Anatase Nb-doped TiO_2 transparent conducting oxide has been formed on GaN(0001) surfaces using asputtering method.Amorphous films deposited at room temperature were annealed at a substrate temperature of 500℃ in vacuum to form single-phase anatase films.Films with a thickness of 170 nm exhibited a resistivity of 8×10^-4Ωcm with absorptance less than 5% at a wavelength of 460 nm.Furthermore,the refractive index of the Nb-doped TiO_2 was well matched to that of GaN. These findings indicate that Nb-doped TiO_2 is a promising material for use as transparent electrodes in GaN-based light emitting diodes(LEDs),particularly since reflection at the electrode/GaN boundary can be suppressed,enhancing the external quantum efficiency of blue LEDs.

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Although plasma-assisted molecular beam epitaxy(PA-MBE) is a promising technique for GaN growth,the growth rate obtained by this technique is lower than that obtained by metal organic vapor phase epitaxy(MOVPE).In order to improve the growth rate of the technique,high density radical source(HDRS) was developed.By vacuum ultraviolet absorption spectroscopy(VUVAS) measurement,two orders of magnitude higher radical density was confirmed in a comparison of the HDRS and a conventional radical source(CRS).While faster growth rate of 1.4μm/h in GaN homoepitaxy was achieved,better crystalline quality of InxGa_<(1-x)>N(x=0.03〜0.16) epilayers with approximately 1.4μm thickness were also achieved by introducing the HDRS in PA-MBE.

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The etch characteristics such as etch rates of sapphire and resist, etch selectivity over resist, and sidewalldeposition was studied in an inductively coupled plasma etcher using BCl_3/ CHF_3 plasmas in order to fabricate nano-patterned sapphire substrates(NPSS).In the etch conditions with bias power 100W and Antenna power 800W,the anisotropic sapphire etch profile could be observed by scanning electron microscope.The increase of chf_3 1n CHF_3/BC1_3 increased the thickness of the sidewall deposition.The etch mask used UV-curenanoimprint resist and an etch selectivity greater than 10 could be obtained at a lower working pressure (0.3Pa)in BCl_3/CHF_3 plasmas.

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We developed a pattern shape control technique of wet etching Patterned Sapphire Substrate(PSS) by applying Chemical Mechanical Polishing (CMP).We evaluated Round Rate(RR) as a degree of pattern roundness.RR increased with increasing the concentration of colloidal silica,but above 1% concentration of colloidal silica,RR abruptly decreased.The higher applied pressure caused not only higher RR but also reduction of pattern height,which indicates that lower pressure is appropriate for pattern shape control

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Dry etching process used for the fabrication of power devices requires high level process technology and highly advanced systems.What is especially difficult in the dry etching process for power device fabrication is GaN/AlGaN recess etching for gate formation.2DEG must be eliminated to realize normally-off type powerdevices,and one of the solutions is to make AlGaN layer very thin. In order to etch away 20nm from AlGaN layer that is initially 25nm thick, and to realize stable device properties such as Vg-Id, it is extremely important to precisely control the thickness of 25nm.Our challenges of recess etching include(i) low etch rate process,(ii) end point detection,(iii) bottom smoothness,and (iv) device damage.We developed a new etching process to solve these challenges and new technology to optically monitor remaining layer thickness during dryetching

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The transparent electrodes on GaN were formed by the screen printing of indium tin oxide nanoparticle(ITOnp) pastes as wet process in place of sputter deposition of metal oxides as dry process. The ITO nps were synthesized by the controllled thermolysis of the mixture of indium complexes and tin complexes.The ITO nppastes were prepared by three-roll milling of the mixture of the solvent, the resin,and the ITO nps.The direct printing of ITO np pastes were carried out by screen printing on GaN substrates.After printing,the transparent conductive ITO film was formed by sintering at 850°C for 10 minutes under the atmospheric condition. The produced device emitted light when the on-voltage was exceeded.

