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.
In this paper an example of speed down curve construction for one ship type is pre-sented. The relationship between ship’s speed changes and environmental factors is defined on the basis of observational data. The artificial neural network was used for a regression analysis. Taking into account the fact that input data imprecision can hardly be avoided, which consequently makes the predicted ship speed approximate, the proposed notation of ship speed in given conditions has the form of fuzzy number.
The changes in political situation that have taken place over the last several years and an advancing globalization have put the problems of international shipping safety among the most important problems of the world today. New threats such as maritime terrorism, piracy and armed attacks have become a new challenge to marine transport. The article characterises certain operations below the war level, i.e. shipping control and protection. The authors define and specify the operations associated with the protec-tion and control of the shipping.
Correct preparation of the crew for work can be obtained via long-lasting appren-ticeship at sea, or training at simulators. The simulator of the moving ship in the marine environment is presented. It has an ability to realize different training scenarios and the follow-up action of training in real-time. The simulator makes it possible to test the ship steering systems, to verify the collision avoiding systems, the testing of the autopilot etc.
Passing a restricted area the ship’s master has to select one of the alternative routes or decide on a delayed passage. Among important imprecise and subjective val-ues are congestions encountered within the regions including route crossings or junc-tions. To foresee traffic within a confined area the decision maker has to cope with im-precision and to use fuzzy numbers. Fuzziness is expressed by intervals. Interval arith-metic embraces typical operations such as addition or multiplication, but also enables the selection of possibility level as well as the comparison of such values. Consequently, extended popular hierarchy builders can be used for the selection of the best option.
This article presents selected probabilistic models used for the description of ship’s position in restricted areas. Two models based on a joint of normal and uniform distri-butions have been discussed in detail. These models can be applied for the estimation of accident probability and manoeuvring risk taken by ships sailing in restricted areas.
This article presents a method of pilot navigation systems research and the parame-ters of a PNS prototype developed after the second stage of optimization.
The vessel traffic in the Western Baltic Sea area is characterized by high concen-tration. This area is difficult for navigation. By a decision of the International Maritime Organization (IMO) new traffic separation schemes will be mandatory for ships from 01.07.2006. The question is if this new solution will be satisfactory for maritime admin-istration and navigators and if all problems willbe solved.
The main goal of tracking systems is providing the observer with a proper safety assessment, including a possibility of proper and effective trial manoeuvre planning. For the trial manoeuvre accuracy examination, some typical scenarios were simulated in a radar simulator. The research results of trial function accuracy are presented in the article.
The paper presents guidelines for the determination of ship aerodynamic forces with the application of computational fluid dynamics methods. Numerical calculations were verified against the results from the wind tunnel. The techniques of grid making and furhter grid adoption for local flow characteristics were discussed. Special attention was paid to the problems of time limitations during grid generation and automation of thge computation process.
New Load Lines regulations came into force on 01.01.2005. This is the result of the long time preparations within IMO SLF Sub-Committee. The work was aimed at the review of the provisions of the LL Convention and, in particular, revision of freeboard tables based on deck wetness concept. This aim was only partially achieved. The first part of the LL Convention including conditions of assignment was totally re-drafted, but freeboard tables were not changed. The subject of revising freeboard tables was eventu-ally deleted from the work programme of IMO.
This paper attempts at bringing the methods of maritime safety assessment closer to the seafarers and the entire maritime industry. The Formal Safety Assesment (FSA) methodology is discussed briefly, then focus is made on safety assessment methods applied for setting up the different elements of the navigational infrastructure.
Marine accidents are rather frequent as the elimination of all hazards to human health and life is still impossible. In every case the evacuation from the ship must be taken into consideration. The layout and marking methods should be continually im-proved to increase the safety level of voyages. The paper describes evacuation routes designing and marking. This knowledge can be utilized by interior designers in choosing safety euipment and by researchers who analyse the evacuation of personnel and pas-sengers in emergency situations.
The article deals with problems of ship’s navigational safety, difficulties existing in attempts to formalize the automation of navigation. Criteria of ship's navigational safety existing today are considered, as well as errors related with these issues. The author also takes into consideration the problems to be solved, and expresses a need for the perfection of such important documents as COLREG-72, Accuracy Standard for naviga-tion and others.
This article is a continuation of considerations on the measures determining fair-way traffic capacity. It refers to rational choice of traffic capacity for acceptable opera-tional conditions. The theoretical foundation has been supported with examples of real values of quantities identifying the process of vessel traffic. It has been shown that the method is useful in determining measures of choice capacity characteristics of a marine traffic engineering system. Important practical conclusions have been drawn.
The Operational Safety of Man – Composed Transportation Systems.
In the article the problem of artefacts in the block compression of sea-floor surface data is presented. The cause of such artefacts as well as an appropiate solution are included. In the end the complete compression algorithm dealing with the boundary effect is proposed.
