Among various manual machine tool operations, it is known that the efficiency and accuracy of small-diameter deep-hole machining with a drilling machine is strongly dependent upon operator's sensitivity and skill learning level. In our previous work, a simulator of the drilling machine operation under no deflection of the drill was developed and its performance as a skill training apparatus was discussed. In this paper, the improvement of the simulator has been investigated. Firstly, the simulation model considering the deflection of the drill has been derived. Secondly, the model parameters have been reasonably identified from the experimental data of actual operation by applying the optimization technique due to genetic algorithm. In addition, the hardware system has been also improved to avoid reduction of realistic feeling which results from complicated calculation of the model.
{"title":"Drilling Machine Simulator Considering Deflection of Drill","authors":"W. Chen, H. Kato","doi":"10.2493/JJSPE.64.902","DOIUrl":"https://doi.org/10.2493/JJSPE.64.902","url":null,"abstract":"Among various manual machine tool operations, it is known that the efficiency and accuracy of small-diameter deep-hole machining with a drilling machine is strongly dependent upon operator's sensitivity and skill learning level. In our previous work, a simulator of the drilling machine operation under no deflection of the drill was developed and its performance as a skill training apparatus was discussed. In this paper, the improvement of the simulator has been investigated. Firstly, the simulation model considering the deflection of the drill has been derived. Secondly, the model parameters have been reasonably identified from the experimental data of actual operation by applying the optimization technique due to genetic algorithm. In addition, the hardware system has been also improved to avoid reduction of realistic feeling which results from complicated calculation of the model.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"9 1","pages":"203-208"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85428439","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}
In the end of World War II, Japanese industry of rolling bearings had disappeared because of bombing of the U.S.Air Force. In 1990's, about 30% of rolling bearings in the world are manufacturing by Japanese multinational bearing companies. The paper made clear the reasons why the acceptance of Japanese bearings to the world market after World War II. The reasons were the formation of production principles in Japanese manufacturers which depended deeply on Japanese people's national mentality came from their traditional sensitivity and perfectibility for artifacts. The production principles were to make low noise and vibration bearings, and long durability bearing. The paper deals with the processes, of technological progress of the bearings according to the principles, production technology and reliability assurance technology.
{"title":"Production principles of the rolling bearing industry in Japan after World War II","authors":"K. Kakuta","doi":"10.2493/JJSPE.64.99","DOIUrl":"https://doi.org/10.2493/JJSPE.64.99","url":null,"abstract":"In the end of World War II, Japanese industry of rolling bearings had disappeared because of bombing of the U.S.Air Force. In 1990's, about 30% of rolling bearings in the world are manufacturing by Japanese multinational bearing companies. The paper made clear the reasons why the acceptance of Japanese bearings to the world market after World War II. The reasons were the formation of production principles in Japanese manufacturers which depended deeply on Japanese people's national mentality came from their traditional sensitivity and perfectibility for artifacts. The production principles were to make low noise and vibration bearings, and long durability bearing. The paper deals with the processes, of technological progress of the bearings according to the principles, production technology and reliability assurance technology.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"1 1","pages":"43-48"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91222832","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}
In the present research corner wear of drills is measured automatically in order to predict end of drill life, using hole quality as criterion. Drilling experiments show a strong correlation between the progress of maximum hole diameter and hole surface roughness Ra over drill life. The proposed measurement system, using colour image processing and an artificial neural network, can detect corner wear of a drill accurately and predict the surface roughness Ra of the hole to be drilled with mean and maximum errors of 0.32μm and -1.00μm, respectively. The presence of a built-up edge does not influence the results.
{"title":"Automatic drill wear measurement using colour image processing and artificial neural network","authors":"U. Bopp, T. Sajima, H. Onikura","doi":"10.2493/JJSPE.64.1040","DOIUrl":"https://doi.org/10.2493/JJSPE.64.1040","url":null,"abstract":"In the present research corner wear of drills is measured automatically in order to predict end of drill life, using hole quality as criterion. Drilling experiments show a strong correlation between the progress of maximum hole diameter and hole surface roughness Ra over drill life. The proposed measurement system, using colour image processing and an artificial neural network, can detect corner wear of a drill accurately and predict the surface roughness Ra of the hole to be drilled with mean and maximum errors of 0.32μm and -1.00μm, respectively. The presence of a built-up edge does not influence the results.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"37 Suppl 7 1","pages":"287-292"},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78337341","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}
In order to improve the simulation system and to develop the control system with high performance, the dynamical model of the controlled object must precisely be derived. Ordinarily, the parameters are estimated by using the characteristic point data on the Bode diagram. As is well-known, this method is widely used in the production field. Meanwhile, the co-quad diagram based parameter estimation method was also known. It is said that this method can derive more precise modal parameters than the conventional method can. However, an explanation for the theoretical background is insufficient. In this paper, this reason is clarified by introducing the sensitivity function. Firstly the frequency response curve of both the Bode diagram and the co-quad diagram are shown for the compliance, the mobility, and the inertance. Next the parameter estimation formulas are derived by using the co-quad diagram. Secondly, by introducing the sensitivity function, it is shown that the co-quad based method has better performance from the parameter estimation point of view than the conventional one has. Finally, the parameter estimation method based on the co-quad diagram is applied to the measured inertance response and it is confirmed that the realistic parameters can derive in comparison with these from the Bode diagram.
