3D stacking is currently seen as a breakthrough technology for improving bandwidth and energy efficiency in multi-core architectures. The expectation is to solve major issues such as external memory pressure and latency while maintaining reasonable power consumption. In this paper, we show some advances in this field of research, starting with memory interface solutions as WIDEIO experience on a real chip for solving DRAM accesses issue. We explain the integration of a 512-bit memory interface in a Network-on-Chip multi-core framework and we show the performance we can achieve, these results being based on a 65nm prototype integrating 10µm diameter Through Silicon Vias. We then present the potentiality of new fine grain 3D stacking technology for power-efficient memory hierarchy. We expose an innovative 3D stacked multi-cache strategy aimed at lowering memory latency and external memory bandwidth requirements and thus demonstrating the efficiency of 3D stacking to rethink architectures for obtaining unequalled performances in power efficiency.
{"title":"3D integration for power-efficient computing","authors":"D. Dutoit, E. Guthmuller, I. Panades","doi":"10.7873/DATE.2013.166","DOIUrl":"https://doi.org/10.7873/DATE.2013.166","url":null,"abstract":"3D stacking is currently seen as a breakthrough technology for improving bandwidth and energy efficiency in multi-core architectures. The expectation is to solve major issues such as external memory pressure and latency while maintaining reasonable power consumption. In this paper, we show some advances in this field of research, starting with memory interface solutions as WIDEIO experience on a real chip for solving DRAM accesses issue. We explain the integration of a 512-bit memory interface in a Network-on-Chip multi-core framework and we show the performance we can achieve, these results being based on a 65nm prototype integrating 10µm diameter Through Silicon Vias. We then present the potentiality of new fine grain 3D stacking technology for power-efficient memory hierarchy. We expose an innovative 3D stacked multi-cache strategy aimed at lowering memory latency and external memory bandwidth requirements and thus demonstrating the efficiency of 3D stacking to rethink architectures for obtaining unequalled performances in power efficiency.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81380061","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}
Liangzhen Lai, V. Chandra, R. Aitken, Puneet Gupta
In situ monitoring is an accurate way to monitor circuit delay or timing slack, but usually incurs significant overhead. We observe that most existing slack monitoring methods exclusively focus on monitoring path ending registers, which is not cost efficient from power and area perspectives.
{"title":"SlackProbe: A low overhead in situ on-line timing slack monitoring methodology","authors":"Liangzhen Lai, V. Chandra, R. Aitken, Puneet Gupta","doi":"10.7873/DATE.2013.070","DOIUrl":"https://doi.org/10.7873/DATE.2013.070","url":null,"abstract":"In situ monitoring is an accurate way to monitor circuit delay or timing slack, but usually incurs significant overhead. We observe that most existing slack monitoring methods exclusively focus on monitoring path ending registers, which is not cost efficient from power and area perspectives.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81441949","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}
JPEG Encoding is a commonly performed application that is also very process and memory intensive, and not suited for low-power embedded systems with narrow data buses and small amounts of memory. An embedded system may also need to adapt its application in order to meet varying system constraints such as power, energy, time or bandwidth. We present here an extremely compact JPEG encoder that uses very few system resources, and which is capable of dynamically changing its Quality of Service (QoS) on the fly. The application was tested on a NIOS II core, AVR, and PIC24 microcontrollers with excellent results.
{"title":"An extremely compact JPEG encoder for adaptive embedded systems","authors":"Josef Schneider, S. Parameswaran","doi":"10.7873/DATE.2013.224","DOIUrl":"https://doi.org/10.7873/DATE.2013.224","url":null,"abstract":"JPEG Encoding is a commonly performed application that is also very process and memory intensive, and not suited for low-power embedded systems with narrow data buses and small amounts of memory. An embedded system may also need to adapt its application in order to meet varying system constraints such as power, energy, time or bandwidth. We present here an extremely compact JPEG encoder that uses very few system resources, and which is capable of dynamically changing its Quality of Service (QoS) on the fly. The application was tested on a NIOS II core, AVR, and PIC24 microcontrollers with excellent results.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81480517","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}
Model-based design using synchronous reactive (SR) models is widespread for the development of embedded control software. SR models ease verification and validation, and enable the automatic generation of implementations. In SR models, synchronous finite state machines (FSMs) are commonly used to capture changes of the system state under trigger events. The implementation of a synchronous FSM may be improved by using multiple software tasks instead of the traditional single-task solution. In this work, we propose methods to quantitatively analyze task implementations with respect to a breakdown factor that measures the timing robustness, and an action extensibility metric that measures the capability to accommodate upgrades. We propose an algorithm to generate a correct and efficient task implementation of synchronous FSMs for these two metrics, while guaranteeing the schedulability constraints.
