researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Language：Japanese   Publisher：Japan Society of Mechanical Engineers  

Ultrasonic flaw detection and sizing are important issues for insuring structural reliability of industrial plants. While ultrasonic phased array technique is one of the most effective tools to visualize the flaws in the structural components, the spatial resolution enhancement of phased array image is still required to conduct more accurate ultrasonic testing. For this purpose, in this study, high spatial resolution phased array probe was designed by acoustic analysis by changing width, length, distance and total length of the phased array probe respectively. After that, the effectiveness of the designed phased array probe was investigated experimentally utilizing synthetic aperture focusing technique. However, the flaw image could not be visualized clearly because the lateral wave, back wall echo and high amplitude Rayleigh wave disturbed the received signal. Then the visualization image was reconstructed by removing these waves and the flaw image could be visualized clearly.

DOI： 10.1299/kikaia.76.398

Scopus

researchmap

Language：Japanese   Publisher：Japan Society of Mechanical Engineers  

Evaluation of fatigue strength under cyclic loading is one of the most basic issues for the design of engineering products. Fatigue limit of materials is usually evaluated by the fatigue test using some standard test piece. In addition, evaluation of fatigue limit of real parts of products is demanded nowadays in order to ensure the safety of engineering products from more practical viewpoint. However, fatigue limit evaluation of such real parts by usual testing methods costs too much to conduct in practice. To reduce the cost for fatigue limit evaluation, a newly developed technique utilizing the temperature rise due to energy dissipation under cyclic loading is paid attention recently. In this paper, this technique is applied to fatigue limit evaluation of notched specimen in order to verify its applicability. As a result, it is verified that the fatigue limit predicted by this technique coincides very well with that determined by usual fatigue testing method.

DOI： 10.1299/kikaia.76.410

Scopus

researchmap

Language：Japanese  

researchmap

DOI： 10.1299/kikaia.76.398

researchmap

DOI： 10.1299/kikaia.76.410

researchmap

DOI： 10.1299/kikaia.76.325

researchmap

researchmap

researchmap

DOI： 10.1299/kikaia.75.507

researchmap

researchmap

Language：Japanese   Publisher：Japan Society of Mechanical Engineers  

For guaranty of quality of the non-based adhesive sheet, one kind of adhesive used in flat panel display (FPD), damage of adhesive in a laminate process should be controlled to evaluate the interface strength. Standard examinations are not suitable for evaluating the interfacial strength because measured the peel force F includes other influences of peeling. In this paper, we developed Multi Axes-driven Peel method (MAP) to measure the peel force F from 30 to 180 degrees of the peel angle. The delamination energy and the energy dissipation were evaluated considering energy balance in steady state. This delamination energy dependency on the peel angle was discussed to observe the peel front. Then peel force in a laminate process can be obtained by the Y-type peeling test. The prediction of peel force in the Ypeel test using the delamination energy and energy dissipation measured by MAP were in good agreement with the experimental result.

DOI： 10.1299/kikaia.75.507

Scopus

researchmap

Language：Japanese  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

A computational procedure for analyzing the deformation and fracture of solid polymers is developed based on a molecular chain model. In the model, the polymer solid is represented by a network of nonlinear elastic chains. Cellular automata modeling is employed to generate the network of polymer chains. Van der Waals and viscous forces acting on the chains are taken into account and are approximated to act at the nodal points of the network. A stiffness equation is derived by employing the principle of virtual work, in which geometrical nonlinearity due to a large deformation is considered. Slippage and scission of chains are also taken into consideration. The effects of molecular weight distribution and molecular chain scission due to UV-degradation are discussed.

DOI： 10.1299/jsmea.49.503

Web of Science

researchmap

Language：English   Publisher：Trans Tech Publications Ltd  

The mechanical properties of polymers are strongly influenced by meso-scale (10-9∼10-3 m) structure such as entanglement, molecular weight distribution, orientation, etc. It is important to understand the relationship between the mechanical properties of polymeric material and meso-scale structure. Some studies related to the relationship have been made. However detail of the relationship is still unclear. Especially, the studies emphasize on entanglement and branch are few. This study aims to clear the role of entanglement and branch for mechanical properties by simulating the meso-scale structure using 3D network models. In the models, there are two structures considered. One of them has no branch, and, others have branch. Large strain deformation of network models is evolved via improved molecular dynamics analysis.

DOI： 10.4028/0-87849-989-x.983

Scopus

researchmap

researchmap

Language：Japanese  

DOI： 10.11396/jjsndi.55.635

CiNii Books

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society for Precision Engineering  

DOI： 10.2493/jjspe.72.9

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00317349915?from=CiNii

Language：English  

Ultrasonic flaw sizing is important issue for remaining life prediction of industrial plants. Time-of-Flight Diffraction (TOFD) method is recognized as one of the most accurate flaw sizing method. However, to measure the crack height accurately, the crack must be symmetrically placed between transmitter and receiver. When the crack do not exist such position, the B-scan is required for accurate crack sizing. By the way, if additional transmitter or reciever is added to the system, the crack location and height can be estimated without B-scan. In this study, we examined the 4 sensor TOFD method which utilizes two transmitters and two receivers. In the result, the crack location and height can be estimated by 4 sensor TOFD method. However, the estimation errors were large due to the low SN ratio of received signal. Then we applied the pulse compression technique to the 4 sensor TOFD method for improving SN ratio of received signal. In the result, the SN ratio was enhanced about 11 dB by the pulse compression. The average location on error is reduced from 2.49 mm to 1.13 mm, and the average depth estimation error is reduced from 0.28 mm to 0.21 mm. © 2006, The Japan Society of Mechanical Engineers. All rights reserved.

