Pub Date : 2020-08-31DOI: 10.17958/KSMT.22.4.202008.667
Sim choong-gun
전기장에 의해 생성 된 진공 분극은 양자장에서 가상 전자-양전자 쌍의 재배열을 만든다. 그러나 정지 전하가 다른 장소로 이동할 때, 정지 전하에 의해 생성된 전기장은 사라질 것이다. 이때, 정지 전하에 의해 분극화된 가상 전자-양전자 쌍들은 같이 소멸된다. 가상 전자-양전자의 소멸 과정에서 가상 광자가 생성되는데, 이때 만들어지는 가상 광자들은 양자 전기 역학에서 자기력을 매개하는 광자가 된다. 이로 인하여, 전하의 이동은 자기장을 발생시키고, 전기장의 변화가 자기장을 생성하게 하는 원인이 된다.
{"title":"Why Does a Changing Electric Field Create a Magnetic Field","authors":"Sim choong-gun","doi":"10.17958/KSMT.22.4.202008.667","DOIUrl":"https://doi.org/10.17958/KSMT.22.4.202008.667","url":null,"abstract":"전기장에 의해 생성 된 진공 분극은 양자장에서 가상 전자-양전자 쌍의 재배열을 만든다. 그러나 정지 전하가 다른 장소로 이동할 때, 정지 전하에 의해 생성된 전기장은 사라질 것이다. 이때, 정지 전하에 의해 분극화된 가상 전자-양전자 쌍들은 같이 소멸된다. 가상 전자-양전자의 소멸 과정에서 가상 광자가 생성되는데, 이때 만들어지는 가상 광자들은 양자 전기 역학에서 자기력을 매개하는 광자가 된다. 이로 인하여, 전하의 이동은 자기장을 발생시키고, 전기장의 변화가 자기장을 생성하게 하는 원인이 된다.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130713830","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.37
강환국, 김대영
Experiments were conducted on the operating characteristics and performance of various types of working fluid, filling amount and heat flow rate of a loop thermosyphon for cooling ESS battery container. As results of performance test on various working fluids, HFE-7100 and R-134a as a working fluids showed unstable operating and low performance due to vapor pressure drop, and performance was improved by increasing the number of vapor lines for reducing a pressure drop. In this study, n-pentane was more stable and showed better thermal performance among various working fluids.
{"title":"ESS 컨테이너 냉각용 루프 열사이폰 열교환기의 다양한 작동유체에 대한 특성과 성능 실험","authors":"강환국, 김대영","doi":"10.17958/ksmt.22.1.202002.37","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.37","url":null,"abstract":"Experiments were conducted on the operating characteristics and performance of various types of working fluid, filling amount and heat flow rate of a loop thermosyphon for cooling ESS battery container. As results of performance test on various working fluids, HFE-7100 and R-134a as a working fluids showed unstable operating and low performance due to vapor pressure drop, and performance was improved by increasing the number of vapor lines for reducing a pressure drop. In this study, n-pentane was more stable and showed better thermal performance among various working fluids.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129633039","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.19
안태원
Generally, vibration absorber systems are composed of spring-mass systems to reduce the vibration of a structure, and there are also methods to simply increase damping to achieve a damping effect across a wide frequency band. One similar method is to use a mechanism in which the eddy current is converted into a mechanical damping effect. When an eddy current is generated by electromotive force due to magnetic flux change, the reaction force is generated by the eddy current’s circulation. In this study, the damping system using the reaction force was constructed to reduce the transmission of vibrations generating from internal fluid and the vibration reduction characteristics that are transmitted externally were analyzed. As a result, 8.2 % of the vibration reduction effect from primary excitation frequency was confirmed.
