Haitao Zhao, Xiaoying Lv, Guiyang Li, Zhigong Wang
The design of the RF transmitter for transcutaneous energy transmission is analyzed and experimentally tested. The transmitter consists of a crystal oscillator, a class-E power amplifier, a supply voltage regulator, and a transmitting coil. The transmitting coils made of enameled wire and the receiving coils made on Printed Circuit Board (PCB) were designed simultaneously. In this paper, the compensated methods of transmitting coils and receiving coils are discussed. The topology and working principle of the transmitter are analyzed, the design parameters of the transmitter are calculated. Driven by a crystal oscillator, the class-E power amplifier operates at 13.56 MHz (ISM frequency band). In the conditions of a distance of 10 mm between two coils and 5-9 V DC supply, the voltage measured across the transmitting coil is from 90 V to 130 V, while the voltage across the receiving coil can reach 28 V. The experimental results are in good agreement with the simulating ones. With a distance of 35 mm and a slice of skin between the coils, the receiving voltage reaches still up to 4 V at least, which meets the need of implanted integrated circuits.
{"title":"Design and Experiments of Transmitter for Transcutaneous Energy Transmission","authors":"Haitao Zhao, Xiaoying Lv, Guiyang Li, Zhigong Wang","doi":"10.1109/BSN.2009.27","DOIUrl":"https://doi.org/10.1109/BSN.2009.27","url":null,"abstract":"The design of the RF transmitter for transcutaneous energy transmission is analyzed and experimentally tested. The transmitter consists of a crystal oscillator, a class-E power amplifier, a supply voltage regulator, and a transmitting coil. The transmitting coils made of enameled wire and the receiving coils made on Printed Circuit Board (PCB) were designed simultaneously. In this paper, the compensated methods of transmitting coils and receiving coils are discussed. The topology and working principle of the transmitter are analyzed, the design parameters of the transmitter are calculated. Driven by a crystal oscillator, the class-E power amplifier operates at 13.56 MHz (ISM frequency band). In the conditions of a distance of 10 mm between two coils and 5-9 V DC supply, the voltage measured across the transmitting coil is from 90 V to 130 V, while the voltage across the receiving coil can reach 28 V. The experimental results are in good agreement with the simulating ones. With a distance of 35 mm and a slice of skin between the coils, the receiving voltage reaches still up to 4 V at least, which meets the need of implanted integrated circuits.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127097680","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}
Wireless sensor-based Body Area Networks (BAN) can play a major role in providing individualized health-care. Given their limited power sources, sensors in BAN have to be energy-efficient to ensure longevity and safety of the network. Recent years have seen the emergence of a new class of security solutions for BANs, called cyber-physical security solutions, which enable plug-n-play secure communication within a BAN using environment derived features. However, due to this environment-coupled nature, they require signal processing and mathematical routines which can be potentially very energy-intensive for individual sensors. In this paper, we characterize the "energy footprint" of a cyber-physical security solution, the Physiological signal based Key Agreement (PKA). The goal is to - 1) compute PKA's energy consumption, and 2) determine whether prominent energy scavenging techniques can be used to meet its requirements. Our results show that the energy requirements of PKA is small and is sustainable by many of the prominent energy scavenging techniques, such as body heat and ambulation, making it a "green" solution for large scale deployments.
{"title":"Green and Sustainable Cyber-Physical Security Solutions for Body Area Networks","authors":"K. Venkatasubramanian, Ayan Banerjee, S. Gupta","doi":"10.1109/BSN.2009.47","DOIUrl":"https://doi.org/10.1109/BSN.2009.47","url":null,"abstract":"Wireless sensor-based Body Area Networks (BAN) can play a major role in providing individualized health-care. Given their limited power sources, sensors in BAN have to be energy-efficient to ensure longevity and safety of the network. Recent years have seen the emergence of a new class of security solutions for BANs, called cyber-physical security solutions, which enable plug-n-play secure communication within a BAN using environment derived features. However, due to this environment-coupled nature, they require signal processing and mathematical routines which can be potentially very energy-intensive for individual sensors. In this paper, we characterize the \"energy footprint\" of a cyber-physical security solution, the Physiological signal based Key Agreement (PKA). The goal is to - 1) compute PKA's energy consumption, and 2) determine whether prominent energy scavenging techniques can be used to meet its requirements. Our results show that the energy requirements of PKA is small and is sustainable by many of the prominent energy scavenging techniques, such as body heat and ambulation, making it a \"green\" solution for large scale deployments.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126194921","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}
Yan Zhao, A. Sani, Y. Hao, Su-Lin Lee, Guang-Zhong Yang
This paper presents a simulation environment, based on the parallel finite-difference time-domain (FDTD) method, for subject-specific radio channel modeling in wireless body sensor networks (WBSNs). The simulation environment takes into account realistic antenna radiation patterns in channel modeling to analyze their effects on WBSNs. The proposed simulation tool is applied to a study of body communication channels in a hospital environment and the results are validated by site measurement. It is found from our study that radio channel characteristics in WBSNs are subject specific and associated with human genders and body mass indices (BMIs).