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It is very difficult to produce a smooth and damage-free gallium nitride(GaN) surface using the conventional polishing method utilized for silicon wafer processing because of the hardness,brittleness and chemicalinertness of GaN.We have developed a novel polishing method named CARE(catalyst-referred etching),which is an abrasive-free chemical polishing method involving a chemical reaction between the surface of a workpiece and a catalytic plate in a chemical solution or pure water.Here,we report that a GaN substrate with a damage-free and atomically smooth surface can be obtained by the CARE process

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The near-future process of semiconductor wafer planarization for hard-to-process wide bandgap semiconductor,such as gallium nitride (GaN),silicon carbide (SiC), and semiconductor diamond which isthought to be the ultimate semiconductor material is proposed.The process is divided into two steps.First,the bulk material is processed by femtosecond laser,results in the pseudo-radical state over the surface.Next,theprocessed specimen is introduced to the novel CMP machine,which is merged together with plasma CVM apparatus.This study we introduce the polishing process and concepts in the new planarization process, and report some results of the preliminary experiments.

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A heat sink with high thermal conductivity is very important part to achieve high efficient and stablenitride semi conductors,such as an optical device for short wavelength laser.Diamond is one of the candidate materials for extremely high thermal conductive heat sink.However,it is difficult to make the diamondsubstrate surface flat in order to obtain a good contact with the laser chip.This paper focuses on a polish ingcharacteristics in terms of crystal orientation on(100) face.As a result,the highest polishing rate is achieved when the polishing direction is in parallel to the <100> crystal orientation.0n the other hand,the lowestpolishing rate but the smoothest surface is obtained in case of the<110>crystal orientation.

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Recently,micro/nano-systems have been required to satisfy the integration,further miniaturization,and shortening fabrication process time for more complex application.In the case of micro Total Analysis Systems,many types of microfluidic components,i.e.microchannels,microvalves,micromixers,and micropumps are integrated on a chip.In this study,we propose a simple-structural micropump having a magnetically-driven diaphragm made of a photosensitive nanocomposite for an easy integration method.A fabricated micropump generated the one-directional fluid flow at the flow rate of 0.35μ1/min evaluated by using image analysis with fluorescent microscope images.

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In micro Total Analysis Systems(μ-TAS) field,polydimethylsiloxane(PDMS) is widely used for the structural material of a microfluidic device. However,a large scale integration of the microfluidic system becomes a laborious process because of theshrinkage of PDMS at curing process.In this study,we quantitatively evaluated the shrinkage of PDMS depend on the curing temperature,the curing time and the thickness of PDMS samples.As a result,it is seen that there is correlation between total heattransfer per unit volume and the shrinkage of PDMS.Especially,the initial heat treatment has significant effect for the saturated value of the shrinkage.

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In this study,we aim to establish traceability at calibration and thus enable certified flow measurement within a calibrated measurement system.Here,a new calibration method is presented for laser velocimetry.We developed a simple,unique method to establish traceability of its uncertainty.Our new method only requires a rotating disk and a precision linear stage to provide positional information. With past calibration methods.the uncertainty of the orbit radius of a scattering object was dominant because of the difficulty in accessing the true center of the rotation.This difficulty is solved with our new methodas it provides a reliable estimate of the or bit radius and hence the velocity of the calibration object through a linear regression.The uncertainty budget is examined throughout the calibration procedure.The traceability chain is established once the traceabilities are obtained to the translation stage and the motor used for rotating the calibration disk.We tested this new method with three different calibration setups and investigated their performances.The tests show that uncertainty could be determined as low as 0.14%,which is lower than the limit of an ordinary laser velocimetry around 0.3 %.

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In this study,we developed microfabrication process of lead-free sodium potassium niobate [(K,Na)NbO_3,KNN]thin films by dry etching.We deposited KNN thin films on Si substrate and evaluated its etching characteristics.We found that Ar/C_4F_8 plasma dry etching was effective for high etching rate 63 nm/min of KNN as well as excellent selectivity of KNN and Cr metal mask 5.7.We conducted fabrication of Pt/KNN/Pt unimorph microcantilevers through KNN etching process.We could fabricate micro-cantilevers without initial deflection and they show high piezoelectric coefficients d_31=110 pm/V.These results suggest that Ar/C_4F_8 plasma dry etching enable to apply for various lead-free piezoelectric MEMS fabrication processes.

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We developed piezoelectric MEMS gyrosensors composed of PZT thin films. The PZT thin films were directly deposited on the microfabricated metal cantilevers by RF sputtering method.To evaluate basic performance of the gyrosensor,we measured resonance frequency of horizontal and vertical directions.We clearly observed horizontal and vertical resonances at 48.46kHz and 28.77 kHz respectively.Then we calculated the sensitivity analytically.

