Pub Date : 2008-07-13DOI: 10.1109/INDIN.2008.4618221
M. Shakeri, M. Low, Zhengping Li
Crossdocking is a just-in-time (JIT) practice in logistics of unloading materials from an incoming trailer and loading them into outgoing trailers, with little or no storage in between. The efficient operation of a crossdocking system requires an appropriate coordination of inbound and outbound flows, accurate planning and dynamic scheduling. Unfortunately, optimizing solutions to the problems associated with crossdock operational management and planning is quite difficult and in some cases even impossible. Besides, there is currently a shortage of planning policies for different crossdocking operations. In this paper, we develop a generic mathematical model to address the two problems of truck scheduling and truck-to-door assignment through employing a mixed integer programming approach (MIP). We believe our proposed model is generic enough to embrace various types of crossdocking operations which have been exercised in todaypsilas industrial world, more specifically fast moving consumer goods (FMCG) industry.
{"title":"A generic model for crossdock truck scheduling and truck-to-door assignment problems","authors":"M. Shakeri, M. Low, Zhengping Li","doi":"10.1109/INDIN.2008.4618221","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618221","url":null,"abstract":"Crossdocking is a just-in-time (JIT) practice in logistics of unloading materials from an incoming trailer and loading them into outgoing trailers, with little or no storage in between. The efficient operation of a crossdocking system requires an appropriate coordination of inbound and outbound flows, accurate planning and dynamic scheduling. Unfortunately, optimizing solutions to the problems associated with crossdock operational management and planning is quite difficult and in some cases even impossible. Besides, there is currently a shortage of planning policies for different crossdocking operations. In this paper, we develop a generic mathematical model to address the two problems of truck scheduling and truck-to-door assignment through employing a mixed integer programming approach (MIP). We believe our proposed model is generic enough to embrace various types of crossdocking operations which have been exercised in todaypsilas industrial world, more specifically fast moving consumer goods (FMCG) industry.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134415371","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618083
Jingmeng Liu, Whei-Jen Chen, Tianmiao Wang, Y. Ling
This paper presents the hardware design of three-axis NC system based on embedded system, designs the ARM (advanced RISC machine) + FPGA (field programmable gate array) hardware architecture, builds the software development environment, and accomplishes the communication program between ARM and FPGA. All of these provide excellent development platform for the application program developers. According to the requirement of three-axis NC system fine interpolation and complex I/O control, this paper accomplishes internal logic design of FPGA, realizes the fine interpolation pulse transmitting of NC system, receives the feedback pulse signal of encoder and extends many I/O ports to fulfills complex I/O control of three-axis NC system.
{"title":"Hardware circuit design of NC system based on ARM and FPGA","authors":"Jingmeng Liu, Whei-Jen Chen, Tianmiao Wang, Y. Ling","doi":"10.1109/INDIN.2008.4618083","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618083","url":null,"abstract":"This paper presents the hardware design of three-axis NC system based on embedded system, designs the ARM (advanced RISC machine) + FPGA (field programmable gate array) hardware architecture, builds the software development environment, and accomplishes the communication program between ARM and FPGA. All of these provide excellent development platform for the application program developers. According to the requirement of three-axis NC system fine interpolation and complex I/O control, this paper accomplishes internal logic design of FPGA, realizes the fine interpolation pulse transmitting of NC system, receives the feedback pulse signal of encoder and extends many I/O ports to fulfills complex I/O control of three-axis NC system.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125597028","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618239
Shurong Chen, Kai-yu Xu, Haiyun Gu
As one of critical devices of digital video surveillance system, Network Video Server (NVS) plays an important role by providing rich functionalities and high performances to better meet userspsila requirements. With rapid development of Digital Signal Processing (DSP) technology, performing high-quality MPEG4/H.264 video image codec in one DSP chip becomes possible. However, a majority of schemes of NVS are implemented via CPU and specific Audio/Video (AN) codec or DSP chip, which has distinct disadvantages in cost and product size. This paper presents design architecture for one-channel embedded NVS, which operates under dasiaRSIC plus DSPpsila mode of ADSP-BF561 chip with dual cores, and realizes video image coding based on MPEG4 with full D1 resolution, network transmitting, bidirectional speaking, and remote control functions, etc. Implementation methods of key modules are discussed, and performance indicators such as image quality over IP network and network delays are also verified in the end.
