One of the main parts of the diesel engine, the crankshaft has the important items related with noise, vibration, and durability. The precise prediction as to these items will be, therefore, useful for understanding the vibration mechanism and for improving these items in an early design stage. This paper describes a new method of predicting these items in operation, by means of several techniques in consideration of the non-linearity in the oil film stiffness and exciting force, applied to the V6 type crankshaft. The accuracy of the simulation is demonstrated by comparing the calculated results with the actual vibration. The visualized simulation results are analytically cleared that the strain at the crank pin fillet is increased by the bending vibration coupled with the torsional vibration.

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In order to clarify vibration characteristics of the horn and capillary system of an ultrasonic wire-bonder, measurements of resonance frequency and mode were carried out with the capillary-tip lightly pressed on simulated work pieces. The results were compared with those in the case of the capillary-tip free, obtained by the previous study, and differences caused by the contact of the capillary-tip with simulated work pieces were made clear. Present and previous results were also considered by theoretical analysis of natural vibration based on a model treating the horn and capillary as beams with tapered portions, and assuming that they were connected at one point.

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Harmonic forced vibration of a spring-mass-damper system with a parametrically excited pendulum hinged to the mass is investigated. Four parameters in the equation of motion of the system are considered. Numerical calculation is used to evaluate the system response. The vibration-absorbing property of the system for the change of the parameters is clarified. Based on the analysis of the vibration-absorbing property, the optimum parameters of the system are obtained.

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In magnetic disk drives, disk flutter due to high-rotational speed causes the increase of the head-positioning error. It is important to clear the mechanism of the head-positioning error caused by flutter. This paper verified the proposed mechanism experimentally and its error was within 10%. The effectiveness of decreasing the transfer function of the head off-track by flutter was also verified experimentally. This paper proposes a slider supporting structure to decrease the transfer function.

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In this paper, the effect of a tuned pendulum damper (TPD) for suppression of the coupled flutter of a super-long span suspension bridge was examined by using a three dimensional FEM model. In the previous paper, using a flutter analysis for a 2 D bridge deck model without horizontal motion, a major effect of TPD on the bridge deck flutter is confirmed. However, it is also clarified that the horizontal force induced by TPD motion brings about the horizontal vibration mode of the deck and the TPD actually loses its ability to control flutter. We theoretically derived a suitable arrangement and mass distribution of TPDs which reduces the horizontal forces. As a result of this method, it was confirmed by a 3 D FEM model that the flutter speed for a 2 500 m span suspension bridge was greatly improved by TPDs.

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Generally an active suspension using an actuator has the most superior performance. But it does not fit common automobile because of its high energy consumption. Therefore an active suspension which can work well by the low energy consumption and achieve the highly damping performance should be studied. To decrease the energy consumption, we propose an active air suspension using low pressure supply driving. By controlling the pressure of pneumatic cylinder lower, it will be expected that energy consumption can be decreased. And we propose to control the pressure supply source by using tank. This tank pressure is controlled minimum as far as the force of skyhook theory is satisfied. This system will satisfy both the highly damping performance and the low energy consumption. The performance of the proposed suspension system is discussed through experiments.

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This paper proposes a new position control method which suppresses the first mode of the vibration of a cartesian co-ordinate type flexible arm. When one-step input is applied to the flexible arm, the vibration of the arm becomes a linear combination of damped oscillations. When the second step input is applied to the flexible arm, if we choose properly the magnitudes of the second step and the interval between the first step input and the second step input, the vibration, which is generated by the first step input, can be suppressed by the vibration caused by the second step input. From the results of computer simulation arid of the experiment, the first mode of the vibration can thoroughly be suppressed by the proposed method. Because the proposed method is based on a feed-forward control, the parameter error affects the controllability. However, it is also confirmed that even if the natural frequency of the first mode varies, the flexible arm less vibrates than the case of no control.

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This paper considers an optimal vibration control of flexible building structures with viscoelastic dampers precisely represented by fractional differential systems. The proposed control system design method consists of three parts. Firstly, it is solved that the optimal regulator problem for the linear dynamical system with fractional differential terms to model viscoelastic dampers. Secondly, an observer for the fractional differential systems is developed to estimate the state variables of this system. These methods have been developed by the authors. Lastly, gain-scheduling control system is developed by arranging the several optimal control solutions for various parameters of viscoelastic dampers, wchich highly depend on the temperature of an environment.