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We fabricated piezoelectric energy harvesters composed of c-axis oriented Pb(Zr,Ti)O_3 (PZT) thin films transferred onto stainless steel substrates.In order to improve resonance frequency,we designed a cantilever with a tip mass.PZT thin firms were epitaxially grown on MgO substrates using rf-magnetoron sputtering and transferred onto stainless steel substrate by eximer laser liftoff.Transferred PZT thin firms had a low dielectric constant (ε_r=340) and high piezoelectric coefficient(e_<31.1>=-4.76 C/m^2).The energy harvester had a resonance frequency of 143.2 Hz.At the optimal load resistance of 90 kΩ and resonance frequency of 143.2 Hz, theenergy harvester generated output power of 2.02μW at an acceleration of 1m/s^2 and 49μW at acceleration of 7.5 m/s^2.

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We have been developing an electret comb-drive actuator that employs silicon oxide film as an electret material.Here in this time,we will report on electrical characterization of the electret pendulum actuator as a power generator.We measured generated voltage by impulse response,and we obtained 20 mV_<pp> generated voltage when it vibrate 850 Hz.In addition,its Q factor is about 20000,this factor is much higher than conventional product.

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In recent years,many researches of a large deflection MEMS mirror having polymer hinges have been actively done.Since the polymer materials have the demerits of time and temperature dependencies of the mechanical property related to the reproducibility of the mirror position,sensing and controlling of the mirror angle are necessary for realize a stable laser scan.In this paper,we propose a polymer-MEMS mirror integrated an angular rate sensor.The mirror is electromagnetically driven by the Lorentz force,and the mirror angle is measured by the induced electromotive force of the sensor coil on the mirror.A prototype of the fabricated mirror deflected over±30 degree and generated the sensor signal at the sensor coil.So,it is possible that the proposed mirror integrated the angular rate sensor on the device is precisely driven with feedback control.

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In a precision positioning stage of an electronic device manufacturing equipment,the mechanical resonant mode changes during transference or re-assembling of the equipment.We propose a notch filter design method in this paper that suppresses the positioning performance change by focusing on the mechanical resonant mode change.This method is also effective at suppressing the servo characteristic difference caused by the positioning coordinate in stages that have a large movable range.We conducted simulations to confirm that the positioning performance when the mechanical resonant mode changes.It was less than 3% that the difference between the original performance and one which was using this method.

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For increasing HDD storage density,it is necessary to suppress the high-frequency external vibration of HDD case to enhance the head positioning accuracy.So this paper examines the external vibration isolation of the 2.5 inch HDD in the case of 3.5 inch HDD size by using passive/active mounts.First, external vibration is absorbed by passive mounts connecting HDD and outside case.Then the vibration suppression is enhanced by active control using active mount. Finally,the vibration control performance is evaluated by finite element simulation,in which the location of active mount is optimized by applying particle swam optimization.

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In general,model-based control theory is applied to design control system.In this case,an accurate vi-bration model of the system is required to achieve an adequate vibration control performance.However,making an accurate model and designing a control system increase the workload of engineers,and installing sensors to detect structural vibration obstructs a cost reduction of control system.In this study,we con-sider a self-sensing vibration control strategy using a single degree-of-freedom voice coil actuator without the model of target structures.We conducted simulations on system plant constructed from actuator and target single-degree-of-freedom structure.The simulation results showed the proposed method can achieve vibration control without plant model and sensors.

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Abstract As a method to generate a feedforward input that achieves high speed and high precision positioning,a polynomial-input-type final-state control has been proposed.This method can generatea feedforward input that which drives an initial state to a final state in a finite time.However,the existence of the solution is not always ensured for any initial and final states.To solve this problem, a final-state control method using a polynomial and time-series data has been proposed,though,it requires an extra memory to store the time-series data.In this research,we propose a method that does not require the time-series data by introducing a negligibly-sinall final-state error.The effectiveness of the proposed method is verified by performing simulations.

