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Search results for: WEATHER ROUTING, WEATHER HAZARD AVOIDANCE, MULTICRITERIA WEATHER ROUTING, WEATHER CONDITION, SPEA ALGORITHM, HYBRID PROPULSIONS, MOTOR-DRIVEN SHIP, SHIP SAFETY MEASURE
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Evolutionary Sets Of Safe Ship Trajectories: A New Approach To Collision Avoidance
PublicationThe paper introduces a new method of solving multi-ship encounter situations for both open waters and restricted water regions. The method, called evolutionary sets of safe trajectories combines some of the assumptions of game theory with evolutionary programming and aims to find optimal set of safe trajectories of all ships involved in an encounter situation. In a two-ship encounter situation it enables the operator of an on-board...
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On the estimation of the design loads on container stacks due to excessive acceleration in adverse weather conditions
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Geomagnetic Storms and Substorms as Space Weather I nfluence on Atmospheric Electric Field Variations
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Ship domain applied to determining distances for collision avoidance manoeuvres in give-way situations
PublicationShip domain is often used in marine navigation and marine traffic engineering as a safety condition. The basic idea behind those applications is that an encounter of two or more ships can be considered safe if neither of ship domains is intruded by other ships. Research utilising this approach has been documented in numerous works, including publications on optimising collision avoidance manoeuvres performed to fulfil domain-based...
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The Development of a Combined Method to Quickly Assess Ship Speed and Fuel Consumption at Different Powertrain Load and Sea Conditions
PublicationDecision support systems (DSS) recently have been increasingly in use during ships operation. They require realistic input data regarding different aspects of navigation. To address the optimal weather routing of a ship, which is one of the most promising field of DSS application, it is necessary to accurately predict an actually attainable speed of a ship and corresponding fuel consumption at given loading conditions and predicted...
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INDICES FOR ASSESSING POTENTIAL ENVIRONMENTAL HAZARD FROM FUTURE SHIP SCRAPPING PROCESS, DETERMINABLE IN SHIP DESIGN STAGE
PublicationThis paper shortly presents the issue of utilization of ships after their withdrawal from service. Information on number of floating units liquidated in previous years was presented. Hazards to the environment , health and life of workers employed in the Far East ship scrapping yards operating on the beaches, were indicated. Then, the most important rules which have to make the ship recycling process safe were referred to. This...
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A Ship Domain-Based Method of Determining Action Distances for Evasive Manoeuvres in Stand-On Situations
PublicationA ship encounter can be considered safe if neither of ships’ domains (defined areas around ships) is intruded by other ships. Published research on this includes optimising collision avoidancemanoeuvres fulfilling domain-based safety conditions.However, until recently there was no method, using ship’s domain to determine exact moment when a particular collision avoidance manoeuvre can still be successfully performed. The authors...
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The Influence of Weather Anomalies on Mercury Cycling in the Marine Coastal Zone of the Southern Baltic—Future Perspective
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Multi-source-supplied parallel hybrid propulsion of the inland passenger ship STA.H. Research work on energy efficiency of a hybrid propulsion system operating in the electric motor drive mode
PublicationIn the Faculty of Ocean Engineering and Ship Technology, Gdansk University of Technology, design has recently been developed of a small inland ship with hybrid propulsion and supply system. The ship will be propelled by a specially designed so called parallel hybrid propulsion system. The work was aimed at carrying out the energy efficiency analysis of a hybrid propulsion system operating in the electric motor drive mode and at...
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Taxonomy of Schemes for Resilient Routing
PublicationThis chapter provides a taxonomy of schemes for resilient routing followed by a discussion of their application to contemporary architectures of communication networks. In particular, a general classification of schemes for resilient routing is first presented followed by a description of the reference schemes for IP networks. The chapter in its later part focuses on the representative techniques of resilient routing for a multi-domain...
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Weather Conditions, Orchard Age and Nitrogen Fertilization Influences Yield and Quality of ‘Łutówka’ Sour Cherry Fruit
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Hybrid System for Ship-Aided Design Automation
PublicationA hybrid support system for ship design based on the methodology of CBR with some artificial intelligence tools such as expert system Exsys Developer along with fuzzy logic, relational Access database and artificial neural network with backward propagation of errors.
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USING ARTIFICIAL NEURAL NETWORKS FOR PREDICTING SHIP FUEL CONSUMPTION
PublicationIn marine vessel operations, fuel costs are major operating costs which affect the overall profitability of the maritime transport industry. The effective enhancement of using ship fuel will increase ship operation efficiency. Since ship fuel consumption depends on different factors, such as weather, cruising condition, cargo load, and engine condition, it is difficult to assess the fuel consumption pattern for various types...
