainee’s understanding of the way in which flow patterns develop or of the forces they create. This article discusses this deficiency and proposes a solution for it. Several examples of specific manoeuvring scenarios are used to illustrate the solution.
  • Kozak, Maciej; Gordon, Radosław; Bejger, Artur (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The paper covers the theoretical background and tests of two asynchronous squirrel cage generators connected to voltage source inverters working in parallel. Inverters were connected in parallel by their intermediate direct current circuits by means of auctioneering diodes, and then to a DC power network. The real-time control algorithm of digital signal processor DSP and field-programmable gate array FPGA was used to achieve proper excitation of two different power machines, and to maintain high enough levels of direct current link voltage. Windings of both generators are fed by use of so-called machine side inverters. The asynchronous generator is a voltage source inverter controlled by a field-oriented control algorithm based on the current machine model. To prove robustness of the chosen algorithm, different types of load were applied while generators and inverters worked in parallel.
  • Praczyk, Tomasz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Autonomous underwater vehicles are vehicles that are entirely or partly independent of human decisions. In order to obtain operational independence, the vehicles have to be equipped with specialized software. The task of the software is to move the vehicle along a trajectory while avoiding collisions. In its role of avoiding obstacles, the vehicle may sometimes encounter situations in which it is very difficult to determine what the next movement should be from an ad hoc perspective. When such a situation occurs, a planning component of the vehicle software should be run with the task of charting a safe trajectory between nearby obstacles. This paper presents a new path planning algorithm for a Biomimetic Autonomous Underwater Vehicle. The main distinguishing feature of the algorithm is its high speed compared with such classic planning algorithms as A*. In addition to presenting the algorithm, this paper also summarizes preliminary experiments intended to assess the effectiveness of the proposed algorithm.
  • Zalas, Ewa; Sanecki, Józef; Klewski, Andrzej; Stępień, Grzegorz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents a method of determining the spatial orientation of measuring sensors. This method is based on isometric space transformation of a rigid body registered in an oblique coordinate system and is adopted for photogrammetric purposes. The approach is based on incomplete coordinate systems used for determination of transformation parameters. In this publication an incomplete coordinate system is one without one of the axes and in which the matching points connected to primary and secondary coordinate systems are on the two other axes. On the basis of angular momentum, translocation of the beginning of coordinate system is determined first. The next step is to calculate the Euler angles – exterior orientation of sensor. In this method the beginning (the center) of the coordinate system is associated with the sensor itself. This approach, in comparison with the methods known from photogrammetry and remote sensing, allows one to reduce the points needed for transformation. In case of determining the Euler angles two points are indispensable and, in case of moving the beginning of coordinate system, three points are essential. At the end of this paper the analysis of transformation, based on independent control points (ICP), was completed.
  • Czaplewski, Krzysztof; Świerczyński, Sławomir; Zwolan, Piotr (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents the authors’ reflections on using integral calculus when preparing the process of locating single ground-based chains of positioning systems in marine navigation. These reflections are purely theoretical and presented research results apply to a hypothetical navigation system that operates based on the ratio of distances, which is regarded as a navigation parameter.
  • Engler, E.; Hoppe, M.; Ritterbusch, J.; Ehlers, T.; Becker, C.; Ehrke, K.-C.; Callsen-Bracker, H. (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Reliable knowledge of a ship’s position and movement in relation to other traffic participants and obstacles is a fundamental requirement for navigation and avoiding collisions and groundings. Consequently, the onboard provision of resilient position, navigation and time data (PNT) is emphasized by the International Maritime Organization’s (IMO) e-navigation strategy, solution S3 “Improved reliability, resilience and integrity of bridge equipment and navigation information” and by the assigned risk control option RCO5 “Improved reliability and resilience of onboard PNT systems”. An initial step towards resilient PNT has been realized by the maritime community with the development of the performance standards for shipborne multi-system radionavigation receiver equipment (MRR). This MRR performance standard (PS) supports the full use of data coming from current and future radionavigation systems and services. Consequently, the combined use of several global navigation satellite systems (GNSS) and the additional use of space based augmentation systems (SBAS) as well as optional terrestrial radionavigation systems (e.g. eLoran or R-Mode) will be supported to increase the performance of positioning and timing. As a second step, the development of guidelines for an onboard PNT (data processing) unit has been identified as supplementary and necessary. The starting point is the onboard use of a combination of GNSS receivers and autarkic systems (e.g. radar, gyro, echosounders with bathymetric data) for a comprehensive provision of required PNT data. Redundancy in the available data enables the application of integrity monitoring functions to evaluate the current usability of safety-critical data and components. The aim of the guidelines is the specification of data processing rules towards the resilient provision of standardized PNT data and integrity information. For this purpose, a modular architecture for an onboard PNT system is introduced and scaled to the need for data input as well as the performance of data output.