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A new and simple coupling method between mechanical dynamics analysis and modal synthesis with quasi-constraint technique is proposed.A coupling analysis between mechanical dynamics and modal synthesis is promising for development of imaging machine with transfer belt modules.The driving speed of the belt must be controlled constant value.Though,the belt speed can be run off from the value that caused by unissued vibrations in the system.For stable belt driving control,it is necessary to specify characteristics of whole vibrations in the system and to design control logic with tolerance toward the specified vibrations. Difficulty in using coupling analysis is that coordinate system of two coupled analysis methods is different in general.Our proposed coupling method can be applied to imaging machine vibration problem without such difficulty by using high-stiff spring model.The results of imaging machine vibration analysis using the proposed method are also explained.

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This paper reports on the hardware configuration,control method and experimental results of an Intermediate Transfer Belt(ITB) control system for high-speed color electrophotographic printers.Due to system requirements of fast printing speed,low machine cost,and weight-saving,the printing system must handle increasing disturbances and uncertainties.Thus the ITB control system needs to suppress the periodic and non-periodic disturbances to realize high performance with to keep robustness.The periodic disturbance is caused by mechanical errors e.g.,the belt thickness variation and shaft eccentricity.The uncertainties include mechanical parameter variation,and electrical parameter variation.The belt speed error caused by the mechanical error can be detected by the rotary encoder and belt encoder.We have designed and developed minor and major loop controllers using the three-inertia plant model.Performance and robustness of the system have been verified by experiments using a real printing machine.

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This paper reports on the measurement method of vibrations in Hard Disk Drives(HDD) by using Laser Doppler Vibrometers (LDV).In HDD,the flying height of a magnetic head needs to be reduced for high recording density.Flying stability is needed to prevent contact between the head and disk.Furthermore,the magnetic track width also needs to be narrow for high recording density.The Dual Stage Actuator(DSA) servo system is currently being used for high positioning accuracy.In the DSA servo system,a piezoelectric actuator on a suspension is used to actuate the head.In this study,the vibrations of the head and suspension were measured during the PZT actuation and voice coil motor(VCM) actuation. Based on the results,we considered the influences of vibrations for the flying height stability.

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We measured and calculated shock responses induced by stick-slip phenomenon in hard disk drives,and investigated the propagation path.At first,we measured the shock responses using piezoelectric elements and found that the shock propagates as an elastic wave in the top cover at the two velocities of longitudinal and distortional waves.Meanwhile,we calculated the shock responses using the finite element method,and confirmed consistency between the measured and calculated results.Using the simulation results,we investigated the shock responses of the whole HDD structure.As a result,we found that a dominant factor which leads a position error is the elastic wave that propagates from the stick-slip point through the actuator to the head.Also,we found that the elastic wave induces a tilting motion of the actuator.

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When designing a controller of the ball-screw-driven stage,the frequency characteristic of the stage is generally measured with an actual equipment.Thus,the positioning performance of the stage can't be estimated at planning phase.In this study,we proposed a modeling method of the frequency characteristic of the ball-screw-driven stage.In ball-screw-driven stage,not only the stiffness of the screw shaft but mode of vibration of structure affect the frequency characteristic.The proposed method consists of a lumped parameter model of the ball screw driving system and vibration models of structure,and the effectiveness of the proposed model is determined in comparison with experimental results.

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This paper analyzes the static lubrication characteristics of a slider over a running boundary wall with arbitrary local temperature distributions using the thermo-molecular gas-film lubrication(t-MGL) equation.We obtain two approximate solutions:(i) the linearized solution when the temperature deviation is small(τ_w≪1)and arbitrarily distributed(Superposition method),and(ii) the solution when the bearing number is very large(Λ→∞).We numerically calculated the static lubrication characteristics and verified the validity of the superposition method and the solution for Λ→∞.We also calculated the flying characteristics for various temperature distributions produced by laser heating.

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In recent years,the heat-assisted magnetic recording is suggested as the key-technology to achieve the recording density of more than lTb/in^2.In this technology,It may be problem for the depletion of lubricant film to occur by the laser irradiation,because that is heated to high temperature with laser beams.In this study,we focused on the thermal stability of the lubricant film with the different adsorption states on magnetic disks by the laser irradiation.As a result,it was found that the depletion of lubricant films by laser irradiation showed a different behavior from the reduction of lubricant thickness after heat treatment.The lubricant film with only chemical bonding showed lowest depletion by the laser irradiation

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Cleanliness should be important factor for the stable flying of the magnetic head slider in hard disk drives to improve the areal density.Generally,magnetic disk surface are burnished by the burnish slider at final process in manufacturing.However,the burnish sliders sometimes cause scratches on disk surfaces by the contact with disk surface.In this study,we fabricated the burnish slider with the burnishing surface of vertically aligned carbon nanotube,and studied the burnishing effect using that burnish slider.As a result,the patterned burnish slider of carbon nanotube improved the burnishing effect on magnetic disks.

