Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_172
N. Sumi
A solution is presented for the stress-wave response of a partially transparent finite elastic circular plate with a penny-shaped crack subjected to impulsive electromagnetic radiation. The radiation is assumed to occur at a constant rate for the duration of the pulse, to be deposited with a radial Gaussian distribution and to diminish exponentially with distance from the exposed surface of the plate. The development of the analysis is based on the equations of uncoupled dynamic thermoelasticity with heat conduction neglected. The numerical procedure employs explicit finite difference approximations with second-order accuracy based on the integration of the governing equations along the bicharacteristics. Numerical calculations are carried out for the dynamic behavior of the thermal stresses and the stress intensity factors, and the results are shown in figures.
{"title":"Dynamic Thermal Stresses in a Finite Circular Plate with a Penny-Shaped Crack Generated by Impulsive Heating","authors":"N. Sumi","doi":"10.1299/JSMEA1993.39.2_172","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_172","url":null,"abstract":"A solution is presented for the stress-wave response of a partially transparent finite elastic circular plate with a penny-shaped crack subjected to impulsive electromagnetic radiation. The radiation is assumed to occur at a constant rate for the duration of the pulse, to be deposited with a radial Gaussian distribution and to diminish exponentially with distance from the exposed surface of the plate. The development of the analysis is based on the equations of uncoupled dynamic thermoelasticity with heat conduction neglected. The numerical procedure employs explicit finite difference approximations with second-order accuracy based on the integration of the governing equations along the bicharacteristics. Numerical calculations are carried out for the dynamic behavior of the thermal stresses and the stress intensity factors, and the results are shown in figures.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"63 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134127915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_231
Teruo Nakamura, Kenji Saito, S. Araki
In our previous paper, an approximate solution to the main crack-microdefect interaction model was derived using a main crack stress field, and the effect of a microdefect ahead of a main crack on the strength of solids was discussed in terms of the model. In the present paper, in order to investigate more precisely the above effect, the main crack-microdefect interaction model is formulated more specifically based on the method of continuously distributed theory of dislocations, and the distribution functions for both a main crack and a microdefect are obtained. As a result, we obtain stress intensity factors K both at the tip of a main crack and a microdefect in the closed form. Using these K values, we elucidate the effective range of the above model and the crack shielding effect by a microdefect. Furthermore, the crack length dependence of the fracture strength and fracture toughness of engineering ceramics can be explained well theoretically using the present model.
{"title":"Effect of a Microdefect ahead of a Main Crack on Strength of Solids : Exact Solution to the Main Crack-Microdefect Interaction Model","authors":"Teruo Nakamura, Kenji Saito, S. Araki","doi":"10.1299/JSMEA1993.39.2_231","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_231","url":null,"abstract":"In our previous paper, an approximate solution to the main crack-microdefect interaction model was derived using a main crack stress field, and the effect of a microdefect ahead of a main crack on the strength of solids was discussed in terms of the model. In the present paper, in order to investigate more precisely the above effect, the main crack-microdefect interaction model is formulated more specifically based on the method of continuously distributed theory of dislocations, and the distribution functions for both a main crack and a microdefect are obtained. As a result, we obtain stress intensity factors K both at the tip of a main crack and a microdefect in the closed form. Using these K values, we elucidate the effective range of the above model and the crack shielding effect by a microdefect. Furthermore, the crack length dependence of the fracture strength and fracture toughness of engineering ceramics can be explained well theoretically using the present model.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114991534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_223
P. Dechaumphai
An adaptive finite element technique for thermal stress analysis of built-up structures has been developed. A finite element formulation for a triangular membrane element and a new plate bending element, used for modelling such structures under both mechanical and thermal loadings, is presented. The associated finite element matrices have been derived in closed form. The performance of the new plate bending element is evaluated for a plate with temperature gradient through its thickness by comparing the predicted solution with the exact solution. The effectiveness of the adaptive meshing technique combined with the finite element method is evaluated by thermal stress analysis of a built-up structure with intersecting panels. The application demonstrates that the adaptive meshing technique can provide an accurate solution with fewer elements and shorter computational time than the standard finite element procedure.
