In the past few decades, many micro-electromechanical systems (MEMS) devices have been developed. To encapsulate a tiny MEMS device into a microcavity, a sealing ring is often used. The sealing ring is fabricated on a cap wafer or on a MEMS substrate by Au electroplating. The electroplated Au surface is rough compared to polished wafer surface. Therefore, high temperature bonding process is often used in order to deform the Au and achieve intimate contact. However, it is expected that Au surface with much smaller roughness can form intimate contact at lower temperatures. In this work, we carried out the room temperature bonding using electroplated Au seal rings smoothed by two different methods. One is a surface smoothing by thermal imprint method using smooth substrate as a master mold. Other is a surface smoothing by lift-off method using a sacrificial layer. Moreover, hermeticity of bonding processes using these smoothed surfaces was evaluated by diaphragm structures, which were prepared by photolithography and dry etching of Silicon-On-Insulator (SOI) substrate. As a result, good hermetic sealing was confirmed using the replicated surface smoothed by lift-off process.

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In the recent years, a number of papers on electric discharge machining, electrochemical machining, and fine particle jet machining have been reported. Applying these micro scale machining methods to the nano scale machining compatible with semiconductor processes as in MEMS faces several difficulties. In this paper, nano particles were applied in order to establish a new nano scale machining method by imprinting the shape and diameter of nano particles through plasma generated in air. As the first step of this study, the relation between the shape and diameter of nano particles and the surface feature of workpiece caused by plasma discharge in air was focused.

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We demonstrates ZnO thin film deposition by using supercritical fluid chemical deposition and the application of the ZnO films in improving the adhesion of Cu/glass stacks. Zn-MOPD (Zn(C_9H_<15>O_3)_2) was used as a precursor, and the deposition was carried out at different O contents and temperatures. When O content was higher and/or deposition temperature was higher, white polycrystalline ZnO films were formed on a glass substrate. Brown ZnO films were deposited when O content was lower and/or deposition temperature was lower. XPS analyses indicates that the white ZnO films had less C contamination. A significant improvement in the adhesion of the Cu/glass stacks was observed when the fabricated ZnO film was inserted between Cu and glass.

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In the study of copper corrosion, a microfluidic device was used to provide an experimentally controlled environment of flux and atmosphere. Copper layer formed by the sputtering method reacted with gas controlled water which was four kinds of concentration of oxygen and carbon dioxide each high and low. Linear flow velocities (LV) above the copper layer were 30, 50 and 70 cm/s, and the flow time for all experiments was 120 min. After each flow tests, the copper layer surface was observed using SEM, while the roughness was measured using AFM. In the case of LV 50 cm/s, copper layer was most corroded in the case of oxygen and carbon dioxide both high, and secondly corroded in the case of only oxygen high. The case of only carbon dioxide high and the case of both gas low were slightly corroded and were not very different from before test. These results were thought to reflect a two-step reaction of copper oxidation and dissolution.

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In chemical mechanical polishing, polishing proceeds through chemical and mechanical action in the fine gap that exists between the wafer and polishing pad. Therefore, clarification of the polishing mechanism has been delayed. Various researchers have pursued the clarification of the polishing mechanism. Although the slurry flow in a microscopic pad asperity is thought to play a critical role in the transport of abrasive particles to the wafer surface, this has not been completely elucidated. In this study, we devised a visualization method for the slurry flow in the pad asperity area. Because in situ observation of the slurry flow at the asperity scale between the wafer and polishing pad is extremely difficult, we visualized the slurry flow according to the scaling law of the flow using the visualization model of the enlarged pad asperity. The results showed that we were able to visualize the flow imitating the slurry flow in the fine gap between the wafer and polishing pad.

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In the CMP (Chemical Mechanical Polishing) process, the polishing pad is a factor which greatly affects the polishing performance, since the surface shape of contributing to the polishing pad has a very fine and complex shape, the analysis of polishing pad surface is difficult. We have analyzed the polishing pad surface shape by using the method of optical Fourier transform was devised on the basis of the diffraction phenomenon of light. In this study, by altering the incident angle of the laser beam to be irradiated to the polishing pad, we report makes it possible to clarify the difference of the polishing pad surface shape.

