start-ver=1.4 cd-journal=joma no-vol=12 cd-vols= no-issue=1 article-no= start-page=14172 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2022 dt-pub=20220819 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Visual hallucinations in dementia with Lewy bodies originate from necrosis of characteristic neurons and connections in three-module perception model en-subtitle= kn-subtitle= en-abstract= kn-abstract=Mathematical and computational approaches were used to investigate dementia with Lewy bodies (DLB), in which recurrent complex visual hallucinations (RCVH) is a very characteristic symptom. Beginning with interpretative analyses of pathological symptoms of patients with RCVH-DLB in comparison with the veridical perceptions of normal subjects, we constructed a three-module scenario concerning function giving rise to perception. The three modules were the visual input module, the memory module, and the perceiving module. Each module interacts with the others, and veridical perceptions were regarded as a certain convergence to one of the perceiving attractors sustained by self-consistent collective fields among the modules. Once a rather large but inhomogeneously distributed area of necrotic neurons and dysfunctional synaptic connections developed due to network disease, causing irreversible damage, then bottom-up information from the input module to both the memory and perceiving modules were severely impaired. These changes made the collective fields unstable and caused transient emergence of mismatched perceiving attractors. This may account for the reason why DLB patients see things that are not there. With the use of our computational model and experiments, the scenario was recreated with complex bifurcation phenomena associated with the destabilization of collective field dynamics in very high-dimensional state space. en-copyright= kn-copyright= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=FujiiHiroshi en-aut-sei=Fujii en-aut-mei=Hiroshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TsukadaHiromichi en-aut-sei=Tsukada en-aut-mei=Hiromichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=TsudaIchiro en-aut-sei=Tsuda en-aut-mei=Ichiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= affil-num=2 en-affil=Faculty of Information Science and Engineering, Kyoto Sangyo University kn-affil= affil-num=3 en-affil=Center for Mathematical Science and Artifcial Intelligence/Chubu University Academy of Emerging Sciences, Chubu University kn-affil= affil-num=4 en-affil=Chubu University Academy of Emerging Sciences/Center for Mathematical Science and Artifcial Intelligence, Chubu University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=29 cd-vols= no-issue=1 article-no= start-page=7 end-page=14 dt-received= dt-revised= dt-accepted= dt-pub-year=1994 dt-pub=19941130 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Electronic States in Semiconductor Quantum Dot with Fluctuating Interfaces en-subtitle= kn-subtitle= en-abstract= kn-abstract=Effects of interface fluctuations on the electronic states in semiconductor quantum dots are analyzed on the basis of numerical solutions for ground state wave functions and energy eigenvalues. It is shown that the effective volume of confinement becomes smaller than the real volume of quantum dots due to fluctuation. This effect comes from the fact that the wave functions with larger characteristic wavelength are not able to deform themselves following the fluctuation of interfaces exactly. en-copyright= kn-copyright= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=HiroyukiTachibana kn-aut-sei=Hiroyuki kn-aut-mei=Tachibana aut-affil-num=1 ORCID= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=2 ORCID= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=3 ORCID= en-aut-name=TotsujiChieko en-aut-sei=Totsuji en-aut-mei=Chieko kn-aut-name=東辻千枝子 kn-aut-sei=東辻 kn-aut-mei=千枝子 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=4 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=28 cd-vols= no-issue=2 article-no= start-page=45 end-page=52 dt-received= dt-revised= dt-accepted= dt-pub-year=1994 dt-pub=19940315 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Numerical Simulation of Quantum Systems -Dynamics of Electrons in Microstructures- en-subtitle= kn-subtitle= en-abstract= kn-abstract=Difficulties in simulating systems composed of classical and quantum particles lie in the treatment of the many-body interactions between quantum particles and the geometrical variety of configurations of classical particles. In order to overcome these difficulties, we have developed some numerical methods and applied them to simple cases. As for stationary states, the finite element method provides us with sufficient geometrical freedom. Combined with the Kohn-Sham equation based on the density functional theory, this method virtually satisfies our requirement. In order to investigate time-dependent phenomena, we apply the time-dependent Kohn-Sham equation. Adopting the finite difference method, we are able to follow the development of quantum many-body system. As an example, we estimate the effects of the potential height, the electric field, and many-body interactions in some transition processes in quantum wells coupled by a tunneling barrier. This example is important in itself in relation to semiconductor superlattices and also serves as a benchmark for quantum simulations, variety of geometry corresponding to that of classical particles. en-copyright= kn-copyright= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=1 ORCID= en-aut-name=HashimotoSeiji en-aut-sei=Hashimoto en-aut-mei=Seiji kn-aut-name=橋本成仁 kn-aut-sei=橋本 kn-aut-mei=成仁 