DOI： 10.1299/kikaia.72.2030

Scopus

researchmap

DOI： 10.1299/kikaia.72.2030

researchmap

DOI： 10.11396/jjsndi.55.635

researchmap

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

A computational procedure for analyzing deformation and fracture behavior of solid polymers is developed based on a molecular chain model. In the model, the polymer solid is reprenented by a network of non-linear elastic chains. Van der Waals force and viscous force acting on the chains are taken into account and are approximated to act at the node points of the network. The stiffness equation is derived by employing the principle of virtual work, in which geometrical non-linearity due to large deformation are considered. The chain slippage and the chain session are also taken into consideration. A cellular automaton modeling is introduced to generate the network of polymer chains. The effects of molecularweght distribution and molecular chain session due to ultra-violet degradation are discussed through numerical analysis.

DOI： 10.1299/kikaia.71.1333

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00262682815?from=CiNii

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

Thermoelastic stress analysis (TSA) is a non-contact and full-field type method of experimental stress analysis. Since TSA provides only the sum of the principal stresses, many studies have been carried out for developing techniques of stress separation. Unfortunately, most of the techniques developed hitherto are rather complicated and require much labor in practical application. Recently, the authors have developed a simple technique by utilizing the nonlinearity of the thermoelastic effect. In this technique, principal stresses are determined from two sets of temperature amplitude data measured under sinusoidal loadings having same amplitude but different mean values. However, the difference between temperature amplitudes obtained at different mean loadings is very small and, therefore, the result of stress separation becomes very noisy. In this paper, several smoothing techniques are applied to the temperature amplitude data in order to improve the accuracy of stress separation. It is found that some simple smoothing techniques are effective.

DOI： 10.1299/jsmea.47.305

Web of Science

researchmap

DOI： 10.2472/jsms.53.856

researchmap

researchmap

DOI： 10.2472/jsms.53.699

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

DOI： 10.1299/jsmea.47.305

researchmap

researchmap

researchmap

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

In this study, we consider the elastic contact problem of half-space indented by flat and rigid punch with arbitrary cross section. The contact area of the punch is transformed into an unit circle by Schwarz-Christoffel mapping transformation. In the mapping plane, we assume the contact stress by the series terms with singularity. The coefficients of terms in the series are determined by using least square method. In each case of regular flat and polygonal punches such as pentagonal, hexagonal, octagonal ones and so on, we obtain the contact stress distribution approximately so that the displacements are constant in the contact area. In the case of regular flat and square punch with round corners, we obtain similar results. Then, we give the approximate expressions of contact stress for the flat and rigid punch with arbitrary cross section.

DOI： 10.1299/kikaia.69.1545

CiNii Books

researchmap

Other Link： http://hdl.handle.net/10559/13915

researchmap

researchmap

Language：Japanese   Publisher：日本非破壊検査協会  

CiNii Books

CiNii Research

researchmap

researchmap

researchmap

researchmap

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

This paper utilizes the potential function method to analyze the problem of circular uniform or linear variation of pressure and electric displacement on the surface of piezoelectric half space. The half space is taken as transversely isotropic piezoelectric, where the planes of isotropy are parallel to the free surface. Considering the variation of the boundary conditions, the solutions presented here actually comprise six different boundary value problems. The Green's functions for a point normal force and charge are first used to obtain the potential functions in the form of double integrals. Using the Hankel transform, these integrals are evaluated by converting them into single infinite integrals containing product of the Bessel functions. It is shown that the integrals appearing in the potential functions have been previously evaluated in terms of complete elliptic integrals. Hence the potential functions and the electroelastic fields are presently written in terms of these integrals. Numerical results are presented to illustrate both qualitative and quantitative behavior of the induced electroelastic fields.

DOI： 10.1299/jsmea.44.462

Web of Science

researchmap

researchmap

researchmap

researchmap

Language：English  

When dealing with the mechanics of deformable bodies, the variation of the applied force is one of the most important factors to be considered. The mechanical force acting on a body cannot be measured directly. If a body is loaded quasi-statically and if the body deforms linear-elastically, the deformation at any point of the body is proportional to the applied force. Therefore, the variation of the force can be measured indirectly by measuring the variation of the deformation. However, this principle cannot be applied when a body is subjected to an impulsive force. In this case, the propagation of stress waves inside the body cannot be neglected so that the variation of the deformation at any point of the body is no longer the same as the variation of the applied force. Therefore, impact force is much more difficult to measure than quasi-static force. In order to overcome this difficulty, inverse analysis methods to estimate variations of impact force from measured responses of a body have been studied extensively during the last two decades. This article presents a review of methods of inverse analysis for the indirect measurement of impact force. © 2001 American Society of Mechanical Engineers.

