Lately, surface modification by plasma is one of the study which attracts a great deal of attention. It is known that surface energy of the glass or hydrophilic property on polymer increases with the application of plasma. We investigated the surface modification for the windshield in order to eliminate the windshield wiper of automobiles. The plasma application on windshield reduces the contact angle of less than 5 degrees. The wettability on glass surface was not affected by plasma exposure time, voltage and flow late. The other finding is that the plasma treatment followed by the hydrophobic coating showed the superior hydrophobic property for about 4000 wiper strokes.

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The gas flow rate for hazardous air pollutant emissions is generally high and their concentrations are low (in ppm levels). When we try to treat the high-flow-rate and low concentration gas, the size of the equipment becomes large and the total operating cost is high. The objective of this study is to convert the high-fnow rate and low concentration gas into the low flow rate and high concentration gas by desorbing the absorbed gas on pellet using nonequilibrium plasma. In this paper we focused on NOx to examine the condition which was needed for NOx desorption.

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Two-stage plasma and chemical reactors have been developed for complete NOx and SOx removal. The nonthermal plasma is used to oxidize NO to NO_2 and NO_2 is reduced to N_2 and Na_2SO_4 using Na_2SO_3 or Na_2S scrubbing. And SO_2 is reduced to Na_2SO_3 using NaOH. This hybrid process was able to achieve nearly 100% NOx and SOx decomposition with low specific energy density and minimum reaction byproducts. A series of experiments were performed to quantify all the reaction byproducts such as N_2O, CO, HNO_2, HNO_3, NO_3 and to evaluate simultaneous removal of NOx and SOx system.

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The plasma combined electronic air cleaner which composed of collection of submicron particles and decomposition of acetaldehyde and ammonia was investigated, offensive odor of tobacco smoke. For acetaldehyde decomposition, about 90% of decomposition efficiency was obtained with the use of nonthermal plasma under dry condition. For ammonia decomposition, 100% of decomposition efficiency was obtained with the use of nonthermal plasma on the optimum condition. The combination of electronic air cleaner having more than 99% collection efficiency for 0.3 and 0.6μm and nonthermal plasma technology leads to the breakthrough of the conventional indoor electronic air cleaner technology.

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A new fatigue testing method was proposed by which fatigue cracks can be initiated and propagated in a film adhered to cover an elliptical through-hole in a base plate subjected to push-pull cyclic loads. This method was based on Eshelby's elastic inhomogeneity model. According to this model, when an inclusion in an isotropic infinite body is ellipsoidal in shape, the stress and the strain within the ellipsoidal inclusion are uniform. It follows from this that a film corresponding to the inclusion has a uniform stress at all points within it. Using this method of film fatigue testing, rolled iron films annealed at 873K and 1073K were fatigued with a stress ratio of R=0, and then the effects of the rolling direction and annealing temperature on crack initiation and propagation behavior were studied.

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Ab-initio and classical molecular dynamics simulation technique are used for studying the fracture phenomena of β- silicon nitride single crystal and an interface between aluminium/aluminium nitride. The fracture toughness, and stress distribution near crack tip of the single crystal are estimated and are compared with experimental data and linear elastic solution, respectively. Intrinsic strength of the interface is also estimated from results of ab-initio molecular dynamics simulation.

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Since fatigue crack growth phenomenon is considered to be intrinsically localized, microscopical observation is an effective technique to elucidate the fatigue crack growth mechanism and large number of microscopic studies have been made. In this study, growth behavior of fatigue crack was observed by using an atomic force microscope (AFM), and crack growth mechanism was discussed.

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Tensile test of a cross-woven one-ply SiC fiber-reinforced SiC composite was carried out in a scanning electron microscope. This test allows detailed observation of the fracture behavior on the side and upper surfaces of the composite and the emphasis here is on the transverse cracking behavior. Transverse cracking patterns and other associated fracture events and their sequences are identified. Two-dimensional micromechanical models are developed to investigate the transverse cracking behavior. Potential functions describing the mechanical responses of the fiber-matrix interface and matrix are introduced and are then embedded into finite element cohesive zone models. It is shown that the model reproduces fracture sequences of debonding initiation, separation, and transition to neighboring interfaces, and formation of a main crack within a unified reasonable framework. Significance of the experimental and numerical results is given.