{"title":"Robust and extensible task implementations of synchronous finite state machines","authors":"Qi Zhu, Peng Deng, M. Natale, Haibo Zeng","doi":"10.7873/DATE.2013.272","DOIUrl":"https://doi.org/10.7873/DATE.2013.272","url":null,"abstract":"Model-based design using synchronous reactive (SR) models is widespread for the development of embedded control software. SR models ease verification and validation, and enable the automatic generation of implementations. In SR models, synchronous finite state machines (FSMs) are commonly used to capture changes of the system state under trigger events. The implementation of a synchronous FSM may be improved by using multiple software tasks instead of the traditional single-task solution. In this work, we propose methods to quantitatively analyze task implementations with respect to a breakdown factor that measures the timing robustness, and an action extensibility metric that measures the capability to accommodate upgrades. We propose an algorithm to generate a correct and efficient task implementation of synchronous FSMs for these two metrics, while guaranteeing the schedulability constraints.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82450467","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}
Recently, source-level software models are increasingly used for software simulation in TLM (Transaction Level Modeling)-based virtual prototypes of multicore systems. A source-level model is generated by annotating timing information into application source code and allows for very fast software simulation. Accurate cache simulation is a key issue in multicore systems design because the memory subsystem accounts for a large portion of system performance. However, cache simulation at source level faces two major problems: (1) as target data addresses cannot be statically resolved during source code instrumentation, accurate data cache simulation is very difficult at source level, and (2) cache simulation brings large overhead in simulation performance and therefore cancels the gain of source level simulation. In this paper, we present a novel approach for accurate data cache simulation at source level. In addition, we also propose a cache modeling method to accelerate both instruction and data cache simulation. Our experiments show that simulation with the fast cache model achieves 450.7 MIPS (million simulated instructions per second) on a standard x86 laptop, 2.3x speedup compared with a standard cache model. The source-level models with cache simulation achieve accuracy comparable to an Instruction Set Simulator (ISS). We also use a complex multimedia application to demonstrate the efficiency of the proposed approach for multicore systems design.
{"title":"Fast and accurate cache modeling in source-level simulation of embedded software","authors":"Zhonglei Wang, J. Henkel","doi":"10.5555/2485288.2485432","DOIUrl":"https://doi.org/10.5555/2485288.2485432","url":null,"abstract":"Recently, source-level software models are increasingly used for software simulation in TLM (Transaction Level Modeling)-based virtual prototypes of multicore systems. A source-level model is generated by annotating timing information into application source code and allows for very fast software simulation. Accurate cache simulation is a key issue in multicore systems design because the memory subsystem accounts for a large portion of system performance. However, cache simulation at source level faces two major problems: (1) as target data addresses cannot be statically resolved during source code instrumentation, accurate data cache simulation is very difficult at source level, and (2) cache simulation brings large overhead in simulation performance and therefore cancels the gain of source level simulation. In this paper, we present a novel approach for accurate data cache simulation at source level. In addition, we also propose a cache modeling method to accelerate both instruction and data cache simulation. Our experiments show that simulation with the fast cache model achieves 450.7 MIPS (million simulated instructions per second) on a standard x86 laptop, 2.3x speedup compared with a standard cache model. The source-level models with cache simulation achieve accuracy comparable to an Instruction Set Simulator (ISS). We also use a complex multimedia application to demonstrate the efficiency of the proposed approach for multicore systems design.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83170491","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}
Many-core architectures used in embedded systems will contain hundreds of processors in the near future. Already now, it is necessary to study how to manage such systems when dynamically scheduling applications with different phases of parallelism and resource demands. A recent research area called invasive computing proposes a decentralized workload management scheme of such systems: applications may dynamically claim additional processors during execution and release these again, respectively. In this paper, we study how to apply the concepts of invasive computing for realizing decentralized core allocation schemes in homogeneous many-core systems with the goal of maximizing the average speedup of running applications at any point in time. A theoretical analysis based on game theory shows that it is possible to define a core allocation scheme that uses local information exchange between applications only, but is still able to provably converge to optimal results. The experimental evaluation demonstrates that this allocation scheme reduces the overhead in terms of exchanged messages by up to 61.4% and even the convergence time by up to 13.4% compared to an allocation scheme where all applications exchange information globally with each other.