DOI： 10.1115/1.1420194

Scopus

researchmap

researchmap

researchmap

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

This paper considers determination of individual stress components from the sum of the principal stresses obtained experimentally by the thermoelastic stress analysis. The stress separation problem is divided into two parts: (I) an inverse problem to estimate the unknown boundary values from the knowledge of the sum of the principal stresses inside the analysis region, and (2) a forward problem to compute the stress components inside the analysis region based on the estimated boundary values. These two problems can be formulated and solved by the BEM. As the inverse problem is often ill-posed, two techniques are adopted so as to attain an accurate result. One is pre-processing of experimental data, that is filtering based on the compatibility equation. The other is regularization of the inverse problem by Tikhonov's method with Hansen's L-curve method. The effectiveness of developed method is verified by applying it to an experimental data. The effect of configuration of the analysis region on the accuracy of stress separation is also discussed.

DOI： 10.1299/jsmea.43.305

Web of Science

researchmap

DOI： 10.1299/kikaia.66.1075

researchmap

researchmap

Language：English   Publisher：AMERICAN SOCIETY TESTING AND MATERIALS  

The Charpy impact test is one of the most popular techniques for assessing mechanical properties of materials under impact loading. Although many studies have evaluated the impact fracture toughness of materials by using the instrumented Charpy testing machine, there still remains difficulty in obtaining the impact force accurately. In this paper, a technique is developed to remove the effect of mechanical vibration of the instrumented hammer on the output of the sensor. Details for practical application of this technique are also presented. An application of this technique to measure the impact fracture toughness of PMMA is demonstrated. Factors which affect the evaluation. of the impact fracture toughness are discussed.

Web of Science

researchmap

researchmap

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

Thermoelastic stress analysis (TSA) is a technique for measuring stresses through temperature changes induced by the thermoelastic effect of elastic bodies. Unfortunately, TSA can only provide the sum of the principal stresses. In this paper, the stress separation problem to determine individual stress components from the sum of the principal stresses is considered. The problem is divided into two parts: (1) an inverse problem to estimate unknown boundary values from the sum of the principal stresses inside the body, and (2) a direct problem to determine the stress components inside the body based on the estimated boundary values. This two-step approach is formulated and solved by BEM. It is found that the combination of Tikhonov regularization with supplementary data and Hansen's L-curve method is effective for attaining an accurate result of stress separation.

DOI： 10.1299/jsmea.42.618

Web of Science

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

A new numerical technique for evaluating the stress intensity factor (SIF) of arbitary 3-D crack is proposed in this paper. This method is based on the solution of an elliptical crack in infinite elastic body under Mode I loading. In an elliptical crack, partial SIFs, K_Iσ and K_Iω, are derived by fitting the near tip stress and displacement, respectively, distribution in a certain direction to the definition of SIF in plane strain state. A complete SIF, K_I, is calculated with K_Iσ and/or K_Iω in some arbitrary directions. Because the local front of an arbitary 3-D crack can be approximated by a part of an ellipse, K_I for an arbitrary crack can be calculated approximately by the same technique. These K_I's calculated in some directions include the residual, and need to be evaluated by the value of these residuals. Selected the direction that this value is minimum, a calculated K_I can be optimized. This paper shows some example calculated by this method.

DOI： 10.1299/kikaia.65.72

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00058412107?from=CiNii

Language：Japanese   Publisher：Japan Society of Mechanical Engineers  

This paper considers determination of individual stress components from the sum of the principal stresses obtained experimentally by the thermoelastic stress analysis. The stress separation problem is devided into two parts: (1) an inverse problem to estimate the unknown boundary values from the knowledge of the sum of the principal stresses inside the analysis region, and (2) a forward problem to compute the stress components inside the analysis region based on the estimated boundary values. These two problems can be formulated and solved by the BEM. As the inverse problem is often ill-posed, two techniques are adopted so as to attain an accurate result. One is preprocessing of experimental data, that is filtering based on the compatibility equation. The other is regularization of the inverse problem by Tikhonov's method with Hansen's L-curve method. The effectiveness of developed method is verified by applying it to an experimental data. The effect of configuration of the analysis region on the accuracy of stress separation is also discussed.

DOI： 10.1299/kikaia.65.2325

Scopus

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

A new numerical technique for evaluating the stress intensity factor (SIF) of arbitary 3-D crack is proposed in this paper. This method is based on the solution of an elliptical crack in infinite elastic body under Mode I loading. In an elliptical crack, partial SIFs, K_Iσ and K_Iω, are derived by fitting the near tip stress and displacement, respectively, distribution in a certain direction to the definition of SIF in plane strain state. A complete SIF, K_I, is calculated with K_Iσ and/or K_Iω in some arbitrary directions. Because the local front of an arbitary 3-D crack can be approximated by a part of an ellipse, K_I for an arbitrary crack can be calculated approximately by the same technique. These K_I's calculated in some directions include the residual, and need to be evaluated by the value of these residuals. Selected the direction that this value is minimum, a calculated K_I can be optimized. This paper shows some example calculated by this method.

