OPERATIONAL BEHAVIOUR OF AN OFFSHORE MULTIPURPOSE SUPPORT VESSEL IN THE EASTERN MEDITERRANEAN SEA

The objective of this work is to analyse the operational behaviour of an offshore multipurpose support vessel designed to operate in the Eastern Mediterranean Sea. First, the seakeeping analysis is performed in a regular wave condition for different heading angles estimating heave and pitch motions through the strip theory. After that, the effects of the vertical acceleration on the bow, occurrence of slamming or hydrodynamic impact of the hull on the surface of the water; wetted deck, occurrence or invasion of water on the deck of the vessel and propeller emersion, motion sickness and wave-induced additional resistance are analysed. The present analysis is extended in an irregular sea condition, and the estimated seakeeping criteria are compared to the acceptable levels. In defining the most suitable operational mode of the offshore support vessels, multi-criteria decision techniques and probabilistic approach are employed to perform an adequate evaluation of the seakeeping performance accounting for different hazardous events through the service life.

Suitability of natural rocks as materials for cutting tools

This study presents an investigation of the usability and suitability of natural rocks as cutting tool materials. Therefore, indexable inserts are manufactured from eight different rocks and two mono minerals in this study and are used for turning of an aluminium alloy. Besides that, a characterization of the rock properties is performed. The wear of the rock tools and the surface roughness of the workpiece generated by the tools are used to evaluate their operational behaviour. Subsequently, the rock properties and the corresponding operational behaviour are used to assess the suitability of the rocks as cutting tool material. The results show that rock inserts can be used as cutting material for the turning of an aluminium alloy showing a width of wear marks between 83 and 1665 µm at the flank face after a cutting length of 500 m depending on the rock used. Furthermore, it is shown that rock tools are able to achieve surface roughness values which are comparable to those obtainable by using a conventional cemented carbide insert. The study shows that natural rocks can generally be used as alternative cutting material for the turning of aluminium. In addition a possible way for a systematic investigation and assessment of the suitability of natural rocks as cutting tool materials is presented, the relevance of the rock properties for the operational behaviour of the rock inserts is described and relevant future research topics concerning the use of rocks as cutting tool material are identified. Article highlights Demonstrating the possibility to use natural rocks as alternative environmentally friendly cutting tool material. Evaluation of operational behaviour and wear mechanisms of rock tools in turning aluminium. Identification of rock properties relevant for the operational behaviour of rock inserts.

Consumption Optimised Manoeuvring Method for Ship Automation

The paper presents a method for gradual automation of ship manoeuvring, focusing on ships already in service. The approach involves the expert knowledge of both nautical officers and ship engineers to optimise the operational behaviour and reduce fuel consumption and emissions. Detailed models of dynamic ship motion and engine processes form the basis of various software tools to assist the manual planning and execution of effective voyages. The results of a study in ship handling simulator show that the manual manoeuvring efficiency of experienced nautical officers has also been significantly increased by these assistance instruments. With regard to automatic shipping, the generated optimal plan is transferred to the automatic control system as a target trajectory. Based on a simplified motion model, the controller structure with feed-forward and feedback modules was developed to realise velocity, heading and track control. Results of controller application in simulator tests with and without wind disturbances are presented. In addition, the paper describes the development of necessary framework conditions for safety-critical areas for the application of automatically controlled manoeuvres in today’s practice with the so-called nautical algorithms according to the research project GALILEOnautic 2.

Internet of Things (Future of Inventions on Artificial Intelligence)

The Inclination of world towards Internet of Things (IOT) is the future of each biotic and abiotic things in world. As the IOT will transform into enormous networks of connected devices transmitting data of their functioning with the help of internet, artificial intelligence & data sensor to transform them into intelligent virtual objects. The aim of IOT is to provide more comfortable & efficient life the consumer, by gathering operational behaviour of an object to track down its effect. In sneak peak of this, present study portrays the future opportunity of IOT concept by systematic research paper of scholar & the five popular IOT devices launched in world and their functioning.

Operational Behaviour of an Offshore Multipurpose Support Vessel in the Eastern Mediterranean Sea

The objective of this work is to analyse the operational behaviour of an offshore multipurpose support vessel designed to operate in the Eastern Mediterranean Sea. First, the seakeeping analysis is performed in a regular wave condition for different heading angles estimating heave and pitch motions through the strip theory. After that, the effects of the vertical acceleration on the bow, occurrence of slamming or hydrodynamic impact of the hull on the surface of the water; wetted deck, occurrence or invasion of water on the deck of the vessel and propeller emersion, motion sickness and wave-induced additional resistance are analysed. The present analysis is extended in an irregular sea condition, and the estimated seakeeping criteria are compared to the acceptable levels. In defining the most suitable operational mode of the offshore support vessels, multi-criteria decision techniques and probabilistic approach are employed to perform an adequate evaluation of the seakeeping performance accounting for different hazardous events through the service life.

A Methodology for the Application of Virtual Evaluation Methods within the Design Process of Cold Forged Steel Pinions

Gears are essential machine elements in the drivetrain and transmission technology. The operational behaviour of a gear pairing is influenced by the design of the gear kinematics as well as the component properties. With regard to an improvement of performance and service life, the targeted modification of tooth geometry and component properties offers a promising approach. Thus, the achievable geometric and mechanical component properties are influenced by the manufacturing process, which must be taken into account in the design process. The application of virtual evaluation methods is suitable for this purpose. For the manufacturing of steel gears, cold forging provides the potential of achieving beneficial mechanical properties in a highly productive process. Major challenges for the industrial application are the short service life of the cost- intensive tools and the low geometric accuracy in comparison to machining processes. Within this study the design of the tooth geometry as well as the associated forming tool are investigated. The aim is to derive recommendations regarding an optimization of the resulting component properties and operational behaviour.