Pub Date : 2012-05-10DOI: 10.1109/IMWS.2012.6215829
A. Costanzo, L. Roselli
This contribution discusses different aspects related to EM- and piezo-scavengers from ambient energy that are very promising as power suppliers of the latest evolution of ultra-low power electronic systems. First challenges in designing circuits and systems for microwave ambient energy harvesting are discussed. A design flow, including the RF/Microwave receivers and the base-band conversion blocks is presented. Power densities as low as few μW/cm2 are targeted as realistic sources to be scavenged by a highly efficient multi-band resonant rectenna. Predicted and measured results in stationary regime are presented and the measured converted energy is also assessed. Second, a conventional piezoelectric scavenger is tested as a power source of a nomadic RFID-reader adopted for novel localization system approach. The latter is intended as an example of multidisciplinary (RFID-NFC, ultra-low power systems, short range wireless power transfer, organic technologies and so on), fully autonomous (energy scavenger on board, battery-less), wirelessly empowered (multitude of passive tags is energized by autonomous reader), evolutionary electronic system toward a “greener world”.
{"title":"EM- and piezo-scavengers: Two useful solutions in highly humanized scenarios toward a \"greener world\"","authors":"A. Costanzo, L. Roselli","doi":"10.1109/IMWS.2012.6215829","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215829","url":null,"abstract":"This contribution discusses different aspects related to EM- and piezo-scavengers from ambient energy that are very promising as power suppliers of the latest evolution of ultra-low power electronic systems. First challenges in designing circuits and systems for microwave ambient energy harvesting are discussed. A design flow, including the RF/Microwave receivers and the base-band conversion blocks is presented. Power densities as low as few μW/cm2 are targeted as realistic sources to be scavenged by a highly efficient multi-band resonant rectenna. Predicted and measured results in stationary regime are presented and the measured converted energy is also assessed. Second, a conventional piezoelectric scavenger is tested as a power source of a nomadic RFID-reader adopted for novel localization system approach. The latter is intended as an example of multidisciplinary (RFID-NFC, ultra-low power systems, short range wireless power transfer, organic technologies and so on), fully autonomous (energy scavenger on board, battery-less), wirelessly empowered (multitude of passive tags is energized by autonomous reader), evolutionary electronic system toward a “greener world”.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"39 5 1","pages":"15-18"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76063538","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215800
T. Ishida, K. Yamaguchi, T. Ishizaki, I. Awai
A measurement method for wireless power transfer (WPT) system with 0-ohm source impedance is shown. WPT systems are often designed by the BPF design theory and a vector network analyzer (VNA) is normally used for measurement. Here, some difficulty comes up for 0-ohm system that is common for high-efficient switching power sources. This paper describes the transmitted power and the transmission efficiency of 0-ohm system which are calculated by S parameters measured by VNA. The method is very simple and is applicable not only for 0-ohm system, but also for other impedance systems.
{"title":"Novel measurement technique of WPT circuits using VNA and its data transformation into 0-ohm system","authors":"T. Ishida, K. Yamaguchi, T. Ishizaki, I. Awai","doi":"10.1109/IMWS.2012.6215800","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215800","url":null,"abstract":"A measurement method for wireless power transfer (WPT) system with 0-ohm source impedance is shown. WPT systems are often designed by the BPF design theory and a vector network analyzer (VNA) is normally used for measurement. Here, some difficulty comes up for 0-ohm system that is common for high-efficient switching power sources. This paper describes the transmitted power and the transmission efficiency of 0-ohm system which are calculated by S parameters measured by VNA. The method is very simple and is applicable not only for 0-ohm system, but also for other impedance systems.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"11 1","pages":"231-234"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89722042","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215790
K. Maki, M. Takahashi, K. Miyashiro, K. Tanaka, S. Sasaki, K. Kawahara, Y. Kamata, K. Komurasaki
Toward the orbital demonstration of a solar power satellite (SPS), a breadboard model of the SPS has been developed for preliminary experiments including wireless power transmission. The model forms a thin panel structure with a thickness of 6 cm, and the panel consists of three layers being functionally assigned to a transmission antenna, microwave amplification and control, and thermal radiation, respectively. Microwave amplified up to 160 W is emitted from a large-scale phased array antenna with 256 microstrip elements. In order to evaluate the effect of multiply arranged antennas to the emission, the measurement of the radiation pattern is conducted for different relative positions of the antenna panels. Additionally, the steering of the transmission beam is achieved as an initial demonstration for retrodirective control.