DOI： 10.1299/kikaia.65.72

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00058412107?from=CiNii

DOI： 10.1299/kikaia.65.2325

researchmap

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

In this paper, the axisymmetric torsion problem of compound infinite hollow cylinder with an external annular crack is considered on the basis of the three-dimensional theory of elasticity. The cylinder is composed of two layers of different materials. The problem is reduced to solution of an infinite system of simultaneous equations. The distribution of displacement and shear stress as well as the stress intensity factor K-III are computed for various combinations of the elastic modulus for the inner and outer layers.

DOI： 10.1299/jsmea.41.510

Web of Science

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

This paper is concerned with the inverse problem of impact force, which is to estimate the impact forces acting on bodies from the measurement of their impact responses. As the authors have shown previously both numerical Laplace transformation and its inversion are required to solve the inverse problem. Since the inverse analysis is based on experimental data and, in addition, the Laplace inversion is typical of ill-posed problems, straightforward computation tends to provide an unacceptable estimate of the true impact force. Therefore, regularization of the Laplace inversion is necessary to obtain a good estimate of the impact force. In this paper Tikhonov regularization is applied to the numerical Laplace inversion using FFT. Both numerical simulation and experimental results verify that the Tikhonov regularization is effective for improving the accuracy of the estimated impact force. In addition, it is shown that Hansen's L-curve method can be employed to determine appropriately the regularization parameter.

DOI： 10.1299/jsmea.41.473

Web of Science

researchmap

researchmap

DOI： 10.2472/jsms.47.836

researchmap

researchmap

Language：Japanese   Publisher：Soc Mater Sci, Japan  

Polycarbonate (PC) and acrylonitrile butadiene stylene copolymer (ABS) are known as materials having relatively high impact resistance. Recently, polymer alloy of these two materials has been developed to attain higher impact resistance and has become to be used in various engineering products. However, toughening mechanisms of PC/ABS alloy are not still understood very well. In this study, impact fracture toughness of PC/ABS alloy was evaluated for several weight fractions of PC and ABS. Three-point bend specimens were fractured by a drop weight. The time variation of the dynamic stress intensity factor was evaluated and the critical value of the stress intensity at crack initiation was determined. Fracture surfaces were also observed by SEM. The higher fracture toughness has been obtained for the case that the ABS particles are distributed in PC matrix. ABS particles would play a similar role as the butadiene particles in ABS resin during fracture process, i.e., reduction of the stress triaxiality due to the formation of the voids.

DOI： 10.2472/jsms.47.836

Scopus

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS  

Thermoelastic stress analysis (TSA) is a technique for measuring stresses through temperature changes induced by the thermoelastic effect of elastic bodies. Since the TSA can only provide the sum of the principal stresses, stress separation is required to obtain individual stress components. This paper deals with stress separation of TSA data. The problem is divided into two: (1) an inverse problem to estimate the unknown boundary values from the sum of the principal stresses inside the body, and (2) a direct problem to derive the stress components inside the body on the basis of the estimated boundary values. This two-step method can be applied to a wide range of practical problems if both the inverse and direct problems are solved by FEM or BEM. In this study, the problem is formulated by BEM. It is shown that careful treatment of the inverse problem is essential for attaining an accurate result of the stress separation. The combination of the truncated singular value decomposition and Hansen's L-curve method is found to be effective for the purpose.

Web of Science

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with the inverse problem of impact force, which is to estimate impact force acting on bodies from measurement of their impact responses. As the authors have shown previously, both numerical Laplace transformation and its inversion are required to solve the inverse problem. Since the inverse analysis is based on experimental data and, in addition, the Laplace inversion is typical of ill-posed problems, straightforward computation tends to provide unacceptable estimate of impact force. Therefore, regularization of the Laplace inversion is necessary to obtain a good estimate of the impact force. In this paper, Tikhonov regularization in applied to the numerical Laplace inversion by using FFT. Both numerical simulation and experimental verification show that the Tikhonov regularization is effective for improving estimation accuracy of the impact force. In addition, to appropriately determine the regularization parameter, Hansen's L-curve method is found to be effective.

DOI： 10.1299/kikaia.63.2503

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00050789009?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

In this paper, the axisymmetric torsion problem of compound infinite hollow cylinder with an external annular crack is considered on the basis of the three-dimensional theory of elasticity. The cylinder is composed of two layers of different materials. The problem is reduced to solution of an infinite system of simultaneous equations. Distributions of displacement and shear stress and, in addition, the stress intensity factor KIII are computed for various ratios of inner to outer material shear modulus and for various ratios of inner to outer radius of the cylinder.

DOI： 10.1299/kikaia.63.2351

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00050234639?from=CiNii

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with the inverse problem of impact force, which is to estimate impact force acting on bodies from measurement of their impact responses. As the authors have shown previously, both numerical Laplace transformation and its inversion are required to solve the inverse problem. Since the inverse analysis is based on experimental data and, in addition, the Laplace inversion is typical of ill-posed problems, straightforward computation tends to provide unacceptable estimate of impact force. Therefore, regularization of the Laplace inversion is necessary to obtain a good estimate of the impact force. In this paper, Tikhonov regularization in applied to the numerical Laplace inversion by using FFT. Both numerical simulation and experimental verification show that the Tikhonov regularization is effective for improving estimation accuracy of the impact force. In addition, to appropriately determine the regularization parameter, Hansen's L-curve method is found to be effective.