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Since the surface morphology of materials can be observed with atomic-scale resolution, scanning atomic force microscopy (AFM) is a powerful technique to study mechanisms of fatigue and fracture of solid materials. In the present study, slip-band formation and fatigue crac-initiation processes in α-brass were observed by means of AFM. The depth of the intrusion drastically increased with its outgrowth to a crack. For crack-initiation from slip-band, the intrusion depth took a critical value, which is given as a function of the slip-band angle. For crack-initiation from grain boundary, however, stress concentration at grain boundary, which induced by pile-up of dislocations should be considered.

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The effect of porosity and worked layer on small fatigue crack propagation behavior was investigated for sintered steels. Reversed plane bending fatigue tests were conducted and small fatigue cracks were observed by means of plastic replica technique. It was found that worked layer inhibited fatigue crack initiation and crack growth. On the other hand, improvement of porosity had small effect on crack initiation, while crack arrest was remarkable in the low porosity sintered steels.

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Corrosion fatigue crack initiation process of a high-strength aluminum alloy, 7075-T651 was observed by means of a scanning atomic force microscopy (AFM). Plane bending fatigue tests were carried out either ill air or in 3% NaCl solution. The fatigue strength in aqueous environment was much lower than that in air. Grain boundaries around specific grains were preferential site of anodic dissolution, and cracks were initiated from these grain boundaries.

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The present authors proposed a method for predicting fatigue lives of a two-dimensional crack propagation in residual stress fields, by making use of the crack propagation behavior expressed in terms of effective stress intensity range, and of effective range ratio U expressed in terms of stress ratio. Extensions of this method to three-dimensional surface and corner cracks have been made. In this paper, the proposed method of prediction was applied to three-dimensional slant and hole-corner cracks by using finite element method. The amount and direction of crack extension were evaluated at each point of the crack front to simulate complex change in the three-dimensional crack shapes in actual structures. The effects of residual stresses and contact stresses were examined. The applicability of the method was demonstrated.

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Two dimentional DDD simulation is applied to analysis of the fatigue crack tip field under mode I cyclic loading. Change of stress distribution around the crack tip and structure formed by dislocation movement are analyzed. The equivalent stress distribution obtained by asymptotic solution for rigid plastic field is compared with the results of DDD simulation.

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The surface wave velocity, C_R, depends on the stress, therefore, it is possible to evaluate the stress by using the C_R. The measured value of C_R is determined by V(z) curve obtained by the scanning acoustic microscope (SAM). But the C_R is influenced by the surface roughness, R, of sample, therefore it is problem to evaluate the stress by using the obtained C_R. In this paper, After the surface of sample was polished with emery paper, the R and the C_R were measured. And the effect of the R on the C_R was examined. As a result, the relation between R and C_R was obtained.

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When an ultrasonic wave reaches an interface between two solid media, four waves are generated by reflection, refraction and mode transfer. This paper discribes the simulating method of the received waveform propagated though an interface between two media by using the ray model. A simple analytical model composed of cylindrical aluminum and epoxy resin is prepared for this simulation. Effects of sonic damping, partition of energy and phase are considered in the analysis. And gaussian distribution is assumed in order to represent the intensity distribution formed by sonic field. Simulation results of the waveform are well agreed with the actual experimental results that are obtained using the ultrasonic measuring device.

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Application of highly preheated air combustion to industrial furnaces is one of the most attractive measures to save energy as well as to suppress pollutant emissions in combustion industry. One of such applications is a regenerative furnace. We constructed a simulation model of alternating-flow-type regenerative furnaces to optimize their design parameters and operating conditions. We calculated heat exchange characteristics of heat regenerators using this model.

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In order to destruct the volatile organic compounds (VOC), Babcock-Hitachi K. K. has been developing the regenerative catalytic oxidizer system (RCO). The regenerator in RCO is one of the most important components, which is required high heat transfer and hydrodynamic characteristics. Lath plate type regenerator was used because of enhanced heat transfer, and its heat transfer and pressure drop were measured by means of single blow method and manometer respectively. Performance of honeycomb type regenerator was also examined and compared with that of lath plate type.

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In resent years, the emission control technology of volatile organic compounds (VOC) is seriously required. Babcock-Hitachi K.K. has been developing the regenerative catalytic oxidizer system (RCO) that can provide the VOC destruction and high energy efficiencies under lower temperature, associated with catalytic oxidation. The main features of the RCO equipment are a simplified rotary distributing valve, the catalysts of poison resistant by halogenated compounds and the regenerators with the enhanced heat transfer. This paper describes the elemental studies and the initial performance of this equipment.

