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This paper proposes a model of the interactions between surface currents and small, moving objects. These objects are immersed in water so that the part extending above the water is no larger than a human head. These interactions are defined as the weighted-directed graph. The basis for determining the edge weights are the directions of the surface currents. The speeds of these currents are used to calculate the time of moving objects. According to the modelling method of the surface-current influence on small objects, presented in this paper, it is possible to implement an application supporting search-and-rescue-operation planning. This method can be used to locate small objects, such as survivors, when planning search-and-rescue operations. Thus, the routes of these objects moving together with surface-water masses can be predicted using this method. [ABSTRACT FROM AUTHOR]

Liquefied natural gas (LNG), as one of the main sources of clean energy, has witnessed great growth in marine transportation in recent years. Due to the potential catastrophic consequences in case of a vessel traffic accident, the guidelines of the design of an LNG Port and the regulation of traffic management require that a mobile safety zone be set up for the transit of an LNG carrier, that is, a moving safety area around the carrier that excludes other ship traffic. To study the impact of a safety zone on channel capacity, this paper has presented a mathematical model to calculate the impact ratio of a large LNG ship on channel capacity considering different speeds and sailing modes. As a case study, an approach channel to a new LNG port that was developed in Yueqing bay, Zhejiang province, East China, has been analyzed during the concept design of the port with the aim of receiving ships with a capacity of 145,000 m3. Based on the model, the impact ratio on the whole channel and the segmented channel when a carrier arrives at and leaves the berth has been calculated. The methodology can support the job of port design and vessel traffic management to improve the capacity, efficiency and safety of a waterway. [ABSTRACT FROM AUTHOR]

In this paper a simple four-point, in terms of time, but eight-value in total, identification method has been developed for the second-order linear Nomoto steering model. The algorithm intrinsically uses the zigzag test data in that it inherited some principles of the well-known procedure for the first-order model, from which it is essentially derived. The performance evaluation was then conducted with both simulated and real data. However, the results of these early, unprecedented efforts are far from satisfactory. Some potential sources of difficulties have been discussed. This calls for further research and improvement in order to provide a practical application of the method. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Wind has huge influence on take-off, landing and cruising of aircraft. Therefore measuring wind direction and speed as well as evaluating its structure are the most important tasks in meteorological support of flights. Wind shear, which is characterized by rapid changes of speed and/or direction, is one of the most hazardous phenomena for aviation. This phenomenon exists mostly in low tropospheric jet streams, areas of active atmospheric fronts, near convective clouds and strong temperature inversions. The paper proves that wind shear is mainly dependent on non-uniform layout of ascending and descending air currents and shows that this phenomenon can be detected by using ground sensors (ultrasonic anemometers), remote sensing methods (sodars, radars, wind profilers) and data from numerical mesoscale models. [ABSTRACT FROM AUTHOR]

The procedure of Linear Incremental Model (LIM) identification requires input and output signal deviations as opposed to their actual values. When considering a vessel as a plant, the sequence of input signals determines the traceability of the estimated LIM. The manual input signals selection procedure is a demanding and time consuming empirical procedure. In order to increase the speed of object identification and to eliminate input-output signal sequences which give unreliable data, an incremental linear model identification algorithm was developed and is presented. Moreover, the method of parameter selection for input signal pseudo-random sequences is described in this paper. Emphasis is placed on the practical aspect of astatic objects - ship's LIM creation and input-output signal deviations selection method. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 tofind 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. [ABSTRACT FROM AUTHOR]

During winter in arctic seas, navigation of ships near ports occurs within ice channels created and maintained by icebreakers. Small ice floes fill the relatively narrow navigable channel, and ships are forced to produce the overtaking or opposing separation over short distances and under the action of ice floes. This paper presents an analytical model of the interaction of ships under the conditions just described as well as the results of a simulation. The simulation showed side force and yawing moments were dependent on ice conditions and the ship's dimensions and motion characteristics. [ABSTRACT FROM AUTHOR]

This paper presents the results of analytical studies on determination of vibration characteristics of cylinder liners of diesel engines based on the development and application of mathematical models. Mathematical relationships for cyclic deformations in a longitudinal cylinder sleeve for circumferential and radial directions have been developed. Sufficient convergence of the model with the results of practical measurements given in the literature has been shown. [ABSTRACT FROM AUTHOR]

To forecast the optimum route passage of a vessel in the real weather conditions using the so-called velocity characteristics of the ship. These are developed in the way, as to have a very simple form, which can not guarantee high precision in calculating the speed of the vessel. The paper presents a mathematical model of the external forces operating in the vessel and the algorithm to solve this model for calculating the instantaneous speed of the vessel in the selected weather conditions. Made of a computer program, after appropriate research and testing, can be used to optimize the transport route of the ship. [ABSTRACT FROM AUTHOR]

To forecast the optimum route passage of a vessel in the real weather conditions using the so-called velocity characteristics of the ship. These are developed in the way, as to have a very simple form, which can not guarantee high precision in calculating the speed of the vessel. The paper presents a mathematical model of the external forces operating in the vessel and the algorithm to solve this model for calculating the instantaneous speed of the vessel in the selected weather conditions. Made of a computer program, after appropriate research and testing, can be used to optimize the transport route of the ship. [ABSTRACT FROM AUTHOR]

The contemporary shipping technics wide applies the systems electromagnetic with the shaft -generator. The simulating investigations of transitory processes electromagnetic in such system need the complex model mathematical study, describing the dynamics of objects in him contained. The following article is the first part of the final description of the mathematical model of the shipping system electromagnetics with the shaft-generator. The paper describes external conditions, which can influencing on the course of electromagnetic processes in the systems and there is giving the proposed mathematical model of the Shipping Main Engine as the drive of the Shaft-Generator. [ABSTRACT FROM AUTHOR]

This paper presents reconstruction of the oil spill that occurred as result of an m/t "Baltic Carrier" accident. This reconstruction was carried out with use PISCES II simulator. The result of several simulations could be the step to usability and validation of PISCESS II simulator and as a guideline for setting up this kind of simulations. [ABSTRACT FROM AUTHOR]

This paper presents the results of studies on the influence of unbalance of the rotor unit of a turbocharger on its operational parameters. Identification of the study object, a turbocharger of the NAPIER C-045 type, has been performed. The experiment was carried out at a test stand identifying turbocharger operational parameters belonging to the rotor unit unbalance group. Basing on the measured values and using a mathematical model, hypothetical values of operational parameters for different loads of Diesel engines were calculated. The obtained experimental results were compared to the calculated ones. On this basis, the studied turbochargers were classified into one out of three categories describing operational utility class of a given turbocharger. The order of sensitivity of turbocharger operational parameters to the unbalance of the rotor unit was established. [ABSTRACT FROM AUTHOR]

PISCES II is a simulator designed to conduct research and training related to the rescue operation in the event of an oil spill on any of the world region. The program includes a built-in mathematical model, enables the oil spill of crude oil to observe the interaction in user-specified external conditions. This paper presents the results of the analysis of mathematical model simulation Pisces II, the behavior of the oil slick in selected hydrometeorological conditions. [ABSTRACT FROM AUTHOR]