Stefan Reif, Phillip Raffeck, Heiko Janker, Luis Gerhorst, T. Hönig, Wolfgang Schröder-Preikschat
As system complexity grows, embedded operating systems increasingly face the challenge to adhere to various non-functional constraints, such as response times and power limits. These requirements sometimes contradict and, often, no solution satisfies all constraints under all conditions. Changes in environmental conditions, application-level requirements, and user response time expectation hence demand for system-wide adaptions to resource management. We find that process synchronization constitutes a simple yet effective leverage point to balance between timing-related and energy-related constraints. This paper presents Earl, an implementation of reconfigurable locks in Linux that enables seamless transitions between high-performance and low-power operating modes.
{"title":"Earl","authors":"Stefan Reif, Phillip Raffeck, Heiko Janker, Luis Gerhorst, T. Hönig, Wolfgang Schröder-Preikschat","doi":"10.1145/3412821.3412825","DOIUrl":"https://doi.org/10.1145/3412821.3412825","url":null,"abstract":"As system complexity grows, embedded operating systems increasingly face the challenge to adhere to various non-functional constraints, such as response times and power limits. These requirements sometimes contradict and, often, no solution satisfies all constraints under all conditions. Changes in environmental conditions, application-level requirements, and user response time expectation hence demand for system-wide adaptions to resource management. We find that process synchronization constitutes a simple yet effective leverage point to balance between timing-related and energy-related constraints. This paper presents Earl, an implementation of reconfigurable locks in Linux that enables seamless transitions between high-performance and low-power operating modes.","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"40 1","pages":"24 - 29"},"PeriodicalIF":0.0,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88216900","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}
Luca Stornaiuolo, F. Carloni, Riccardo Pressiani, Giuseppe Natale, M. Santambrogio, D. Sciuto
In a quest for making FPGA technology more accessible to the software community, Xilinx recently released PYNQ, a framework for Zynq that relies on Python and overlays to ease the integration of functionalities of the programmable logic into applications. In this work we build upon this framework to enable transparent hardware acceleration for scientific computations for Zynq. We do so by providing a custom NumPy library designed for PYNQ, as it is the de-facto scientific library for Python. We then demonstrate the effectiveness of the proposed approach on a biomedical use case involving the extraction of features from the Electroencephalography (EEG).
{"title":"Enabling transparent hardware acceleration on Zynq SoC for scientific computing","authors":"Luca Stornaiuolo, F. Carloni, Riccardo Pressiani, Giuseppe Natale, M. Santambrogio, D. Sciuto","doi":"10.1145/3412821.3412826","DOIUrl":"https://doi.org/10.1145/3412821.3412826","url":null,"abstract":"In a quest for making FPGA technology more accessible to the software community, Xilinx recently released PYNQ, a framework for Zynq that relies on Python and overlays to ease the integration of functionalities of the programmable logic into applications. In this work we build upon this framework to enable transparent hardware acceleration for scientific computations for Zynq. We do so by providing a custom NumPy library designed for PYNQ, as it is the de-facto scientific library for Python. We then demonstrate the effectiveness of the proposed approach on a biomedical use case involving the extraction of features from the Electroencephalography (EEG).","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"17 1","pages":"30 - 35"},"PeriodicalIF":0.0,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1145/3412821.3412826","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46763028","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}
Chawki Benchehida, M. K. Benhaoua, H. Zahaf, G. Lipari
This paper presents Real-Time Network-on-chip-based architecture Analysis and Simulation tool (ReTiNAS), with a special focus on real-time communications. It allows fast and precise exploration of real-time design choices onto NoC architectures. ReTiNAS is an event-based simulator written in Python. It implements different real-time communication protocols and tracks the communications within the NoC at cycle level. Its modularity allows activating and deactivating different NoC components and easily extending the implemented protocols for more customized simulations and analysis. Further, we use ReTiNAS to perform a comparative study of analysis and simulation for different communication protocols using a wide set of synthetic experiments.
