Six-stroke diesel engine proposed here has six processes in one cycle, and NO emission is expected to decrease owing to the direct EGR in the 2nd combustion process. However, weak mixing in the 2nd combustion process produced much soot. In this study, the six-stroke diesel engine was operated with low compression ratio in order to reduce NO emission. Moreover, high swirl ratio, supercharging and early injection were applied to promote mixing of air and fuel. As the results, high swirl ratio was effective in the reduction of soot emission. Under high swirl ratio condition, early injection with supercharging was effective in the reduction of soot emission due to well mixing of air and fuel.

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The fuel injection conditions for DME CI engine differ significantly from those of ordinary diesel CI engines, because the physical properties are different from the diesel fuel. The injection pressure is much lower and the nozzle orifice is bigger (<60MPa and =(p0.35, respectively). In this study, the high speed observation of combustion DME spray was performed to understand the differences between DME and diesel spray combustion using high speed video camera in constant volume vessel under engine like pressure and temperature condition. As the results, we found some major differences in flame luminosity and lift-off length. The flame luminosity of DME spray is much smaller than that of diesel flame, which means no soot is formed in DME spray combustion. The flame lift-off length is shorter, because evaporation is very fast and liquid length is shorter. In other aspects, including spray shape, penetration, and flame developing process, no significant difference could not be seen.

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Burning velocity and NOx formation in the combustion of NH_3 mixed with H_2 at different air-fuel equivalence ratios and different H_2/NH_3 ratio were experimentally studied in this research. NH_3 burning velocity increased with increase of amount of H atom in the flame with the addition of H_2. Burning velocity of H_2/NH_3-air changed with the H_2/NH_3 ratio, and it seemed to be highest at the H_2/NH_3 of 0.67. The nitrogen in NH_3 converted to N_2 during the combustion. Small amount of NH_3 converted to NOx and its concentration increased with the increase of H_2/NH_3 ratio.

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In this study, an internal gas combustion engine having a rated power output of lkW was experimentally studied fueled directly by ammonia. As a result, it was cleared that the gas engine was not driven by ammonia alone. However, it was driven by adding methane or hydrogen to ammonia at suitable concentrations so as to control combustion rate. The concentration of ammonia in the gas mixture should be less than 60 percent on the basis of total calorific value. During its stable working, it keeps rotating number at 1950 rpm. Besides, no ammonia contained in the exhaust gas for any stable conditions.

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Recently, compact and high output power sources are needed in small electronic devices with higher performance. Authors have focused on internal combustion engines which have a higher output energy and power. In addition, we have adopted the hydrogen fuel because the power sources with environment-friendly properties are required in the small electronic devices. In this study, the rotary engine (RE) was adopted as the compact power source because it has simple structure and a small number of parts. We developed hydrogen RE (HRE) with displacement of 20cc to investigate the problems in applying hydrogen to compact RE. This engine have been operated with internal mixing method and premixing method with a propeller. And, both rotary engine characteristics were evaluated with an eddy current dynamometer. As a result, in these two fuel supply methods, HRE could be operated for more than 30 minutes with the propeller. In the internal mixing method, HRE had the maximum output power of 1.04 kW, and in the premixing method, maximum output power of 0.72 kW. The maximum output power in the premixing method were 30 % lower than that in the internal mixing method although the operation was stable in the premixing method.

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In order to improve efficiency of small-displacement combustion engine, reuse of useful compositions of exhaust gas is experimented by using newly developed Solid Oxide Fuel Cell. The exhaust gas include trace of unburned fuel, hydrocarbons and oxygen includes some unburned fuel, hydrocarbons, oxygen, and water. Meanwhile high temperature about 973K can be expected at exhaust manifold, if the SOFC system is installed there, electric power can be generated with some steam reforming of these gases. If the energy is collected from the exhaust gas with the reactions, that can provides Lighter AC Generator and battery, and less catalyzing unit to combustion engine. This can derives lighter weight chassis and totally reduction of fuel consumption. In our previous report, it is confirmed that our developed SOFC unit can generate electric power from exhaust gas. In this paper, the power generation experiment in the case of 10 vol% bioethanol fuel is reported.