{"title":"Adaptive Finite Element Technique for Thermal Stress Analysis of Built-Up Structures","authors":"P. Dechaumphai","doi":"10.1299/JSMEA1993.39.2_223","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_223","url":null,"abstract":"An adaptive finite element technique for thermal stress analysis of built-up structures has been developed. A finite element formulation for a triangular membrane element and a new plate bending element, used for modelling such structures under both mechanical and thermal loadings, is presented. The associated finite element matrices have been derived in closed form. The performance of the new plate bending element is evaluated for a plate with temperature gradient through its thickness by comparing the predicted solution with the exact solution. The effectiveness of the adaptive meshing technique combined with the finite element method is evaluated by thermal stress analysis of a built-up structure with intersecting panels. The application demonstrates that the adaptive meshing technique can provide an accurate solution with fewer elements and shorter computational time than the standard finite element procedure.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122881438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_259
M. Chu, Shigemi Sato, Y. Kobayashi, K. Ando
Both mullite/SiC (0.27 μm and 1.20 μm) and mullite/TiC composite ceramics were prepared by hotpressing at 1650°C under 35 MPa for 4h. Room-temperature bending fracture stress, Young's modulus, Vicker's hardness and fracture toughness were investigated as functions of SiC and TiC volume fraction (0-20%). Grain growth of mullite was prevented by the existence of dispersed particles (SiC, TiC) in the matrix. As a result, bending fracture stress of both mullite/SiC and mullite/TiC composite ceramics was improved. In the case of the mullite/SiC system, bending fracture stress inceased with increasing SiC content and showed a maximum value of 604 MPa at 20 vol%, which was about 80% higher than that of monolithic mullite. On the other hand, fracture toughness of mullite/TiC ceramic composite was observed to incease from 2.65 to 3.9 MPa√m with the addition of 20 vol% TiC. Correspondingly, the bending-fracture stress increased from 330 to 410 MPa. The strengthening mechanism of thermal treatment in air was also investigated for mullite/SiC composite ceramics and it was concluded to be useful for increasing bending fracture stress. Detailed reseach on the microstructure showed that the Hall-Petch relationship was satisfied for grain size and bending fracture stress.
{"title":"Strengthening of Mullite by Dispersion of Carbide Ceramics Particles","authors":"M. Chu, Shigemi Sato, Y. Kobayashi, K. Ando","doi":"10.1299/JSMEA1993.39.2_259","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_259","url":null,"abstract":"Both mullite/SiC (0.27 μm and 1.20 μm) and mullite/TiC composite ceramics were prepared by hotpressing at 1650°C under 35 MPa for 4h. Room-temperature bending fracture stress, Young's modulus, Vicker's hardness and fracture toughness were investigated as functions of SiC and TiC volume fraction (0-20%). Grain growth of mullite was prevented by the existence of dispersed particles (SiC, TiC) in the matrix. As a result, bending fracture stress of both mullite/SiC and mullite/TiC composite ceramics was improved. In the case of the mullite/SiC system, bending fracture stress inceased with increasing SiC content and showed a maximum value of 604 MPa at 20 vol%, which was about 80% higher than that of monolithic mullite. On the other hand, fracture toughness of mullite/TiC ceramic composite was observed to incease from 2.65 to 3.9 MPa√m with the addition of 20 vol% TiC. Correspondingly, the bending-fracture stress increased from 330 to 410 MPa. The strengthening mechanism of thermal treatment in air was also investigated for mullite/SiC composite ceramics and it was concluded to be useful for increasing bending fracture stress. Detailed reseach on the microstructure showed that the Hall-Petch relationship was satisfied for grain size and bending fracture stress.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128827884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_237
T. Abe, Xiaoyu Lu, Masashi Nouno, T. Nanba
The macroscopic plastic deformation of polycrystalline metals, as revealed by features such as yield surface under multiaxial stress or the normality rule, is related to the microscopic slips in grains. In the present paper, a rate-type constitutive equation and a constant stress model of polycrystals are adopted and the equal-strain-rate curves under biaxial stress, which are equivalent to the yield curves in plasticity, are studied. The rate-sensitivity exponent in the rate-type constitutive equation is closely related to the number of active slip systems on the yield curves. Hence, it is possible to examine the effect of the number of active slip systems on the yield curve. The yield curves of fcc single crystals as well as fcc polycrystalline metals are calculated. The shape of the obtained yield curve is dependent on the number of active slip systems as well as the distribution of strain in polycrystals. The direction of strain rate vectors is also discussed. A new model of polycrystals called the constant maximum shear strain rate model is proposed.
