An aseismic system using vibration isolation rubbers is proposed to reduce seismic responses and vibrations of diesel generators (DG). About 20Hz is considered as natural frequency of the DG supported by the aseismic system. This paper presents an experimental study for evaluating vibration isolation performances of the vibration isolation rubbers in high frequency range. Vibration tests using test model composed of steel weights and 2 isolation rubbers are performed. Effects of compression stresses and response deformations of the vibration isolation rubber on acceleration transfer functions and damping ratio of the test model and dynamical spring constants of the vibration isolation rubber are evaluated.

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Rubber vibration isolators (R.V.I) are widely used as vibration isolating member. In this paper, optimal vibration control of vertical vibration body using dynamic absorber consist of a mass and a rubber element are analyzed theoretically and confirmed experiments. The spring elements for both the primary system and the secondary vibration system of equivalent models with two-degree-of-freedom vibration isolator system are assumed to be rubber elements which have complex spring constant. When the primary system has a loss factor, the optimal values are derived by a mass ratio variation method using the numerical calculation. Vibration reduction effects (vibration transmissibilities) are measured experimentally. The results show good agreement with calculated ones. It is concluded that the complex spring model can be explained well for optimal vibration control with vertical vibration isolator system

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In this report, the authors have developed a nonlinear spring mechanism for a vertical seismic isolation device. The nonlinear spring mechanism consists of torsion springs and V-shape link mechanisms. The frequency and seismic responses of a vertical seismic isolation system using the nonlinear spring mechanism were measured using a shaking table. The experimental results were compared with the calculated results, and the effect of vibration suppression of the isolation device and the propriety of the calculations were substantiated.

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This paper describes experimental and analytical results of friction induced vibrations of a flexible vertical shaft. The rotating shaft is supported with rubber support at an intermediate position. In this study, backward whirling motion of the shaft is observed. From frequencies analysis, dominant frequencies of the observed vibrations are natural frequencies of the shaft. The vibrations occur only in the range natural frequency increases, as the span of support increases. The analytical results are good agreement with experimental one's.

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The sensitivity of a fishing rod is related to transmitting behavior to an angler when the a fish to rise to the bait and the motions of the lure. In this study, the sensitivity of a fishing rod is clarified. The transfer function and the behavior of a fishing rod were measured in the rockfish fishing. Based on the experimental results, the sensitivity of a fishing rod was discussed and it seems reasonable to conclude: (1) When the fish to rise to the bait, two kinds of the behavior of fishing rods are observed. (2) The vibration characteristics are different in the structures of the tip of a fishing rod. (3) The sensitivity of a fishing rod is evaluated from the damping ratio and the transfer function.

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This paper describes a research of vibration characteristic in vacuum pump. The vacuum pump is used for manufacturing the semiconductor etc. When the vacuum pump stops, it influences the entire production line. Therefore, it is requested from the vacuum pump not to break down while operating The rigid motion and the bend vibration that increases the vibration at the same time as understanding the operating vibration characteristic are understood in this research. Moreover, the model to be able to confirm the problem in operation etc. When the operation condition and the design condition are changed is made. The model making makes from the vibration characteristic of an actual vacuum pump, and understands the change in the vibration characteristic by the change in the design condition at the same time.

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The method of conventional experimental modal analysis in our laboratory is difficult to measure the vibrational characteristic of rotary structure which was under operation. So, the final purpose is to investigate the vibrational characteristic which was under operation. For that, we analyzed the experimental mode by using strain gauge, because the acceleration pickup that had been used so far wasn't able to be used which was under operation. And, we investigated the vibrational characteristic by using the acceleration pickup and the calculation by computer before operating experiment Then, we compared each other and examined the correspondence of the result used strain gauge. And we calculated strain modal shape under operating.

