Pub Date : 1995-05-15DOI: 10.1109/RTTAS.1995.516206
Xiao-ge Huang, A. Cheng
One major requirement for multimedia systems is the efficient transmission of multimedia information over a communication or computer network. Current image/video transmission techniques works well if sufficient processing power and network bandwidth are available, but do not adapt properly to a reduction in one or more of these resources. This paper proposes an image/video transmission technique, based on the imprecise computation model, which yields a balanced tradeoff between the quality of the image/video transmitted and the available time for transmission. Our experiments show that the proposed algorithm has favorable results compared to non-imprecise computation-based algorithms.
{"title":"Applying imprecise algorithms to real-time image and video transmission","authors":"Xiao-ge Huang, A. Cheng","doi":"10.1109/RTTAS.1995.516206","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516206","url":null,"abstract":"One major requirement for multimedia systems is the efficient transmission of multimedia information over a communication or computer network. Current image/video transmission techniques works well if sufficient processing power and network bandwidth are available, but do not adapt properly to a reduction in one or more of these resources. This paper proposes an image/video transmission technique, based on the imprecise computation model, which yields a balanced tradeoff between the quality of the image/video transmitted and the available time for transmission. Our experiments show that the proposed algorithm has favorable results compared to non-imprecise computation-based algorithms.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116218626","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516215
A. Mehra, J. Rexford, F. Jahanian
Real-time applications typically operate under strict timing and dependability constraints. Although traditional data replication protocols provide fault tolerance, real-time guarantees require bounded overhead for managing this redundancy. This paper presents the design and evaluation of a window-consistent primary-backup replication service that provides timely availability of the repository by relaxing the consistency of the replicated data. The service guarantees controlled inconsistency by scheduling update transmissions from the primary to the backup(s); this ensures that client applications interact with a window-consistent repository when a backup must supplant a failed primary. Experiments on our prototype implementation show that the service handles a range of client loads while maintaining bounds on temporal inconsistency.
{"title":"Design and evaluation of a window-consistent replication service","authors":"A. Mehra, J. Rexford, F. Jahanian","doi":"10.1109/RTTAS.1995.516215","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516215","url":null,"abstract":"Real-time applications typically operate under strict timing and dependability constraints. Although traditional data replication protocols provide fault tolerance, real-time guarantees require bounded overhead for managing this redundancy. This paper presents the design and evaluation of a window-consistent primary-backup replication service that provides timely availability of the repository by relaxing the consistency of the replicated data. The service guarantees controlled inconsistency by scheduling update transmissions from the primary to the backup(s); this ensures that client applications interact with a window-consistent repository when a backup must supplant a failed primary. Experiments on our prototype implementation show that the service handles a range of client loads while maintaining bounds on temporal inconsistency.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116449419","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516221
K. M. Zuberi, K. Shin
Scheduling messages on the controller area network (CAN) corresponds to assigning identifiers (IDs) to messages according to their priorities. If fixed priority scheduling such as deadline monotonic (DM) is used to calculate these priorities, then in general, it will result in low schedulability. Dynamic scheduling schemes such as earliest deadline (ED) can give greater schedulability, but they are not practical for CAN because if the ID is to reflect message deadlines then a long ID must be used. This increases the length of each message to the point that ED is no better than DM. Our solution to this problem is the mixed traffic scheduler (MTS), which is a cross between ED and DM, and provides high schedulability without needing long IDs. Through simulations, we compare the performance of MTS with that of DM and ED* (an imaginary scheduler which works like ED, except it needs only short IDs). We use a realistic workload in our simulations based on messages typically found in computer integrated manufacturing. Our simulations show that MTS performs much better than DM and at the same level as ED*, except under high loads and tight deadlines, when ED* is superior.
