This study aims at designing a control system for an automotive active stabilizer in order to reduce the roll angle during cornering and suppress the rolling vibration on a rough road concerning the ride comfort. A full vehicle model which has a suspension system with the active stabilizer is formulated. The control system for the active stabilizer is designed for the full vehicle model using the linear quadratic control theory. It is verified that the active stabilizer controlled by the control system designed is effective for both the roll reduction and the improvement of the ride comfort, although the passive stabilizer is only effective for reduction of the roll angle during cornering but makes the ride comfort of the vehicle worse.

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Half ring structure is used for a stator vane of turbo-machinery. In order to exactly analyze the vibration response characteristics of a half ring structure, a whole model should be used, because the cyclic symmetry method cannot be applied for it. In the mechanical design, however, it is unpractical. In this paper, an efficient method for predicting the vibration response characteristics of a half ring structure is proposed. The vibration response characteristics of a half ring structure and a full ring structure are compared, using the formulation derived. The vibration response analysis for an actual steam turbine vane with a half ring structure is carried out to verify the validity of the method proposed here.

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This paper presents a computational method of such random vibration of the turbine blades using the multi-degree of freedom spectrum analysis. This computational method applied the cyclic symmetry method to the spectral analysis and enabled a large-scale calculation of the steam turbine blades. Also, the random vibration examination by a simple blade model was done, and the problems of the calculation condition were clarified. Both modal damping and random excitation PSD are most important factors of the calculation. The calculation results were corresponding to the measurements well, and the validity of the computational method was confirmed.

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The turbine generator requires sufficient reliability as a major component of the power plant. For longer blades, however, the lower natural frequency requires that the design of the shaft and blade takes into account the coupling of the blade vibration mode, nodal diameter k=0 and k=1 with the vibration of the shaft. The present work analyzes the coupling of the tilting motion of the shaft with the out-of-plane vibration of the blade within k=1 modes. At a rotational speed Ω_1=|ω_s-ω_b|, the resonance of the blades had a relatively big amplitude. The resonance in blade vibration at Ω_1=|ω_s-ω_b| was experimentally confirmed.

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There are many harmonic components in the electromagnetic force caused by motors. The harmonic components induce the structural vibration and noise. In this paper, electromagnetic vibration and noise from motor with off-centered rotor are discussed comparing with normal motor in numerical analysis. As a result, harmonic components are increased and the average of vibration is about 1.05 times above comparing with those of normal motor.

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This study aims at predicting the stability threshold speed of the horizontal rigid rotor supported in bump foil journal bearings, by using two model bearings, one of which corresponds to the bearing with an excessive static friction between the top and the bump foils and the other to the bearing without the friction. It is found from the modified stability charts that some of the design variables of the bearing, such as rigidity, attached angle and angular extent of top foil and stiffness of bump foil, have a perceivable effect on the speed of the rotor-bearing system.

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In this study we make clear dynamic characteristics of a hydrostatic gas journal bearing in consideration of hydrodynamic effect. Trends of diagonal terms of stiffness matrix K_<xx> and damping matrix B_<xx> mainly depend on a feeding parameter Γ and don't so depend on a bearing number Λ which corresponds to rotating speed Ω. On the other hand, trend of cross terms of stiffness matrix K_<xy> and damping matrix B_<xy> mainly depend on Λ. We can stabilize a rotor supported with the hydrostatic gas journal bearing by choosing the optimum feeding parameter Γ in order to increase the stiffness K_<xx> and the daming B_<xx>.

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Many rotors are supported by an oil film bearing which has high stiffness. Since the gap of an oil bearing is very small, we must suppress vibration as much as possible to prevent metal contact by an oil membrane break. Therefore the damping ratio is an important index to use when evaluating the rotor system stability. However it is difficult to identify the damping ratio under various conditions. In this paper, we introduce a new method using the modal open loop transfer function. This method provides a more accurate Q-value and can help to identify the damping ratio by considering only the mode which we want to measure. We evaluate the damping ratio of the oil film bearing with a dynamic damper which is developed for suppression of oil whip instability.

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This paper deals with flexible rotor balancing methods. In addition to conventional modal balancing method using n or n+2 correction planes corresponding to n modes within operating speed range, we propose 2n correction planes using anisotropy of bearing stiffness for X and Y direction. And the new concept to evaluate balancing accuracy to direct comparison of unbalance distribution obtained by balancing calculation and given unbalance distribution. The proposed method was tested for model rotor having 5 correction planes. The results show the possibility to improve balancing accuracy using this method.

