In order to reduce the weight of the automotive trim, instead of the resin material, the porous material has been used. In addition, most of the automotive trim is designed with multilayer porous media. In this research, in order to predict the sound insulation properties of the multilayer porous media, and use the SEA (statistical energy analysis) to create a SEA model to simulate the experimental device. The SEA model that we created, adding porous media of three layers using felt and film, to determine the amount of sound insulation analyzed. Finally, we describe the results compared with the actually measured sound insulation.

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To reduce the interior noise of the cars in high frequency region, the sound proof materials are laminated with the body panels and the interior trims. Therefore, the sound proof properties of the laminates play an important role for the efficient acoustical design. A program code which predict both sound absorption properties and sound insulation properties of the laminates are developed. This program code is used for transfer matrix method by Biot theory for Allard. This report described the outline of this program code, and the calculation results almost agreed with the experimental results.

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Vibration and acoustic analysis is applied to acoustic guitar to clarify its sound characteristics in consideration of transient sound after picking string. When a target transient sound is given, a new method to realize the sound is proposed by modifying the structure of guitar.

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A stationary grasping posture is classified in the control method of an electromyogram prosthetic hand. This grasping posture is static, such as an open hand posture, and one in which the operator of an electromyogram prosthetic hand intentionally continues muscular contraction. In operating prosthetic hand, because an operation image of prosthetic hand is different from the image of normal hand, an operator feels unnaturally. In this paper, authors propose a method that predicts a grasping posture using the surface electromyogram in hand preshaping and physical quantity sensors to solve the problem. Experimental results demonstrate that operators be able to control the prosthetic hand using proposal method more naturally than using conventional method.

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In this study, We have studied the effect of measurement posture on CAVI. Subjects are healthy adult males of 20-60 generations of 25 people. Measurement postures are supine, sitting and standing. As for the siting posture, by changing the reclining angle and knee joint angle, we also evaluate the effect of these on the CAVI. Knee joint angle are 0° and 90°. Reclining angle are 40°. Finally, by establishing a method of measuring in a sitting position, it will be applied to health care chair.

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In some subjects, it was found that the long-period oscillation of about 4 seconds cycle occurs in the ankle cuff pressure in the sitting position. This phenomenon is thought to be due to the release and stasis of artery blood flow in the femur. So, we investigated the influences of knee flexion angle on artery blood flow velocity and ankle cuff pressure at the lower limb.

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Today, physical strain on caregiver is a concern in a care facility. Specifically transferring from a bed to a wheelchair is hard work and causes a backache. Therefore, easy-to-use transferring devices are being developed in recent years. In our laboratory we have studied these devices which can pick person up and developed some prototypes. However, because these devices are leaned against with breast and knee, there are some problems. The first one is that users feel pain because of high pressure in chest. The second one is that they feel uneasy because the devices don't hold their back. In our study, we developed a new transferring device which can hold person's back and judged the performance of it in order to solve these problems. I designed a non-powered multi-link flexible arm system. These improvements will make stable transferring and enhance a sense of ease.

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Nowadays, aging is a serious problem in Japan. The evaluation of physical function for an elderly person and patients with hemiplegia is mainly carried out by a physiotherapist, so there will be an increase in the burden of physiotherapists in prospect in the near future. We want to estimate physical ability easily without resorting to physiotherapists, so we focused on handrails. We compare the rate of weight bearing on the hemiparetic limb which is used as an indicator of the ability to walk and the data obtained from handrail and the force plate became possible measurement of the load of the three axes by the strain gauge, so we seek walking ability from the data obtained from handrail and the force plate.

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When the elderly will not use the muscle, risk of requiring long-term care will be higher, hi order to prevent it, daily exercise is very important before occurrence of disability, hi this study, we focus on the walking being the most basic exercise, hi order to continue walking even if physical strength is reduced, we advance the development of assist device. Therefore we use shoes type sensor that can be attached easily. First, as the first step, we create the shoes type sensor and study how to detect the fall and prevent it in advance through experiments using the students.