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For an inverted-double pendulum system consisting of an elastic link mounted on a rigid one, its stabilization control techniques have been discussed by using a distributed-parameter modeling method taking the 2nd and 3rd vibration modes of the elastic beam as the residual modes, and by applying such control strategies as an LQ, a frequency-shaped LQ (simply shortened as FSLQ), a sliding mode control (SLM), and a frequency-shaped SLM control (FSSLM), from the viewpoint of the robust stability including the spillover problem. From the real system experiment taking the 1st mode of vibration as the control mode, it is found that even in the FSLQ system, considerably stable control performance can be obtained, while in the LQ system, it is impossible to realize a stable system due to so-called control spillovers. Furthermore, it is demonstrated that the FSSLM has not only the simultaneous suppression effect against the chattering and the spillover components, but also a better robust performance against parameter variations of the controlled system and applied disturbances than the FSLQ system.

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The battery-voltage-driven fuel injector for Direct-Injection Gasoline Engines has an opening coil and a holding coil which enable the injector to operate at the battery voltage, thus eliminating the need for either voltage-step-up circuitry or current-control circuitry. The aim of current work was to increase the magnetic force so as to increase the pressure of fuel injection. It is known that a large magneto-motive force, that is, the product of coil current and coil turn numbers, gives a large magnetic force. However, increased coil current produces more heat as a result. To overcome this problem, we have developed a new dual-coil driving method called the "double-hold driving method". This method enables the current to be fed to the opening coil during the valve holding period. The current is limited to a predetermined value by using a holding coil, which is connected in series to the opening coil, as a current-limitation register. We also inserted a diode into the drive circuit in order to block the reverse current flow caused by the mutual magnetic induction force of the two coils. Adding this diode increased the valve-opening force. It is thus concluded that the "double-hold driving method with a diode for preventing reverse current-flow" enables the injector to inject more highly pressurized fuel without any loss of injection controllability.

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This paper proposes a new type of annular seal named Swirl Braked Grooved Seal (SBGS). The SBGS has circumferential or helical grooves in which several swirl breakers are set up to prevent the circumferential flow. It is expected that these swirl breakers reduce the tangential velocity and the tangential force in the seal. Rotordynamic coefficients and leakage test results are presented for 5 types of the SBGS in the first report. The tested SBGS have 10 circumferential grooves, and several swirl breakers are in all the grooves. The SBGS can reduce cross-coupled stiffness and increase direct damping and direct stiffness compared with the conventional circumferentially grooved seal. The leakage didn't vary according to fins very much. This paper also discusses the difference between the whirl frequency ratio and the effective damping coefficients which are often used for evaluating of seal stability.

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The second report of this study represents the measured leakage, rotordynamic coefficients, and effective damping coefficients for several types of Swirl Braked Grooved Seals (SBGS) with circumferentially or helically grooved stator. The tested SBGS have either 10 circumferential grooves or multi-helical grooves. Several swirl breakers are placed in the 1st and the 2nd grooves (stages) counted from the inlet zone. These swirl breakers are small metallic cuboids installed inside of grooves (per pendicular to the circumferential or the helical direction) in order to prevent the circumferential flows. For the circumferentially grooved stator seals, swirl breakers in the grooves of the 1st and the 2nd stages can decrease cross-coupled stiffness, increase direct stiffness, and have little influence on direct damping and leakage. The stability of the helically grooved stator seals isn't improved by the swirl breakers because of the increase of cross-coupled stiffness, and the decrease of direct damping. The swirl breakers in the helical grooves, however, reduce the leakage very much.

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Recently, direct yaw moment control (DYC) using active brake has been applied on some vehicles. Its control law is determined from result of nonlinear simulation analysis. But, choosing significant inputs to DYC controller is difficult because of nonlinearity of tire-road force. The neural network (NN) can find control law of nonlinear system, but to understand the meaning is difficult because of its complex structure. In this paper, rule extraction from NN controller is presented. The NN controller is obtained by using nonlinear mathematical simulation of double lane change with genetic algorithm (GA). By addition forgetting genetic operator, the connection of NN are reduced and simplified. As a result, simple control law of DYC is achieved. The control law can be implemented by various means because of its simplicity. The DYC control law using side slip angle and time derivative of side slip angle is achieved. This control law has good performance and uses the same inputs as the DYC controller that was obtained by conventional analysis method. As a result, the effectiveness of rule extraction from NN is presented.

