Nagasaki, Japan

Nagasaki Institute of Applied Science is a Japanese university located in the city of Nagasaki, Nagasaki Prefecture, Japan. Its nickname is Sōkadai and its public abbreviation is Chōsōdai. Wikipedia.


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Nakata K.,Nagasaki Institute of Applied Science | Nakata K.,Tokyo Keizai University | Zschokke S.,University of Basel
Proceedings of the Royal Society B: Biological Sciences | Year: 2010

Almost all spiders building vertical orb webs face downwards when sitting on the hubs of their webs, and their webs exhibit an up-down size asymmetry, with the lower part of the capture area being larger than the upper. However, spiders of the genus Cyclosa, which all build vertical orb webs, exhibit inter-and intraspecific variation in orientation. In particular, Cyclosa ginnaga and C. argenteoalba always face upwards, and C. octotuberculata always face downwards, whereas some C. confusa face upwards and others face downwards or even sideways. These spiders provide a unique opportunity to examine why most spiders face downwards and have asymmetrical webs. We found that upward-facing spiders had upside-down webs with larger upper parts, downward-facing spiders had normal webs with larger lower parts and sideways-facing spiders had more symmetrical webs. Downward-facing C. confusa spiders were larger than upward-and sideways-facing individuals. We also found that during prey attacks, downward-facing spiders ran significantly faster downwards than upwards, which was not the case in upwardfacing spiders. These results suggest that the spider's orientation at the hub and web asymmetry enhance its foraging efficiency by minimizing the time to reach prey trapped in the web. © 2010 The Royal Society.


Kato T.,Nagasaki Institute of Applied Science
Synthetic Metals | Year: 2011

The essential role of the phonon- and photon-coupled interactions in the electron pairing in the macroscopic sized conventional superconductivity is investigated by comparing the conventional superconductivity in the macroscopic sized materials with the nondissipative diamagnetic currents in the negatively charged small sized molecules such as cyclopentadiene monoanion (5an -) and cyclobutadiene dianion (4an 2-). The nondissipative diamagnetic currents in the negatively charged small sized molecules such as 5an - and 4an 2- cannot be explained by the Bardeen-Cooper-Schrieffer (BCS) theory because attractive phonon-coupled interactions between two electrons (V 6π,N,BCS,phonon,e-e) are zero and direct electron-electron repulsion (V 6π,N,BCS,repulsive,e-e) becomes very large. However, these phenomena in 5an - and 4an 2- can be well explained by the photon-coupled interactions between all nuclei and electrons. The phonon-coupled interactions (V phonon,e-e) play an essential role in the forming of the closed-shell electronic structures with finite valence-conduction band gaps, in which two electrons occupying the same orbitals with opposite momentum and spins become stable, and the photon-coupled interactions (V macro,photon,N,j,σ) play an essential role in attractive interactions between these two electrons. Because of the photon-coupled interactions as well as the phonon-coupled interactions, electron pairs can be formed in the macroscopic sized materials, and the conventional superconducting states can appear below the superconducting critical temperature (T c). Our molecular perspective suggested in this article is compared with the BCS theory, and the reason why the conventional superconductivity has been excellently explained by the BCS theory is also discussed. © 2011 Published by Elsevier B.V.


Kato T.,Nagasaki Institute of Applied Science
Journal of Physical Chemistry C | Year: 2011

The dependence of dimensionless electron-phonon coupling constants (λx), which play an important role in electrical conductivity and spectroscopy, on doped carriers are systematically discussed in the fractionally charged (-3.00 ≤ x ≤ -2.00) polyacene molecular crystals. The λx values for x (-2.86 ≤ x ≤ -2.71) are much larger than the λ-3.00 value. This is because the density of states at the Fermi level (NNM,intra (εF)x) values of 8 (states per molecule) for x (-2.86 ≤ x ≤ -2.71) are estimated to be much larger than the NNM,intra (εF) -3.00 value of 2 (states per molecule). In general, the λx value becomes very large if 0.50-1.00 charge of carrier with respect to the closed-shell electronic states can be doped. © 2011 American Chemical Society.


This paper deals with the modeling and control of discrete event robotic manufacturing cells using Petri nets, and proposes a methodology of model based design and implementation of hierarchical and distributed control. Hierarchical Petri net models are adopted; conceptual Petri net model and detailed Petri net model. The overall detailed Petri net model is decomposed into local Petri net models which are used by the local machine controllers. The upper level station controller coordinates the distributed local controllers so that the aggregate behavior of decomposed subnets is the same as that of the original Petri net. The overall control system is implemented using multithreaded programming based on Petri net based multitask processing. Simulation experiments show that the distributed Petri net model based control system can perform the overall multitask processing control by coincidence of the behavior of the real system with the local Petri net models. © (2011) Trans Tech Publications.


Kato T.,Nagasaki Institute of Applied Science | Kambe T.,Okayama University | Kubozono Y.,Okayama University
Physical Review Letters | Year: 2011

Superconductivity was recently discovered in solid potassium-intercalated picene (K322ph), in which the picene molecule becomes trianionic (22ph3-). In this Letter, we conduct a theory-based study of the superconductivity of 22ph3- within the framework of BCS theory. We estimate the density of states N(εF) on the Fermi level to be 2.2 states per (eVmoleculespin) by using the theoretical intramolecular electron-phonon coupling lx and the experimental superconducting transition temperature Tc of 18 K. The theoretical value is consistent with the 1.2 states per (eVmoleculespin) determined experimentally for K322ph with Tc=18K, indicating the validity of our theoretical treatment and the electron-phonon mechanism for superconductivity. The predicted lx, 0.206 eV, for 22ph3- is larger than any value reported for organic superconductors, so picene may have the largest lx among the superconductors reported so far. © 2011 American Physical Society.