{"title":"Eddy Current Damping System의 진동 저감 특성 평가","authors":"안태원","doi":"10.17958/ksmt.22.1.202002.19","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.19","url":null,"abstract":"Generally, vibration absorber systems are composed of spring-mass systems to reduce the vibration of a structure, and there are also methods to simply increase damping to achieve a damping effect across a wide frequency band. One similar method is to use a mechanism in which the eddy current is converted into a mechanical damping effect. When an eddy current is generated by electromotive force due to magnetic flux change, the reaction force is generated by the eddy current’s circulation. In this study, the damping system using the reaction force was constructed to reduce the transmission of vibrations generating from internal fluid and the vibration reduction characteristics that are transmitted externally were analyzed. As a result, 8.2 % of the vibration reduction effect from primary excitation frequency was confirmed.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"2 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113938738","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.30
Sung-Hak Bae, Kim Pilkee
In this study, a bistable energy harvester (BEH) with a piecewise potential function is proposed to improve its energy harvesting performance. A mathematical model of the piecewise BEH (PWBEH) system is established first and a series of numerical simulation are performed, based on the developed model, in order to investigate the nonlinear dynamic behaviors and energy-harvesting performance of the system. The analysis results for the proposed PWBEH system are compared with a conventional BEH (CBEH). The frequency response results show the stiffness-softening interwell motion of the PWBEH, due to the piecewise potential energy function, which is contrary to the stiffness-hardening behavior of the CBEH. Such softening behavior of interwell motion tends to reduce the operating frequency of the BEH, while significantly increasing the output power. This observation indicate that the introduction of the piecewise potential function to a BEH would be beneficial to the system design for enhancing enegy-harvesting performance at the cost of redundant frequency band, which depends on the characteristics of environmental vibration sources.
{"title":"Piecewise Potential Function을 갖는 쌍안정 에너지 수확기의 비선형 동특성 해석","authors":"Sung-Hak Bae, Kim Pilkee","doi":"10.17958/ksmt.22.1.202002.30","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.30","url":null,"abstract":"In this study, a bistable energy harvester (BEH) with a piecewise potential function is proposed to improve its energy harvesting performance. A mathematical model of the piecewise BEH (PWBEH) system is established first and a series of numerical simulation are performed, based on the developed model, in order to investigate the nonlinear dynamic behaviors and energy-harvesting performance of the system. The analysis results for the proposed PWBEH system are compared with a conventional BEH (CBEH). The frequency response results show the stiffness-softening interwell motion of the PWBEH, due to the piecewise potential energy function, which is contrary to the stiffness-hardening behavior of the CBEH. Such softening behavior of interwell motion tends to reduce the operating frequency of the BEH, while significantly increasing the output power. This observation indicate that the introduction of the piecewise potential function to a BEH would be beneficial to the system design for enhancing enegy-harvesting performance at the cost of redundant frequency band, which depends on the characteristics of environmental vibration sources.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131660646","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.84
Choi，Young-Kiu, Park，Jin-Hyun
This paper deals with the dynamic control of redundant robot manipulator. Traditionally, the kinematic control schemes for redundant robot manipulator were developed from the point of speed and used under the assumption that the dynamic control of manipulator is perfect. However, in reality, the precise control of redundant robot manipulator is very difficult due to their dynamics. Therefore, the kinematic controllers for redundant robot manipulator were employed in the acceleration dimension and may be combined with the computed torque method to achieve the accurate control performance. But their control performance is limited by the accuracy of the manipulator parameters such as the link mass, length, moment of inertia and varying payload. Hence in this paper, the proportional and derivative control gains of the computed torque controller are optimized by the genetic algorithm on the typical payloads, and the neural network is applied to obtain the proper control gains for arbitrary loads. The simulation results show that the proposed control method has better performance than the conventional control method for redundant robot manipulator.
{"title":"여유자유도 로봇 매니퓰레이터를 위한 동적제어시스템","authors":"Choi，Young-Kiu, Park，Jin-Hyun","doi":"10.17958/ksmt.22.1.202002.84","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.84","url":null,"abstract":"This paper deals with the dynamic control of redundant robot manipulator. Traditionally, the kinematic control schemes for redundant robot manipulator were developed from the point of speed and used under the assumption that the dynamic control of manipulator is perfect. However, in reality, the precise control of redundant robot manipulator is very difficult due to their dynamics. Therefore, the kinematic controllers for redundant robot manipulator were employed in the acceleration dimension and may be combined with the computed torque method to achieve the accurate control performance. But their control performance is limited by the accuracy of the manipulator parameters such as the link mass, length, moment of inertia and varying payload. Hence in this paper, the proportional and derivative control gains of the computed torque controller are optimized by the genetic algorithm on the typical payloads, and the neural network is applied to obtain the proper control gains for arbitrary loads. The simulation results show that the proposed control method has better performance than the conventional control method for redundant robot manipulator.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133265659","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 : 2020-02-29DOI: 10.17958/KSMT.22.1.202002.1
김병삼, 박진영, 서양, 김정기, 이원형, 이경훈
Recently, as the quality of life of modern people improves, interest in environmental noise is gradually increasing. As the public's awareness of environmental rights increased, it was necessary to grasp the actual condition of the noise source and systematic noise management plan. The data is expected to be used as a response to noise-related complaints. As a result measured using the factory noise monitoring system, the amount of data measured every 5 minutes from 00:00 to 24:00 can obtain 288 noise levels and frequency characteristics per day, and frequency using 1/3 octave-band. The analysis reveals what frequency range affects the noise from the metal working plant near the office. In addition, it can be seen that it is possible to compare with the reference value by using the stored data divided into night time, day time, and evening time for each time zone, and it is determined that it is possible to secure smooth data about the noise source to be measured.