在CAN (controller area network)上调度消息，就是按照消息的优先级为消息分配id。如果使用固定优先级调度(如截止时间单调调度(DM))来计算这些优先级，那么通常会导致较低的可调度性。诸如最早截止日期(ED)之类的动态调度方案可以提供更好的可调度性，但对于can来说并不实用，因为如果ID要反映消息截止日期，则必须使用长ID。这增加了每条消息的长度，以至于ED并不比DM好。我们对这个问题的解决方案是混合流量调度器(MTS)，它是ED和DM的交叉，提供了高可调度性，而不需要长id。通过仿真，我们将MTS的性能与DM和ED*(一种与ED类似的虚拟调度程序，除了它只需要短id)的性能进行了比较。我们在基于计算机集成制造中常见的消息的模拟中使用了一个真实的工作负载。我们的模拟表明，MTS的性能比DM好得多，与ED*的水平相同，但在高负载和紧迫的截止日期下，ED*优于MTS。
{"title":"Non-preemptive scheduling of messages on controller area network for real-time control applications","authors":"K. M. Zuberi, K. Shin","doi":"10.1109/RTTAS.1995.516221","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516221","url":null,"abstract":"Scheduling messages on the controller area network (CAN) corresponds to assigning identifiers (IDs) to messages according to their priorities. If fixed priority scheduling such as deadline monotonic (DM) is used to calculate these priorities, then in general, it will result in low schedulability. Dynamic scheduling schemes such as earliest deadline (ED) can give greater schedulability, but they are not practical for CAN because if the ID is to reflect message deadlines then a long ID must be used. This increases the length of each message to the point that ED is no better than DM. Our solution to this problem is the mixed traffic scheduler (MTS), which is a cross between ED and DM, and provides high schedulability without needing long IDs. Through simulations, we compare the performance of MTS with that of DM and ED* (an imaginary scheduler which works like ED, except it needs only short IDs). We use a realistic workload in our simulations based on messages typically found in computer integrated manufacturing. Our simulations show that MTS performs much better than DM and at the same level as ED*, except under high loads and tight deadlines, when ED* is superior.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126503618","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516205
C. Han, K. Shin
There has been an increasing need of timely and predictable communication services for embedded real-time systems in automated factories and industrial process controls. Work has been done on real-time communication with deadline guarantees in point-to-point, token bus/token ring/FDDI, and DQDB (Distributed Queue Dual Bus) networks. However, due to the random access nature of the CSMA/CD type multiaccess networks, they are not suitable for applications with stringent timing constraints. We consider real-time communication services with absolute deadline guarantees in multiaccess local area networks equipped with a centralized scheduler, such as the SP-50 FieldBus, an industrial standard protocol for process control and manufacturing applications. Similar to most token-passing networks, in a centralized scheduling multiaccess network, the access to the bus is controlled by a token. Only the station currently holding the token has the exclusive right to use the multiaccess bus. Unlike the token bus, token ring, or FDDI network, the multiaccess network uses a centralized token scheduling scheme and the token need not be allocated to the stations in a cyclic fashion. We show that the pinwheel and the distance-constrained scheduling techniques can be adapted to schedule the token in centralized-scheduling multiaccess networks to guarantee message deadlines.
{"title":"Real-time communication in FieldBus multiaccess networks","authors":"C. Han, K. Shin","doi":"10.1109/RTTAS.1995.516205","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516205","url":null,"abstract":"There has been an increasing need of timely and predictable communication services for embedded real-time systems in automated factories and industrial process controls. Work has been done on real-time communication with deadline guarantees in point-to-point, token bus/token ring/FDDI, and DQDB (Distributed Queue Dual Bus) networks. However, due to the random access nature of the CSMA/CD type multiaccess networks, they are not suitable for applications with stringent timing constraints. We consider real-time communication services with absolute deadline guarantees in multiaccess local area networks equipped with a centralized scheduler, such as the SP-50 FieldBus, an industrial standard protocol for process control and manufacturing applications. Similar to most token-passing networks, in a centralized scheduling multiaccess network, the access to the bus is controlled by a token. Only the station currently holding the token has the exclusive right to use the multiaccess bus. Unlike the token bus, token ring, or FDDI network, the multiaccess network uses a centralized token scheduling scheme and the token need not be allocated to the stations in a cyclic fashion. We show that the pinwheel and the distance-constrained scheduling techniques can be adapted to schedule the token in centralized-scheduling multiaccess networks to guarantee message deadlines.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133194324","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516220
Robert I. Davis, S. Punnekkat, N. Audsley, A. Burns
Complex real time systems, such as those envisaged for autonomous vehicle control, are expected to exhibit: adaptive and dynamic behaviour, resilience to software/hardware failures and graceful degradation, under conditions of overload. Two objectives need to be met before such properties can be realised. First, critical services must be guaranteed to provide results of a minimum acceptable quality and reliability by their deadlines. Second, the utility of the system needs to be maximised. We present an approach to meeting the above objectives. This approach combines the benefits of both fixed priority preemptive and best effort scheduling: offline analysis is used to guarantee that critical timing requirements will be met, whilst at run time, a simple adaptive threshold policy arbitrates between competing optional components, enhancing the system utility obtained.
