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Search results for: CRITICAL MANOEUVRE
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Planning emergency manoeuvres
PublicationW artykule poruszono problem planowania manewrów ostatniej szansy i zmian planowanej trajektorii statku w przypadku nieoczekiwanych zachowań obiektów obcych. Wprowadzono dwie metody. Pierwsza z nich jest odpowiedzialna za monitorowanie parametrów obiektów obcych, szacowanie prawdopodobieństwa nieprzepisowego zachowania i aktualizację trajektorii statku własnego. Druga to narzędzie wizualizacyjne umożliwiające nawigatorowi szybki...
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Neural Manoeuvre Detection of the Tracked Target in ARPA Systems
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Data Acquisition in a Manoeuver Auto-negotiation System
PublicationTypical approach to collision avoidance systems with artificial intelligence support is that such systems assume a central communication and management point (such as e.g. VTS station), usually located on shore. This approach is, however, not applicable in case of an open water encounter. Thus, recently a new approach towards collision avoidance has been proposed, assuming that all ships in the encounter, either restricted or open...
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Equivalent standard manoeuvres for pod-driven ships
PublicationProcedures for carrying out the manoeuvring tests presented in International Maritime Organisation (IMO) resolution MSC.137(76) are based on the capabilities of ships with conventional steering-propulsion systems. Therefore they do not correspond to ships with other steering-propulsion devices, like pod drives. IMO is aware of this shortcoming and for ships with non-conventional steering and propulsion system may permit the use...
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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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Heuristic Method of Safe Manoeuvre Selection Based on Collision Threat Parameters Areas
PublicationThis paper is a continuation of papers dedicated to a radar-based CTPA (Collision Threat Parameters Area) display designed to support safe manoeuvre selection. The display visualizes all the ships in an encounter and presents situational overview from the own ship’s point of view. It calculates and displays information on unsafe or unrealistic own ship’s course & speed allowing a user to select a safe manoeuvre. So far only the...
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CRITICAL REVIEWS IN ANALYTICAL CHEMISTRY
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Application of the IMO standard manoeuvres procedure for pod-driven ships
PublicationInternational Maritime Organisation (IMO) in the resolution MSC.137(76) Standards for Ship manoeuvrability presents the manoeuvring criteria that has to be satisfied by majority of seagoing ships. Together with the criteria, procedures for carrying out the manoeuvring tests are also presented. They however do not correspond directly to ships with non-conventional steering-propulsion devices, like pod drives. IMO is aware of this...
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Determining manoeuvre detection threshold of GRNN filter in the process of tracking in marine navigational radars
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Navigational decision support system during approach manoeuvre in emergency STS transfer operation
PublicationThe paper is concerned with the problem of safe trajectory planning for approaching during emergency STS (Ship to Ship) transfer operation with oil spill. The safe trajectory means that the way points does not cross in the area of the environment with the static and dynamic obstacles and at the same time satisfies ship's stopping and speed deceleration performance. The evolutionary path planning algorithm is used to determine trajectory...
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Investigations of operational driving loads of bucket chains and manoeuvre hoisting winches on multi-bucket dredgers
PublicationArtykuł dotyczy zagadnień wstępnego projektowania siłowni pogłębiarek wieloczerpakowych. Niniejszy artykuł przedstawia wyniki badań eksploatacyjnych sześciu pogłębiarek wieloczerpakowych. Badania eksploatacyjne obejmowały pomiary parametrów charakteryzujących warunki pracy dwóch podstawowych głównych odbiorników energii mechanicznej na pogłębiarkach wieloczerpakowych a mianowicie łańcuchów czerpakowych i zespołu wciągarek manewrowych....
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Critical perspectives on media architecture
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Enhancing Availability for Critical Services
PublicationTraditional approaches to provide classes of resilient service take the physical network availability as an input and then deploy redundancy and restoration techniques at various layers, often without full knowledge of mappings between layers. This makes it hard (and often inefficient) to ensure the high availability required by critical services which are typically a small fraction of the total traffic. Here, the innovative technique...
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A Target Information Display for Visualising Collision Avoidance Manoeuvres in Various Visibility Conditions
PublicationThe paper introduces a new approach to displaying information on targets. The proposed display visualises three types of information: targets’ motion parameters (typical for target tracking), combinations of own course and speed which collide with those targets (typical for Collision Threat Parameters Area display by Lenart (1983)) and combinations of own course and speed which are not compliant with COLREGS in this case (based...
