Pub Date : 2011-03-07DOI: 10.1109/WISNET.2011.5725035
Hisanori Matsumoto, Haruka Kusano, Tatsushi Morokuma, K. Sakamura
This paper describes a TDOA-based positioning system by means of ultra-wideband impulse radio (UWB-IR). The system consists of three reference nodes and a location server. One of the reference nodes transmits an impulse signal to other reference nodes for synchronizing them immediately after receiving an impulse signal sent from a target node. Thus, no additional component for the synchronization is needed in our system. The positioning accuracy was investigated by a simulation and an experiment. The experiment was performed with our UWB-IR transceivers and the results demonstrated that 67% of the position estimates correctly predicted the true positions within 0.36 m.
{"title":"Numerical and experimental investigation of TDOA-based positioning system by ultra-wideband impulse radio","authors":"Hisanori Matsumoto, Haruka Kusano, Tatsushi Morokuma, K. Sakamura","doi":"10.1109/WISNET.2011.5725035","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725035","url":null,"abstract":"This paper describes a TDOA-based positioning system by means of ultra-wideband impulse radio (UWB-IR). The system consists of three reference nodes and a location server. One of the reference nodes transmits an impulse signal to other reference nodes for synchronizing them immediately after receiving an impulse signal sent from a target node. Thus, no additional component for the synchronization is needed in our system. The positioning accuracy was investigated by a simulation and an experiment. The experiment was performed with our UWB-IR transceivers and the results demonstrated that 67% of the position estimates correctly predicted the true positions within 0.36 m.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116325889","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725021
M. Pereira da Cunha, R. Lad, P. Davulis, A. Canabal, T. Moonlight, S. Moulzolf, D. Frankel, T. Pollard, D. McCann, E. Dudzik, A. Abedi, D. Hummels, G. Bernhardt
This paper reviews current progress in the area of wireless microwave acoustic sensor technology, and discusses advances in wireless interrogation systems that can operate in harsh environments. The use of wireless, battery-free, low maintenance surface acoustic wave (SAW) sensors has been successfully demonstrated in applications including high temperature turbine engines and inflatable aerospace structures. Wireless interrogation of multiple sensors up to 910°C has been established and sensor tests in gas turbine engine are reported. This paper elaborates on several aspects of the technology, including: high-temperature thin-film electrode and sensor development, temperature cycling, thermal-shock behavior, testing in turbine engine environments, sensor packaging and attachment, wireless operation, and adaptation to energy and industrial applications.
{"title":"Wireless acoustic wave sensors and systems for harsh environment applications","authors":"M. Pereira da Cunha, R. Lad, P. Davulis, A. Canabal, T. Moonlight, S. Moulzolf, D. Frankel, T. Pollard, D. McCann, E. Dudzik, A. Abedi, D. Hummels, G. Bernhardt","doi":"10.1109/WISNET.2011.5725021","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725021","url":null,"abstract":"This paper reviews current progress in the area of wireless microwave acoustic sensor technology, and discusses advances in wireless interrogation systems that can operate in harsh environments. The use of wireless, battery-free, low maintenance surface acoustic wave (SAW) sensors has been successfully demonstrated in applications including high temperature turbine engines and inflatable aerospace structures. Wireless interrogation of multiple sensors up to 910°C has been established and sensor tests in gas turbine engine are reported. This paper elaborates on several aspects of the technology, including: high-temperature thin-film electrode and sensor development, temperature cycling, thermal-shock behavior, testing in turbine engine environments, sensor packaging and attachment, wireless operation, and adaptation to energy and industrial applications.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"40 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132497579","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725033
S. Narieda
This paper presents a probabilistic transmission control technique for the distributed estimation in WSNs. The presented technique is based on a novel transmission control which is to minimize a mean squared error of estimation by increasing the packet transmission success probability of only sensors having the high observation SNR. In the presented method, the transmission of sensors is probabilistically decided whether the SNR of sensor is greater than the threshold whereas the transmission of sensors is deterministically decided in the conventional method. To achieve the presented method, we introduce a probabilistic transmission control function that gives each sensor a probabilistic value (from 0 to 1) as the transmission probability. Also, since the presented method can allows sensors to retransmit messages, it can be expected that the reliability of estimate increases. We employed the collision channel model where the transmission from the sensor to the FC is successful only when no other sensors are transmitting in the same time slot. Also, we assume that each sensor observe unknown at the beginning of the limited observation period, and each sensor can transmits observation only the limited retransmission time. Based on the model, theoretical packet transmission success probability of the presented and conventional method is derived. Numerical results are presented to valid the effectiveness of the presented method.