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In order to gain insight into the mechanisms of polyvinyl acetal (PVA) roller brush cleaning in semiconductor device fabrication, we measure the friction force between two types of roller brushes and several surfaces to evaluate the influence of surface wettability. In addition, contact and water behavior between nodule and surface was observed by high-speed video camera. When the roller brush with four rows nodule scrubs on large contact angle surface, the friction force also shows large value. In addition, the time series of friction force of single nodule also shows the different force curve depending on the surface wettability. High-speed photography indicates that the amount of water seeped out of nodule depends on the surface wettability. We believe that the water behavior during the nodule contacts play an important role for the PVA brush friction.

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To reveal the mechanism of watermark formation on a Cu film, the Volta potential in a droplet area on Cu was evaluated using the scanning Kelvin-probe method. The droplet area on Cu exhibited an upward convex potential profile, indicating that the electrochemical reactions were more active in the areas around the droplet than at the center of the droplet. On the other hand, Si exhibited a profile converse to that of Cu: electrochemical reactions were more active at the center of the droplet area than in the areas around it. These evaluations revealed that the pinning and ring-shaped watermark formation at the droplet area on a Cu film resulted from the said Volta potential profile.

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Droplet behavior on a rotating disk was experimentally investigated. The experiments were carried out using hydrophilic (Type A) hydrophobia (Type B) and wafers as the test disk. The droplet movement and breakup upon rotation wafers were observed using a high-speed video camera. As a result, the droplet on the Type A was found to remain on the moving part, without breaking up into droplets. On the other hand, the droplet on the Type B was found to elongate and then breaking up into smaller droplets due to the centrifugal force. Furthermore, it was confirmed that the droplet behavior was greatly influenced by the film type rather than the contact angle.

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Characteristics of droplet removal by air flow on flat surface of semiconductor wafer were experimentally investigated. Effects of air velocity, nozzle angle and droplet volume on removal characteristics were measured. Deformation and removal processes were observed using a high speed video camera. Type A and Type B wafers were used as the test plate in order to investigate the contact angle effect. It was confirmed that the removal condition was shifted to the lower air velocity with increasing of droplet volume.

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The droplet evaporation process was categorized into two types, i.e. constant contact radius (CCR) and constant contact angle (CCA) types. The present study was aimed to construct the mathematical model to describe the droplet evaporation phenomena for CCR and CCA types. The mathematical model was developed by considering evaporation phenomena at the droplet edge. The change of droplet volumes predicted by the mathematical model were compared with the experimental data of droplet evaporation of Cu, Low-k, and Th-Ox wafers. As a result, it was confirmed that the result of developed model was in agreement with the experimental data.

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Characteristics of liquid jet cleaning for a rotating semiconductor wafer were experimentally investigated. Flow patterns on the rotating wafer were visualized using a high speed camera. Hydrophobic and hydrophilic wafers were used as the test wafer for the investigation of contact angle effect. White pigment was mixed with the water for visualization. Visualized images were binarized for the analysis of flow pattern, hi order to measure the particle removal by the liquid flow from the wafer surface, optical measurement system was developed using the phosphorescence particles. As a result, it was confirmed that the flow pattern was strongly affected by the surface affinity of semiconductor wafer.

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Graphene-like two-dimensional layered materials such as transition metal dichalcogenides are prospective as nanoelectronic and nanophotonic materials. Among transition metal dichalcogenides, molybdenum disulfide MoS_2 is especially attractive because they are direct bandgap semiconductors; in addition to MoS_2, molybdenum diselenides MoSe_2 and molybdenum ditellurides MoTe_2 are also worthy of attention. In this report, the electronic band structures of these three dichalcogenides under strains are obtained by means of first-principles calculation. The imposed strain is either uniaxial or biaxial. It is revealed the bandgaps of these dichalcogenides are direct in the finite range of strain, while they are indirect in the lower and upper ranges. The maximum bandgaps appear at the lowest strain in the range of the direct bandgaps.