{"title":"Game-theoretic analysis of decentralized core allocation schemes on many-core systems","authors":"S. Wildermann, Tobias Ziermann, J. Teich","doi":"10.5555/2485288.2485644","DOIUrl":"https://doi.org/10.5555/2485288.2485644","url":null,"abstract":"Many-core architectures used in embedded systems will contain hundreds of processors in the near future. Already now, it is necessary to study how to manage such systems when dynamically scheduling applications with different phases of parallelism and resource demands. A recent research area called invasive computing proposes a decentralized workload management scheme of such systems: applications may dynamically claim additional processors during execution and release these again, respectively. In this paper, we study how to apply the concepts of invasive computing for realizing decentralized core allocation schemes in homogeneous many-core systems with the goal of maximizing the average speedup of running applications at any point in time. A theoretical analysis based on game theory shows that it is possible to define a core allocation scheme that uses local information exchange between applications only, but is still able to provably converge to optimal results. The experimental evaluation demonstrates that this allocation scheme reduces the overhead in terms of exchanged messages by up to 61.4% and even the convergence time by up to 13.4% compared to an allocation scheme where all applications exchange information globally with each other.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89707355","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}
Sustainability of wireless sensor network (WSN) is crucial to its economy and efficiency. While previous works have focused on solving the energy source limitation through solar energy harvesting, we reveal in this paper that sensor node's lifespan could also be limited by memory wear-out and battery cycle life. We propose a sustainable sensor node design that takes all three limiting factors into consideration. Our design uses Phase Change Memory (PCM) to solve Flash memory's endurance issue. By leveraging PCM's adjustable write width, we propose a low-cost, fine-grained load tuning technique that allows the sensor node to match current MPP of solar panel and reduces the number of discharge/charge cycles on battery. Our modeling and experiments show that our sustainable sensor node design can achieve on average 5.1 years of node lifetime, more than 2× over the baseline.
{"title":"The design of sustainable wireless sensor network node using solar energy and Phase Change Memory","authors":"Ping Zhou, Youtao Zhang, Jun Yang","doi":"10.7873/DATE.2013.183","DOIUrl":"https://doi.org/10.7873/DATE.2013.183","url":null,"abstract":"Sustainability of wireless sensor network (WSN) is crucial to its economy and efficiency. While previous works have focused on solving the energy source limitation through solar energy harvesting, we reveal in this paper that sensor node's lifespan could also be limited by memory wear-out and battery cycle life. We propose a sustainable sensor node design that takes all three limiting factors into consideration. Our design uses Phase Change Memory (PCM) to solve Flash memory's endurance issue. By leveraging PCM's adjustable write width, we propose a low-cost, fine-grained load tuning technique that allows the sensor node to match current MPP of solar panel and reduces the number of discharge/charge cycles on battery. Our modeling and experiments show that our sustainable sensor node design can achieve on average 5.1 years of node lifetime, more than 2× over the baseline.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89316285","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}
Q. Xie, Siyu Yue, Massoud Pedram, Donghwa Shin, N. Chang
Cycle life of a battery largely varies according to the battery operating conditions, especially the battery temperature. In particular, batteries age much faster at high temperature. Extensive experiments have shown that the battery temperature varies dramatically during continuous charge or discharge process. This paper introduces a forced convection cooling technique for the batteries that power a portable system. Since the cooling fan is also powered by the same battery, it is critical to develop a highly effective, low power-consuming solution. In addition, there is a fundamental tradeoff between the service time of a battery equipped with fans and the cycle life of the same battery. In particular, as the fan speed is increased, the power dissipated by the fan goes up and hence the full charge capacity of the battery is lost at a faster rate, but at the same time, the battery temperature remains lower and hence the battery longevity increases. This is the first work that formulates the adaptive thermal management problem for batteries (ATMB) in portable systems and provides a systematic solution for it. A hierarchical algorithm combining reinforcement learning at the lower level and dynamic programming at the upper level is proposed to derive the ATMB policy.
