Many houses were destroyed in destructive earthquakes in the world. Then, control of seismic response of house is important for protection from destruction. In this paper, two story houses are focused on and oil dampers of some shapes are proposed. Oil damper is connected to the ceiling of the first story and the foundation. The spherical damper and the rectangular parallelepiped damper with silicon oil are proposed. The effectiveness of the dampers is examined experimentally. It is concluded that the peak of the frequency response function of the first vibration mode decreases and the damping ration increases when the dampers are used. From simulation method using the analytical model, it is found that the maximum response decreases when the dampers are used.

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Many houses were destroyed in destructive earthquakes in the world. Then, control of seismic response of house is important for protection from destruction. In this paper, two story houses are focused on and oil dampers of some shapes are proposed. Oil damper is connected to the ceiling of the first story and the foundation. The spherical damper the cylindrical damper and the rectangular parallelepiped damper with silicon oil are proposed. The effectiveness of the dampers is examined experimentally. It is concluded that the peak of the frequency response function of the first vibration mode decreases and depend on amplitude of excitation. dampers are used.

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The effects of vibration suppression of a shear-type, moment-type and shear and moment-type dynamic vibration absorbers to a simply supported beam are discussed theoretically and experimentally. The dynamic vibration absorbers are composed of a mass and a three-layered cantilever beam using copper plates and viscoelastic material.

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A dynamic damper using a Mn-Cu high damping alloy spring to reduce vertical vibrations of pedestrian bridges is proposed. This paper presents an experimental study for evaluating effects of the number of repetitive deformation by vibration on damping properties of the Mn-Cu alloy spring. First, a vibration test of 10^5 cycles and a free vibration test using 4 cantilever models composed of Mn-Cu alloy plate and a weight are carried out to investigate the damping properties of Mn-Cu alloy plate. Further, the same vibration tests are repeated ten times to 10^6 cycles. From these results, the effects of the repetitive number of vibration and vibration amplitude on the damping properties of Mn-Cu alloy plate are clarified.

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An electrical generating system using piezoelectric element (PZT) is proposed to convent a useless vibrational energy into electric energy. This paper describes the electrical generation characteristics of PZT added Nb and laminated PZT under vibration load. Vibration tests are performed using an experimental equipment composed of PZT, weights and rubber. Sinusoidal wave excitation tests are carried out under the condition of the constant initial compressive load acting on PZT. Effects of the number of laminate, vibration frequency and vibration load on generated voltage and electric power are evaluated.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades fatigue strength. The authors propose a new method for reduction of tensile residual stress in which ultrasonic vibration is applied during welding. First, transmission of ultrasonic vibration is examined. Second, reduction of residual stress using ultrasonic vibration is examined. It is concluded that ultrasonic vibration is transmitted to specimen well and residual stress is reduced using ultrasonic vibration.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades fatigue strength. The authors propose a new method for reduction of tensile residual stress in which ultrasonic vibrations with different frequencies are applied during welding. First, transmission of ultrasonic vibrations is examined. Second, reduction of residual stress using ultrasonic vibrations is examined. It is concluded that ultrasonic vibration is transmitted to specimen well and residual stress is reduced using ultrasonic vibrations with different frequencies.

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FRP composite materials are used for many structures because of high strength ratio. FPR composite material machined in order to connect to other materials. Surface roughness becomes large because of delamination. In this paper, drilling is focused on and machined surface is improved using ultrasonic vibration. Width of flank wear, thrust force and moment using ultrasonic cutting are compared with those using conventional cutting. It is found that width of flank wear is improved when ultrasonic cutting is used.

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Welding is widely used for construction of many structures. Residual stress is generated near the bead because of locally given heat. Tensile residual stress degrades fatigue strength. The authors propose a new method for reduction of tensile residual stress in which ultrasonic vibration is applied during welding. First, transmission of ultrasonic vibration is examined. Second, reduction of residual stress using ultrasonic vibration is examined using heater instead of welding. It is concluded that ultrasonic vibration is transmitted to specimen uniformly and residual stress is reduced using ultrasonic vibration.

