This paper deals with the countermeasures for pattern formation phenomena in a hot leveler. The modal analysis was applied to the system with time retardation by wear in order to obtain the equations of motion for each mode and some important parameters were derived. The characteristic roots of this system were treated analytically and approximately and the influence of the parameters for pattern formation phenomena was investigated, compared with the exact solutions. Furthermore, the countermeasures by changing the operating speed in a small way were studied by applying numerical simulation. As the results, it was confirmed that the growth speed of the pattern could be delayed by changing two operating speeds alternately. The optimum changing method of the operation speeds was also studied.

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In a previous paper, to clarify features of the sound field of a structure-acoustic coupling system, a rectangular parallelepiped with a flexible panel at one side is analyzed. From a practical view-point, a parallelepiped with many flexible panels is also important. In this paper, a rectangular parallelepiped with two flexible panels in opposite sides is considered. First, experimental study is conducted. Two features worth noting are found. One is that there is in the response curve two fixed points, which is unaltered by a modification of the structure. The other is that the sine modal shape can exists, whose existence is confirmed in the usual structure only when its both ends are open. Then, theoretical study is made using a one-dimentional mathematical model. It is found that this model can explain the features mentioned above.

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This paper considers the minimization of total acoustic power radiated from a large duct opening. The authors propose a method employing an active noise control in order to minimize the total acoustic power by designing the duct opening, leading to change the complex pressure amplitude in the duct opening. This method was applied to the transformer noise radiated from a large duct end. The experimental result was confirmed by comparison with the simulation result.

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In recent years one-box-cars are very popular in the market. So their interior noise level is required to be the same as that of passenger cars. To find an effective way to reduce the noise level, we studied why the noise level is high in a one-box-car as compared with a passenger car. We found that, because the diesel engine is placed under the front passenger seat, only narrow space is allowed between the engine and the engine cover, and this narrow space amplifies the noise. We confirmed by numerical simulation that this conclusion is appropriate. Based on the conclusion, we proposed to set up a silencer to lower the noise level, and found that it works effectively.

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Suspension devices with histeretic nonlinearity like functional rubber pads have been dealt by models with types like bilinear, trilinear, Ramberg-Osgood, Wen characteristics, by which sufficient adaptation of parameters to those measured from the devices has been difficult. A method is proposed which makes it possible to discribe of the hysteretic nonlinear characteristics obtained from dynamic property test of the actual elements in terms of Preisach model. This makes it possible as well that vibration analysis of mechanical system with hysteretic nonlinearity baned on measured property of actual elements.

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This paper presents a synthesis method of nonstationary robust controller considering uncertainties of time-varying object such as variation of parameter and spillover due to ignored high order modes of object. The variation of parameter is experessed by a scaled structured uncertainty in the time domain. Meanwhile, the influence of spillover is given as a unstructured uncertainty in the frequency domain. In this research, a nonstationary robust vibration controller considering both uncertainties is designed by solving a time-varying Riccati equation derived from a differential game type criterion function. The proposed control method is applied to the transverse vibration control of wire changing its length. Through numerical calculations, the reduction performance of the proposed controller is verified and the advantage with respect to the robustness for the uncertainties is demonstrated.

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Making a vehicle lightweight for high-speed often leads to reduction of flexural-rigidity of the body, and it brings about a problem that elastic vibration deteriorates ride quality with rigid body vibration. In addition to the rigid body vibration, it is also necessary to reduce the fundamental elastic mode of body bending vibration in order to achieve good ride quality. In this study, a FEM model is made by taking into consideration not only the rigid body dynamics, but also the elastic body vibration of a railway vehicle, and the effectiveness of semi-active suspension is examined for the elasticity vehicle. The semi-active suspension designed by the bilinear optimal control theory is used as a means of vibration reduction. The bilinear optimal control theory is applied to the suspension and it is compared with the skyhook control theory which has already been put into practice. As a result, it was shown that the bilinear optimal control theory reduces elantic vibration as well as rigid body vibration, while the skyhook control theory can reduce only rigid body vibration. Particularly, it was made clear that the semi-active suspension located at the truck can control the elastic vibration of vehicle body.