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A single lightweight engine capable of operating over a wide range of Mach numbers from startup to the hypersonic condition was proposed in our previous reports (Naitoh et al, AIAA paper 2012, Naitoh, submitted as patents, 2010, 2011). This ultimate engine has the new compression system based on colliding super multi pulse jets instead of a traditional turbofan. Computational fluid dynamics shows that this system results in stable compression and combustion. Then, we organize a rotating flat plate, wind tunnel system, supermulti-jets colliding system, combustion chamber, and fuel injection system controlled electrically within the error less than 5.0% for injection amount and then, through fundamental combustion test, we examine whether compression system based on colliding super multi pulse jets is effective or not. We take photographs by varying the temperature of the glow plug. As a result, we get that the critical ignition temperature of glow will be 142℃ for the present prototype engine at a very low inlet Mach number.

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This new piston engine has a potential which results in high thermal efficiency based on the repeat of a compression stage due to colliding super multi-jets with pulsation and a vacuum-like operation due to strongly-asymmetric double piston system. This new compression principle can also reduce the cooling loss, engine vibration and engine noise, because of encasing effect due to the super multi-jets. Therefore, this engine can increase in thermal efficiency drastically. First, computational fluid dynamics shows that this engine system results in stable compression, i.e., increasing in pressure and temperature at super multi-jets colliding point, even at low engine speeds. In the present report, we specifically focus on development of this engine including the air intake and exhaust components, lubricating system, and electrically-controlled fuel injection system. The motoring experiment shows that strongly-asymmetric double piston engine can move smoothly more than l,000rpm of engine speed. Recently, we start the fundamental combustion test.

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In this study, the influence of Hydrotreated Vegetable Oil (HVO) blending on cloud point and pour point of diesel fuel was experimentally investigated. The influence of HVO blending on solidification pressure was also investigated. Pour point and cloud point was measured according to JIS K2269. For observation of pressure solidification process and measuring solidification pressure, a high-pressure vessel with optical access through quart glass window, capable of withstanding up to 200MPa was used. The solidification pressure was defined as the pressure at which freezing content was visually confirmed when the pressure gradually increased. As the result, solidification pressure of diesel fuel and HVO at temperature of 15 deg. C was 100MPa and 170MPa, respectively. Solidification pressure of diesel fuel was lower than that of HVO by about 70MPa regardless of temperature, and was increased with increasing HVO blending. Cloud point was decreased and pour point was increased by blending HVO.

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Autoignition characteristics of PRF90/ethanol blend fuels were investigated under engine-like ambient conditions using a rapid compression machine at an equivalence ratio of 1.0. The numerical analysis based on the chemical kinetic mechanism proposed by Curran et al. was also conducted. Measured ignition delays of PRF90 were almost same as those of ethanol and the simulated ignition delays were in reasonable agreement with those of experiments. The simulated ignition delays of PRF90/ethanol blend fuels were also in agreement with the experimental results. We found that the addition of ethanol decreases the ignition delay as most of the reduction was achieved with an addition of 10mol% ethanol and the ignition delay gradually increases with an addition of over 10mol% ethanol.

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Utilization of bio diesel fuel (BDF) was effective in reduction of PM emission as compared with that of diesel fuel. However, it is well known that BDF produces much deposit on engine components as compared with diesel fuel. Deposition accumulated on the wall of a combustion chamber might cause a decrease of thermal conductivity, and abnormal combustion in the chamber might occur due to a decrease of thermal conductivity. Therefore, it is necessary to investigate the behavior of deposition on the wall in order to maintain stability of combustion in the chamber. In this study, the deposition behavior on combustion chamber wall of actual diesel engine was investigated by using diesel fuel adding fatty acid or fatty acid methyl ester (FAME). As the results, total deposit mass during 20 hours engine operation was lower than that of diesel fuel when the diesel fuel adding fatty acid and FAME were used.

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In order to decrease the smoke emission of coconut oil methyl ester (CME) with 1-butanol, increasing the 1-butanol mixing ratio was tried, and the fuel properties, combustion characteristics and exhaust emissions of the CME/l-butanol blends were investigated using a DI diesel engine. With increase in 1-butanol content (10-40 mass%), the smoke emissions decrease, the ignition delay becomes longer and the HC and CO emissions increase especially at low load conditions. By adding the cetane number improver to CME/l-butanol blend, the ignitability is improved and the 1-butanol mixing ratio can be increased up to 60 mass%. However, the smoke emissions slightly decrease because the premixed combustion ratio decreases due to the shorter ignition delay.

