Pub Date : 2013-10-24DOI: 10.1109/ISAM.2013.6643527
H. Zhang, P. Zhang, L. Qin, G. Dong
This paper, based on the two-component slip model, numerically analyzes the tribology performances of journal bearings with boundary slip/no-slip regions on the condition of high speed water lubrication. It is demonstrated that journal bearings with a whole slip sleeve reduce the friction drag and the load carrying capacity. Bearings with a slip/no-slip interval region on sleeve, however, can shorten the cavitation region and enhance the average film pressure, which means the enhancement of load carrying capacity and the reduction of friction drag. When the boundary of the slip and no-slip regions is close to the location between the pressure peak and 180° of the bearing, the load carrying capacity reaches its maximum. Different to loading capacity, friction drag is reduced dramatically with the increase of the slip region. For bearings with small eccentricity ratio, small width and large diameter, the loading capacity and the friction drag can be enhanced and reduced more significantly.
{"title":"A boundary slip region design on journal bearingsunder high speed water lubrication","authors":"H. Zhang, P. Zhang, L. Qin, G. Dong","doi":"10.1109/ISAM.2013.6643527","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643527","url":null,"abstract":"This paper, based on the two-component slip model, numerically analyzes the tribology performances of journal bearings with boundary slip/no-slip regions on the condition of high speed water lubrication. It is demonstrated that journal bearings with a whole slip sleeve reduce the friction drag and the load carrying capacity. Bearings with a slip/no-slip interval region on sleeve, however, can shorten the cavitation region and enhance the average film pressure, which means the enhancement of load carrying capacity and the reduction of friction drag. When the boundary of the slip and no-slip regions is close to the location between the pressure peak and 180° of the bearing, the load carrying capacity reaches its maximum. Different to loading capacity, friction drag is reduced dramatically with the increase of the slip region. For bearings with small eccentricity ratio, small width and large diameter, the loading capacity and the friction drag can be enhanced and reduced more significantly.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131030677","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643451
Aibin Zhu, Yulei Yang, Hongyu Xiao, Wei Chen
In Traditional process for solving performance parameters of fix-pad journal bearing, various formulas of eccentricity ratio and attitude angle are needed for different bearing types. A performance calculation model for all kinds of fix-pad journal bearing based on unified coordinate system is presented in the paper. With bearing center as the origin, this model establishes a unified coordinate system to acquire coordinates of shaft and pads centers. Eccentricity ratio and attitude angle of shaft are calculated via their coordinates. Geometric description of fix-pad journal bearing is unified in this model. Performance calculation results according to this model matches previous work by other researchers very well, yyl1990 which confirms validity of this model.
{"title":"Performance calculation model for fix-pad journal bearing based on unified coordinate","authors":"Aibin Zhu, Yulei Yang, Hongyu Xiao, Wei Chen","doi":"10.1109/ISAM.2013.6643451","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643451","url":null,"abstract":"In Traditional process for solving performance parameters of fix-pad journal bearing, various formulas of eccentricity ratio and attitude angle are needed for different bearing types. A performance calculation model for all kinds of fix-pad journal bearing based on unified coordinate system is presented in the paper. With bearing center as the origin, this model establishes a unified coordinate system to acquire coordinates of shaft and pads centers. Eccentricity ratio and attitude angle of shaft are calculated via their coordinates. Geometric description of fix-pad journal bearing is unified in this model. Performance calculation results according to this model matches previous work by other researchers very well, yyl1990 which confirms validity of this model.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114648818","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643490
Jiaxin Zhao, B. Ma, He-yan Li
A bench experiment was designed to test the rotational speed and torque of the wet clutch, so as to calculate the equivalent friction coefficient. With this coefficient, the unstable behavior of friction systems with lubrication can be researched by a similar method with dry friction systems. Thermoelastic instability theory is chosen as the research method. With this theory, stability boundaries of the system for different hot spot numbers are calculated.