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The container crane of the harbor received the enormous damage in the Hanshin Awaji great earthquake disaster. After that, the container crane with seismic vibration isolation system has been developed and operated in practical use. We proposed the rocking type of vibration isolation sysem (RVIS) for the container crane instead of the horizontal type of vibration isolation system that is used in bridges and building. It was found that the damping factor of RVIS mechanism has the particular values for the different natural vibration modes. In this paper, we propose the application of a semiactive control system to the RVIS mechanism to improve the isolation performance and operation efficiency. The Kalman filter in used to estimate the system state values. The results of the isolation controlled by the semiactive system are better seismic isolation in performance than the passive RVIS. And we show that the semi-active RVIS can be used in the operation of the container crane.

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On sharp railway curves as those that are rare in mainlines, the wheel lateral force of rail vehicles increases due to the growth of attack angle and causes the heavy wear of both wheel flange and rail. This paper deals with the curving performance of an active steering vehicle that is converted from a self-steering one by replacing the damper in the longitudinal axle supporting mechanism to an actuator. MBS software SIMPACK is employed for the simulation. Simulation results show that the active steering system has a potential to reduce the lateral force even in sharp curves the radius of which is less than 200 m, while the original self-steering vehicle cannot achieve the reduction. It is also indicated that the running stability of the vehicle with proposed active steering mechanism does not lower from the self-steering condition and the control force generated by track irregularity does not become large up to the level that increases the running vibration and wheel lateral force on tangent track.

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This paper deals with a rail vehicle the wheelset of which has a clearance in the rolling direction. Numerical simulation is employed directly considering the clearance, which exists in the spline between the wheel and the axle, to analyze the dynamic characteristics. Simulation results show that the existence of clearance makes the wheelset rolling vibrate in a limit cycle oscillation. Then, generation mechanism of the limit cycle is investigated as well as the influence of the expanded clearance, which is due to the wear and deformation by long-term use, on the limit cycle. Moreover, it is shown that the use of higher equivalent conicity of wheel tread is desirable to reduce the flange contact by the limit cycle oscillation under existence of track irregularities.

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In order to reduce the number of conventional support devices for the piping system, such as oil snubbers or mechanical snubbers, consequently to reduce the plant cost, various kinds of high damping supports have been developed. As one of these high damping supports, the authors have developed a rotary type lead extrusion damper, and investigated the energy absorbing characteristics and the seismic response reduction of piping systems through the fundamental tests and large scale 3D piping system tests. In this report, the relationships between the energy absorbing characteristics of a rotary type lead extrusion damper and seismic response reduction of piping systems are summarized and clarified. Furthermore, in the view point of damper functional integrity, the relationships between the accumulated absorbed energy and the piping system seismic response were discussed, and the important items in designing the piping system supported by lead extrusion dampers are summarized.

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The Hyogoken-Nanbu earthquake occurred in Kobe area of Japan in 1995. Considering the lessons learned from the disaster, the National Research Institute for Earth Science and Disaster Prevention (NIED) is now constructing a three-demensional full scale earthquake testing facility. In order to develop new control and operation methods for shaking tables with time-varying test models, we have studied dynamic interaction between a shaking table and a bi-linear test model by using the two-demensional small shaking table of NIED, and applied MCS algorithm procedure, one of the model reference adaptive control methods, to the system for studying the efficacy of the procedure. Satisfactory results were obtained from this study.

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This paper deals with harmonic oscillations in a nonlinear two-degree-of-freedom system in which natural frequencies are comparatively close. Six kinds of approximated differential equations are derived and the bifurcation analysis are performed using these equations. By comparing the results of theoretical analyses with the results of the numerical simulation, it is clarified that the 2nd-order approximation in the method of multiple scales using the modified detuning parameters is the best approach to analyze the vibration characteristics of this system with a high accuracy. As a result, it is found that undergoing Hopf bifurcation the periodic solution experiences period doubling bifurcations and results in chaos, and that the bifurcation points obtained by this method are in good agreement with the results of numerical simulations.