{"title":"Relationship between parameter estimation method based on Bode diagram and co-quad diagram","authors":"S. Wakui","doi":"10.2493/JJSPE.63.570","DOIUrl":"https://doi.org/10.2493/JJSPE.63.570","url":null,"abstract":"In order to improve the simulation system and to develop the control system with high performance, the dynamical model of the controlled object must precisely be derived. Ordinarily, the parameters are estimated by using the characteristic point data on the Bode diagram. As is well-known, this method is widely used in the production field. Meanwhile, the co-quad diagram based parameter estimation method was also known. It is said that this method can derive more precise modal parameters than the conventional method can. However, an explanation for the theoretical background is insufficient. In this paper, this reason is clarified by introducing the sensitivity function. Firstly the frequency response curve of both the Bode diagram and the co-quad diagram are shown for the compliance, the mobility, and the inertance. Next the parameter estimation formulas are derived by using the co-quad diagram. Secondly, by introducing the sensitivity function, it is shown that the co-quad based method has better performance from the parameter estimation point of view than the conventional one has. Finally, the parameter estimation method based on the co-quad diagram is applied to the measured inertance response and it is confirmed that the realistic parameters can derive in comparison with these from the Bode diagram.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"1 1","pages":"227-231"},"PeriodicalIF":0.0,"publicationDate":"1997-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90761377","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}
An ultra-small sized actuator with high output torque at low rotation speed has been developed for applications to servo driving of micro-machines such as micro-robots. It consists of a micro-brushless DC motor, a planetary gear drive, and an optical rotary encoder. In this report, each element technology, output characteristics of the actuators and an application of the actuators to a micro-SCARA type robot are described. The brushless DC motor has a rotor with two poles of samarium cobalt magnets and three thin stator coils of fine copper wires. The planetary reduction gear drive has only six micro-gears with mechanical paradox. The optical rotary encoder has a metal circular scale with 75 slits and two optical glass fibers, and monitors rotation of the motor. Two prototypes of different sized actuators were developed: one is 3 mm in diameter and 10 mm in length, and the other is 5 mm in diameter and 18 mm in length, and were applied to a micro-SCARA type robot.
{"title":"Development of ultra-small sized servo actuator with brushless DC motor, planetary gear drive and optical rotary encoder","authors":"K. Hori, T. Miyagawa, Kenichi Ito","doi":"10.2493/JJSPE.63.1073","DOIUrl":"https://doi.org/10.2493/JJSPE.63.1073","url":null,"abstract":"An ultra-small sized actuator with high output torque at low rotation speed has been developed for applications to servo driving of micro-machines such as micro-robots. It consists of a micro-brushless DC motor, a planetary gear drive, and an optical rotary encoder. In this report, each element technology, output characteristics of the actuators and an application of the actuators to a micro-SCARA type robot are described. The brushless DC motor has a rotor with two poles of samarium cobalt magnets and three thin stator coils of fine copper wires. The planetary reduction gear drive has only six micro-gears with mechanical paradox. The optical rotary encoder has a metal circular scale with 75 slits and two optical glass fibers, and monitors rotation of the motor. Two prototypes of different sized actuators were developed: one is 3 mm in diameter and 10 mm in length, and the other is 5 mm in diameter and 18 mm in length, and were applied to a micro-SCARA type robot.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"41 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"1997-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76262857","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}
S. Hoyashita, M. Hashimoto, Kazuhiro Tanaka, Tomohiro Matsunoshita
A surface durability of case-carburized and hardened steel rollers is examined by a highly loaded two rollers contact fatigue testing machine. The surfaces of test rollers are finished to a surface roughness of about 3μmRmax by a cylindrical grinding machine. Thereafter, in order to improve the ground surface, the processes of shot peening, barrelling and hydraulic horning are employed. These processes can be applied to surfaces with complex configuration, such as gears. Each surface roughness of rollers finished by above machining processes is measured before/after running test, and residual stress in the vicinity of the surface of test pieces is also detected by an X-ray diffraction method. It is confirmed that the surface durability of rollers whose surfaces are subjected to the barrelling process after the shot-peening process is appreciably improved.