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The design theory of the previously proposed contact head slider was extended by considering the intermolecular adhesion force and thermally protruding head slider.The microwaviness-excited vibration characteristics of the thermally protruding head slider were analyzed by using the JKR adhesive contact theory.An important fact revealed is that.owing to the adhesive force,the excited frequency of the contacting slider are changed from zero to a value higher than the original second mode resonance frequency with an increase in the head penetration depth.This results in the successive appearance of the first and second pitch mode resonances.It is suggested that the region of the head penetration depth for perfectly stable contact sliding can be widened by increasing the contact damping and decreasing the microwaviness.

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In recent years,the light contact recording is proposed in order to reduce the flying height between magnetic head and magnetic disk.But,it is difficult to stably read and write data,because the magnetic head is contacting with magnetic disk rotating at high speed.In this study,we studied the slider vibration in the contact by vibration using 1 degree of freedom model.And,we analytically investigated the effects of the adhesion force between the slider and disk to slider vibration,thickness and viscosity of lubricant layer and roughness of disk surface.As the results,low viscosity lubricant and optimum adhesion force are needed in order to realize the stable light contact recording.

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Perfluoropolyether(PFPE) lubricants are coated on the surface of hard disks or touch screens in order to reduce adsorptions of various contaminations.In this study,the durability of PFPE lubricants with different chemical structures,which have a endgroup at single side of Demnum mainchain(DDOH),two endgroups at both sides of the mainchain(D-4OH),and two endgroups at both sides of Fomblin mainchain(Fomblin Z-tetraol),were evaluated by the reciprocating friction tester.Friction force of Z-tetraol and DDOH showed lower than that of D-4OH and the lubricant depletion of DDOH after test showed smaller than that of other lubricants.Therefore,DDOH showed best durability performance in these lubricants.It is estimated the flexibility of lubricant molecules affects to the durabolity.

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To protect the interface against intermittent head-disk contact in hard disk drives,nanometer-thick perfluoropolyether(PFPE) films consisting of both "bonded" and "mobile" molecules are applied on the disk surfaces.Molecules retained by the disk after a solvent rinse is defined to be "bonded",while those removed from the disk is defined to be "mobile".Because of their different adsorption states and mobility,the bonded and mobile molecules are supposed to contribute differently to friction properties,which directly impact the stability of ultra-low flying head-disk interfaces.Here by measuring the friction force at light loads and high speeds as a function of bonded and mobile film thicknesses,we studied the contributions of bonded and mobile molecules to the dynamic friction of nanomer-thick PFPE films.We found that mobile lubricant molecules generally tend to decrease friction while bonded lubricant molecules determine the speed dependence of friction.

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To more fully ascertain the functions and structures of target materials will require the coalescing and integration of a wider spectrum of complementary information only obtained by good combination of various quantum beams,and Frontier Research and Development Committee on Highly Coalesced Quantum Beam Science and Technology was set up in Japan Society for the Promotion of Science(JSPS) to create a new,<"Highly coalesced quantum beam">_<_> research domain,developing new complete therapy for integrating various quantum beams,including neutron,x-ray,electron,synchrotron radiation and laser beams against cancer.This paper emphasizes the effectiveness of highly coalesced quantum beam science and technology in cancer,quoting case reports from promise in tests involving tumor model.

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Li_3N synthesis on Li deposition layer was conducted without H_2O and O_2 by in-situ lithium deposition in high vacuum chamber of 10^<-6> Pa and ion implantation techniques and thermo-chemical stability of the Li_3N/Li/Cu tri-layered target under laser heating and air exposure were characterized by X-ray photoelectron spectroscopy.Following conclusions were derived;(l) Li_3N/Li/Cu tri-layered target with very low oxide and carbon contamination was synthesized by in-situ lithium deposition and ion implantation techniques without H_2O and O_2 additions.(2) Build-up of evaporating temperature of Li layer on Li/Cu layer target about 137K was observed by Li_3N formation on the surface of Li layer(3) After air exposure in the early stages,remarkable oxidation and carbon contamination were observed on the surfaces of Li/Cu and Li_3N/Li/Cu,respectively.These contaminated elements on the surface of Li_3N/Li/Cu were not removed by Ar heavy spattering.