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Vibration of the saw wire traveling through the laser irradiation device and the water cooler is analyzed with dynamic stiffness matrix method. This method derives the equation of the complicated system by assembling the dynamic stiffness matrices of the finite number of sub systems. Interaction between the wire and the water in the cooler are formulated using the parameters such as fluctuating drag coefficient and the added masses, which are identified on the experiments. The validity of the proposed method is examined on experiments.

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Flexural vibration of the beam is studied using Cellular Automata Method (CA). Local rules of flexural wave propagation are derived analytically. Assuming the initial displacement of the beam to be impulsive wave, deformation pattern of that wave is calculated for progressive wave after one sampling period, and that pattern is considered to be the local rule of the flexural vibration. The deformation pattern is expressed like finite impulse response filter h(x), so convolution of flexural wave along x-axis is calculated at every sampling time. Transfer functions of displacement between two points along the beam are calculated by CA when progressive wave traveling, and are compared with analytical one. Both amplitude and phase are agreed with analytical one. The local rule of reflection at simple support boundary are also derived. Then resonant frequency of the simple support beam are calculated by CA. There are also good agreement between CA and analytical one. The good agreements suggested that the local rules of flexural wave are sufficiently reliable.

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In order to investigate the severe slider vibrations and hysteresis behaviors of touch down and take-off processes in near contact regime, we numerically calculated the slider dynamics by using the 2-DOF model considering asperity contact, adhesive force of lubricant and friction force. As a result, we could find friction-induced vibration as follows : In the touch down process, the slider exhibits bouncing vibrations as the slider contacts with the disk surface. In the take-off process, the slider continues the bouncing vibration even if the nominal flying height becomes higher than that when the slider begins to contact with the disk surface. These bouncing vibrations and hysteresis phenomena are observed only when both lubricant force and friction force exist. In addition, the bouncing vibration is not simply periodic but contains many frequencies. From spectrum analysis of the slider vibrations up to 1 MHz, we can observe the many super harmosics and sub-harmonics. These analytical results agree well with the experimental ones. As a result, we can say that the severe contact vibration is a self-excited vibration of the slider related to both lubricant force and friction force.

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Elastic impact and contact of spheres are frequently encountered in the field of engineering and science. It is usually treated by the Hertz theory of impact. It is regarded in common that the theory can give the solutions in good accuracy in the case of low speed impact. However, the theory contains the assumptions in which the dynamic effect is ignored and the deformation of spheres is limited in the vicinity of the contact region. In the present paper, elastic impacts of two equivalent spheres are analyzed by using the Finite Element Method (F. E. M.). At first, the elastic dynamic deformation of the sphere is investigated. Then the results from F. E. M. and the Hertz theory of impact are compared. Finally, the equations for maximum deformation of sphere, maximum contact force, contact duration and maximum contact radius are presented. These equations are not only able to calculate accurate solutions for elastic impact of two equivalent spheres, but also useful to evaluate the errors in the solutions obtained from the Hertz theory.

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The experimental study of conductor-insulation separation has been performed by means of a vibro-electrostatic separator. The separator consists of a vibratory feeder equipped with two plate electrodes. The separation tests were performed on a sample containing 50% polyvinylchloride (PVC) and 50% aluminum. The influence of electric field strength and amplitude of conveying surface on the separation efficiency was investigated. The purity of PVC was 99.18±0.05% at the recovery of 93.11±0.91%. The purity of aluminum was 99.72±0.07% at the recovery of 90.65±0.79%.

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This paper presents a method for robust nominal model matching control for nonminimum phase continuous-time systems in the presence of unmodeled dynamics. This scheme can robustly control the nominal model in the presence of unmodeled dynamics and achieve the desired model matching simultaneously. Furthermore, the sufficient condition for stabilizing the nominal model in the presence of unmodeled dynamics is derived and the existence of bounds for all signals is proved. Finally, computer simulation results are presented to show the effectiveness of the proposed method.