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The traveling-wave-type ultrasonic motor (USM) provides unique utilities; compact size, light weight, and high torque at low speed, which evoke its applicability to an actuator of the light weight and compact size robot mechanisms. However, USM pertains a few of problems resulting from driving mechanisms with frictional forces; non-linearity and uncertain characteristics dependent on temperature, which makes it difficult to construct linear control systems. This paper presents a stable control of USM by using sliding mode control, which yields favorable features; controlability of non-linear system and robust stability against uncertainty of system model. A new model besed on the experiment data is exploited for designing torque/velocity servo control system. Though the model contains the uncertainty, the robust stability introduced by the sliding mode control makes the controller compensate the error between the model and the real system of USM. The experiment proves the effectiveness of the sliding mode servo controller.

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In the conventional fuzzy control method, as the value of a scaling factor in the consequent part is the same in all control areas, improvement of the nonlinear input/output characteristics of a fuzzy controller is limited thus, its control performance cannot be improved markedly. Therefore, a new fuzzy control method, which can markedly improve the control performance compared with the conventional fuzzy control method, is proposed in this paper. In the proposed fuzzy control method, the control performance is improved because the value of the scaling factor in the consequent part is tuned dynamically according to the control area by using the fuzzy inference method. Then, on the basis of the simulation results, in which the first- and second-order lag systems with dead time are set as the controlled system, the effectiveness of the proposed fuzzy control method in improving the control performance is compared with the conventional fuzzy control method.

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This paper proposes a levitation control device for a rectangular sheet steel by the hybrid actuator using five electromagnets and thirty permanent magnets. The five electromagnets are independently controlled by feedback signals from gap sensors to stabilize a levitation behavior. The thirty permanent magnets are installed to support the static deflection of the sheet steel. In addition, it is found that the permanent magnets increase the damping factor of elastic vibration and work effectively for the electromagnetic levitation. In this study, the attractive force of the permanent magnets is analyzed by using the finite element method and the elastic vibration of the sheet steel is calculated by the finite difference method. To verify usefulness of the proposed levitation control system, an experiment applying the digital optimal control theory was performed for the rectangular sheet steel (length: 800 mm, width: 600 mm, thickness: 0.3 mm). As a result, in comparison with the system only using the electromagnets, it was confirmed that the control performance was improved by using the permanent magnets.

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In this study, we propose a design method of preview control action for I-PD control system pre-designed with the partial model matching techniques. An optimal preview servo system is used as the model for matching. The proposed control system is decoupled and has similar properties to the optimal preview servo system in spite of using simple control rule. We also propose how to determine the number of preview steps to reduce the steady-state velocity error for ramp reference input. The effectiveness of the proposed method is examined through three numerical simulations.

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A new roll gap checker, which makes it possible to judge condition of roll gaps at second cooling water zone in a continuous casting machine of the iron and steel industry, is developed. This diagnosis system has the advantage of high accurate measurement, durability in difficult surroundings, ease of operation and lack of influence of casting time during measurement. Developed roll gap checkers are applied to continuous casting machines for slab products. Confirmation of measurement repeatability, durability of on-line use over a long period and comparison between actual condition of roll gaps and judgement by using this method are carried out. Good repeatability of measured data, good durability of on-line use over a long period and good correspondences with actual condition of roll gaps are verified. Developed roll gap checkers will be utilized in continuous casting machines of the iron and steel industry, and are expected to contribute to their stable operation and casting of good quality products.

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A three-dimensional measuring system that uses a single TV camera is introduced. By introducing a refractor on the TV camera lens, measuring points, which appear on the image plane, are displaced according to the depth. By rotating the refractor at high speed during the TV camera exposure, these measuring points are shifted and appearted to be circular streaks on an image plane. Since the size of a circular streak is inversely proportional to the depth from the TV camera, the depth can be measured easily by processing the circular image. In the case that the measuring points are dence, streaks on the image plane would be overlapped each other. By generating the lines in the direction of edge normal against the edge of circular steaks, each streak could be extracted from the overlapped images automatically. In this paper, the experimental results of shape measurement of objects and flow measurement are introduced.