  • Galas, Roman; Čokrlić, Marija (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    A state-of-the-art monitoring global navigation satellite system (GNSS) system has been originally designed and developed for various positioning and atmosphere-sensing purposes by the authors and updated to fulfil the challenging requirements for monitoring of ionospheric perturbations. The paper discusses various scientific and technically challenging issues, such as the requirement for an autonomous operating ground GNSS station and how this can be fulfilled. Basic algorithms for monitoring of local ionospheric perturbations with GNSS receivers are described. The algorithms require that inter-frequency hardware biases be known. Although the satellite transmitter biases can be obtain from the IGS services, the user takes responsibility for the estimation of frequency dependent receiver hardware biases and for the control of their variations. The instrumental signal delays are important for timing applications and GNSS monitoring of the ionosphere and are also required for recovering of the integer carrier-phase ambiguities. The paper presents an algorithm for calibration of inter-frequency biases of global positioning system (GPS) receivers and validates the first set of results.
  • Gralak, Rafał; Muczyński, Bartosz; Terczyński, Robert (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents the assumptions for the concept of a full mission ship’s bridge simulator prototype using innovative augmented virtuality technology. A description of a possible development process is provided as well as two potential applications in the field of marine simulation: operator motion tracking techniques, MoCap, which entails interacting with the environment and generating of synthetic images via HUD; and implementation of the latest technology, data gathering and analysis methods, which would replace current visualization methods and equipment used in maritime simulators.
  • Gucma, Lucjan; Bąk, Andrzej; Sokołowska, Sylwia; Hajduk, Jerzy (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents the stages in stochastic ship traffic stream model creation, applied to determine the influence of liquefied petroleum gas (LPG) tanker introduction to Police Port on the Świnoujście–Szczecin waterway. The model is based on the Monte Carlo methodology, and is microscopic (which means that each ship’s model is treated as a separate object possessing given attributes). The model is applied here in order to find the influence of ships with dangerous cargo (LPG tankers in the case study) on regular ship traffic, and hence to establish whether special traffic solutions are necessary.
  • Gucma, Lucjan; Przywarty, Marcin; Budzan, Tomasz; Karwowski, Lech; Vidmar, Peter; Hribar, Uros (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The paper presents the stages of creation of an autonomous historical navigational system simulator working both in real and accelerated time. The simulator allows performance of navigation tasks from the time of the ancient Vikings, as well as to fix a position by using the Decca system on a real Mk21 receiver recreated to cooperate with the artificial Decca system model. The Viking solar compass discovered on Wolin Island in 2013 was the trigger for creating such a simulator as part of a broader exhibition of navigational systems and tools. The main intention of the exhibition is to demonstrate the hyperbolic navigation application that links both systems.
  • Gucma, Stanisław; Ślączka, Wojciech (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents a simulation method for identifying optimal parameters for turning basins on waterways. This method has been used for the detailed design of the Przesmyk Orli Turning Basin in the Port of Szczecin. Methods of this type allow the parameters of a turning basin to be optimized so long as the facility is fixed in one location.
  • Guze, Sambor; Smolarek, Leszek; Weintrit, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In this paper, two indexes for own ship risk collision assessment in the restricted water are proposed. The first one concerns the collision threats for ships. The second one describes threats that are generated by human error. It is carried out dynamically with accordance to changes in time. To realize the main aim of the paper, the definition of the extended domain of the ship is introduced. Furthermore, the rules to determine the indexes and range of their values are developed. Finally, a comprehensive model and its potential application are presented. There are some important things to take into account during the model development: the interface, the levels and type of the output information, the type and accuracy of the information about the position and movement dynamics of the particular ships. It gives the opportunity to consider the different operation levels. In addition, it also allows us to take into account the different levels of measurement and the collision risk warnings. This approach can be helpful for both the VTS operator and OOW, the ship’s navigator, as the tool to support the safe navigation in restricted water.