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National curriculum of junior high school is revised, and students must finish all four learningfields in technology learning; manufacturing, energy conversion, information and cultivation. But, learning hours of technology aren't increased. It is difficult that students learn all technology fields in 87.5 hours. So, a comprehensive teaching material including four learning fields is developed. A class is practiced based on a teaching plan of the developed teaching material. It is clarified that this teaching material is able to be introduced into the technology education of junior high school from the result of the class practice.

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The mechanic contents of materials and structure in junior high school technology education was extracted in terms of the strength of materials and the structural mechanics. The extracted contents were analyzed considering the force action in the material and structure. The analyzed results were classified on the basis of morphologic models in strength of materials and structural mechanics. The classified morphologic models were shown in following nine models: Bending strength in simply supported beam, bending deformation in cantilever beam, shearing force, moment of inertia of area, rigid frame structure, planar structure, rigid joint, hinged joint and truss structure. The results of the questionnaire showed that the junior high school students were hard to understand about the condition of force action and the direction of resistant force in material.

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Thickness of the cardboard used here is around 0.5mm. Large space and big tools are not necessary for the cardboard handicraft, so it can be performed in ordinary lecture rooms. The handicraft was used for several lectures on introduction to manufacturing in our university. It was found to be effective to catch students' interests for manufacturing. In order to extend the capability of the cardboard handicraft, mechanical characteristics of the cardboard, such as 3-dimensional deforming ability, strength of bearing holes and screw holes, were examined. Through experiments and trial productions, it was found that some mechanical structures can be made with the card board.

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Recently production educations of robots and mechatronics have been popular in junior high schools and engineering high schools and consequently the education of mechatronics and system control is important in the technology education department of teachers college. However mechatronics and system control educations have not been sufficiently done in the teachers colleges. In this study, we developed the education program of mechatronics and system control through design and production of inverted pendulum car. We had the class using the program and evaluated the program. The result of program evaluation shows that the developed program is very effective in mechatronics and system control education.

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In the mechanical engineering of university and technical college, design drawing and practical training in mechanical workshop is adopted as basic mechanical training subject. In this subject, students can learn the basic technology, however, it is difficult that students learn manufacturing technique with originality and creativeness. In Mechanical Department of Tokyo National College of Technology, the expansion of the creative education has been challenged. In this paper, trial education of creative robot manufacturing to aimed at improved creativeness is described. Robot production practical training practiced in our College was described. The following are shown: The educational contrivance who students pull the interest, the teaching effectiveness besides.

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The designer's creativity, figure reasoning capacity, and spatial reasoning capacity, to say nothing of all the artificial things the fact of having brought the society as a whole the change, in innovation of design business, the aspect of the CAD design process changed a lot. However, the figure expression by a certain hand dawning technique did not necessarily fade from the former. So, in the main subject, it performed investigation about Diagrammatical Thinking by hand drawing being more important before study of three-dimensional CAD than before the educational viewpoint.

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As we come to use digital engineering technology for a product design, we get possible to do a calculation of strength/vibration in short time, that we used a detailed three-dimensional model. However, in order to design efficiently, it is important to find the most suitable design parameter in a model simple as possible by replacing structure of a product at planning phase (basic design). We developed a design tool to help basic design of machine elements for a young engineer. Characteristics of this tool are as follows. It is easy to understand a procedure of a design. We can compile design policy. By using materials database and calculation tools linked to each procedure, we can calculate and can evaluate a result and can store those results by a fixed form style. We show an example that applied this tool to design shaft.

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This paper is a instance of new practical education used 3D graphics in the field of engineering except mechanical engineering such as electronic devices. Over the past few years a considerable number of studies have been made on engineering education system using 3D CAD in the field of a mechanical design. A core of curriculum is 3D CAD skill in the field of designing and drafting course, because it is an increasing interest in manufacturing systems as concurrent engineering used 3D CAD in the recent industrial world. However, little is known about engineering subjects except mechanical engineering. We are concerned with a concurrent education using 3D graphics in the field of electronic devices. We come to the conclusion that the education of engineering using 3D graphics will go a long way toward promoting understanding of students.

