Monitoring data obtained at a seismically isolated building in Tokyo during the 2011 off the Pacific coast of Tohoku Earthquake are analyzed to investigate the changes in the modal parameters of the building, which are generally used as global soundness indices in structural health monitoring, in correspondence with the response amplitude of the building. The results show that the natural frequency decreases as the response increases and then regains its value as the response fades, where the value at the end is lower than that at the beginning.

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We have developed a novel relative-story displacement sensor for structural health monitoring which is capable of measuring the 5-DOF movement of building layers. Three pairs of infrared-light emitting diode arrays and position sensitive detector units were used for simultaneously measuring the relative displacement, the local inclination angle, and the torsion angle between two adjacent layers. For verification, laboratory tests were carried out using a shaking table, a motorized micrometer, and a rotation stage. In the static experiment, it is verified that the local inclination angle and the torsion angle can be measured as well as the relative-story displacement using the sensor system. The resolution of the sensor system in the displacement measurement, that in the inclination angle measurement, and that in the torsion angle measurement were evaluated to be 0.10 mm, 34.4 urad, and 14.6 urad, respectively. In the dynamic response experiment, the accuracy of the sensor system was experimentally evaluated to be 0.20 mm in the relative-displacement measurement, 110 urad in the inclination angle measurement, and 90 urad in the torsion angle measurement, respectively. These results indicate that the developed sensor system has a sufficient accuracy for structural health monitoring.

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This paper concerns a structural health monitoring (SHM) methodology, self-sensing,sensitive and baseline-free, that can detect and characterize local structural damages in early stage, named nonlinear piezoelectric impedance modulation (NPIM) method. In this work, Bending fatigue tests are conducted using a specimen with a pinhole, and the development of the fatigue crack is detected by the NPIM method. It is shown that the proposed damage evaluation index which removes the effect of the damping fluctuation has a good correlation with the extent of the fatigue crack even in its early stage.

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An improvement of cumulative sum (CUSUM) chart when it is applied to monitoring of plant state variables is suggested. In order to detect abnormal states by watching variables without settled target values, a strategy based on accumulation of sums of difference from moving averaged values is proposed. With this approach, one can detect only rapid condition changes and can neglect slow drifts caused by, for example, long-term degradations which can be detected by other tools. Moving average with varying weight is proposed to make the method robust for wide range of condition change speed. An application to lubricant oil temperature monitoring of a gas turbine co-generation system (combined heat and power plant) is also presented.

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A model-based performance monitoring method for a heat utilization process in a distributed energy system is developed in this study. The performance monitoring has three components: a static input-output model for the target process, a dynamic compensation function, and a failure detection function. First, the static input-output model estimates the output process variables in response to the variations in the input process variables. Then, the dynamic characteristics of the output process variables are provided in the dynamic compensation function where they are indentified as first order lag systems. Finally, the estimated output process variables considering the dynamic characteristics are compared with the measured output process variables in order to detect device failures. Through a numerical simulation for a heat utilization process in a gas engine cogeneration system that has a radiator with a considerable lag characteristic, the effectiveness of the developed performance monitoring method in a transient state is verified. The result shows the sufficiency of the estimation accuracy of the output process variables and the capability of detecting device failures in a transient state.

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To avoid failures of an air-conditioner, we need suitable condition monitoring technique. Unfortunately, an air-conditioner has many parameters in it, i.e., inlet temperature, outlet temperature of a condenser or an evaporator, pressure at each component and input power to compressor and so on. Furthermore, it is very difficult to identify failures in an air-conditioner because of small difference of parameter between normal and abnormal condition. In this paper, we proposed diagnosis technique by using SVM (support vector machine) with identified system parameters by ARX model. Because dynamic property of an air-conditioner identified by ARX model, did not depend on operation condition, i.e., room temperature, outside temperature, our proposed technique did not need a lot of data. Finally, our proposed technique well identified clog in heat exchanger very well.

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The problem that the drainpipe in the power plant get blocked occurs. The blockage part of pipe has been presumed based on the experience so far. However, it is impossible to detect the blockage part surely in conventional methods. In the present study, the new method is investigated,which is to detect the blockage of the drainpipe by the vibration analysis. The vibration measurement and the modal analysis are done in the present study. The natural mode, natural frequency, and the experimental modal damping ratio can be obtained by this experimental analysis. In this experiment, pipe and U bolt of actual piping system are used, and compound of clay and sawdust is used as blocker. As the experimental results, it has been understood that the modal damping ratio of the blockage drainpipe is larger than the modal damping ratio of normal drainpipe.