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In order to improve the ignitability of emulsified biodiesel, the effects of cetane number improver (2EHN) addition on the combustion characteristics and exhaust emissions of emulsified biodiesel were investigated using a single cylinder DI diesel engine. The ignitability of emulsified biodiesel is improved by 2EHN addition. The HC and CO emissions reduce and smoke emission slightly increases due to the ignitability improvement. By using 1 mass% 2EHN, the water mixing ratio of emulsified biodiesel can be improved from 15 to 25 mass% and the NOx emission reduces.

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There are strong demands today to further improve the thermal efficiency of internal combustion engines against a backdrop of various environmental issues, including rising carbon dioxide (CO_2) emissions and global warming. One factor that impedes efforts to improve the thermal efficiency of spark ignition engines is the occurrence of knocking. The aim of this study was to elucidate the details of knocking based on spectroscopic measurements and visualization of phenomena in the combustion chamber of a test engine that was operated on two primary reference fuels with different octane ratings (0 MON, 80 MON). The ignition timing was retarded in the experiments to delay the progress of flame propagation, making it easier to capture the behavior of low temperature reactions at the time knocking occurred. Spectroscopic measurements were made at the light emission wavelength and transmitted light wavelength corresponding to those of formaldehyde (HCHO) produced as an intermediate product during a cool flame. Measurements were also made at the light emission wavelength of the OH radical that plays an important role in combustion. As a result, pressure rise by low temperature reaction is considered to be one of the factors affecting knocking intensity.

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In order to detect the combustion state for an individual cycle of every cylinder in a production SI engine, the ion sensor of gasket type was used. The engine was operated under the conditions that the equivalence ratio, intake pressure and engine speed were varied. The parameters obtained from the ion current signal for an individual electrode indicated the cycle-resolved flame propagation. The value of correlation coefficient between the timing of 50% mass fraction burned and the start timing of ion current is very high under every condition. To investigate the ability of the circular type gasket ion sensor, the ion current fraction accumulated, ICFA, was defined from the summation waveform of ion current for gasket ion sensor. It was found that the rate of heat release for individual cycle is presumed by using ICFA of the circular type gasket ion sensor.

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A near-IR laser absorption spectrometer using a technique of wavelength modulation spectroscopy has been used to the measure ammonia (NH_3) and nitrous oxide (N_2O) in automobile exhaust. NH_3 and N_2O were detected at the line center of 6548.60 cm^<-1> (2v_3, ^p_sP(4,3)) and 6549.56 cm^<-1> (3v_3, P(28)e), respectively. To prevent NH_3 from adsorbing on the cell, the cell temperature was set at 373 K. The effect of CO_2 included in automobile exhaust on the concentration of NH_3 and N_2O was evaluated. The air-broadened half-widths of NH_3 (^P_sP(4, 3)) absorption line and the CO_2 - broadened half-widths of NH_3 (^P_sP(4,3)) and N_2O P(28)e absorption lines at 373 K were obtained to be 0.0673 ±0.0101 cm^<-1> atm^<-1>, 0.0941 ±0.0141 cm^<-1> atm^<-1> and 0.0709 ± 0.0106 cm^<-1> atm^<-1>, respectively. Based on these values, the differences in NH_3 and N_2O concentrations between 0% and 16% CO_2 concentration are -2.2% and -1.1%, respectively, which leads to the precise measurements ofNH_3 and N_2O concentrations in automobile exhaust.

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Velocity distributions of the spray droplets and ambient gas in a non-evaporating Diesel spray were measured by the LIF (Laser Induced Fluorescence) - PIV technique which adopts two CCD cameras. Simultaneous measurement of the both velocity distributions inside the spray could be made in the particular region 4-5mm inside from the spray tip. The axial velocity of the spray droplets is much larger than that of the ambient gas at 4-5mm inside from the spray tip. The axial velocity of the spray droplets becomes the similar value as the ambient gas in the region l-2mm inside from the spray tip. In this region, the spray droplets velocity vector changes its direction to the radial (outward) direction, whereas the ambient gas velocity vector keeps the axial direction (downward).