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Detection and isolation of manoeuvres in adaptive tracking filtering based on multiple model switching
PublicationW rozdziale przedstawia się model radarowego procesu pomiarowego oraz omawiaproblem modelowania trajektorii ruchu obiektów latających. Przyjęto klasę o-biektów cywilnych, których tor ruchu można opisać jak złożenie ruchu prosto-liniowego jednostajnego oraz ruchu prostoliniowego jednostajnie zmiennegolub ruchu po okręgu ze stałą prędkością (manewru). zastosowano również meto-dę estymacji nieznanej wartości wielkości sterującej,...
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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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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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Towards Agile Development of Critical Software
PublicationThe paper presents a case study aiming at collecting opinions of software en-gineers on the risks related to integration of agile practices to safety-critical software development projects. The study has been performed within the scope of our research targetting at providing critical software developers with a comprehensive solution allowing to incorporate agile practices into software development process while still being conformant...
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The upper critical field in doped MgCNi3
PublicationDyskutowany jest wpływ domieszkowania MgCNi3 na górne pole krytyczne (H_c2). H_c2 monotonicznie maleje wraz ze wzrostem koncentracji domieszki. Silniejszy wpływ widoczny w przypadku domieszkowania Fe może być tłumaczony poprzez efekt rozrywania nadprzewodzących par Coopera poprzez centra magnetyczne tworzone przez domieszki Fe.
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Weakly connected domination critical graphs
PublicationPraca dotyczy niektórych klas grafów krytycznych ze względu na liczbę dominowania słabo spójnego.
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The Analysis of Overall Ship Fuel Consumption in Acceleration Manoeuvre using Hull-Propeller-Engine Interaction Principles and Governor Features
PublicationThe problem of reduction of greenhouse gas emissions in shipping is currently addressed by many research works and related industries. There are many existing and visionary technologies and ideas, which are conceptually defined or practically realised. This goal can be achieved in different ways, and reducing fuel consumption is one of the major methods. In these circumstances, the aim of this study is to analyse the possibility...
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Evolutionary sets of safe ship trajectories with speed reduction manoeuvres within traffic separation schemes
PublicationIn the previous paper the author presented the evolutionary ship trajectory planning method designed to support Traffic Separation Schemes (TSS). This time the extensions of this method are described which allow to combine evolutionary trajectory planning with speed reduction manoeuvres. On TSS regions with higher than usual density of traffic and smaller distances between ships, the course alterations alone are not always sufficient...
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Critical section maintenance in a distributed agent system
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Agile Development of Critical Software - Can It be Justified?
PublicationThe paper introduces the problem of application of agile practices in critical software development projects. It summarizes the present state of research and identifies the need for having a ready-to-use model of being agile while still meeting the required assurance levels which could be particularly useful for small and medium sized safety-critical software companies. Then the objective and scope of a research aiming at delivering...
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Multisensor System for the Protection of Critical Infrastructure of Seaport
PublicationThere are many separated infrastructural objects within a harbor area that may be considered “critical”, such as gas and oil terminals or anchored naval vessels. Those objects require special protection, including security systems capable of monitoring both surface and underwater areas, because an intrusion into the protected area may be attempted using small surface vehicles (boats, kayaks, rafts, floating devices with weapons...
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The State and Critical Assessment of the Sharing Economy in Europe
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Sensitivity analysis of critical loads of I-columns
PublicationThe first order variation of critical buckling load of thin-walled columns with bisymmetric open cross-section due to some variations of the design variables such as: cross-section dimensions, or material characteristics is derived. The influence of the residual welding stresses is taken into account. In the numerical examples dealing with I-column the functions describing the effect of the variation of the dimensions of the flange...
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Rigorous numerics for critical orbits in the quadratic family
PublicationWe develop algorithms and techniques to compute rigorous bounds for finite pieces of orbits of the critical points, for intervals of parameter values, in the quadratic family of one-dimensional maps fa(x)=a−x2. We illustrate the effectiveness of our approach by constructing a dynamically defined partition P of the parameter interval Ω=[1.4,2] into almost 4 million subintervals, for each of which we compute to high precision the...
