Floating offshore wind turbines are complex dynamical systems. The use of numerical models is an essential tool for the prediction of the fatigue life, ultimate loads and controller design. The simultaneous wind and wave loading on a non-stationary foundation with a flexible tower makes the development of numerical models difficult, the validation of these numerical models is a challenging task as the floating offshore wind turbine system is expensive and the testing of these may cause loss of the system. The validation of these numerical models is often made on scaled models of the floating offshore wind turbines, which are tested in scaled environmental conditions. In this study, an experimental validation of two numerical models for a floating offshore wind turbines will be conducted. The scaled model is a 1:35 Froude scaled 5 MW offshore wind turbine mounted on a tension-leg platform. The two numerical models are aero-hydro-servo-elastic models. The numerical models are a theoretical model developed in a MATLAB/Simulink environment by the authors, while the other model is developed in the turbine simulation tool FAST. A comparison between the numerical models and the experimental dynamics shows good agreement. Though some effects such as the periodic loading from rotor show a complexity, which is difficult to capture.

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Abstract-The increasing market of mobile phones, has increased the need for electricity to power mobile phones, as well. This paper investigates the possibilities to charge a mobile phone by harvesting energy from the surroundings. Some technologies are better suited for this purpose than others. Through previous analyses solar cells and electromagnetic generator were found to be the most suitable solution. This paper will give a basic description of the operating conditions of solar cells and an electromagnetic generator. There will also be a short view on the electrical circuit needed for implementing the harvested energy. Calculations regarding the power produced by amorphous silicon solar cells in both sun light and light from different light emitting sources will be examined. Furthermore calculations of the spring for the electromagnetic generator and the power produced by this device will be examined. Through experiments and data processing the energy delivered by the solar cells and the electromagnetic generator is investigated, furthermore an experiment regarding the movement of the phone will be executed.

The demand for energy in Southeast Asia and the Pacific region has resulted in vast growth in gas exploration across the continent of Australia. With the approval for a number of liquefied natural gas (LNG) export facilities across the Australian seaboard, Arup Australasia has put its multi-disciplinary capabilities to full use in the delivery of a number of LNG jetties in Gladstone, Queensland in a design and construct collaboration with the contractor John Holland Group (JHG). This paper presents the design and construction of the dolphin structures, which were the result of close collaboration between JHG and Arup. The goal of this paper is to describe the importance of early constructability considerations and the complex interface between maritime, geotechnical and structural disciplines. The paper outlines the inputs and the consideration of both berthing and mooring dolphins designed to accommodate berthing and mooring of vessels of up to 220 000 m3 capacity. The approach of the paper is to describe the design solution in broad terms and selected key aspects in detail.

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