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The enhancement of drop-wise condensation heat transfer was examined for steam at 0.1 MPa by using grooved-heat transfer surfaces. The drop-wise condensation was attained by plating the surface with gold. In the case that the surface was flat, the drop-wise condensation heat flux was of course much higher than that of the film-wise condensation. The drop-wise condensation heat flux on the grooved heat transfer surface that was defined hypothetically by the flat surface was larger than that of the flat heat transfer surface. When the top and the wall of the groove were plated with gold, the hypothetical drop-wise condensation heat flux was highest. Next was the case that the top, the wall and the bottom of the groove was plated and third was only the top of the groove was plated. It appeared in the recorded high speed video images that condensate drops on the top and the wall of the groove was pull down to the bottom of the groove. As a result of it, the bare area that was exposed to steam seemed to increase. When the groove size was increased from 2 mm to 3 mm, the enhancement of the drop-wise condensation heat flux was mitigated.

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This paper describes the development of annular-type combustion using reflunet flow for ultra-micro gas turbine. As the definition of an ultra-micro gas turbine, we considered it as the type that applied to the condition of less than 20mm for the impeller diameter. Recently, commercialization of portable power generation system that is composed of an ultra-micro gas turbine engine is expected. As background, the ultra-micro gas turbine power generation system has also some benefits as availabilities for a power generation in an emergency such as a disaster, or for a power source that can support a wide variety of fuel. In this study, the subject is to development of an ultra-micro gas turbine engine characterized by palm size. Design concept of the combustor and flame characteristics using micro-nozzle are discussed in this paper. As a result, we obtained the steady-flame conditions by fuel flow rate, and also a flow-simulation result as a design guideline.

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The aim of this study is to elucidate effects of atmosphere pressure in combustion chambers, fuel injection pressure and injection hole number on exhaust characteristics from diesel combustion. 2-color radiometry thermal imaging system with a high speed digital camera was used to measure flame evolutions in the combustion chamber of a rapid compression machine. The atmosphere pressure was raised up to 8 MPa to simulate supercharging conditions. An increase in the number of injection hole increases the NOx concentration of exhaust gas through the flame area enlargement. As the atmosphere pressure rises, the combustion period is elongated due to the decrease in the amount of mixture formed before ignition, which leads to the slight increase in EINOx. The injection pressure rise locally enhances the NOx production in expanded high temperature regions while suppressing the total NOx production through the short residence time of the flame. The difference between EINOx with different injection pressures is therefore quite small.

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A novel rotational internal combustion engine has been investigated in this study. No eccentric rotational component is used in this engine, resulting in vibration-free operation. The engine consists of rotor casing and two types of rotor; cycloid rotor and trochoid rotor. The shape of the cycloid rotor is characterized by epicycloid surface, and the trochoid rotor also superior-epitrochoid surface. In this paper, first, the typical configuration was shown. Next, a procedure for designing the rotors were described in detail. Furthermore the design drawing and appearance of the prototype engine were given. Its cyclic behavior, the time variations of the chamber volume and the estimated pressure were also indicated. Additionally the flame behavior in the working volume of the prototype engine driven in motoring condition, was presented. Finally the compactness and S/V ratio of the engine was investigated.

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Bio fuels have been used as an alternative fuel for fossil fuels. Currently, the bio fuels such as bio diesel and bio ethanol has been used for the fuel of the reciprocating engines. However, the using of bio fuels for gas turbine engines are not active yet. In this paper, we discuss the type of bio fuel and the adaptability of it for gas turbine engine. At first, we revealed the concentration dependence of viscosity of the mixed fuel of ethanol and bio-diesel fuel using a rotational viscometer. Then we investigated the performance of turbine engine which adopt the ethanol/diesel fuel mixture as fuel. As a result, ethanol/diesel fuel (mixture ratio 5:5) was close to the fuel JetA-1 which has been currently used, on the performance but there were many Particulate Matter in the exhaust gas.

