Characteristics of Tsunami Damage to the Tide Walls in Iwate Prefecture from the Great East Japan Earthquake

This research paper describes the tsunami damage to tide walls observed using aerial photographs and field investigations at 13 locations along the coast of Iwate Prefecture, where significant tsunami damage occurred as a result of the Great East Japan Earthquake. This paper also summarizes the characteristics of the damage. The tide walls in Iwate Prefecture were constructed on a ria （hilly type） coast, this geographical feature of lwate being different from that of the other disaster areas, primarily Miyagi and Fukushima Prefectures. The results of our investigations show that all the devastated tide walls suffered from overflow before being damaged. In particular, the sloping and vertical type tide walls with slope protection were damaged by scouring of the infill sand or back fill soil due to the overflow of the tsunami. In the case of vertical type tide walls without slope protection, damage was caused by scouring of the back fill soil.     

The effects of psychological manners on visual and tactile evaluation of towel preferences of Turkish and Japanese consumers

This study investigated the visual and tactile evaluation of 10 towel samples made from different fiber contents. The survey was conducted by Turkish and Japanese panelists. It was also studied how psychological manners can change their preferences. To test these facts, two kinds of trial (blind test and open test) were applied on panelists. In this way, it was observed that some of the panelists changed their first preferences from synthetic fiber-based towel to natural fiber-based towel. This fact verified that psychological manners had a great effect on Turkish consumers’ preferences, and fiber content and thickness were the most distinctive properties. Then, the preferences of the panelists were ranked and the most preferred samples were determined and compared with Japanese consumers’ preferences. It was also found that Japanese people were more consistent than Turkish people and external factors and psychological manners were not effective on their decisions.     

Controlling the particle cut size of a dry cyclone using acetone

In this study, we investigated the interaction between particles and the wall in the presence of mist to improve the particle classification performance of a dry cyclone. The interaction between a silica particle and a mica surface in the presence of a flowing acetone mist was measured by performing atomic force microscopy (AFM), which showed that an attractive force was generated and became stronger as time passed while acetone mist was supplied to the system, probably because of static electricity. In a dry cyclone system, this attractive force could enhance the classification performance. In particular, when acetone mist was supplied into the cyclone from the upper part of the dust box at higher flow rates, the classification performance was enhanced. Because acetone is highly volatile and has a low viscosity, the classification performance was improved by the evaporated acetone even when a cyclone with a dust box filled with acetone was used instead of a nozzle supplying the mist. In this case, the ratio of the mass of the particles collected by the upper part of the cyclone to the total mass of the feed powder was increased, probably because of the attractive force between the silica particles and the wall of the cyclone. Moreover, the cut size of the dry cyclone could be controlled by changing the amount of acetone in the dust box of the cyclone.     

Homogenization modeling of domain switching in ferroelectric materials

We presented a multiscale nonlinear finite element simulation to analyze domain switching behaviors in ferroelectric materials. We utilized an incremental form of fundamental constitutive law to consider changes in the material properties caused by domain switching. A multiscale nonlinear problem was formulated by employing the asymptotic homogenization theory based on the perturbation method and implemented using finite element analysis. The developed simulation was applied to barium titanate with a Perovskite-type tetragonal crystal structure. The 90° and 180° domain switching behaviors of a single crystal were computed for verification. The nonlinear behaviors of a bulk polycrystal with virtual microstructure were analyzed as a case study. The variation of the crystal orientation distribution in the polycrystalline microstructure was analyzed to reveal its influence on macroscopic hysteresis and butterfly curves.     

A Geometrically Consistent Viscous Fluid Solver with Two‐Way Fluid‐Solid Coupling

We present a grid‐based fluid solver for simulating viscous materials and their interactions with solid objects. Our method formulates the implicit viscosity integration as a minimization problem with consistently estimated volume fractions to account for the sub‐grid details of free surfaces and solid boundaries. To handle the interplay between fluids and solid objects with viscosity forces, we also formulate the two‐way fluid‐solid coupling as a unified minimization problem based on the variational principle, which naturally enforces the boundary conditions. Our formulation leads to a symmetric positive definite linear system with a sparse matrix regardless of the monolithically coupled solid objects. Additionally, we present a position‐correction method using density constraints to enforce the uniform distributions of fluid particles and thus prevent the loss of fluid volumes. We demonstrate the effectiveness of our method in a wide range of viscous fluid scenarios.     

Simultaneous band reduction of two symmetric matrices

In this paper, we consider simultaneous band reduction of two dense symmetric matrices by congruent transformations. The ideas of simultaneous tridiagonalization are generalized to propose an efficient algorithm for the simultaneous band reduction. In contrast to the algorithms of simultaneous tridiagonalization which are mainly based on matrix–vector operations, the proposed algorithm of simultaneous band reduction has the advantage that matrix–matrix operations can be fully used to achieve better performance on modern computer architecture. Numerical results are presented to illustrate the effectiveness of our proposed algorithm.     

An Efficient Hybrid Incompressible SPH Solver with Interface Handling for Boundary Conditions

We propose a hybrid smoothed particle hydrodynamics solver for efficientlysimulating incompressible fluids using an interface handling method for boundary conditions in the pressure Poisson equation. We blend particle density computed with one smooth and one spiky kernel to improve the robustness against both fluid–fluid and fluid–solid collisions. To further improve the robustness and efficiency, we present a new interface handling method consisting of two components: free surface handling for Dirichlet boundary conditions and solid boundary handling for Neumann boundary conditions. Our free surface handling appropriately determines particles for Dirichlet boundary conditions using Jacobi‐based pressure prediction while our solid boundary handling introduces a new term to ensure the solvability of the linear system. We demonstrate that our method outperforms the state‐of‐the‐art particle‐based fluid solvers.