  • Kasyk, Lech; Pleskacz, Krzysztof; Bugajski, Grzegorz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Search patterns and procedures contained in the International Aeronautical and Maritime Search and Rescue Manual for Mobile Facilities meet the requirements of theoretical assumptions about search and rescue operations. But the individual manoeuvrability characteristics of a search vessel cause real search and rescue operations to differ from theoretical patterns. This article analyses the difference between theoretical and actual search regions in a Diagram of an Expanding Square Search. Different variants of parameters of ship manoeuvrability have been considered. Some solutions modifying the Diagram of Expanding Square Search are proposed by the authors.
  • Anczykowska, Anna; Ślączka, Wojciech (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents a comparison between the use of analytical methods and simulations for dimensioning the approach to the liquefied natural gas (LNG) terminal in Świnoujście. Parameters of rectilinear sections of the fairway were obtained by analytical methods, widely used in traffic engineering. These methods are: the method of the Three Components, the Panama Canal method, the Canadian method, the method of the INM and the PIANC method. Dimensioning the approaching fairway to the LNG terminal in Świnoujście was conducted for two types of LNG tankers: Q-flex and Q-max. Results for simulation methods were obtained using a navigational bridge simulator. Results obtained using analytical and simulation methods allowed the comparison of parameters of the approach to the LND terminal in Świnoujście, and an indication of the optimal dimensioning methods of a fairway’s straight sections.
  • Juszkiewicz, Wiesław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Closest point of approach (CPA) is a basic factor taken into consideration for risk assessment during the meeting of two ships at sea. Navigators should use radars with automatic target tracking for collision avoidance and should know the accuracy to which radar data are calculated. Basic information about these requirements can be found in IMO resolutions. The currently binding document for devices manufactured after 2008 is IMO Resolution MSC.192(79). But there are two independent requirements for relative motion. One of these refers to relative motion parameters (relative course and speed) and the other one to the value that is the result of this motion (CPA). The other important document is Standard 62388. This specifies the minimum operational and performance requirements, methods of testing and the required test results published by IEC and also refers to radar equipment. However, this standard is not so popular in different publications focusing on radar equipment, so these requirements were not analyzed in the article. The main problem described in this paper refers to the mutual consistency of IMO Resolution requirements. The results of simulations and their analysis are presented.
  • Kołowrocki, Krzysztof; Soszyńska-Budny, Joanna (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Basic concepts of the safety analysis of ageing multistate systems are introduced. The system components and the system multistate safety functions are defined. The mean values and variances of the multistate systems’ lifespans in the safety state subsets and the mean values of their lifespans in the particular safety states are defined. The multistate system risk function and the moment of exceeding the critical safety state are introduced. A series safety structure and a parallel-series safety structure of the multistate systems with ageing components are defined and their safety functions are determined. The multistate system safety models are applied to the prediction of safety characteristics of a maritime ferry.
  • Kowalski, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The aim of the following article is to analyse the lying of a vessel at anchor in extreme hydrometeorological conditions. As an example it describes the situation of the Panamax type bulk carrier anchoring in Prince Rupert harbour restricted area. The investigation takes into consideration the impact of strong wind on the safety of anchoring in sheltered waters. The presented calculations concern problems of slewing which result in changes of heading. The analysis also includes a description of the wind and current forces. The final part focuses on conclusions whose aim is to improve anchoring safety standards in areas managed by harbour authorities.