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Fluidized bed gasifier can handle fuel more easily and operate at low temperature. However, a lot of tar is generated. This new gasifier, which is called a fludized bed gasifier with triple-beds and dual circulation, was proposed. Main features are the adoption of a triple-beds structure, the separation of circulation paths for tar-absorbing particle and fuel. Pyrolyzer and gasifier each have a two-stage fluidized bed. In the pyrolyzer, tar is formed together with gas produced during pyrolysis of the fuel in the lower stage, and the tar is absorbed by the tar-absorbing particle in the upper stage, that is, tar can be treated in the gasifier. The inhibition of char gasification can be reduced because the pyrolyzer and the steam gasifier are separated. Additionally, since two circulation paths each have an independent combustor, mixing of the tar-absorbing particle with the bottom ash can avoided. Running cost can be greatly reduced.

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Half of coal reserves are low grade coal which has low calorific value. The low grade coal must be used effectively to utilize the coal resource over a long period of time. Brown coal has a lot of moisture in inside and about 2/3 of mass is moisture. When the brown coal burns for fuel of power generation, latent heat of steam evaporation causes thermal loss. For this reason, decrease of thermal efficiency occurs for brown coal utilization. Since the brown coal has low degree of carbonization, spontaneous ignition and explosion easily occur during drying process. Although we want to establish a drying technique of brown coal, the details of drying property of brown coal are not clarified and drying time of brown coal cannot be predicted exactly. In the present study, numerical model of single particle of brown coal in hot air flow was constructed and the drying property of brown coal was investigated.

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Co-generation systems and district heating and cooling have been applied to urban areas for achieving a low-carbon society. However, CO_2 emissions from operations division including commercial buildings are still on the increase. Hence research of micro grid is conducted as one of the countermeasures for achieving a low-carbon society. In case micro grid is introduced actually, it is facilitated by choosing a region where district heating and cooling was already applied. Thus in this report, a combined system composed of micro grid and district heating and cooling was considered. The combined system in this study interconnected 3 commercial-scale utility customers with different electric demands and thermal demands. Annual CO_2 emissions in each condition were minimized by using a numerical software GAMS/BARON.

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A Japanese construction machine industry maker proud of the trust of the world top-class but, in the rising nation which the companies make much of as a market, a Hydraulic pressure construction machine operates for 24 hours. A crack happens for it in the Hydraulic pressure source pipe flange part of the machine and causes the problems such as declines of the work efficiency. In this study, it is intended to prevent an occurring crack by a control on vibration device and evaluates the control on vibration effect of the device at the development stage. In the study of damping properties using the device vibration hydraulic fittings system, it was confirmed by experiment to suppress the damping of mouth metal part of the pipe and return discharge pipe of the hydraulic power source pipe to do with each other under reduced pressure and the pressure, shows the results obtained below. The inclusion of the damper Cu ball 3 [mm], of 100[g], as compared with the case without the device, it becomes a peak gain value of 7.66[dB], and could 9.3 [dB] low that from the peak value in the case of a single.

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In late years, the noise by speeding up vehicle in the car increases, and spoil comfortable environment in the car. In the inside of car , the noise of 100〜2500 [ Hz ] is the problem . This study's theme is Noise reduction in such a high speed vehicle by using a lot of Micro - size granular materials. An experimental device is a vibrating machine furnished with the measure of iron to which the cylinder was attached. I put the inside granular many materials of this cylinder. And I vibrate equipment and count the resonance frequency of a measure. And I choose the particulate material reducing vibration of the frequency. In this study, the granular material reduced up to about 9[dB] vibration in a low spectrum.

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In this study, a finger and wrist motions are discriminated using EMG on forearm to move the power assist glove, which can assist grasp. A finger and a wrist are moved when various muscles on a forearm contract simultaneously. Therefore, a finger and a wrist motions must be discriminated to detect a human intention to move a finger. By introducing Self-organizing maps (SOM), discrimination of these motions can be improved. In this paper, the effectiveness of discrimination method using SOM is verified experimentally.

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A way of identifying varying damping ratios C, in the liner vibration theory of a single-degree-of-freedom system is studied. Free vibration tests on the damped single-DOF system are conducted using a commercial vibration apparatus. The magnitudes of a damping force are controlled contactlessly by an electromagnetic damper installed in the apparatus, and the corresponding damping ratios are identified using theoretical formulas and a numerical technique. It is shown that the damping ratio can be expressed as a cubic function of a damping current. A relation between the damping ratio and the magnetic flux density is discussed.