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The demand of high-speed and efficient cell separation techniques has increased with the increased interest in regenerative medicine. Conventional methods of cells separation are not so efficient due to the ID operation and high load toward cells. In this paper, the possibility of peculiar cell separation with dielectrophoretic (DEP) force is studied and discussed. The opposite DEP forces for living and dead yeast cells are found at the applied frequency near 4MHz. Moreover, the DEP force simulations is performed based on the complex dielectric constant obtained from experiments. From the simulation result, separation rate of living cells and dead cells are predicted to be 65% and 90%, respectively. Finally, we concluded that it is possible to separate peculiar cells with DEP force.

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The objective of this work is twofold in terms of the electronic applications of the slime mold. One is to give electric conductivity. To do this, we tried to "inject" metal particles. In order to keep alive the slime mold, Ag nanoparticles were mixed in a feed, and were fed to the slime mold. STEM-EDX analysis revealed that the accumulation and agglomeration of Ag nanoparticles. When much larger particles were mixed, those particles aligned along the branches of the slime mold. Another subject is to control the external profile of the slime mold. The slime mold is usually cultivated on an agar media. We cultivated the slime mold on a glass plate having scaffolds. Obviously the slime mold traces the scaffold.

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A manipulation of cells is important technique to improve medical technology for cell transplantation and regenerative medicine. Controlling particle migration and flow with a micro sharp electrode using alternating current(AC) electric filed has several potential to develop cell manipulation device. This device is useful for the cell manipulation and it is easy to control cells with their dielectric properties. In this study, a confirmation of the shape tip electrode for the cell manipulation under AC electric field was introduced and the cells and particles velocity near the electrode tip under several conductivity conditions were measured to investigate the flow structure around the electrode with the particle image velocimetry (PIV) method.

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Carbon nanotubes (CNTs) encapsulating organic molecules attract much attention of researchers nowadays because of their optical properties; they are applicable to nanophotonic devices. In this report, the formation of CNTs encapsulating coronene molecules is investigated. Firstly, the statically stable structures of CNTs encapsulating coronene molecules are seeked with the help of conjugate gradient energy minimization. Next, the dynamical process of the encapsulation is examined by means of molecular-dynamics simulation. It is revealed the tilt angle of the stacked coronene molecules depends on the radius of CNTs and temperature.

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Optimum design of energy storage is a keen issue on the stand-alone energy system using renewable energy. However, the previous design method does not always give us satisfactory performance of the system. This is because the variations of the daily power generation and consumption caused by the weather condition are not taken into consideration. In this study, we have introduced a random variable, which takes into account the daily variations in capacity design. The present stand-alone energy system consists of the power storage device and the solar cells. We discuss on a technique for obtaining a probabilistic relationship between the performance of the system and the capacity of the power storage device.

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The necessity for the development of micro power supply technologies for mobile phones and portable electronics has increased in recent years. Methods of self power generation using the vibration loads of structures have received attention. In this study, we focused on lead zirconate titanate (Pb(Zr,Ti)O_3, PZT) as the generating piezoelectric element. The purpose of the study was to develop a high-efficiency PZT generator element that utilizes the vibration loads in the support members of a structure. We have reported the power generation characteristics of laminated PZT elements under vibration loads. We evaluate the power generation of laminated PZT elements and present the results of an experiment using a switching circuit as a load circuit in order to confirm the suitability of the laminated PZT element as a power source.

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Recently, various systems that use hot spring and industrial waste heat of comparatively low temperature area have been proposed. There is a binary cycle power generation system that generate power using conventional Rankine cycle that get energy from heat carrier and organic medium (HFC-245fa, pentane) with low boiling point. This paper describes feasibility study on installing the binary cycle power generation and the ground source heat pump systems into the hot spring facilities and agricultural farm in Yamanashi Prefecture. We will utilize exhaust gas from biomass gasification power generation system on introducing binary cycle power generation system to the farm. As a result of this study, it is possible to install both system of the binary cycle power generation and the ground source heat pump system as combined heat utilization system.