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The serrated type of chip is formed by the occurrence of the localization of the plastic shear deformation, hi order to simulate the serrated type of chip formation, this study has considered Lemaitre's damage model. In Lemaitre model, there is only one parameter to control the damage rate. The damage rate will have a correlation with a value of the ductile fracture strain that is affected by both the stress triaxiality and Lode angle. Hence, this study considered the dependence of the stress triaxiality and Lode angle on the parameter. The numerical experiments were conducted by assuming three kinds of model for the parameter. A model that considers the effect of the reduction of the damage under high temperature and high compression as well as the effect of the stress triaxiality and Lode angle obtained appropriate chip formation.

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This paper describes the lapping and the sub polishing of the pure titanium which added the sodium oleate to the abrasives. By changing the addition density of sodium oleate, the abrasives and the polishing tool, the processing efficiency test of the pure titanium was done. As a result, in the lapping using 11.5μm silicon carbide powder, it became the biggest processing efficiency with 0.75% of the addition density. In the sub polishing using 3.0μm alumina powder, the processing efficiency improved with 0.01% of the addition density, and the surface roughness became 0.05μm from 0.1μm by the processing of 90 minutes.

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The large deformation that occurs while the turbine blades of forged material are machined, with another generation of the chatter vibration, are anembarrassing problem for turbine blades manufacturer like us, and what is more, appropriate information on this field is few. Then we decided to look for the solution experimentally considering such a current state. In the experiment, the influence level was examined about various factors on the cutting resistance. As one of the results, it has been understood that the number of cutting teeth of the tool greatly influences the machining accuracy.

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The large deformation that occurs at machining the turbine blades made of forged materials are an embarrassing problem for us, turbine blades manufacturer, with another problem such as the generation of chatter vibration. A lot of 12Cr steels are come to be used as the heat-resistant material for the turbine blades and, though the element improvements seem to be performed and to have improved their creep strength and so on, the characteristics on the machining, much more, the amount of the transformation at the machining are not considered at all. Then, an experimental research was done about some basic matters likes the tensile strength and the thickness of work-affected layer that are thought to be a cause of the transformation at the machining. As one of the results, it was understood that 12Cr steels didn't show the yield point and the difference in the diagram between before and after heat-treatment.

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This study incorporates a ring for compacting into a die by using the alumina granules were compacted five stepped cylinder using a lamination method. By incorporating the ring, it was possible from a die to obtain compact of plurality of shapes. However, high compacting pressure would be more affected spring back, so the ring destroy compact after pressing. Therefore, to improve the appearance by performing the compacted at a low pressure, reduced density supplemented by the addition of liquid paraffin is a lubricant. Brought about by changes in the compacting pressure and Liquid Paraffin added amount by examining the effect on the density and appearance were evaluated.

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Granule of alumina have been used as industrial ceramics. In this study, to make the green compact by pressurizing granule of alumina. Shape of the green compact is a square hole cylindrical shape. Compacting using a powder metallurgy process. Lubricant is added to alumina in order to compacting. Lubricant to be added is liquid paraffin. The amount of liquid paraffin to be added, 0, 2.5, 5.0, 7.5, 10.0 mass%. Compacting pressure is 75, 100, 125MPa. The study is carried out in these conditions. The purpose of the study is to evaluate the density change. Future challenge is to sinter the green compact. And is to evaluate the density and dimensional accuracy.

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In this study, the effect of material inhomogeneity on micro deep drawability for metal foils with thickness of 20μm is investigated by establishing FE model considering material inhomogeneity. As a result of FE analyses with homogeneous and inhomogeneous models, the limiting drawing ratio (LDR) is lowered with increasing grain size. It is because of microscopic inhomogeneous deformation and then the occurrence of wrinkle and strain localization. Furthermore, LDR is also lowered with increasing the standard deviation of inhomogeneous parameter. It is because of the evolution of localized deformation owing to surface roughening.