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It is known that piezo actuator changes its hysteretic property as velocity of the required motion changes.This kind of hysteresis is often referred to as the rate-dependent hysteresis.This paper presents a development of a numerical model capable of representing rate-dependent hysteresis.The presented model is based on the classical Preisach model and it will be shown that rate dependence is incorporated into the model by employing a new function to augment the distribution function.Comparison between the model output and the experimental response against input signals containing a single frequency and various frequencies will be shown to indicate the validity of the model.

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Axle weighing system measures each axle weight of in-motion vehicles.The weighbridge of the axle weighing system is detector part of the system and consists of weighing platform and loadcells.It has the length of 76 cm in traveling direction of a vehicle which is nearly equal to the diameter of a tire,to avoid measuring two axle weights at the same time.A method has been studied for estimating axle weights by processing the weight signal from the axle weighing system to improve the accuracy of measured axle weights.The method have been applied to in-motion vehicles at the velocity of less than 15km/h and axle weights have been obtained in high accuracy.However,the examination of the accuracy of estimated axle weights of in-motion vehicles with higher velocity has not yet completed.To examine and improve the accuracy of the estimated axle weight,a miniature instrumented vehicle and a miniature weighbridge have been developed.Then,the miniature instrumented vehicle,and weighbridge are described in the paper.

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Carts are used in various situations to reduce fatigues and efficiently carry baggage.An automatic-tracking cart has been developed in recent years.Vibration suppression and attitude control are required to carry everything in everywhere.Vibration suppression and attitude control of the cart uses three linear actuators and three-degree-of-freedom parallel links.This system is heavy when it is equipped the automatic-tracking cart.This paper proposes a new suppression and attitude control system of cart.This system uses a DC motor and a pantograph jack as an actuator and control attitude from y axis acceleration of an acceleration sensor.Reduced order model preserving stability margin is used for attitude control.Some experimental results prove that this system is effective in attitude control.

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This paper proposes a new control system that actuates a Voice Coil Motor(VCM) for a chasing and vibration dumping robot.This system has a main loop that controls positions of the VCM and a minor loop that controls vibration dumping of the VCM.Furthermore,a transfer function that translates acceleration to position is set between the main and minor loops.The main loop controls position in low frequency range and the minor loop controls vibration in high frequency range.These proposed transfer and control realize a liner control system using a position sensor and an acceleration sensor at the same time.

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In this study,we treat the vibration of cable-stayed bridge,as one of a structure supported by cables.For analysis,we make a simple analytical model of cable-stayed bridge composed of a girder and 4 cables.In this analytical model,cable tensions act on the girder,and displacements of the girder give the influence on the vibration of the cables.We derive equations of motion of the girder and cables,and analyze coupled vibration of them by numerical simulation.Especially,we investigate time history response and frequency of vibration of both the girder and cables,then estimate the couplingeffects between the girder and cables.For investigating coupled frequencies,we use Fast Fourier Transform(FFT).In the numerical simulation,we focus on sag-span-ratio,one of parameters of a cable.We vary the value of sag-span-ratio in the simulation,and study its influence on the coupled vibration.

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The spent fuels from nuclear power stations are stored in a cask until reprocessed.It is concerned that the cask turns over when an earthquake occurs,because it is generally freely standing on a horizontal floor.This study investigates the rocking motion of a cask experimentally and analitically using CAE software named MATLAB.When earthquake occurs,rocking and sliding motion will occur at the same time,however we consider only rocking motion.A cask is huge and the weight is about 157 tons,therefore we make a reduced scale model.The scale factor is 1/1000 and the weight is about 15kg.In the experiment,we excite the experimental model by applying initial angle or sinusoidal wave,and rocking angle is measured.The experimental results are compared with the analytical ones to check the validity of the analytical method.In the analyses,we vary the coefficient restitution,and study the validity of the analytical model on restitution coefficient.Next,we suggest Gyro system in order to prevent the rocking motion.This Gyro system gives the cask Gyroscopic effect,thus the rocking motion can be reduced in analytically.Expwriments are conducted using a gyrosystem model to examine the validity of simulation model.