{"title":"A Simulation Environment for Subject-Specific Radio Channel Modeling in Wireless Body Sensor Networks","authors":"Yan Zhao, A. Sani, Y. Hao, Su-Lin Lee, Guang-Zhong Yang","doi":"10.1109/BSN.2009.64","DOIUrl":"https://doi.org/10.1109/BSN.2009.64","url":null,"abstract":"This paper presents a simulation environment, based on the parallel finite-difference time-domain (FDTD) method, for subject-specific radio channel modeling in wireless body sensor networks (WBSNs). The simulation environment takes into account realistic antenna radiation patterns in channel modeling to analyze their effects on WBSNs. The proposed simulation tool is applied to a study of body communication channels in a hospital environment and the results are validated by site measurement. It is found from our study that radio channel characteristics in WBSNs are subject specific and associated with human genders and body mass indices (BMIs).","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116848583","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}
In this paper we present the technical requirements and system issues for wireless Medical Body Sensor Networks (BSNs). Design guidelines are driven by the need to improve ambulatory patient monitoring and care while reducing logistic constraints for patients as well as healthcare professionals. We present our study on three key components of Medical BSN: On-body wireless link (to characterize the RF channel for body worn wireless devices), Coupling between bodies (to characterize the RF interaction between bodies) and Coexistence of Medical BSNs in the RF spectrum. Results and conclusions are presented through simulation and measurement studies. We also discuss our FCC petition for spectrum allocation.
{"title":"Wireless Propagation and Coexistence of Medical Body Sensor Networks for Ambulatory Patient Monitoring","authors":"David M. Davenport, Budhaditya Deb, F. Ross","doi":"10.1109/BSN.2009.8","DOIUrl":"https://doi.org/10.1109/BSN.2009.8","url":null,"abstract":"In this paper we present the technical requirements and system issues for wireless Medical Body Sensor Networks (BSNs). Design guidelines are driven by the need to improve ambulatory patient monitoring and care while reducing logistic constraints for patients as well as healthcare professionals. We present our study on three key components of Medical BSN: On-body wireless link (to characterize the RF channel for body worn wireless devices), Coupling between bodies (to characterize the RF interaction between bodies) and Coexistence of Medical BSNs in the RF spectrum. Results and conclusions are presented through simulation and measurement studies. We also discuss our FCC petition for spectrum allocation.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114743158","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}
R. Ali, L. Atallah, Benny P. L. Lo, Guang-Zhong Yang
Activity monitoring is an important part of pervasive sensing, particularly for assessing activities of daily living for elderly patients and those with chronic diseases. Previous studies have mainly focused on binary transitions between activities, but have overlooked detailed transitional patterns. For patient studies, this transition period can be prolonged and may be indicative of the progression of disease. To observe, as well as quantify, transitional activities, a manifold embedding approach is proposed in this paper. The method uses a spectral graph partitioning and transition labelling approach for identifying principal and transitional activity patterns. The practical value of the work is demonstrated through laboratory experiments for identifying specific transitions and detecting simulated motion impairment.
{"title":"Transitional Activity Recognition with Manifold Embedding","authors":"R. Ali, L. Atallah, Benny P. L. Lo, Guang-Zhong Yang","doi":"10.1109/BSN.2009.42","DOIUrl":"https://doi.org/10.1109/BSN.2009.42","url":null,"abstract":"Activity monitoring is an important part of pervasive sensing, particularly for assessing activities of daily living for elderly patients and those with chronic diseases. Previous studies have mainly focused on binary transitions between activities, but have overlooked detailed transitional patterns. For patient studies, this transition period can be prolonged and may be indicative of the progression of disease. To observe, as well as quantify, transitional activities, a manifold embedding approach is proposed in this paper. The method uses a spectral graph partitioning and transition labelling approach for identifying principal and transitional activity patterns. The practical value of the work is demonstrated through laboratory experiments for identifying specific transitions and detecting simulated motion impairment.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114678115","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}
Brendan O'Huiginn, B. Smyth, G. Coughlan, D. Fitzgerald, B. Caulfield
Exercise therapy is prescribed by physiotherapists and rehabilitation practitioners as part of the treatment programme for many movement impairment disorders. Poor adherence and inadequate exercise technique often result in poor outcomes for these patients and delays their return to full physical function. Therapeutic exergaming, which is the use of computer games and body-worn motion tracking sensors to teach therapeutic exercise programmes to patients, may offer solutions to these problems. In this paper we describe one such system, known as FlyFit, which offers a sensor-driven flight game environment that allows physiotherapists to intuitively design game levels that will induce patients to correctly carry out their exercises programme. A 4-week pilot study to investigate the training effect of the system compared to a conventional exercise training approach is described. Results suggest these exergaming systems may induce improvements in balance and strength similar to the conventional programme along with increased levels of intrinsic motivation but further research is warranted.
