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Nagoya, Japan

The Nagoya Institute of Technology , or less commonly Nitech, is a public highest-level educational institution of science and technology located in Nagoya, Japan. Nagoya Institute of Technology was founded on 1905 as Nagoya Higher Technical School, renamed Nagoya College of Technology in 1944 then merged under the new educational system with the Aichi Prefectural College of Technology to be refounded as Nagoya Institute of Technology in 1949. Finally in 2004 it was refounded as Nagoya University Corporation Nagoya Institute of Technology. Wikipedia.

Miyazaki T.,Nagoya Institute of Technology
Progress in Materials Science | Year: 2012

A new characterization method, "Macroscopic Composition Gradient (MCG) Method" is proposed to investigate the phase transformations near the phase boundaries. The MCG method is a new technique to investigate the phase transformations in various composition alloys by utilizing a single specimen having the macroscopic solute composition gradient. Since the macroscopic composition gradient in the MCG alloy is so prepared as to cross over the phase boundary, the morphological transition of critical phenomena at the phase boundary can continuously be investigated by means of analytical transmission electron microscopy. By utilizing the MCG method, the various kinds of phase transformation, such as the coherent and incoherent precipitation boundaries, the order/disorder phase transition and the morphological change at the spinodal line have successfully been investigated. Furthermore, to an important thing, the critical size of precipitate-nucleus and the nucleation rate near the solubility limit can be experimentally obtained for respective nucleus. The phase decomposition of supersaturated solid solution progresses by a mechanism of spinodal decomposition even in the N-G region of phase diagram. On the basis of experimental results, the application limit of the conventional nucleation theory is investigated, and hence the failure of Boltzmann-Gibbs free energy becomes obvious in the early stage of phase decomposition. It is noteworthy that the present experiment is systematically conducted for the alloy composition range very close to the solubility limit. Such critical phenomena of phase transformation have been scarcely examined in the past. The MCG method proposed here is considered to open a new way to investigate the critical phenomena in the phase boundary. © 2011 Elsevier Ltd. All rights reserved.

Nakamura S.,Nagoya Institute of Technology
Organic and Biomolecular Chemistry | Year: 2014

Catalytic decarboxylative reactions are attractive as biomimetic reactions and environmentally friendly reaction processes. In this review, the origin and recent development of organocatalytic enantioselective decarboxylative reactions of malonic acid half oxy- or thioesters, or β-ketoacids are summarized. © 2014 The Royal Society of Chemistry.

Vertically oriented cylinders via the directional coalescence of the spheres embedded in the blend thin films from polystyrene-b-poly(4-hydroxyl styrene) (PS-b-PHS) and PEG induced by solvent annealing were achieved. Removal of PEG water led to the formation of nanochannels throughout the films. The diameter of these channels could be as small as 9 nm which might enhance the applicability of the nano-porous films as size-selective membranes and controllable drug delivery systems for the objects less than 10 nm.

Ruderman M.,Nagoya Institute of Technology
IEEE Transactions on Industrial Electronics | Year: 2014

In motor drives, just as in other mechanical actuators, the friction compensation is extremely important as friction can have adverse impact on the overall control performance. In this paper, a feedforward friction observer (FFFO) is proposed as formulating an explicit analytical expression for the applied observation function. This ensures the cancelation of friction disturbances and time variances at steady state. The proposed observation scheme utilizes the two-state dynamic friction model with elastoplasticity (abbreviated as 2SEP), which is compact in parameterization and captures both the presliding and sliding phases of kinetic friction. The method to identify a motor drive plant with nonlinear friction in the frequency domain has been applied using only few frequency-response-function measurements. The feedback control design is performed with respect to the time delay detectable in the system, thus under additional constraints when determining the control gains. The optimal proportional-integral (PI) control designed this way is compared with the proportional control combined with the observer (P-FFFO). The simulation results show that P-FFFO control compensates faster for frictional disturbances at suddenly changing frictional conditions than PI control. In addition, an extensive experimental evaluation of velocity tracking control discloses P-FFFO as superior in terms of a faster steady-state convergence after various transient phases. © 2013 IEEE.

Wadayama T.,Nagoya Institute of Technology
IEEE Transactions on Information Theory | Year: 2010

In the present paper, a novel decoding algorithm for low-density parity-check (LDPC) codes based on convex optimization is presented. The decoding algorithm, which is referred to hereinafter as interior point decoding, is designed for linear vector channels. The linear vector channels include several practically important channels, such as inter-symbol interference channels and partial response (PR) channels. It is shown that the maximum likelihood decoding (MLD) rule for a linear vector channel can be relaxed to a convex optimization problem, which is called a relaxed MLD problem. The proposed decoding algorithm is based on a numerical optimization technique known as the interior point method with barrier functions. Approximate variations of an interior point method based on the gradient descent and Newton methods are used to solve the relaxed MLD problem. Compared with a conventional joint message-passing decoder, from computer simulations, it is observed that the proposed decoding algorithm achieves better BER performance on PR channels with less decoding complexity in several cases. Furthermore, an extension of the proposed algorithm for high-order modulation formats, such as PAM and QAM, is presented. © 2010 IEEE.

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