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In this paper, we propose a robust adaptive control for uncertain nonlinear systems via backstepping procedure based on high gain feedback strategy. It is shown that one can design a stable adaptive control system provided that the uncertain nonlinearities can be evaluated by an unknown constant and a known nonlinear function which give upper bounds of uncertainties. The effectiveness of the proposed methods is demonstrated by a simulation for a CSTR model.

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H-infinity control theory is applied as a systematic design method in order to ensure robust stability against large variation in characteristics under vehicle operating conditions and variation in friction characteristics of the torque converter lock-up clutch induced by aging deterioration. In this theory the robust stability for the characteristics variation is guaranteed by "small gain theorem". However, since the theorem cannot guarantee the system to achieve sufficient stability margin for all uncertainty in practical use, transient characteristics may be not good. In this paper, from a viewpoint that the transient characteristics in the perturbed conditions are specified by the cosensitivity function T(s), we improve the transient characteristics with a method of doing loopshaping for T(s) in order to be obtained in the adequate shape. The results of simulations show that the designed controller keeps sufficient stability compared with that of the PID controller.

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In previous paper, H-infinity control theory was applied in order to establish high reliability of a torque converter lock-up clutch slip control system. In this paper, evaluation test on vehicle is done after the controller is transformed so as to maintain the designed characteristics for implementation into an onboard ECU. As a result it is confirmed that robust stability against large characteristic variation under vehicle operating conditions and variation induced by aging deterioration is ensured. However it is found that there is a limit of improvement in performance with the controller adopting fixed gain because of the large variation in the system. So we propose "characteristic variation compensating filter" which compensates for the variation with only a few parameters in order that the characteristics of plant realized by feedback controller become invariant, so that the high performance can be achieved. The result in the system shows that the proposed filter makes the performance improve several times.

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In the present paper, we examine a design for repetitive control systems with multi-period repetitive compensator. The repetitive control system is a type of servomechanisms for periodic signal. The repetitive control system is a neutral type of time delay system and can not apply for strictly proper plants. Almost all plants are strictly proper. Several modifications of repetitive control system for strictly proper plants are proposed. One of them, it is well known that the modified repetitive control is easy to apply for strictly proper plants. Sugimoto and Washida point out that if time-delay is settled to cancel the phase angle of low-pass filter in the repetitive compensator, then the disturbance attenuation characteristics is improved. However, the method by Sugimoto and Washida improve the disturbance attenuation characteristics in only low frequency range. Generally, the disturbance includes variable frequency signals. In this paper, in order to attenuate the disturbance with higher frequency range, we overcome this problem and propose a design method for repetitive control systems with multi-period repetitive compensator. In addition, a design method for repetitive control systems, which is stable, is given.

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In the present paper, we give explicit parametrization of all causal stabilizing repetitive controllers for single-input/single-output continuous time certain class of non-minimum phase systems. The parametrization of all causal stabilizing repetitive controllers was first studied by Hara and Yamamoto. Katoh and Funahashi give the parametrization for the class of all stabilizing repetitive controllers for minimum phase biproper plants by solving the Bezout equation explicitly. However, Katoh and Funahashi assumed the plant is asymptotically stable. Using parallel compensation technique, Yamada and Okuyama gave explicit parametrization of all repetitive controllers for minimum phase systems that is not necessarily stable. We expand the result by Yamada and Okuyama and give the parametrization of all causal stabilizing controllers for certain class of non-minimum phase systems. Finally, a numerical example is used to illustrate the effectiveness of the proposed method.