Kato T.,Nagasaki Institute of Applied Science
Journal of Physical Chemistry C | Year: 2013

We investigate the vibronic stabilization energy (Δvib,-x) in aromatic 1,2:8,9-dibenzopentacene (Kx30dba) by comparison with electronic properties of aromatic hydrocarbons such as picene (K 322ph). Approximately twice larger value of the density of states at the Fermi level (N(εF)-x) for K3.1730dba than that for K330dba is the main reason why the experimental Δvib,-x value of 28.2 K for K3.1730dba is much larger than that of 7.4 K for K330dba. Approximately 5.1-5.6 and 4.3-4.8 times larger N(εF)-x values reproducing the Δvib,-3.45 values of 33.1 and 21.3 K, respectively, for K 3.4530dba than that reproducing the Δvib,-3.00 value of 7.4 K for K330dba are the main reasons why the Δvib,-3.45 values of 33.1 and 21.3 K for K3.4530dba are much larger than the Δvib,-3.00 value of 7.4 K for K 330dba. The molecular crystals of possible minimum sized molecules, with small charges, in which the stable fractionally charged (±0.50∼ ± 1.00 (in particular, ±0.57∼ ±0.86)) states with respect to the closed-shell electronic states can be realized, are the best candidates for large vibronic stabilization energies. © 2013 American Chemical Society.


Kato T.,Nagasaki Institute of Applied Science
Chemical Physics | Year: 2010

In order to discuss how the nondissipative delocalized diamagnetic currents in the microscopic sized materials are closely related to the conventional superconductivity in the macroscopic sized materials, the unified theory, by which various sized superconductivity can be explained, is suggested. It has been believed for a long time that the electron-phonon interactions play an essential role in the attractive electron-electron interactions, as described in the Bardeen-Cooper-Schrieffer (BCS) theory in the conventional superconductivity. However, it is suggested in this paper that the electron-phonon interactions do not play an essential role in the attractive electron-electron interactions but play an essential role in the forming of energy gap by which the electron pairs formed by the attractive Coulomb interactions in the conventional superconducting states become more stable than those in the normal metallic states at low temperatures. © 2010 Elsevier B.V. All rights reserved.


Yasuda G.,Nagasaki Institute of Applied Science
Proceedings of the SICE Annual Conference | Year: 2012

This paper deals with modeling and implementation problems in multiple robot control systems, especially in the field of flexible manufacturing systems. Based on conceptual condition-event models of robotic activities, extended Petri nets are adopted as a tool for expressing independent and cooperative robotic tasks by industrial intelligent robots. Net models representing inter-robot cooperation with synchronized interaction are presented, and the design of a net based real-time distributed control system which coordinates the parallel activities of the robot controllers through the transmission of commands and the reception of status, is described. © 2012 SICE.


Kato T.,Nagasaki Institute of Applied Science
Synthetic Metals | Year: 2011

The mechanism of an extraordinary increase in conductivity at larger applied voltage than the critical voltage generally observed in the one-dimensional electronic systems such as tetrathiafulvalenium- tetracyanoquinodimethanide (TTF-TCNQ) is quantitatively investigated. The tunneling effects of the nondissipative diamagnetic currents between the two neighboring localized TTF unit cells and the current-voltage characteristics at low temperature process (0 K < T < 14 K) are investigated. The transition probability (PTC) of electrons between two neighboring unit cells is estimated to be in the order of 10-3-10-4. The estimated density of states near the Fermi level in the Peierls distorted structures (NPD(εF)) on the basis of the experimental results of the current-voltage characteristics is always larger than that (N NM(εF)) in the normal metallic states in TTF-TCNQ molecular crystals. This result can be rationalized from the fact that the density of states near the Fermi level in the Peierls distorted states is enhanced as a result of the congestion of the energy levels. That is, the N PD(εF) values estimated on the basis of the tunneling effect theory suggested in this paper are well rationalized. The tunneling effects theory of the nondissipative diamagnetic currents is compared with the incommensurate charge-density-wave (ICDW) sliding theory. According to our quantitative calculated results, the phenomena described above can be understood if we consider that such an extraordinary increase in conductivity originates from the tunneling effects of the nondissipative localized diamagnetic currents between the two neighboring unit cells. © 2011 Elsevier B.V.


Shibuya K.,Nagasaki Institute of Applied Science
Physiological Measurement | Year: 2011

The brain function controlling muscle force production is not yet fully understood. The purpose of this study was to examine bilateral primary motor cortex (M1) oxygenation during static-handgrip exercises performed with the right hand (60% maximal voluntary contraction; 10 s exercise/75 s rest; five sets). Twelve healthy, right-handed male subjects participated in this study. Near-infrared spectroscopy probes were positioned over the bilateral M1 to measure cortical oxygenation during handgrip exercises. The maximum values of the changes in concentrations of oxyhemoglobin (HbO 2) and deoxyhemoglobin (Hb) across the trials (i) did not change significantly during the contralateral M1 activation (p > 0.05), whereas (ii) in the case of the ipsilateral M1 activation a significant (p < 0.05) decrease in HbO 2 and a significant (p < 0.01) decrease in Hb could be measured. The activation in ipsilateral M1 at the fifth trial was significantly decreased compared with that in the first trial (HbO 2: p < 0.001; Hb: p < 0.001). The present results suggest that the ipsilateral M1 is recruited during the motor task in compensation for the contralateral M1 and the habituation to motor task might alter the efficiency for interaction of the ipsilateral M1 to the contralateral M1. The interhemispheric interaction might change due to habituation to motor task. © 2011 Institute of Physics and Engineering in Medicine.

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