Kiyoshi Asakawa

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The authors compared levels of optimistic and pessimistic bias in the prediction of positive and negative life events between European Americans and Japanese. Study 1 showed that European Americans compared with Japanese were more likely to predict positive events to occur to self than to others. The opposite pattern emerged in the prediction of negative(More)
A technique is demonstrated which efficiently transfers light between a tapered standard single-mode optical fiber and a high-Q, ultra-small mode volume, silicon photonic crystal resonant cavity. Cavity mode quality factors of 4.7 × 10 4 are measured, and a total fiber-to-cavity coupling efficiency of 44% is demonstrated. Using this efficient cavity input(More)
A culturally relevant framework was used to examine variations on optimistic and pessimistic bias in Westerners and Easterners. Study 1 showed that 136 European Americans compared with 159 Japanese were more likely to predict typical positive events to occur to self than to a sibling. The opposite pattern emerged in the prediction of typical negative(More)
We report on the fabrication of chalcogenide glass (Ag-As 2 Se 3) photonic crystal waveguides and the first detailed characterization of the linear and nonlinear optical properties. The waveguides, fabricated by e-beam lithography and ICP etching exhibit typical transmission spectra of photonic crystal waveguides, and exhibit high optical nonlinearity.(More)
Four-wave mixing is observed in a silicon W1 photonic crystal waveguide. The dispersion dependence of the idler conversion efficiency is measured and shown to be enhanced at wavelengths exhibiting slow group velocities. A 12-dB increase in the conversion efficiency is observed. Concurrently, a decrease in the conversion bandwidth is observed due to the(More)
UNLABELLED We conducted surveys to investigate the nature of the recovery processes and psychological reactions of children and adolescents affected by the Great Hanshin Awaji Earthquake. The investigations were carried out 4 times at 4 months, 6 months, one year and two years after the disaster. SUBJECTS About 9000 school children in the 3rd grade, the(More)
BACKGROUND The psychological reactions to catastrophic events are not known well in children. PURPOSE The present study was performed to quantify the core features of post-traumatic stress reactions in schoolchildren after the Kobe earthquake. METHODS Children's psychological reactions to the Kobe earthquake were examined in a total of 8,800(More)
We perform full 3D topology optimization (in which " every voxel " of the unit cell is a degree of freedom) of photonic-crystal structures in order to find optimal omnidirectional band gaps for various symmetry groups, including fcc (including diamond), bcc, and simple-cubic lattices. Even without imposing the constraints of any fabrication process, the(More)
We describe a compact modulator based on a photonic crystal nanocavity whose resonance is electrically controlled through an integrated p-in junction. The sub-micron size of the nanocavity promises very low capacitance, high bandwidth, and efficient on-chip integration in optical interconnects. Highly efficient multi-channel drop filter in a two-dimensional(More)
Group velocity, v g , dependence of propagation loss in single-line-defect photonic crystal waveguides on GaAs membranes, and minimum loss as low as 2.5 dB=mm, are presented. When v g is reduced by a factor of 7, an additional loss is found to be only 5 dB=mm, thus proving a feasible usage of low v g. Introduction: Two-dimensional (2D) photonic crystal (PC)(More)