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Mechanisms of dioxins formation and emission during combustion process of municipal solid wastes has been discussed. In this study, effects of Cl, Ca, Na, Cu, Fe, S on dioxin emission have been studied by using a small fluidezed bed combustor designed to simulate the combustion process in a municipal solid waste incinerator.

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An experimental study has been carried out to obtain the detail information needed for the deep understanding of the combustion process of an LCO. There were a great many aromatic compound in the LCO. The primary attention was toward the effect of the technique of combustion. Concentration of nitrogen oxides, carbon monoxide and smoke scale measurement in exhaust gases were made of the LCO burning with liquid fuel compact boiler. LCO and kerosene was used as a fuel with diffusion burner, prevaporized burner and prevaporized premixed burner. Prevaporized burner generate small amount of nitrogen oxides. Prevaporized premixed burner generate a little amount of carbon monoxide and smoke. The effect of the proper technique of combustion was revealed.

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It is important to use the waste heat efficiently for energy saving. An absorption refrigerator is efficient as the thermal utilizing equipment of the waste heat. Multi-effect absorption refrigerator is efficient to the improvement of the performance, but it needs higher temperature heat source than single-effect. In order to decrease heat source temperature, a hybrid system with a steam compressor at the exit of low temp. regenerator is supposed. In this paper, we report calculated results on the performance characteristics of the hybrid-type double-effect absorption refrigerator.

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Reaction of hydrogen and oxygen mixture in compressed water had been studied based on the principle of corresponding states and the gas phase reaction mechanism. Calculations have been carried out for the cases of heating the mixture of water, hydrogen, and oxygen under the constant volume. The results show that reaction starts at the temperatures higher than 760 K. It is also pointed out that hydrothermal reaction may enable the control of the ignition processes in diesel combustion of the hydrogen and oxygen mixture.

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In this research, we have developed new gas turbine cogeneration systems. A key technology is adapting steam injection to a gas turbine that has two-stage combustor. In this system, a high-level steam generated from the exhaust heat recovery boiler is injected into the first stage gas turbine. A condensing heat exchanger is installed to recover the latent heat of steam in combustion exhaust gas. As stated above, the significant improvement of power output and the total thermal efficiency can be expected. To realize this system, it is important to determine that the conditions for stable combustion in the case of the low-oxygen atmosphere and the high-level steam injection are determined. We experimentally investigated the characteristics of combustion, and examined the NOx formation from this system by numerical simulations with detailed chemical kinetics. Furthermore, we designed of 2MW class gas turbine system and compared the primary energy consumption of this system with that of ordinary systems. As the result, we clarified that this gas turbine system of high efficiency and low-NOx emission will be able to be realized and contribute energy saving.

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Influence of combustion-parameters, i.e. air-ratio, temperature of preheated air and recirculation of exhaust-gas, on the heat-absorption in combustion-chamber of boilers is analysed on test results of a small furnace. As result, Influence of these parameters on fill-factors AF/Aw of the Yamazaki-method is obtained, therefore, the fill-factor AF/AW considered these factors should be used on the Yamazaki's calculation.

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Cluster formation and disappearance (fracture) process is investigated by numerical simulation, in which theory of molecular-level mechanism is merged. Smoluchowski's equation about the density of cluster size distribution is solved both with ballistic model and with Brownian model. It is found that the most probable size of Brownian cluster is almost the same as that of ballistic cluster. Population of the most probable size, however, varys because of difference in kernel (reaction rate) evolution.

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Relation between porosity and mechanical properties of Al thin film sputtered on Si substrate is investigated by molecular dynamics simulations. MEAM potential is used in the Si-Al diatomic system. The growth of Al film on Si substrate is simulated. Deposited films include porosity on their surfaces and indicate amorphous configuration. The Si-Al system is loaded in the parallel or vertical direction against the substrate surface simulated results on the Al deposited Si system are compared with those on an artificial crystal film system. The difference in deformation behavior between deposited and crystal films is clarified in this paper.

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A quantum molecular dynamics method based on the density functional theory is applied to an analysis of oxygen adsorption on Al(111) surface. This method treats the dynamical interaction effects between multi-electrons and atoms. It is shown that the adsorption mechanism depends on adsorption site and drastic charge reconstruction occurs on adsorption process.