{"title":"Performance analysis of probabilistic transmission control for distributed estimation in wireless sensor networks","authors":"S. Narieda","doi":"10.1109/WISNET.2011.5725033","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725033","url":null,"abstract":"This paper presents a probabilistic transmission control technique for the distributed estimation in WSNs. The presented technique is based on a novel transmission control which is to minimize a mean squared error of estimation by increasing the packet transmission success probability of only sensors having the high observation SNR. In the presented method, the transmission of sensors is probabilistically decided whether the SNR of sensor is greater than the threshold whereas the transmission of sensors is deterministically decided in the conventional method. To achieve the presented method, we introduce a probabilistic transmission control function that gives each sensor a probabilistic value (from 0 to 1) as the transmission probability. Also, since the presented method can allows sensors to retransmit messages, it can be expected that the reliability of estimate increases. We employed the collision channel model where the transmission from the sensor to the FC is successful only when no other sensors are transmitting in the same time slot. Also, we assume that each sensor observe unknown at the beginning of the limited observation period, and each sensor can transmits observation only the limited retransmission time. Based on the model, theoretical packet transmission success probability of the presented and conventional method is derived. Numerical results are presented to valid the effectiveness of the presented method.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121221602","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725034
L. Cisoni, D. Trinchero
Recently, novel wireless sensor network architectures, suitable to monitor fluids characteristics from inside a conduit, have been proposed in the literature. These techniques require the implementation of a sensor equipped with an electromagnetic front-end able to transmit through a dissipative medium. This requires antennas with high transmission efficiency, even if inserted in liquids, in confined spaces, hence with high attention to the reduction of the dimensions. The present paper introduces an efficient design procedure that allows an easy and fast definition of the microwave circuit. The procedure is particularly suitable when the antenna is inserted in a complex scenario, with several media in the near field of the radiator.
{"title":"An efficient technique for the design of miniaturized wireless sensors within liquids","authors":"L. Cisoni, D. Trinchero","doi":"10.1109/WISNET.2011.5725034","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725034","url":null,"abstract":"Recently, novel wireless sensor network architectures, suitable to monitor fluids characteristics from inside a conduit, have been proposed in the literature. These techniques require the implementation of a sensor equipped with an electromagnetic front-end able to transmit through a dissipative medium. This requires antennas with high transmission efficiency, even if inserted in liquids, in confined spaces, hence with high attention to the reduction of the dimensions. The present paper introduces an efficient design procedure that allows an easy and fast definition of the microwave circuit. The procedure is particularly suitable when the antenna is inserted in a complex scenario, with several media in the near field of the radiator.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134561183","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725020
S. Zorn, Matthias Maser, Alexander Goetz, R. Rose, R. Weigel
Recent statistics show an increase in environmental disasters, a fact which is also perceivable to the public as reports of avalanches, earthquakes and landslides mount in media coverage. Search and Rescue with modern localization techniques consequently attracts attention from scientific and industrial sides. This paper introduces one part of the I-LOV project, endorsed by the German Federal Ministry of Education and Research. In this project partners from relief organizations, universities and industry investigate enhancements to disaster handling and victim rescue. One possible option is to take advantage of the fact, that a lot of people own a mobile phone today. To locate a person by his or her mobile phone requires to take over the phone by an own Base Transceiver Station (BTS). Jamming all other networks is one option to achieve that. This paper will introduce a new Field Programmable Gate Array (FPGA) based jamming system which consumes little power and disturbs only small parts of the GSM spectrum but reliably cuts all connections between mobile stations (MS) and existing BTS.