{"title":"Numerical Study on Yield Curves of FCC Metals Based on Rate-Dependent Crystal Slips","authors":"T. Abe, Xiaoyu Lu, Masashi Nouno, T. Nanba","doi":"10.1299/JSMEA1993.39.2_237","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_237","url":null,"abstract":"The macroscopic plastic deformation of polycrystalline metals, as revealed by features such as yield surface under multiaxial stress or the normality rule, is related to the microscopic slips in grains. In the present paper, a rate-type constitutive equation and a constant stress model of polycrystals are adopted and the equal-strain-rate curves under biaxial stress, which are equivalent to the yield curves in plasticity, are studied. The rate-sensitivity exponent in the rate-type constitutive equation is closely related to the number of active slip systems on the yield curves. Hence, it is possible to examine the effect of the number of active slip systems on the yield curve. The yield curves of fcc single crystals as well as fcc polycrystalline metals are calculated. The shape of the obtained yield curve is dependent on the number of active slip systems as well as the distribution of strain in polycrystals. The direction of strain rate vectors is also discussed. A new model of polycrystals called the constant maximum shear strain rate model is proposed.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126678369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_192
H. Kumasaka, K. Hirashima
We describe the complementary relationship between stress and displacement for nonlocal elasticity. This relationship is derived from the definition of nonlocal stress and the equilibrium equation. The stress solutions in an infinite plane subjected to a uniform compressed load are given. It is assumed that the nonlocal effects of the matrix and the inclusion are the same, and these effects cross the boundary between the matrix and inclusion. The stress distribution around a hole is drawn graphically using this solution. One of the effects of nonlocal elasticity is the development of a stress relaxation zone around a hole.
{"title":"Stress Distributions around Circular Inclusion in Infinite Plane for Nonlocal Elasticity : Matrix and Circular Inclusion have the Same Nonlocal Coefficients","authors":"H. Kumasaka, K. Hirashima","doi":"10.1299/JSMEA1993.39.2_192","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_192","url":null,"abstract":"We describe the complementary relationship between stress and displacement for nonlocal elasticity. This relationship is derived from the definition of nonlocal stress and the equilibrium equation. The stress solutions in an infinite plane subjected to a uniform compressed load are given. It is assumed that the nonlocal effects of the matrix and the inclusion are the same, and these effects cross the boundary between the matrix and inclusion. The stress distribution around a hole is drawn graphically using this solution. One of the effects of nonlocal elasticity is the development of a stress relaxation zone around a hole.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121138793","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_179
K. Yamazaki, N. Tsubosaka
A finite element formulation using the penalty function method to analyze exactly the junction of plate and shell built-up structures is suggested for an isoparametric shell element. The connectivity condition at the junction is added to the potential energy functional by the penalty parameter and the interpolating function of displacements. This formulation yields an integral-type stiffness matrix of the special junction elements, which can directly evaluate the surface tractions at the junction. The suggested technique is applied to the stress analyses of isotropic and laminated plates with several types of stiffeners, and the validity of the technique is discussed.
{"title":"Stress analysis of junction of plate and shell built-up structures via special finite shell element","authors":"K. Yamazaki, N. Tsubosaka","doi":"10.1299/JSMEA1993.39.2_179","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_179","url":null,"abstract":"A finite element formulation using the penalty function method to analyze exactly the junction of plate and shell built-up structures is suggested for an isoparametric shell element. The connectivity condition at the junction is added to the potential energy functional by the penalty parameter and the interpolating function of displacements. This formulation yields an integral-type stiffness matrix of the special junction elements, which can directly evaluate the surface tractions at the junction. The suggested technique is applied to the stress analyses of isotropic and laminated plates with several types of stiffeners, and the validity of the technique is discussed.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115154911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_246
H. Hagi
In order to study the effects of dissolved hydrogen atoms and hydrogen damage on elongation of mild steel in relation to the susceptibility of iron and steel to hydrogen embrittlement, tensile tests were carried out immediately after cathodic hydrogen charging and after degassing of hydrogen at room temperature. Because cathodic hydrogen charging caused internal damage, such as microcracks (blisters) and plastic deformation owing to hydrogen precipitation, the influence of the dissolved hydrogen on the elongation was distinguished from that of hydrogen damage. The dissolved hydrogen and hydrogen damage were found to cause reversible and irreversible reductions in elongation, respectively.