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We have conducted to develop the computer assisted instruction system which provides an e-Learning environment for drawing practice. The system is intended to be used for exercises without the help of teachers, so that the function to check on dimension lines missing in technical drawings is implemented. In this study, the developed system was applied to the exercises for indicating dimensional information on drawings in the class of "Machine Design." Submitting drawings by the students show that the system is effective to notify the lack of dimensional information. Results of the questionnaire suggest that more kindly user interface and manuals are required for using the system.

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Stirling engines have been used frequently for the explanations of the environmental and energy saving education, because they have excellent characteristics which are high thermal efficiency, multi-fuel capability and low pollution. Since Stirling engines work relatively in the range of low gas pressure compared with the internal combustion engines, the models of Stirling engines have been used as teaching materials in the thermal energy educationl. However, the principle of Stirling cycle is difficult to understand. In this class, in order to promote the understanding of the principle of Stirling cycle, three different instructional materials of engine were used and an e-learning CG animation content was used for the sake of making the understanding of the principle of Stirling cycle firmer.

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We believe that FE analysis technique education by which one can learn how to use FE analysis program is effective and necessary, concerning that general purpose FE analysis programs are widely used in every engineering field. In this study, we proposed the contents of FE analysis technique education and the analysis exercises using general purpose FE analysis program for students who had already learned basic theory of FEM, in case of using it on purpose of structure analysis. Then, we practiced the analysis exercise lecture for the third grade students of Tokyo Gakugei University, decided criterions for evaluation and examined their student's achievement level according to it. As a result, all most students were able to obtain the good evaluation for the criterions. The proposed contents of education and analysis exercises made the students acquire a basic FE analysis technology.

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The effectiveness of learning by experience is evident especially for the school children studying science, but it also works well for the elder students. Ashikaga Inst. of Tech. has been participating in the High School Science Camp conducted by Japan Science and Technology Agency since Spring 2003 with the program entitled "Let's learn on renewable energy by experience". In the program, students have to build solar cookers and small wind turbine introducing their own ideas. A Telkes type solar cooker is employed as one of the options they can choose to adopt their own plans. Some of the modifications taken by the students are quite unique and effective contrary to our predictions. The mechanism how they worked efficiently is studied analytically with the ray tracing technique numerically.

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Dye-sensitized Solar Cell (DSC) is the solar cell using photo-catalytic material ble anatase type titanium oxide as photo voltaic device. Since the DSC could be fabricated by atmospheric process, this solar cell is hoped to be a educational material for mew education as well as practical solar cell. In this report, the structures and photo voltaic properties of the DSCs we developed for use in UNESCO school and winter science camp are introduced

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Recently, despite a flood of the embedded system product, shortage of embedded systems engineers has become aggravated. Because it is given that the knowledge of various fields is needed for the acquisition of the embedded system technology and the engineer's education is difficult. Embedded systems are at the intersection of electrical engineering, mechanical engineering and computer engineering. This paper describes our efforts in structuring new teaching materials of the embedded systems to an existing curriculum. In the approach, we examined whether it was suitable for the technical high school student's ability. And the student participated in the relating contest, and felt the result with the pleasure of the production directly.

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This study aims at developing an educational FA model in order to make students understand what sequence control is. In addition, the FA model includes PLC and SCADA through the Ethernet so as to show the latest sequence control and how to make rudder programs and SCADA projects. In a field of education, sequence control is considered to be behind the times. However, It is still used mainly and growing in production fields.

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This paper mentions a practical educational effect of engineering on monozukuri technologies using Formula SAE_[○!R] Project. Formula SAE_[○!R] is a student design competition organized by SAE International (formerly Society of Automotive Engineers). The concept behind Formula SAE is that a fictional manufacturing company has contracted a design team to develop a small Formula-style race car. The prototype race car is to be evaluated for its potential as a production item. The objectives of this paper are to see the activity of Formula SAE_[○!R] Project as an active learning and to discuss the future of Formula SAE_[○!R] Project in Shonan Institute of Technology.