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This paper studies how to calculate an analysis solution for the forced vibration problem of the undamped multi-degree-of-freedom system using two parameters, a mass ratio and a spring constant ratio. The technique expanded to N degree of freedom especially on the basis of three degree of freedom is proposed. It was shown clearly that the anti-resonnance point of degree of freedom is certainly in agreement withe the resonance point N-1 degree-of-freedom system from the vibration transmissibility and the amplification factor curve of a primary vibration system obtained by the formula manipulation sowtware "Mathematica (Ver. 5.1)".

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In this paper paying attention to the automobile seat and riding person, technique of acoustic analysis on acoustic material is examined based on the hybrid method of the experiment and the analysis. These are concretely analyzed by setting acoustic impedance to the boundary condition. Finally, sound field of semi-anechoic room assumed as automobile interior can be designed by development of acoustic model for automobile interior in consideration of automobile sea and riding

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The purpose of this sturdy is to improve the further comfort and to save the energy by controlling the task region of the task/ambient conditioning system automatically. So the controller which controls the temperature of an individual task region is derived in the situation in which the task region influences each other in this paper. First, the experimental apparatus was constructed and it modeled by the neural net. The controller which was able to be controlled of the desired was derived by building it into GA and using the proposed chromosome structure.

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We investigate the possibility of quenching self-excited sound generated by two Helmholtz resonators. To quench using another sound as interference, the frequency of the two sounds must be identical and their phases opposite. Two resonators are connected with tube at the bottom of the resonator in order to synchronization. We found that the phase of self-excited sounds depends on the length of the tube that is connecting two resonators.

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First, The correlation of the subjective evaluation and sound metrics is taken into account for shutter sound. And the target that considers person's sensibility is decided. Next, kinematic analysis is performed. The data obtained in kinematic analysis is brought to acoustic analysis, and sound is created. Finally, the sound made from acoustic analysis is evaluated, and design on comfortable sound is achieved.

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In this paper, we propose an entirely new method which achieves higher speed of operation and highly accurate length measurement of products on a conveyor belt. Our goal is to measure easily the length of a product with a digital image taken by a digital camera. This paper describes an estimation method of the length of the product in case of the change in slanting angle to the conveyor.

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A small active seat suspension has been designed and manufactured for a one-seat electric vehicle. Our aim was to develop a vibration-isolation system for the driver's seat suspension using active control. However, the evaluation of ride comfort while the electric vehicle was running has depended on subjective judgement by drivers. Thus, it is necessary to evaluate the correlation of subjective judgement with objective judgement based on physical values, i.e., vibrations. In this study, we performed a sensory evaluation of riding comfort. In addition, the factors affecting the sensory evaluation value were examined by questionnaire investigation. As a result, we confirmed that the aggression and the private space function were correlations for the quality of riding comfort.

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FRP (Fiber Reinforced plastic) is widely used for construction of many structures because of its high strength to weight and stiffness to weight. A structure is made of a new developed FRP. Structure is subjected to static load and dynamic load. Thus, response of structure made of FRP subjected to dynamic load is one of important items considered in design. In this paper, dynamic characteristics of structure made of FRP are measured. The damping ratio and the natural frequency of structure for some manufacturing conditions are measured.

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Recent years, automatic transmission in car is prevailed excellent for safety, and comfort. Planetary gear with complicate behavior is used in gear mechanism and may cause a noise at specific frequency. It is very difficult to measure the vibration directly because of narrow space however it is desired to measure the vibration indirectly to understand the behavior of the Planetary gear. This paper describes the technique for prediction on vibration behavior of Planetary gear that cannot be measured the directly.

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Seismic response of structures is nonstationary random process. Mean square value is one of representative values representing statistical characteristics. In this paper, a simplified estimation method for the integral of mean square value of the response is proposed using mean square value of stationary random process.

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When the system is subjected to excess dynamic load, the response has hysteresis loop characteristic caused by plastic deformation. A practical estimation method of the first excursion probability of such structures subjected to random excitations such as seismic motions is proposed. The first excursion probability of structures with hysteresis loop characteristic is obtained from theoretical method. When the tolerance level is normalized by the expected value of the maximum response of the structure with hysteresis loop characteristic, the first excursion probability can be estimated independent of the damping ratio and the natural period.