DOI： 10.1299/kikaia.63.2503

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00050789009?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

In this paper, the axisymmetric torsion problem of compound infinite hollow cylinder with an external annular crack is considered on the basis of the three-dimensional theory of elasticity. The cylinder is composed of two layers of different materials. The problem is reduced to solution of an infinite system of simultaneous equations. Distributions of displacement and shear stress and, in addition, the stress intensity factor KIII are computed for various ratios of inner to outer material shear modulus and for various ratios of inner to outer radius of the cylinder.

DOI： 10.1299/kikaia.63.2351

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00050234639?from=CiNii

researchmap

DOI： 10.1299/kikaia.63.2478

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

DOI： 10.1299/kikaia.63.2478

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00050788972?from=CiNii

Language：English   Publisher：SOC EXPERIMENTAL MECHANICS  

The wavelet transform (WT) is applied to the time-frequency analysis of flexural waves in beams. The WT with the Gabor wavelet decomposes a dispersive wave into each frequency component in the time domain, which enables one to determine the traveling time of a wave along the beam at each frequency, By utilizing this fact, a method is developed to identify the dispersion relation and impact site of beams.

DOI： 10.1007/BF02318009

Web of Science

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper deals with stress separation in thermoelastic stress analysis. The problem of stress separation can be divided into two : (1) an inverse problem to estimate the unknown boundary values from the sum of the principal stresses inside the body, and (2) a direct problem to compute the stress components inside the body based on the estimated boundary values. This two-step method can be applied to a wide range of practical problems if both the inverse and direct problems are solved by FEM or BEM. In this study, the problem is formulated by BEM. It is shown that careful treatment of the inverse problem is essential for attaining an accurate result of the stress separation. The combination of the truncated singular value decomposition and Hansen's L-curve method is found to be effective for that purpose.

DOI： 10.1299/kikaia.62.1204

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00040220079?from=CiNii

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper deals with stress separation in thermoelastic stress analysis. The problem of stress separation can be divided into two : (1) an inverse problem to estimate the unknown boundary values from the sum of the principal stresses inside the body, and (2) a direct problem to compute the stress components inside the body based on the estimated boundary values. This two-step method can be applied to a wide range of practical problems if both the inverse and direct problems are solved by FEM or BEM. In this study, the problem is formulated by BEM. It is shown that careful treatment of the inverse problem is essential for attaining an accurate result of the stress separation. The combination of the truncated singular value decomposition and Hansen's L-curve method is found to be effective for that purpose.

DOI： 10.1299/kikaia.62.1204

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00040220079?from=CiNii

researchmap

Language：English   Publisher：ASME-AMER SOC MECHANICAL ENG  

A new approach is presented for investigating the dispersive character of structural waves. The wavelet transform is applied to the time-frequency analysis of dispersive waves. The flexural wave induced in a beam by lateral impact is considered. It is shown that the wavelet transform using the Gabor wavelet effectively decomposes the strain response into its time-frequency components. In addition, the peaks of the time-frequency distribution indicate the arrival times of waves. By utilizing this fact, the dispersion relation of the group velocity cart be accurately identified for a wide range of frequencies.

Web of Science

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS SANSHIN HOKUSEI BLDG  

This paper treats an inverse problem to estimate the magnitude and direction of impact force acting on a body of arbitrary shape. Three directional components of the impact force vector can be estimated from responses measured at more than three points of the body by means of deconvolution. It is pointed out that the impact force cannot always be estimated satisfactorily since the inverse problem is ill-posed or ill-conditioned in some situations. To improve the estimation accuracy, the least squares method based on the singular value decomposition is adopted. The validity of this method is demonstrated through an experiment in which the impact force acting on a simply supported beam is estimated from strain responses measured by strain gages.

Web of Science

researchmap

Language：English  

A boundary element method (BEM) is applied to thermoelastic contact problems where thermal resistance at the contact interface is not negligible. The displacement, traction, temperature and temperature gradient in the contact zone are unknown quantities to be determined numerically. Due to the existence of thermal resistance, temperature and stress fields are mutually coupled. To solve the problem, two kinds of methods are presented. In the first method, the solution is obtained by minimizing a suitably defined objective function. In the second method, discretized equations of each of the bodies in contact are computed alternately until all prescribed boundary conditions are satisfied. The applicability of these methods to practical problems is examined through several numerical examples. © 1995.

DOI： 10.1016/0955-7997(95)00039-Q

Scopus

researchmap

researchmap

DOI： 10.1299/kikaia.61.153

researchmap

Language：English   Publisher：ELSEVIER SCI LTD  

A boundary element method (BEM) is applied to thermoelastic contact problems where thermal resistance at the contact interface is not negligible. The displacement, traction, temperature and temperature gradient in the contact zone are unknown quantities to be determined numerically. Due to the existence of thermal resistance, temperature and stress fields are mutually coupled. To solve the problem, two kinds of methods are presented. In the first method, the solution is obtained by minimizing a suitably defined objective function. In the second method, discretized equations of each of the bodies in contact are computed alternately until all prescribed boundary conditions are satisfied. The applicability of these methods to practical problems is examined through several numerical. examples.

