Junichi Nakagawa

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We consider a one-dimensional fractional diffusion equation: ∂α t u(x, t) = ∂ ∂x ( p(x) ∂u ∂x (x, t) ) , 0 < x < `, where 0 < α < 1 and ∂α t denotes the Caputo derivative in time of order α. We attach the homogeneous Neumann boundary condition at x = 0, ` and the initial value given by the Dirac delta function. We prove that α and p(x), 0 < x < `, are(More)
To realize high scaling of a 10-Gbps-class optical access system, we propose and demonstrate two different long-reach hybrid multiplexing passive optical network (PON) systems. First, we demonstrate good scalability in the ultimate transmission distance over 100 km single-mode fiber without dispersion compensation of a 10G wavelength division multiplexing(More)
A system architecture that enhances existing videophone service with Augmented Reality (AR) technology is designed. The architecture is used to prototype an &#x201C;AiR Stamp&#x201D; system that allows users to place virtual objects on video images as if they were affixing stamps to actual scenes. System feasibility is evaluated by applying it to a remote(More)
Introduction Aromatic stacking of π-conjugated planar molecules leads to the exhibition of unique chemical and physical properties. Discotic liquid crystals are, for example, columnar assembly of aromatic compounds with long alkyl chains. Organic electroconductive materials involve alternative charge-transfer stacking of electron-donating and -accepting(More)
Today's multi-device environment, where one user has several network-capable devices, is making the idea of &#x201C;device-shift&#x201D; service a reality. In a device-shift service, a user uses multiple cooperating devices to receive a service or a set of cooperating services so that he/she can have a rich and consistent service experience. We are(More)
This paper proposes a novel bandwidth-elastic and energy-efficient passive optical network (PON) based on the coherent interleaved frequency division multiple access (IFDMA) scheme. We experimentally demonstrate the coherent IFDMA-PON uplink transmission up-to 30 Gbps over a 30 km standard single-mode fiber with 2 × optical network units (ONUs). A(More)