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The flow around a circular cylinder, which is placed near a rigid plane boundary, with tangential blowing is investigated experimentally under the condition of Re=2.7×10^4. The time-mean surface pressure measurements and flow visualizations were carried out for various momentum coefficient C_μ, slot locations θ_J and clearances between the circular cylinder and the rigid plane boundary, H/D. The results of experiment show that the reverse flow occurs in the gap at certain C_μ. The value of C_μ for the occurrence of reverse flow in the gap depends on θ_J and H/D. In addition, the characteristics of the lift forces can be represented by a newly defined nominal jet momentum coefficient C_μ' and nominal lift coefficient C_<I.>' for 30°≦θ_J≦110°.

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Unsteady fluid forces acting on a discoid airfoil model in the sinusoidal pitching motions under conditions of several frequencies were measured by using the ring structure 2 elements balance. Furthermore, the vorticity field near the trailing edge of the model was also measured by using an X-type hot wire probe. Dynamic lift/drag coefficients were compared to the steady ones. It is confirmed that the pitching motion is available for keeping lift higher after the separation occurs. The delay of stall for the pitching model is observed and also the value of maximum lift coefficient is greater than the maximum lift coefficient under stationary condition. The dynamic lift acting on a pitching model is strongly influenced by vortices shed from the outer edge of the disk.

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Unsteady fluid forces acting on a three dimensional model in the sinusoidal pitching motions under conditions of several frequencies were measured by using the ring structure 2 elements balance. Dynamic lift/drag coefficients were compared to the steady ones. In this study, in order to investigate the effect of leading edge profile on unsteady fluid forces, two types of model were installed: a discoid airfoil (Model-CN) and a triangular wing-shape (Model-TR). The delay of stall for Model-CN is observed and also the value of maximum lift coefficient is greater than the maximum lift coefficient under stationary condition. On the other hand, dynamic lift/drag coefficient profiles for Model-TR show same tendency to the dynamic lift/drag coefficient profiles under stationary condition. The unsteady fluid forces are affected by the leading edge profile.

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A materials handling between the production lines plays an important part to realize a cost reduction in the mass production of the product. A product is distributed when that work piece is specially the thin film tare of the rubber which can't hold a form by oneself, or the plastic. That alignment precision and carriage time become the important elements for a line speed. In this report, the transport device of the work by the swirl flow is developed, the mechanism of the work piece carriage by the swirl flow is examined by the performance estimation of the device and a flow visualization.

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In the Japan Atomic Energy Agency (JAEA), a pilot test program has initiated to produce hydrogen at a rate of up to 30Nm^3/hr by using thermo-chemical water splitting method by the iodine and sulfur (IS) process. Chemical reactors of the pilot test plant are necessary to be optimized through analytical design works. JAEA is developing a multi-phase analysis code coupled with chemical reaction to design chemical reactors especially for the Bunsen reaction. The new developing code predicted swirl flow pattern with vortex breakdown shown by flow visualization in a cylindrical vessel with rotating bottom surface.

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The oscillatory responses of a single leaf of sweet potato are examined under lighting by a fluorescent light in a uniform airflow. The leaf displacement is measured using a laser displacement detector, and the power spectrum of the data is calculated. The equilibrium position is changed as a function of time when the light is leaved on for one hour and after tuned off. The primary resonant frequency of the leaf has shifted to higher range, and its magnitude of the power spectrum has increased during the experiments. These dynamic characteristics are due to the deformation of the leaf shape by the phototropism. These responses also suggest the influence of the airflow, because the evaporation from the leaf is activated. Future study is directed to examine the various lighting effects, on plant holophyte.

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The research is aimed to develop a fish robot with swinging fins. Though, there have been many excellent researches on this topic, the fish robots have not enough propelling efficiency comparing with natural fishes. The ultimate goal of this research is to develop fish robot of high efficiency as natural creatures. As the first step of the research, we start with a very primitive one link model. This note shows primitive analysis and basic experiments with a simple prototype.