网络视频服务器(Network video Server, NVS)作为数字视频监控系统的关键设备之一，以其丰富的功能和高性能，更好地满足用户对视频监控的需求，发挥着重要的作用。随着数字信号处理(DSP)技术的飞速发展，实现高质量的MPEG4/H。在一个DSP芯片上实现264视频图像编解码成为可能。然而，大多数NVS方案都是通过CPU和特定的音频/视频(AN)编解码器或DSP芯片来实现的，这在成本和产品尺寸上有明显的缺点。本文提出了在ADSP-BF561双核芯片dasiaRSIC + DSPpsila模式下工作的单通道嵌入式NVS的设计架构，实现了基于MPEG4的全D1分辨率视频图像编码、网络传输、双向通话、远程控制等功能。讨论了关键模块的实现方法，并对IP网络图像质量、网络时延等性能指标进行了验证。
{"title":"Design of one-channel embedded Network Video Server","authors":"Shurong Chen, Kai-yu Xu, Haiyun Gu","doi":"10.1109/INDIN.2008.4618239","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618239","url":null,"abstract":"As one of critical devices of digital video surveillance system, Network Video Server (NVS) plays an important role by providing rich functionalities and high performances to better meet userspsila requirements. With rapid development of Digital Signal Processing (DSP) technology, performing high-quality MPEG4/H.264 video image codec in one DSP chip becomes possible. However, a majority of schemes of NVS are implemented via CPU and specific Audio/Video (AN) codec or DSP chip, which has distinct disadvantages in cost and product size. This paper presents design architecture for one-channel embedded NVS, which operates under dasiaRSIC plus DSPpsila mode of ADSP-BF561 chip with dual cores, and realizes video image coding based on MPEG4 with full D1 resolution, network transmitting, bidirectional speaking, and remote control functions, etc. Implementation methods of key modules are discussed, and performance indicators such as image quality over IP network and network delays are also verified in the end.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121174339","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618234
Hongzhe Jin, Jangmyung Lee
A new RMRAC (Robust Model Reference Adaptive Control) scheme for the PMSM (Permanent Magnet Synchronous Motor) current regulation is proposed in a synchronous frame which is completely free from the parameterpsilas uncertainty. A current regulator of PMSM is the inner most loop of electromechanical driving systems and plays a foundation role in the control hierarchy. When the PMSM runs in high speed, the cross-coupling terms must be compensated precisely for large system BW. In the proposed RMRAC, the input signal is composed of a calculated voltage defined by MRAC law and an output of the disturbance compensator. The gains of feed forward and feedback controller are estimated by the proposed modified gradient method, where the system disturbances are assumed as filtered current regulation errors. After the compensation of the system disturbance from error information, the corresponding voltage is fed forward to control input to compensate for real disturbances. The proposed method robustly compensates the system disturbance and cross-coupling term. It also shows a good real-time performance due to the simplicity of control structure. Through real experiments, the efficiency of the proposed method is verified.
{"title":"A novel adaptive current regulator for Permanent Magnet Synchronous Motor based on modified current dynamics","authors":"Hongzhe Jin, Jangmyung Lee","doi":"10.1109/INDIN.2008.4618234","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618234","url":null,"abstract":"A new RMRAC (Robust Model Reference Adaptive Control) scheme for the PMSM (Permanent Magnet Synchronous Motor) current regulation is proposed in a synchronous frame which is completely free from the parameterpsilas uncertainty. A current regulator of PMSM is the inner most loop of electromechanical driving systems and plays a foundation role in the control hierarchy. When the PMSM runs in high speed, the cross-coupling terms must be compensated precisely for large system BW. In the proposed RMRAC, the input signal is composed of a calculated voltage defined by MRAC law and an output of the disturbance compensator. The gains of feed forward and feedback controller are estimated by the proposed modified gradient method, where the system disturbances are assumed as filtered current regulation errors. After the compensation of the system disturbance from error information, the corresponding voltage is fed forward to control input to compensate for real disturbances. The proposed method robustly compensates the system disturbance and cross-coupling term. It also shows a good real-time performance due to the simplicity of control structure. Through real experiments, the efficiency of the proposed method is verified.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121272630","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618288
S. Hamasaki, T. Yakoh
A remote control system is one of the applications of communication. An user at a local side requires feedback information from a remote side to operate. In general, visual information and haptic information are used. However, it is impossible to synchronize local side and remote side perfectly because of communication delay and processing time. When the delay becomes long, the operability of remote control system becomes worse. To overcome this difficulty, this article proposed to introduce visual decorators, which are mainly researched in the field of virtual reality, in remote control system. The proposed decorators superimposed real-time remote side information on delayed remote video playout. A position decorator indicated the position of remote robot, and a force decorator indicated the force of the robot. Experimental results showed two decorators improve the operability of the remote control system over network with delay. This results confirmed the effectiveness of proposed decorators for remote control system with delayed video playout.