{"title":"Flexible scheduling for adaptable real-time systems","authors":"Robert I. Davis, S. Punnekkat, N. Audsley, A. Burns","doi":"10.1109/RTTAS.1995.516220","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516220","url":null,"abstract":"Complex real time systems, such as those envisaged for autonomous vehicle control, are expected to exhibit: adaptive and dynamic behaviour, resilience to software/hardware failures and graceful degradation, under conditions of overload. Two objectives need to be met before such properties can be realised. First, critical services must be guaranteed to provide results of a minimum acceptable quality and reliability by their deadlines. Second, the utility of the system needs to be maximised. We present an approach to meeting the above objectives. This approach combines the benefits of both fixed priority preemptive and best effort scheduling: offline analysis is used to guarantee that critical timing requirements will be met, whilst at run time, a simple adaptive threshold policy arbitrates between competing optional components, enhancing the system utility obtained.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"105 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122634249","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516211
K. Nilsen, Hong Gao
Dynamic memory management is an important aspect of modern software engineering techniques based on object-oriented methodologies. Additionally, dynamic management of memory serves important roles in improving the flexibility and functionality of large software systems. However, developers of current real-time systems avoid the use of dynamic memory because they fear that the worst-case time and space requirements of typical dynamic memory managers are insufficiently bounded. The degree to which these concerns are valid is quantified by detailed measurements of several real-world workloads. A special hardware-assisted real-time garbage collection system has been designed to facilitate reliable use of dynamic memory in hard real-time systems. By analyzing the dynamic memory use of application software, the real-time developer can prove compliance with time and space constraints. Analysis techniques are presented and the real-time performance of the hardware-assisted garbage collection system is compared to that of the traditional allocators.
{"title":"The real-time behavior of dynamic memory management in C++","authors":"K. Nilsen, Hong Gao","doi":"10.1109/RTTAS.1995.516211","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516211","url":null,"abstract":"Dynamic memory management is an important aspect of modern software engineering techniques based on object-oriented methodologies. Additionally, dynamic management of memory serves important roles in improving the flexibility and functionality of large software systems. However, developers of current real-time systems avoid the use of dynamic memory because they fear that the worst-case time and space requirements of typical dynamic memory managers are insufficiently bounded. The degree to which these concerns are valid is quantified by detailed measurements of several real-world workloads. A special hardware-assisted real-time garbage collection system has been designed to facilitate reliable use of dynamic memory in hard real-time systems. By analyzing the dynamic memory use of application software, the real-time developer can prove compliance with time and space constraints. Analysis techniques are presented and the real-time performance of the hardware-assisted garbage collection system is compared to that of the traditional allocators.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133609087","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516217
T. Savor, R. Seviora
Software supervision is an approach to the real time detection of failures. A software supervisor is a unit which monitors both the inputs and outputs of a real time system and reports discrepancies between observed and expected behaviors. The major difficulty with software supervision is the running time complexity of the supervisor. A significant source of running time complexity was determined to be the total number of signals at the inputs queues of specification processes for which no ordering information is known. This paper describes an approach to reduce the running time complexity of a software supervisor. The approach makes use of a transformed specification in which several state transitions are grouped into a single transition or aggregate state. This effectively reduces the number of signals at the input queues of processes. The case where the system under supervision is specified in the ITU Specification and Description Language (SDL) is considered. An algorithm to translate SDL processes into aggregate state representations is described. Use of the algorithm is exemplified with the aid of an SDL specification of a small private branch telephone exchange.