{"title":"An analysis and simulation tool of real-time communications in on-chip networks","authors":"Chawki Benchehida, M. K. Benhaoua, H. Zahaf, G. Lipari","doi":"10.1145/3412821.3412822","DOIUrl":"https://doi.org/10.1145/3412821.3412822","url":null,"abstract":"This paper presents Real-Time Network-on-chip-based architecture Analysis and Simulation tool (ReTiNAS), with a special focus on real-time communications. It allows fast and precise exploration of real-time design choices onto NoC architectures. ReTiNAS is an event-based simulator written in Python. It implements different real-time communication protocols and tracks the communications within the NoC at cycle level. Its modularity allows activating and deactivating different NoC components and easily extending the implemented protocols for more customized simulations and analysis. Further, we use ReTiNAS to perform a comparative study of analysis and simulation for different communication protocols using a wide set of synthetic experiments.","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"17 1","pages":"5 - 11"},"PeriodicalIF":0.0,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1145/3412821.3412822","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47132275","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 : 2020-01-06DOI: 10.1017/9781316662519.038
Harrison Kurunathan, Ricardo Severino, A. Koubâa, E. Tovar
Deterministic Synchronous Multichannel Extension (DSME) is a prominent MAC behavior first introduced in IEEE 802.15.4e. It can avail deterministic and best effort Service using its multisuperframe structure. RPL is a routing protocol for wireless networks with low power consumption and generally susceptible to packet loss. These two standards were designed independently but with the common objective to satisfy the requirements of IoT devices in terms of limited energy, reliability and determinism. A combination of these two protocols can integrate real-time QoS demanding and large-scale IoT networks. In this paper, we propose a new multi-channel, multi-timeslot scheduling algorithm called Symphony that provides QoS efficient schedules in DSME networks. In this paper we provide analytical and simulation based delay analysis for our approach against some state of the art algorithms. In this work, we show that integrating routing with DSME can improve reliability by 40% and by using Symphony, we can reduce the network delay by 10--20% against the state of the art algorithms.
{"title":"Symphony","authors":"Harrison Kurunathan, Ricardo Severino, A. Koubâa, E. Tovar","doi":"10.1017/9781316662519.038","DOIUrl":"https://doi.org/10.1017/9781316662519.038","url":null,"abstract":"\u0000 Deterministic Synchronous Multichannel Extension (DSME) is a prominent MAC behavior first introduced in IEEE 802.15.4e. It can avail deterministic and best effort Service using its multisuperframe structure. RPL is a routing protocol for wireless networks with low power consumption and generally susceptible to packet loss. These two standards were designed independently but with the common objective to satisfy the requirements of IoT devices in terms of limited energy, reliability and determinism. A combination of these two protocols can integrate\u0000 real-time QoS demanding\u0000 and\u0000 large-scale IoT networks.\u0000 In this paper, we propose a new multi-channel, multi-timeslot scheduling algorithm called Symphony that provides QoS efficient schedules in DSME networks. In this paper we provide analytical and simulation based delay analysis for our approach against some state of the art algorithms. In this work, we show that integrating routing with DSME can improve reliability by 40% and by using Symphony, we can reduce the network delay by 10--20% against the state of the art algorithms.\u0000","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1017/9781316662519.038","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47990275","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}
Harrison Kurunathan, Ricardo Severino, A. Koubâa, E. Tovar
Deterministic Synchronous Multichannel Extension (DSME) is a prominent MAC behavior first introduced in IEEE 802.15.4e supporting deterministic guarantees using its multisuperframe structure. DSME also facilitates techniques like multi-channel and Contention Access Period (CAP) reduction to increase the number of available guaranteed timeslots in a network. However, any tuning of these functionalities in dynamic scenarios is not explored in the standard. In this paper, we present a multisuperframe tuning technique called DynaMO which tunes the CAP reduction and Multisuperframe Order in an effective manner to improve flexibility and scalability, while guaranteeing bounded delay. We also provide simulations to prove that DynaMO with its dynamic tuning feature can offer up to 15--30% reduction in terms of latency in a large DSME network.
{"title":"DynaMO","authors":"Harrison Kurunathan, Ricardo Severino, A. Koubâa, E. Tovar","doi":"10.1145/3378408.3378409","DOIUrl":"https://doi.org/10.1145/3378408.3378409","url":null,"abstract":"Deterministic Synchronous Multichannel Extension (DSME) is a prominent MAC behavior first introduced in IEEE 802.15.4e supporting deterministic guarantees using its multisuperframe structure. DSME also facilitates techniques like multi-channel and Contention Access Period (CAP) reduction to increase the number of available guaranteed timeslots in a network. However, any tuning of these functionalities in dynamic scenarios is not explored in the standard. In this paper, we present a multisuperframe tuning technique called DynaMO which tunes the CAP reduction and Multisuperframe Order in an effective manner to improve flexibility and scalability, while guaranteeing bounded delay. We also provide simulations to prove that DynaMO with its dynamic tuning feature can offer up to 15--30% reduction in terms of latency in a large DSME network.","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"1998 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88244596","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}
Non-volatile memories, such as Phase Change Memories (PCM), have interesting energy properties. In effect, their static energy consumption is negligible while the consumed dynamic energy depends on the performed operation (read/write). Several Dynamic Voltage and Frequency Scaling (DVFS) mechanisms have been proposed to optimize the energy consumption of memory-bound tasks in embedded systems. In a hybrid memory, using both DRAM and PCM, these DVFS strategies need to be adapted to take into account the different energy behaviors of both memories. In this paper, we propose a Hybrid Memory-Aware DVFS strategy (HyMAD) to reduce the energy consumption for memory bound tasks. This mechanism relies on both the rate of PCM write operations and the overall memory access rate to tune the CPU frequency. HyMAD takes also into account the priority of a task to tune the "performance loss" / "energy efficiency" trade-off. We compared HyMAD with a state-of-the-art technique by evaluating the Energy-Squared-Delay product ( ED2P ). HyMAD ED2P enhancement was evaluated between 2--45% as compared to a system without DVFS and up to 20% as compared to a state-of-the-art DVFS strategy.