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A sensing/transporting system that moves along with fluid inside a small-diameter tube is recently studied by many researchers and expected to be developed for engineering applications such as a PIG for a pipeline and a micro machine. Flow field ahead, inside, and behind a rigid body has been experimentally observed and analyzed with a support of a unique numerical program. It was observed that there exists a Rankine compound vortex at the inner-rear part of the body. A flow layer where the flow is trailed along with the moving top surface was also observed. It is concluded that a Rankine compound vortex appears at the inner-rear part of the body. It is also concluded that, as the Reynolds number increases, the layer becomes thin and the flow only moves within the layer.

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The high-speed pulsating flow is found in the exhaust system of the reciprocating internal combustion engine, the piping system connected to reciprocating compressor, etc., and has various features which never exist in the steady flow. This work is concerned with an experimental study of the high-speed pulsating flow in a straight pipe and the jet discharged by the pipe. The pulsation is generated by disk-type rotary valve at upstream end of the pipe, and frequency of pulsation can be varied by changing the rotating speed of the valve. The measurement is performed for different pressure ratios of plenum tank to atmosphere at different speeds of the rotary valve. A new static probe was designed to apply to supersonic unsteady jet, and the static pressure histories were measured. The static pressure distributions in the flow field were compared with the visualized schlieren pictures and discussed

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The purpose of this study elucidates a structure of internal flow in vacuum ejector. The vacuum ejector is used as a part of automatic conveyance systems, in which precision components and food were handled utilizing vacuum pressure produced by the ejector. So far, the vacuum ejector has been designed mostly by experience and the internal flow in vacuum ejector is not well analyzed. The flow field of ejector is so small that conventional measurements can not be employed and it is difficult to obtain the detailed information. Thus, the flow in the ejector is simulated on water table using hydraulic analogy. In this paper, to obtain optimum performance of the ejector, we examined the different ejector models with some parameters, such as the nozzle width and the nozzle-mixing chamber space. The vacuum ejector model, in which nozzle width is 40mm, mixing chamber 100mm in width, nozzle-mixing chamber space 40mm, demonstrates maximum performance.

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The WIG has worse stability of the pitching moment to change of a flight altitude compared with a conventional airplane. In order to solve this problem, aerodynamic characteristic of S-shape wings were examined by carrying out wind tunnel experiment by applying reflected image model method to reproduce the ground. The wing profiles used for the experiment are NACA6409 which has high cambered profile and two different S-shape wings. From the experiment, it is found that the S shape wing is inferior in lift drag ratio, but it is superior in stability of pitching moment compared with the NACA6409.

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The purpose of this research is to make clear a possibility of eco-machining process for turning of carbon steel S45C. Cutting experiment was carried out both dry and wet cutting using carbide tool in cutting speed 150m/min. Observing the process of chip formed, high-speed camera was used. As a result, flank wear and crater wear are not much difference between dry and wet cutting, but boundary wear of dry cutting is about 4 times larger than that of wet cutting. A cause of boundary wear occurred is to cut ruggedness which occurs by intermittently metal flow to free surface in the side of shear type chip. It seems that the reason why an effect of cutting fluid is remarkably shown for boundary wear is that cutting fluid enters easily into interface of tool and work because of cutting in this part done intermittently.

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Corner division of the machining article was newly instituted by JIS as quality and property of the edge, and the machined surface accuracy was regulated. This study is to develop the method for polishing corner R of the inside aluminum square tube in the magnetic support processing. Basic experiment was carried out using tow magnetic particles and tow magnetic abrasives as a preliminary experiment. As a result of the experiment, material surface roughness was able to improve from 0.109μm Ra to 0.082μm Ra. C Type was the best mixing abrasive grain.