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The purpose of this study is to investigate a heat exchanging performance of a ground source heat pump using direct expansion method. The direct expansion method for heat exchange wall be more efficient comparing with the conventional indirect heat exchange method. However difference to the conventional indirect heat exchange method calorimetric measurement in primary side is difficult. And so it measured the calorimetric in secondary side and performance of a ground source heat pump evaluated. Also about air flow measuring of the calorimetric in secondary side consider measuring method and to improve the accuracy in the measurement.

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Impressions of freshmen in "College of Technology'' on welding practices and simple manufacturing and then reactions of parents who read their impressions are introduced. It is found that they grow up by practices.

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In our laboratory, manufacture and flight tests of PET bottle rocket and flow visualization around water rocket model in the first semester of 2nd grade have been carrying out as introductive education of fluid engineering. The objective of this paper is to enable the students in the first semester of 2nd grade to understand a stall phenomenon arising in the water rocket at the optimum launching angle, which is calculated by a computer. The separated line around the water rocket at the attack angles of 0 to 45 degree have been visualized by using a phenolphthalein method in an experimental apparatus of an improved water tunnel.

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This paper describes a new concept of children engineers coaching school. We suggest the engineer training education that has not been practiced in primary education in Japan. Under this condition, already a large number of scientific classrooms have been held in various places. Knowledge teaching of scientific phenomenon can be used as experience education, to achieve the engineering development education not performed in school education. As a result, engineer education with a wider experience is expected. After this education, student will enter university science and engineering division, and will be employed in Japanese company. Thus educated engineers, it is expected to be a big success in worldwide, such as planning of new products.

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The understanding about mechanical principles and structures are very important for students of the teacher-training course of technique. The Students of this course learned how to use the 3D CAD. Students have created a simple parts using it. Furthermore, by using these parts, students assembled a single device. In the next task, students, created a parts that make up the strandbeest mechanism, and assembled them. Through these tasks, students learned about the mechanical structure and its dexterity. This report introduces this new trial of teacher-training course of the technique of Kanagawa Institute of Technology.

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An area-type shear difference method was used to analyze stresses using data (principal stress differences and principal stress directions) obtained from photoelastic experiment. The method used an approximate equation of a directly integrated stress-equation of equilibrium between two points (nodes) in any direction. The method was applied to a circular disk subjected to diametral compression and the effect of the length between nodes on the stress components of the disk was investigated. Results indicated that the stress components obtained by the method were affected by the length between nodes.

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The photoelastic sensitivities of ultraviolet (UV)-curable resins irradiated to UV radiation for different times were measured using a photoelastic technique. The liquid UV-curable resins poured in the pocket (55 mm long, 5 mm wide and 3 mm thick) of an acrylic mold were irradiated to UV radiation for 45 s to 960 s. The specimens (50 mm long, 5 mm wide and 3 mm thick) were cut from the resins irradiated for different times. The specimens placed in a circular polariscope were subjected to four-point bending using a universal test machine. The photoelastic sensitivity for each specimen was determined through the use of the relationship between the orders of isochromatic fringes appearing at the upper and lower edges of the specimen as the bending load increased and the loads at which their fringes appeared during the bending test. The photoelastic sensitivities were approximately constant regardless of UV radiation time.

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There are many problems in the fatigue cracks for the expressway since the high economic growth period. These damaged parts have been increasing tendency every year recently. We consider that the budget can be reduced by planning to repair for strategy forecasting the crack growth. However, when the fatigue cracks happened the high cycle fatigue cannot be endured using strain gauges. To overcome this problem, the piezo-electric material with high mechanical strength is used by measuring as strain gauges. The comparison examines whether to relate the timing that becomes unstable destruction from the stability destruction. The strain gauges and the piezo-electric material generated the voltage measure the strains around the cracks. We produce the crack growth by the liberating energy method.

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Many social infrastructures and buildings are built with concrete as an eternal structure. When the materials are used by woods, these materials have enough strength and proof stresses under enough environment. In addition, we may contribute to local production for local consumption. Also there are advantages that the environmental conservation and the regional activation can expect. The building materials are susceptible on the local climatic condition and the wood particular service lifes are changed by temperature and the humidity. Therefore, we record a change by aging about strength of the wood as materials in this study and observe it about erosion of the corrosion. Furthermore, we analyze how woods change using the correspondence principle applied by a viscoelastic idea.

