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Nowaday, a study on saving energy as well as reducing resistance acting on a ship is important in maritime transportation. In this study, the authors present a study on reducing air resistance acting on a ship by using interaction effects between the hull and an accommodation. At first, air resistances acting on a hull and an accommodation of the ship are investigated by a commercial Computation Fluid Dynamic (CFD) code. Then, CFD results are compared with those of experimental results to validate the accuracy of the CFD. Secondly, air resistances acting on the ship with an accommodation on its deck are computed to obtain air resistances acting on the whole ships, on the hull and on accommodation. The results demonstrate that the interaction effects between the hull and its accommodation house be also shown how to reduce the total air resistance by using interaction effects between the hull and an accommodation house. The results can be applied in reducing the total resistances acting on a ship.

Patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) can develop multiple border-zone infarcts due to hypotension, hypovolemia, or surgery. We report the case of a 41-year-old woman with CADASIL who developed multiple border-zone infarcts due to influenza A virus infection. The patient had no apparent history or episode of stroke or altered consciousness following the onset of respiratory symptoms, which were due to the influenza A infection. Diffusion-weighted magnetic resonance images of the brain showed multiple acute-phase infarcts in border-zone areas of both cerebral hemispheres and the corpus callosum; fluid-attenuated inversion-recovery magnetic resonance images showed increased signal in the subcortical areas of both temporal poles. Gene analysis identified a heterozygous mutation c.160C>T in exon 2 of the NOTCH3 gene (p.Arg54Cys). A diagnosis of CADASIL was established. Our case demonstrates that infectious conditions such as influenza A can trigger multiple border-zone infarctions in patients with CADASIL.

This paper presents a study on use of a Computational Fluid Dynamics (CFD) code to investigate the effects of side guard on aerodynamic performances of a Wood Chip Carrier (WCC). The WCC hull equipped with cranes and hoppers on its deck has been used as a reference model. Firstly, applying CFD to compute the aerodynamic performances of the original hull. Then, evaluating effects of hull shape as well as the accommodation, cranes and hoppers on aerodynamic performances and wind drag acting on the original ship. The obtained CFD results of wind drag acting on the original WCC have been compared with experimental data to validate the accuracy of the CFD. Secondly, aerodynamic performances of the WCC with the side guards have been computed by the CFD. And, the effects of the side guards on aerodynamic performances of the WCC have been found. The obtained results demonstrate that the side guards can be applied to reduce the total wind drag acting on the ship considerably.

Visual simulation of fire plays an important role in many applications, such as movies and computer games. In these applications, artists are often requested to synthesize realistic fire with a particular behavior. This paper presents two methods in order to help artists meet such requirements. First, we propose a method for controlling fire simulation by extending a previous method for smoke simulation. Controlling fire simulation with the previous method is difficult because of strong buoyancy forces caused by high-temperature. To address this problem, our method locally adjusts magnitudes of control forces. Second, we present an interactive editing method for external force field. The user can interactively design the shape of fire by placing a set of control points. Our method generates a force field to form the shape of the fire. Experimental results show that our method can control the fire into an arbitrary shape specified by the user.

To clarify the buckling/plastic collapse behaviour and strength of ship bottom plating, a series of elastoplastic large deflection FEM analyses is performed on stiffened plates subjected to combined biaxial thrust and lateral pressure. A part of continuous stiffened plate is considered for analysis taking into account of symmetry conditions. A series of elastic large deflection FEM analyses is also performed on continuous plating without stiffeners to examine the influence of lateral pressure on the buckling behaviour of plating.It has been found that : (1) When initial deflection is in a hungry horse mode, bifurcation buckling takes place. The buckling strength increases with the increase in applied lateral pressure.(2) The buckling strength is increased also by the stiffeners, which constrain the rotation of panel along its edge. An analytical formula is derived to evaluate the local buckling strength of stiffened plate considering the influence of stiffeners.(3) With the increase in applied lateral pressure, the boundary condition of the panel between stiffeners changes from simply supported condition to clamped condition. This change increases the buckling/plastic collapse strength of stiffened plate.(4) With larger lateral pressure, yielding starts earlier. This reduces the buckling/plastic collapse strength of stiffened plate.(5) Owing to the opposite effects described above, the buckling/plastic collapse strength of stiffened plate takes its maximum value at a certain magnitude of lateral pressure, especially when transverse compression is dominant.(6) The formulae by classification societies give conservative buckling strength under bi-axial compression, and the bottom plating has much reserve up to the ultimate strength even when lateral pressure is acting.

Privacy is one of the most desirable properties in modern communication systems like the Internet. There are many techniques proposed to protect message contents, but it is difficult to protect message addresses because they should be clear to message router. In this paper we propose a mechanism of one-time receiver address in IPv6 for providing unlinkability against eavesdroppers. In our system, a pair of sender and receiver independently generate an identical sequence of addresses by using a secret key exchanged in advance. The sender changes the destination address every time when it initiates a transaction, and only the corresponding receiver can follow the change of the address. We have implemented the proposed mechanism on Linux systems. The prototype system hides relation between transactions with small overhead.