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It is impossible to disregard the adverse effect of acceleration on the gas angular rate sensor that detects channel decentering at respective angular rates by means of spraying gas to a pair of heating resistance wires, because such a sensor has characteristics of a large buoyancy caused by temperature distribution. It is an essential condition to set requirements for acceleration compensation, because such sensor, especially compact one, has a characteristic that respective heating resistance-wires are subject to interact each other. In this paper, fluid behaviors for such gas angular-rate sensor are briefly described with respects to both forced convection and natural convection to suggest requirements for gas volume obtaining an angular-rate output without the adverse affect of acceleration. Micromachining sensors with semiconductor process were used as samples under test. This paper also defines the requirements described above, and indicates increasing possibilities to provide accurate, low-cost angular-rate sensors without adverse effect of buoyancy.

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In this report, we attempt to solve the minimum input trajectory solution under the input conditions that the ankle or knee joint is passive. Because we expect to realize the optimal biped locomotion by using fewest actuators to reduce the weight of biped mechanism and to simplify the control algorithm. As a result, we obtained nearly optimal trajectory solution when the ankle joint is passive. When the knee joint is passive, however we cannot get an optimum solution that satisfies, the dynamic constraint condition of the passive joint. Then, we obtained the optimum trajectory solution without knee collision and found that the gait without knee collision consumes more energy than that with the knee collision. Moreover, we calculated the optimal trajectories for various values of stride length and clarified that the optimal stride length is 0.3 m in terms of energy consumption and average speed.

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A path planning method is described for an omnidirectional mobile manipulator by applying an evolutionary strategy. For a path using B-spline, it is important to note how to choose some appropriate data points and the corresponding end points. The proposed approach can automatically select their points in a wide range, minimizing or maximizing the total cost function, which consists of several sub-cost functions such as motion smoothness, movable range of joint singular orientation, falling down and obstacle avoidance. The simulation result shows that our method is useful for the path planning of a robot, which has many constraints and complicated evaluation like a mobile manipulator considered here.

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We are stepping into an aging society rapidly. In that society, it is important that physically weak people are able to take care of themselves. In this paper, we introduce an effective control method of a 1 DOF exoskeletal robot to support the elbow motion of physically weak people. Fuzzy control has been applied to control both the angular position and impedance of the exoskeltal robot system based on generated force signals and vague biological signals that reflect the human subject's intention. Skin surface electromyogram (EMG) signals and the generated wrist force by the human subject during the elbow motion have been used as input information of the fuzzy reasoned impedance controller. The experimental results show the effectiveness of the proposed control method of the exoskeletal robot.

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A robot satellite with dual-manipulator is one of the choices for on-orbit servicing such as capturing damaged satellites in orbit. We have constructed a ground experiment simulator system including two 7-degree-of-freedom (DOF) manipulators as a chaser satellite model and floating testbeds as target satellite models. This system is a tele-operation ground experiment system and consists of the following subsystems: robot system, vision system, manipulator operating system, ground control system and damage satellite model system. Using this system, we will study on feasible capturing and berthing methods of damaged satellites using dual-manipulator. In this paper, we explain the detailed description of the system and reported the results of the basic satellite capturing experiments.

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A whole-body musculo-skeletal model in a sagittal plane and an estimation method of internal loads on sitting posture has been developed. Two-dimensional rigid link model was constructed as 13 segments. These segments were connected with elastic springs imitated ligaments or intervertebral discs. Sixty-three muscles were attached on the rigid links. Intra-abdominal pressure was also considered as a balloon. Using the method, muscle forces, ligament tensions, intervertebral loads, and abdominal pressure were calculated from a measured Sitting posture and seat reaction forces. Calculated results were compared with the measurements by intervertebral pressure and EMG. Using this method, the differences of sitting postures or chair conditions could be quantitatively evaluated by internal loads.