{"title":"Implementation and evaluation of decorators for delayed live streaming video on remote control system","authors":"S. Hamasaki, T. Yakoh","doi":"10.1109/INDIN.2008.4618288","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618288","url":null,"abstract":"A remote control system is one of the applications of communication. An user at a local side requires feedback information from a remote side to operate. In general, visual information and haptic information are used. However, it is impossible to synchronize local side and remote side perfectly because of communication delay and processing time. When the delay becomes long, the operability of remote control system becomes worse. To overcome this difficulty, this article proposed to introduce visual decorators, which are mainly researched in the field of virtual reality, in remote control system. The proposed decorators superimposed real-time remote side information on delayed remote video playout. A position decorator indicated the position of remote robot, and a force decorator indicated the force of the robot. Experimental results showed two decorators improve the operability of the remote control system over network with delay. This results confirmed the effectiveness of proposed decorators for remote control system with delayed video playout.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121314419","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618275
S. Seo, T. Moon, J.H. Kim, K. Kwon, J. Jeon, S.H. Hwang
This paper presents a fault-tolerant gateway embedded system that uses two micro-controllers. One microcontroller performs the main function of achieving a gateway, often called by the main micro-controller. In contrast, another plays the role of checker for the main micro-controller, and is called the sub micro-controller. To achieve fault-tolerance, the checker monitors the state of the main micro-controller. In this paper, we propose hardware architecture for fault-tolerance and evaluate the performance of the proposed system.
{"title":"A fault-tolerant gateway for in-vehicle networks","authors":"S. Seo, T. Moon, J.H. Kim, K. Kwon, J. Jeon, S.H. Hwang","doi":"10.1109/INDIN.2008.4618275","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618275","url":null,"abstract":"This paper presents a fault-tolerant gateway embedded system that uses two micro-controllers. One microcontroller performs the main function of achieving a gateway, often called by the main micro-controller. In contrast, another plays the role of checker for the main micro-controller, and is called the sub micro-controller. To achieve fault-tolerance, the checker monitors the state of the main micro-controller. In this paper, we propose hardware architecture for fault-tolerance and evaluate the performance of the proposed system.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121431751","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618321
Mai Thanh La, Q. Le, J. Jeon
This paper proposes an auto-tuning proportional-integral (PI) controller for the position control of a stepper motor. This method is based on a heuristic algorithm which finds the most suitable proportional and integral coefficients by testing the step responses of the system. Extra improvements can significantly reduce the number and interval of the testing steps, therefore minimizing the tuning time. The effectiveness of the new method is verified by experimental results.
{"title":"Effective auto-tuning Proportional-Integral controller based on a heuristic algorithm","authors":"Mai Thanh La, Q. Le, J. Jeon","doi":"10.1109/INDIN.2008.4618321","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618321","url":null,"abstract":"This paper proposes an auto-tuning proportional-integral (PI) controller for the position control of a stepper motor. This method is based on a heuristic algorithm which finds the most suitable proportional and integral coefficients by testing the step responses of the system. Extra improvements can significantly reduce the number and interval of the testing steps, therefore minimizing the tuning time. The effectiveness of the new method is verified by experimental results.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128459068","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618137
Kyoungtaik Park, Chanhun Park, Y. Shin
To experiment the performance characteristics of the developed dual-arm robot, the evaluation methods of motion characteristics of pose and path of dual-arm robot are studied and the results of performance evaluation are given. The evaluation method and item of motion performance such as payload, repeatability, maximum speed and position accuracy are studied and described. Because of the special provisions of repeatability of dual-arm robot are not given in ISO 9283, the evaluations of it are performed in based on the provisions of repeatability of single-arm robot. Generally, although there are no specifications of the position accuracy of robot movement, in this study the developed dual-arm robot is tested by using the provision of distance precision of ISO. Related to this, there are several problems of measurement of moving distance and definition of robot coordinate system. The evaluation method of payload is performed by measuring of the deflection of static payload because there is no special provision of payload in ISO. As there are no special provisions related to dual-arm robot in ISO 9283, the establishment of new provision of dual-arm robot is needed in near future.