{"title":"Hydrogen Embrittlement of Mild Steel Charged Cathodically with Hydrogen : Effect of Dissolved Hydrogen and Hydrogen Damage on Elongation of Mild Steel","authors":"H. Hagi","doi":"10.1299/JSMEA1993.39.2_246","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_246","url":null,"abstract":"In order to study the effects of dissolved hydrogen atoms and hydrogen damage on elongation of mild steel in relation to the susceptibility of iron and steel to hydrogen embrittlement, tensile tests were carried out immediately after cathodic hydrogen charging and after degassing of hydrogen at room temperature. Because cathodic hydrogen charging caused internal damage, such as microcracks (blisters) and plastic deformation owing to hydrogen precipitation, the influence of the dissolved hydrogen on the elongation was distinguished from that of hydrogen damage. The dissolved hydrogen and hydrogen damage were found to cause reversible and irreversible reductions in elongation, respectively.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114182475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_157
N. Hasebe, Seiji Kato, Atsusi Ueda, Takuji Nakamura
A bimaterial problem of strips which are bonded at their ends is solved. The bonded part is one part and debondings occur on both sides of the interface. The debonding lengths are changed, and concentrated loads are applied at the tips of each strip. The complex variable method and a rational mapping function are used for the analysis. Stress distributions are shown for two different locations of the interface. Stress intensity of debonding is defined and the values are obtained for various debonding lengths. Debonding and the effect of material constants on debonding are also investigated.
{"title":"Stress Analysis of Bimaterial Strip with Debondings under Tension","authors":"N. Hasebe, Seiji Kato, Atsusi Ueda, Takuji Nakamura","doi":"10.1299/JSMEA1993.39.2_157","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_157","url":null,"abstract":"A bimaterial problem of strips which are bonded at their ends is solved. The bonded part is one part and debondings occur on both sides of the interface. The debonding lengths are changed, and concentrated loads are applied at the tips of each strip. The complex variable method and a rational mapping function are used for the analysis. Stress distributions are shown for two different locations of the interface. Stress intensity of debonding is defined and the values are obtained for various debonding lengths. Debonding and the effect of material constants on debonding are also investigated.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128789382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-04-15DOI: 10.1299/JSMEA1993.39.2_166
H. Miura, N. Ishitsuka, N. Saito, H. Ohta, C. Hashimoto, S. Ikeda
Stress fields in transistor structures are analyzed with consideration of the internal stresses of thin films. Internal stresses of amorphous silicon and tungsten silicide films are measured by detecting changes in the surface curvature of film-covered substrates as a function of temperature. Internal stresses of both films change upon annealing due to phase transitions, and reach about 1000 MPa. The stress predicted for transistor structures without considering the internal stress of the films differs markedly from results obtained using microscopic Raman spectroscopy. On the other hand, the stress predicted with consideration of film internal stress agrees very well with measured data. Stress design is performed for an actual transistor structure by adjusting the annealing temperature depending on the internal stress of an amorphous silicon thin film to eliminate the generation of dislocations. It is confirmed that stress design is effective in eliminating dislocations in transistor structures, thus improving device reliability.
{"title":"Stress Analysis of Transistor Structures Considering the Internal Stress of Thin Films","authors":"H. Miura, N. Ishitsuka, N. Saito, H. Ohta, C. Hashimoto, S. Ikeda","doi":"10.1299/JSMEA1993.39.2_166","DOIUrl":"https://doi.org/10.1299/JSMEA1993.39.2_166","url":null,"abstract":"Stress fields in transistor structures are analyzed with consideration of the internal stresses of thin films. Internal stresses of amorphous silicon and tungsten silicide films are measured by detecting changes in the surface curvature of film-covered substrates as a function of temperature. Internal stresses of both films change upon annealing due to phase transitions, and reach about 1000 MPa. The stress predicted for transistor structures without considering the internal stress of the films differs markedly from results obtained using microscopic Raman spectroscopy. On the other hand, the stress predicted with consideration of film internal stress agrees very well with measured data. Stress design is performed for an actual transistor structure by adjusting the annealing temperature depending on the internal stress of an amorphous silicon thin film to eliminate the generation of dislocations. It is confirmed that stress design is effective in eliminating dislocations in transistor structures, thus improving device reliability.","PeriodicalId":143127,"journal":{"name":"JSME international journal. Series A, mechanics and material engineering","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127880938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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