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The ball balancer has been used for the vibration suppression method in rotor system. It has a sperior characteristic that the vibration amplitude is reduced to zero by it at the rotational speed range higher than the major critical speed. However, the ball balancer may cause a self-excited vibration when the balls rotate in the disk, and this self-excited vibration results in the large amplitude vibration. In this paper, the vibration suppression method for such vibration problems due to the ball balancer is investigated. Both the linear and nonlinear spring characteristic of the shaft are controlled by changing the axial position of the repulsive magnetic bearing (RMB). The influence of nonlinearity and the vibration suppression effect of the control parameters are investigated numerically and theoretically. The significant reduction of the occurrence region of theself-excited vibration is achieved by controlling the axial position of RMB appropriately.

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Effects of an automatic ball balancer to a rotor with nonlinear spring characteristics are investigated. Similar to the case of a rotor with linear spring characteristics, the rotor is balanced automatically in the higher speed side and the amplitude becomes zero, however, amplitudes in the lower speed side increase and almost periodic motions appear in the neighborhood of the major 9, critical speed. A subharmonic resonance and a summed-and-differential harmonic resonance are eliminated completely by a ball balancer if the masses of balls are large in comparison with the rotor unbalance.

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Vibration characteristics of a rotor with a ball balancer are investigated. It is shown that , when balls more than 3 are installed, infinite number of solution for the ball positions are obtained although the automatic balancing is attained. When the rotor is accelerated, the balls rotate in the rotor with satisfying the balancing condition. The almost periodic motion which is the major defect of the ball balancer can be decreased by making partitions in the rotor. When more than 3 partitions are used, the rotor is balanced for any position of the unbalance. When 2 partitions are used, the rotor is not balanced for some range of unbalance.

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Free coning motion of axi-symmetric spinning bodies around their fixed angular momentum vectors, called free precession, have already been explaned using body/space cones in the 19th century. It is very easy to describe their motion of the radial angular momentum vectors as circles on a horizontal complex plane, if the total angular momentum vectors are large enough and nearly vertical. As a result, a linearized equation of motion of spinning tops including both horizontal components of frictional torques and the gravitational one could be derived easily. As an example, trochoid model of horizontally suspended spinning tops is shown using a rolling wheel and a rail.

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Experimental studies were conducted to clarify unexpected vibrations which occur in a cylindrical filter made of unwaven cloth. The cloth is made of polypropylene which catches dust from an air conditioner by static electricity. Two types of filters with 1.8m and 3.7m length were used, both of their diameters are 45cm and the thickness is 1.08mm. The filter is hung from the top at intervals of 50cm. The velocity distribution of air flow from a duct and the response frequency and amplitude of the filter were measured. We found that the flow was able to rectifize, when attached honeycomb panel to the duct. By varying the length of the filter and honeycomb panel's cell size, the vibration shape in circumferential direction varies.

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This research presents a semi-active method for vibration control of CFRP composite structures with piezoelectric transducers. Using a vibration control system that contains piezoelectrics, inductor and switch devices, vibration suppression is possible without supplying outer electric energy to the piezoelectric system. Numerical simulation and experiment of vibration control of a CFRP cantilevered beam is performed to verify the effectiveness of a semi-active method. The present control method is also compared with an active vibration control method based on LQR method.

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It is useful for light saving design to substitute composite materials for steel material with mechanical applications. This report shows vibration mode identification method for the door panel which is widely used in automobile vehicle body. Composite material (fiber reinforced plastics: FRP) have the excellent possibility of light saving design for the demand of changing in structural stiffness with tailoring the fiber-direction or stack-sequences of laminated composite materials. In this study the first, the influence of lamination condition for the natural modes of curved panels are calculated by the Ritz vibration analysis method. The next, the identification study for determination of the approximate natural modes of the laminated panels in reference to the modal testing results is discussed.