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This paper proposes a simple sensor systems development method for supporting elderly people,and the constructive method of a community using it,and verifies these significance and reactions of people involved in this pilot program.We have developed the sensor system with excellent cost performance by using a magnetic sensor and the Internet E-mail for the elderly single population.This sensor unit is able to interact with weak radio.If the behavior of the elderly is not detected a long time,each sensor unit which is installed at the entrance of each room flashes LED of all sensor units to communicate with each other.These illuminations disseminate noticeable information of the abnormal state of the elderly to neighbors and passers.At the same time,this system wll notify by e-mail in real-time to support staff and officials.Major role of this system behave as a trigger to widely contact a network of community members.

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This paper presents a method to estimate a three-dimensional(3D) trajectory and posture of lower limb during jumping motion using inertial sensor.Longitudinal direction of lower extremity and trunk are estimated from posture of sensors which are updated by integration of angular velocity and posture of lower limbs is constructed by connecting joints of each segment.Pressure sensor located under heel is used to identify the position of foot on the ground or in the air.When the foot touches on the ground,posture and position of body are calculated in sequence from the foot to the other one via trunk.When both feet are apart from the ground,position of trunk is estimated by double integration of body acceleration.One subject performed vertical and standing long jump and estimated posture is compared with the actual one obtained using optical motion capture system.

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The superficial skin tissue makes up of complicated layers and micro-structures,associated with water content,which should determine micro mechanical properties resulting in viscoelastic behaviors.Recently,OCT has been being developed as a cross-sectional imaging tool with 1 to 10 micrometer resolution.Authors have developed Dynamic OCSA,which can provide time- and space-dependent distribution of tissue deformation by means of direct cross-correlation technique.In this study,the proposed method was applied to skin phantom "BioSkin",in order to confirm the detection of internal viscoelastic information.As a result,Dynamic OCSA can identify statistical significance of viscoelastic properties,i.e.creep recovery time.It is,therefore,concluded that Dynamic OCSA could employ as a "Micro Mechanical Skin Biopsy".

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Skin is considered to be the reflection of one's health,and therefore,monitoring skin condition is important in diagnosing an illness.Palpation is a physical examination,which involves examination of the skin condition by using feeling of touch.The issue associated with the palpation is that it is subjective and therefore causes difficulties such as repetition and exchange of information.To deal with this,sensor systems capable of measuring the skin condition in various parts of the body are demanded.The previously developed sensor system was able to measure both roughness and stiffness of the human skin but not simultaneously.In this paper,a handheld haptic device,focusing on simultaneously measuring the roughness and stiffness of the human skin is developed using a PolyVinylidene DiFluoride(PVDF) film and strain gauges as sensory elements.

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In Japan,midwives perform Japanese hands-on(perineal support),which is important to prevent perineal tears and to deliver safely.However,it is difficult for trainee midwives to acquire the procedures.Therefore,the advanced delivery simulator that enable the midwives to evaluate the skill objectively is demanded.In this paper,for realizing the delivery simulator,we focus on the pressure of midwives' fingers and palms during Japanese hands-on.Fundamental experiments were carried out using flexible pressure sensors.In experiments,six experts perform the Japanese hands-on using normal delivery phantom.From the analysis of pressure profile,the cooperation between the left and right hand was investigated.

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The experimental device was set up for measuring human's joystick operating force.The joystick was fixed on a table and test subjects sat on a chair and operated the joystick to the sound.Test subjects listen to white noise output from a speaker.We have established an acoustic control system that feedbacks operating force for realizing target value of joystick operating force.Firstly,we have tried to use the neural network to shorten the time for calibration of human.The duration of this calibration is 9 seconds.Compared with the time duration of calibration in the PI control reported in our previous study,the time for calibration experiment considerably decreased.We conducted a constant-value control experiment using acoustic control system with neural network right after calibration experiment.The neural network methods we applied have better characteristics in the constant-value control experiment than PI control method.