{"title":"Microwave characteristics of a wireless power transmission panel toward the orbital experiment of a solar power satellite","authors":"K. Maki, M. Takahashi, K. Miyashiro, K. Tanaka, S. Sasaki, K. Kawahara, Y. Kamata, K. Komurasaki","doi":"10.1109/IMWS.2012.6215790","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215790","url":null,"abstract":"Toward the orbital demonstration of a solar power satellite (SPS), a breadboard model of the SPS has been developed for preliminary experiments including wireless power transmission. The model forms a thin panel structure with a thickness of 6 cm, and the panel consists of three layers being functionally assigned to a transmission antenna, microwave amplification and control, and thermal radiation, respectively. Microwave amplified up to 160 W is emitted from a large-scale phased array antenna with 256 microstrip elements. In order to evaluate the effect of multiply arranged antennas to the emission, the measurement of the radiation pattern is conducted for different relative positions of the antenna panels. Additionally, the steering of the transmission beam is achieved as an initial demonstration for retrodirective control.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"15 1","pages":"131-134"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87832841","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215780
K. Hayashino, K. Harauchi, Y. Iwasaki, K. Fukui, J. Ao, Y. Ohno
Comparing circuit simulation results, an analytical model for the efficiency of single shunt rectenna circuits is developed. The model estimates the DC output power and loss power in rectenna circuits and gives good agreements with circuit simulation results. With this model, the effect of signal frequency and the diode capacitance is clarified.
{"title":"Analysis of loss mechanism in rectenna circuit with GaN Schottky barrier diode","authors":"K. Hayashino, K. Harauchi, Y. Iwasaki, K. Fukui, J. Ao, Y. Ohno","doi":"10.1109/IMWS.2012.6215780","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215780","url":null,"abstract":"Comparing circuit simulation results, an analytical model for the efficiency of single shunt rectenna circuits is developed. The model estimates the DC output power and loss power in rectenna circuits and gives good agreements with circuit simulation results. With this model, the effect of signal frequency and the diode capacitance is clarified.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"46 1","pages":"179-182"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89141125","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215794
Y. Kubo, N. Shinohara, T. Mitani
We first have introduced a microwave wireless power supply system charging electric vehicles and described transmitting antennas suitable for the system. The aim of this paper is partly to find out the performance limit of a single antenna, instead of an array antenna. Five kinds of antennas have been designed and simulated on Ansoft HFSS in order to examine their usefulness as a candidate for transmittion: a rectangular horn, followed by a rectangular horn loading an E plane metal-plate lens, a conical horn loading a dielectric lens, a corrugated horn, and a corrugated horn loading a dielectric lens. We have confirmed that a higher directivity can be achieved when antennas are loading a metal lens or a dielectric lens. In such cases, however, the scattering occurs, even if the reflection coefficient is very low. Further improvement still needs to be done in future.
{"title":"Development of a kW class microwave wireless power supply system to a vehicle roof","authors":"Y. Kubo, N. Shinohara, T. Mitani","doi":"10.1109/IMWS.2012.6215794","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215794","url":null,"abstract":"We first have introduced a microwave wireless power supply system charging electric vehicles and described transmitting antennas suitable for the system. The aim of this paper is partly to find out the performance limit of a single antenna, instead of an array antenna. Five kinds of antennas have been designed and simulated on Ansoft HFSS in order to examine their usefulness as a candidate for transmittion: a rectangular horn, followed by a rectangular horn loading an E plane metal-plate lens, a conical horn loading a dielectric lens, a corrugated horn, and a corrugated horn loading a dielectric lens. We have confirmed that a higher directivity can be achieved when antennas are loading a metal lens or a dielectric lens. In such cases, however, the scattering occurs, even if the reflection coefficient is very low. Further improvement still needs to be done in future.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"27 3","pages":"205-208"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91438804","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215788
E. Narita, T. Sakurai, Y. Suzuki, M. Taki, J. Miyakoshi
The relationship between exposure to electromagnetic fields (EMF) and health risks is of increasing interest. Although general concern regarding the potential hazards of exposure to an EMF has led to many epidemiological investigations, the effects of EMF exposure on human cells are still controversial. In vitro study, the cellular immune effects of EMF are discussed. We investigated the effects of a high-frequency electromagnetic field (HFEMF) at 2.45 GHz on cytokine (such as, human interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), and tumor necrosis factor-α (TNF-α)) productions in human monoblastic U937 cells. Our results showed that the exposure to a HFEMF of 2.45 GHz at SAR of 2 and 10 W/kg for 4 and 24 hours has no significant effect on IL-1β, IL-6, IL-8, IL-10 and TNF-α productions in U937 cells.