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For the "countermeasure for younger to moving away from the sciences" and the "promotion of fundamental technology for manufacturing", it is necessary to cultivate human resources abundant in creativity. So, this festival is intended for participators to plan, design, and make the "air-engine" car powered by natural energy with thinking by themselves. The "air-engine festa" was held for the purpose of going through the sensation and delight of finishing the work and deepening the interest to the science through this contest.

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The Innovation Center for Research and Engineering Education has contributed to promote innovative and creative mind for students in engineering. It not only provides various educational programs and events for students, but also supports teaching staff to carry out such educational and research programs. The paper describes the new engineering education program linked master course with faculty at faculty of engineering department in Utsunomiya university.

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It is essential for both universities and industry to share and agree upon the desired capabilities and qualifications of engineers. It is also important and fruitful if the industry is involved in engineering education in the university. Utsunomiya University, Fuji Heavy Industry, NDK Electric, and SOLABO formed a consortium to discuss and develop a program to enhance mechanical engineering education.

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This paper describes a new virtual reality-based skill training and human resource development for undergraduate mechanical engineering students. The virtual reality-based skill training system is able to reproduce the environment of a casting and a lathe manufacturing technology. The most notable advantages of this system are that students can virtually experience the workflow prior to actually performing the practice at the worksite, one can learn about procedures beforehand. Virtual reality technology is used to stimulated environment of the students. Our skill training allows the students to experience the perception of actually being in a particular environment.

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Environmental measurement by students of "College of Technology" and residents have been carried out in east area of Tokyo (Sumida, Koutou, Katsusika, Arakawa, Adachi, Edogawa, Taitou, Kita Awards) since 2002. These measurement summaries and impression of students and residents are introduced.

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Types of students at Japanese universities can be classified into six categories, and education and opportunities needed and desired for these students are discussed, with international and global perspectives taken into consideration. The importance of liberal arts education for science-, engineering- and technology-oriented students is also discussed, and recommendations are made for education of these students.

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The present state of the technical education was discussed from the view of the money and business. As a result, the treatment of the engineer of the science course in the society was worse than the liberal arts course, and it was clarified to deprive of the interest in young person's science course

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As a technique to monitor the mechanical conditions of composite/metal fastener joint structures, authors proposed a "Smart bolt" with embedded optical fiber sensor in it. In this study, the tensile test with a loosening fastener and the damage test of the multiple-row fastener joint specimens were conducted. Based on the experimental results, it is shown that, for both the multiple-row fastener joint specimens of in-line double rows and stagger row, the loosening case of adjoining fastener around Smart bolt can be detected.

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This paper provides a reliability of solder joints on electronic devices. This study clarifies a dependency of the surface tension in liquid lead free solder (Sn-Ag-Cu alloy system) on plate temperature under inert gas condition filling with Nitrogen. The surface tension of the lead free solder based on the Laplace theory is obtained numerically by using sessile drop profiles as boundary condition. The sessile drop profile is measured by the optical image method with CCD camera. Effects of the plate temperature on the surface tension are clarified experimentally. The results contribute development of geometrical shape design of the solder joint on the electronic devices.

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Structures absorb the energy from earthquakes and build up it as damages. In some areas that have many earthquakes, structures are often damaged from them. Therefore, damage detection method using earthquake excitation is found to be useful for these damages. In this paper, the integrity investigation of structure using excitation response to wiiite noise simulated seismic motion via SI-F method is suggested. The SI-F method is the reasonable damage detection method. In this method, the damages will be detected from the change of correlation between some sensor outputs.