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Some factors such as arc between contact wire and contact strips of a pantograph cause wear on the contact strips. Once the local wear occurs on the contact strip, it is highly likely to grow into a step-shaped wear pattern. A contact strip with this step-shaped wear may lead to accidents such as contact wire breakage. To prevent such accidents, the authors have developed a method of detecting step-shaped wear on the contact strip by measuring the vibration of the contact wire. This paper describes this new method and the results of some experimental testings.

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The finite element method(FEM) has been used in the vibration analysis of the rotating shaft in order to identify the rotor crack in its early stage. This paper investigates the concise 1D-FEM rotating shaft with an open crack for the quantitative analysis. The open crack is represented as the decrease of the area moment of inertia around the crack position. Two models are investigated: one is the exponential decrease model and the other is the linear decrease model. The procedures to determine the parameters in these models are developed, and the characteristics of these models which should be noted in utilizing them are clarified.

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A smart sensor is required if we are to popularize health monitoring using the vibration of a structure. This device is used to evaluate the vibration characteristic of the structure. To detect the variance in the vibration characteristic from the vibration data of a structure, a time-frequency analysis technique that can detect the change of the frequency components of the vibration data over time is needed. This report proposes the real-time data processing method with narrowband band-pass filters based on the one degree of freedom vibration system for the evaluation of structural vibration characteristics. This method is applicable to processors with low computation loads and memory capacities.

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For employing Condition Based Maintenance (CBM) systems, laying cables for transmitting signals and supplying power have been a problem. We have developed a condition monitoring system using wireless signal transmission combined with energy harvesting, which eliminates the need of cables. Use of wireless signal transmission eliminates the need of signal cables, but does not eliminate power cables. Energy harvesting, a technology obtaining energy from environment, solves the problem of power cables, though the electric power obtained by energy harvesting is not sufficient for conventional sensor systems for CBM. We have solved this problem by using a low power Micro Controller Unit (MCU) and low power sensors applying Micro Electro Mechanical Systems (MEMS) technology. The condition monitoring system performs seismic monitoring and vibration monitoring of rotating machines.

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The problem in ceramic grinding is a tool failure after a long time operation. It causes the decrease in the product quality and productivity. Usually, rotation frequency and its multiples are utilized for machine condition monitoring. However, it is difficult for us to clearly observe the frequency components in the ceramic grinding by direct use of the Fourier transform. In this research, we measure the acceleration of the work piece during the grinding process, and the Hilbert transform is used as a pretreatment of the Fourier transform. Significantly good results are obtained by the proposed method.

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The adhesion state of a heat seal used for a cup type container is evaluated only by viewing now. The purpose of this study is a nondestructive evaluation of the adhesive strength of the product using the heat seal. Therefore we evaluate the adhesion state of a heat seal, using ultrasonic wave. The ultrasonic frequency is affected by passing the object inside. We take notice of the frequency modulation of ultrasonic wave. Therefore we apply Hilbert conversion and calculate the frequency modulation of ultrasonic wave. And we estimate the state of the adhesion layer from the change.

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In this paper, a strain sensing system using piezoelectric ceramics is developed to monitor the feature of strain history of structural member. The system is a rectangular box made of thin aluminum plate, in which piezoelectric element, electric circuit including charge amplifier, signal processing unit, and battery are facilitated. The device is bonded onto the structural member by using adhesive agent, and counts the number of cycles of dynamic strain by Rain flow method. In order to see the performance of the system, experiments are carried out using a fatigue testing machine. As the result, it is clarified that proposed strain sensing device can measure the dynamic strain of structural member.