{"title":"A power saving jamming system for E-GSM900 and DCS1800 cellular phone networks for search and rescue applications","authors":"S. Zorn, Matthias Maser, Alexander Goetz, R. Rose, R. Weigel","doi":"10.1109/WISNET.2011.5725020","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725020","url":null,"abstract":"Recent statistics show an increase in environmental disasters, a fact which is also perceivable to the public as reports of avalanches, earthquakes and landslides mount in media coverage. Search and Rescue with modern localization techniques consequently attracts attention from scientific and industrial sides. This paper introduces one part of the I-LOV project, endorsed by the German Federal Ministry of Education and Research. In this project partners from relief organizations, universities and industry investigate enhancements to disaster handling and victim rescue. One possible option is to take advantage of the fact, that a lot of people own a mobile phone today. To locate a person by his or her mobile phone requires to take over the phone by an own Base Transceiver Station (BTS). Jamming all other networks is one option to achieve that. This paper will introduce a new Field Programmable Gate Array (FPGA) based jamming system which consumes little power and disturbs only small parts of the GSM spectrum but reliably cuts all connections between mobile stations (MS) and existing BTS.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114904876","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725032
Y. Takizawa
The localization of sensor node is one of the key issues for sensor network systems. Therefore, several localization systems to obtain precise location information have been researched. However, they need completely configured space using a large number of anchor nodes of which location are well known, and are not suitable for sensor networks. To avoid the problems, we proposed the node localization method based on Self-Organizing Maps and needs no prepared space with a large number of anchor nodes. But, as in other similar precise localization methods, the proposed method needs advanced distance measurements unavailable in conventional sensor node systems. In this paper, the modification of the self-organizing localization for distance measurement that uses received signal strength available in conventional sensor node systems is described and its location estimation accuracy is shown.
{"title":"Node localization for sensor networks using Self-Organizing Maps","authors":"Y. Takizawa","doi":"10.1109/WISNET.2011.5725032","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725032","url":null,"abstract":"The localization of sensor node is one of the key issues for sensor network systems. Therefore, several localization systems to obtain precise location information have been researched. However, they need completely configured space using a large number of anchor nodes of which location are well known, and are not suitable for sensor networks. To avoid the problems, we proposed the node localization method based on Self-Organizing Maps and needs no prepared space with a large number of anchor nodes. But, as in other similar precise localization methods, the proposed method needs advanced distance measurements unavailable in conventional sensor node systems. In this paper, the modification of the self-organizing localization for distance measurement that uses received signal strength available in conventional sensor node systems is described and its location estimation accuracy is shown.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129259462","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725026
M. Scardelletti, G. Ponchak
Oscillators that operate at 720 and 940 MHz and characterized over a temperature range of 25 °C to 200 °C and 250 °C, respectively, are presented. The oscillators are designed on alumina substrates with typical integrated circuit fabrication techniques. Cree SiC MESFETs, thin film metal-insulator-metal capacitors and spiral inductors, and Johanson miniature chip antennas make-up the circuits. The output power and phase noise are presented as a function of temperature and frequency.
振荡器工作在720和940 MHz，特征温度范围为25°C至200°C和250°C，分别提出。该振荡器采用典型集成电路制造技术设计在氧化铝衬底上。Cree SiC mesfet，薄膜金属-绝缘体-金属电容器和螺旋电感器，以及约翰逊微型芯片天线组成了电路。输出功率和相位噪声是温度和频率的函数。
{"title":"Characterization of 720 and 940 MHz oscillators with chip antenna for wireless sensors from room temperature to 200 and 250 °C","authors":"M. Scardelletti, G. Ponchak","doi":"10.1109/WISNET.2011.5725026","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725026","url":null,"abstract":"Oscillators that operate at 720 and 940 MHz and characterized over a temperature range of 25 °C to 200 °C and 250 °C, respectively, are presented. The oscillators are designed on alumina substrates with typical integrated circuit fabrication techniques. Cree SiC MESFETs, thin film metal-insulator-metal capacitors and spiral inductors, and Johanson miniature chip antennas make-up the circuits. The output power and phase noise are presented as a function of temperature and frequency.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114499475","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725023
R. Feger, E. Kolmhofer, F. Starzer, Friedrich Wiesinger, S. Scheiblhofer, A. Stelzer
This contribution describes the realization of a heterodyne frequency-modulated continuous-wave (FMCW) radar system operating in the frequency band from 76 GHz to 77 GHz. To implement the heterodyne principle two voltage controlled oscillators (VCOs) are operated in order to produce frequency ramp signals with a fixed frequency offset. This allows to mitigate effects occurring in homodyne systems like, e.g., DC-offsets or low-frequency noise components. To avoid large divider values in the control loop the presented system is based on an offset phase-locked-loop configuration. In the presented implementation the same downconverter is used to implement the offset-loop for both VCOs, which has the positive effect that errors and noise influences in the downconversion process—at least partly—cancel out in the final FMCW output signal.