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This study presents experimental results on chaotic vibrations of a shallow cylindrical shell-panel with clamped and simply-supported boundaries. Both opposite sides of rectangular boundaries are clamped by blocks and the other opposite sides are simply supported by flexible films. First, to find fundamental properties of the shell-panel, the linear natural frequencies and the characteristics of restoring force of the shell-panel are measured. Then, the shell-panel is excited with lateral periodic acceleration. In typical ranges of the exciting frequency, irregular non-periodic responses are generated. These responses are examined with the Fourier spectra, the principal component analysis, the maximum Lyapnov exponents and the Poincare projections. It is found that the predominant chaotic responses are generated from internal resonance condition of one to two and of one to three between the lower-modes of vibration of the shell-panel.

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The purpose of a present investigation is to clarify the vibration characteristic of the piezoelectric vibrator which has been applied in a small pump. This piezoelectric vibrator is coated with silicon rubber, and is influenced by a fluid element of pump chamber. Experiments and FEM analysis were carried out to investigate the influence of both water and air, which were hermetically sealed in the pump chamber. As a result, the resonance frequencies of piezoelectric vibrator could be simulated approximately by FEM analysis. In the case of the water, it was clear that the resonance frequencies of piezoelectric vibrator became lower and decreased the amplitude displacement.

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This report presents an analytical method to investigate the three-dimensional elastic vibration problems on a railway carbody. The carbody is modeled as a simply-supported non-circular cylindrical shell without end plates. The model has an advantage of the matrix size for calculation. Therefore we have applied this model to simulate the effect of the rigidity of the connecting part between roof and side panel. As a result, it is found that amplitude ratio of floor to roof can be reduced when we set the rigidity of the connecting part between roof and side panels to higher value. And it is also found that the natural frequencies become higher at the same parameter changing.

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The fundamental frequencies of symmetrically laminated composite plates with irregular shapes are maximized with respect to fiber orientation angles in the layers. Based on the first-order shear deformation theory (FSDT), the eight-node quadrilateral isoparametric element is developed, and a layerwise optimization (LO) approach is extended to be combined with this finite element. In numerical examples, trapezoidal plates with different side ratios and square plates with different position of circular holes are analyzed for six different boundary conditions. Finally, the significant effects of different shapes on the maximized fundamental frequencies and the best fiber orientation are demonstrated.

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A method of analysis is presented for determining the free vibration frequencies of twisted laminated panels under general edge conditions, and is implemented in a layerwise optimization (LO) scheme to determine the optimum fiber orientation angles for the maximum fundamental frequency. Based on the classical lamination theory, a method of Ritz is used to derive a frequency equation where in the displacement functions are modified to accommodate arbitrary sets of edge conditions for both in-plane and out-of-plane motions. In numerical examples, natural frequencies and mode shapes are presented for a wide range of geometric parameters, and the maximum fundamental frequencies are determined by the LO design approach.

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This paper studies the optimization for inner rib's thickness of the shell structure of aluminum allow hollow extrusion by using genetic algorithm. In the optimization, total mass of the structure is minimized under the constraint conditions with respect to maximum deformations of the structure. The deformation of the structure is evaluated numerically by using the finite element analysis developed for two-dimensional elasticity in the present study. In numerical calculations optimal design solutions are obtained for the structures by specifying the allowable maximum deflections of the structure, and the effect of the rib's thickness is studied from the numerical results obtained.

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It is desirable to optimize the fiber orientation angles to maximize the fundamental frequencies of the fiber reinforced plastic plates. The optimization is studied here by using the experimental design for nonlinear problems, and it turned out that significantly less number of calculations is necessary as compared to other methods, such as a layerwise optimization approach (LOA). The numerical examples show that assumption of appropriate level values is efficient to obtain the optimum frequency in the vibration problem.

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In previous studies, it was shown that neglecting the nonlinearity of sloshing significantly underestimates the magnitude of stresses in the floating roof. This underestimation becomes more significant when the internal resonance is caused. In this paper, influence of the liquid depth on the stresses is investigated. Numerical results show that the stresses become large due to the internal resonance when the ratio of the liquid depth to the tank radius increases. It is illustrated that the internal resonance may be caused by an actual earthquake ground motion as well as sinusoidal excitation.

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The floating roofs are widely used to prevent evaporation of content in the large oil storage tanks. The 2003 Tokachi-Oki earthquake caused severe damage to the floating roofs due to liquid sloshing. The structural integrity of the floating roofs for the sloshing is urgent issue to establish in the petrochemical and oil refining industries. This paper presents the sloshing characteristics of single deck floating roofs in cylindrical storage tanks. The hydrodynamic coupling of fluid and floating roof is taken into consideration in the axisymmetric finite element analysis. It is assumed that the fluid is incompressible and inviscid, and the roof is linear elastic while the sidewall and the bottom are rigid. The basic vibration characteristics, natural periods and vibration modes, of the floating roof due to the sloshing are investigated. These will give engineers important information on the floating roof design.

