Journal of Maritime Technology and Environment 2010 VOL1

The purpose of this article is to numerically investigate the dynamic response of a heavy water nuclear storage vessel subjected to an impact with high speed debris (pipe fragment). The pipe fragment has a mass of 31 kg. There were employed 5 different simulation scenarios, where the projectile was supposed to have speeds from 10 to 50 m/sec. The used simulation code was ANSYS/LS-DYNA, taking advantage of its explicit dynamics facilities and capability to model a solid/fluid interface. The impact was studied for the vessel wall which was simulated involving Shell 163 type finite elements and also the effect of the fluid on response was considered, the vessel being considered filled with radioactive heavy water at atmospheric pressure.

As presented in the title, the present paper is a sequel of the previous one, dedicated to the general study of the engine dynamic system. For this engine we developed a structural and kinematic model. The main purpose is now the study of the marine engine dynamic behaviour, including the system response, stress limits, the influence of one missfiring cylinder, system resonance and counteracting shafting torsional vibrations. The main conclusions have been presented in Part I

Computational methods to predict the vibration of an internal combustion engine have become more important as demands for matching the lighter weight with low vibration levels and for reducing the development period have been increasing. The former studies of engine vibration are categorized into two groups. One deals with structural vibration (elastic vibration) in relatively higher frequencies. The other deals with kinematic vibration (rigid body motion) in low frequencies. Recently, it is becoming more important to analyze structural and kinematic coupled vibration in middle range frequencies. In this study, we developed an engine vibration analysis system for a computer aided design software, which can comprehensively analyze structural and kinematic coupled vibration in a wide range. A new formulation using a local observer frame and eigenmodes was proposed to efficiently calculate the structural and kinematic coupled vibration of the moving elastic body. In addition, some types of force elements were developed to express the transmitting force from a body to another body or the boundary conditions. The developed program was applied to a real engine model and verified by experiment under running conditions

The arc-fault circuit interrupter (AFCI) is emerging as a new device in the US National Electrical Code (NEC) and in residential installations to enhance electrical safety. New technology generally fosters questions and concerns about the workings and application of the technology and this article will address some of the most frequently asked questions surrounding AFCI: • How does the AFCI work? and, • What is the state of the potential application of AFCIs in ship electric systems? This article addressees both questions.

Approximately 90 per cent of global trade is realized via ships and seaways: a world without shipping is therefore unimaginable. Consequently, hazards and accidents in shipping have negative effects on the world-wide economy and have to be avoided by adequate safety related measures. As the United Nations specialised agency in the maritime field, the International Maritime Organisation (IMO) is responsible for improving maritime safety and preventing pollution from ships. One of the most important regulatory measures to achieve these aims is the International Safety Management Code. Additionally, based on IMO conventions and performance standards as i.a. for Integrated Navigation and Integrated Bridge Systems (INS/IBS), many new devices and sophisticated systems are these days installed onboard to support the bridge team and the pilot in handling a ship safely and in managing operational risks. However, accidents still occur and further improvement of risk management is needed. This paper deals with investigations into the application of simulation techniques to enhance onboard operational risk management. A concept for a real-time simulation-based tool using an innovative combination of mandatory technical and navigational equipment will be introduced, and a sample for applying such a module for the purpose of collision avoidance is described.

Irrespective of a variety of stressful factors, psychologists study those consequences, which they cause on physiological, psychological and behavior levels. With rare exceptions, these consequences are negative. There are emotional shifts, the sphere is deformed motivation, the course of processes of recognition and thinking changes, the impellent and speech behavior is broken. There are bases to assert, that the influence of particularly strong disorganization on human activity by the ship is made with emotional stresses achieved degrees frustration. The force frustrations are the ones that are capable of breaking any other mental processes. Moreover, frustrations impose on man certain stereotyped ways „of an emergency output" from an extreme situation adequate to the form of the displayed frustration Presumably, the optimization of the mental condition and behavior of each crew member in extreme situations should provide the appropriate psychological preparation. Otherwise, there is nothing to hope that the individual, staying in a stressful condition, will work rationally, vigorously, quickly, with perseverance.

The superficial layers obtained using electrical discharge technology in impulses is part of surfaces engineering domain. In this paper we analyze phase quality using X-ray diffraction on superficial layers after the sparkling process with wolfram, titanium and aluminum and graphite electrode. The phase quality analyses through X-ray diffraction for deposition layers with electrical discharge method using wolfram, titanium, aluminum and graphite electrodes on non alloy steel samples suppose the obtain and interpretation of diffraction graphics.

The experimental research was made on superficial layers laid-down through electrical sparking on the steel carbon OL 37 probes, the used electrode being made from a corrosion resistant material (Nickel). The corrosion resistance of the obtained experimental layers was determined through gravimetrical method. The superficial layers subjected to the corrosion agent (see water) where analysed through optical microscopy, using the computers QX3 Intel Play microscope and through atomic force microscopy.