To clarify suitable oscillating characteristics of Nd:YAG laser for removal of biological bone, the experimental study was carried out. Femurs of cattle were used as specimen, and then they were drilled with three different YAG-laser oscillators. Around the holes drilled with the lasers, the white and black layers, which are seems the thermal affected layers, were generated. Volume of material removed increases with irradiated energy of laser. However the removal efficiency decreases for the low peak-power laser because the storage of heat in the specimens required making up for energy shortage. In case of the laser with low peak-power and long pulse duration, the irradiation causes increase of storage heat, and then makes the thermal affected layer thick. From these results, to remove biological bone with Nd:YAG laser in free of damage, it is found that the laser has to oscillate with high peak-power and short pulse duration.

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This study deals with rising behavior of solidified oil particles in liquids. We measured rising velocity and drag coefficient of the particles. The measured rising velocity was compared with calculated ones. The results are summarized in the followings: (1) The measured rising velocity agreed well with the calculated ones. (2) The drag coefficient of hexadecane particle is higher than those of rigid spheres. (3) The discrepancy of the drag coefficient between hexadecane particle and rigid sphere seems to be attributed to their surface conditions.

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Onset of the oscillatory thermocapillary flow in a half-zone liquid bridge is investigated experimentally taking into account effect of ambient fluid motion. A number of studies have been carried out on the critical condition of the flow transition, but few researches considering ambient fluid have been reported. In the present study, the liquid bridge and the ambient gas were confined in a temperature-controled closed vessel. The flows in the bridge and the ambient gas were visualized by suspending tracer particles in both fluids. Simultaneous observation of both fluid motions from the top has been made first in this work. Boundary condition of the ambient fluid was varied by two partition disks placed horisontelly to the liquid bridge. Visualized fluid motions and corresponding critical conditions are discussed.

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The onset of oscillatory thermocapillary convection in a half-zone liquid bridge is known to be sensitive to heat transfer at free surface of the liquid bridge and ambient air motion. Its mechanism and three-dimensional nature of the oscillatory flow, however, is not yet fully understood. In the present study, these effects on the onset of oscillation are focused. Three-dimensional simulation of both thermocapillary convection in the liquid bridge and the ambient air motion is performed for an intermediate-Prandtl-number fluid by the finite difference method in order to determine the onset of oscillation. The effects of the viscosity of the ambient air as well as heat loss through the free surface are discussed.

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This study examined the germination situation from the species of rice plant, growth of the seedling and decreasing of putrefactive bacteria adhered to the black sesame by the low-temperature plasma irradiation. A 10 minute irradiation of the low-temperature plasma to species of the rice plant is the most effective for the rearing after the germination from the species.

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This paper is a basic research for effectively utilizing incinerator ash and waste tire, etc.. In mixing them with the asphalt, the utilization as a road surface material for the snowmelt is considered. Apparent thermal conductivity and transient temperature response characteristic of the mixture were examined in order to grasp thermal characteristics of the mixing road surface material. It is required that thermal conductivity and time constant of the material are big as a snowmelt road surface. It was proven that methods for mixing bottom ash with the asphalt were effective measures as a heat transfer characteristic.

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In this study, the change of water temperature in the process, which unsteadily decompressed the liquid of room temperature from the atmospheric pressure, was measured. In addition, generation behavior of the bubble in the boiling and generating process of the ice were observed by the high-speed video camera. This study is basic research with the aim of the application to efficient ice making which contains large number of minute bubbles. The inclusion mechanism of the minute bubble to the ice was clarified from the viewpoint of the heat transfer engineering.

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The onset of nucleate boiling, the point of net vapor generation and critical heat flux on subcooled flow boiling, under oscillatoryflow focusing on liquid velocity, amplitude and frequency of oscilations were investigated experimentally and analytically. Experiments were conducted using a copper thin-film and subcooled water in a range of the liquid velocity from 0.27 to 4.07 m/s at 0.10MPa. The liquid subcooling was 20K. Frequency of oscillatory flow was 2 and 4 Hz, refpecpively; Amplitude of oscillatory flow was 25 and 50% in a ratio of main flow rate refpecpively. Temperatures at the Onset of Nucleate Boiling and Critical Heat Flux obtained in the experiments decrease with the oscillatory flow. The decrease of liquid velocity by oscillatory caused ONB and CHF to decrease.