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Behavior of liquid near solid (metal) wall in molecular level is studied by newly developed nonequilibrium molecular dynamics method. In the method, stochastic inflow boundary condition and free outflow boundary condition are adopted. Generation of flow in the Lennard-Jones monatomic-molecular system are verified using perfectly fixed wall model. Further investigation and consideration are performed using a model with nitrogen molecule as a rigid rotor and with non-contaminated aluminum thermal wall. It is found that, when nitrogen molecules are flowing attaching to aluminum surface being heated, temperature of liquids is lower than that of solid wall and the rotational temperature is slightly higher than the translational temperature.

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This study is intended as an optimization of material compositional profile in functionally graded hollow sphere which has two-dimensional nonhomogeneous material properties in the radial and meridian directions and is subjected to an axisymmetric heat supply. Numerical solutions of temperature change and axisymmetric thermal stress under the steady state are obtained for the functionally graded hollow sphere which has two-dimensional nonhomogeneous material properties by making use of finite element method. The optimal two-dimensional material compositional profile is found for the functionally graded hollow sphere so as to minimize the ratio of thermal stress under the steady state to strength of material by using genetic algorithm.

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This paper describes a structure design of uniform strength using cellular automaton. We use the finite element method to solve the two-dimensional elastic problem. Considering the elements of the finite element method as the cells, each cell changes its thickness using the local rule with the states of the cell and the surrounding cells. In this paper, the improvement of local rule, such as a thickness limit, is especially examined.

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For solving inverse boundary value problems, over-prescribed boundary values have been used. In the present study boundary values on the incompletely prescribed boundaries are estimated using the inside measurements. The inverse boundary value problem is treated for two-dimentional elastostatic body. Application of the boundary element method reduces this inverse boundary value problem to the solution of matrix equation. This matrix equation is severely ill-conditioned because of the ill-posedness of the problem. Regularization is therefore necessary to obtain a good solution of this matrix equation. A selection of the effective rank is necessary for solving inverse boundary value problem with the use of the singular value decomposition. The discrepancy principle that evaluates the discrepancy in observation equations and requires inverse analysis only is successfully applied to the selection of the effective rank. The effect of the effective rank on the estimation is disscussed.

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The shock wave generated by a spark discharge in water was observed with holographic interferometry. Double-exposure interferogram of the shock front was recorded by the use of AOM from CW Ar ion laser. A shock speed of 1495m/s was obtained from the recorded interferogram, and yields 9MPa of the shock front pressure.

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This resaerch aims at developing a mechanical artificial eyeball which realizes functions and mechanisms of the human eyeball, especially lens. The process of development must bring not only make usual optics devices smaller and higher powered but also understand a mechanism of human vision. The first step is developing a Far-close control device which changes focus distance by changing thickness of elastic lens. This paper reports analysis of the human eyeball to put a Far-close contorol device into practice and a model of the lens by FEM (finite element methd) and some results of simulation. As result, we show the feasibility of a Far-close contorol device.

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This paper is concerned with considering a decentralized optimal control strategy of traffic signals with regard to the maximum flow capacity for multiple intersectios. According to the performance of the optimal control strategy compared with one of a fixed-type signal control strategy, the optimal strategy is proved to be the more effective under several computational examples.

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We experimentally examined the floor vibration of a car body mock-up with the seated passenger in order to investigate the effect of the human body on the vibration response. As a result, we found that the acceleration peak level of the floor was decreased with increasing the number of the passenger, but the natural frequency of the floor was not changed. Furthermore, we calculated the vibration response of the mock-up with persons which modeled by using a mass, spring and damper. And we found that the calculated results were good agreement with measured.

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Recently, super-finishing stones with super-abrasive grain widely would be used. So this paper describes abrasive grain falling Mechanism of the super-finishing CBN stones. The relationship between cutting force and abrasive grain falling under super-finishing processing was investigated. Considering crossing angle in the crossing cutting, the force which charged on an abrasive grain was investigated by the crossing model test. Then, by the phase difference considering the stone width the relationship between abrasive grain loci and abrasive grain falling of the stone edge was examined. As a result, the main force caused the abrasive grain falling in 0.6N per mm^2. And, abrasive grain loci by the stone edge affect the grain falling and it is possible to be prevented the grain falling by average of crossing angle and contact area value on main force direction.

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