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For casting small polymer parts (10 mm cube), with the aim to achieve footprint-saving, simple operation, energy conservation, the realization of a small-desktop injection molding machine. To produce the machine which is an improvement to the new system disk from the conventional method of screw plasticizing process, its performance was evaluated injection. By modifying the compound charging angle, the hopper material, the rotor shape and the stator mechanism, proper running condition was successful compression molding. It was able to automatically and continuously extruding. As a result of ejecting polymer, a possibility of realizing a small-desktop disk-type injection molding machine was obtained.

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We make a prototype of the composite plating films for die of injection molding with excellent properties of mold release and die life. The plating films whose matrix are Ni-P electro-less plating are examined and evaluated by experiments of friction tests of plating film, measurement of mold release resistance at ejecting plastic molding from die, and surface roughness of plastic molding. As the results, the mold release resistance is large in order PTFE film, PTFE and Silicone resin film, BN and MoS_2 film, hard chromium film, this order almost agree with the results of frictional co-efficiency of their films. The surface roughness of plastic moldings is not affected by frictional co-efficiency of the plating film.

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The purpose of this study is to verify the advantage of lower frictional plating film on the die of injection molding. From the point of die damages and accuracy of plastic moldings, the molding experiments and finite element analysis are conducted. As the results, the plastic moldings are locally deformed at bottom and center due to cooling shrink and mold release, so that the surface of die is suffered the compressive stress by local contact, and the equivalent stress is increased on the contact area. However, the equivalent stress is able to decrease by lower frictional co-efficiency of die surface with using lower frictional plating film. It is possible that the damage of die is restrained and the plastic moldings are lower distorted.

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Effects of surface profile smoothing in laser multi-pass dieless drawing process are studied experimentally to fabricate microtube of stainless steel. In the experiment, material is SUS304 tube with outer diameter of φ500μm and thickness of 130μm. To investigate the effects of surface profile smoothing, drawing limit and distribution of outer diameter in each pass are measured. As a result, it is found that drawing limit increases by surface profile smoothing, and variation of outer diameter increases as the number of drawing increases. Consequently, it is found that removing the variation of outer diameter reduces the risk of fracture in multi-pass dieless drawing process.

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Recently, Stamping of a high precision parts is becoming possible by the spread of Servo-press machines. However, unsatisfactory results are sometimes found due to the loss of enough contact between dies and panels caused by die deformation or stamping stroke change. To improve productivity of servo-pressing, detecting the location of unsatisfactory contacts and knowing contact pressure there is important. We used the ultrasonic as a measurement method which doesn't involve processing of dies. We developed an ultrasonic propagation analysis program using FDTD(Finite-difference time-domain), and the contact state was visualized.

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Machining accuracy of machine tools relies on accuracy of the relative motions between workpiece and cutting tool. In case of the ultra-precision cutting, depth of cut is several micrometers. In addition, if the machining of high hardness materials is carried out, ratio of the cutting thrust force becomes large. Therefore, high thrust stiffness is necessary for the machine tool in particular. This study designed the spindle for ultra-precision machine tools. The designed spindle achieves high stiffness with the water hydrostatic bearings. In addition, it is expected that the higher bearing stiffness reduces dimensional error of machined workpiece. For preventing surface damage of the spindle parts, DLC coating is applied on a spindle rotor and inner surfaces of the casing. This paper presents feature and calculated performances of designed spindle.

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The spindle is a vital component of machine tools. In particular, the ultra-precision machine tool equips the precision spindle system, hi general, the precision spindle uses hydrostatic bearings for achieving precise rotational motion. An important performance index of the hydrostatic bearings is the bearing stiffness. In many design cases of the hydrostatic bearings, however, actual bearing stiffness of the fabricated bearings becomes smaller than that of design. Our previous reports indicate that the pressure of the lubricant fluid deforms the parts of the spindle that changes critical dimension of the bearings such as bearing gap. This report thus investigates the influence of the fluid pressure on the bearing stiffness. In particular, the paper considers the influence of the deformation on the stiffness when the spindle rotor moves due to the external loads. The FEM analysis and numerical calculation reveal that the influence of deformation reduces the bearing stiffness by about 10%.