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This paper reports noticing circular holes, which are always applied to reducing weight and connect channel in cylindrical shell structures. Thin cylindrical shells with circular holes causes to fall this strength. Therefore, holding this vibration characteristic will find a solution to make holes. This research analyzed the natural frequency characteristics and effects of the circular holes of thin cylindrical shells by FEM analysis and experimental. As a result, the authors verified when the shell was thin and the hole was near the clamp end, the effects of holes increase. Consequently, thin cylindrical shells with circular holes need reinforcement around the clamp end.

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The 755 accidents happened between 5 years about the doors of the car. The case across finger and hand was 87%. The crash force of the sliding door (231kgf) was bigger than he crash force of the hinged door (95kgf). Accidents happened "The slide door closed suddenly and got a blow across the thumb in the slope of the steep grade" and "The man broke the finger of left hand in second and third. Because of sandwiched by the door". I think that an indicator for the safety of the sliding door is necessary. I simulated a finger sandwiched with a sliding door in dynamic analysis software LS-DYNA. I made a sliding door and a finger model in this study. I confirmed the mechanism about strength of the bone and influence tof the sliding door about the speed and the mass.

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Our aim of this study was clarify a mechanism about generating unsteady flow force in human swimming motion. Therefore, we tried to compare the forces obtained by using the robot arm in three methods which are a direct force measurement, a prediction by the quasi-steady theory and estimation by the flow visualization (PIV). The maximum measured force was reached 13.8N soon after the start of stroke movement in the direct force measurement method. The quasi-steady resultant force was almost constant (about 5N) from the beginning to the end. On the other hand, estimated forces based on the principle of conservation of momentum from the flow visualization corresponded to the force directly measured. These results reveal that the generating force in swimming is well explained by the momentum analysis of flow rather than by the quasi-steady theory.

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A flow in a channel, which consists of an introduction channel and two symmetrically bifurcated channels having high aspect ratio rectangular cross-sectional areas, was analyzed by direct numerical simulation. The introduction channel is expanded in the bifurcation direction at the bifurcation point, where a flow in its direction is generated. As the result, the mainstream profile in the introduction channel varies; the velocity near the sidewall gains and the velocity at the center is reduced. In accordance with the reduction rate of the velocity at the channel center, the region, in which the bifurcated channels affect the flow in the introduction channel, can be determined. Each flow in the bifurcated channels resumes the fully developed profile downstream.

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We developed new-type hoses for making the efficient firefighting strategy, and weighed them against existing firefighting hoses. And we measured the pressure loss of water and compressed air foam (CAF) through hoses. The result is summarized as follows. The pressure loss of CAF is less than half that of water. The pressure loss of water through the new-type hoses is about half of that through the existing hoses. The new-type hoses are harder to create kinks and better traumatic durability than the existing hoses.

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We developed new-type nozzle for efficient fire-fighting strategy, which uses compressed air foam (CAF) efficiently. In this paper, we compare spray range characteristics and foaming magnification of the prototype nozzle with these of existing nozzles. To decide these characteristics, we used actual equipments which are used in efficient fire-fighting strategy. The result is summarized as follows. Spray range of the prototype nozzle is even with or superior to that of existing nozzles. The foaming magnification by the prototype nozzle is far superior to that by existing nozzles.

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The shock wave can be found, for example, in the muffler of a car engine, in case of the explosion of gunpowder, the airplane of a supersonic flight, etc. A study of a shock wave is very important in engineering field. Therefore, in this paper, the behavior of shock wave discharged from the pipe end is studied. The shock wave is generated using the shock tube(MO-tube). The flow fields while the shock moves downstream is visualized using shadow photography and schlieren photography. The propagation of shock wave and the phenomenon of the occurrence of thin vortex ring are examined and discussed.

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An underexpanded jet is widely applied in industries. When the underexpanded jet impinges on an object, a stand-off shock wave forms in front of it, with different geometries and locations depending on operating conditions of jet and shapes of the object. In this study, experiments are made on the underexpanded jet blown against the cone whose angles are 60 deg and 120 deg. To understand the flow field of underexpanded jet impinging on cone quantitatively, density distributions are obtained by applying Mach-Zehnder interferometry (MZI) and the corresponding pressure distributions on the cone surface are measured with pressure tap. Velocity distributions and streamlines are also estimated using the density distributions.