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Welding is widely used for construction of many structures. It is well known that residual stress is generated near the bead because of locally given heat. Tensile residual stress on the surface degrades fatigue strength. On the other hand, welding is used for repair of mold and die. In this case, reduction of residual stress is required because of protection from crack of welded part in mold and die. In this paper, a new method for reduction of residual stress of welded joint is proposed for repair welding of mold and die. In this method, low frequency and ultrasonic vibrations are used during welding. Thick plates are used as specimens of mold and die. Residual stresses are reduced when low frequency and ultrasonic vibrations are used during welding. Experimental results are examined by simulation method using an analytical model. One mass model considering plastic deformation is used as an analytical model. Experimental results are demonstrated by simulation method.

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This paper describes a method to investigate the relationship between cytoskeletal deformation by mechanical stimulation and its corresponding intracellular signals for identifying mechanosensors of cells. Gene transfection of green fluorescent protein to osteoblasts enabled visualization of actin in cells. When local shear deformation was applied to a cell by a micropipette, the distribution of cytoskeletal actin deformation in the whole cell was automatically obtained from the two images of the cell before and after deformation by using KLT method. Calcium ion signaling response to the same mechanical stimulation was measured as the spatial and temporal changes of fluorescent intensity of fluo-4 loaded to osteoblasts.

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Cell nucleus is full of various components, and has complicated and heterogeneous structure. Though most functions of nuclear domains have been well studied, stiffness of nuclear have not been studied. In this study, the experimental system was developed to measure the stiffness of living cellular nucleus in order to verify the inhomogeneity of the cell nucleus. The system is composed of two devices: a sensor which can measure stiffness of micro cell nucleus, a rotatable device which can locate and rotate the nucleus horizontally. The devices are assembled on the stage of an inverted phase contrast microscope. Experimental studies have been carried out by using normal human osteoblast. The method has shown capability to detect difference of stiffness on cell nucleus. The result shows that there is significant difference between nucleolus and other nucleic domains. In addition, it is found that the stiffness difference of cell nucleolus is clearly shown through making stiffness contour map.

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According to previous studies, when some mechanical vibration is operated to osteoblast-like MC3T3-E1 cell, proliferation of the cell depends on the frequency and acceleration amplitude of applied vibration. But there are lots of unsolved mechanism between biomechanical stimulation and cellular behavior. In this study, the attention was focused to the effects of mechanical vibrating term on cultured osteoblasts. Cells, MC3T3-E1, were seeded in three culture plates. After seeding, the three plates were left still in a CO_2 incubator. And two plates were excited by electromagnetic exciter at frequency of 12.5Hz and acceleration amplitude of 0.5G in the incubator. Non-stop vibration was applied to one of two plates, which was called "group 1". A regular-term vibration was given to another plate, called "group 2". One plate was set still without vibration, called "control group". Cell density was measured and the medium in plates was changed every 3days. The difference between control group and vibration group was investigated by the growth curve.

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In this study, the influence of vibration stimulation to cultured undifferentiated human iPS (induced Pluripotent Stem) cells was investigated. Three-dimensional micro vibration stage was used to stimulate the cultured cells. This stage can excite three-dimensional vibration with total amplitude up to around 30 urn in each (x, y and z) direction. The diameter of mountable culture dish onto the stage is 35 mm. For the experiment, human iPS cells co-cultured with SNL 76/7 cells as feeder cells are provided. By using the stage, the cells were stimulated with horizontal or vertical vibration as a mechanical stimulation. Frequency of the vibration is set at 10 Hz, and total amplitude it is set at 30 um. As a result, there is no significant difference in proliferation rate between stimulated cases and statically cultured case. However, the result suggests that the horizontal vibration stimulation might accelerate proliferation of undifferentiated human iPS cells.

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This paper described development of a micro device which applies mechanical vibration stimulation to focal adhesions of a cell. In recent years, evidence has been growing that focal adhesions act as mechanosensors of cells which convert mechanical force into biomechanical signaling. However, there are no effective micro devices which can directly apply mechanical stimulation to each focal adhesion. Here we develop a micropillar substrate embedding micron-sized magnetic particles and enabling the micropillars to be deflected by external magnetic field. The combination of long and short micropillars produces the difference of deflection between them and enables the micropillars to apply deformation to cells. The long pillars were periodically deflected at the amplitude of approximately 1.4 μm whereas many of short pillars were not deflected. The cell culture on the magnetic micropillar substrate revealed that this device can apply periodic deformation to focal adhesions of a cell. These findings indicate that the present micro device can be used for investigating mechanosensing systems of a cell.