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These days, requirements of functions tend to spread and the designers need to treat problems as multi-objective optimization. However, decision making through multi-objective optimization is not that simple and we need to give preference of the designer to give a solutions, which has been done through local information called trade-off ratio. Usually, trade-off ratio and the results does not have linear relationships, thus it is quite hard to give desired trade-off ratio in a few steps. In the case there are a few objective functions, we can visualize so called Pareto solutions. Then, the designer can grasp the whole relationships of objective functions and it is useful information, something like a map in exploring. For that purpose, multi-objective genetic algorithms are quite powerful tools, and there are tons of studies for it. We have been proposing a method to use Data Envelopment Analysis as estimating Pareto Optimality. In this study, we use Genetic Range Genetic Algorithms, and give a new range around obtained Pareto solution and between them. In order to show the effectiveness of the proposed method, we showed some simple example with and without ill setting.

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As the most of the problems is engineering design are the mixed variables with discrete and continuous variables, Gas is thought as a suitable tool for solving these difficulties. However, Gas has a problem in expressing continuous variables ; therefore it is not as effective as they are thought. There are a number of studies in Gas that treat expression of continuous variables. Most of them did not use G-type expression to make sure accuracy of variables. Indeed, it seemed difficult to make sure accuracy of variables by using binary expression of G-type expression, we have developed adaptive range genetic algorithms, which change searching range for each generation by using information of convergence and solve these problems. However, searching range changes each generation, so that it does not have stability in searching. Therefore we needed to introduce some system parameters and rules to keep it stable. In the previous study, we introduce a new concept of inheritance of searching range and get rid of the stability of searching range problem. In this study, we propose a new method of setting searching range so that it has both minute search to raise accuracy and global search for global optimization.

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Recently, it became popular to do rehabilitation using a high-performance training machine. Especially isokinetic exercise is effective in a clinical test and a training evaluation because of an uniform motion. Conventional training machines have several disadvantages. (E. g. the high cost for a safety system, the limit of acceleration and so on.) Because of them, acceptable training/evaluation speed is not more than 400 [deg/s]. Therefore we suggest the isokinetic exercise system using an ER brake. Response time of this brake is about 5 [msec]. It is possible to reduce the inertia of the system by using it, and training speed can be improved. We need not to be concern about an overdrive. It becomes very safe system. As the result, we realized the velocity control over 800 [deg/s].

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In this study, a precision stage constructed of the electromagnetic actuator using the rubber film has been developed. We have proposed the hybrid rubber-electromagnetic actuator (RE actuator), which has the following features. (1) Viscous damping is essentially obtained by rubber. (2) The actuator functions also as flexible joint. (3) Since there is no sliding guide, precise positioning can be performed. An an application of this actuator, the XYZ precision stage has been developed. The feature of this stage is that it can be driven in the XYZ direction in spite of the monolithic structure. And it is also one of the features that residual vibration does not occur after positioning. Fundamental properties of the stage are investigated, and experiments show the 20 nanometer positioning and tracking a spiral orbit.

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In this paper, we discuss about how to control an object position for ambiguous degree expression in voice instruction ("i. e. Move it a little. or Lift it more."). Man-machine interface with voice information has been attracted considerable attention, because it is one of easy and friendly method for human to operate a machine system. However in order to perform a required task successfully, a machine system has to estimate adequate value for each ambiguous expression. Therefore we analyze how human moves the object for some kinds of ambiguous degree expression in voice instruction. From this result, we obtain a model which can calculate the movement displacement for a given degree expression. Experimental results show our model can lead the object to target position with several times of instructions as human does.

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In recognition of human emotions and KANSEI, facial structure and expressions are the most important information source, but there has been no software to analyze them, probably because image processing of facial expressions are quite difficult. Therefore, we have developed a software which can extract outlines of each facial parts, eyebrows, eyes, mouth and nose robustly and precisely, on Microsoft Windows 2000/XP, and add an automatic extraction function of facial organ outlines using an API (Application Programming interface) which is standard for Windows.

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This paper presents a novel methodology for steering a cooperative a transportation system with two car-like mobile robots coupled together by a carrier. The system is a three-input seven-state drift-free nonholonomic mechanical system. The three control inputs are the moving velocity of the first mobile robot and the steering angular velocities of the two mobile robots. The seven states are the positions of the first mobile robot along the x- and y-axes, its steering angle, its orientation, the orientation of the carrier, the steering angle of the second mobile robot, and its orientation. We first convert the system into two-chain, single-generator chained form, based on a differential geometrical approach. We secondly show a control method of the system by polynomial inputs developed in such chained form. The validity of this conversion and control method is verified by computer simulations performed on driving this cooperative transportation system into a garage.