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The fiber laser joining between non-alkali glass sheets was conducted using vanadium-based low melting-point (m. p.) glass frit as an insert material, hi order to investigate the reason of blowhole formation in glass frit during laser irradiation, high-speed camera observation was carried out. As a result, it was found that the most of blowholes were derived from inherent voids contained in/on glass frit. For the suppression of blowhole formation, the thermal treatment of as-received glass frit in air/vacuum atmosphere was proposed. In the case of heat-treatment in vacuum atmosphere, the joint quality was improved because the contained voids in glass frit was surface-exposed before laser irradiation.

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The crack propagation behavior was observed by high-speed camera during wheel scribing of non-alkali glass sheet. As a result, it was found that the propagation depth was largely influenced by the applied load to scribing wheel. In the case of glass sheet of 0.7 mm thickness, for example, a formed crack rapidly propagated to the depth direction when the applied load was 20 N. On the other hand, when the applied load was 10 N, a formed crack hardly propagated. In order to investigate the reason of difference between crack propagation behaviors, high-speed birefringence measurements were also conducted. The measurement from above of glass sheet showed that the characteristic patterns appeared in phase difference diagram depending on the applied load conditions.

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A mass-micro spring vibration system was constructed and its damping characteristics were studied experimentally. When some systems are miniaturized, its dynamic characteristics such as damping cannot be estimated, because miniaturizing a machine makes the influence of gravity weaken and several effects such as static electricity or friction force may become strong compared with inertia force. In this study, a mass-micro spring system, which is considered as the most basic dynamical system, was constructed and its damping factors were examined. For the first experiment, the influence of airflow damping was evaluated. Consequently, even if the system size was as small as in this study, it was smallest compared with other factors. And for the second experiment, the influence of material damping was estimated. But the relation between spring volume and material damping could not be understood.

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This study proposes a sensitivity analysis for improvement of transient response of time history data. For improvement of vibration characteristics of structures, it is necessary to find the appropriate location for the structural modification. However, it is difficult to apply sensitivity analysis to time history data since the sensitivity analysis has been conducted only in the frequency domain. This study presents a sensitivity analysis for the transient response of time history data. As an example, the proposed method is applied to a construction equipment in order to reduce a peak of vibration response in the time domain.

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Frictional vibration occurred in a dynamic system composed of a belt and a slider supported by springs was simulated by Cellular Automata. Cellular Automata is a discrete modeling system of complex phenomena, in which time transition of state variables is simulated at each tune step just by local neighbor rules introduced to make the relation of state variables to each other on neighboring cells. The friction dynamics has been studied for a long time and various modeling technique have been proposed, but dynamical behavior on friction surface has not been revealed yet. This may be caused by the complexity of behavior on that surface. In such cases, Cellular Automata may be applied as a strong tool of modeling because we need not derive the governing equation in the procedure of Cellular Automata. In this study, we succeeded in modeling the friction dynamics by introducing local dynamics of contact points between solid surfaces. Based on spring-block model proposed by Burridge and Knopoff, a new layer of internal surface and rules were introduced to consider the contact area of friction surfaces. Stick-slip and self-excited vibration dynamics could be modeled successfully by this new model.

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Response analysis of a nonlinear system subjected to combined Gaussian white noise and irregular impulse excitations is performed. The white noise and irregular impulse excitations are denned by using the statistical moments. The response characteristics are examined by changing the intensity ratio between the white noise and irregular impulse. To obtain the stationary probability density function of the response, the moment equations of the response and Gaussian sum approximation, which expresses the response distribution by the weighted sum of the several Gaussian probability density functions, are used. In the illustrative examples, the response distributions of a Duffing oscillator are compared with the results of the Monte Carlo simulations.