{"title":"Improving the efficiency of supervision by software through state aggregation","authors":"T. Savor, R. Seviora","doi":"10.1109/RTTAS.1995.516217","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516217","url":null,"abstract":"Software supervision is an approach to the real time detection of failures. A software supervisor is a unit which monitors both the inputs and outputs of a real time system and reports discrepancies between observed and expected behaviors. The major difficulty with software supervision is the running time complexity of the supervisor. A significant source of running time complexity was determined to be the total number of signals at the inputs queues of specification processes for which no ordering information is known. This paper describes an approach to reduce the running time complexity of a software supervisor. The approach makes use of a transformed specification in which several state transitions are grouped into a single transition or aggregate state. This effectively reduces the number of signals at the input queues of processes. The case where the system under supervision is specified in the ITU Specification and Description Language (SDL) is considered. An algorithm to translate SDL processes into aggregate state representations is described. Use of the algorithm is exemplified with the aid of an SDL specification of a small private branch telephone exchange.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124649946","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516196
R. Mandler
CARTS is a set of system services targeted to real time distributed systems and spanning a variety of architectures. CARTS was designed to support rapid application code generation through generic user interfaces, to facilitate incremental system integration and reconfiguration via file-based data, and to provide tailored functionality appropriate to each project utilizing it. The CARTS postal system controls intertask communication within and between processors using optimal transfer methods such as shared memory, backplane I/O, or network I/O. The CARTS clock services supply high resolution time of day and mission clocks synchronized system wide at initialization and maintained through all levels of interface loading and across processor restarts.
{"title":"A configurable adjunct for real time systems (CARTS)","authors":"R. Mandler","doi":"10.1109/RTTAS.1995.516196","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516196","url":null,"abstract":"CARTS is a set of system services targeted to real time distributed systems and spanning a variety of architectures. CARTS was designed to support rapid application code generation through generic user interfaces, to facilitate incremental system integration and reconfiguration via file-based data, and to provide tailored functionality appropriate to each project utilizing it. The CARTS postal system controls intertask communication within and between processors using optimal transfer methods such as shared memory, backplane I/O, or network I/O. The CARTS clock services supply high resolution time of day and mission clocks synchronized system wide at initialization and maintained through all levels of interface loading and across processor restarts.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127104825","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516198
F. Hidano
Due to the availability in high-speed links and switches, real-time applications such as videoconferencing have gained the interest of researchers in the fields of multimedia and high-speed networking. Videoconferencing tools such as vic have been developed and tested on some of the ATM testbeds with no support for quality of service guarantees. Mechanisms for providing quality of service guarantees for these applications need to be supported. Extensive experiments are required to validate such mechanisms and it is vital to facilitate testbeds that enable these experiments. An important functionality in such testbeds is signalling support to establish virtual circuits. The direction of signalling is discussed and an example implementation from the XUNET testbed is described.
{"title":"Signalling on ATM testbeds: an example","authors":"F. Hidano","doi":"10.1109/RTTAS.1995.516198","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516198","url":null,"abstract":"Due to the availability in high-speed links and switches, real-time applications such as videoconferencing have gained the interest of researchers in the fields of multimedia and high-speed networking. Videoconferencing tools such as vic have been developed and tested on some of the ATM testbeds with no support for quality of service guarantees. Mechanisms for providing quality of service guarantees for these applications need to be supported. Extensive experiments are required to validate such mechanisms and it is vital to facilitate testbeds that enable these experiments. An important functionality in such testbeds is signalling support to establish virtual circuits. The direction of signalling is discussed and an example implementation from the XUNET testbed is described.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"373 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115895826","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 : 1995-05-15DOI: 10.1109/RTTAS.1995.516194
L. E. Heindel, V. Kasten
From the inception of real-time computing, there has been concern about the performance of disk I/O, especially as it relates to application filestores such as those running under variants of the UNIX operating system. We present a brief discussion of UNIX filestores and show how one can easily bound the number of physical file I/Os that the UNIX operating system must perform to execute a given application process. Using the established bound for the number of physical disk I/Os, one can develop close analytical approximations of application processes elapsed running time which is of critical importance for real-time applications.
{"title":"Real-time UNIX application filestores","authors":"L. E. Heindel, V. Kasten","doi":"10.1109/RTTAS.1995.516194","DOIUrl":"https://doi.org/10.1109/RTTAS.1995.516194","url":null,"abstract":"From the inception of real-time computing, there has been concern about the performance of disk I/O, especially as it relates to application filestores such as those running under variants of the UNIX operating system. We present a brief discussion of UNIX filestores and show how one can easily bound the number of physical file I/Os that the UNIX operating system must perform to execute a given application process. Using the established bound for the number of physical disk I/Os, one can develop close analytical approximations of application processes elapsed running time which is of critical importance for real-time applications.","PeriodicalId":265113,"journal":{"name":"Proceedings Real-Time Technology and Applications Symposium","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133049842","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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