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An erythrocyte is represented using viscoelastic model with two degrees of freedom that spring is connected parallel to dashpot to estimate dynamic deformability quantitatively. To identify such parameters as an elastic modulus and viscous damping coefficient of the model, erythrocytes were deformed in the experiment using periodical share flow field. In this research, we used erythrocytes of normal subject, and changing deformability of some erythrocytes was provided glutaraldehyde to treat hardening treatment. The displacement of the center of gravity ΔG and the deformation quantity of major axis ΔL are obtained from time series of images. Both of the data are periodic on movement and deformation of erythrocytes. Based on the experimental data, parameters of viscoelastic model were identified. The estimation method of dynamic deformability about erythrocytes was examined. In the result, it was found that dynamic deformability of human erythrocyte can be estimated using viscoelastic model with three elements. And the simulation results using three elements model simulated experimental results more particularly than two elements model.

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For the homeostatic control, there are Ultra Low Frequency (ULF) fluctuations on the backbone of the control. We think we can extrapolate state of human by capturing variation of ULF fluctuations. In this study, a method was conceived for capturing ULF fluctuations by performing the time series of the gradients analysis of the pulse wave taken from the surface of the back, which was defined as an aortic pulse wave (APW) with zero-cross detection method or peak detection method. APW was recorded during an experiment with an induced sleep test in the sitting position. The results indicated that we can find drowsiness, a predictive signal for falling asleep and an impending sleep by catching variability of 0.0017Hz, 0.0035Hz and 0.0053Hz of ULF fluctuations of APW obtained by the analytical method we had invented.

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Previous researches suggest the stiffness index in different state of arterial vessels. They approximate arterial vessel as the thin circular cylindrical shell based on DonnelFs theory and Flugge's theory. These studies illustrate the changes of stiffness in different thickness, and different materials. Present study proposes the primary mechanical model based on Love's theory. Furthermore in order to confirm the result of model, the experiments were carried out on different artificial tubes. These tubes created by different material in different thickness. The circulating circuit is applied as the circulatory system of human body, and water is designated as the working fluid of the circulating circuit. Tubes were setup in this circuit. Experimental data applied for mechanical model and mechanical parameters identified using Downhill simplex method as the inverse problem. In this study stiffness index and damping ratio were identified and the result of Love's theory was compared with measurement data and DonnelPs theory. The result shows that present study can confirm the measurement data with the fine approximation.

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This paper describes an active control system intended to minimize the vertical vibrations transferred from the vehicle seat to the head. This system controls mechanical properties effectively such as the spring constants and damping coefficients of the seat cushion by using an optimized algorithm that comprises vibration analysis and an optimization method. To estimate an efficient optimized algorithm, we investigate reduction rates of the vertical vibrations on the head using a vibration analysis based on a model for the seat-occupant system when the each cushion that control the mechanical properties are changed. From the results, it is shown that relationships between the reduction rates and the mechanical properties of the each seat cushion optimized at frequency band. In conclusion, the effective optimized algorithm using these relationships enable to reduce the vertical vibrations on the head while reducing the number of seat cushion control.

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In the oil-hydraulic circuit for the winch such as crane, the counter balance valve is used for putting a brake on the actuator. However, the oil-hydraulic circuit including the counter balance valve is instable, it is generally known to cause the oscillatory phenomenon easily. To provide stabilization of the counter balance valve, the damping of it is more effective in practice, however, it makes the response of the counter balance valve worse. Therefore the stability of the counter balance valve is developed on this study. At first, analysis model of the oil-hydraulic circuit for the winch including the counter balance valve is made and analysis result and experiment result are compared. Next, the stability of the counter balance valve is developed when the pattern of the variability orifice or annular clearance orifice of the counter balance valve is changed. In the consequence, it is approved that optimization of the damping of the counter balance valve provides stability and responsiveness of counter balance valve on a higher level.