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Functional safety and security management in critical systems
PublicationGłównym celem referatu jest przedstawienie wybranych kwestii zarządzania bezpieczeństwem i ochroną w systemach podwyższonego ryzyka i systemach krytycznych. Zarysowuje się kilka praktycznych problemów analizy bezpieczeństwa funkcjonalnego w celu podejmowania decyzji zgodnie z normami międzynarodowymi IEC 61508 i IEC 61511. Podkreśla się, że aspekty związane z ochroną powinny być starannie rozpatrzone zarówno w fazie projektowania,...
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Application of theory of semi-Markov processes to determining distribution of probabilistic process of marine accidents resulting from colission of ships
PublicationIn this paper is presented possible application of the theory of semi-Markov processes to elaborating an eight-state model of the process of occurrence of serviceability state and unserviceability states of sea-going ships making critical manoeuvres during their entering and leaving the ports. In the analysis it was taken into account that sea-going ships are in service for a very long time t (t → ∞). The model was elaborated to...
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Determining the optimal course alteration maneouvre in a multi-target encounter situation for a given ship domain model
PublicationW artykulee przedstawiono nową deterministyczną metodę wyznaczania niezbędnego manewru kursem dla sytuacji spotkania z wieloma obiektami obcymi i dla dowolnej zadanej domeny. Jej prostota i niska złożoność obliczeniowa czynią ją dobrą alternatywą dla obecnie stosowanych metod. Główny algorytm został przedstawiony wprost, tak aby mógł być bezpośrednio zastosowany w pokładowych systemach antykolizyjnych lub w systemach VTS.
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Integrated monitoring, control and security of Critical Infrastructure Systems
PublicationModern societies have reached a point where everyday life relies heavily on desired operation of critical infrastructures, in spite of accidental failures and/or deliberate attacks. The issue of desired performance operation of CIS at high security level receives considerable attention worldwide. The pioneering generic methodologies and methods are presented in the paper project for designing systems capable of achieving these...
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Security Evaluation of IT Systems Underlying Critical Networked Infrastructures
PublicationCritical infrastructures have become highly dependent on information and communication technology (ICT). The drawback of this situation is that the consequences of disturbances of the underlying ICT networks may be serious as cascading effects can occur. This raises a high demand for security assurance, with a high importance assigned to security evaluations. In this paper we present an experiment-centric approach for the characterisation...
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Algorithms and Tools for Intelligent Control of Critical Infrastructure Systems
PublicationCritical Infrastructure Systems (CIS) are spatially distributed and of a network structure. The dynamics are nonlinear, uncertain and with several time scales. There is a variety of different objectives to be reliably met under a wide range of operational conditions. The operational conditions are influenced by the disturbance inputs, operating ranges of the CIS, faults in the sensors and actuators and abnormalities occurring in...
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Critical Reappraisal of Casagrande and Taylor Methods for Coefficient of Consolidation
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Uniform Expansivity Outside a Critical Neighborhood in the Quadratic Family
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Applying agiile practices to the development of safety-critical software
PublicationDevelopment of safety critical software is subjected to numerous restrictions and recommendations. To meet these requirements classical software development models (e.g. V-model) are usually applied. Agile methodologies, although rapidly increasing their popularity, were generally regarded as unsuitable for such projects. However, they offer potential benefits which provide a strong incentive to incorporate them into safety-critical...
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Approach to security assessment of critical infrastructures' information systems
PublicationThis study presents an approach to the security assessment of the information systems of critical infrastructures. The approach is based on the faithful reconstruction of the evaluated information system in a computer security laboratory followed by simulations of possible threats against the system. The evidence collected during the experiments, stored and organised using a proprietary system InSAW, may later be used for the creation...
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Agents in Simulation of Cyberattacks to Evaluate Security of Critical Infrastructures
PublicationIn the last years critical infrastructures have become highly dependent on the information technologies and exposed to cyberattacks. Because the effects of the attacks can be detrimental, it is crucial to comprehensively asses the security of the infrastructures' information systems. This chapter describes MAlSim - the simulator of malicious software based on software agents, developed for the needs of a testbed for critical infrastructures...
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Sensitivity analysis of critical forces of trusses with side bracing
PublicationThe present research is devoted to the study of out-of-plane buckling of trusses with elastic side bracing. Inthis paper, a sensitivity analysis of critical buckling loads of a truss due to bracing stiffness is carried out. A method based on the sensitivity analysis for the determination of the threshold bracing stiffness conditionfor full bracing of a truss is proposed. The influence lines of the unit change of the bracing stiffness...