DOI： 10.1016/0955-7997(95)00039-Q

Web of Science

researchmap

researchmap

DOI： 10.1299/kikaia.61.153

researchmap

DOI： 10.1299/kikaia.60.1572

researchmap

DOI： 10.1299/kikaia.60.1572

researchmap

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper treats an inverse problem for estimating the magnitude and direction of an impact force acting on a body of arbitrary shape. It is shown that three directional components of the impact force vector can be estimated from responses measured at more than three points of the body by means of deconvolution. It is pointed out that the impact force cannot always be estimated satisfactorily since the inverse problem is ill-posed and/or ill-conditioned in some situations. For improving the estimation accuracy, the singular value decomposition technique is adopted. The validity of the present method is demonstrated through an experiment in which an impact force acting on a simply supported beam is estimated from strain responses measured by strain gages.

DOI： 10.1299/kikaia.59.572

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00019980584?from=CiNii

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper treats an inverse problem for estimating the magnitude and direction of an impact force acting on a body of arbitrary shape. It is shown that three directional components of the impact force vector can be estimated from responses measured at more than three points of the body by means of deconvolution. It is pointed out that the impact force cannot always be estimated satisfactorily since the inverse problem is ill-posed and/or ill-conditioned in some situations. For improving the estimation accuracy, the singular value decomposition technique is adopted. The validity of the present method is demonstrated through an experiment in which an impact force acting on a simply supported beam is estimated from strain responses measured by strain gages.

DOI： 10.1299/kikaia.59.572

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00019980584?from=CiNii

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS SANSHIN HOKUSEI BLDG  

The present study is concerned with a method for estimating the impact load acting on a body of arbitrary shape. The authors have already shown that the impact load can be estimated from the impact response of the body by an inverse analysis. In practical application, the impact response data involve noise caused by the measurement system. Since the inverse analysis is sometimes ill-conditioned, such noise tends to be expanded and the estimate of the impact load is obscured by noise. In order to overcome this difficulty, we present a method to minimize the mean square error of the estimate by applying the Wiener filtering theory. We demonstrate the applicability of the present method by numerical simulation of the longitudinal impact of a rod.

Web of Science

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS SANSHIN HOKUSEI BLDG  

The Laplace transform is known as one of the most useful mathematical tools for solving a wide range of engineering problems. For its application to theoretical or numerical analyses, methods of numerical inversion have been studied extensively. On the other hand, the method of numerical transformation has not yet been studied very much. This is one of the reasons why few applications of the Laplace transform to experimental analysis have been reported. In the present paper, a method for numerical Laplace transformation and inversion utilizing the fast Fourier transform (FFT) algorithm is studied with the intention of applying it to experimental analysis. A discrete Laplace transform pair is formulated as in the discrete Fourier transform pair. The numerical accuracy of the present method is evaluated for the sinusoidal function and step function. A chart is presented for determining parameters for computation so as to attain a specified accuracy.

Web of Science

researchmap

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS SANSHIN HOKUSEI BLDG  

This paper is concerned with a method for measuring an impact load acting on a body of arbirary shape. The present method is estimation of the impact load from strain response of the body by deconvolution. The transfer function between the impact load and the strain response is estimated by dynamic calibration. It is often difficult to obtain a good estimate of the impact load since the deconvolution is mathematically ill-posed and expands noises involved in measured signals. In this paper, we compare five methods to estimate the transfer function so as to obtain a good estimate of the impact load by deconvolution. Moreover, we apply the present method to the instrumentation of a Charpy impact testing machine and demonstrate its effectiveness.

Web of Science

researchmap

Language：English   Publisher：UNIV TOKYO PRESS  

Web of Science

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

The present study is concerned with a method for estimating impact load acting on a body of arbitrary shape. It is known that the impact load can be estimated from the impact response of the body by an inverse analysis. In practical situations, the impact response data involves noise caused by the measurement system. Since the inverse analysis is usually ill-conditioned, such noise tends to be expanded and the estimated impact load is obscured by noise. For solving this problem, we show a method to minimize the mean square error of estimation by applying the Wiener filtering theory. We demonstrate the availability of the present method by numerical simulation on the longitudinal impact of the rod.

DOI： 10.1299/kikaia.57.2727

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00095291710?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

The Laplace transformation is known as one of the most powerful mathematical techniques for solving wide range of problems in engineering. For its application to practical problems, many authors have extensively studied methods of numerical inversion. On the other hand, the method of numerical transformation has not been studied very much. For this reason, most of the applications were limited to theoretical or numerical analysis and there were few applications to experimental analysis. To overcome this problem, both of the numerical transformation and inversion are studied in this paper. Numerical accuracy is evaluated and discussed using two test functions, sinusoidal and step function. A chart is presented for determining the parameters of computation under a specified accuracy.