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This paper describes an algorithm for lane departure detection, warning and shift to automated driving with a vision system that detects reference lines including lane markings along which the vehicle drives. Lane departure is detected by comparison of steering by a human driver and that calculated with a vision-based lateral control system. The algorithm is featured by the use of whole data in the field of view of the vision system as well as by preview characteristics, which enables the warning in advance. Simulation studies and outdoor experiments with an automobile have been conducted to show the feasibility of the algorithm.

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Cross-sectional configurations of rail for reduction of rolling noise of high-speed railway; Shinkansen are examined. First, depending on the Timoshenko's beam theory, the random vibration of an infinite rail with various cross sections subjected to the surface roughness excitation is analyzed considering the coupling with one material particle which is the model of wheel traveling on it. Then, the distributions of sound pressures radiated from those vibrating rails on the slab track are calculated based on the Boundary Element Method. In order to evaluate the reduction effects of rolling noise, the line spectrum approximation is introduced, and the radiated sound powers are estimated for seven definite frequencies in the range from 500 Hz to 200 Hz and relative reduction effects in comparison with the standard 60 kg long rail of the present Shinkansen are examined, and the effective rail cross-sectional configurations for reduction of rolling noise are proposed from the viewpoint of acoustic engineering.

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In the case of parallel axis gears (for instance, spur gears or helical gears), it is clear that the variation of tooth error in a gear pair has influence on the dynamic behavior of gears. However, the measurement of tooth error is impossible in the case of spiral bevel gears. Therefore, we pay attention to the tooth bearing as an estimation factor of the variation of tooth error in a gear pair to the spiral bevel gears. In the present report, a color image processing method was used to obtain the tooth bearing of each meshing in a gear pair, exactly. On the other hand, the rotational acceleration of each meshing was measured under running conditions. Comparing with them, it was confirmed that the variation of tooth bearing in a gear pair had influence on the dynamic behavior of spiral bevel gears

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Since one can make a manufacturing process short if a sintered material is applied to parts with complex configurations, reductions in production costs may be expected. Therefore, a gear made by steel powder sintering will be useful for a power transmission gear in automobile when the gear can be burnished using a worm-shaped tool to improve a tooth profile and a surface roughness. In the present study, sintered alloy steel was investigated using a two rollers contact fatigue testing machine to obtain a basic data for a design of gear tooth strength. The allowable surface durability strength of sintered alloy steel was lower than about half that of a melted produced steel (general structure steel). However; it is estimated that a sintered alloy steel gear will sufficiently be applicable to an automobile transmission if its application is limited to a range of a low load carrying capability.

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The purpose of this study is to investigate the influence of shot peening on surface durability of sintered powder metal rollers under a sliding-rolling contact condition. The compressive residual stress, the hardness and the surface roughness of the rollers increased and the pores near the surface of those were deformed by the shot peening. The failure mode of the rollers was mainly spalling. The failure depth agreed almost with the depth where the amplitude A(τ_yz/HV) of the ratio of the orthogonal shear stress to Vickers hardness became maximum. The surface durabilities of the shot-peened rollers were lower than that of the unpeened roller in these experiments. While, the spalling cracks propagated from the sharp notches of the pores deformed by the shot peening. In addition, it can be considered that the shear stress below the contact surface of the shot-peened rollers increases, since the increase of the surface roughness by the shot peening results into the increase of the frictional force between the rollers. Therefore, it could follows from this that the mild shot peening without sharp deformed pore and too large surface roughness should be selected in order to improve the surface durability of the sintered rollers.

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Rippling failure is well known as a plastic flow phenomenon on the surface layer of gears and rollers where sliding and rolling contact is repeated. We have already carried out some experiments using a roller testing machine, and examined the effects of the sliding velocity, the hardness of roller surface and the lubricating oil on the rippling. In the present study, we investigate the difference of the rippling occurrence due to the roller contact condition, that is, the influence of circumferential speed and relative contact position of rollers. Consequently, it is confirmed experimentally that the rippling is generated in the Hertzian contact region, whether the two rollers contact at the same position every rotation or not. Moreover, it is cleared that the generating part and the wavelength of the rippling hardly changed with increasing the load repetitions after the rippling first occurred.

