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EN
The proper selection of statistical distributions is important for modeling port operations using simulations or queuing theory. The aim of this study was to determine the appropriate statistical distributions for modeling random processes related to ship operations in ports, including ship arrivals, berthing maneuver processes, service processes, and unberthing maneuver processes. A literature review was performed on the statistical distributions used in these random processes. In addition, the port data on ship operations gathered from three different ports in Turkey were examined. Goodness of fit tests were conducted to determine the appropriate distribution for each process.
EN
Fear of the invisible enemy, as is commonly called bacteria and viruses that disturb or take away health, has accompanied mankind for thousands of years. The article presents cases of illness caused by a biological factor among passengers and crew members on ships. The author mentioned incidents that have occurred in the past. Above all, however, the author’s considerations focused on the current situation (Pandemic COVID-19) the threat of biological factor on vessels.
PL
Strach przed niewidzialnym wrogiem, jak zwykło się określać bakterie i wirusy nierzadko zaburzające lub zabierające zdrowie, towarzyszy ludzkości od tysięcy lat. W artykule przedstawiono przypadki zachorowań spowodowanych czynnikiem biologicznym wśród pasażerów i członków załóg na statkach. Wspomniano o incydentach, które miały miejsce w przeszłości. Wiodące rozważania Autora skupiły się na obecnej sytuacji (Pandemia COVID-19) zagrożenia czynnikiem biologicznym na jednostkach pływających.
EN
This article presents an analysis of vertical shear forces and bending moments during nodule loading in the case of a standard bulk carrier around the Clarion–Clipperton Zone. An operational efficiency index was applied to an assessment of internal forces during loading which took into account wave heights and periods around this zone. The aim of this research was to investigate whether waves could have a negative effect on loading efficiency and to estimate the nodule mass that can safely be loaded onto a standard bulk carrier taking these waves into account. Moreover, a calculation was made to discover the acceptable vertical shear force percentage limit, while also taking into account wave activity during loading.
4
EN
A ship built from ferromagnetic steel disturbs the uniformity of the Earth’s magnetic field. Changes of ship’s signature are due to the magneto-mechanical interaction of the hull with the Earth’s magnetic field. The ship’s magnetic field can be detected by a magnetic naval mine. For this reason, the vessel has to be demagnetized. There are several methods of ship’s de-perming. The results of experimental and computer simulations of the ship’s de-perming process using coils lying on the seabed are presented in this paper. The simulation of the de-perming process with a hysteresis model of ship’s steel was carried out in Opera-3d 18R2. The laboratory experiments were carried out using a physical ship’s model, several Helmholtz coils, magneto-resistive sensors, etc. The experiments and computer simulations have shown that ship’s de-perming with coils lying on the seabed is possible. The values of coil currents are over dozen times greater than those used in the standard method.
EN
Hydrostatic parameters of a ship are very important in ship design. The importance of the parameters compared to one another need to be revealed in realm of uncertainty, so as to avoid design error. In view of this, a fuzzy-analytical hierarchical process (Fuzzy-AHP) method is utilized in addressing the subject under investigation. The fuzzy logic is used to address uncertainty in pairwise comparison exercise, so as to facilitate the estimation of order of importance of hydrostatic parameters. In this research, the engineering judgements of three designers in analysis of importance of hydrostatic parameters are aggregated and processed using the Fuzzy-AHP methodology. The result produced in the study showed that hydrostatic parameters are importance in order of moments of inertia of vessels (MIV), mass displacement (MD), tons per centimeter immersion (TPCI), coefficients of form (CF), centers of buoyancy (CB), metacentric heights of vessels (MHV), ship waterplane area (SWA), longitudinal center of floatation (LCF), volume displacement (VD) and wetted surface area (WSA) with weight values of 0.218, 0.095, 0.078, 0.083, 0.074, 0.1, 0.46, 0.108, 0.209 and 0.028 respectively.
6
Content available remote Safety of sea vessels in the aspect of model research
EN
The article presents a modern method of modeling stability and unsinkability of vessels using physical models of warships and merchant ships. Model tests of watercraft are carried out primarily to assess their marine properties in various operational states. The purpose of this research is to create technically useful calculation methods for forecasting the behavior of a vessel at sea in various meteorological conditions. The main role played by model tests and measurements on real objects is the verification of these methods. Both types of experiments are also a source of inspiration for creating new modified mathematical models and accounting methods based on them. These tests can contribute to the improvement of the safety of vessels at sea.