{"title":"Investigation of thermoelastic instabilities of wet clutches","authors":"Jiaxin Zhao, B. Ma, He-yan Li","doi":"10.1109/ISAM.2013.6643490","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643490","url":null,"abstract":"A bench experiment was designed to test the rotational speed and torque of the wet clutch, so as to calculate the equivalent friction coefficient. With this coefficient, the unstable behavior of friction systems with lubrication can be researched by a similar method with dry friction systems. Thermoelastic instability theory is chosen as the research method. With this theory, stability boundaries of the system for different hot spot numbers are calculated.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114867651","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643468
Xiaochao Sheng, Dongsheng Zhang, X. Mei, T. Tao
This paper presents the horizontal control of a novel magnetic suspension stage (MSS) whose travel range is 0.8 mm×0.8 mm in the X and Y axes. Firstly, the dynamic model of MSS in the horizontal is built. And then, based on the three degree-of-freedom (DOF) dynamic model, a decoupling fuzzy sliding mode controller is designed. Finally, planar positioning experiments show that the presented controller provides a good tracking performance and MSS could achieve planar positioning without quadrant error.
{"title":"Decoupling fuzzy sliding mode control of MIMO magnetic suspension stage in XY planar motion","authors":"Xiaochao Sheng, Dongsheng Zhang, X. Mei, T. Tao","doi":"10.1109/ISAM.2013.6643468","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643468","url":null,"abstract":"This paper presents the horizontal control of a novel magnetic suspension stage (MSS) whose travel range is 0.8 mm×0.8 mm in the X and Y axes. Firstly, the dynamic model of MSS in the horizontal is built. And then, based on the three degree-of-freedom (DOF) dynamic model, a decoupling fuzzy sliding mode controller is designed. Finally, planar positioning experiments show that the presented controller provides a good tracking performance and MSS could achieve planar positioning without quadrant error.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115690466","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643488
Xiwei Zhou, Hua Xu, Xianzhi Xiong, Lin Wang
A load distribution model in consideration of ball off size for deep groove ball bearing is put forward. For single off-sized ball, effects of magnitude of off size and external load are analyzed. For multiple off-sized balls, both effects of number and arrangement of off-sized balls on bearing load distribution are studied. For single off-sized ball, the results indicate that ball contact load fluctuation is linearly dependent on the value of off size, and has a non-linear relationship with external load. In addition, the variation of ball contact load is a function of its circumferential position. For multiple off-sized balls, both relative off size value and relative position of off-sized balls have significant effects on load distribution.
{"title":"Load distribution model of deep groove ball bearing with ball off size","authors":"Xiwei Zhou, Hua Xu, Xianzhi Xiong, Lin Wang","doi":"10.1109/ISAM.2013.6643488","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643488","url":null,"abstract":"A load distribution model in consideration of ball off size for deep groove ball bearing is put forward. For single off-sized ball, effects of magnitude of off size and external load are analyzed. For multiple off-sized balls, both effects of number and arrangement of off-sized balls on bearing load distribution are studied. For single off-sized ball, the results indicate that ball contact load fluctuation is linearly dependent on the value of off size, and has a non-linear relationship with external load. In addition, the variation of ball contact load is a function of its circumferential position. For multiple off-sized balls, both relative off size value and relative position of off-sized balls have significant effects on load distribution.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115730122","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643526
Z. Xiong, K. Jia, Xiaodong Yuan, Kaihong Cui, Bin Zhang, Pan Xu
A finite element analysis model for the large diameter and thin-type KDP plate has been built up based on the experimental measurement data of surface profile and its mounting system with different types and sizes fabrication error. The impact of the fabrication error of KDP plate and its mounting system on the additional surface variation of KDP plate has been studied and simulated. It's shown that the fabrication error of the edges of the KDP and the fabrication error with concave shape of support surface are the main reasons of causing the relatively large additional surface variation. The fabrication error of KDP plate also leads to the non-uniform deformation. The fabrication error with convex, the wavy shape of support surface, and the random fabrication error of the strip surface in the mounting system, lead to relatively small additional surface variation. The degree of additional surface variation due to the random fabrication error of support surface is between the former and the later.