{"title":"HyMAD","authors":"Camélia Slimani, S. Rubini, Jalil Boukhobza","doi":"10.1145/3373400.3373407","DOIUrl":"https://doi.org/10.1145/3373400.3373407","url":null,"abstract":"\u0000 Non-volatile memories, such as Phase Change Memories (PCM), have interesting energy properties. In effect, their static energy consumption is negligible while the consumed dynamic energy depends on the performed operation (read/write). Several Dynamic Voltage and Frequency Scaling (DVFS) mechanisms have been proposed to optimize the energy consumption of memory-bound tasks in embedded systems. In a hybrid memory, using both DRAM and PCM, these DVFS strategies need to be adapted to take into account the different energy behaviors of both memories. In this paper, we propose a Hybrid Memory-Aware DVFS strategy (HyMAD) to reduce the energy consumption for memory bound tasks. This mechanism relies on both the rate of PCM write operations and the overall memory access rate to tune the CPU frequency. HyMAD takes also into account the priority of a task to tune the \"performance loss\" / \"energy efficiency\" trade-off. We compared HyMAD with a state-of-the-art technique by evaluating the Energy-Squared-Delay product (\u0000 ED2P\u0000 ). HyMAD\u0000 ED2P\u0000 enhancement was evaluated between 2--45% as compared to a system without DVFS and up to 20% as compared to a state-of-the-art DVFS strategy.\u0000","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1145/3373400.3373407","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42381331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Burns, Vincent Legout, A. Barbalace, B. Ravindran
We present PrVM, a framework for scheduling real-time VMs on multicore hardware. It addresses the intersection of the following problems: probabilistic real-time scheduling, VM scheduling, and full virtualization. Though each of these problems have been studied, their intersection - motivated by the need to consolidate multiple real-time software stacks, whose applications can be defined via probabilistic timing properties, onto a single embedded platform - is empty. PrVM uses a probabilistic model and timeliness optimality criterion. PrVM schedules VMs as server-like processes, computes time budgets using probabilistic methods, and aggregates task time budgets into VM time budgets. Experimental evaluations, using simulations and a concrete implementation, confirm the framework's effectiveness for synthetic benchmarks and multimedia applications.
{"title":"PrVM","authors":"K. Burns, Vincent Legout, A. Barbalace, B. Ravindran","doi":"10.1145/3373400.3373402","DOIUrl":"https://doi.org/10.1145/3373400.3373402","url":null,"abstract":"We present PrVM, a framework for scheduling real-time VMs on multicore hardware. It addresses the intersection of the following problems: probabilistic real-time scheduling, VM scheduling, and full virtualization. Though each of these problems have been studied, their intersection - motivated by the need to consolidate multiple real-time software stacks, whose applications can be defined via probabilistic timing properties, onto a single embedded platform - is empty. PrVM uses a probabilistic model and timeliness optimality criterion. PrVM schedules VMs as server-like processes, computes time budgets using probabilistic methods, and aggregates task time budgets into VM time budgets. Experimental evaluations, using simulations and a concrete implementation, confirm the framework's effectiveness for synthetic benchmarks and multimedia applications.","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78537685","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Preum, Sile Shu, Mustafa Hotaki, Ronald D. Williams, J. Stankovic, H. Alemzadeh
This paper presents our preliminary results on development of a Cognitive assistant system for Emergency Medical Services (CognitiveEMS) that aims to improve situational awareness and safety of first responders. CognitiveEMS integrates a suite of smart wearable sensors, devices, and analytics for real-time collection and analysis of in-situ data from incident scene and delivering dynamic data-driven insights to responders on the most effective response actions to take. We present the overall architecture of CognitiveEMS pipeline for processing information collected from the responder, which includes stages for converting speech to text, extracting medical and EMS protocol specific concepts, and modeling and execution of an EMS protocol. The performance of the pipeline is evaluated in both noise-free and noisy incident environments. The experiments are conducted using two types of publicly-available real EMS data: short radio calls and post-incident patient care reports. Three different noise profiles are considered for simulating the noisy environments: cafeteria, people talking, and emergency sirens. Noise was artificially added at 3 intensity levels of low, medium, and high to pre-recorded audio data. The results show that the i) state-of-the-art speech recognition tools such as Google Speech API are quite robust to low and medium noise intensities; ii) in the presence of high noise levels, the overall recall rate in medical concept annotation is reduced; and iii) the effect of noise often propagates to the final decision making stage and results in generating misleading feedback to responders.