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In this paper,the authors have developed a new type of horizontal seismic isolation system which has large effect of vibration isolation for ordinary earthquakes and suppresses the resonance of the isolation system due to long-period seismic ground motions.This seismic isolation system is composed of a pantograph mechanism and coil spring and two slide rails.Installing the pantograph mechanism to suppress the relative displacement at resonance.The trial seismic isolation table was made,and the effects of vibration suppression of the isolation table were discussed experimentally and numerically.Experimental results and Calculation results showed the pantograph mechanism has a relative displacement suppression effect.

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This study is aimed at evaluating the variation of maximum response of target tanks and piping systems subjected to the artificial earthquake motions in industrial facilities.In the seismic design criteria for high-pressure gas equipment,these structures did not take into account the plastic deformation until it was revised in 1997.However,from the viewpoint of safety of these facilities during earthquakes,the seismic design considering the elasto-plastic response is also required.In this study,based on the target response spectra which are defined in the seismic design criteria,ground characteristics a target response spectrum,the artificial earthquake motions are simulated with the envelope function representing the non-stationarity of the earthquake motion.These earthquake motions are subjected to the SDOF system having the bilinear restoring force and then the effects of ground characteristics and main duration of motion on the variation of the maximum responses are examined.

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This paper presents a damping control and a transfer control with an omni-directional mobile robot.The robot moves to the all directions by using three omni wheels,and a spherical pendulum is considered as a carrier.The damping and transfer control system consists of a feedforward control part and a feedback one.In the feedforward control part,the damping control of the spherical pendulum is carried out by shaping the acceleration of the robot with a notch-filter.In the feedback control part,an optimal servo is used to correct the position of the robot and to damp the amplitude of the angle of the pendulum.A weighting matrix of the optimal servo is optimized by using a genetic algorithm.Transfer path is a straight line on a plane.The usefulness of the proposed control system is verified through simulation and experiment.

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This report proposes a floating type disk brake model,and a real number type immune algorithm(IA).It aims to find an operation which can avoid an obstacle,which is found in colliding distance only by a braking operation,by a combination of steering and braking in the highway.IA has been used to find plural solutions of operations.The effectiveness of the braking model is verified through a sudden braking simulation.A real number type expression is adopted in substitution for a conventional binary type as a coding method of IA.The usefulness of the proposed methods is demonstrated through an emergency avoidance simulation with a directed final yaw angle of a vehicle.

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In this paper,a damping control by using an active vibration reducer of 6-DOF parallel link type.Sloshing in a cylindrical container is caused by transfer acceleration.Sloshing is represented by a spherical pendulum model.The spherical pendulum model is used to design the damping control of sloshing.The damping control of sloshing is carriedout with a reference model following control and an optimal servo control.The reference model following control isused to suppress the higher mode sloshing.The optimal servo control is applied to damp(1,1) mode sloshing.The simulation model applying the control system has(1,1) and(1,2) mode sloshing.The values of the parameters of the reference model following control and the weighting matrix of the optimal servo are optimized by a genetic algorithm(GA).The usefulness of the proposed control system is verified through simulation.

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Man walks using the Natural vibration of musculoskeletal systems,such as a way of a leg or an arm,and torsion of the body.Passive dynamic walking is what imitated such persons walk,and it performs rhythmical movement which employed the mechanism characteristic efficiently.We produced the test prototype consisting of the waist and two legs by old research,and it realized the passive walk.However,in this test prototype,the flexibility of leg structure,etc.are not similar with people,and the aspects of the walk also differ.Application of the future of a passive walk was considered,people's walk analysis was conducted first,the mechanism of the walk was traced,the test prototype which imitated people's leg structure was produced,and this research aimed at realization of the 2-pair-of-shoes passivity walk near people.

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This paper treats the generated forces between the roller and the table,when a roller is rolling on the powdered coal spread over a table.The force ratio of the horizontal and vertical is investigated for the different distribution of the particle size and the different moisture conditions of the powdered coal.We found that these forces depend on "the running velocity of the roller","the powdered coal's particle size" and "the quantity of moisture in the powdered coal".To examine dynamic characteristics of the generated force, we employ a viscoelastic model with a serial spring and dashpot. For the difference moisture conditions, the model parameters are identified using the least squares method. The identified model parameters depend on "the running velocity of the roller" and "the quantity of moisture", but are not always identical to the experimental results.

