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This paper describes the motion characteristics and cargo handling efficiency of the Large-Scale Floating Coal Transshipment Station (LFTS). Indonesia is a main country supplying coal in the Asia-Pacific region, it is important to ensure a stable coal supply to Japan. Because the topography of the seabed near East Kalimantan Island, Indonesia’s main coal production area, is shallow, it is difficult for bulk carriers to reach the coast. Therefore, LFTS is proposed, which will be used as a relay base between coal-barging barges from land and bulk carriers offshore. By installing LFTS, improvement of coal transport efficiency is expected. In considering feasibility of the LFTS system, it is important to know the cargo handling operation rate in the target area, LFTS can load 500,000 tons of coal and the draft will fluctuate greatly depending on the loading condition of coal. Therefore, when the draft is shallow, the freeboard becomes large and resonates with long-term component of the wind load and when the draft is deep, the wave force and fluid force including the slowly varying wave drift force affect the fluctuation. Also, LFTS and bulk carrier are large-scale structures, the fluid forces acting on both affect each other, so the influence of hydrodynamic mutual interference between two floating bodies cannot be ignored. In this study, fluid analysis in consideration of the hydrodynamic mutual interference of LFTS system is conducted. And, response analysis of LFTS and a bulk carrier in irregular wave which considered compound external forces such as wave load and slow varying wave drift force, wind load, tidal current was performed. As a result, it was confirmed that the motion response of LFTS was not upset because LFTS was large. Therefore, without considering the motion response of the LFTS, the cargo handling efficiency is calculated from the response analysis results of the bulk carrier and the oceanic condition of the setting sea area. As a result, the cargo handling efficiency is satisfied in the state where bulk carrier is installed leeward of LFTS, and it was confirmed that the LFTS system could be operated satisfactorily if the installation was appropriate.

Newly developed high-strength reaction-sintered silicon carbide is an attractive material for lightweight optical mirror with two times higher bending strength than other SiC materials. The polished surface has no pore and is suited to visible region as well as infrared without CVD SiC coating. The fabrication process, with low temperature and small shrinkage, is also suited to develop large scale objects.

An innumerable number of buildings in the coastal part of the east side of Japan were devastated by the Great East Japan Earthquake and Tsunami. Medical institutions also suffered the damage caused by tsunami, and the function to carry out the medical act has been spoiled. And the disabled concentrated on the medical institution which avoided tsunami damage. Under such circumstances, assistance from the water area began three days after the earthquake disaster, and much support supplies reached the stricken area. It was revealed that the support from the water area including the river was extremely effective against the stricken area. And then, the Tokyo Inland Earthquake disaster was assumed, floating medical support system installed in the quay of Arakawa River in Tokyo was proposed. Floating medical support system is movable; furthermore, it is built in the structural system of having very high isolation characteristics. Therefore, feasibility study such as selection of suitable setting position of this floating structure on Arakawa River, floor planning and flow planning at the time of always and a disaster, facilities and storage of various material, structural strength of the floating base, and the effects of disaster risk reduction was carried out about floating medical support system.

In the development of large-scale astronomical telescopes, certain new ceramics such as Silicon Carbides (SiC) and glass-ceramics (Zerodur) are applied for primary mirrors. However, the surface finishing of these ceramic mirrors is very time consuming by traditional polishing processes. In this study, a highly efficient process called ELID (Electrolytic In-process Dressing) grinding was conducted to grind ceramics for lightweight mirrors (CVD-SiC, Sintered-SiC, Zerodur). The dependence of subsurface properties on grinding process parameters was investigated. The subsurface damages on the ground surfaces were observed by AFM. The results demonstrated that crack-free surface could be obtained for CVD-SiC and Zerodur using cast iron bond diamond wheel with grain size of 4µm. The total depth of cut needed was found to be between 13 and 20µm. It was difficult to eliminate the subsurface damages generated on the ground surface of Sintered SiC, even though the depth of cut was as small as 0.1µm.

A plate structural system has great possibilities for construction of oceanic structures, especially, floating structures on the sea, which can be applied to a floating artificial base so as to construct floating airport, floating city, IT industrial base, etc.The purpose of this study is to propose an easy calculation method for natural frequency analysis of elastic plate as coupled vibration of plate and water. In the dynamic analysis of floating plate, most of research subjects were on wave response related until now, and papers focused on natural frequency analysis corresponding to response function are hardly found. In addition, experimental approaches by the model testing can't be found. The fluid analysis requires special knowledge with complicated procedure of calculation. It is known that added mass depends on frequency, and in case of vibration problem, it depends on both shape of vibration mode and frequency.Using nine testing models of plate existing on water, modal experiment was carried out as plate-water coupled vibration. The feature of added mass distribution were grasped by identifying natural frequency corresponding to vibration mode order, and through the study a practical estimation method of added mass which can be combined to structural mass, is presented. The validity of this method has been verified by the demonstration through comparisons.

Large scale floating structures, such as floating airport and amusement park having two dimensional expanse in horizontal direction, which structural concept can be considered as plate-type structural system. This structural system has a great deal of potential to be applied to oceanic structures like a artificial ground. This practical fabrication will be done by a combination of units. The hydroelastic interaction problem and structural design have attracted the attention of researchers and structural engineers. This paper presents consideration and conclusion through the numerical calculation results of the natural frequency studied under the various supporting conditions by developed computer program. The theoretical development is obtained by a way of combination of finite element method (FEM) and boundary integral equation method (BIEM). As to natural frequency analysis of oceanic structures based on the fluid-structure interaction, in general, there is an assumption to make it possible by estimating properly the added mass of the structure surrounding by water. The added mass of floating plate obtained by BIEM is modified and transformed into mass matrix of plate in FEM analysis. Herein, FEM analysis is based on the bending vibration assumption.