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This is a preliminary- study on new warning method for the Human-Machine-Interactive operation environment.Human's operation under hearing same beat sounds are paid attention.Relationship between frequency of beat sounds and human's operation are analyzed.In his experiments,easy to express the human operation,Uchida-Kraepelin test are performed.The results of many experiments performed with a different beat sound show that performance of Uchida-Kraepelin test will be changed unconsciously shortly after beat frequency changed.

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Firstly,we have conducted experiments of operating a joystick to the sound.Test subjects listen to white noise with square envelope.and the white noise that sound level fluctuates on sinusoidal wave.During the experiment,operating force of the joystick and integrated electromyogram(IEMG) were measured.In this experiment,we showed that IEMG has better characteristics than force operating joystick.Next,we investigated the influence of the visual stimulus of bar moving periodically up and down.Compared to the visual stimulus,sound stimulus showed good characteristics.

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We examined haptic hand-motion perceptual performances among the following four perceptual modes by psychophysical experiments:(1-a) CoAc-mode(cutaneous-combined-proprioceptive active),(1-b) CoPa-mode(cutaneous-combined-proprioceptive passive),(2-a) PrAc-mode(proprioceptive active),and(2-b) PrPa-mode(proprioceptive passive).From the viewpoints of systematic and random errors,statistical test results suggest that two factors,sensation and initiative,almost independently contribute and additively enhance performance.We also quantitatively determined the contributions of additional cutaneous sensations and individual initiative in haptic length perceptions and found with haptic directional perceptions that persons perceive moving directions with trigonometric systematic error and random error by a root mean square error of 18 to 19°.

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Many kinds of wearable robot such as power-assist robots have been proposed.Those robots are useful for the elderly or physically weak persons.To reflect a user motion intention to the motion of the robot,biological signals are used as input signals for the robot.An EMG signals one of the widely used biological signals.However,a person who cannot generate EMG signals is not able to use those robo ts.0n the other hand,in recent years,EEG signals are used as input signals to control the robot.Those robots can be used by persons even if their EMG signals cannot be measured.In this study,EEG signals are used to control a upper-limb power-assist robot.To use EEG signals as input signals for those robots,it is necessary to estimate a user's motion intention from measured EEG signals.In this paper,certain EEG channels are selected and the hand velocity is estimated based on selected EEG signals.

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We propose an approach to damage identification of structural system by means of a multi-layered neural network.The approach is based on the change in dynamic characteristics caused by the damage of the structural members.The relation between the damage and the dynamic characteristics is implemented with a multi-layered neural network;the error back-propagation with fixed connection weight is adopted to solve the inverse problem for the damage identification.Numerical experiments with truss structures are conducted and the feasibility of the proposed approach is discussed.

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This study aspires realization of eye-gaze tracking to provide human instructions to robot through eye-gaze In recent years,although the eye-gaze detection study becomes active,its accuracy doesn't enough to provide instructions to robot.Furthermore,since detection of eye is easily affected by light fluctuation,there are many special devices capable of measuring the eye-gaze with high accuracy.Hence,this study's objective is derivation of new algorithm.which doesn't depend on external device.To realize this objective,we detect the eye-gaze using general-use Web- camera to obtain image and perform image processing using OpenCV Especially,we produce a new iris-detection method.which is used for the eye-gaze detection as a key technology.Since in 40 trials average brightness of true inner circle is less than one of false iris inner circles in probability of 97.5%,this new algorithm is available for the eye-gaze detection.

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Probe car system consists of probe cars,a center and control cars.The probe car is the vehicle equipped with sensors,GPS and communication devices.The probe car collect the road traffic information and send it to the center of the system.The center calculates the optimal velocity of each vehicle from the information and deliver the optimal velocity information to control cars.Control car control the velocity as close to the optimal velocity.In this study,the effect of the probe car system for solving traffic jam is discussed by the simulation.The simulation model is based on cellular automata model and velocity control model of actual traffic data.The vehicle movement follows the stochastic velocity model.Traffic flow on one-lane straight road is considered as an example. The results showed that use of the present system enables free traffic state at higher traffic density and that,however,the effect of the present system depends on the density of the probe cars.

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