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This study proposed 3-dimensional homogenized finite element analysis of polymer foam. The effect of microstructure on macroscopic mechanical behavior was evaluated by using this code. The hyperelasticity was applied to the simulation code to consider non-linear mechanical characteristics of matrix of polymer foam. A part of the microstructure was applied to the unit cell for homogenization method, and it was under the periodic boundary condition. The unit cell was supposed to have either spherical or cubical void (called cell) in the center of the unit cell. The calculated stress-strain curve showed good agreement with the experimental results. As a result of comparison between spherical-cell model and cubical-cell model, considering cell shape was found to be important in improving the accuracy of calculating mechanical characteristics of polymer foam.

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In this study, a homogenization analysis of polyurethane foam to consider the microstructure was conducted. Polyurethane foam test specimens, relative densities of which were 0.21g/cm^3, 0.27g/cm^3, 0.37g/cm^3, were applied to the uniaxial compression tests. An original 2-dimensional simulation program was developed. A polyurethane foam was defined as a material which has a periodical microstructure. The simulation model had periodic and two lands of sized pores. The applicability of the proposed model for polyurethane foam was shown by comparing the analysis results with the uniaxial compression test results.

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The tensile deformation behavior of polyvinylidenedifluoride (PVDF) hollow fiber membranes used for water purification is studied. The present PVDF membrane has sub-micron pores with open cell structure. The surface and cross section of the membranes is observed by FE-SEM to investigate the microstructure (cell size and geometry of the cell ligament). During uni-axial tensile test, the membranes underwent elastic deformation and plastic deformation. In order to establish the mechanical model for such a tensile deformation, finite element model (FEM) is carried out. In this model, Kelvin polyhedron (truncated octahedron) was employed to create 3D open cell structure. Such one-unit cell approach can predict elastic deformation and then it is concluded that we establish a fundamental FEM model to describe the deformation behavior of porous structure. The present model enables the prediction of the macroscopic deformation behavior of the membrane, by taking into account of pore structure. The insight may be useful for porous membrane fabrication and for reliable operation of water purification.

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This study investigated compressive deformation behavior of low-density porous polymer materials. The present polymer material has micron-size pores with closed cell structure. The porosity is about 94 %. Uni-axial compressive test was first carried out. It is found that the stress - strain curve indicates a plateau region, when the material undergoes plastic deformation. Next, finite element method (FEM) was carried out to simulate the deformation behavior of the material. In the FEM model, the yield criterion which considers both Mises stress and hydrostatic stress component was employed, since the hydrostatic stress is crucial for the effect of porous structure on the macroscopic deformation. Indeed, this continuum plasticity framework was proposed by Deshpande and Fleck, suggesting that it is applicable for metallic and polymer foams. By using the present FEM and experimental data, we established the computational model for plastic deformation behavior. To verify our FEM model, several indentation tests with different indenters (spherical indentation and wedge indentation) were carried out in order to generate various tri-axial stress states. From the series of experiments and computations, we observed good agreement between the experimental indentation curves and the computational ones. Therefore, the present FEM model can predict the plastic deformation behavior subjected to uni-axial compression and indentation loadings.

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In recent years, there were big earthquakes such as the Great Hanshin-Awaji Earthquake and the Great East Japan Earthquake therefore, the evaluation of seismic and safety of the structure has been demanded for unexpected damage. In this research, we measured the displacement of the CLT (Closs Laminated Timber) panels which were suffered the shear loading by using the digital image correlation method. Many target sheets were attached on the measured wooden CLT panels. The partial images of the target marker were traced with the pattern matching of the image correlation method. The strain distribution was calculated for the triangular elements consisted of three targets located near.

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The image correlation method is used for the displacement and strain measurement of the structures. The image correlation method is a method in pursuit of partial image using pattern matching. In this research, we propose a new image correlation method to improve the accuracy of sub-pixel estimation at the positioning of target image. The proposed method, which combines the curve fitting and image interpolation, can obtain the subpixel position precisely. The goal of this research is to achieve the measurement precision of 1/100 pixel.