{"title":"Influence of a high-frequency electromagnetic field at 2.45 GHz on cytokine productions in macrophage-like U937 cells","authors":"E. Narita, T. Sakurai, Y. Suzuki, M. Taki, J. Miyakoshi","doi":"10.1109/IMWS.2012.6215788","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215788","url":null,"abstract":"The relationship between exposure to electromagnetic fields (EMF) and health risks is of increasing interest. Although general concern regarding the potential hazards of exposure to an EMF has led to many epidemiological investigations, the effects of EMF exposure on human cells are still controversial. In vitro study, the cellular immune effects of EMF are discussed. We investigated the effects of a high-frequency electromagnetic field (HFEMF) at 2.45 GHz on cytokine (such as, human interleukin 1β (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), and tumor necrosis factor-α (TNF-α)) productions in human monoblastic U937 cells. Our results showed that the exposure to a HFEMF of 2.45 GHz at SAR of 2 and 10 W/kg for 4 and 24 hours has no significant effect on IL-1β, IL-6, IL-8, IL-10 and TNF-α productions in U937 cells.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"567 1","pages":"123-126"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91354734","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215795
T. Ichihara, T. Mitani, N. Shinohara
The objective of the present study is to drive or charge a ZigBee device by intermittent microwave power transmission, which is compatible with the wireless sensor network. We found out that intermittent microwave power transmission drove the rectifier circuit with high efficiency at the average consumed power of the ZigBee devices. Also we confirmed that the ZigBee device could communicate correctly in high power density with intermittent microwave irradiation; whereas it could not communicate robustly in slight power density with continuous microwave irradiation. We finally demonstrated that the ZigBee device worked and communicated correctly without a battery by intermittent microwave power transmission.
{"title":"Study on intermittent microwave power transmission to a ZigBee device","authors":"T. Ichihara, T. Mitani, N. Shinohara","doi":"10.1109/IMWS.2012.6215795","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215795","url":null,"abstract":"The objective of the present study is to drive or charge a ZigBee device by intermittent microwave power transmission, which is compatible with the wireless sensor network. We found out that intermittent microwave power transmission drove the rectifier circuit with high efficiency at the average consumed power of the ZigBee devices. Also we confirmed that the ZigBee device could communicate correctly in high power density with intermittent microwave irradiation; whereas it could not communicate robustly in slight power density with continuous microwave irradiation. We finally demonstrated that the ZigBee device worked and communicated correctly without a battery by intermittent microwave power transmission.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"53 1","pages":"209-212"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86242884","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215805
K. Ogawa, K. Ozaki, M. Yamada, K. Honda
This paper presents experimental studies on the improvement of efficiency of the small-sized rectenna using an LC resonator having high-Q characteristics at 950 MHz. The developed rectenna has a feature of its compactness with the dimensions of 20 mm × 13 mm. By choosing an optimum LC combination, the RF-DC conversion efficiency of 85.6 % at a 10-mW input power has been attained. Furthermore, at a low input power of 1 mW and 0.1 mW, the RF-DC conversion efficiency of 73.2% and 40% has been achieved. Using the developed rectenna, experiments on long distance wireless power transmission were performed, and its ability to transmit power to distant wireless devices in an actual radio wave propagation environment was confirmed.