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Subcooled flow boiling of water is performed in a horizontal circular channel with different diameters of 5mm, 10mm and 16mm. Microbubble emission boiling (MEB) occurs in transition boiling at above 20K of liquid subcooling and the heat flux increases higher than the ordinary critical heat flux. The liquid velocity gives strong effect on the heat flux increase in MEB. The maximum heat flux reaches 10 MW/m2 at 30K of liquid subcooling and 2.5m/s of liquid velocity. Periodic pressure fluctuations in the channels are observed in many cases of MEB. In the periodic MEB, heat fluxes increase in proportion to the frequency of the pressure fluctuations regardless of channel size, liquid subcooling and liquid velocity.

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Subcooled flow boiling of water is performed in a horizontal small rectangular channel with 5mm height and 14mm width for the purpose of high heat flux cooling of power electronics. A small heating surface of 10mm length or 20mm length for 10mm width is located on the bottom surface of the channel. Microbubble Emission Boiling, MEB, occurs in transition boiling and higher heat fluxes than 500W/cm^2 are obtained. For the longer heating surface, the heat flux in MEB decreases for the down stream of the heating surface because of falling the subcooling of liquid. At lower liquid subcooling of 20K and lower liquid velocity of 0.3m/s, unstable MEB is observed to transit easily to film boiling. The experimental results suggest how to keep the subcooling of liquid at least 20K for the down stream section of electronic devices.

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We develop a new vehicle to improve human mobility. It is modeled on the magic broom, and is named SWEEPWE. SWEEPER is lightweight and smart size, so it has high portability. SWEEPER is deigned in consideration of multipurpose use, for example, a substance of bicycle, avehicle for entertaiment. In this paper, we descride design concepts of SWEEPER, deveropment of a prototype, the questionnaire evaluation by trial ride and future works based on the evaluation.

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Wearable robots, especially power suits to enhance human activity are one of most interesting topics. This study aims to develop a power suit installing a variable stiffness mechanism. In a previous study, we showed the relation between impedance parameters of power suits and human performance, and verified the effectiveness of self impedance matching method using soft computings. In this paper, we conduct fundamental experiments in order to design a variable stiffness mechanism which can tune the stiffness of joint mechanically. Experimental results show the effectiveness of variable stiffness for improving human performance and reducting muscle fatigue.

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We propose the open development system that can be applied to the mechatronics educational material. This system shows the information about mechatronics educational material on the Internet for feed-back. For this purpose, we developed mechatronics material that was used for building a line-tracing robot. In this paper, we described the result of applying "Developed Educational Materials" to "Electrical Engineering Class of Shibaura Institute of Technology." And we described the Web application for handling material information in this system.

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This paper provides the walking robot system using HMD (Head Mount Display) and Joystick. The operator can control the walking robot as if he get on it. We developed the three walking patterns in full consideration of the stability.

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We are researching a new base technology which it can make use of for a robot in the daily environment .from the viewpoint of handling domestic articles. This report shows how to teach a robot for grasping a towel through the monitor screen as a part of a new framework. A towel is one of typical soft limp materials which are flexible and rather difficult to find grasping point automatically. So an indication for towel handling is considered here in order to teach a grasping point to a robot with a two fingers gripper.

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The dynamic characteristics of journal bearing lubricated with ferrofluid are investigated using the two-dimensional lubrication equation for finite journal bearing lubricated with ferrofluid. The stiffness coefficients and damping coefficients of the journal bearing are derived. The influences of the magnetic force, the angular moment of particles in ferrofluid on stiffness coefficients and damping coefficients are discussed. The results manifest that both the magnetic force and the angular moment of particles in ferrofluid affect the coefficients, and the smaller the eccentricity ratio of bearing is, or the lower the rotation speed of the shaft is, the larger the influences are.

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Sealed rolling bearings are widely used in many applications such as automobiles, some electric motors and industrial machinery because of their easy handling. In this study, bearings equipped with different types of seals are operated in muddy water with the inner ring rotating, then their performance is evaluate quantitatively by three distinct methods: measuring their weight change, noise and vibration, respectively. The results show that the method of measuring vibration using an anderon meter is superior to the others.