{"title":"Adaptive thermal management for portable system batteries by forced convection cooling","authors":"Q. Xie, Siyu Yue, Massoud Pedram, Donghwa Shin, N. Chang","doi":"10.7873/DATE.2013.254","DOIUrl":"https://doi.org/10.7873/DATE.2013.254","url":null,"abstract":"Cycle life of a battery largely varies according to the battery operating conditions, especially the battery temperature. In particular, batteries age much faster at high temperature. Extensive experiments have shown that the battery temperature varies dramatically during continuous charge or discharge process. This paper introduces a forced convection cooling technique for the batteries that power a portable system. Since the cooling fan is also powered by the same battery, it is critical to develop a highly effective, low power-consuming solution. In addition, there is a fundamental tradeoff between the service time of a battery equipped with fans and the cycle life of the same battery. In particular, as the fan speed is increased, the power dissipated by the fan goes up and hence the full charge capacity of the battery is lost at a faster rate, but at the same time, the battery temperature remains lower and hence the battery longevity increases. This is the first work that formulates the adaptive thermal management problem for batteries (ATMB) in portable systems and provides a systematic solution for it. A hierarchical algorithm combining reinforcement learning at the lower level and dynamic programming at the upper level is proposed to derive the ATMB policy.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89829889","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}
Kai Hu, Bang-Ning Hsu, A. Madison, K. Chakrabarty, R. Fair
Advances in digital microfluidics and integrated sensing hold promise for a new generation of droplet-based biochips that can perform multiplexed assays to determine the identity of target molecules. Despite these benefits, defects and erroneous fluidic operations remain a major barrier to the adoption and deployment of these devices. We describe the first integrated demonstration of cyberphysical coupling in digital microfluidics, whereby errors in droplet transportation on the digital microfluidic platform are detected using capacitive sensors, the test outcome is interpreted by control hardware, and software-based error recovery is accomplished using dynamic reconfiguration. The hardware/software interface is realized through seamless interaction between control software, an off-the-shelf microcontroller and a frequency divider implemented on an FPGA. Experimental results are reported for a fabricated silicon device and links to videos are provided for the first-ever experimental demonstration of cyberphysical coupling and dynamic error recovery in digital microfluidic biochips.
{"title":"Fault detection, real-time error recovery, and experimental demonstration for digital microfluidic biochips","authors":"Kai Hu, Bang-Ning Hsu, A. Madison, K. Chakrabarty, R. Fair","doi":"10.7873/DATE.2013.124","DOIUrl":"https://doi.org/10.7873/DATE.2013.124","url":null,"abstract":"Advances in digital microfluidics and integrated sensing hold promise for a new generation of droplet-based biochips that can perform multiplexed assays to determine the identity of target molecules. Despite these benefits, defects and erroneous fluidic operations remain a major barrier to the adoption and deployment of these devices. We describe the first integrated demonstration of cyberphysical coupling in digital microfluidics, whereby errors in droplet transportation on the digital microfluidic platform are detected using capacitive sensors, the test outcome is interpreted by control hardware, and software-based error recovery is accomplished using dynamic reconfiguration. The hardware/software interface is realized through seamless interaction between control software, an off-the-shelf microcontroller and a frequency divider implemented on an FPGA. Experimental results are reported for a fabricated silicon device and links to videos are provided for the first-ever experimental demonstration of cyberphysical coupling and dynamic error recovery in digital microfluidic biochips.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83669897","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}
A. Belov, Huan Chen, A. Mishchenko, Joao Marques-Silva
Automatic abstraction is an important component of modern formal verification flows. A number of effective SAT-based automatic abstraction methods use unsatisfiable cores to guide the construction of abstractions. In this paper we analyze the impact of unsatisfiable core minimization, using state-of-the-art algorithms for the computation of minimally unsatisfiable subformulas (MUSes), on the effectiveness of a hybrid (counterexample-based and proof-based) abstraction engine. We demonstrate empirically that core minimization can lead to a significant reduction in the total verification time, particularly on difficult testcases. However, the resulting abstractions are not necessarily smaller. We notice that by varying the minimization effort the abstraction size can be controlled in a non-trivial manner. Based on this observation, we achieve a further reduction in the total verification time.
{"title":"Core minimization in SAT-based abstraction","authors":"A. Belov, Huan Chen, A. Mishchenko, Joao Marques-Silva","doi":"10.7873/DATE.2013.288","DOIUrl":"https://doi.org/10.7873/DATE.2013.288","url":null,"abstract":"Automatic abstraction is an important component of modern formal verification flows. A number of effective SAT-based automatic abstraction methods use unsatisfiable cores to guide the construction of abstractions. In this paper we analyze the impact of unsatisfiable core minimization, using state-of-the-art algorithms for the computation of minimally unsatisfiable subformulas (MUSes), on the effectiveness of a hybrid (counterexample-based and proof-based) abstraction engine. We demonstrate empirically that core minimization can lead to a significant reduction in the total verification time, particularly on difficult testcases. However, the resulting abstractions are not necessarily smaller. We notice that by varying the minimization effort the abstraction size can be controlled in a non-trivial manner. Based on this observation, we achieve a further reduction in the total verification time.","PeriodicalId":6310,"journal":{"name":"2013 Design, Automation & Test in Europe Conference & Exhibition (DATE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87805506","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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