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A luminous marker or a reflection marker is used in motion capture and the two or three-dimensional image measurement as a target. When a luminescent marker is composed with LED, it is made with several LEDs because a luminous point of the LED is small. In this research, the influence of the size of the LED marker and the state of the lens focus on the measurement precision was investigated. It was found that the displacement of the luminescent marker could be measured by the resolving power of the subpixel even if in condition of some unfocused state.

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Digital image correlation method is applied in many field like strain measurement, fluid measurement and displacement measurement of structural object. This method requires the sub-pixel accuracy to increase the resolution power of positioning the template image. Therefore, different types of sub-pixel estimation algorithms have been developed. One of the most commonly used sub-pixel estimation method is gradient based method and others are correlation interpolation method and intensity interpolation method. In this research, we evaluate and compare the estimation error of two types of sub-pixel estimation method by using computer simulated image. As a result, we confirm issues of systematic error in correlation method and best combination of gradient based method and intensity interpolation filter.

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The deformations of orthodontic brackets subjected to force couple produced by orthodontic wire rotation were investigated. Polycarbonate, stainless-steel and ceramic brackets were used. The wire was rotated using two stepping motors, which were equipped in an orthodontic torque simulator. Images of the brackets were acquired using a stereo microscope and two image charge-coupled device cameras, and the deformation of the brackets was measured using a three-dimensional digital image correlation technique. The total angle of rotation of the wire was 28.8 degrees. Results indicated that the deformation of the plastic bracket was larger than those of the stainless steel and ceramic brackets.

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The effects of orthodontic bracket materials and the presence or absence of orthodontic wire/bracket play on the deformations of orthodontic brackets subjected to force couple produced by wire rotation were investigated using the finite element analysis. Polycarbonate, stainless-steel and ceramic brackets were used. The finite element model consists of an orthodontic bracket, an orthodontic wire, a steel base and an adhesive layer between the bracket and the base. The total angle of rotation of the wire was 28.8 degrees. Results indicated that the deformation of the plastic bracket was larger than those of the stainless steel and ceramic brackets. Furthermore, the deformation of the brackets without the wire/bracket play had larger than that with the wire/bracket play.

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Brackets made of different materials are used in orthodontic treatment; however, the differences in stress distribution generated in teeth as a result of torque loaded with brackets of different materials are unclear. We considered the stress distribution generated in the maxillary central incisor by torque with brackets of different materials. The bracket model and wire model were a standard, 0.018x0.025 inch type. Material constants were set with respective values of stainless steel, ceramic, and polyamide. Torque was added to the wire as a load condition. The metal bracket showed a value slightly smaller than that with the ceramic bracket. The differences occurring in the stress distribution in the root were greater for the polyamide bracket, whereas the load transmitted to the teeth was reduced.

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In this study, mechanical loading test results of competition swimsuit fabrics were investigated. Also the strain energy which was stored in competition swimsuit at starting position was discussed. Current competition swimsuits were designed to adjust the human body shape for better records. At the start of competition, all swimmer wait the starting signal hi their start position, and maximum strain energy would be stored in the swimsuits. Therefore, uniaxial monotonic tensile loading test of competition swimsuit fabrics were conducted to evaluate the characteristics. Image analysis of starting position were conducted to investigate the effectivity of stored strain energy in swimsuit at starting position.

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For reduction of seismic response, many types of base isolation systems are developed. Friction mechanism is utilized in some of them. In general, responses decrease with the increase of friction coefficient. However, acceleration responses increase at a friction coefficient in some conditions of experiments. In order to examine the phenomenon using random vibration theory, mean square responses of the system with friction are calculated using equivalent linearization method. Seismic excitations are simulated as nonstationary filtered white noise. The maximum acceleration and displacement responses are obtained. In some conditions, the optimal friction coefficient exists. The optimal coefficient gives the minimum acceleration response. Isolation systems are not effective for small excitations because responses are not reduced.