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In this study, investigation was made on the traction characteristic under wide-ranging mean Hertzian pressure from 0.7GPa to 2.3GPa with using various axial direction curvature steel specimens. And then, same tests were carried out under test conditions for several types of traction oil. As a result, in the case of the synthetic naphthenic traction, oil, it was shown that the maximum traction coefficient increased slowly with the increase of mean Hertzian pressure at the first stage of that traction coefficient curve. After then, that traction coefficient curve gradually decreased. And, the numerical analysis was carried out by the Tevaarwerk's elastoplasticity shearing model with some oil film properties in EHL state reported by another researches.

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The loading cam for traction drive system is made by V-cam and ball system. But this loading cam becomes very hard Hertzean stress by the point contact. So loading cam is developed by MOTRON・DRIVE can be lower than former loading cam at Hertxean stress, before a slope safece of V-cam is able to retation with roller for a varied load.

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The CVT of 3K type planetary gear system was developed by MOTRON・DRIVE for electric vehicle. This CVT is used a traction drive system and has wide speed ratio from 0 to 1:1, and can be small sized and lightweight. In this report, A speed ratio of the CVT is designed from 0 to forward and reverse, besides a speed control of the CVT is able to mechanical system combined with accelerator pedal. The speed control system is made a component of shift element of CVT, V-cam element, cam-follower and sensor.

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Traction characteristics of polymer solutions were determined at a constant rolling speed of 0.05m/s over a range of temperature with a disk on ball type EHL tester using steel disk. As the temperature is raised, the traction curves of base oil as well as conventional polymethacrylate containing oil increase, while those of dispersant type polymethacrylate containing oil remains constant. Such a tendency was more significant for hydro cracked oils than solvent refined oils. The measured oil film of dispersant type polymethacrylate containing oil showed much thicker than polymethacrylate containing oil. It was inferred that dispersant group of DPMA contributed to the friction reduction due to thick film formation in EHL contact.

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A pin-on-disk tribometer was constructed as a trial machine, with which an endeavor was made to obtain the wear rate in step load method throughout the run. Experiments were conducted for aluminum alloy and cast iron using some lubricants, in which the friction coefficient, the contact potential and the wear length were determined. By making the correction of the wear length based on thermal expansion and elastic deformation of test specimen, it was found that the measurements of wear rate on the tribometer had a sufficiently accurate data.

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Friction and wear properties were evaluated for some synthetic lubricants including polyalkylene glycols, polyolester, perfluoropolyether and polyalphaolefin with an aluminum alloy pin on cast iron disk type tribometer in HFC-134a refrigerant environment, in which the friction behavior and contact potential, were also determined. The anti-wear performance revealed the boundary lubricating effect of the lubricant tested in refrigerant environment. That is, comparing among the lubricants, the wear resistance was the best for perfluoropolyether fowled by polyolester. On the contrary, polyalphaolefin showed the worst friction and anti-wear performance.

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Tribological properties of rapeseed oil, polyolesters and hydrocarbon oils were studied for an Al alloy and Al alloy and a combination of Al alloy and cast iron with a pin-on-disk type tribometer. For a combination of Al alloy and cast iron, rapeseed oil showed the lowest friction coefficient throughout the run, and the highest anti-wear properties among the oils tested, meanwhile it showed the worst tribological performance for Al alloy and Al alloy. This is probably due to chemical wear followed by abrasive wear based on formation of excessive aluminum soap on the sliding surface.

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Ti-based composites containing fine diamond powder were fabricated using spark plasma sintering. 'We evaluated their friction and wear properties with a reciprocating friction tester in water and air using an Al_2O_3 mating ball. The addition of diamond to the matrix considerably decreased the composite's friction in water as well as ambient air. The specific wear rate of composites was negligible in water and air, although a little wear of the mating ball was existed.

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Light emitting diode (LED) will be new light source for automotive forward lighting system in the near future. One of the fundamental technologies as to control LED is how to manage the maximum junction temperature on a tip under the phosphor. Whereas, heat sink is used as a basic and reasonable device for thermal diffusing, effects of heat sink's shape and dimension are not specified for LED application. In this paper, temperatures of three different heat sinks were calculated by CFD tool using with three dimensional model including LED, heat sink and air. The junction temperatures obtained from calculation were compared with estimated junction temperatures based on measured temperature under the bottom of the LED, because of difficulty to measure the junction temperature directly. The results of our study indicates that junction temperature is predictable using CFD.