{"title":"A heterodyne 77-GHz FMCW radar with offset PLL frequency stabilization","authors":"R. Feger, E. Kolmhofer, F. Starzer, Friedrich Wiesinger, S. Scheiblhofer, A. Stelzer","doi":"10.1109/WISNET.2011.5725023","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725023","url":null,"abstract":"This contribution describes the realization of a heterodyne frequency-modulated continuous-wave (FMCW) radar system operating in the frequency band from 76 GHz to 77 GHz. To implement the heterodyne principle two voltage controlled oscillators (VCOs) are operated in order to produce frequency ramp signals with a fixed frequency offset. This allows to mitigate effects occurring in homodyne systems like, e.g., DC-offsets or low-frequency noise components. To avoid large divider values in the control loop the presented system is based on an offset phase-locked-loop configuration. In the presented implementation the same downconverter is used to implement the offset-loop for both VCOs, which has the positive effect that errors and noise influences in the downconversion process—at least partly—cancel out in the final FMCW output signal.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121768367","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725019
Hao Gao, P. Baltus, R. Mahmoudi, A. V. van Roermund
This paper presents the analysis of the performance of charge pump, and the design strategy and efficiency optimization of 2.4GHz micro-power charge pump using 65nm CMOS technology. The model of the charge pump takes account of the threshold voltage variation, bulk modulation, and the major parasitic capacitor. Charge pump is sensitive to the input voltage swing and the actual input voltage swing is less after the capacitor divider, which generates the optimized size transistor. From the mathematic model of the charge pump, the relationship between the charge pump performance and design parameter is presented. After parameter analysis and performance discussion, a design procedure to maximize performance is presented. Corresponding to the design procedure presented in this paper, a high efficiency charge pump at 2.4GHz is presented.
{"title":"2.4GHz energy harvesting for wireless sensor network","authors":"Hao Gao, P. Baltus, R. Mahmoudi, A. V. van Roermund","doi":"10.1109/WISNET.2011.5725019","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725019","url":null,"abstract":"This paper presents the analysis of the performance of charge pump, and the design strategy and efficiency optimization of 2.4GHz micro-power charge pump using 65nm CMOS technology. The model of the charge pump takes account of the threshold voltage variation, bulk modulation, and the major parasitic capacitor. Charge pump is sensitive to the input voltage swing and the actual input voltage swing is less after the capacitor divider, which generates the optimized size transistor. From the mathematic model of the charge pump, the relationship between the charge pump performance and design parameter is presented. After parameter analysis and performance discussion, a design procedure to maximize performance is presented. Corresponding to the design procedure presented in this paper, a high efficiency charge pump at 2.4GHz is presented.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125459773","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 : 2011-03-07DOI: 10.1109/WISNET.2011.5725024
C. Reck, U. Berold, L. Schmidt
Methods to estimate Directions of Arrival (DOA) on radio signals are susceptible to hardware and signal deficiencies. In the following, the robustness of four algorithms is evaluated by numerical and experimental tests. The focus lies thereby on Secondary Surveillance Radar (SSR) signals, but the algorithms can generally be used on any kind of radio signal. It will be shown that variants of the ESPRIT algorithm provide highly accurate DOA estimates on SSR signals even without calibration.
{"title":"Robust DOA estimation of SSR signals for aircraft positioning","authors":"C. Reck, U. Berold, L. Schmidt","doi":"10.1109/WISNET.2011.5725024","DOIUrl":"https://doi.org/10.1109/WISNET.2011.5725024","url":null,"abstract":"Methods to estimate Directions of Arrival (DOA) on radio signals are susceptible to hardware and signal deficiencies. In the following, the robustness of four algorithms is evaluated by numerical and experimental tests. The focus lies thereby on Secondary Surveillance Radar (SSR) signals, but the algorithms can generally be used on any kind of radio signal. It will be shown that variants of the ESPRIT algorithm provide highly accurate DOA estimates on SSR signals even without calibration.","PeriodicalId":128026,"journal":{"name":"2011 IEEE Topical Conference on Wireless Sensors and Sensor Networks","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123707640","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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