{"title":"Therapeutic Exergaming","authors":"Brendan O'Huiginn, B. Smyth, G. Coughlan, D. Fitzgerald, B. Caulfield","doi":"10.1109/BSN.2009.43","DOIUrl":"https://doi.org/10.1109/BSN.2009.43","url":null,"abstract":"Exercise therapy is prescribed by physiotherapists and rehabilitation practitioners as part of the treatment programme for many movement impairment disorders. Poor adherence and inadequate exercise technique often result in poor outcomes for these patients and delays their return to full physical function. Therapeutic exergaming, which is the use of computer games and body-worn motion tracking sensors to teach therapeutic exercise programmes to patients, may offer solutions to these problems. In this paper we describe one such system, known as FlyFit, which offers a sensor-driven flight game environment that allows physiotherapists to intuitively design game levels that will induce patients to correctly carry out their exercises programme. A 4-week pilot study to investigate the training effect of the system compared to a conventional exercise training approach is described. Results suggest these exergaming systems may induce improvements in balance and strength similar to the conventional programme along with increased levels of intrinsic motivation but further research is warranted.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129843221","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}
P. Kuryloski, A. Giani, Roberta Giannantonio, K. Gilani, Raffaele Gravina, Ville-Pekka Seppä, E. Seto, Victor Shia, Curtis Wang, Posu Yan, A. Yang, J. Hyttinen, S. Sastry, S. Wicker, R. Bajcsy
We present an open-source platform for wireless body sensor networks called DexterNet. The system supports real-time, persistent human monitoring in both indoor and outdoor environments. The platform utilizes a three-layer architecture to control heterogeneous body sensors. The first layer called the body sensor layer (BSL) deals with design of heterogeneous body sensors and their instrumentation on the body. At the second layer called the personal network layer (PNL), the body sensors on a single subject communicate with a mobile base station, which supports Linux OS and the IEEE 802.15.4 protocol. The BSL and PNL functions are abstracted and implemented as an open-source software library, called Signal Processing In Node Environment (SPINE). A DexterNet network is scalable, and can be reconfigured on-the-fly via SPINE. At the third layer called the global network layer (GNL), multiple PNLs communicate with a remote Internet server to permanently log the sensor data and support higher-level applications. We demonstrate the versatility of the DexterNet platform via several real-world applications.
{"title":"DexterNet: An Open Platform for Heterogeneous Body Sensor Networks and its Applications","authors":"P. Kuryloski, A. Giani, Roberta Giannantonio, K. Gilani, Raffaele Gravina, Ville-Pekka Seppä, E. Seto, Victor Shia, Curtis Wang, Posu Yan, A. Yang, J. Hyttinen, S. Sastry, S. Wicker, R. Bajcsy","doi":"10.1109/BSN.2009.31","DOIUrl":"https://doi.org/10.1109/BSN.2009.31","url":null,"abstract":"We present an open-source platform for wireless body sensor networks called DexterNet. The system supports real-time, persistent human monitoring in both indoor and outdoor environments. The platform utilizes a three-layer architecture to control heterogeneous body sensors. The first layer called the body sensor layer (BSL) deals with design of heterogeneous body sensors and their instrumentation on the body. At the second layer called the personal network layer (PNL), the body sensors on a single subject communicate with a mobile base station, which supports Linux OS and the IEEE 802.15.4 protocol. The BSL and PNL functions are abstracted and implemented as an open-source software library, called Signal Processing In Node Environment (SPINE). A DexterNet network is scalable, and can be reconfigured on-the-fly via SPINE. At the third layer called the global network layer (GNL), multiple PNLs communicate with a remote Internet server to permanently log the sensor data and support higher-level applications. We demonstrate the versatility of the DexterNet platform via several real-world applications.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126414464","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}
There is a need for wearable sensors to assess physiological signals and body kinematics during exercise. Such sensors need to be straightforward to use, and ideally the complete system integrated fully within a garment. This would allow wearers to monitor their progress as they undergo an exercise training programme without the need to attach external devices. This takes physiological monitoring into a more natural setting. By developing textile sensors the intelligence is integrated into a sports garment in an innocuous manner. A number of textile based sensors are presented here that have been integrated into garments for various sports applications.