{"title":"High efficiency small-sized rectenna using a high-Q LC resonator for long distance WPT at 950 MHz","authors":"K. Ogawa, K. Ozaki, M. Yamada, K. Honda","doi":"10.1109/IMWS.2012.6215805","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215805","url":null,"abstract":"This paper presents experimental studies on the improvement of efficiency of the small-sized rectenna using an LC resonator having high-Q characteristics at 950 MHz. The developed rectenna has a feature of its compactness with the dimensions of 20 mm × 13 mm. By choosing an optimum LC combination, the RF-DC conversion efficiency of 85.6 % at a 10-mW input power has been attained. Furthermore, at a low input power of 1 mW and 0.1 mW, the RF-DC conversion efficiency of 73.2% and 40% has been achieved. Using the developed rectenna, experiments on long distance wireless power transmission were performed, and its ability to transmit power to distant wireless devices in an actual radio wave propagation environment was confirmed.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"56 1","pages":"255-258"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87067797","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215828
Kamil A. Grajski, Ryan Tseng, Chuck Wheatley
Loosely-coupled (LC) wireless power transfer (WPT) offers unique, next-generation improvements in user experience, and product design and innovation towards the vision of ubiquitous power, and infinite stand-by time for a wide range of consumer electronic devices. We outline the vision as it relates to today's mobile, battery-powered, hand-held, consumer electronics devices, and consider the unique capabilities of loosely-coupled (LC) WPT. We then describe the physics of the magnetically coupled resonant coil subsystem, which lies at the heart of LC WPT, discuss approaches and challenges in implementing WPT electronic circuits, and review industry progress towards timely, high-quality WPT technical standards.
{"title":"Loosely-coupled wireless power transfer: Physics, circuits, standards","authors":"Kamil A. Grajski, Ryan Tseng, Chuck Wheatley","doi":"10.1109/IMWS.2012.6215828","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215828","url":null,"abstract":"Loosely-coupled (LC) wireless power transfer (WPT) offers unique, next-generation improvements in user experience, and product design and innovation towards the vision of ubiquitous power, and infinite stand-by time for a wide range of consumer electronic devices. We outline the vision as it relates to today's mobile, battery-powered, hand-held, consumer electronics devices, and consider the unique capabilities of loosely-coupled (LC) WPT. We then describe the physics of the magnetically coupled resonant coil subsystem, which lies at the heart of LC WPT, discuss approaches and challenges in implementing WPT electronic circuits, and review industry progress towards timely, high-quality WPT technical standards.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"31 1","pages":"9-14"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77755285","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 : 2012-05-10DOI: 10.1109/IMWS.2012.6215804
Changhyun Cho, Jonghyun Cho, Myunghoi Kim, Joungho Kim, J. Pak
In this paper, we present an on-chip embedded current probe that uses magnetic field coupling to determine the current flowing on a target channel without breaking the circuit. A helically wound 3 dimensional on chip inductor is adopted as a current probe. We first investigate the characteristics of mutual induction for this current probing structure in various geometrical design parameters like coupling distance, area of magnetic flux linkage and ratio of turns. And then we describe how to process the magnetically induced voltage to reconstruct a current waveform. Finally we validate the performance of proposed on-chip current probe by the experimental results of test vehicle fabricated in PCB.
{"title":"Design and implementation of on-chip embedded current probe using magnetic field coupling in chip to chip wireless power transfer system","authors":"Changhyun Cho, Jonghyun Cho, Myunghoi Kim, Joungho Kim, J. Pak","doi":"10.1109/IMWS.2012.6215804","DOIUrl":"https://doi.org/10.1109/IMWS.2012.6215804","url":null,"abstract":"In this paper, we present an on-chip embedded current probe that uses magnetic field coupling to determine the current flowing on a target channel without breaking the circuit. A helically wound 3 dimensional on chip inductor is adopted as a current probe. We first investigate the characteristics of mutual induction for this current probing structure in various geometrical design parameters like coupling distance, area of magnetic flux linkage and ratio of turns. And then we describe how to process the magnetically induced voltage to reconstruct a current waveform. Finally we validate the performance of proposed on-chip current probe by the experimental results of test vehicle fabricated in PCB.","PeriodicalId":6308,"journal":{"name":"2012 IEEE MTT-S International Microwave Workshop Series on Innovative Wireless Power Transmission: Technologies, Systems, and Applications","volume":"08 1","pages":"249-252"},"PeriodicalIF":0.0,"publicationDate":"2012-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81068747","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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