{"title":"CognitiveEMS","authors":"S. Preum, Sile Shu, Mustafa Hotaki, Ronald D. Williams, J. Stankovic, H. Alemzadeh","doi":"10.1145/3357495.3357502","DOIUrl":"https://doi.org/10.1145/3357495.3357502","url":null,"abstract":"\u0000 This paper presents our preliminary results on development of a Cognitive assistant system for\u0000 Emergency Medical Services (CognitiveEMS)\u0000 that aims to improve situational awareness and safety of first responders.\u0000 CognitiveEMS\u0000 integrates a suite of smart wearable sensors, devices, and analytics for real-time collection and analysis of in-situ data from incident scene and delivering dynamic data-driven insights to responders on the most effective response actions to take. We present the overall architecture of\u0000 CognitiveEMS\u0000 pipeline for processing information collected from the responder, which includes stages for converting speech to text, extracting medical and EMS protocol specific concepts, and modeling and execution of an EMS protocol. The performance of the pipeline is evaluated in both noise-free and noisy incident environments. The experiments are conducted using two types of publicly-available real EMS data: short radio calls and post-incident patient care reports. Three different noise profiles are considered for simulating the noisy environments: cafeteria, people talking, and emergency sirens. Noise was artificially added at 3 intensity levels of low, medium, and high to pre-recorded audio data. The results show that the i) state-of-the-art speech recognition tools such as Google Speech API are quite robust to low and medium noise intensities; ii) in the presence of high noise levels, the overall recall rate in medical concept annotation is reduced; and iii) the effect of noise often propagates to the final decision making stage and results in generating misleading feedback to responders.\u0000","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86832810","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}
Hung Nguyen, Radoslav Ivanov, Sara B. DeMauro, James Weimer
Remote physiological monitoring is increasing in popularity with the evolution of technologies in the healthcare industry. However, the current solutions for remote monitoring of blood-oxygen saturation, one of the most common continuously monitored vital signs, either have inconsistent accuracy or are not secure for transmitting over the network. In this paper, we propose RePulmo, an open-source platform for secure and accurate remote pulmonary data monitoring. RePulmo satisfies both robustness and security requirements by utilizing hospital-grade pulse oximeter devices with multiple layers of security enforcement. We describe two applications of RePulmo, namely (1) a remote pulmonary monitoring system for infants to support the Children's Hospital of Philadelphia (CHOP) clinical trial; (2) a proof-of-concept of a low SpO2 smart alarm system.
{"title":"RePulmo","authors":"Hung Nguyen, Radoslav Ivanov, Sara B. DeMauro, James Weimer","doi":"10.1145/3357495.3357501","DOIUrl":"https://doi.org/10.1145/3357495.3357501","url":null,"abstract":"Remote physiological monitoring is increasing in popularity with the evolution of technologies in the healthcare industry. However, the current solutions for remote monitoring of blood-oxygen saturation, one of the most common continuously monitored vital signs, either have inconsistent accuracy or are not secure for transmitting over the network. In this paper, we propose RePulmo, an open-source platform for secure and accurate remote pulmonary data monitoring. RePulmo satisfies both robustness and security requirements by utilizing hospital-grade pulse oximeter devices with multiple layers of security enforcement. We describe two applications of RePulmo, namely (1) a remote pulmonary monitoring system for infants to support the Children's Hospital of Philadelphia (CHOP) clinical trial; (2) a proof-of-concept of a low SpO2 smart alarm system.","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88869396","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}
For the Internet of Things (IoT) applications that send a few bytes of sensor information infrequently, several long-range IoT technologies have been conceived. Narrowband IoT (NB-IoT) is one of th...
{"title":"Opportunities and challenges in using energy-harvesting for NB-IoT","authors":"HaridasA., S. RaoV., R. V. Prasad, SarkarC.","doi":"10.1145/3292384.3292386","DOIUrl":"https://doi.org/10.1145/3292384.3292386","url":null,"abstract":"For the Internet of Things (IoT) applications that send a few bytes of sensor information infrequently, several long-range IoT technologies have been conceived. Narrowband IoT (NB-IoT) is one of th...","PeriodicalId":37024,"journal":{"name":"ACM SIGBED Review","volume":"15 1","pages":"7-13"},"PeriodicalIF":0.0,"publicationDate":"2018-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1145/3292384.3292386","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44460862","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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