Yokohama National University , or Yokokoku is a leading national university located in Yokohama, Kanagawa Prefecture, Japan. Yokohama National University comprises 5 graduate schools and 4 undergraduate faculties. Yokohama National University is one of leading national universities in Japan. It is consistently one of the highest ranking national universities in Japan that is not one of Japan's National Seven Universities. It is also a core member of the Port-City University League. Wikipedia.
Yoshitake H.,Yokohama National University
Journal of Materials Chemistry | Year: 2010
In this review the preparation and adsorption phenomena specific to functionalized mesoporous silicas are discussed for designing the optimum structures of adsorbents for the removal of aqueous pollutants. The topics mainly described are control of spacing of functional groups on the surface, selective functionalization of characteristic sites in the mesostructure and the effects of mesopore confinement. Comparisons with synthetic pendant polymers and other organo-siliceous oxides in a periodic structure are performed in order to illustrate the adsorption features of functionalized silicas clearly. © 2010 The Royal Society of Chemistry.
Konno N.,Yokohama National University
Quantum Information Processing | Year: 2010
We investigate a space-inhomogeneous discrete-time quantumwalk in one dimension. We show that the walk exhibits localization by a path counting method.
Sumi Y.,Yokohama National University
International Journal of Fatigue | Year: 2014
In order to prevent the initiation of a brittle crack in a marine structure, fatigue crack propagation from potentially hazardous embedded weld defects must be evaluated under the realistic seaway loading using certain clustered loading patterns. We first simulate the fatigue crack propagation under the random sequence of clustered loading so-called storm model. The numerical simulation is carried out by a method considering the plastic wake on the crack surfaces, which may cause the retardation effects after high amplitude of loading. Furthermore, fatigue crack propagation under the effect of slam-induced whipping stress is examined by a series of experiments using CT specimens and by simulations. © 2013 Elsevier Ltd. All rights reserved.
Ochiai H.,Yokohama National University
IEEE Transactions on Wireless Communications | Year: 2011
We develop two approaches to calculating statistical distributions of instantaneous power of pulse-shaped single-carrier signals. Our first approach is to derive a formula that can calculate exact distributions of pulse-shaped signals with arbitrary constellations. The exact approach is versatile but turns out to be computationally demanding except for some cases where the constellation has circular symmetry. Our second approach is thus based on approximation, which is valid only for M-ary phase shift keying (MPSK) or phase-shifted MPSK constellations, but requires substantially less computation. The validity of the proposed approaches is confirmed by numerical analysis. © 2011 IEEE.
Guo P.,Yokohama National University
IEEE Transactions on Systems, Man, and Cybernetics Part A:Systems and Humans | Year: 2011
This paper focuses on one-shot (one-time) decision problems, which concern the situations where a decision is experienced only once. Such one-shot decision problems are commonly encountered in business, economics, and social systems. The one-shot decision process comprises two steps. In the first step, a decision maker identifies which state of nature should be taken into account for each alternative among all available states of nature. These identified states of nature are called focus points. Twelve types of focus points are proposed according to a decision maker's attitudes about the possibility of a state of nature and satisfaction resulted by its occurrence. In the second step, a decision maker evaluates the alternatives based on focus points where the consequences provided by all alternatives are compared with each other to obtain the best alternative. The relationships between different focus points are analyzed. An example, which is a newsvendor problem of a new product with a short life cycle, is used to illustrate the one-shot decision. The results of analysis show that the proposed decision models can provide useful insights into understanding different behaviors of decision makers and help the decision maker in finding out the best solution according to his/her attitude about possibility and satisfaction. © 2011 IEEE.