{"title":"The additional surface variation of large diameter and thin-type KDP plate caused by fabrication errors","authors":"Z. Xiong, K. Jia, Xiaodong Yuan, Kaihong Cui, Bin Zhang, Pan Xu","doi":"10.1109/ISAM.2013.6643526","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643526","url":null,"abstract":"A finite element analysis model for the large diameter and thin-type KDP plate has been built up based on the experimental measurement data of surface profile and its mounting system with different types and sizes fabrication error. The impact of the fabrication error of KDP plate and its mounting system on the additional surface variation of KDP plate has been studied and simulated. It's shown that the fabrication error of the edges of the KDP and the fabrication error with concave shape of support surface are the main reasons of causing the relatively large additional surface variation. The fabrication error of KDP plate also leads to the non-uniform deformation. The fabrication error with convex, the wavy shape of support surface, and the random fabrication error of the strip surface in the mounting system, lead to relatively small additional surface variation. The degree of additional surface variation due to the random fabrication error of support surface is between the former and the later.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128691275","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643494
Z. Lu, Y. X. Fan, D. Yang, D. C. Li
To improve the room-temperature and medium-temperature bending strengths of Al2O3 matrix ceramic mould for hollow turbine blade, SiC whisker was added. The samples' microstructure and phase were tested by Scanning Electron Microscope and X-Ray Diffraction, the relationship between the bending strength and phase were mainly analyzed. The result shows that the room-temperature bending strength of pre-sintering samples at 1250°C was respectively 19.6MPa and 54.75MPa when the content of SiC whisker was 4wt% and 8wt%. The medium-temperature bending strength of samples was respectively 1.56MPa to 0.91Mpa and 1.85MPa to 1.02MPa when the content of SiC whisker was 4wt% and 8wt% during 400°C to 600°C, and was the lowest at 500°C. After pre-sintering at 1250°C, the shrinkage of the samples with 4wt% and 8wt% SiC whisker was -0.06% and 0.7% respectively. It is possible to fabricate high-performance Al2O3 matrix ceramic mould for hollow turbine blade.
{"title":"The effect of SiC whisker on the performances of Al2O3 matrixceramics mould for hollow turbine blade","authors":"Z. Lu, Y. X. Fan, D. Yang, D. C. Li","doi":"10.1109/ISAM.2013.6643494","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643494","url":null,"abstract":"To improve the room-temperature and medium-temperature bending strengths of Al2O3 matrix ceramic mould for hollow turbine blade, SiC whisker was added. The samples' microstructure and phase were tested by Scanning Electron Microscope and X-Ray Diffraction, the relationship between the bending strength and phase were mainly analyzed. The result shows that the room-temperature bending strength of pre-sintering samples at 1250°C was respectively 19.6MPa and 54.75MPa when the content of SiC whisker was 4wt% and 8wt%. The medium-temperature bending strength of samples was respectively 1.56MPa to 0.91Mpa and 1.85MPa to 1.02MPa when the content of SiC whisker was 4wt% and 8wt% during 400°C to 600°C, and was the lowest at 500°C. After pre-sintering at 1250°C, the shrinkage of the samples with 4wt% and 8wt% SiC whisker was -0.06% and 0.7% respectively. It is possible to fabricate high-performance Al2O3 matrix ceramic mould for hollow turbine blade.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"25 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132089384","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643483
Wen-Jie He, Bo Chu, Rui Gu, Hai-Tao Zhang, B. Shan, Rong Chen
Atomic layer deposition (ALD) technology is a self-limiting ultrathin film deposition method. In ALD reactions, the reaction temperature plays a key role. And generalized predictive control (GPC) algorithm is adopted to control the temperature of a radiant heating reactor. The mathematical model of the system's temperature uniformity is calculated with heat transfer theory. Since temperature control is affected by GPC parameters including soften factor, weighting coefficient, sample time etc, it is necessary to study the effect of these parameters. By experiments, the values of soften factor, weighting coefficient and sampling time could be optimized and then be applied in the process of ALD reactions. And conclusions can be draw that soften factor has the largest impact on the algorithm while the influences of weighting coefficient and sampling time are almost negligible. Efficient temperature control of the ALD reactor chamber using GPC algorithm with optimal parameters is demonstrated.