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In recent years, the effect of seismic isolation structure is evaluated. Therefore, in this paper we study about the effect of the seismic isolation system in high-rise building structure. We created a mathematical model of high-rise building structure with seismic isolation layer. We analyzed the seismic response that takes the Pacific coast of Tohoku Earthquake on mathematical model. By the above result, we found that the response acceleration was decreased of the 1st layer, but the response displacement was increased. And, the response acceleration and displacement were decreased for more than 2nd layer. Therefore, we were able to confirm the effect of the seismic isolation system for high-rise building structure.

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In these years, the demand for ultra-compact electric vehicle has been increasing. The ultra-compact electric vehicle is possible to travel on poor condition roads, such as narrow and unpaved roads. Thus, the ride comfort of the vehicles is expected to deteriorate when the ultra-compact electric vehicles travel on such road. In addition, it is said that ultra-compact electric vehicles are more suitable transportation devices for the elderly. Then it is important to reduce vibration of the vehicle. To solve these problems, we suggest active seat suspension that can be installed in ultra-compact electric vehicles. In the past, we propose the control method by taking feedback from heart rate variability and switch the control using active seat suspension in order to improve ride comfort. In this paper, we examined the utility and effectiveness of the feedback control method by using real time heart rate interval which is obtained by the electrocardiogram.

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A series hybrid electrical vehicle with a bio fuel diesel engine generator, named as bio EV, is proposed in this paper. The diesel engine rotates an electric generator using straight or waste bio fuels such as sun flower oil. The hybrid electric vehicle is able to run using the generated electricity. The electric generator is also able to charge the electricity to batteries. It is expected to realize a long distance running electrical vehicle, and also a carbon neutral system. This paper will discuss the driving system of the bio EV.

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When a vehicle runs, the vibration that a road surface causes brings about discomfort of the driver and consumption of the surplus fuel. When a road surface state is bad, it is necessary to detect the irregularity of the road surface. For example, they photograph the dispersion dynamic scattering pattern that inspection light was scattered in on a road surface with a camera and detects having irregularity or not of the road surface and detects the irregularity by a millimeter wave sensor. However, they judge only an irregularity and does not think about the influence on body. In this study, we measure run data and detect the irregularity of the road surface.

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The system vibration and strain distribution of a complex machine can be predicted based on only component FE model with measured data under operation. The strain sensitivity analysis is utilized to reduce the large strain. A simple numerical model and actual model are used to verify and finally the method is applied to a vibrating screen.

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Gear noise is mainly composed of the wave of mesh frequency and the higher-order harmonics. The mechanism of generation of the mesh frequency wave has been revealed by researchers. However, the mechanism of generation of the higher-order mesh frequency wave has not been clarified yet. In order to understand the mechanism, here we show the effects of gear errors on gear noise using an experimental setup with high accuracy and compare them to numerical simulation. The results to be obtained are as follows; (1) Gear vibration obtained by the simulation using the conventional model is composed of the mesh frequency and the natural frequency of the bending of teeth. (2) Gear noise is composed of the mesh frequency and the higher-order harmonics. Therefore, the model which reproduces the higher-order mesh frequency is required in future.

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This paper is intended to improve the accuracy of the rattle noise evaluation method using a shaker. In the conventional method, there was a problem that can't detect the occurrence of a little sound of rattle noise due to the radiated sound from the shaker. In this study, we investigated the characteristics of the radiated sound of rattle noise, and examined the valid evaluation method to detect the occurrence of rattle noise. As a result, by extracting the radiated sound of a specific frequency range, it was shown that we can make evaluations of the presence or absence of rattle noise and identifying the generation frequency even in measurement environment that contains the sound of radiated from the shaker.

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Helmholtz resonator (HR) is a device for noise reduction. It is effective in reducing noise that has a dominant frequency component. However, in some other frequencies, it makes the sound pressure increase. Therefore, it is necessary to reduce the effective sound pressure (root-mean-square, ESP) in a certain frequency range and it is one of effective methods that acoustic material (AM) is inserted into a HR for damping. In this study, the relation between resonant frequency of HR and ESP, and the relation between amount of AM and ESP are investigated through a numerical analysis and experiments. As results, appropriate resonant frequency, size of HR and amount of AM inserted are revealed. The guidelines for designing HR with the use of AM to reduce ESP are obtained.

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