The most beneficial ship’s route calculations on the ocean are presented, taking in-to consideration tropical cyclone avoidance. Tests were made for the m/v “Daszynski” voyage using real weather data during 26.IX.04 - 06.X.04, when the North Atlantic was haunted by the tropical cyclons “Jeanne” and “Lisa”. A computational program based on evolutional algorithms was used.
Ship’s parameters are an essential factor taken into consideration when ship’s safe-ty is assessed in a navigational situation in a restricted area. The ship’s fuzzy domain is one of the assessment criteria. Its determination is based on the representation of previously acquired navigators’ knowledge combined with methods and tools of arti-ficial intelligence. This article presents research results and a preliminary analysis of how a ship’s size affects the shape and size of its fuzzy domain.
The paper describes a few aspects of the vessels' safety in a sea port, taking into consideration the effect of location of cargo-handling and berthing quays for vessels with dangerous cargo. The concept of "danger zone" in the port has been defined, based on the possibility of either force-majored or intentional threats of collisions with other vessels, and threats created by neighbouring cargo-handling stations. Protective measures have been suggested in compliance with the ISPS convention and EU require-ments.
In the paper some problems of quantitive description of traffic safety in various branches of transport are presented. Basic definitions and a concept of traffic safety in transport is given. Some methods of dimensioning traffic safety are proposed, especially geometrical methods that are useful in short-term traffic control.
In many cases the system structure of drifting rescue units (DRU) is not so im-portant as its operational functioning. The DRU failure is caused not only by DRU sys-tem changes, but is adversely affected by environmental factors (action of wind, cur-rents, and waves).
A method of constructing a Numerical Terrain Relief Model dedicated to fairways is presented. The method is based on approximated cross-sections using RBF networks with an incremental selection of radial neurons number. Adaptive cross-sections adjust to the model surface and to an error assumed by the user, which reduces the amount of data and makes it possible to visualize the surface in real time. The research made use of test surfaces as well as real measurement points located in the Szczecin – Świnoujście fairway.
The article deals with a problem of multisensor navigational data fusion. The mul-tisensor Kalman filter’s configuration is given. The filter has been developed to deter-mine an object vector based on uniform data obtained by a set of satellite receivers.
The paper presents the results of empirical study on the precision of public transport vehicles' localization in areas with different degrees of urbanization. The pa-per also discusses the premises for the creation of fleet management system for public transport and typical configurations of such systems. Particular attention is devoted to the localization of public transport vehicles in the street network. Finally, the paper presents the approach to city bus localization adopted in a project of the system for public transport management in Warsaw.
One of shipowner’s requirements that the shipyard has to satisfy is the designed ship speed. In real weather conditions a ship is affected by forces from wind and waves resulting in additional changeable resistance and ship’s speed loss. The article presents a method for calculation of the mean statistical ship speed for a given ship over a long time period during an operation on a selected ocean route.
The paper presents results of calculations based on a method discussed in the paper . The results are given as bar charts with performance of ships (mean statistical speed) dependent on an ocean route and the size of a ship. Statistical weather data on a particular ocean route are taken into account.
The article presents a method of stochastic modeling of a GNSS position error. Pre-liminary results of DGPS error simulation are presented, a simulation algorithm is de-scribed as well as its application in sea traffic engineering research.
Solving problems of vessel traffic organisation in narrow fairways can be treated as an optimisation problem with the criterion of time function optimisation. The article presents a mathematical model of vessel traffic that can be used in narrow fairways with low traffic intensity. To solve the problem, an adapted algorithm was applied. The re-sults are illustrated with solutions for chosen data.
Ship’s safety requires continuous identification and assessment of the navigational situation. The assessment of own ship’s safety is often reduced to watching the estab-lished zones around the ship. The safety level is decreased when another object disturbs the established zones, which requires evaluating the risk and making adequate coun-termeasures. The situation when we have to maintain an adequate level of safety leads to another approach, i.e. it requires navigating the ship within an established zone (traffic separation scheme). In the paper different kinds of ship’s zones and their purpose are presented.
On the basis of the navigational technology development the author points out the demand for professional competence increase. He presents contemporary trends in edu-cational changes and suggests teaching methods and forms geared to subject-oriented systems of education. The author emphasizes the role of competence growth as a steady process ensuring usefulness and opportunities of employment.
This article introduces a complex model of technical meansmaintenance process that can be applied for decision making in outcourcing and service contracting prac-tice. The integrated computer tool, using the model was also described.
The analisys of navigational and weather restrictions for vessels navigating to the port of Svea has been made.
The article presents two methods of determining safe waterway parameters in con-fined waters, based on real experiments. The methods have been developed at the Insti-tute of Marine Traffic Engineering.
The paper presents a verification of the optoelectronic experiment based method, by means of another method using RTK GNSS techniques.
The paper refers to the tracking system nonlinear control synthesis via the sliding mode control where it is assumed that there is an unknown nonlinear function in the object model. It has been pointed out that the presented approach may be directly gen-eralized to the much more advanced case, consisting in adaptive approximation of un-known function by means of AI aproximators. The system operation has been illustrated with an example of ship course keeping problem.