{"title":"금속재료품 제조공장의 소음 모니터링 시스템","authors":"김병삼, 박진영, 서양, 김정기, 이원형, 이경훈","doi":"10.17958/KSMT.22.1.202002.1","DOIUrl":"https://doi.org/10.17958/KSMT.22.1.202002.1","url":null,"abstract":"Recently, as the quality of life of modern people improves, interest in environmental noise is gradually increasing. As the public's awareness of environmental rights increased, it was necessary to grasp the actual condition of the noise source and systematic noise management plan. The data is expected to be used as a response to noise-related complaints. As a result measured using the factory noise monitoring system, the amount of data measured every 5 minutes from 00:00 to 24:00 can obtain 288 noise levels and frequency characteristics per day, and frequency using 1/3 octave-band. The analysis reveals what frequency range affects the noise from the metal working plant near the office. In addition, it can be seen that it is possible to compare with the reference value by using the stored data divided into night time, day time, and evening time for each time zone, and it is determined that it is possible to secure smooth data about the noise source to be measured.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126586928","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.52
Tae-Keun Lee, 이영욱, Kim Byoung-sam
In the car speaker, because the sound characteristics is changed by the space of car which mount the speaker, the speaker elements must be decide according to sound field. In this study, the nonlinear characteristics, the frequency response and the sound pressure for the same size speakers which is adapted to domestic car model are investigated. The car model is classified to semi-midsize, midsized, full size automobile in order to change the car space. As a results, we can investigate the differences of the force factor and the stiffness of suspension system for speaker. According to the change of the speaker characteristics, the sound pressure is changed, also. In the future, these data will be used to investigate the correlation between the sound quality and measurement data.
{"title":"차종별 우퍼 스피커의 특성에 관한 연구","authors":"Tae-Keun Lee, 이영욱, Kim Byoung-sam","doi":"10.17958/ksmt.22.1.202002.52","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.52","url":null,"abstract":"In the car speaker, because the sound characteristics is changed by the space of car which mount the speaker, the speaker elements must be decide according to sound field. In this study, the nonlinear characteristics, the frequency response and the sound pressure for the same size speakers which is adapted to domestic car model are investigated. The car model is classified to semi-midsize, midsized, full size automobile in order to change the car space. As a results, we can investigate the differences of the force factor and the stiffness of suspension system for speaker. According to the change of the speaker characteristics, the sound pressure is changed, also. In the future, these data will be used to investigate the correlation between the sound quality and measurement data.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134154454","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.24
송준혁
Since electric energy is used in industry, mass production and various conveniences are provided. To provide convenience for the construction and operation of such electric energy transmission and distribution facilities, it is increasing that the demand for special purpose vehicles, that is, telescopic aerial work platform vehicles. When working active electric work using the telescopic aerial work platform vehicles, due to active electric work is inevitable, it is essential to ensure insulation performance for the safety of the operator. In this paper, we study the design and development of mechanical properties for filament winding process of glassfiber/epoxy composite, it is required to boom of telescopic aerial work platform vehicles. The glass fiber/epoxy composite filament winding process and its mechanical properties were evaluated to replace the existing ATOS80 boom. By filament winding process it was obtained the mechanical properties required for the design analysis of the glass fiber/epoxy composite boom. Using this, the insulated boom for the 30m class aerial work vehicle was designed and was manufactured by applying the filament winding process. The fabricated composite boom was evaluated by the static strength test to meet the required strength. The maximum displacement was 84mm and the crack occurred at the maximum load of 8981N. It satisfied the maximum lifting load of 4900N and 210mm the maximum displacement required for the boom.