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The radiation test of a commercial 16 bit-MPU was conducted for the application to the onboard computers of small satellites. This MPU is commercially available and equipped with flash EEPROM, SRAM (4 kbyte), A/D-D/A converter, serial communication interface and peripheral I/O functions. To predict the error rate by the radiation in space environment, a preliminary test was conducted using a Californium-252 radio isotope source at National Space Development Agency of Japan (NASDA), and the tolerance of the MPU was confirmed. As a next step, a radiation test using a large accelerator was conducted at Japan Atomic Energy Research Institute (JAERI), and the error rates of SEU (Single Event Upset) and SEL (Single Event Latch-up) were evaluated precisely. The calculated result by CREME software showed relatively low rates of SEU and SEL in the space environment of the orbit at an altitude of 450 km.

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It is necessary to clarify the roadside air pollution mechanism caused by exhaust emissions from running vehicles. In order to analyze its mechanism, simple simultaneous on-board measurement system for road infrastructure, traffic conditions, vehicle running behavior, driver's operation and actual exhaust emissions based on distance was developed. The measurement system was installed in a light duty freight vehicle. For demonstrating accuracy of the exhaust emission measurement system, tests on chassis-dynamometer that include steady state and transient cycles, and tests on actual road were conducted. The results of tests on chassis-dynamometer showed enough accuracy to evaluate NO_X emissions from a vehicle at local roadsides by optimizing the attachment position of sensors in the exhaust line. In the actual running tests, it was demonstrated that the developed system was effective to evaluate NO_X emission from a running vehicle at local roadside, and also to analyze local roadside air pollution caused by running vehicles.

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A new method is proposed in the present research to estimate thermal deformation of machine tools. The present method utilizes available information in CNC units instead of external sensors such as thermocouples and strain gages. An estimation model utilizing transfer functions and a method to identify them are developed, and it is applied to estimation of the thermal deformation of a machining center caused by rotation of its main spindle and feed motion of the tables. The transfer function matrix between the thermal displacements and the heat generating factors, i. e. rotational speed, primary motor current and secondary motor current, is identified by the impulse response method. The thermal displacements are estimated by employing the identified transfer function matrix while the main spindle and the feed tables are driven at various speeds. It is confirmed by the experiment that the estimated displacements agree roughly with the measured ones.

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Welding is widely used for construction of many structures. It is well known that residual stress is generated near the bead because of locally given heat. Tensile residual stress on the surface degrades fatigue strength. Some reduction methods such as heat treatment and shot peening are practically used. Authors have proposed a new method for reduction of residual stress using vibrational load during welding. In this paper, random vibration is used as vaibrational load considering noise added to input signal. White noise is used as random vibration. Two thin plates are butt welded and residual stresses near the bead are measured. It is found that tensile residual stresses near the bead are reduced when random vibration is used as vibrational load during welding. The proposed method is examined by simulation method using analytical model of the specimen. From the simulation method, it is demonstrated that tensile residual stresses near the bead are reduced when random vibration is used as vibrational load.

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This work presents and discusses the result of sliding wear tests under the boundary lubrication condition with two kinds of white metal, JIS WJ 2 and WJ 7. They are widely used as sliding bearing materials. One (WJ 2) has tin as its main component, the other (WJ 7) lead. The sliding wear tests were performed with lubricant under various compressive stresses and sliding speeds. The log-log plots of the relations between the compressive stresses and the cut off lives are shown by straight lines which differ with sliding speeds. However, there is a unique straight line in the log-log plot between the frictional stress τ and the cut off lives N_f, regardless of the sliding speeds. It was also clarified that the effect of materials on the plot can be eliminated by replacing τ with the non-dimensional stress, τ/σ_cp, where σ_cp is a compressive proof strength (0.125%) of the materials. Furthermore below the critical frictional stress, τ_w no damages were observed.