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In design of tracked vehicles that run on non-pavement road or soft ground, it is important to analyze the interaction between a machine and soil. In vehicles with crawler such as bulldozer and loading shovel, for the decrease of examination frequency and the improvement of performance the interaction analysis is done. When the crawler vehicle runs, two or more teeth stick in the soil, which causes various factors such as compression and shear action and so on. These considered, it takes huge time to analyze the behavior of the soil and the crawler. So, up to now, the model with high analytical accuracy has not been established. Recently, the technique of distinct element method (DEM) was invented as computer technology develops. DEM is the technique that, regarding the soil as a large particle, we examine the motion of each particle based on the motion equations. As a result, analytical time was greatly shortened, and we came to represent the behavior of the soil. However, we could not make high accurate modeling of the soil and the crawler yet. So, I aim at further shortening of analytical time to make the higher accurate model. Therefore, I work on parallel of computer handling and shortening of analytical area of the soil. Success of this research has possibility to decide the crawler's shape which has the highest thrust.

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The carbon dioxide emissions can be reduced by half, if fixed-route buses are operated by electric buses in order to prevent the global warming. In addition, the emissions of greenhouse effect gases can be eliminated, if the buses are charged using electric power generated from green energy sources such as solar energy source and wind energy source. However, the weight of storage equipment mounting the electric bus is problem. To realize the zero-emission condition, we proposed the electric bus system charged at every bus stop using solar energy. This system can effectively utilize the widely-distributed and low-density solar energy sources because bus stops generating the clean electric power were widely-distributed in the city, and the weight of the proposed bus can be reduced because the bus requires only the charge of energy running to next bus stop. To minimize the weight of the storage device, a simulator is necessary to calculate the energy consumed in running between bus stops in each route. In this study, the simulator for the single passenger electric vehicle was proposed, and the method for identifying the parameters from acceleration tests, free running tests and deceleration tests with regeneration was established. Then, the effectiveness was confirmed by experiments, namely, the consumption energy and the velocity change could be almost exactly estimated from the throttle position.

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Spacecrafts are launched to space with locked up inside fairing which is top of rocket. When rocket are launched, mounted spacecrafts are under inclement mechanical environment and various mixed mechanical environment act spacecrafts should be designed to withstand such mixed environment and are tested and estimated as each environment. In this paper, we focus on environment of acoustic load of spacecrafts and analysis response of acoustic vibration of spacecrafts by using FEA-SEA combined method.

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In a coupled structural-acoustic system which has a box structure and interior air the position of a defect included in the structure is identified by using the frequency response of sound pressure level in the interior sound field. For the analysis of coupled structural-acoustic system Finite Element Method (FEM) is utilized. The box including a defect is excited by dynamical load and the frequency response of the interior sound are learned by Self-organizing Maps (SOM) as an input vector and the maps is drawn in the 2-dimensional plane. The frequency response for the model whose defect position is not known is given to the trained maps, and the identification is carried out. As a result the good accuracy of the identification is obtained. Furthermore, it is confirmed that the identification by SOM has better accuracy than by the other neural network such as LVQ (Learning Vector Qantization) or BNN (Back Propagation Neural Network).

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In this report, the improvement of the computation algorithm is tried aiming at a further performance gain of the SA/GA hybrid optimization method. In the problem of treating by the previous method, the square lattice is applied to the design space, and all nodes of the search individual can exist only on the one grid point. Therefore the shape of the individual generated becomes minute when the width of the grating space (width of the mesh) is narrow. On the other hand, it becomes difficult to settle to the Pareto optimum solution because the total of the solution that can be generated becomes huge and localized solution increases. Then, the method, that of widely setting width of mesh at early stage of calculation and narrowing moving range of node and width of mesh gradually, is newly introduced as measures of this problem. It was confirmed to obtain the Pareto optimum solution efficiently evading stagnating in the localized solution by such the operation.

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A hybrid optimization method using simulated annealing (SA) and a genetic algorithm (GA) developed in a previous study is improved in order to achieve high computational performance. The previous method, in which the genetic operations for generating initial search solutions of the next generation are introduced into the computation process of multi-point SA, can efficiently and globally compute Pareto-oplimal solutions, as compared to SA using a re-annealing method. However, a large number of Pareto-optimal solutions exceeding the acceptable amount of computer memory may be obtained. In the proposed method, in order to effectively store Pareto-optimal solutions in computer memory, all obtained solutions are classified according to topology type, and those that should be stored are selected from each topology group. In addition, selection methods based on four criteria are newly proposed in order to improve the convergence of solutions and to maintain their diversity. The proposed SA/GA hybrid algorithm for simultaneous optimization of the topology and geometry of a two-dimensional framed structure is applied to a two-objective optimization problem of minimizing the total weight and maximizing the first natural frequency under displacement and stress constraints. The validity of the proposed methods is confirmed through performance evaluation based on the Wilcoxon rank-sum test.