{"title":"The application of generalized predictive control in the radiant heating atomic layer deposition reactor","authors":"Wen-Jie He, Bo Chu, Rui Gu, Hai-Tao Zhang, B. Shan, Rong Chen","doi":"10.1109/ISAM.2013.6643483","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643483","url":null,"abstract":"Atomic layer deposition (ALD) technology is a self-limiting ultrathin film deposition method. In ALD reactions, the reaction temperature plays a key role. And generalized predictive control (GPC) algorithm is adopted to control the temperature of a radiant heating reactor. The mathematical model of the system's temperature uniformity is calculated with heat transfer theory. Since temperature control is affected by GPC parameters including soften factor, weighting coefficient, sample time etc, it is necessary to study the effect of these parameters. By experiments, the values of soften factor, weighting coefficient and sampling time could be optimized and then be applied in the process of ALD reactions. And conclusions can be draw that soften factor has the largest impact on the algorithm while the influences of weighting coefficient and sampling time are almost negligible. Efficient temperature control of the ALD reactor chamber using GPC algorithm with optimal parameters is demonstrated.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128039133","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643458
Lin Wang, Shiyuan Pei, Hua Xu
In this study, a water-lubricated hybrid bearing with circumferential grooves and stepped recesses is devised for supporting a high-speed spindle system. Due to the low viscosity of water and high rotating speed, this hybrid bearing usually works in a turbulent regime. A computational procedure has been developed to calculate the bearing performance operating under different rotating speeds and supply pressures. The numerical model has taken turbulence and thermal effects into account. The results presented in this study is expected to be useful for the design of hybrid bearings. It will also be helpful to promote the future better test and safe operation of the high-speed spindle system for different machining processes.
{"title":"Infleence of rotating speed and supply pressure on the performance of water-lubricated hybrid bearing","authors":"Lin Wang, Shiyuan Pei, Hua Xu","doi":"10.1109/ISAM.2013.6643458","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643458","url":null,"abstract":"In this study, a water-lubricated hybrid bearing with circumferential grooves and stepped recesses is devised for supporting a high-speed spindle system. Due to the low viscosity of water and high rotating speed, this hybrid bearing usually works in a turbulent regime. A computational procedure has been developed to calculate the bearing performance operating under different rotating speeds and supply pressures. The numerical model has taken turbulence and thermal effects into account. The results presented in this study is expected to be useful for the design of hybrid bearings. It will also be helpful to promote the future better test and safe operation of the high-speed spindle system for different machining processes.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121368011","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 : 2013-10-24DOI: 10.1109/ISAM.2013.6643511
Song Changhui, Yang Yongqiang, Ye Ziheng, Wang Di
The theoretical models of the modern mechanism are becoming more difficult to be designed. The manufacturing feasibility largely constrains the design freedom. In order to liberate the design constraints of mechanisms and improve the innovation ability of the mechanical drive, in this paper, 3D CAD models which have been digital assembled and direct manufactured by selective laser melting are used to achieve non-assembly mechanisms. The clearance of the joint, the manufacturing direction and the manufacturing surface roughness are three important factors to be focused on in manufacturing metallic mechanism. Experiments verify that non-assembled metallic mechanisms can be manufactured by SLM, and have a certain mechanical bearing capacity. It provides a manufacturing method of choice for the development of mechatronics and MEMS.
{"title":"Digital design and direct manufacturing of non-assembly mechanisms by selective laser melting","authors":"Song Changhui, Yang Yongqiang, Ye Ziheng, Wang Di","doi":"10.1109/ISAM.2013.6643511","DOIUrl":"https://doi.org/10.1109/ISAM.2013.6643511","url":null,"abstract":"The theoretical models of the modern mechanism are becoming more difficult to be designed. The manufacturing feasibility largely constrains the design freedom. In order to liberate the design constraints of mechanisms and improve the innovation ability of the mechanical drive, in this paper, 3D CAD models which have been digital assembled and direct manufactured by selective laser melting are used to achieve non-assembly mechanisms. The clearance of the joint, the manufacturing direction and the manufacturing surface roughness are three important factors to be focused on in manufacturing metallic mechanism. Experiments verify that non-assembled metallic mechanisms can be manufactured by SLM, and have a certain mechanical bearing capacity. It provides a manufacturing method of choice for the development of mechatronics and MEMS.","PeriodicalId":323666,"journal":{"name":"2013 IEEE International Symposium on Assembly and Manufacturing (ISAM)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115901737","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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