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Flow-induced vibration occurs in the structures subjected to narrow annular flow such as elastic beam in the narrow annular flow. Once the vibration occurs, the vibration becomes larger. In this paper, active control of the vibration of the axisymmetric elastic beam subjected to narrow annular flow is investigated. The fluid-structure coupled equations based on the Euler-Bernoulli type partial differential equation and Navier-Stokes equation are derived including control terms. In this paper, setting the air-pressured actuator in the gap, the coupled system is controlled. Applying the optimal control law to the coupled system, the unstable behavior is stabilized. The simulation studies are performed to investigate the efficiency of the proposed control method and the effect of the position of actuator on control performance.

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This paper describes the active feedback control of leakage-flow-induced vibration in translational one-degree-of-freedom system. In this paper, suppression of the leakage-flow-induced vibration by the active feedback control technique is demonstrated experimentally and theoretically. The leakage-flow-induced vibration is suppressed by the active feedback to the moving of the baffle plate at the inlet or outlet of the passage. The vibration is stabilized by the phase progress between displacement of a baffle plate and displacement of a rigid body at inlet and the phase lag at outlet. The critical velocity of calculation result accorded with an experiment result qualitatively.

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Recently, there are so many researches and developments in order to design micro machines that inspect and operate in blood vessels. The vessel wall influences fluid flow that affects the motion of micro machines. It is important to clarify the fluid-solid interaction in case of small clearance between a micro machine and the vessel wall to design micro machines with enough reliability. This research investigates the motion of a sphere and fluid flow in a narrow tube under the constant external force of gravity acceleration parallel to the pipe axis.

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The FDC (Flow Dynamics Conveyer) has been often used in power plants and iron works because of superiority in quiet compared with a roller type conveyer and it is excellent in a low noise and low power. The FDC consists of a trough and a belt, and the air is supplied from a lot of holes provided on the trough. However, large vibrations occur when the flow rate becomes the certain value. This abnormal vibration is defined to be self-excited vibration caused by leakage flow induced vibration here. In this study, as the first step, the theoretical model of non tapered clearance flow passage is assumed and the natural frequency is obtained. On that basis, experiments are performed and the validity of the theory is examined. As the second step, in case of tapered clearance flow passage, the concentrated load is added to the belt, and the effects of the belt deformation, the flow rate and the added loads on the clearance flow are examined. the generation mechanism of the abnormal vibration is considered. As a result, it was clarified that the presented theory was useful in case of non tapered clearance and the generation mechanism of the self-excited vibration was the phase shift due to the change of the parameters.

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This paper deals with vibration intensity control of the plate on the hypothsis that only two mode is excited for the 2-dimension non-contact transportation using ultrasonic wave levitation. First, the relation between vibration intensity of the beam and phase difference of the external forces installed into the both ends of the beam is considered from a viewpoint of numerical analyses. This is followed by the calculation of the intensity flow pattern of the plate. Finally, it is shown that vibration intensity of the plate is controlled on the hypothsis that only two modes are dominant in the vibraiton field.

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The outbreak mechanism of self-excited oscillation of the wire electrode due to corona discharge has not been necessarily given yet. In this paper, the experiment that is focused on the effect of ionic flow field was conducted. Measurement aiming to figure out the relationship between flow velocity and applied voltage was performed with PIV. Then to investigate the influence of heating current to the ionic flow, temperature of the wire and its effect on the corona wind was examined. As the result, natural convection does not change flow field while increment of discgarge current enhance corona wind whitch generates causes of oscillation.

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In order to design the toilet chair as a xcretuing support sysytm, sensory evaluation tests have been prformd for the various hight of toilet chiares. As a results, the confortable feel of sitting chair obtain at wide area contact with tigh and hip. Toilet operation using excretion support equipment showed Omore confortable feeling at the case of the more low hight of toilet chiar. On the other hand, sensory evaluation factor for the easiness to stand up motion from the tilet chair showed more confortable feeling at the case of the more high toilet chair.