{"title":"Textile-Based Wearable Sensors for Assisting Sports Performance","authors":"S. Coyle, D. Morris, K. Lau, D. Diamond, N. Moyna","doi":"10.1109/BSN.2009.57","DOIUrl":"https://doi.org/10.1109/BSN.2009.57","url":null,"abstract":"There is a need for wearable sensors to assess physiological signals and body kinematics during exercise. Such sensors need to be straightforward to use, and ideally the complete system integrated fully within a garment. This would allow wearers to monitor their progress as they undergo an exercise training programme without the need to attach external devices. This takes physiological monitoring into a more natural setting. By developing textile sensors the intelligence is integrated into a sports garment in an innocuous manner. A number of textile based sensors are presented here that have been integrated into garments for various sports applications.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121472080","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}
This article describes an approach to detecting mental stress using unobtrusive wearable sensors. The approach relies on estimating the state of the autonomic nervous system from an analysis of heart rate variability. Namely, we use a non-linear system identification technique known as principal dynamic modes (PDM) to predict the activation level of the two autonomic branches: sympathetic (i.e. stress-inducing) and parasympathetic (i.e. relaxation-related). We validate the method on a discrimination problem with two psychophysiological conditions, one associated with mental tasks and one induced by relaxation exercises. Our results indicate that PDM features are more stable and less subject-dependent than spectral features, though the latter provide higher classification performance within subjects. When PDM and spectral features are combined, our system discriminates stressful events with a success rate of 83% within subjects (69% between subjects).
{"title":"Using Heart Rate Monitors to Detect Mental Stress","authors":"Jongyoon Choi, R. Gutierrez-Osuna","doi":"10.1109/BSN.2009.13","DOIUrl":"https://doi.org/10.1109/BSN.2009.13","url":null,"abstract":"This article describes an approach to detecting mental stress using unobtrusive wearable sensors. The approach relies on estimating the state of the autonomic nervous system from an analysis of heart rate variability. Namely, we use a non-linear system identification technique known as principal dynamic modes (PDM) to predict the activation level of the two autonomic branches: sympathetic (i.e. stress-inducing) and parasympathetic (i.e. relaxation-related). We validate the method on a discrimination problem with two psychophysiological conditions, one associated with mental tasks and one induced by relaxation exercises. Our results indicate that PDM features are more stable and less subject-dependent than spectral features, though the latter provide higher classification performance within subjects. When PDM and spectral features are combined, our system discriminates stressful events with a success rate of 83% within subjects (69% between subjects).","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126616845","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}
By the innovative application of body worn Wireless Sensor Networks (WSNs) patients could avoid or reduce hospital stays while still being in constant contact with their healthcare providers. However, while wireless technology is far advanced it has yet to be accepted by the medical sector, primarily through concerns of cost, reliability and interoperability. Bluetooth low energy meets all of these requirements and has the added advantage that it will be able to communicate with the Bluetooth chips likely to be fitted to the next generation of mobile phones. That means patient data could be transmitted to a medical facility via the cellular network eliminating the need to build expensive specialised communication links. But while Bluetooth low energy specification promises much, there are some technical challenges – such as protection of privacy - to overcome.
{"title":"Reducing Healthcare Costs with Wireless Technology","authors":"Alf Helge Omre","doi":"10.1109/BSN.2009.68","DOIUrl":"https://doi.org/10.1109/BSN.2009.68","url":null,"abstract":"By the innovative application of body worn Wireless Sensor Networks (WSNs) patients could avoid or reduce hospital stays while still being in constant contact with their healthcare providers. However, while wireless technology is far advanced it has yet to be accepted by the medical sector, primarily through concerns of cost, reliability and interoperability. Bluetooth low energy meets all of these requirements and has the added advantage that it will be able to communicate with the Bluetooth chips likely to be fitted to the next generation of mobile phones. That means patient data could be transmitted to a medical facility via the cellular network eliminating the need to build expensive specialised communication links. But while Bluetooth low energy specification promises much, there are some technical challenges – such as protection of privacy - to overcome.","PeriodicalId":269861,"journal":{"name":"2009 Sixth International Workshop on Wearable and Implantable Body Sensor Networks","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126992733","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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