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Volume 44, Issue 10
Displaying 1-11 of 11 articles from this issue
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[in Japanese], [in Japanese], [in Japanese], [in Japanese]2008 Volume 44 Issue 10 Pages 767
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSDownload PDF (111K) -
Hisaya TANAKA, Ichiro MIYAMOTO, Yuji NAGASHIMA2008 Volume 44 Issue 10 Pages 768-775
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSPhysiological examination of language comprehension mechanism of the sign language is necessary in order to study language recognition, video communication, animation generation of JSL (Japanese Sign Language), or sign language education. In this paper, the semantic deviation sentences and the meaningless operations were sampled. These sentences were played by a native JSL speaker, and was recorded and edited. Then, the trigger frame of the stimulation start was analyzed, and N400event related potential was measured. As the result, N400in semantic deviation word of JSL was increased in comparison with the meaningless operation, though the individual difference existed. Next, semantic analysis process during the signing and on the reading were examined. As the result, N400increased in both of the signing and the reading in the semantic incongruity, and the button reaction time in the signing increased in comparison with the reading. Thus, the effect of the modality of the language was considered. In addition, on a hearing and a deaf, cerebrum activity of the processing of letter was estimated by Focus, and the difference between the semantic process was observed. The analysis procedure of semantic analysis mechanism of the deaf was examined, and some qualitative fact was confirmed.View full abstractDownload PDF (13571K) -
Seiji NISHIFUJI, Iyo MIYAHARA2008 Volume 44 Issue 10 Pages 776-778
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSBrain alpha wave responses to unpleasant and pleasant sounds are investigated in terms of the amplitude and phase. The amplitude of the alpha wave is significantly reduced during listening to the unpleasant sounds, e. g., teeth gnashing and a single frequency tone with a frequency of 5 KHz as well as listening to the pleasant sounds, e. g., Pachelbel's Canon and babble of a stream. Such amplitude instability is found to be prolonged at least for 100 s after listening to the sounds. Moreover, temporal phase change rate of the alpha wave is increased during and after listening to the unpleasant sounds, whereas it is not significantly increased for the pleasant sound. The effects of the unpleasant sounds on the alpha wave seem to remain in the brain electrical activity for a longer period.View full abstractDownload PDF (4330K) -
Nobuyuki TANAKA, Mitsuru HIGASHIMORI, Makoto KANEKO2008 Volume 44 Issue 10 Pages 779-785
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper discusses active sensing for detecting viscoelastic parameters of living tissues with the coupling effect among neighbours. Supposing that both applied force and surface deformation of tissue are known with respect to time, we obtain viscoelestac parameters of living tissue by utilizing a single layered model with horizontaland vertical units where each unit is composed of both stiffness and damping elements. We show that the model with only appropriate number of units can nicely express the dynamic characteristic of human skin.View full abstractDownload PDF (12516K) -
Yuichi TAZAKI, Jun-ichi IMURA2008 Volume 44 Issue 10 Pages 786-792
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSOptimal control and reachability analysis of continuous-state systems often require computational algorithms with high complexity. The use of discrete-state abstractions of continous-state systems reduces such problems to path-planning problems on directed graphs with a finite number of nodes, which can be computed efficiently. In this paper, we propose a method to design discrete abstractions of stabilizable discrete-time linear systems based on the notion of approximate bisimulation. Moreover, we show that a suboptimal solution to optimal control problems with a known bound on performance deterioration is obtained by making use of discrete abstraction.View full abstractDownload PDF (8906K) -
Hiroshi OKAJIMA, Toru ASAI, Shigeyasu KAWAJI2008 Volume 44 Issue 10 Pages 793-801
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper is concerned with optimal reference tracking control problem for discrete time 1-DOF/2-DOF systems. It is well known that l2 norm of an error, which is defined by difference between an output and a reference, does not turn zero for all possible controllers when plant is given as a non-minimum phase system. Purpose of this research is to derive closed-form expression of the optimal value of l2 norm of the error and its controller. The references for tracking are e.g. step, sine, impulse train, triangle wave and linear combination of these signals. Therefore, we can handle various signals as a reference. Moreover, our results can also characterize impact of the relative degree of plant. Those effectiveness are shown by numerical examples.View full abstractDownload PDF (5061K) -
Hisanosuke KAWADA, Kouei YOSHIDA, Toru NAMERIKAWA2008 Volume 44 Issue 10 Pages 802-808