aut-affil-num=2 ORCID= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=26 cd-vols= no-issue=2 article-no= start-page=111 end-page=128 dt-received= dt-revised= dt-accepted= dt-pub-year=1992 dt-pub=19920328 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Memory Search using Genetic Algorithms and a Neural Network Model en-subtitle= kn-subtitle= en-abstract= kn-abstract=An information processing task which generates combinatorial explosion and program complexity when it is treated by a serial algorithm is investigated using both Genetic Algorithms (GA) and a neural network model (NN). The task in question is to find a target memory from a set of stored entries in the form of "attractors" in a high dimensional state space. The representation of entries in the memory is distributed ("an auto associative neural network" in this paper), and the problem is to find an attractor under a given access information where the uniqueness or even existence of a solution is not always guaranteed ( an ill-posed problem ). The GA is used as an algorithm for generating a search orbit to search effectively for a state which satisfies the access condition and belongs to the target attractor basin in state space. The NN is used to retrieve the corresponding entry from the network. The results of our computer simulation indicate that the present method is superior to a search method which uses random walk in state space. Our technique may prove useful in the realization of flexible and adaptive information processing, since pattern search in high dimensional state spaces is common in various kinds of parallel information processing. en-copyright= kn-copyright= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=BanzhafWolfgag kn-aut-sei=Banzhaf kn-aut-mei=Wolfgag aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Central Research Laboratory, Mitsubishi Electric Corporation END start-ver=1.4 cd-journal=joma no-vol=28 cd-vols= no-issue=1 article-no= start-page=27 end-page=38 dt-received= dt-revised= dt-accepted= dt-pub-year=1993 dt-pub=19931130 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Ground State of Coupled Quantum Wires en-subtitle= kn-subtitle= en-abstract= kn-abstract=The ground states of interacting electrons in coupled quantum wires are analyzed on the basis of the density functional theory. The exchange-correlation potential is calculated from 'exact' results given by the Green's function Monte Carlo method in two and three dimensions. It is shown that the critical density signifying the change from symmetrical to asymmetrical ground state is weakly dependent on the details of the exchange-correlation potential. These critical values are compared with the result of the three-dimensional analysis for a single wire. en-copyright= kn-copyright= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=TachibanaHiroyuki kn-aut-sei=Tachibana kn-aut-mei=Hiroyuki aut-affil-num=2 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=FujimuraHidenori kn-aut-sei=Fujimura kn-aut-mei=Hidenori aut-affil-num=3 ORCID= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=4 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=28 cd-vols= no-issue=1 article-no= start-page=1 end-page=25 dt-received= dt-revised= dt-accepted= dt-pub-year=1993 dt-pub=19931130 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=A Simple Method to Evaluate Structural Stability of Group IV and III-V Semiconductors en-subtitle= kn-subtitle= en-abstract= kn-abstract=The structural stabilities of bulk Si, Ge, and GaAs are discussed based on the total energy evaluated by the summation of the band structure energy and the short-range repulsive potential between ions. The band structure energy is calculated by means of the simple tight-binding method. The tight-binding parameters are determined so as to fit to the results of a pseude potential calculation and Harrison's model is employed to include the influence of lattice deformation. The short-range-force is assumed to be of the exponential form and parameters are determined so as to reproduce an experimental value of bulk modulus. This treatment qualitatively well describes structural properties in spite of the simple computational procedure and roughly gives the known variation of the total energy for a <100> uniaxial strain. This method is able to be applied to an investigation of the structural stabilities of superlattices, for example, a strained layer superlattice consisting of hetero-semiconductors. en-copyright= kn-copyright= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=MihoShigeru kn-aut-sei=Miho kn-aut-mei=Shigeru aut-affil-num=2 ORCID= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=26 cd-vols= no-issue=1 article-no= start-page=51 end-page=59 dt-received= dt-revised= dt-accepted= dt-pub-year=1991 dt-pub=19911130 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Molecular Dynamics ofa Coulomb System with Deformable Periodic Boundary Conditions en-subtitle= kn-subtitle= en-abstract= kn-abstract=Variable shape molecular dynamics is formulated for the one-component plasma and the structural transition from the fcc lattice to the bcc lattice has been observed. It is emphasized that the condition of constant volume should be imposed when deformations of periodic boundary conditions are taken into account. en-copyright= kn-copyright= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=ShirokoshiHideki kn-aut-sei=Shirokoshi kn-aut-mei=Hideki aut-affil-num=2 ORCID= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=27 cd-vols= no-issue=2 article-no= start-page=19 end-page=40 dt-received= dt-revised= dt-accepted= dt-pub-year=1993 dt-pub=19930325 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Complex