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A new convection in micro-gravity was discovered that occurs when droplet burns off a node and an anti-node of standing sound waves experimentally. The convection is named "thermo-acoustic streaming". It has found that the thermo-acoustic streaming promotes a burning rate. The situations around the streaming are not investigated yet. Detailed distribution of velocity, temperature and density, particularly time resolved flow field, is difficult to know in experiments. If the numerical experiments are possible on the thermo-acoustic streaming, detailed data can be obtained easily. The numerical model has been created anew. We succeeded in reproducing the thermo-acoustic streaming by numerical simulation. The changes in the pressure distribution and the velocity distribution are the cause to generate the thermo-acoustic streaming. We have clarified the mechanism of the streaming and obtained detailed data beyond experimental restriction.

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Lateral oscillation of a wire electrode occurs when high dc voltage is applied between wire and plate electrodes with corona discharge. The main purpose of this paper is to investigate the influence of heating current on the wire oscillation experimentally. In this experiment, only heating current is changed to satisfy the purpose. First of all, the wire oscillation is examined and then, the fluid field is measured. As a result, it is confirmed experimentally that the current heating does not affect the mechanism of the wire oscillation.

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Lateral oscillation of a wire electrode occurs when high dc voltage is applied between wire and plate electrodes with corona discharge, and also the string that is stretched in parallel to the wire electrode. The fluid force on the wire due to corona wind was assumed to be one of main reasons for the outbreak mechanism of the oscillation. To clarify the relationship between the fluid force and the outbreak mechanism of the wire oscillation, the flow field must be confirmed. In this paper, the velocity field is measured with the PIV technique.

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Dynamic damper has been used in order to reduce the shakes in case of the wind, a small-scale earthquake, and so on. However, there is a possibility that the dynamic damper damages apparatus around it because it vibrates greatly on large earthquake. This study is researching new structure of dynamic damper from large to small vibration. The structure is as follows. Impact Wall is fixed conventional space from mass of dynamic damper. When the mass vibrates more than the space, it collides with the wall. By this collision, the higher stable modes are excited at object, and vibration energy is carried away faster. As a result, response of displacement on object is made smaller. And damage of apparatus around dynamic damper is not done because vibration of dynamic damper is limited by wall.

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This paper describes the experimental results and analytical ones on synchronized phenomena of weakly coupled oscillators by magnetic force. Two permanent magnets are attached to the arms of pendulum of the system. The pendulum is driven by electromagnetic force. When four oscillators are arranged in same line, in-phase synchronization, out-of-phase synchronization, and nonsynchronization are observed under some operational conditions.

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In a current railway system, there is a problem that pantographs are sometimes detached from catenary. The faster the train becomes, the more problematic it would be. We investigate experimentally and discuss the problem using the simple model, of which the motion takes place in a mechanical similar manner with the real pantograph.

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In this paper, the effect of vibration suppression of a dynamic vibration absorber using a three-layered cantilever beam to a clamped-clamped beam is discussed theoretically, numerically and experimentally. The three-layered beam consists of two copper plates and viscoelastic material, and has the shape of a uniform strength beam.

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In the automatic weighing of packages in motion, the sequence of products is generally completely random. Long, short, heavy and light products are passed over the conveyor belt scale in any kind of random sequence. Through the multi-stage conveyor belt scale, a weighing scale can be created which will adjust the conveyor belt length to the product length. Our interest is directed to solve many technical problems when we put the multi-stage conveyor into practical use. Consequently, our weighing algorithm proposed here will give us an accurate and desirable performance with the possible improvements.

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The fatigue strength of cyclic hardening materials under constant mean stress condition increase when the maximum stress becomes larger than the yield stress and cannot be estimated accurately based on the fatigue limit / strength estimation method proposed previously (e.g. Modified Goodman's curve). In this paper, the fatigue tests of SUS316NG and SM400 steels as cyclic hardening materials are carried out under constant mean stress condition and the relationships between fatigue strength and failure life are obtained. From the test results, it is shown that the difference between modified Goodman's estimation and fatigue test result changes linearly with the increase of maximum stress. Then, the approximate equation for the relationship between the difference and maximum stress is derived. By using the approximate equation for evaluating the difference and the results of modified Goodman's estimation, it is shown that the fatigue strength of cyclic hardening material under constant mean stress condition can be estimated with practically sufficient accuracy.