{"title":"Surface Improvement and Durability of Case-Carburized Gear - Results of Basic Rollers Running Test -","authors":"S. Hoyashita, M. Hashimoto, Kazuhiro Tanaka, Tomohiro Matsunoshita","doi":"10.2493/JJSPE.63.259","DOIUrl":"https://doi.org/10.2493/JJSPE.63.259","url":null,"abstract":"A surface durability of case-carburized and hardened steel rollers is examined by a highly loaded two rollers contact fatigue testing machine. The surfaces of test rollers are finished to a surface roughness of about 3μmRmax by a cylindrical grinding machine. Thereafter, in order to improve the ground surface, the processes of shot peening, barrelling and hydraulic horning are employed. These processes can be applied to surfaces with complex configuration, such as gears. Each surface roughness of rollers finished by above machining processes is measured before/after running test, and residual stress in the vicinity of the surface of test pieces is also detected by an X-ray diffraction method. It is confirmed that the surface durability of rollers whose surfaces are subjected to the barrelling process after the shot-peening process is appreciably improved.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"80 1","pages":"33-38"},"PeriodicalIF":0.0,"publicationDate":"1997-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89151476","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}
In general, many processes are required to produce precision dies and molds, including cutting, electrical discharge machining, grinding and polishing. In particular, since cutting with small-diameter tools on current machines is difficult for extra-small precision dies and molds, productivity and precision are extremely low. This research project involved the creation of new machining technology for the use of small-diameter tools, and the development of machine tools capable of streamlining the machining processes while maintaining consistent quality, with the ultimate goal being to reduce die/mold lead times while decreasing cost. The project resulted in an increase in production efficiency of between two to five times for actual machining applications, with efficiency being boosted over tenfold on applications most suited to the new technique.
{"title":"Development of High-Productivity Machine for Precision Dies and Molds","authors":"K. Utsumi, Hideki Mochida","doi":"10.2493/JJSPE.63.1077","DOIUrl":"https://doi.org/10.2493/JJSPE.63.1077","url":null,"abstract":"In general, many processes are required to produce precision dies and molds, including cutting, electrical discharge machining, grinding and polishing. In particular, since cutting with small-diameter tools on current machines is difficult for extra-small precision dies and molds, productivity and precision are extremely low. This research project involved the creation of new machining technology for the use of small-diameter tools, and the development of machine tools capable of streamlining the machining processes while maintaining consistent quality, with the ultimate goal being to reduce die/mold lead times while decreasing cost. The project resulted in an increase in production efficiency of between two to five times for actual machining applications, with efficiency being boosted over tenfold on applications most suited to the new technique.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"12 1","pages":"6-9"},"PeriodicalIF":0.0,"publicationDate":"1997-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86178068","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}
K. Yasutake, A. Takeuchi, H. Kakiuchi, Y. Okuyama, K. Yoshii, H. Kawabe
InGaAs/GaAs strained-layer single quantum well (SSQW) structures have been grown at temperatures from 200 to 540°C by migration enhanced epitaxy (MEE). Fabricated structures were characterized by comparing the measured wavelength of photoluminescence (PL) emission peak with the theoretically calculated one for ideal quantum wells. In the SSQWs made at high temperatures (400 - 540°C), large PL peak shifts to the shorter wavelengths than the calculated ones were observed. This blue shift of the PL peak was attributed to the surface segregation and desorption of In atoms. Lowering the growth temperature of MEE below 300°C, the In segregation was suppressed and the designed PL wavelength from the SSQW was obtained. It was shown that the preparation of GaAs (2 × 4) -As surface without excess Assticking and the long migration time of group III atoms were needed to obtain the high PL intensity from SSQW.