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The present study proposes a multi-objective optimization method to progress the mechanical property and minimizing the production cost for the fibrous composite plate with curvilinear fibers. The production cost is represented by the average curvature of the curvilinear fibers. Curvilinear fiber shapes are defined by the projections of contour lines for a cubic polynomial surface, and design variables are defined by the coefficients of the polynomial. Stresses and fundamental frequencies of the plate are calculated by a finite element code with isoparametric 8-node rectangular elements. An improved non-dominated sorting genetic algorithm (NSGA-II) based on the non-dominated sorting and crowded distance metric sorting is used as an optimizer with a mutation whose probability is controlled to maintain the variety of individuals and to keep searching ability strong. The numerical results showed that the present optimization method resulted in the widely distributed Pareto-optimum front ranging from parallel fibers to largely curved fibers.

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Though the rolling ball bearing greatly contributes to decrease the friction energy of the machine movement, we require the development of lower friction torque technology of ball bearing to achieve more efficient machine. Especially, the fluid resistance makes a important role when the ball bearing is soaked in lubricant.Estimation of the los of torque by the fluid resistance brings the reduction in the design cost. Therefore, in our research, it aims to develop the simulation technology of the fluid resistance by the ALE (Arbitrary Lagrangian and Eulerian) Finite Element Method. As the first step, we have established the simulation technology of movement analysis for the only ball bearing. In this report, we did the movement analysis numerical simulation of the ball bearing that considered the contact ellipse and EHL (Elastohydrodynamic Lubrication Theory).

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Packaging is essential to most kinds of industries. The basic part of the vertical form, fill and seal packaging machine is the forming collar. The forming collar provides the shape over which packaging film is smoothly formed into a cylindrical shape at high speed. Describing the forming collar geometry and hence its design is, however, remarkably difficult. And performance assessment for designing correct forming collar is not exited. This paper presents, for the first time, a method for the assessment by calculating the stress of the film on the geometry of the collar. Developable surface and non-developable surface are discriminated with this created method. And accuracy of this method is confirmed to be put to practical usage. Attention of this method is mesh size of the Finite Elements Method.

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Now, many products are packaged, like foods, medicines, and other groceries. Products like snacks are packaged by package machines. Forming collar, which is a part of the package machine, is very useful to make machine space-saving design and increase in packaging speed. But the current design method has problems in productivity and reliability, because it is based on traditional experiences and trial and error. So we used finite element method to design collar shape. This method could calculate shapes which could minimize the strain energy. Therefore it is thought to be useful to design collar shapes which create few wrinkles. Then, we show the relation between wrinkles, scratches and bending when passing through the forming collar.

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The noise of vehicles such as exhaust noise has become a important problem in modern society. Noise is uncomfortable for human beings and it is one of the seven typical pollution defined in the social law. The noise of frequencies less than lOOHz exerts bad influence to human body. A truss core panel proposed in this study is excellent in the interception, absorbing and radiation of noise. So, in this study the experimental research and simulation on the interception performance of a truss core panel which has high strength, high rigidity and low cost is carried out.

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This work illustrates the new method to manufacture the 3D shaped honeycomb cores. In usual methods, 3D honeycombs such as tapered or bended shaped cores require the difficult and high-cost processing, but this new method enables us to make arbitrary shaped honeycomb directory. In this paper, the basic concept of origami honeycombs is introduced firstly. They are made from single flat sheets with periodical slits like origami. Next, three types of simple 3D shaped honeycombs; tapered core, convex-curve core, nonconvex-curve cores are presented. These modified models are made by changing the folding lines and slits patterns of basic model. Finally, samples for these 3D shaped origami honeycombs are made by using the composite material.