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An interesting phenomenon so called hysteresis in magneto-rheological (MR) fluid appears when a magnetic field is increased to and decreased from a certain value. This phenomenon appears to be caused by the formation of robust clusters in proportion to the magnetic field intensity. Results show that the hysteresis in MR fluid are different in comparison with the magnetic fluid. It seems that cluster formation in the MR fluid breaks more quickly and eventually becomes the same as the initial conditions after the external magnetic field intensity is zero.

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Wells turbine is one of self-rectifying turbines which is utilized to extract mechanical shaft power in wave energy converters with oscillating water column (OWC). This paper presents the investigation on the performance of Wells turbine with the NACA0020 blade profile by means of numerical method using a computational fluid dynamics (CFD) code. The investigation is carried out on the numerical model with uniform tip clearance of 0.5 mm and l mm under steady flow condition. As a result, it was shown that the numerical method has been able to provide the reasonable result of the turbine performance qualitatively and quantitatively. It was also shown clearly that the effect of tip clearance influences significantly on the turbine performance.

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In Japan, "Natural energy" is expected to play a part in improvement of the self-sufficiency of energy supply. Micro hydropower has great potential water power. Micro hydropower is mostly in "run-of-river", without dam or water storage. It is one of the most environmentally benign technologies and is useful for local independent power supply. However, the cost performance is the principal obstacle to familiarize micro hydropower widely. In this study, for price-reduction of micro hydropower, I made stator vane which was made of PVC board and pipe and a propeller of outboard motors was applied to a turbine blade. The turbine blade was improved to achieve high efficiency and increased output, the micro hydropower performance was examined by experimental study. As a result, the best performance was obtained as the output of 1.503kW.

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Recently, environmental problems of global warming etc. have come to stand out gradually by the volume consumption of the fossil fuel. Power generation in this using natural energy is paid to attention. There is wind power generation as the one. In the present study, it has aimed to experiment by using the vertical axis type pinwheel, and the reverse-..".. to examine the performance and the utility of the pinwheel for wind power generation calling the Cygnus mill ..the use of the wing that becomes like the character of .. piling up... When the number of sheets of the braid is changed into two, three, and four pieces, the following has been understood. (1) Power generation increases by the number of sheets little at the low wind speed. (2)The Z=3 piece is suitable at a high velocity of the wind. (3) Power generation increases by the wingspread large.

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In this study, unsteady fluid forces acting on a discoid airfoil simulating a human hand in the sinusoidal pitching motion were measured by using a ring structure 2 elements balance, and also the flow visualization technique was used to aid in understanding the flow field in the near field of the airfoil edge for the wind tunnel test. Furthermore, the vortex-shedding frequency was estimated by the FFT analysis. The unsteady fluid forces were affected by the behavior of vortices shedding from the airfoil edge during the pitching motion, and the flow structure due to the vortex behavior was strongly affected by the reduced frequency.

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Many birds increase by flapping the wing and the whole wing is flexibly moved this time. This movement produces a difference in the air resistance. The air is grasped enough, when the wing is moved in the downward direction. The air is released from the clearance of the wing, when the wing is moved upward. It is considered to apply this mechanism to the bird type wing of the wind turbine. In the paper, wind collector suitable for this vertical axis wind turbine is produced, and collection wind characteristics by the wind direction have been clarified experimentally.

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Unsteady fluid forces acting on a discoid airfoil were investigated by changing an angle of attack impulsively. The relationship between the transient aerodynamic characteristics and the vortex behavior was described with the flow visualization technique during stepwise incidence variation. The impulsive lift deviates far from the static values in the cases of a small angle of attack change (a lower value than a static stall angle) and low rising rate. When the vortex developed at the trailing edge flows away, the dynamic lift significantly increases and the deviation from the static characteristics enlarges. The changes in the transient aerodynamic characteristics are caused by the vortex shedding from the trailing edge of the airfoil.

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