DOI： 10.1299/kikaia.57.2523

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00011967057?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with a contact problem between an elastic half-space and a rigid elliptical punch subjected to translation parallel to the surface of the half-space. In such a problem, the normal contact stress within the contact region is much smaller than the tangential stress and is usually assumed to be zero for simplicity of the analysis. In this study, we treat the problem as a mixed boundary value problem in which the surface displacements are specified inside the contact region and the surface stresses are zero outside. Therefore, the normal contact stress is not zero within the contact region. The problem is formulated in the form of simultaneous integral equations with kernels involving Bessel functions. It is reduced to the inhomogeneous Hilbert problem with infinite unknown functions by using Abel transformation and Plemelj formulae. A general solution for the contact stress and the surface displacement is given. The distributions of stress and displacement are shown for the case of a flat-bottom punch and compared with those of the result when the normal contact stress is assumed to be zero.

DOI： 10.1299/kikaia.57.879

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00008886156?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

The Laplace transformation is known as one of the most powerful mathematical techniques for solving wide range of problems in engineering. For its application to practical problems, many authors have extensively studied methods of numerical inversion. On the other hand, the method of numerical transformation has not been studied very much. For this reason, most of the applications were limited to theoretical or numerical analysis and there were few applications to experimental analysis. To overcome this problem, both of the numerical transformation and inversion are studied in this paper. Numerical accuracy is evaluated and discussed using two test functions, sinusoidal and step function. A chart is presented for determining the parameters of computation under a specified accuracy.

DOI： 10.1299/kikaia.57.2523

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00011967057?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with a contact problem between an elastic half-space and a rigid elliptical punch subjected to translation parallel to the surface of the half-space. In such a problem, the normal contact stress within the contact region is much smaller than the tangential stress and is usually assumed to be zero for simplicity of the analysis. In this study, we treat the problem as a mixed boundary value problem in which the surface displacements are specified inside the contact region and the surface stresses are zero outside. Therefore, the normal contact stress is not zero within the contact region. The problem is formulated in the form of simultaneous integral equations with kernels involving Bessel functions. It is reduced to the inhomogeneous Hilbert problem with infinite unknown functions by using Abel transformation and Plemelj formulae. A general solution for the contact stress and the surface displacement is given. The distributions of stress and displacement are shown for the case of a flat-bottom punch and compared with those of the result when the normal contact stress is assumed to be zero.

DOI： 10.1299/kikaia.57.879

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00008886156?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with a method for measuring an impact load acting on a body of arbitrary shape. The impact load is determined from the strain response of the body by the deconvolution procedure which is performed in the frequency domain by using Laplace transformation. The transfer function is estimated from the result of the calibration experiment. The deconvolution is one of the ill-posed problems, and it is usually difficult to obtain a good result. In particular, high- frequency noise involved in the measured signal is often expanded to obscure the result. For this problem, we used five estimators of the transfer function and investigated which of them gives the most suitable transfer function for the deconvolution of experimental data. The efficiency of the method is demonstrated by applying it to the instrumentation of the Charpy impact testing machine.

DOI： 10.1299/kikaia.57.424

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00008840479?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with a method for measuring an impact load acting on a body of arbitrary shape. The impact load is determined from the strain response of the body by the deconvolution procedure which is performed in the frequency domain by using Laplace transformation. The transfer function is estimated from the result of the calibration experiment. The deconvolution is one of the ill-posed problems, and it is usually difficult to obtain a good result. In particular, high- frequency noise involved in the measured signal is often expanded to obscure the result. For this problem, we used five estimators of the transfer function and investigated which of them gives the most suitable transfer function for the deconvolution of experimental data. The efficiency of the method is demonstrated by applying it to the instrumentation of the Charpy impact testing machine.

DOI： 10.1299/kikaia.57.424

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00008840479?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

The present study is concerned with a method for estimating impact load acting on a body of arbitrary shape. It is known that the impact load can be estimated from the impact response of the body by an inverse analysis. In practical situations, the impact response data involves noise caused by the measurement system. Since the inverse analysis is usually ill-conditioned, such noise tends to be expanded and the estimated impact load is obscured by noise. For solving this problem, we show a method to minimize the mean square error of estimation by applying the Wiener filtering theory. We demonstrate the availability of the present method by numerical simulation on the longitudinal impact of the rod.

DOI： 10.1299/kikaia.57.2727

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00095291710?from=CiNii

Language：English   Publisher：JAPAN SOC MECHANICAL ENGINEERS SANSHIN HOKUSEI BLDG  

Web of Science

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

For the contact problems in the theory of two-dimemsional elasticity, in which the rigid punch is pressed on the elastic half plane, we usually use the contact condition between the vertical displacement and the punch profile, and ignore the effect of the tangential displacement. However, the surface deformation on the contact area is different from the punch profile because the deformation is given by the vector of both displacements. In the present paper, we analyze the same problem under the more rigorous contact condition in consideration of both displacements, as follows: (v)_y=0+kf'(x)·(u)_y=0=δ₀-kf(x), |x|≤a where (v)_y=0 and (u)_y=0 are the vertical and the tangential displacements on the contact area, respectively, δ₀ the indentation displacement and kf(x) the punch profile. We calculate numerically the two cases of the parabolic and the wedge punches, and discuss the effect of the tangential displacement on the stress state. In the results, we show that all of the contact stresses, the indentation forses and the indentation displacements are smaller than those in the conventional cases.