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It is available, for the garbage assembling issue of the disposed empty PET bottles, that PET bottle could be axially folded up easily by both hands. Then, based on the geometrical theory of cylindrical Origami proposed by Nojima, we made some kinds of CAD model of PET bottle with regular folding lines in circular direction and evaluated the function of folding up for axial compressive loading by CAE. Two main useful results are obtained as follows. One is that the empty PET bottle with the configuration of inclined main folding lines could be folded up by hands. The second is that the PET bottle in full, with the configuration above mentioned, could have the stiffness necessary for keeping in a pile of bottles' case and vending machine by the effect of increased internal pressure which is loaded on the folding surface of the bottle wall.

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The alveolus is a structural and functional unit of the lung. The human lung consists of several hundred million alveoli which are arranged so as to participate in ventilation and entirely fill the lung space. I presented a computational 4D alveolar model and its expression by Origami in the "Dynamcs and Design Conference 2010. In this conference, I present a space-filling branching alveolar duct model and its Origami expression. Origami is thought to be a suitable tool for investigation and education in the biomedical field.

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The traditional origami crease has been a straight line. In the 1970's, however, David Huffman began to investigate the possibilities of curved crease. The model made with curved crease is called curved origami and recently some origami artists begin to work with curved folds. Though their works are superior in design, relationship between traditional origami and curved origami isn't clear. In this paper we show the curved origami mathematically and application to the manufacturing.

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Two kinds of origami models are presented by using a technique called rigid origami. The first model relates to an inversion of fronf'back surfaces by using a prescribed curved fold line, which brings a change of shape from conical plane to circular tube. The second relates to an effective folding method of circular tubes and conical shell. The former is modeled with the development of metal tool for vertical form-fill-seal machine under consideration.

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The influence of wave propagation in a body on the measurement of dynamic force by an accelerometer was investigated. Experiments were carried out in such a way to set up accelerometer on the side of a long Hopkinson bar, with its length varied, and strike an elastic bar of the same size against Hopkinson bar. It was revealed that the measurement of the dynamic force is possible only when a buffer material is set at the tip of the bar, and the bar acted as rigid body while the collision. Furthermore, available condition of the accelerometer was investigated through a collision experiment by knocking a load cell with a weight accompanied by the accelerometer.

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The first author has claimed that the sensitivity of the multi-axis inertia sensors in the dynamic state be expressed by a matrix as long as we are loyal to the mathematics and the physics. The claim was verified by experiment carried out using laser interferometry and the shaker with 3 DOR However, the issue remains whether the claim and the experimental data can be regarded as the general measurement technique. The second report presents the affirmative answer to this problem by showing the results of the comparison measurement experiment carried out by Prof. Tsuchiya, Kyoto University and Vectordynamics Corporation. The air-cooled three-axis shaker with 3 DOF is set up in Kyoto and the water-cooled three-axis shaker with 6DOF is set up in Tsukuba. The three-axis semiconductor accelerometer Colibrys SF3000L was used in Kyoto and Tsukuba. Three one-axis accelerometers are installed in the mechanical mount inside SF3000L. 9 components of the sensitivity matrix were measured. The results agree within 1.7% in gain. Authors strongly believe that the generalization of the sensitivity matrix measurement is successful. This report presents the technical items to be developed for further accuracy enhancement.

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This paper proposes and describes a novel method of determining the non-orthogonality and misalignment of the three axis accelerometers in the dynamic state. The method requires neither the three-axis reference accelerometer with the highest orthogonality and the least misalignment nor the optical instrument and the shaker with the input angle adjustment. The orthogonality and the misalignment are expressed by the components in the sensitivity matrix. The method utilizes two three-axis accelerometers, one as a target and the other as a reference. The measurement is carried out at the two different relative positions of the two accelerometers. The experimental verification was carried out using two IMUs with five DOF and a shaker with six DOF up to 70 Hz. The orthogonality and the misalignment become a complex number as the frequency of the input acceleration is increased.

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When elevators travel at high speed, horizontal vibrations of the car tend to be set up by guide rail deformation. Therefore, it is important to identify the deformation accurately to improve ride quality. In this paper, we discuss a method for estimating the rail deformation by an inverse transfer function and operational acceleration data. The acceleration data indicates the vibration caused by both the rail deformation and external forces acting on the car, that is, the rope sway and wind pressure excite the car directly when it is moving by a counter weight. To identify the rail deformation from these data accurately, we propose an elevator model that has guide levers and a car. Moreover, the estimation error occurs when accelerometers are installed inaccurately. To avoid this error, the weighting function based on the modal vector is also introduced. The validity of the method is shown by the simulations and experiments.