PL
W artykule przedstawiona została nowoczesna metoda badań modelowych stateczności i niezatapialności jednostek pływających z wykorzystaniem modeli fizycznych okrętów wojennych i statków handlowych. Badania modelowe jednostek pływających prowadzone są przede wszystkim do oceny ich właściwości morskich w różnych stanach eksploatacyjnych. Celem tych badań jest tworzenie technicznie użytecznych rachunkowych metod prognozowania zachowania się jednostki pływającej na morzu w różnych warunkach meteorologicznych. Natomiast główną rolę, jaką pełnią badania modelowe oraz pomiary na obiektach rzeczywistych jest weryfikacja tych metod. Oba rodzaje eksperymentów są też źródłem inspiracji do tworzenia nowych zmodyfikowanych modeli matematycznych oraz opartych na nich metod rachunkowych. Badania te mogą przyczynić się do poprawy bezpieczeństwa jednostek pływających na morzu.
EN
The issue taken in the article concerns vessels using gas turbine engines as part of propulsion systems and is an addition to previously conducted research in the field of vessels impact on the environment. The author's purpose was to determine the impact on the natural environment of the frigate's operation, in the aspect of ecological indicators. As part of research, measurements of harmful compounds concentration in the engine exhaust during frigate's cruise with simultaneous registration of engine operation parameters were carried out. The obtained results from the conducted measurements were the subject of a comparative analysis with the engine load values. The comparison of the obtained data made it possible to assign concentration values of particular harmful exhaust compounds to the appropriate engine load conditions during the cruise. On the basis of the analyzes carried out, emission factors for harmful exhaust emissions were determined. These factors allow determining the mass of harmful compounds emitted to the atmosphere from marine gas turbine engines during the operation of the Oliver Hazard Perry frigate.
PL
Zagadnienie podjęte w artykule dotyczy oceny wpływu jednostek pływających wykorzystujących w układach napędowych turbinowe silniki spalinowe na środowisko. Celem jest określenie oddziaływania na środowisko naturalne człowieka eksploatacji okrętu klasy fregata, w aspekcie wskaźników ekologicznych. W ramach badań przeprowadzono pomiary stężenia związków szkodliwych zawartych w spalinach silników podczas rejsu okrętu z jednoczesną rejestracją parametrów pracy silników. Uzyskane wyniki z przeprowadzonych pomiarów poddano analizie porównawczej z wartościami obciążenia silników. Wspólne zestawienie uzyskanych danych umożliwiło przypisanie wartości stężenia poszczególnych związków szkodliwych spalin odpowiednim stanom obciążenia silnika w trakcie rejsu. Na podstawie przeprowadzonych analiz wyznaczono wskaźniki emisji związków szkodliwych spalin. Wskaźniki te umożliwiają wyznaczenie masy emitowanych do atmosfery związków szkodliwych zawartych w spalinach okrętowych silników turbinowych podczas eksploatacji okrętu typu Oliver Hazard Perry.
EN
Pollution emission tests from turbine engines used for the main propulsion of vessels require measurement of the concentration of harmful compounds in the exhaust and assessment of the exhaust gases mass generated by the engine. The concentration of harmful compounds can be determined in a direct way by measuring it in the stream of exhaust gases. However, due to the large output of exhaust gases, the mass of exhaust gases must be determined indirectly. To do this it is necessary to carry out a series of tests and analyzes that will enable parameterization of operating conditions. The obtained parameters and functional relations between them can be used to assess the mass of generated exhaust gases. The article presents analyzes related to the methodology for assessing the mass of exhaust gases generated by the main propulsion turbine engine of the vessel, and the manner of their use in the assessment of emission of harmful exhaust gases.
10
Content available Determinanty zarządzania jednostka pływającą
PL
W artykule omówione zostały czynniki kształtujące sposób zarządzania jednostka pływającą.
EN
Paper discussed The indicated preliminary analyzes show incomplete knowledge about shaping the ship management model. It is difficult to determine the best way to manage a ship. Defining the main threat for this watercraft, ie: collision, grounding, terrorist attack will allow more accurate assessment of determinants that depend on the type of ship.
EN
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.
EN
The paper presents the general principles of requirements engineering with particular attention for the requirements specification presented on the example of an ambitious national program for the fleet expansion of the Polish Navy. The introduction outlines the origins of requirements engineering and its strong relationships with software engineering. It appears that most large IT projects usually struggle to meet the precisely formulated criteria of requirements engineering, which results in the tremendous waste of project resources. Next the concept of requirements and good practices in the preparation of requirements specifications is formulated. Later the example of the 15-year history of the Polish Gawron-class corvette, Project 621, is used to illustrate how systematic violations of the cardinal principles of requirements engineering and disregard for regulations can lead to major losses and consequently to suspending the whole project. An emergency solution was planned to conduct the thorough modification of the project so as to complete this very costly investment (about PLN 1 billion) and construct a much weaker patrol vessel – Ślązak, Project 621/M. The main research thesis can be limited to the statement that amateur and improvised requirements specification in the case of a large shipbuilding project, which was mainly based on socio-political needs, leads directly to the collapse of the project and significant material losses accompanied by the painful embarrassment of state bodies on an international scale.