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Response characteristics of a single-degree-of-freedom linear system subjected to narrow-band non-Gaussian random excitation are investigated. The excitation is assumed to be a stationary stochastic process characterized by the non-Gaussian probability density and the narrow-band power spectrum. As the probability density of the excitation, bimodal distribution and Laplace distribution are used. Monte Carlo simulations are carried out to obtain the stationary response distributions. It is shown that the response distribution varies markedly depending on the bandwidth, dominant frequency and non-Gaussianity of the excitation. The response characteristics are discussed by using the cross-correlation coefficient between the excitation and the response.

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This paper describes tribology in micro-scale order that is influenced by low friction force caused by low normal load. Recently, micro machines have been used in various fields. Tribological property in micro-scale such as micro machines move is known to be different as compared to macro-scale tribology. The aim of this research is to clarify micro tribology and evaluate it. We selected diamond stylus tip and fullerene polymer thin film as specimens in this research. In this experiment, friction force between two specimens is measured by using scratch tester. Besides, we observed friction groove with SEM. In conclusion, some knowledge about micro tribology has clarified.

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In engineering fields, surface roughness parameters are widely used for mechanical designs. However, actual surfaces have many factors which we cannot express by using a single standard surface roughness parameter. We think that there is needed to develop a geometry parameter which is applied to all surface conditions and to characterize tribological properties based on an ideal surface whose roughness parameters are completely controlled. In this study, effects of grooves on the surface roughness parameters and the tribological properties were investigated. The grooves have various pitches, processed by ultra-precision cutting. A correlation between the change of the grooves on boundary lubrication and the standard surface roughness parameters are discussed.

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Friction is important in our life. However, frictions cause problems such as lowering of energy efficiency or shortening machine's life in the industrial field. Recently, many kinds of micro machine technologies have been developed continuously and tribological properties in micro scale order have become an important research area. However, there are still many tribological properties in micro scale order, which has not been revealed yet. The purpose of this study is to clarify a friction phenomena in micro scale order using diamond with the curvature radius of tip being 5[um], and synthetic silica wafer. It turned out as a result that frequency characteristics that the friction coefficient regarding distance change depending on normal load.

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Electronic devices with stretchability can be applied to various areas because stretchability enables bending and stretching while in use. Therefore, electronic devices consisting of stretchable electrodes enclosed in elastomer have been developed. We manufactured a prototype of a data glove as an application of the strain sensing line using GaInSn stretchable electrodes (GaInSn: low melting point eutectic alloy consisting of 68.5 % Gallium, 21.5 % Indium, and 10 % Tin) enclosed in PDMS sheets. In this paper, we demonstrated that the folding state of fingers could be identified. The proposed technology may allow for the creation of a lightweight master hand manipulator or three-dimensional data entry device.

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New type of strain sensor using a CMOS inverter oscillator circuit has been developed. This type sensor can omit an amplifier because a counting device measures frequency changes of circuit voltage output caused by resistance changes of a strain gauge. In this study, the authors manufactured one small prototype strain sensor using a CMOS inverter oscillator circuit. Characteristics and measurement accuracy of this small type sensor were confirmed through static tensile tests of specimens. The test results showed that the same level of accuracy as conventional sensor has been achieved by this small type sensor.

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Transfer Path Analysis (TPA) has been conducted in order to improve the noise and vibration quality of mechanical structures. However, the force identification in the TPA is still challenging problem and its accuracy has to be improved. The Matrix Inversion Method is an approach to force identification. The Matrix Inversion Method estimates the excitation force by the product of an inverse matrix of accelerance and a vector of actual operational acceleration. It is known that the Matrix Inversion Method is very sensitive to measurement noise especially at the resonance. This paper proposes a new force identification method by using strain measurement. The method estimated the force using the strain Frequency Response Function (SFRF) instead of acceleration. A vibration experiment is conducted to compare the results by the proposed method with the conventional method.