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In many bolted joint structures the mismatch of the thermal expansion coefficients between each component cause transverse cyclic relative slippage and back-off loosening of bolts. In the previous papers we expressed that the loosening behavior of these bolted joints under transverse loading can be estimated taking into account the relative slippage on the contact interface between the bolt head and the jointed body. The amount of this relative slippage can be calculated using the mismatch of the thermal expansion between both jointed bodies and the bending elastic deformation of the bolts. In the calculations of the bending elastic deformations of the bolts the estimation of the bending compliance on the bolt head contact areas are indispensable. So, in this paper we calculate this bending compliance on the bolt head contact area using finite element method considering contact conditions. Using these results we can derive a simple estimation expressions for bending compliance on bolt head contact areas. By using this estimation method of bending compliance on bolt head contact areas we can estimate the critical relative slippage for any bolted joint structures.

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The elucidation of the cause of the segregation which arises in barrel finishing is desired. This study concerns the behavior of two groups of objects in a rotary barrel, which modeled this phenomenon. Segregation in a two-dimensional system consisting of two groups of objects of differing mass and size was examined by experiment and simulation using DEM (Discrete Element Method). The results of experiment and simulation by DEM showed good coincidence, and it was proven that the induction of the segregation was governed by the combination of the mass ratio and outer diameter ratio of the two kinds of objects. The rotary barrel with eccentricity was also examined.

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A regular and reversible rotation type gas-lubricated conical grooved bearing is developed in this paper. Bearing characteristics of present new type conical bearing are analyzed by the narrow groove theory. As a result, it is clarified that the present new type conical bearing generates the axial and radial characteristics at both regular and reverse rotations and radial bearing characteristics are almost a half of conventional one directional type conical grooved bearings. The bearing parameters which maximize each bearing characteristic (the axial load capacity, the radial load capacity and the stability limit mass) are decided. The bearing parameters which improve both radial and axial characteristics at both rotations were decided.

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Fundamental properties of laser lap welding of thermoplastic materials are studied. It is found that shearing strength of the welded portion increases with the laser fluence but it abruptly decreases by the instability of the welding surface and the formation of a bubble followed by the splash of vaporized plastics. When an absorbent, such as aluminum powder and/or a thin stainless-steel wire, is inserted between two transparent thermoplastic plates, these plates can be welded with combining the absorbent. This is a new laser lap welding for transparent thermoplastic plates, and it can wrap an inorganic material in the welded portion.

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Relations between the energy flux and the irradiation time at upper and lower limits of laser lap welding of thermoplastic plates are studied theoretically and experimentally. From the dimensional analysis, it came out that the energy flux of the laser is proportional to the heat capacity, the temperature increase, 0.5 power of the thermal diffusivity and -0.5 power of the irradiation time of the laser. From the experimental analysis using PMMA plates of 3 mm in thickness, it is found that the energy flux of the laser at the limits is well correlated with the irradiation time of the laser to the power of -0.7.

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This paper describes cylindrical surface finishing characteristics and mechanisms by use of a vibration-assisted magnetic abrasive finishing process. Most previous studies have explored only characteristics of the process. However, finishing mechanisms and the effects of vibration on finishing characteristics are not well known. In this study, a kind of vibration-assisted magnetic abrasive finishing process using mixed type magnetic abrasives (pins and magnetic abrasives) was carried out to confirm the effect of vibration. Moreover, as a basic experiment, a conventional vibration-assisted finishing process using finishing paper was developed in order to clarify the finishing mechanisms in the vibration-assisted magnetic abrasive finishing process. On the basis of these experiments, the finishing characteristics are represented summarily and the mechanisms on vibration-assisted finishing are discussed. Owing to the formation of cross-cutting tracks, the vibration-assisted magnetic abrasives finishing process increased stock removal and reduced surface roughness. In especial, it was shown that the increase in stock removal is mainly due to an increase in stock removal per unit working distance.

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Seeds of developing a new type of material processing using a microbiogenic function are searched with a microbial corrosion test of metals under the seawater. The behavior of microorganisms on corrosion of metals (mild steel, copper and aluminum sheets) is examined, and their action on these metals is discussed. As a result, three processing methods (biomachining, biodeposition and biorecycle) are proposed and discussed.