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A major source of air pollution is internal combustion engines. Especially, compression ignition engines in today's automobiles contribute the most to particulate emission and soot, and it is recognized that these emissions have a detrimental effect on human and earth environment. So improvement of spray combustion for diesel engines is of urgent necessity. Experiments have been conducted to obtain essential data on spray combustion are influenced by impinging injection in a closed vessel. The effect of the impinging injection on maximum burning pressure, total burning time and mean flame speed is investigated at condition of 300K of initial temperature and 0.1MPa of initial pressure.

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In practical internal combustion engines, where it is very important to achieve the low emissions (CO_2,NO_x,SO_x). It is well known that the lean burn is very useful method to reduce the emissions by control of flame temperature. Therefore, in this study, at low oxygen concentration high-humidity mixture was used for flame temperature reduction. Experiments have been carried out with lean propane-air mixtures to examine the influence of oxygen concentration under high-humidity air and dry air conditions on flame shape and flame speed in a combustion tube. The expaimental results in this study are as follows.: (1) Under low oxygen concentration, the addition of stream is very effective to increase the flame speed. (2) influence of atmosphere humidity on flame speed depends on a fuel property.

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Experiments have been carried out to examine the influence of oxygen concentration in intake air and fuel concentration on flame speed for small gasoline engine by using carburetor and EFI system. The travel time of flame speed front is measured using ionization probes located at different point of cylinder head. The main conclusions are as follows: 1) The flame speed monotonically increases with increasing the engine rotation at any concentration in intake air 2) Mean increasing rate of pressure is not affected by oxygen concentration in intake air and fuel concentration under without load 3) The EFI system can be possible to improve the combustion behavior for small gasoline engine.

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Experiments have been carried out to examine the flame spreading behavior of DME diffusion flame among the burner ports. The pitch distances of the burner port are 7.5mm and 15mm and experimental condition is room temperature and atmospheric pressure. The value of flame spreading speed between pitch distances of burner port is determined by taking the direct photographs with 8-mm video camera. The fuels used are DME, town gas and propane and the evaluation of flame spreading speed of DME is investigated by comparing with those of town gas and propane. The acquisition obtained for the study is as follows that there is no large discrepancies of the flame spreading speed between DME and propane and this means that, for the combustor such as the table tap stove, DME is very effective as alternative fuels of propane and town gas.

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In recent years the study of Homogeneous Charge Compression Ignition (HCCI) combustion is carried out actively because of environmental concerns and drain of fossil fuels. Theoretically, HCCI combustion is highly effective; accordingly it enable to decrease Nitrogen Oxide (NO_x) and Particulate Matters (PM) simultaneously. However, HCCI combustion has the problem that the ignition timing control is difficult and operating range is narrow. In this study, Dimethyl Ether (DME) and methane was supplied to a test diesel engine to operate HCCI combustion. The results of these analyses showed that the mixture ratio of DME and methane influenced combustion reactions in the HCCI combustion. This paper discusses the influence of the mixture ratio of DME and methane in the HCCI combustion.

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Oil-based metal die casting lubricants are sprayed in droplets to a metal die surface before casting. The temperature of appearing the Leidenfrost phenomenon, T_<aLF>, and the evaporation behaviors of the oil droplet on a hot metal surface have been experimentally investigated. T_<aLF> is defined the minimum temperature of appearing the Leidenfrost film boiling. The Leidenfrost temperature, T_<LF>, of an oil droplet is estimated using high speed photographs. T_<aLF> is also determined from evaporation time curves measured by dropping experiments. Both temperatures, T_<aLF> and T_<LF>, for each specimen were good agreement. Changes of evaporation behaviors of mix type oil droplet during evaporation are due to evaporation of volatile compounds.

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In this paper, experimental and numerical considerations were made in order to clarify the thermal deformation mechanism. In the experiment, using several kinds of materials and plate shapes, we observed the bending deformation of the plates during localized heating by TIG welding. It was fonud that all plates were deformed into convex shapes on non-heating side. Thermo-Elasto-Plastic analysis in terms of FE program made by ourselves was also carried out and the thermal stresses and deformations were calculated. The calculated residual shapes of plates were not in good agreement with experimental results in the present stage.