DOI： 10.1299/kikaia.56.1254

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00002871905?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with a contact problem for an elastic layer on a rigid substrate indented by multiple rigid concentric-annular stamps. This problem is a mixed boundary value problem in which the surface displacement of the layer is specified inside the concentric-annular regions and the traction is zero outside. It is assumed that contact is free from friction so that the shear traction on the whole surface of the layer is zero. The problem is reduced to infinite simultaneous algebraic equations by using Fourier series expansion of the normal traction within the contact region. General solutions for the contact stress and the surface displacement are presented. Sone numerical results are given in graphical form, and the interaction of the contact stresses caused by each annulus is investigated.

DOI： 10.1299/kikaia.56.943

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00002666587?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with a contact problem for an elastic layer on a rigid substrate indented by multiple rigid concentric-annular stamps. This problem is a mixed boundary value problem in which the surface displacement of the layer is specified inside the concentric-annular regions and the traction is zero outside. It is assumed that contact is free from friction so that the shear traction on the whole surface of the layer is zero. The problem is reduced to infinite simultaneous algebraic equations by using Fourier series expansion of the normal traction within the contact region. General solutions for the contact stress and the surface displacement are presented. Sone numerical results are given in graphical form, and the interaction of the contact stresses caused by each annulus is investigated.

DOI： 10.1299/kikaia.56.943

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00002666587?from=CiNii

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

For the contact problems in the theory of two-dimemsional elasticity, in which the rigid punch is pressed on the elastic half plane, we usually use the contact condition between the vertical displacement and the punch profile, and ignore the effect of the tangential displacement. However, the surface deformation on the contact area is different from the punch profile because the deformation is given by the vector of both displacements. In the present paper, we analyze the same problem under the more rigorous contact condition in consideration of both displacements, as follows: (v)_y=0+kf'(x)·(u)_y=0=δ₀-kf(x), |x|≤a where (v)_y=0 and (u)_y=0 are the vertical and the tangential displacements on the contact area, respectively, δ₀ the indentation displacement and kf(x) the punch profile. We calculate numerically the two cases of the parabolic and the wedge punches, and discuss the effect of the tangential displacement on the stress state. In the results, we show that all of the contact stresses, the indentation forses and the indentation displacements are smaller than those in the conventional cases.

DOI： 10.1299/kikaia.56.1254

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00002871905?from=CiNii

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with the contact problem between an elastic half-space and a rigid elliptical punch subjected to a torsional moment. It is assumed that the contact is completely adhesive and that the normal pressure within the contact region cannot be neglected. This problem is a mixed boundary value problem in which the displacements are specified inside the elliptical region and the surface stresses are specified and zero outside. The problem is reduced to solving simultaneous integral equations with kernels involving Bessel functions of the first kind of integer orders. It is further reduced to solving the Hilbert problem with infinite unknown functions by using the Abel transform and the Plemelj formulae. A general method for solving the problem is given. Numerical results for contact stresses and surface displacements are shown in graphical form for various aspect ratios of the ellipse.

DOI： 10.1299/kikaia.55.273

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00224040592?from=CiNii

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

This paper is concerned with the contact problem between an elastic half-space and a rigid elliptical punch subjected to a torsional moment. It is assumed that the contact is completely adhesive and that the normal pressure within the contact region cannot be neglected. This problem is a mixed boundary value problem in which the displacements are specified inside the elliptical region and the surface stresses are specified and zero outside. The problem is reduced to solving simultaneous integral equations with kernels involving Bessel functions of the first kind of integer orders. It is further reduced to solving the Hilbert problem with infinite unknown functions by using the Abel transform and the Plemelj formulae. A general method for solving the problem is given. Numerical results for contact stresses and surface displacements are shown in graphical form for various aspect ratios of the ellipse.

DOI： 10.1299/kikaia.55.273

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00224040592?from=CiNii

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

In this paper, an attempt is made to analyze the impulsive stresses in a glass plate subjected to the transverse impact of steel balls. For the case of a mass striking an infinite glass plate, the contact force variation is obtained by solving a nonlinear integral equation given by the use of Lagrange's classical plate theory and Hertz's law of contact. By regarding this force as an impact load for the case of the central impact of a steel ball on a supported circular glass plate, the impulsive stresses in a glass plate are analyzed using the three-dimensional dynamic theory of elasticity. Finally, it is shown that these analytical results are in good agreement with the experimental results.

DOI： 10.1299/kikaia.52.525

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00208982191?from=CiNii

Language：Japanese   Publisher：The Japan Society of Mechanical Engineers  

In this paper, an attempt is made to analyze the impulsive stresses in a glass plate subjected to the transverse impact of steel balls. For the case of a mass striking an infinite glass plate, the contact force variation is obtained by solving a nonlinear integral equation given by the use of Lagrange's classical plate theory and Hertz's law of contact. By regarding this force as an impact load for the case of the central impact of a steel ball on a supported circular glass plate, the impulsive stresses in a glass plate are analyzed using the three-dimensional dynamic theory of elasticity. Finally, it is shown that these analytical results are in good agreement with the experimental results.

DOI： 10.1299/kikaia.52.525

CiNii Books

researchmap

Other Link： https://jlc.jst.go.jp/DN/JALC/00208982191?from=CiNii

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

researchmap

Presentation type：Poster presentation  

researchmap

Presentation type：Poster presentation  

researchmap

researchmap