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With the increasing demands for higher accuracy and higher productivity, high speed ultra-precision table positioning technology is urgently required. In order to realize nanometer positioning accuracy and high speed feed drive, it is effective to minimize error factors in the table system by using a linear motor of a noncontact type. In such a linear motor-driven table system of a noncontact type, however, force ripple of the linear motor deteriorates directly tracking accuracy of the table. In this paper, therefore, we proposed a hybrid linear driving system constructed from a voice coil motor and a coarse driving mechanism, e.g., a wire drive mechanism. Furthermore, we actually developed a hybrid linear motor-driven aerostatic table system, and clarified availabilities of the proposed driving system for ultraprecision table systems.

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Effects of the elimination of water-based cutting fluids on surface finish, chip disposability, tool life and production cost are investigated when a plain medium carbon steel is turned with a coated carbide tool up to a cutting speed of 400 m/min. Wet finish machining can be replaced by dry without any deterioration of machining characteristics: a cutting speed of about 350 m/min, a feed of 0.25 mm/rev and a depth of cut of 0.5 mm are recommended. Although the elimination of a cutting fluid shortens the life of the carbide tool in dry rough machining, the production cost with the optimum cutting speed is little higher than that in wet machining. Finite element machining simulation shows that the temperature in the tool-chip contact area is not substantially affected by a cutting fluid when the heat transfer coefficient varies from 1 to 30 000 Wm^-2K^-1. It is recommended that the use of a high-thermal-conductivity tool such as cBN produces a better cooling effect than the application of cutting fluid with respect to reducing the tool-chip contact temperature.

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This paper deals with the elimination of water-based cutting fluid based on machinability tests and economical considerations when plain medium carbon steels and an alloy steel are machined with a coated carbide end mill or a carbide drill. In end milling, no remarkable difference between dry and wet machining is recognized in terms of chip disposability, machining accuracy, cutting force, tool life and production cost. Besides, dry machining yields a low production cost at low cutting speeds of less than 90 m/min for S 45 C steel and 20 m/min for SKD 61. In drilling, dry machining is not as good as wet machining with respect to machinability, but the cost analysis shows that dry machining is preferable at low cutting feeds of less than 200 mm/min for S 50 C steel. From an environmental point of view we should take a positive attitude to introduce dry machining as far as its advantages on machinability and economics are recognized.

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This paper aims at developing a new simulation system for evaluating performances of a material handing system which we call the permutational circulative vehicle routing system (denoted PCVRS). The PCVRS consists of multiple vehicles, multiple stages and a rail of single loop type. The vehicles unidirectionally circulate without passing on the loop and process jobs including loading and/or unloading at stages placed along the loop. The simulation system developed is based on a series of equations describing event's schedules. As a case study it is applied to an input/output system in an AS/RS (automated storage and retrieval system), and its behavior is analyzed from both empirical and theoretical points of view.

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Virtual enterprise is a temporary alliance of enterprises that come together to share skills, core competencies or resources. Each enterprise forming a virtual enterprise has to select appropriate business partners to realize profitable management with eliminating the risk. In this paper, the negotiation process in virtual enterprise formulation is focused as a basic study to clarify its effective management. We develop a computer simulation model to form a virtual enterprise through multiple negotiations amongst several potential members in the negotiation domain, and clarify the negotiation dynamism in the virtual enterprise formation.

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In this paper, a method of evaluating the production control efficiency level of the plant is proposed. Evaluating system for the production control had been developed as the Diagnosis Model of the Production Control Efficiency Level of the Plant which contains eight functional key indicators. The synthetic results of the plant are figured by utilizing the theory and methodology of Data Envelopment Analysis. Efficiency of the plant, result of improvement activities as well as the ranking of eight plants in six countries is presented.

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The Japanese regulatory system causes problems at the working level due to the discrepancy between the regulatory framework and the actual regulatory operations. Accordingly, regulatory reform and innovation of administrative law are desired. The theory of regulatory reform, utilizing the techniques of combination of Independent Agencies and Standards, which was recommended in 1972 by Robense Committee for the regulatory reform in the fields of UK's Health and Safety at Work, is studied in the light of both the America's philosophy on Independent Agencies and the strategy of European Communities for its economic integration.

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