Dynamics and Search in A Cycle-Memory Neural Network en-subtitle= kn-subtitle= en-abstract= kn-abstract=Numerical simulations of a single layer recurrent neural network model in which the synaptic connection matrix is formed by summing cyclic products of succesive patterns show that complex dynamics can occur with the reduction of a connectivity parameter which is the number of connection between neurons. The structure in these dynamics is discussed from the viewpoint of realizing complex function using complex dynamics. en-copyright= kn-copyright= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=1 ORCID= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=Department of ElectricaJ and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of ElectricaJ and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=27 cd-vols= no-issue=1 article-no= start-page=65 end-page=79 dt-received= dt-revised= dt-accepted= dt-pub-year=1992 dt-pub=19921125 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Electronic States and Electron Wave Transfer in Coupled Quantum Wires and Its Control by Externally Applied Electric Field en-subtitle= kn-subtitle= en-abstract= kn-abstract=Quantum mechnical electron wave transfer between two quantum wires which are weakly coupled via a thin potential barrier is considered. The total electronic states are calculated with both analytical ( no field case ) and numerical methods ( under applied electric fields ). The transfer efficiency is evaluated for several specified cases of geometrical structures, potential barrier heights and the externally applied electric field. Estimated trasfer time is of the order of one picosecond in typical mesoscopic structures. The model in this paper can be used to determine important structure parameters for experiments on electron directional coupler controled by external elctric field. en-copyright= kn-copyright= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=HaraYuji kn-aut-sei=Hara kn-aut-mei=Yuji aut-affil-num=2 ORCID= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Sharp Corporation affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=27 cd-vols= no-issue=1 article-no= start-page=55 end-page=64 dt-received= dt-revised= dt-accepted= dt-pub-year=1992 dt-pub=19921125 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Intrinsic Bistability of Coupled Quantum Wires: Localization due to Many-Body Effects en-subtitle= kn-subtitle= en-abstract= kn-abstract=The ground state of a system of electrons accumulated in a pair of coupled symmetric quantum wires is analyzed on the basis of density functional theory. It is shown that, in a domain of physical parameters, electrons are localized in either of wires. The main contribution to the total energy of this system comes from the Hartree energy, or the electrostatic energy, and the exchange-correlation energy between electrons. The ground state is determined by a competition between these contributions: We have symmetric electron distributions when the Hartree energy dominates and asymmetric (localized) states are realized in the opposite case. This kind of simple system with bistable electronic states may be applied to semiconductor memory devices. en-copyright= kn-copyright= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=TachibanaHiroyuki kn-aut-sei=Tachibana kn-aut-mei=Hiroyuki aut-affil-num=2 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=HashimotoSeiji kn-aut-sei=Hashimoto kn-aut-mei=Seiji aut-affil-num=3 ORCID= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=4 en-affil= kn-affil=Department of Electrical and Electronic Engineering END start-ver=1.4 cd-journal=joma no-vol=30 cd-vols= no-issue=1 article-no= start-page=75 end-page=87 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=19951228 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Molecular Dynamics of Yukawa System (Dust Plasma) with Deformable Periodic Boundary Conditions: Formulation en-subtitle= kn-subtitle= en-abstract= kn-abstract=Molecular dynamics of the Yukawa system, the system of particles interacting via the Yukawa or the screened Coulomb potential, are formulated for various statistical ensembles and external conditions. The Yukawa potential smoothly interpolates the long-range Coulomb and the short-range interactions by adjusting a single parameter, the screening length. In order to reduce the effect of boundaries, the periodic boundary conditions are imposed and the deformations of the fundamental vectors of periodicity are taken into account. Ewald-type expressions for interaction energy, force, and kinematic pressure are given explicitly. en-copyright= kn-copyright= en-aut-name=TotsujiHiroo en-aut-sei=Totsuji en-aut-mei=Hiroo kn-aut-name=東辻浩夫 kn-aut-sei=東辻 kn-aut-mei=浩夫 aut-affil-num=1 ORCID= en-aut-name=InoueYoshihiko en-aut-sei=Inoue en-aut-mei=Yoshihiko kn-aut-name=井上嘉彦 kn-aut-sei=井上 kn-aut-mei=嘉彦 aut-affil-num=2 ORCID= en-aut-name=KishimotoTokunari en-aut-sei=Kishimoto en-aut-mei=Tokunari kn-aut-name=岸本篤也 kn-aut-sei=岸本 kn-aut-mei=篤也 aut-affil-num=3 ORCID= en-aut-name=TotsujiChieko en-aut-sei=Totsuji en-aut-mei=Chieko kn-aut-name=東辻千枝子 kn-aut-sei=東辻 kn-aut-mei=千枝子 aut-affil-num=4 ORCID= en-aut-name=NaraShigetoshi en-aut-sei=Nara en-aut-mei=Shigetoshi kn-aut-name=奈良重俊 kn-aut-sei=奈良 kn-aut-mei=重俊 aut-affil-num=5 ORCID= affil-num=1 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=2 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=3 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=4 en-affil= kn-affil=Department of Electrical and Electronic Engineering affil-num=5 en-affil= kn-affil=Faculty ofIntegrated Arts and Sciences, Hiroshima University END