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Welding is widely used for many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades fatigue strength. Some methods for reduction of residual stress are developed. Residual stress is also generated when wheel is welded. In this paper, a new method for reduction of residual stress using vibration is proposed. As vibration, ultrasonic vibration is used. An improved device for transmission of vibration is used. By using the proposed method, tensile residual stress is reduced.

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Welding is widely used for construction of many structures. Residual stress is generated because of locally given heat. Tensile residual stress on the surface degrades fatigue strength. In this paper, a method for reduction of residual stress using ultrasonic vibration during welding is proposed Effectiveness of the proposed method is examined experimentally. Especially, duration of vibration is focused on. It is found that tensile residual stress near the bead is significantly reduced when ultrasonic vibration is used.

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Securing of the safety against the disaster which it suffers the speed-up of the machine and impact is requested. Some structure absorbs movement energy by thing to break pressure efficiently, and safety is secured in the impact design. Because it changes by the form of the composition member and the materiality, impact absorption performance must control the amount of energy absorption due to the deformation of the structure. In this report, it was examined about impact absorption performance to receive a impact load about the load direction and the buckling deformation experimentally.

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In general, polymer is it is a deteriorated material. The research on the degradation has been done from various viewpoints between the past and present. However, the influence by the degradation of the dynamics load had been hardly done. Then, the influence on the tensile behavior by the dynamics load was examined by using the polycarbonate for the test specimen in this research. As a result, It is cut into a low molecule by the tensile load. It was confirmed that the yield stress depended on intertwining the molecular chain by the influence, and the rupture stress depended on the molecular weight in addition. As a result, influencing the mechanical property became clear. Moreover, cutting the molecular chain is repeated by the cyclic loading over the whole as for the test specimen. The intertwining point decreases because of the influence. In addition, the material strength's decreasing by the cyclic loading's joining in the crack tip neighborhood became clear.

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Surfactant molecules form a monolayer on the water or a bilayer in the water. These membranes fluctuate. It is also well known that an ordinary crystalline model of membranes undergoes a second order phase transition. We numerically study the phase transition of a model of crystalline membranes by using a new definition of the bending energy.

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To make composite materials composed by biomass and biodegradable plastics, the wettability between sugi wood and biodegradable plastics have been studied, which are useful in enviromental view. The wettability between sugi wood and biodegradable plastics were increased with increasing heating temperature. Moreover, breaking stress were increased with increasing temperature up to 170℃, and decreased from 170℃ because the coupling strength of the lignin of Sugi may fall at that temperature. It is necessary to combine sugi wood and biodegradable plastics at lower than 170℃.

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The Al-Si particle dispersed compound materials have been made from pure aluminum particle and silicon particle by non-dissolution method, and the hardness and wear resistance were examined. The wear resistance and the hardness of the materials become large by the amount of volume fraction, and by the particle size of silicon in the material. It has been understood that this result came for the material to became hard by changing volume fraction and particle size of silicon.

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The effect of surface treatment by Ni electrodepositon and the following diffusion treatment on the ductility of cast iron was investigated. The fracture stress and strain of Ni coated specimen was higher than those of as-coated specimen. The fracture stress and strain was increased with increasing Ni diffusion treatment time. The improvement of fracture stress and strain in the Ni diffused specimen was discussed by analysis of fracture surface.

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From a practical point of view, the numerical simulations of structure and flow fields are indispensable in the fields of engineering. In order to calculate the structure and flow fields, we apply to a coupling technique with the Arbitrary Lagrangian-Eulerian (ALE) method. As an example of the moving boundary flow problems, we apply to calculate around a 3-dimensional elliptical body. The numerical results are compared with the flow fields around a Stillness body.

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Surfactant molecules form bilayer lipid membranes (BLM) in water. The surface of BLM fluctuates. The shape fluctuation transition of a model of BLM without fluidity is known to be of second order. We study the fluctuation phenomena of the model with fluidity by Monte Carlo simulations with dynamical triangulation. We find that the transition of the model is influenced by the dynamical triangulation.

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Electronic packages such as BGA packages have both micro and macro structures, and it is difficult to construct simulation models for such multi-scale structures. Therefore, multi-level modeling methods suchi as global and local submodel method are needed to establish constructing the simulation models. However, the accuracy of such multi-level modeling methods are not clear. Therefore, authors verified the accuracy of the multi-level modeling methods for BGA packages.

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