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Structure and heat losses of an evacuated flat-plate type solar collector are discussed in this study. High performance and light weight are features of the collector. Heat losses from the absorber plate to the glass cover and the rear plate were measured and examined under several low pressure conditions from 2.5 to 10^5Pa. The measured result shows that the plateau range in the continuum region between 10^2 and 4×10^4Pa. From the result, the inside pressure level lower than 10^4 Pa is required for the proper operation of the flat-plate collector. Thermal efficiency of the evacuated flat-plate collector was calculated. The compared result indicates that the performance of the evacuated flat-plate collector is higher than that of the evacuated tube type collector in range of ΔT/q_<sun><0.14Km^2/W.

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About a single tube thermosyphon, we performed numerical analysis about a heat transfer characteristic of the condenser section. And we examined it about temperature distribution of condenser section heat transfer surface and influence of distribution of a wall surface heat-transfer coefficient by comparing an analysis result with experimental value of the past. As a result, at the time of charge ratio 90% and coolant temperature 50℃, we got the analysis result that was near to experimental result. We were able to confirm that condenser wall temperature lowered when changed a local heat-transfer coefficient and analyzed it. There was not most of the influence to an average heat-transfer coefficient then.

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The principal issues of Homogeneous Charge Compression Ignition (HCCI) combustion that must be addressed include ignition timing control and expansion of the stable operation region. Detailed analyses of ignition and combustion mechanisms must be undertaken to resolve these issues. In this study, spectroscopic techniques were used to investigate the effects of the residual gas state on ignition and combustion characteristics. Spectroscopic measurements were made of light emission intensity and of absorbance at a wavelength corresponding to the passage of a cool flame. As a result, when a low-octane fuel was used, the heat release rate waveform for HCCI combustion showed evidence of the passage of a cool flame, which was clearly observed in the light emission spectra and light absorption behavior.

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[in Japanese]

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In this paper, we examine the parametrization of all proper stabilizing controllers for multiple-input/multiple-output minimum phase systems. Glaria and Goodwin first gave the parametrization of all stabilizing controllers for the single-input/single-output minimum phase systems. The parametrization by Glaria snd Goodwin has practical difficulties. Yamada overcame these problems and proposed the parametrization of all proper internally stabilizing controllers for single-input/single-output minimum phase systems. We expand the result by Yamada and propose the parametrization of all proper internally stabilizing controllers for multiple-input/multiple-output minimum phase systems.

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In this paper, we examine a design method for a stabilizing modified Smith predictor for non-minimum-phase time-delay systems. The modified Smith predictor is well known as an effective time-delay compensator for a plant with large time delays. Several papers on the modified Smith predictor have been published. However, the parametrization of all stabilizing modified Smith predictors for non-minimum-phase time-delay systems has not been obtained. The purpose of this paper is to propose the parametrization of all stabilizing modified Smith predictors for non-minimum-phase time-delay systems. At first, the definition of modified Smith predictor is given. Next, we propose the parametrization of all stabilizing modified Smith predictors for non-minimum-phase time-delay system which is not necessarily stable.

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A new shift-by-wire system having a stand-by mechanical link with a backlash is proposed. The link directly connects the select lever and the manual lever of the automatic transmission in case of emergency. Thus it is necessary to keep the backlash free during normal operations without generating a force. The angels of the manual lever driven by an actuator should follow the angles of the select lever exactly and quickly. A two-degrees-of-freedom model matching control is developed to meet this requirement. It is shown that the backlash is kept to be free during range select operation.

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This research is on automatic tracking control for vehicles. This note proposes a basic schematic concept of tracking, i.e., "virtual spring-damper connection." We show a method of parameter optimization for the virtual springs and dampers. The numerical simulations with the optimized parameters show that the followers can track the leaders very naturally.

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