Pub Date : 2011-03-28DOI: 10.1109/SAS.2011.5739793
Chintan M. Bhatt, N. Jampana
Polypyrrole (PPy) is one of the important conductive polymer (CP) that is widely used in gas sensing applications. It exhibits reversible changes in its direct current (DC) resistance on exposure to variety of organic vapors and gases, but the environmental stability of its resistive property is found poor. Hence polypyrrole based gas sensor is designed and its electrical properties against ethanol as an analyte has been studied. Polypyrrole is electrodeposited on interdigital gold electrode structure with potassium chloride (1M KCl) as an electrolyte using chronocoulometry. Electrical impedance spectroscopy technique is used to study electrical properties of the sensor over a frequency range 10 Hz to 2 MHz. The sensor response is monitored by measuring the changes in its impedance i.e., capacitance and resistance of the sensor upon exposure to organic vapor molecules. It is observed that the capacitive property of the sensor is more sensitive to the ethanol than its resistive property. Effect of aging on the electrical properties of the sensor is also studied and found that the capacitance has less effect with aging than its resistive property.
{"title":"Comparative studies on electrical properties of Polypyrrole based gas sensor","authors":"Chintan M. Bhatt, N. Jampana","doi":"10.1109/SAS.2011.5739793","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739793","url":null,"abstract":"Polypyrrole (PPy) is one of the important conductive polymer (CP) that is widely used in gas sensing applications. It exhibits reversible changes in its direct current (DC) resistance on exposure to variety of organic vapors and gases, but the environmental stability of its resistive property is found poor. Hence polypyrrole based gas sensor is designed and its electrical properties against ethanol as an analyte has been studied. Polypyrrole is electrodeposited on interdigital gold electrode structure with potassium chloride (1M KCl) as an electrolyte using chronocoulometry. Electrical impedance spectroscopy technique is used to study electrical properties of the sensor over a frequency range 10 Hz to 2 MHz. The sensor response is monitored by measuring the changes in its impedance i.e., capacitance and resistance of the sensor upon exposure to organic vapor molecules. It is observed that the capacitive property of the sensor is more sensitive to the ethanol than its resistive property. Effect of aging on the electrical properties of the sensor is also studied and found that the capacitance has less effect with aging than its resistive property.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117265776","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739820
M. Habibi
The correlation image sensor (CIS) is an important device for detection of modulated light signals at high frame rates. In this paper a demodulation pixel is presented which increases the sensitivity of the CIS device. The pixel is capable of detecting and demodulating light signals at lower illumination levels compared with the previous designs. Furthermore due to the low number of processing stages the random noise at the output remains close to the kT/C reset and photodiode shot noise. The presented design is compared with previous solutions under similar operating conditions using a 0.35µm standard CMOS technology. It is shown that while the fill factor and power consumption of the design is close to the previous structures, it is able to operate at lower modulated illumination levels and higher dynamic range of background intensities.
{"title":"A high sensitivity correlation image sensor","authors":"M. Habibi","doi":"10.1109/SAS.2011.5739820","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739820","url":null,"abstract":"The correlation image sensor (CIS) is an important device for detection of modulated light signals at high frame rates. In this paper a demodulation pixel is presented which increases the sensitivity of the CIS device. The pixel is capable of detecting and demodulating light signals at lower illumination levels compared with the previous designs. Furthermore due to the low number of processing stages the random noise at the output remains close to the kT/C reset and photodiode shot noise. The presented design is compared with previous solutions under similar operating conditions using a 0.35µm standard CMOS technology. It is shown that while the fill factor and power consumption of the design is close to the previous structures, it is able to operate at lower modulated illumination levels and higher dynamic range of background intensities.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127673218","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739801
Wei Cai, Jeremy Chan, D. Garmire
A 3-axes Hall-effect sensor was fabricated using the PolyMUMPs process based on the MEMS design software, Coventorware. We document the fabrication of this MEMS device and report its preliminary performance based on comparisons to a laboratory Gauss meter.
{"title":"3-axes MEMS Hall-effect sensor","authors":"Wei Cai, Jeremy Chan, D. Garmire","doi":"10.1109/SAS.2011.5739801","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739801","url":null,"abstract":"A 3-axes Hall-effect sensor was fabricated using the PolyMUMPs process based on the MEMS design software, Coventorware. We document the fabrication of this MEMS device and report its preliminary performance based on comparisons to a laboratory Gauss meter.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127305411","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739789
Jinyi Lee, S. Kwon
An improvement has to be made in the inspection speed and the crack detection ability needed to inspect cracks in express train wheels. In this paper a linearly integrated Hall sensor array (LIHaS) is proposed in order to improve the ability for crack detection. In addition, the exclusive parallel signal conditioning circuits, the analog-to-digital convertors, and the interface were developed to reduce the measurement time. The permanent magnet, which applies the vertical magnetic field to the wheel, and the differential-type LIHaS, which measures the distribution of the magnetic field around a crack, is designed to be buried in the rail. An experiment was performed in order to verify the proposed method.