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In order to know effects of friction bearing type on response characteristics of base isolation system,characteristics of base isolation system composed of only new friction bearing are investigated by excitation experiment,and are compared with the existing system.The friction bearing with the ball embedded in a cylindrical sponge can control damping ratio without change of natural frequency.Compared to peak acceleration amplitude and RMS between the existing and the new system,the new system in case 4 indicates good reduction.From a spectral point of view,thesystem in case 4 shows good reduction at the frequency bands over 1Hz.

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The noise reduction technique for the data measured simultaneously at multiple points is proposed.Given the fact that the measurement vibration data are superposition of limited number of modal responses,all the frequency responses can be expressed as superposition of a small number of common frequency characteristics.In addition,the deformation modes that change with frequency can also be expressed as superposition of a small number of common deformation patterns.On the contrary,it can be considered that the deformation modes which appear only in specific frequencies and the frequency characteristics which appear only at specific points are noises.Singular value decomposition is employed to extract the common components,and the noises can then be eliminated through the synthesis of these components.

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This paper describes the vibroacoustic coupling between the structural vibrations and internal sound fields of thin structures. In this study, a cylindrical structure with thin end plates is subjected to a harmonic point force at one end plate and a natural frequency of the end plates is selected as the forcing frequency. The resulting vibroacoustic coupling is then analyzed by theoretically and experimentally by considering the dynamic behavior of the plates and the acoustic characteristics of the internal sound field as a function of the cylinder length. The length and phase difference between the plate vibrations, which maximize the sound pressure level inside the cavity, are clarified theoretically. The theoretical results are validated experimentally through an excitation experiment using an experimental apparatus that emulates the analytical model.Moreover, the electricity generation experiment verifies that sufficient vibroacoustic coupling can be created for the adopted electricity generating system to be effective as an electric energy-harvesting device.

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This paper describes the vibroacoustic coupling between the structural vibrations and internal sound fields of thin structures. In this study,a cylindrical structure with thin end plates is subjected to a harmonic point force at one of its ends.A natural frequency of the end plates is selected as the forcing frequency,causing the one end plate to vibrate in high-order mode.The resulting vibroacoustic coupling is then analyzed theoretically and experimentally by considering the dynamic behavior of the plates and the acoustic characteristics of the internal sound field as functions of the cylinder length and plate thickness. The theoretical results are validated experimentally through an excitation experiment using an experimental apparatus that emulates the analytical model.

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We survey a difference with the conventional modeling technique,a characteristic using the.modelica language that we examined about the design using the modelica language and analysis to examine the design in the multi-domain and analysis and dynamics,then,examine analytical technique and,in this study,give an outline about an underlying examination matter on using it.

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This study did the thing that we examined in the design in multi-domain constructed at plural places and the analysis with an aim,and we considered it,and,specifically,the examination using the modelica language examined a facility model including a comparison with other modeling technique including a calculation result example in themodelica language that we considered in the design analysis following former this report.

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This paper deals with the gear rattle of helical gear system,which generates in automotive.By introducing the mesh stiffness variation and tooth profile error into the equation of motion of one pair of helical gear system,and by considering the real meshing of tooth,the influences of the mesh stiffness variation,tooth profile error,and torque variation on the rattle are studied by the numerical analysis which is called shooting method.As a result,the followings were made clear.(1) Because of the interaction of the torque variation,the tooth profile error,and the mesh stiffness variation,large amplitude vibrations occur in low frequency region.Those are chaos.(2) The higher-harmonic resonances also generate because of this interaction.Those vibration amplitudes are larger than those in the case without tooth profile error.(3)Because of the tooth profile error and the torque variation,the real messing of helical gears in the rattle becomes complicated.

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We propose operational transfer path analysis for structure subjected to floor vibration and experimentally examine a vibration transfer path from the floor.The analysis needs a kind of excitation distribution for the structure but it is very difficult to prepare the many exciters on the structure.For that purpose,an additional mass is set up on the structure because it is easy to use inertia force of the additional mass as excitation force.The example where the additional mass is applied to a double floor structure is demonstrated.

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