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Disaster-Resilient Routing Schemes for Regional Failures
PublicationLarge-scale natural disasters can have a profound effect on the telecommunication services in the affected geographical area. Hence, it is important to develop routing approaches that may help in circumventing damaged regional areas of a network. This prompted the development of geographically diverse routing schemes and also of disaster-risk aware routing schemes. A minimum-cost geodiverse routing, where a minimum geographical...
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Resilient Routing in Communication Networks
PublicationThis important text/reference addresses the latest issues in end-to-end resilient routing in communication networks. The work highlights the main causes of failures of network nodes and links, and presents an overview of resilient routing mechanisms, covering issues related to the Future Internet (FI), wireless mesh networks (WMNs), and vehicular ad-hoc networks (VANETs). For each of these network architectures, a selection of...
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Collision‐Aware Routing Using Multi‐Objective Seagull Optimization Algorithm for WSN‐Based IoT
PublicationIn recent trends, wireless sensor networks (WSNs) have become popular because of their cost, simple structure, reliability, and developments in the communication field. The Internet of Things (IoT) refers to the interconnection of everyday objects and sharing of information through the Internet. Congestion in networks leads to transmission delays and packet loss and causes wastage of time and energy on recovery. The routing protocols...
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HYBRID ENERGY SYSTEM FOR A CLASSIC SHIP POWER PLANT
PublicationThe article presents a brief overview of hybrid energy systems used on ships. The area of their application is outlined. The benefits of using such systems are also indicated. Then, the classic ship power plant is defined. The most important part of the article is a proposal how to modify a classic engine room by using a hybrid energy system. The idea is: to accumulate a part of electricity in areas where it is allowed to burn...
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APPLICATION OF REDUNDANCY IN SHIP POWER PLANTS OF OFFSHORE VESSEL
PublicationPower and propulsion systems of offshore units must be of a very high level of reliability. The loss of ability to perform functions of their components causes generally to very high economic losses, which may be increased by unused the weather window resulting to postponing the planned offshore operations. To ensure carrying out so expensive offshore operations in the most reliable way, various types of redundancies are built-in...
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Survivability function - a measure of disaster-based routing performance.
PublicationZnaczenie przeżywalności sieci transmisji danych systematycznie rośnie, ponieważ awaria pojedynczego elementu może dotknąć miliony użytkowników na dużym obszarze. Zdefiniowano funkcję przeżywalności: prawdopodobieństwo realizacji określonego procentu strumieni użytkowników po awarii oraz atrybuty przeżywalności. Celem pracy było zbadanie wpływu protokołów doboru tras architektury TC/IP na funkcję i atrybuty przeżywalności. Pracę...
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Distribution of oil spill response capability through considering probable incident, environmental sensitivity and geographical weather in Vietnamese waters
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Calculation of silicon cell temperature of loaded photovoltaic module based on thermal coefficients for different weather conditions of Northern Poland
PublicationWydajność obciążonego modułu fotowoltaicznego zależy silnie od natężenia promieniowania słonecznego, temperatury otoczenia, prędkości wiatru i temperatury wewnętrznej składowych ogniw fotowoltaicznych. Sprawność konwersji fotowoltaicznej spada istotnie wraz z e wzrostem temperatury złącza p-n. Pomiar tej temperatury jest niemożliwy i oblicza się ją w oparciu o mierzoną wartość temperatury przedniej lub tylnej powierzchni modułu...
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Assessment of damage to trees in the Herby Forestry District caused by glazed frosts and snow during severe weather in January 2010
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A probabilistic-driven framework for enhanced corrosion estimation of ship structural components
PublicationThe work proposes a probabilistic-driven framework for enhanced corrosion estimation of ship structural components using Bayesian inference and limited measurement data. The new approach for modelling measurement uncertainty is proposed based on the results of previous corrosion tests that incorporate the non-uniform character of the corroded surface of structural components. The proposed framework's basic features are outlined,...
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A Method of Assessment of the Liquid Sloshing Impact on Ship Transverse Stability
PublicationLiquid sloshing phenomenon taking place in partly filled ships? tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. The set of numerical simulations of liquid...
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Routing equal-size messages on a slotted ring
PublicationAnalizujemy problem routingu wiadomości w sieci slotted ring, biorąc pod uwagę dwa kryteria optymalizacyjne: długość uszeregowania oraz liczbę 'cykli' pracy sieci. Optymalny routing dla wiadomości o rozmiarze k jest silnie NP-trudny, natomiast dla k=q, gdzie q jest rozmiarem sieci, można obliczyć w czsie O(n^2log n) dla pierwszego kryterium. Podajemy również algorytm o czasie działania O(nlog n) oraz o stałym współczynniku dobroci....