PL
Transport dużej ilości ładunków, prace wydobywcze, przewóz dużej liczby pasażerów drogą morską jest obarczony znacznym ryzykiem, nawet przy wykorzystaniu najnowszych technologii. W niedalekiej przeszłości tysiące ludzi straciły życie w katastrofach m.in. statków, wież wiertniczych i innych obiektów oceanotechnicznych. Przyczyną ok. 80 % wypadków na morzu jest podejmowanie błędnych decyzji przez osoby pełniące wachty morskie na mostku, zwłaszcza w trudnych warunkach nawigacyjnych lub pogodowych. Wypadki mogą być również skutkiem niewystarczającego wyszkolenia lub niedysponowanie odpowiednim zapleczem materiałowotechnicznym. Dlatego też istotne jest, by marynarze byli szkoleni zgodnie z najwyższymi standardami. W referacie przedstawiono opis stanowiska do badań modelowych stateczności i niezatapialności jednostek pływających. Zakres badań i szkolenia załóg może obejmować zarówno stateczność statyczną, dynamiczną jak i awaryjną. Stanowisko to umożliwia także przeprowadzenie analizy wpływu swobodnej powierzchni cieczy występującej w przedziałach lub zbiornikach po uszkodzeniu kadłuba okrętu oraz analizy wpływu przyjmowania, przesuwania i zdejmowania ciężarów na stateczność początkową okrętu. Doświadczenia zdobyte na stanowisku badawczym prowadzą do bliższego poznania zjawisk występujących w bieżącej eksploatacji okrętu oraz do poprawy bezpieczeństwa pływania. Celem artykułu jest przedstawienie wybranych scenariuszy do badań modelowych jednostek pływających oraz zapoznanie z konstrukcją wybranych typów modeli okrętów i możliwościami stanowisk badawczych stateczności i niezatapialności w aspekcie poprawy bezpieczeństwa wykonywania zadań na morzu.
EN
Transport of large amounts of cargo, mining and exploiting natural mineral resources, carrying large number of passengers by sea are characterized by high risk, even if the latest technologies are employed. It is not a long time ago that thousands of people lost their lives in catastrophes of ships, off-shore oil rigs and other marine objects. It is estimated that around 80% of accidents at sea are caused by making wrong decisions by persons keeping watch on the bridge, especially during difficult navigational and weather conditions. Accidents can also be caused by lack of skills necessary for crews or absence of appropriate tools. Therefore, it is important that seafarers should be trained in accordance with the highest standards. The scope of crew research and training may include both static, dynamic and damage stability. This stand bad also enables the analysis of the influence of the free surface effect of the liquid occurring in the compartments or tanks after damage to the ship's hull and the analysis of the impact of cargo operation on the ship's initial stability. Experiences gained on the research stand lead to a better understanding of the phenomena occurring in the current operation of the ship and to improve the safety of swimming. The aim of this article is presentation selected scenarios for the model tests of vessels and to familiarize with the construction of selected types of ship models and the capabilities of stability test stands in the aspect of improving the safety at sea.
EN
The use of new energy generation technologies such as solar energy and electric propulsion technologies to form integrated power propulsion technology for ships has become one of the most concerned green technologies on ships. Based on the introduction of the principles and usage patterns of solar photovoltaic systems, the application characteristics of solar photovoltaic systems and their components in ships are analyzed. The important characteristics of the marine power grid based on solar photovoltaic systems are explored and summarized, providing a basis for future system design and application. Photovoltaic solar cells are made using semiconductor effects that convert solar radiation directly into electrical energy. Several such battery devices are packaged into photovoltaic solar cell modules, and several components are combined into a certain power photovoltaic array according to actual needs, and are matched with devices such as energy storage, measurement, and control to form a photovoltaic power generation system. This article refers to the basic principle and composition of the land-use solar photovoltaic system, and analyzes the difference between the operational mode and the land use of the large-scale ocean-going ship solar photovoltaic system. Specific analysis of large-scale ocean-going ship solar photovoltaic system complete set of technical route, for the construction of marine solar photovoltaic system to provide design ideas.
15
Content available remote Zastosowanie falowników Danfoss w napędach hybrydowych statków
PL
W artykule przygotowanym przez firmę Schulz Infoprod, która od wielu lat współpracuje z Danfoss jako Autoryzowany Dystrybutor, przedstawiono rozwiązanie przemysłowego napędu hybrydowego spalinowo-elektrycznego z silnikiem elektrycznym zasilanym z akumulatorów z falownikiem DC/AC.