{"title":"필라멘트 와인딩 공법에 의한 30m급 굴절형 고소작업차용 유리섬유/에폭시 복합재 붐 개발에 관한 연구","authors":"송준혁","doi":"10.17958/ksmt.22.1.202002.24","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.24","url":null,"abstract":"Since electric energy is used in industry, mass production and various conveniences are provided. To provide convenience for the construction and operation of such electric energy transmission and distribution facilities, it is increasing that the demand for special purpose vehicles, that is, telescopic aerial work platform vehicles. When working active electric work using the telescopic aerial work platform vehicles, due to active electric work is inevitable, it is essential to ensure insulation performance for the safety of the operator. In this paper, we study the design and development of mechanical properties for filament winding process of glassfiber/epoxy composite, it is required to boom of telescopic aerial work platform vehicles. The glass fiber/epoxy composite filament winding process and its mechanical properties were evaluated to replace the existing ATOS80 boom. By filament winding process it was obtained the mechanical properties required for the design analysis of the glass fiber/epoxy composite boom. Using this, the insulated boom for the 30m class aerial work vehicle was designed and was manufactured by applying the filament winding process. The fabricated composite boom was evaluated by the static strength test to meet the required strength. The maximum displacement was 84mm and the crack occurred at the maximum load of 8981N. It satisfied the maximum lifting load of 4900N and 210mm the maximum displacement required for the boom.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114244671","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.12
Lee Tae Hwan, Park，Jin-Hyun
The flow analysis of two dimensional transient flow over the obstacles with rectangular cross sections was performed. And 190 velocity distributions for each aspect ratio were imaged to provide input data for convolutional neural network learning. The classification and regression methods were used in estimating the aspect ratio from given velocity distributions. As a result the classification method was more exact than the regression method. But both the classification and regression methods gave relatively accurate prediction of the defined aspect ratio judging from the imaged velocity distributions. This confirms that the deep learning technique is applicable to the flow analysis.
{"title":"딥러닝 기법을 사용한 이차원 과도유동 해석","authors":"Lee Tae Hwan, Park，Jin-Hyun","doi":"10.17958/ksmt.22.1.202002.12","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.12","url":null,"abstract":"The flow analysis of two dimensional transient flow over the obstacles with rectangular cross sections was performed. And 190 velocity distributions for each aspect ratio were imaged to provide input data for convolutional neural network learning. The classification and regression methods were used in estimating the aspect ratio from given velocity distributions. As a result the classification method was more exact than the regression method. But both the classification and regression methods gave relatively accurate prediction of the defined aspect ratio judging from the imaged velocity distributions. This confirms that the deep learning technique is applicable to the flow analysis.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128963384","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 : 2020-02-29DOI: 10.17958/ksmt.22.1.202002.44
한석종, 박다인, Sang-ho Lee
Numerical analysis has been carried out to analyze seawater flow field and power generation characteristics of the tidal current power generation system for various multi channel shroud systems. Geometrical multi channel arrangement largely affects the flow field characteristics in the shroud system which power generation performance through turbine blade depends on. Sectional averaged velocity in front of the turbine blade which increases more than 2 times compared with channel inlet is much influenced as well as the flow from the rear with curl. And flow variation results in high inlet velocity in horizontal arrangements of multi channels with mechanical output of the turbine. These results are expected to be used as applicable data for the development of the tidal power generation system with shrouds.
{"title":"쉬라우드형 조류발전 시스템의 다중 채널구조에 따른 해수유동장 분석","authors":"한석종, 박다인, Sang-ho Lee","doi":"10.17958/ksmt.22.1.202002.44","DOIUrl":"https://doi.org/10.17958/ksmt.22.1.202002.44","url":null,"abstract":"Numerical analysis has been carried out to analyze seawater flow field and power generation characteristics of the tidal current power generation system for various multi channel shroud systems. Geometrical multi channel arrangement largely affects the flow field characteristics in the shroud system which power generation performance through turbine blade depends on. Sectional averaged velocity in front of the turbine blade which increases more than 2 times compared with channel inlet is much influenced as well as the flow from the rear with curl. And flow variation results in high inlet velocity in horizontal arrangements of multi channels with mechanical output of the turbine. These results are expected to be used as applicable data for the development of the tidal power generation system with shrouds.","PeriodicalId":168106,"journal":{"name":"Journal of the Korean Society of Mechanical Technology","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125545792","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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