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Carbon fiber reinforced plastic (CFRP) possess high-specific strength and is applied to various member of structure. It has been clarified that delamination and deformation of fiber occurred on CFRP, a fiber composite and laminated material, from repeatedly applying of loads. However, strain distribution behavior that takes account of stress concentration zone such as groove and circular hole has not been clarified yet. In this research, we conduct cyclic load examination of torsional moment using digital image correlation method, and the residual strain distribution behavior of circular hole's surrounding of CFRP with circular hole was observed. As a result, we have clarified that the behavior of residual strain distribution relies on fiber orientation. Moreover, we also have clarified that the size of residual strain is affected by fiber orientation, with respect to the number of cycles of repeated load torsional moment.

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In the aircraft structure, the weight reduction is severely demanded and recently there exist many fastener joints between metal and composite parts. Therefore, it is important to investigate the mechanical behavior and evaluate the damage of bolt in composite/metal fastener joint. The authors proposed the smart bolt embedded optical fiber sensor as a monitoring instrument of the fastener joint. In the previous study, it was shown that the bolt fall in the multiple-row fastener joint can be detected by using the smart bolt, hi this study, FEM analyses for the multiple-row fastener joint of in-line array specimen were conducted assuming the looseness of a joining bolt. Based on the analytical results, it was shown that the bolt looseness around the smart bolt can be detected.

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The purpose of this study is to investigate the joint strength behavior of lead solder (Sn-37%Pb)/Cu and lead-free solder (SAC305)/Cu specimens by the tensile test. The effect of strain rate on mechanical properties and fracture mode was investigated. The joint strength of SAC305 was increased up to about 10^4μm/min of crosshead speed. And that of SAC305 at 10^5μm/min was suddenly decreased. On the other hand, the joint strength of Sn-37%Pb was increased monotonically. After these tensile tests, microstructure observations were conducted for solder joint's interface and fracture surfaces. The rupture behavior of SAC305 was changed around 10^4μm/min. That of Sn-37%Pb was unchanged in crosshead speed.

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The object of study is to evaluate crack growth in creep fatigue test. In this study, fatigue test and creep-fatigue test with relatively long hold time (30 minutes, 60 minutes, and 150 minutes) were conducted under strain-controlled. The specimen is perforated plate that made of SUS304 stainless steel. We measured crack length by using CCD video camera at a constant frequency and compared it with the expression of relations of crack propagation rate and J-integral given in a precedent study. It was found that strain hold time is longer in creep-fatigue test, crack propagation rate per cycle is faster. And the expression in a precedent study is effective in the SUS304 stainless steel.

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This study measured the crack growth in perforated plate of SUS304 stainless steel by a creep fatigue test as a clue to evaluate the creep fatigue characteristic that a structure member is under the elevated temperature. The crack generated by the test is taken by the CCD camera, each and life evaluation when changing the diameter of the circular hole, and was examined crack growth evaluation. From the measurement, as the diameter of the circular hole is small, early crack beginning point, the crack length damage hour tends to be long. In addition, number of repetitions of damage is less the larger the diameter of the circular hole. From Campbell diagram evaluation, by using the number of repetitions of crack initiation Nco.2 and Nco.4, for more than a Factor of 3 area, it is possible to evaluate in more safe side.

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Small Punch (SP) creep test has been recognized as a practical procedure to examine creep rupture lives only sampling a very small volume. However the standard testing method for the SP creep has not been established yet. In this study, SP creep tests in air and in vacuum were carried out at 600℃, employing 2.25Cr-1Mo Steel and using two types of loading balls which vary in a diameter of 2.0 mm and 2.38 mm. As a result, creep rupture lives with the loading ball of 2.38 mm in diameter were longer than these with that of 2.0 mm. On the other hand, there were little difference among the test results in lower applied load levels in air and in vacuum in the case with the smaller ball. Furthermore there were also little difference among the tests results regardless of the atmosphere, when the bigger ball were employed.