  • Królikowski, Andrzej; Wawruch, Ryszard (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The European Commission, European Maritime Safety Agency (EMSA) and Member States of the European Union have expanded the scope of operation of the Vessel Traffic Monitoring and Information System (VTMIS). This project was established in accordance with the requirements of the Directive 2002/59/EC of 27 June 2002. Part of these measures are currently implemented in Poland and are co-financed by the European Union (EU) project entitled “National Maritime Safety System – KSBM”. It is implemented with a time delay in two stages: KSBM-I and KSBM-II. KSBM-I was located on the main list of individual projects of the Operational Programme “Infrastructure and Environment” for 2007–2013. The project is realised with the support of EU funds financed in the Priority VII “Environmentally-friendly Transport” under Measure 7.2 “Development of Maritime Transport”. The works were and are based on contracts signed 28.02.2011 (Stage I – KSBN-I) and 20.12.2012 (Stage II – KSBN-II). The first stage involved the purchase and installation of radar, computer and radio equipment and construction of radio communication network. The second was related mainly to the wire communication network. The system covers Polish coastal waters and seaports from Szczecin and Świnoujście to the border with the Kaliningrad Region. This paper presents concept of the system and the state of its implementation.
  • Perkovic, Marko (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The high volume transported by ro-ro vessels has not come without a price. Accidents and incidents related to design – lack of bulkheads, instability, problems with cargo access doors, stowage, securing cargo and lifesaving appliances – are growing along with the size of the vessels themselves. One particular and recurrent problem is the degree of these giant box-like high riding vessels exposed to wind. Recently the effect of a tramontana – a fierce, sudden and short term regional wind – in the Port of Koper was to detach a moored ship, causing an accident. This paper will present a study of that accident, and through simulations and modelling determine an improvement that will allow berthing perpendicular to the stern ramp to function more securely.
  • Pietrzykowski, Zbigniew; Magaj, Janusz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Ship movement processes in selected Traffic Separations Schemes (TSS) of Southern Baltic Sea were analyzed. Ship domains in the analyzed water areas were calculated from Automatic Identification System (AIS) registered data. The purpose of investigation was identification of ship domain parameters taking into account different domain determination criteria. The results were compared and discussed. The conclusions were drawn.
  • Zalewski, Paweł (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    We propose a Marine Vessel Protection Area (MVPA) model as the means of satellite-based augmentation system (SBAS) integrity data presentation in an electronic chart system (ECS) display. The model takes into account several factors that influence the shape and dimensions of the MVPA. These factors include GNSS signal aspects, where measurement errors depend on the geometry of visible satellites and the signal propagation, the ship’s size, the ship’s heading and its estimated accuracy, position of the GNSS/SBAS antenna relative to the ship’s hull, and SBAS integrity data. The resultant safety contour or domain can be displayed within the ECS or ECDIS as a graphical representation of the marine ship position and the protection level of the electronic position/course fixing equipment, equivalent to the horizontal protection level (HPL) used in aviation.
  • Filipowicz, Włodzimierz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In most problems encountered in navigation, imprecision and uncertainty dominate. Methods of their processing rely on rather obsolete formalisms based on probability and statistics. Available solutions exploit a limited amount of available data, and knowledge is necessary to interpret the achieved results. Profound a posteriori analysis is rather limited; thus, the informative context of solutions is rather poor. Including knowledge in a nautical data processing scheme is impossible. Remaining stuck with the traditional formal apparatus, based on probability theory, one cannot improve the informative context of obtained results. Traditional approaches toward solving problems require assumptions imposed by the probabilistic model that exclude possibility of modelling uncertainty. It should be noticed that the flexibility of exploited formalism decide the quality of upgrading models and, subsequently, on the universality of the final results. Therefore, extension of the available formalisms is a challenge to be met. Many publications devoted to the mathematical theory of evidence (MTE) and its adaptation for nautical science in order to support decision making in navigational processes have enabled one to submit and defend the following proposition. Many practical problems related to navigational ship conducting and to feature uncertainty can be solved with MTE; the informative context of the obtained results is richer when compared to those acquired by traditional methods. Additionally, a posteriori analysis is an inherent feature of the new foundations. The brief characteristics of a series of publications devoted to the new methodology are the main topics of this paper.
  • Kotkowska, Diana; Gucma, Lucjan; Marcjan, Krzysztof (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The vessel traffic system (VTS) operator is an important role in the monitoring and supervision of maritime traffic. The main objectives of the VTS is to improve security in the coastal areas. VTS efficiency depends on the quality of the operators. Certain conditions of work should be provided if the system service is to be reliable as this facilitates proper and effective task performance. This article analyzes the factors affecting the performance quality of VTS operator’s. The aim of this study is to examine the methods that indicate negative factors affecting the efficiency of the VTS operator. The result of the study is primarily a reliability analysis of VTS, which underlines the importance of a thorough understanding of the factors associated with human reliability. These methods are crucial to determining VTS operator errors, and gaining an understanding of the consciousness of the operator’s actions in the workplace. Future negative factors can potentially be eliminated by answering questions about the guiding forces, actions and reactions of the operator to external stimuli in a specified scenario.