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Because the In-wheel motor of a direct drive is adopted as a system that can support it for a long time as compactly as possible, and the examination of the power system including the resurrection of the walking energy was done as a development research into the walking support machine, it reports.

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A new power assist suit consisting of shoulders, arms, a back, a waist, hips and legs units was developed. For increasing squatting down movement, the movable angle of hip unit was increased using ball joints. The validity of the improved hip and leg unit was proved experimentally.

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This paper proposes a method to prevent contracture, facilitating rehabilitation treatment of patients with paralysis, even staying at their own house. In order to realize it, an actuator which is installed directly to the human body and can perform natural movement is developed. The aim of this actuator is to have no mechanical rotational center and still be able to realize a one-rod shaped structure is, Hence, a Variable Trajectory Rotary Actuator (Vat-Rotary hereafter) is proposed and its design is explained.

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This paper discusses an Internet-based tele-rehabilitation system with Single-Master and Mufti-Slaves, which aims to achieve the situation where multiple stay-home patients in scattered places can share rehabilitation instruction from one physical therapist. After the introduction of whole system's concept, 'Passive-Active Shift' rehabilitation is proposed considering the varied symptom of different patients. Then after introduction of master/slave system's designing, for passive rehabilitation which is carried through internet-based bilateral teleoperation system by therapist who is necessary, novel control architecture to ensure the stability of tele-rehabilitation system with time delay is proposed.

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We have studied dynamics of magnetic brushes in the two-component development system of electrophotography by the numerical simulation with an improved Distinct Element Method (DEM) and experimental observation with a high-speed microscope camera. Two-dimensional magnetic field was calculated by superposing measured discrete magnetic flux densities on a development sleeve. It has been calculated and observed that magnetic brushes grow up in the development area inclining in parallel in the direction of the magnetic field and they are crushed by a photoreceptor drum. It has been evaluated that although the total pressure applied to the photoreceptor is almost irrelevant to the diameter of carrier particles, differential force applied by individual chain is dense and small with small particles but rough and large with large particles. This suggests that small carrier particles are preferable to prevent disturbance of developed toner particles on the photoreceptor.

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This research deals with dynamics of dielectric elastomer under a high electric field applied to the elastomer. Taking advantage of this phenomenon, a flexible actuator like artificial muscles is expectable. A bending actuator of cantilever type was considered and the governing equation was derived. From this governing equation, eigenmodes and eigenfrequencies were obtained by using static equilibrium solutions, both with and without D.C. voltage. Under the condition of A.C. voltage applied, a frequency-response curve was obtained by using the method of harmonic balance.

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It is desirable to investigate changes in vibration characteristics of pedestrian bridges to evaluate the seismic performance of corroded pedestrian bridges. This paper presents evaluation results of vibration characteristics of corroded pedestrian bridge by Kugenuma seaside. First, traffic vibration tests, free vibration tests and excitation tests using a small vibrator were performed to investigate the vibration characteristics of the pedestrian bridge. Next, eigenvalue analysis using a beam model of the pedestrian bridge was performed, and the analytical results were compared with the vibration test results. From these results, effects of structural corrosion on the vibration characteristics of the pedestrian bridge were clarified.

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This paper addresses the relation between our proposed modal cluster decomposition and the lumped mass modeling method which is proposed by Seto. Firstly, a realization method of the modal cluster decomposition is expanded using sensor placement together with the design of sensor gains for each sensor. Secondly, it is proved that the realization condition of modal cluster decomposition is same as the diagonalization condition of mass matrix in lumped mass modeling method. Finally, this paper numerically demonstrates its applicability to the lumped mass modeling of a cantilever beam.

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In order to control vibrations of machinery, it is very important to grasp the dynamics characteristic of the systems. Modal analysis is widely used as a basic technology for machine design. Various methods to identify the modal parameters of structures by the vibration test are proposed. Recently, the time domain subspace method has been researched actively. However, it is difficult to overview dynamic properties of structures from time domain data. In this paper, the frequency domain subspace algorithm is employed to identify modal parameters. Two kinds of algorithms are compared in numerical examples. Finally, the identification procedure is applied to a steel plate.

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This paper proposes to utilize the multi-way decomposition method PARAFAC for analysis on lateral vibration of a simply supported beam. First we use wavelet transform to pre-process the data series measured by five sensors, then the coefficients of the wavelet transform are decomposed by PARAFAC to trilinear components, which represent frequency, temporal, and spatial profiles. We easily obtain natural frequencies and modal shapes. Results of numerical calculations show the validity of this method.