{"title":"Low temperature growth of InGaAs/GaAs strained-layer single quantum wells","authors":"K. Yasutake, A. Takeuchi, H. Kakiuchi, Y. Okuyama, K. Yoshii, H. Kawabe","doi":"10.2493/JJSPE.63.60","DOIUrl":"https://doi.org/10.2493/JJSPE.63.60","url":null,"abstract":"InGaAs/GaAs strained-layer single quantum well (SSQW) structures have been grown at temperatures from 200 to 540°C by migration enhanced epitaxy (MEE). Fabricated structures were characterized by comparing the measured wavelength of photoluminescence (PL) emission peak with the theoretically calculated one for ideal quantum wells. In the SSQWs made at high temperatures (400 - 540°C), large PL peak shifts to the shorter wavelengths than the calculated ones were observed. This blue shift of the PL peak was attributed to the surface segregation and desorption of In atoms. Lowering the growth temperature of MEE below 300°C, the In segregation was suppressed and the designed PL wavelength from the SSQW was obtained. It was shown that the preparation of GaAs (2 × 4) -As surface without excess Assticking and the long migration time of group III atoms were needed to obtain the high PL intensity from SSQW.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"312 1","pages":"47-52"},"PeriodicalIF":0.0,"publicationDate":"1997-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80024205","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}
An intelligent vibration gripper has been developed. The gripper can handle an object of unknown weight and unknown surface condition with the most suitable grasping force. Additionally, the gripper can adapt the grasping force to the most suitable value for the object even if the weight or the surface conditions of the object change. The gripper has two parallel fingers. Each finger is composed of a mechanical vibration system having two degrees of freedom. The system consists of a main mass block and an oscillator block, and these blocks are connected by two springs. In the main mass block, a harmonic force is always generated and absorbed by a dynamic damper consisting of the oscillator block and a spring, so that the main mass block is kept in a stationary condition and the oscillator block vibrates with a constant amplitude. The object is grasped between both the main mass blocks. When the object is grasped with the most suitable grasping force, not only the object and both main mass blocks become stationary but also both oscillator blocks become stationary because harmonic forces are transmitted to the object from each main mass block and the two harmonic forces cancel each other out. In this gripper, the grasping force is adjusted to the most suitable value as the amplitudes of both oscillator blocks are reduced to zero. This paper describes a fundamental principle of this intelligent gripper and the principle is confirmed by experiment.
{"title":"Development of an Intelligent Gripper with a Dynamic Vibration Absorber","authors":"S. Honda","doi":"10.2493/JJSPE.63.824","DOIUrl":"https://doi.org/10.2493/JJSPE.63.824","url":null,"abstract":"An intelligent vibration gripper has been developed. The gripper can handle an object of unknown weight and unknown surface condition with the most suitable grasping force. Additionally, the gripper can adapt the grasping force to the most suitable value for the object even if the weight or the surface conditions of the object change. The gripper has two parallel fingers. Each finger is composed of a mechanical vibration system having two degrees of freedom. The system consists of a main mass block and an oscillator block, and these blocks are connected by two springs. In the main mass block, a harmonic force is always generated and absorbed by a dynamic damper consisting of the oscillator block and a spring, so that the main mass block is kept in a stationary condition and the oscillator block vibrates with a constant amplitude. The object is grasped between both the main mass blocks. When the object is grasped with the most suitable grasping force, not only the object and both main mass blocks become stationary but also both oscillator blocks become stationary because harmonic forces are transmitted to the object from each main mass block and the two harmonic forces cancel each other out. In this gripper, the grasping force is adjusted to the most suitable value as the amplitudes of both oscillator blocks are reduced to zero. This paper describes a fundamental principle of this intelligent gripper and the principle is confirmed by experiment.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"114 1","pages":"63-67"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76385649","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}
K. Nagasaka, Yoshiaki Kitaguchi, A. Matsubara, I. Yamaji, Y. Kakino, H. Nakagawa, Y. Kita
Kazunori Nagasaka, Yoshiaki KITAGUCHI, Atsushi MATSUBARA, Iwao YAMAJI, Yoshiaki KAKINO, Heisaburou NAKAGAWA and Yoshihiro KITA This paper treats the construction of expert system for process planning in grinding. The grinding wheels are standardized and the definition of shape elements is simplified. From the rules of tool selection and processing order for each reference surface, the computer program for determination of the order of grinding is executed. In the system, the initial data are input through the data base software on the market, and the solution of the grinding order of a given part is determined for various reference surfaces. The confirmation of the effectiveness of the system is shown by an example.
{"title":"The Development of Expert System for Process Planning in Grinding with Grinding Center","authors":"K. Nagasaka, Yoshiaki Kitaguchi, A. Matsubara, I. Yamaji, Y. Kakino, H. Nakagawa, Y. Kita","doi":"10.2493/JJSPE.63.1007","DOIUrl":"https://doi.org/10.2493/JJSPE.63.1007","url":null,"abstract":"Kazunori Nagasaka, Yoshiaki KITAGUCHI, Atsushi MATSUBARA, Iwao YAMAJI, Yoshiaki KAKINO, Heisaburou NAKAGAWA and Yoshihiro KITA This paper treats the construction of expert system for process planning in grinding. The grinding wheels are standardized and the definition of shape elements is simplified. From the rules of tool selection and processing order for each reference surface, the computer program for determination of the order of grinding is executed. In the system, the initial data are input through the data base software on the market, and the solution of the grinding order of a given part is determined for various reference surfaces. The confirmation of the effectiveness of the system is shown by an example.","PeriodicalId":14336,"journal":{"name":"International Journal of The Japan Society for Precision Engineering","volume":"67 1","pages":"260-266"},"PeriodicalIF":0.0,"publicationDate":"1997-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73385620","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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