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This paper proposes a noncontact vibration testing system for a rotating disk based on an impulse response excited by a laser ablation. High power YAG pulse laser is used in this system for producing an ideal impulse force on structural surface without contact. The contactless vibration testing system is composed of a YAG laser, laser Doppler vibrometer and spectrum analyzer. This system makes it possible to measure vibration characteristics of structures under operation, such as vibration measurement of a rotating disk. The effectiveness of this system is confirmed by experimental and theoretical analysis. In this paper, a platter of hard disk drive is employed as an experimental object. Vibration characteristics of a rotating and non-rotating platter are measured and compared with the results of theoretical analysis.

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When agricultural machines are operated on pavements, the vibration and noise caused by the interaction between the tire lugs and the road surface are inevitable. In a conventional study, it is considered that the dynamic behavior of a rolling agricultural tire is influenced by the vibration characteristics of the tire. Resonance occurs when the lug excitation frequency of the tire, which is defined as the lug number multiplied by the number of revolutions of the tire, becomes equal to the natural frequency of the tire. In other words, the rolling tire shows large vibrations in the direction of the natural mode corresponding to the natural frequency of the tire. However, the vibration mode of the rolling tire in resonance state has not yet been clarified. In this study, it is confirmed that the dynamic behavior of the rolling tire can be evaluated by performing sound pressure measurements at near field using microphones. Further, the vibration mode in the resonance state is identified by performing simultaneous measurements of the sound pressure, and it is confirmed that the vibration mode corresponds to the natural mode of the tire.

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In this paper, a method employing PARAFAC (Parallel Factor Analysis) is proposed to filter out noise from the signal of the FBG (Fiber Bragg Grating) sensor based on the AWG (Arrayed Waveguide Grating). The experimental results show that the performance of the proposed method is similar to that of the conventional signal-averaging method, which identifies the signal in the case of multiple measurements. PARAFAC is one of several decomposition methods for three-way data and the decomposition is unique without additional orthogonality or independence constraints. When Bragg wavelength of the FBG varies upon receiving an ultrasonic wave, the outputs of two adjacent AWG ports fluctuate in anti-phase. We use wavelet transform to pre-process the AWG ports data series, then the coefficients of the wavelet transform are decomposed by PARAFAC to trilinear components, which represent frequency, temporal, and phase profiles. The factor for which the ports fluctuate in anti-phase is chosen as the target signal and restored to three-way data. The performance of the proposing method is examined in experiments and its validity is shown.

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In order to increase the capacity of renewable energy in power systems, it is necessary to reduce power fluctuations. In this paper, the potential of gas engines (GEs) is evaluated by means of dynamic simulation. In this system, a hybrid generation system made up from GEs and photovoltaic cells (PV) supplies power to a large grid. Such a system is hoped. As a result of simulations, 9.9 kW GE is very useful to compensate PV power fluctuation. The efficient way using GEs to compensate scaled-up version of renewable energy is also discussed in this paper. In conclusion, the next three points are revealed to be effective. (1) Adding a larger scale GE to small scale GEs, (2) controlling preferentially the GE whose output variation speed is faster, and (3) decreasing lower limit of GE outputs.

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In order to prepare for the sales expansion of FCV (fuel-cell vehicle) around the comer, hydrogen stations are steadily increasing. We released a most suitably designed Coriolis flowmeter for hydrogen dispensers in 2005. Since then, the models have been adopted in many hydrogen stations of pressure levels, 35MPa and 70MPa and accumulating its quantity delivered for flow measurement, as well as contributing to R&D by relevant FCV makers. In a verification test by JHFC (Japan Hydrogen & Fuel Cell Demonstration Project) , the flowmeter achieved the target for 70MPa hydrogen dispensers of filling in a FCV's 5kg tank in 3 min. by improving the filling time and efficiency to the better. Further, safety functions have constantly been under consideration, resulting in to change the measuring tube material from Alloy C to SUSS 10S, which does not embrittle even when exposed to high pressure hydrogen gas. In this thesis, technical features of the flowmeter and results of the filling tests are introduced, and the improvement process up to now and future prospects are reported.

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