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Approach to evaluation of time to the critical degradation of ship pipelines
PublicationIn the article an approach to the problem of estimating time to the critical degradation of ship pipelines is considered. Such an assessment would consist of six stages. The fundamental idea is to include to the estimation of time to failure of pipelines such elements like: materials that the pipelines are made, destructive physical phenomena taking place in them and applied means of protection. The result of that evaluation should...
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The critical factors of landfill fire impact on air quality
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Safety and security governance problems of critical systems and infrastructures
PublicationW artykule przedstawiono kilka problemów związanych z zarządzaniem bezpieczeństwem i ochroną informacji w systemach i infrastrukturach krytycznych.Bardzo ważne jest zidentyfikowanie i scharakteryzowanie infrastruktury krytycznej. Przedstawiono nowe wyzwania związane z łączeniem podejścia bezpieczeństwa i ochrony informacji w procesie podejmowania decyzji
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Wireless Networks as an Infrastructure for Mission-Critical Business Applications
PublicationDespite the dynamic growth of wireless network systems, their pres-ence in business-support infrastructure has been limited. In the article we provide an overview of generic corporate network architecture and examine usefulness of available wireless network solutions in such systems. Following this overview we analyze new wireless network architecture which currently undergoes standardization process - wireless mesh. It can result...
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Managing the security vulnerabilities of critical systems and hazardous plants
PublicationRozdział poświęcono aktualnym problemom zarządzania ochroną obiektów podwyższonego ryzyka jako ważnych systemów infrastruktury krytycznej. Zarządzanie odpornością na ataki takich obiektów jest oparte na ocenach ryzyka. Podkreśla się, że występują ważne instalacje i systemy wymagające specjalnej uwagi i zabezpieczeń, szczególnie systemy kontroli dostępu do sterowni i urządzeń komunikacji. Opisuje się przykładowe technologie ochrony....
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Polysaccharide-based Nanocomposites for Biomedical Applications: A Critical Review
PublicationPolysaccharides (PSA) are taking specific position among biomaterials for advanced applications in medicine. Nevertheless, poor mechanical properties is known as the main drawback of PSA, which highlights need for PSA modification. Nanocomposites PSA (NPSA) are a class of biomaterials widely used as biomedical platforms, but despite their importance and worldwide use have not been reviewed. Herein we critically reviewed application...
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Neutralising Responsibility: A Critical Analysis of an Airline’s Climate Disclosures
PublicationSustainability reporting provides companies with a medium through which they can communicate their non-financial impacts to stakeholders. The airline industry has been much at the centre of the climate change debate in recent years, which is why it is hardly surprising that airlines seek to take a proactive stance in such reporting. This study critically assesses how an airline based in the Scandinavian region constructs sustainability...
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Searching for Critical Conditions During Lifeboat Launching – Simulations
PublicationThe article describes numerical simulations of the process of lifeboat launching at the ship’s side. The research is aimed at finding the values of ship motion parameters which appear to be most dangerous for people in the lowered lifeboat due to the generated accelerations. The simplified model of ship hull motion adopted at this research stage bases on a superposition of harmonic motions with given amplitudes and periods in six...
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Heat and mass exchange in the process of condensation on critical droplets.
PublicationSformułowano model wzrostu kropli krytycznej podając równania zmiany masy i temperatury kropli. Pokazano formę zlinearyzowaną tych równań dobrze aproksymującą wzrost kropli w poblizu wymiaru krytycznego. Podano rozwiązanie układu zlinearyzowanego uzależniając zmianę temperatury od zmiany masy kropli i czasu charakterystycznego.
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Challenges in security and safety management of critical systems and infrastructures
PublicationReferat poświęcono aktualnym problemom zarządzania bezpieczeństwem systemów i infrastruktur krytycznych. Infrastruktury krytyczne szereguje się z uwzględnieniem kilku kryteriów. Zarysowuje się problematykę zarządzania podatnością obiektów podwyższonego ryzyka na działania z zewnątrz oraz zagadnienie analizy ryzyka na przykładzie systemu elektroenergetycznego. W końcowej części referatu opisuje się nowe wyzwania związane z zarządzaniem...