EN
The article presents the methodology of calculation of principal parameters of ship’s hull dimensions, called „significant ships list”, at preliminary stage of design process. Knowledge collected in the database is related to new buildings classified according to type, displacement, or DWT, shipping class, maximum speed etc. Are analysed dimensional constraints due of Froude Number, ships dimensional coefficients block and weigh coefficient, relations of main dimensions such as L/B, B/T, L/H, B/H etc. [7]. Those parameters coming out from ship-owners requirements like type of ship, load capacity, type of cargo, shipping zone, speed and some more. Very helpful tool for such analysis is list of significant ships created for specified types of ships. Mentioned lists are very effective under conditions that cover broad-spectrum new buildings and data included are credible. Uncritical taking values included in significant ships list can lead to critical errors in selection of main dimensions of a ship or its propulsion powering. For that reasons, basing on analysis, as main criteria of similarity of ship’s hull were assumed mass coefficient, block coefficient and Froude Number [2]. That procedure has significant impact at proper estimation of propulsion power. Another reliable parameter of evaluation of power seems to be relation between power and load capacity Ne/D.
EN
The paper presents the way of the fatigue life calculation of a cryogenic tank dedicated for the carriers ship application. The independent tank type C was taken into consideration. The calculation took into account a vast range of the load spectrum resulting in the ship accelerations. The stress at the most critical point of the tank was determined by means of the finite element method. The computation methods and codes used in the design of the LNG tank were presented. The number of fatigue cycles was determined by means of S-N curve. The cumulated linear damage theory was used to determine life factor.
EN
The problem of considerable difference between the first- and second-order linear Nomoto models is undertaken, not well covered in literature so far. If the former approximates the latter (better one, of a sound hydrodynamic interpretation) for some reasons, its parameters can not be easily derived from the other one, except for some specific rare cases. For such an identification purpose, we can use a simulated zigzag response and the classic procedure proposed by Nomoto in 1960. However, the first-order model thus developed yields somehow redefined constants against the original model, which lose their normal hydrodynamic (or kinematic) sense. In other words, it is very sensitive to the manoeuvre type on input, being therein the zigzag test. Therefore, the model is allowed to be only used for simulating motions essentially similar to the input zigzag. In other words, the identification procedure works like a blind curve-fitting and the first-order model (in contrast to second-order one) is inadequate for reflecting arbitrary manoeuvres, even for mild rudder as to be within 'linear' assumptions. This study examines systematically and in detail such an incompatibility of the first order model in that it presents the conversion charts from the standpoint of 10°/10° zigzag test matching. One can receive higher or lower values for the parameters of first-order model, versus the second-order one, depending on the T3/T2 ratio of the latter model.
PL
Artykuł zawiera systematyczne wyniki identyfikacji liniowego modelu Nomoto pierwszego rzędu na podstawie symulowanej próby wężowej różnych wariantów modelu drugiego rzędu. W toku analizy stwierdzono ogólną nieadekwatność (strukturalną) modelu pierwszego rzędu do symulacji dowolnych manewrów, w przeciwieństwie do modelu drugiego rzędu, nawet w granicach liniowości dynamiki statku. Wyniki identyfikacji silnie bowiem zależą od rozpatrywanego manewru.
EN
This paper deals with fuel consumption estimations relating to container ships on the basis of ship service and wave parameters. Data, on which to base estimations, was measured and recorded from a container ship during 96 months at sea. Approximating functions were calculated by the use of curve fitting techniques and regression methods, utilizing newly developed software named ndCurveMaster. The approximation function presented in this paper could have practical application for the estimation of container ship fuel consumption, while considering weather routing. In addition the study clearly shows the relationship between the fuel consumption of a container ship and the number of months since its last docking. These results may form the basis for further research in this direction.
EN
The small far infrared target of ship in surge interference is easy to have visual deviation causing the low accuracy of target positioning and the bad target identification performance. In order to improve the accuracy of far small infrared targets recognition of ship under surge interference, this paper proposed far small infrared target recognition algorithm of ship based on distributed target position estimation and DOA location in computer vision model for constructing coherent distributed source array model of far small infrared target distribution of ship. This algorithm used MUSIC algorithm for the beamforming processing of far small infrared target echo model of ship. Combined with the adaptive filtering algorithm we carried out the surge interference suppression and the estimation of central direction of arrival and angle spread of far small infrared target of ship through multidimensional spectrum peak searching algorithm, realizing the joint estimation of distance of ship target, DOA and frequency parameters, so as to realize the accurate positioning and recognition of targets. Simulation results show that using this method for the far small infrared target recognition of ship under surge interference, the spectral peak sharpness of spectral peak search of target position is high, side-lobe suppression performance is good, which shows the high accuracy of target position estimation and location, the accuracy and anti-interference performance of far small infrared target recognition of ship is good, and has superior performance.
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