{"title":"Performance test of industrial dual arm robot","authors":"Kyoungtaik Park, Chanhun Park, Y. Shin","doi":"10.1109/INDIN.2008.4618137","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618137","url":null,"abstract":"To experiment the performance characteristics of the developed dual-arm robot, the evaluation methods of motion characteristics of pose and path of dual-arm robot are studied and the results of performance evaluation are given. The evaluation method and item of motion performance such as payload, repeatability, maximum speed and position accuracy are studied and described. Because of the special provisions of repeatability of dual-arm robot are not given in ISO 9283, the evaluations of it are performed in based on the provisions of repeatability of single-arm robot. Generally, although there are no specifications of the position accuracy of robot movement, in this study the developed dual-arm robot is tested by using the provision of distance precision of ISO. Related to this, there are several problems of measurement of moving distance and definition of robot coordinate system. The evaluation method of payload is performed by measuring of the deflection of static payload because there is no special provision of payload in ISO. As there are no special provisions related to dual-arm robot in ISO 9283, the establishment of new provision of dual-arm robot is needed in near future.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115835108","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618355
Yi-Chun Lin, Feng‐Li Lian
In control design framework, the analysis on the stability and observability of a dynamic system is usually realized in the first place, and the quantity and quality of information exchanging is then considered in the second place. However, the interaction between information flow and system dynamics should be treated equally in real-world control applications. In this paper, the interaction lying between information constraint and dynamic behavior of a system is characterized. A framework with information flow and plant is proposed and related mathematical foundations are presented. In the end, three case studies: on-line interactive 3D video game, ball-camera system, and the location prediction of moving objects are shown.
{"title":"On characterizing the interaction between dynamical behavior and information flow in networked control","authors":"Yi-Chun Lin, Feng‐Li Lian","doi":"10.1109/INDIN.2008.4618355","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618355","url":null,"abstract":"In control design framework, the analysis on the stability and observability of a dynamic system is usually realized in the first place, and the quantity and quality of information exchanging is then considered in the second place. However, the interaction between information flow and system dynamics should be treated equally in real-world control applications. In this paper, the interaction lying between information constraint and dynamic behavior of a system is characterized. A framework with information flow and plant is proposed and related mathematical foundations are presented. In the end, three case studies: on-line interactive 3D video game, ball-camera system, and the location prediction of moving objects are shown.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115586937","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 : 2008-07-13DOI: 10.1109/INDIN.2008.4618149
Jian'an Xu, Mingjun Zhang
This paper investigates the application of neural network based generalized predictive motion control to an autonomous underwater vehicle. The modified Elman neural network is used as the multi-step predictive model, the fused identification model is proposed to improve the predictive and control precision. The modified Elman neural network on-line learning improves the control system adaptability to the unpredicted operating environment for autonomous underwater vehicle. Simulations on autonomous underwater vehicle yaw velocity control are included to illustrate the effectiveness of the proposed control scheme.
{"title":"Neural network modeling and generalized predictive control for an autonomous underwater vehicle","authors":"Jian'an Xu, Mingjun Zhang","doi":"10.1109/INDIN.2008.4618149","DOIUrl":"https://doi.org/10.1109/INDIN.2008.4618149","url":null,"abstract":"This paper investigates the application of neural network based generalized predictive motion control to an autonomous underwater vehicle. The modified Elman neural network is used as the multi-step predictive model, the fused identification model is proposed to improve the predictive and control precision. The modified Elman neural network on-line learning improves the control system adaptability to the unpredicted operating environment for autonomous underwater vehicle. Simulations on autonomous underwater vehicle yaw velocity control are included to illustrate the effectiveness of the proposed control scheme.","PeriodicalId":112553,"journal":{"name":"2008 6th IEEE International Conference on Industrial Informatics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114861095","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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