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Transfer Path Analysis (TPA) is a key technology for tackling with the noise and vibration problems, and the precision of the input identification influences the result of contribution analysis. This paper presents a new approach to improve the estimation accuracy of the input by the conventional approach Matrix Inversion Method. To avoid the inversion of the ill-conditioned matrix, the apparent-mass matrix (force/acceleration FRF matrix) is estimated in a vibration test. Finally, it is shown that the identification accuracy by the apparent-mass matrix approach is superior to the matrix inversion method.

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Structural topology optimization has been applied to the various problems, and accepted into industrial as a useful tool. But, in some case, numerical instabilities such as checkerboard patterns appear. For the problem, smoothing method called H^1 gradient method has been proposed. In this paper, applying H^1 gradient method to maximizing eigenvalue problem, it is shown that the smooth topology can be obtained. And, showing difficulty of applying the topology optimization to vibration problem, the new approach to maximize eigenvalue considering static stiffness is proposed.

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This paper derives a modal expansion of structural intensity for longitudinal and bending vibration on beams. The expansion is expressed by the superposition of modal terms expressed by the product of weight coefficients and cross-modal functions. Cross-modal function is presented by the product of two modes with or without spatial derivatives. Numerical simulation is carried out in order to verify the modal expansion derived. The expansion is also applied to calculate the structural intensity on a beam with a branch in order to discuss the description by the cross-modal functions to change the intensity due to the branch attached.

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This paper describes a structural adjustment method for subsystems bringing desired coupling loss factors (CLF) in statistical energy analysis (SEA). We had developed the structural design process based on the experimental SEA in order to reduce structure-borne sound in machinery. The process in a few days identifies which CLF should be changed for reducing noise radiated from machinery. The adjustment method is implemented using the finite element method and optimization algorithms. The finite element model represents a part of a whole system and comprises a junction and the neighboring SEA subsystems associated with the CLF to be changed. In this paper, the proposed method for the structural adjustment was demonstrated. The adjustment method was shown to work well in identifying a structural design of the subsystems which achieves the desired CLF.

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The objective of this research is to investigate the vibration characteristic of the blade of a camera shutter unit. To clarify the vibration characteristic of the shutter blade is need to improve the sound quality and the performance of the shutter unit. The shutter blade is a thin plate part, which is combined four different shape narrow plates and two different length support arms. The forced vibration testing method on different component parts of shutter blade carries out measurements. Consequently, the vibration characteristic of the front blades and the rear blades doesn't change so much. The peak frequencies are almost same between two vibrating conditions that is the horizontal and vertical direction vibration condition. In only the vertical vibration condition, twisting vibration occurs in the constructed shutter blades.

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The structural analysis can reduce the time and the cost of the mobile device design. Especially, the drop impact response analysis is one of the most important analyses at the early design stage. Firstly, we focused on that the shape at the time of the drop is similar to the modal shape of mobile device, and we derived the drop impact response analysis, using modal analysis. And we found that the simple plate model can be used for this analysis model in substitution for a complicated model converted from CAD. At last, we found that our proposed method accuracy is almost same as finite element analysis by explicit method using complicated model.

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For this study, "Rigidity Test Car" have been designed and manufactured to investigate how non-structural members in the carbody influence on the rigidity and the vibration characteristics of a commuter type railway vehicle. Reinforcing beams, posts and joists, which are so designed as to be easily attached or removed, are installed to the ceiling, the side panels and the floor. Excitation tests have been performed, and the results have shown that the non-structural members, as well as the main (outer) body structures, have largely affected the natural frequencies, vibration shapes and response accelerations of the carbody. It is estimated by the FEM analysis that the mass of the reinforcing components can be reduced without changing natural frequencies and vibration shapes.

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Modal property estimation of railway vehicles by using the linear prediction model is studied in this paper. Determination of appropriate model order(order of prediction coefficients of ARX model) is especially discussed from the view of practical use. To employ average prediction errors for two different parts of analyzed data is proposed and their effectiveness to determine the model order is evaluated. The availability to apply the linear prediction model for MIMO (multiple-input multiple-output) problem is also described. It is shown that detailed modal characteristics can be identified using proposed method from measured data obtained from both of running test and stationary test.

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