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper addresses the problem of the control of bilateral teleoperation with different configurations and communication delays. We propose a synchronized control law with individual gains and power scaling in the task space. Using this method, the end-effector motion and force relationship between the master and slave robots can be specified freely in the task space and the control gains can be independently selected appropriately for the master and slave robots. The passivity of the whole system is proven by using an energy function. Furthermore, the delay-independent asymptotic stability of the origin of the position and velocity errors is proven by using Lyapunov like stability methods in free space and the proposed control law achieves scaled synchronization of the teleoperation. Several experimental results show the effectiveness of our proposed method.View full abstractDownload PDF (5965K) -
Hideyuki YAGI, Jiro SHIMONISHI, Toru YAMAMOTO, Takao HINAMOTO2008 Volume 44 Issue 10 Pages 809-818
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSPID controllers have been very widely used for various process control systems represented by chemical processes. Recently, from viewpoint of the productivity improvement and the cost decrease, it is requested to establish the method obtained a good performance PID controller over time on steady-state in spite of changes in a system characteristic. In this research, a design of performance-driven predictive PID controllers is proposed, which automatically adjusts the user- specified parameter within the GPC- PID controller based on the control performance assessment. From a point of the control performance on steady- state, it is investigated that the GPC- PID controller is superior to typical controllers. The practically performance index to assess good controller or not is described and the design benchmark of weighting factor included in the cost function which is one of the user- specified parameter is presented. Finally, numerical simulation is provided to verify the validity of the proposed method.View full abstractDownload PDF (10936K) -
Hiroaki YAMAGUCHI, Masato MORI, Atsushi KAWAKAMI2008 Volume 44 Issue 10 Pages 819-828
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSThis paper presents a design methodology of a path following feedback control system using parametric curves for a cooperative transportation system with two car-like mobile robots. Specifically, the authors first present a numerical method for transforming the position and the orientation of the cooperative transportation system in the Cartesian coordinate system into those in a new coordinate system in which a parametric curve path is an axis and a straight line perpendicular to the tangent of the path is another axis. Especially, the kinematical equation of the cooperative transportation system is convertible to chained form in the new coordinate system. The authors secondly present a numerical method for calculating the second differential of the curvature of the parametric curve path which is much faster than an analytical method. These two numerical methods are embedded in the path following feedback control system, and it is possible to execute the two numerical methods in an effective control period for the path following feedback control system. The authors design a path following feedback control system using a parametric curve path, e.g., a twelve-order bezier path, for driving an experimental system developed, e.g., a cooperative transportation system with two tricycle mobile robots kinematically equivalent to the car-like mobile robots, into a garage in which clearance is tight. Such driving motion is reproduced with high reliability. Therefore, the validity of the designed path following feedback control system is verified experimentally.View full abstractDownload PDF (17462K) -
Akira KOJIMA, Yousuke ICHIKAWA2008 Volume 44 Issue 10 Pages 829-837
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSFor multiple input delay systems, a robust stabilization problem in the gap-metric is solved and an observerbased predictive control law is clarified. Based on the control law obtained here, the H∞ loop-shaping procedure is applied to some numerical examples and the effect of input time delay is discussed. It is also illustrated that the advantage of minimum phase structure in the delay-free plant is vulnerable to the transmission delay.View full abstractDownload PDF (2194K) -
Shigeharu KAWAI, Makio ISHIGURO, Yoshitaka OKU2008 Volume 44 Issue 10 Pages 838-845
Published: October 31, 2008
Released on J-STAGE: February 25, 2013
JOURNAL FREE ACCESSHodgkin and Huxley (1952) contrived a single neuron model (Hodgkin-Huxley model, or HH model) which was given in the form of non linear differential equations of four variables. This model simulates the variation of the cell membrane potential by an electric circuit composed of condensers, resisters and embedded gates through which the sodium and potassium ion current pass. HH model was treated mainly as a deterministic model for simulations and analysis in the past.
We treat HH model as a non-linear stochastic process which will mimic the behavior of the neuron of as a part of the active neural circuit. Discretization is a natural way to treat stochastic process by digital computer. As a general method of discretization of nonlinear stochastic process, Ozaki (1993) proposed ‘the local linearization method’ and applied it to the Van del Pol equation etc., and verified its goodness in precision. Though HH model is more complicated multi variate system, we prove that the combination of the local linearization method and Kalman filter can be effectively applied to HH model. Next, we augment the state equation by introducing the exogenous current trend input. The trend input can be estimated via smoothing procedure. Even if the model parameters are unknown, both the exogenous current input and the model parameters can be estimated simultaneously by the maximum likelihood method.View full abstractDownload PDF (4927K)
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