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Some destructive techniques are required to evaluate the degradation of components under elevated temperatures. However, conventional uniaxial creep specimens were sometimes too large to collect them from local area of target components. Miniature Creep (MC) test has been recognized as a semi-destructive technique to examine the damage condition of components. They employ small size specimens that can reduce the conventional uniaxial creep specimen in similarity. In this study, MC tests using round bar and thin plate specimens were performed in Argon gas to measure creep properties, and compared with uniaxial creep test results employing 2.25Cr-1Mo steel. It was shown that MC rupture lives were a similar trend those of uniaxial creep, and the MC test is able to substitute for conventional uniaxial creep test.

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The elasto-viscoplastic cons titutive equation based on the concept of continuum damage mechanics was formulated for the niobium alloy (C103) which was used as a thruster chamber material in a satellite. Creep fatigue life analysis based on damage mechanics was conducted to simulate the experimental data obtained by the stress con trolled creep fatigue tests using the specimens made of the niobium alloy. Lots of material parameters in the constitutive equation are determined based on the experimental data. Creep fatigue life was also evaluated and the validity of material parameters was illustrated by comparing calculated values with test results.

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This study investigated the effect of streamer discharge on combustion in a Spark Ignition (SI) engine. A continuous streamer discharge was generated in the spark plug of the combustion chamber of a 2-stroke optically accessible engine that allowed visualization of the entire bore area. The experimental results showed that ignition and combustion operation by using streamer discharge ignition alone is possible. In addition, we found that the flame formation and propagation was initiated and grew from the vicinity of the electrode under the application of a streamer discharge by visualization experiment. Additionally, the results indicated that raising discharge voltage increased the light emission intensity at 306.4 nm corresponding to the OH radical and advanced onset of initial flame.

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For high efficiency combustion, gasoline engine is adopted Direct-Injection method. However, there is problem that unburned ingredient is occurred by attaching injection fuel in a combustion chamber. Furthermore, up till now, many studies about stratified charge combustion by using multi-point ignition for improvement lean combustion. This study has been investigated that the effects of multi-point ignition on combustion characteristics in heterogeneous combustion field. The main conclusions are as follows; 1) In lean combustion field, the maximum burning pressure increases remarkably by using multi-point ignition. 2) At same overall equivalence ratio, the maximum burning pressure for multi-point ignition make a difference by changing of spark-plug position.

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In this study, the fire source model was investigated to predict the damage of electric cable in fire accident. The Polyethylene based Eco-Material (EM) cables and heat/fire resistant Non-Halogen (NH) cables which were used in nuclear power plants were applied to the flammability tests. The cone calorimeter tests for EM cables and NH cables were conducted to evaluate relationship between ignition time and heat release rate(HRR). Two fire source models, the HRR model and the chemical reaction model in CFD simulation code(FDS5.0) were applied to represent the flammability tests results of multiple cables.

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The latest automobile technological innovations are necessary to improve the lean combustion and remarkable reduce of emissions like CO_2, NO_x, CO. Focused technologies for improving combustion are the flame temperature and the turbulence flow control, for example lean burn and exhaust gas recirculation (EGR). However, the lean combustion has the points at issue, for instance, deteriorating in ignitionability, generating arrhythmic flame and increasing combustion time. This study has been carried out to improve the lean combustion behavior from the view point of the flame speed by using the combination flow. The main conclusions are as follows 1) The average flame speed with combined flow is bigger than that of laminar flow 2) The average flame speed with combination flow increases than that of combined flow at same equivalence ratio.

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In late years, the global environmental problems and the energy efficiency problems become very serious. It is well known that for automotive diesel engines, low-particulate and low-NOx emissions are very much needed by using alcohol blend fuels and emulsified hydrocarbon fuels. It is due to control the flame temperature caused by oxygen and calorific value in alcohol blend fuels. As the first step in this study, experiments have been carried out to determine the influence on fuel consumption rate and soot emissions for diesel engines by using the alcohol blended fuels.

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