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The sensitivity of bacteria to heavy metals in presence of mineral ship motor oil in coastal marine sediments and waters.
PublicationThe sensitivity of bacteria, isolated from coastal marine sediments and waters of Sopot beach, Gdańsk Bay (Poland), to heavy metals in the presence of mineral ship motor oil were studied. All isolated heterotrophic bacteria were resistant to the 0.1 mM lead concentration occurring in the environment. Metal resistance of bacteria isolated from coastal water was strongly related to mineral ship motor oil concentration. At 0.1% mineral...
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Traffic Type Influence on Performance of OSPF QoS Routing
PublicationFeasibility studies with QoS routing proved that the network traffic type has influence on routing performance. In this work influence of self-similar traffic for network with DiffServ architecture and OSPF QoS routing has been verified. Analysis has been done for three traffic classes. Multiplexed ON-OFF model was used for self-similar traffic generation. Comparison of simulation results were presented using both relative and...
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Simulation model for evaluation of QOS dynamic routing
PublicationCurrent informational networks use a large variety of technologies to support data exchange. Most of them are focused on IP protocol and include mechanisms which by definition should supply demanded QoS. One of those mechanisms is efficient path calculation - routing. Traffic offered to the network can change very rapidly in short term. Routing should support such traffic changes and all the time calculate valid paths in terms...
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Traffic Type Influence on Performance of OSPF QoS Routing
PublicationFeasibility studies with QoS routing proved that the network traffic type has influence on routing performance. In this work influence of self-similar traffic for network with DiffServ architecture and OSPF QoS routing has been verified. Analysis has been done for three traffic classes. Multiplexed On-Off model was used for self-similar traffic generation. Comparison of simulation results was presented using both relative and non-relative...
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The Weather as an Indicator for Decision-Making Support Systems Regarding the Control of Cutworms in Beets and Cereal Leaf Beetles in Cereals and Their Adoption in Farming Practice
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Hybrid Expert System for Computer-Aided Design of Ship Thruster Subsystems
PublicationThe article presents an expert system supporting the design of ship's power subsystems, in particular the thruster subsystem. The proposed hybrid expert system uses the results of simulation tests as the additional source of knowledge. The results of system operation are collated in a report which can be used as part of ship design description. The work oriented on developing the expert system is the continuation of the research...
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The Impact of Sloshing Liquids on Ship Stability for Various Dimensions of Partly Filled Tanks
PublicationLiquid sloshing phenomenon taking place in partly filled ships' tanks directly affects the stability of a vessel. However, only static calculations are carried out onboard ships nowadays and static transfer of liquid weight is taken into account in the course of routine stability calculation. The paper is focused on a dynamic heeling moment due to liquid sloshing in tanks onboard ships. A number of numerical simulations of liquid...
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ISSUE OF MAKING DECISIONS WITH REGARD TO SHIP TRAFFIC SAFETY IN DIFFERENT SITUATIONS AT SEA
PublicationThe paper refers to the possibilities of making operational decisions that would enable to ensure safety to a ship in the event of application of the statistical decision theory with consideration of an expected value of consequences as a criterion for making such a decision. General description includes conditions for carrying out transportation tasks by ships and it has been shown that following this description it is possible...
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Influence of Self-Similar Traffic Type on Performance of QoS Routing Algorithms
PublicationProviding a Quality of Services (QoS) into current telecommunication networks based on packet technology is a big challenge nowadays. Network operators have to support a number of new services like voice or video which generate new type of traffic. This traffic serviced with QoS in consequence requires access to appropriate network resources. Additionally, new traffic type is mixed with older one, like best-effort. Analysis of...
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Automation of ship and control
PublicationSummaryThe article presents the problem of automation of ship and control. This paper will discuss the basic tasks of the track ship control, collision avoidance and automatic dynamic positioning. The following subjects will be presented: the general structure of the ship's control, methods and control algorithms for the above mentioned tasks..StreszczenieArtykuł przedstawia zagadnienia automatyzacji i sterowania statkiem. W pracy...
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Areas of Updraft Air Motion in an Idealised Weather Research and Forecasting Model Simulation of Atmospheric Boundary Layer Response to Different Floe Size Distributions
PublicationPresented dataset is part of a numerical modelling study focusing on the analysis of the influence of sea ice floe size distribution (FSD) on the horizontal and vertical structure of convection in the atmosphere. The total area and spatial arrangement of the up-drafts indicates that the FSD affects the total moisture content and the values of area averaged turbulent fluxes in the model domain. In fact, while convective updrafts...