  • 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.
  • Lushnikov, Evgeniy; Pleskacz, Krzysztof (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article looks into the role of the magnetic compass in providing navigational safety of a ship. Existing requirements for the magnetic compass at the presence of satellite navigation are not economically justified. Therefore, a new rational requirement is proposed for the accuracy and frequency of deviation compensation work. This proposal assures the safety of navigation and its cost-effectiveness. A lab experiment has verified the proposed method.

    There are no files associated with this item.

  • Makar, Artur (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    In this paper, a method of mathematical description of a surface, which can be used for modeling the sea bottom and detecting underwater objects using sonar (a side scan sonar or a front one) or a multibeam echosounder, is presented. The method is based on Coons plates and is described in four steps, which can be used for determination of the sea bottom for spatial presentation and volume calculation. A new sounding vessel and its equipment were used for the collection of geospatial data, and the results of a geospatial model of the sea bottom on the basis of the collected data are shown. The sea bottom is presented using Coons surfaces and a triangulated irregular network.
  • Małyszko, Marzena; Wielgosz, Mirosław (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This article presents the concept of a decision support system for maritime search, rescue and salvage operations. It describes the main ideas for systems in three areas of maritime rescue – search and rescue (saving lives), salvage (saving property at sea), and environment protection operations. It contains an analysis of the factors influencing the decisions of both marine navigators and shore-based centres. The general ideas of the systems are presented in the form of flow charts. An analysis was made of input data, working procedures, and the decisions based on these data and procedures. The simplified algorithm of the system is described. The principles of system utilisation are explained, developmental trends are described, and conclusions are drawn.
  • Przywarty, Marcin (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    This paper presents the process of quantitative assessment of selected factors influencing the probability of grounding. All grounding accidents that occurred during one year (2013) in the Baltic Sea area were analysed. The research area was chosen because of very high traffic intensity and a large number of narrow passages that make it difficult for navigation. The research period was limited by the latest data reported by HELCOM up to the year 2013. The Method of Grounding Probability Coefficient (GPC) calculation is proposed to reach the assumed goal. Either internal factors such as the ships size and ship type or external factors such as time of day, wind force and season were taken into account. As a result the values of coefficients describing the impact of various factors on the probability are evaluated. This coefficients, taking into consideration coupling effect, can be used in future in the navigational safety simulation models based on the assumed value of accident probability.
  • Smolarek, Leszek; Kaizer, Adam (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    Since there is a tendency that new build vessels are increasing in size, dredging has become an important part of the development and maintenance strategy for ports serving the largest ships. The increase in the technical depth of vessels drives additional development of the entire port. However, the effectiveness of this type of project depends heavily on unrestricted traffic and uninterrupted operation of the terminal. This paper presents a modelling of various type of dredging activities in ports based on an existing work schedule. A tool used to queue work activities with a vacation was used in this effort. The methodology of creating a dredging time schedule in the port area depended mainly on disentangling interference caused by the ship traffic and dredgers trying to work at the same time.
  • Walus, Artur; Gucma, Lucjan; Putynkowski, Grzegorz (Scientific Journals Maritime University of Szczecin, Zeszyty Naukowe Akademia Morska w Szczecinie, )
    The paper presents a turning method saving time and energy while conducting seismic surveys and an example of its application. The introduced turning method is based on use of the ocean currents / tidal streams as a supporting factor. The turning technique is applicable for vessels towing streamers and conducting line-change or other maneuvers similar to 180° turn. Chosen forces affecting seismic in-water equipment as well as behavior of the spread are briefly shown and explained. Some advantages over traditional turning techniques are here described. The method was applied onboard the seismic vessel Geo Pacific reducing significantly time required for line-change.

Search repository

Advanced Search

Browse

My Account

RSS Feeds