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This paper deals with a design of the crowning to reduce the ball passage vibrations of a rolling guide with the crowning length L_c (1.2s≤L_c≤1.7s, where s is the distance between the adjacent balls in the load zone). First, a fundamental condition to reduce the ball passage vibrations was provided. Second, a design method of the crowning by applying an approximate curve (an assumed functional formula) to the control points (satisfying the fundamental condition or being the intersection of straight and crowning areas of a raceway) was presented. Third, the design procedure was explained by giving an example. In the example, the power function crowning was nearest the control points. In addition, the calculated amplitude for the power function crowning was lower than those for the circular arc crowning and the crowning of the commercial rolling guide. Finally, the validity of the presented design method through experiments was confirmed.

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Barrel polishing is an extremely efficient processing method for surface smoothing treatment of a large number of workpieces, when performed under appropriate processing conditions. However, workpieces and grinding materials may separate depending on the conditions. Therefore, examination of the processing conditions using dynamic analysis of the behaviors of workpieces and grinding materials is strongly desired. In this study, the behavior of the particles in the planetary barrel that simultaneously rotates around a horizontal axis and revolves around a vertical axis was examined through experiment and analysis using the discrete element method (DEM). The rotary barrel with the cross section of a regular polygon was used. As a result, it was demonstrated that the shape of cross section of the rotary barrel in which power increases even in same combination of two kinds of particles existed.

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Applicability of a conventional and approximated formula of van der Waals pressure for a multilayered system was investigated. It was pointed out that the conventional formula cannot be applied to a general multilayered system and some corrections of Hamaker constants were required according to a combination of component materials in the multilayered system. Then, a generalized and approximated formula of van der Waals pressure for a multilayered system was newly derived. The generalized formula does not require the corrections by the component materials. Applying the generalized formula to an inclined magnetic head slider, dependence of the static load-carrying capacity and limit spacing of flight of the head slider on the PFPE film thickness and attitude of the head slider was clarified.

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General Design Theory (GDT), which was presented by Yoshikawa in 1979, holds the possibility that the object can be also applied to creative arts field in addition to narrow sense artifacts, because the description of GDT is very wealthy in abstract-ability and generality. In the 2nd report, as the extension of GDT, it added Requirement Concept Set to GDT and it modeled in Requirement Space. A Set of the worlds where the concepts produce the possibility to be formed in referring without experiencing entities is named the referable world. By introducing the referable world's Entity Concept Set, a modeling of Requirement Space became possible. Mapping from Requirement Space to Sound Image Space which is formed from the referable world's Entity Concept Set is possible to be also described by Modal Logic. The description of the relation between Entity Concept Set and referable world's Entity Concept Set has the possibility that Mental Space theory can be applied, and referred to the application possibility of Channel Theory to formalize the input and output of a connector in Mental Space.

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In order to know the running-in process for ultra low friction of CNx sliding against Si₃N₄ balls in N₂, the effect of surface roughness of balls on friction coefficient was investigated. As results, it was shown that friction coefficient for all of Si₃N₄ balls decreased with sliding cycles and reached to the specific minimum values less than 0.05. For friction coefficient less than 0.01, smooth surface of ball with 30 nm Ry as initial surface roughness was necessary. Smooth surfaces of CNx coating and Si₃N₄ ball after running-in provide ultra low friction after the transfer of tiny amount of CNx to Si₃N₄ ball and the generating of thin and uniform transfer film on balls.

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In the bag-packing problem, several items are selected so that the sum weight should be closest to the target weight. However, in some cases, the sum weight might be far from the target weight. To avoid such an insufficient outcome, the method of dividing the input materials by a certain weight is proposed. Its weight for division is decided so that the number of feasible solutions should be increased. For each of the divided groups, which items to be included in the contents of a bag is determined. Many of the simulation results seem to prove the proposed method to be effective.

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