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A Method of Risk and Safety Assessment During the Ship Salvage Using the Hazard, Release and Consequence Analysis
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A multiparameter simulation-driven analysis of ship turning trajectory concerning a required number of irregular wave realizations
PublicationIn times of progressive automation of the marine industry, accurate modeling of ship maneuvers is of utmost importance to all parties involved in maritime transportation. Despite the existence of modern collisionavoidance algorithms using 6DOF motion models to predict ship trajectories in waves, the impact of stochastic realization of irregular waves is usually neglected and remains under-investigated. Therefore, herein, this phenomenon...
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Routing decisions independent of queuing delays in broadband leo networks
PublicationThis paper presents an analysis of queuing and propagation delays of Inter-Satellite Links (ISLs) in broadband Low-Earth Orbit (LEO) satellite networks. It is shown that queuing delays are negligible in all reasonable working conditions of the broadband ISL network. This fact makes it possible to simplify the routing protocols in such networks and permits using already known multi-commodity flow solutions for routing. The performance...
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Methods for physical impairment constrained routing with selected protection in all-optical networks
PublicationIn this paper, we investigate the problem of survivable all-optical routing in WDM networks with physical impairments. One of the recent key issues in survivable optical network design refers to maximization of the ratio of routeable demands while keeping the overall network cost low. In WDM networks, this goal can be achieved by routing as many demands in all-optical way as possible. Based on the latest technical trends driven...
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TOTAL SHIP OPERABILITY – REVIEW, CONCEPT AND CRITERIA
PublicationThe ship operability can be understood and analysed in different manners, and its quality is described using different indexes by different authors. Practically, there is no general and widely accepted description of total ship operability in the literature, nor in the rules of classification societies, which would include both seakeeping and manoeuvrability characteristics of a ship, and simultaneously take into account all ship...
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Supporting development of the smart ship technology by CFD simulation of ship behavior in close to real operational conditions
PublicationThe shipping industry is at the milestone of technological development – autonomous ships. Involving smart technologies accelerates development of green and safe shipping. Also IMO regulations, especially EEDI en-hanced application of new technologies. Meeting economic and ecological requirements future ships need to be designed with respect to increased reliability and operational performance. Design process of ships may be improved...
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A Simulative Comparison of Ship Domains and Their Polygonal Approximations
PublicationThe paper investigates the impact of a precise ship domain shape on the size of collision avoidance manoeuvres. The considered collision avoidance manoeuvres include both course and speed alterations. Various ship domains are compared with their polygonal approximations, which vary in the number of points of a domain contour and placement of these points. The best of all considered approximations is determined in the course of...
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Inverse Flood Routing Using Simplified Flow Equations
PublicationThe paper considers the problem of inverse flood routing in reservoir operation strategy. The aim of the work is to investigate the possibility of determining the hydrograph at the upstream end based on the hydrograph required at the downstream end using simplified open channel flow models. To accomplish this, the linear kinematic wave equation, the diffusive wave equation and the linear Muskingum equation are considered. To achieve...
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Simulation Environment in Python for Ship Encounter Situations
PublicationTo assess the risk of collision in radar navigation distance-based safety measures such as Distance at the Closest Point of Approach and Time to the Closest Point of Approach are most commonly used. Also Bow Crossing Range and Bow Crossing Time measures are good complement to the picture of the meeting situation. When ship safety domain is considered then Degree of Domain Violation and Time to Domain Violation can be applied. This...
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Towards a Method Evaluating Control Actions in STPA-Based Model of Ship-Ship Collision Avoidance Process
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Toward a Method Evaluating Control Actions in STPA-Based Model of Ship-Ship Collision Avoidance Process
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Towards Safety Case Integration with Hazard Analysis for Medical Devices
PublicationSafety case is one of system safety lifecycle products and should be consistent with other lifecycle products like hazard analysis results. In this paper we present a method of safety case integration with hazard tables based on the use of parametrized argument patterns. We describe a hazard table metamodel, a safety argument pattern and a mechanism of pattern instantiation using a linking table which represents references to system...
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Approach Manoeuvre During Emergency Ship-to-Ship Transfer Operation with Oil Spill
PublicationOne of the major activities during Ship to Ship (STS) transfer operation at sea is to safe approach the Ship to be Lightered (SBL) which moves on a constant heading with slow speed or drifting. In the paper described the manoeuvring problem for approaching during emergency STS transfer operation with oil spill. The approach manoeuvre is considered as a sequence of navigation manoeuvres in specific navigational environment with...
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A multiparameter simulation-driven analysis of ship response when turning concerning a required number of irregular wave realizations
PublicationThe growing implementation of Decision Support Systems on modern ships, digital-twin technology, and the introduction of autonomous vessels cause the marine industry to seek accurate modeling of vessel response. Despite the contemporary 6DOF models can be used to predict ship motions in irregular waves, the impact of their stochastic realization is usually neglected and remains under-investigated. Especially in the case of turning, differences...