{"title":"Non-destructive testing of a train wheel using a linearly integrated Hall sensor array","authors":"Jinyi Lee, S. Kwon","doi":"10.1109/SAS.2011.5739789","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739789","url":null,"abstract":"An improvement has to be made in the inspection speed and the crack detection ability needed to inspect cracks in express train wheels. In this paper a linearly integrated Hall sensor array (LIHaS) is proposed in order to improve the ability for crack detection. In addition, the exclusive parallel signal conditioning circuits, the analog-to-digital convertors, and the interface were developed to reduce the measurement time. The permanent magnet, which applies the vertical magnetic field to the wheel, and the differential-type LIHaS, which measures the distribution of the magnetic field around a crack, is designed to be buried in the rail. An experiment was performed in order to verify the proposed method.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124898655","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739821
G. Willden, Donald Poole, B. Abbott, Ronald T. Green
Prior papers have described prototype sensors that were developed to autonomously map pathway, flow velocity, and dimensions as they flow through karst conduits. The prototype sensors are equipped with sonar and magnetometers to measure conduit morphology and orientation. The sensors are developed to be approximately neutrally buoyant but have been equipped with a propulsion system to enable the sensors to negotiate around impediments in the flow channel and avoid stalling at the walls of the conduit or cave. Data collected during an excursion are downloaded from the sensor upon completion of the survey mission. An autonomous sensor was successfully used to characterize a segment in Honey Creek Cave, a wet cave in south-central Texas. Sonar proved to be effective in measuring the cave dimensions and the velocity of flow. A magnetometer was used to orient the pathway taken by the sensor. Together, these data provided a representative reproduction of the oriented morphology of the wet cave. Two variations of the initial generation of sensors have been developed to meet the requirements of projects funded by the United States Army Corps of Engineers for mapping borehole-accessed karst solution cavities and by the Federal Highway Administration for mapping, monitoring, and diagnosing damage to roadway culverts. The first variation is tethered to map karst voids intersected by a drill hole but where discharge to a spring is not anticipated. The second features an enhanced sonar scheme to overcome the extreme multipath environments found inside a partially filled metal culvert and to provide localization information in a magnetically shielded environment.
{"title":"Mapping borehole-accessed karst solutional features and culvert conduits using remote sensor technology","authors":"G. Willden, Donald Poole, B. Abbott, Ronald T. Green","doi":"10.1109/SAS.2011.5739821","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739821","url":null,"abstract":"Prior papers have described prototype sensors that were developed to autonomously map pathway, flow velocity, and dimensions as they flow through karst conduits. The prototype sensors are equipped with sonar and magnetometers to measure conduit morphology and orientation. The sensors are developed to be approximately neutrally buoyant but have been equipped with a propulsion system to enable the sensors to negotiate around impediments in the flow channel and avoid stalling at the walls of the conduit or cave. Data collected during an excursion are downloaded from the sensor upon completion of the survey mission. An autonomous sensor was successfully used to characterize a segment in Honey Creek Cave, a wet cave in south-central Texas. Sonar proved to be effective in measuring the cave dimensions and the velocity of flow. A magnetometer was used to orient the pathway taken by the sensor. Together, these data provided a representative reproduction of the oriented morphology of the wet cave. Two variations of the initial generation of sensors have been developed to meet the requirements of projects funded by the United States Army Corps of Engineers for mapping borehole-accessed karst solution cavities and by the Federal Highway Administration for mapping, monitoring, and diagnosing damage to roadway culverts. The first variation is tethered to map karst voids intersected by a drill hole but where discharge to a spring is not anticipated. The second features an enhanced sonar scheme to overcome the extreme multipath environments found inside a partially filled metal culvert and to provide localization information in a magnetically shielded environment.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130511358","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739786
Kyohei Ota, Yuki Ota, Mitsugu Otsu, A. Kajiwara
Requirement for monitoring the state of the elderly in care facilities is increasing year by year and the increase in accidents involving them becomes great concern. In this paper, an ultra-wideband impulse-radio (UWB-IR) monitoring sensor is suggested which focuses on the bed status most critical to the elderly that need the assistance immediately. Employing our developed state detection algorithm based on ranging and motion estimation, the state can be detected that includes sleeping in a bed, sitting up in bed, falling down, wandering in room, going in and out at the door. The measurements were conducted in care facilities and the detection performance about the above mentioned state is investigated where various scenarios are considered. The measurement result shows that the detection rate is more than 95%.
{"title":"Elderly-care motion sensor using UWB-IR","authors":"Kyohei Ota, Yuki Ota, Mitsugu Otsu, A. Kajiwara","doi":"10.1109/SAS.2011.5739786","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739786","url":null,"abstract":"Requirement for monitoring the state of the elderly in care facilities is increasing year by year and the increase in accidents involving them becomes great concern. In this paper, an ultra-wideband impulse-radio (UWB-IR) monitoring sensor is suggested which focuses on the bed status most critical to the elderly that need the assistance immediately. Employing our developed state detection algorithm based on ranging and motion estimation, the state can be detected that includes sleeping in a bed, sitting up in bed, falling down, wandering in room, going in and out at the door. The measurements were conducted in care facilities and the detection performance about the above mentioned state is investigated where various scenarios are considered. The measurement result shows that the detection rate is more than 95%.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124669837","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739779
Yongwoo Jeong, A. Titus
In this work we describe the design and testing of a custom CMOS-based motion detection system that derives its functionality from biology. The system will beone component of a CMOS visual sensor system that will identify and foveate on objects. The system is inspired by different animals that perform similar functions and have similar retinal structures. For example, we mimic frog's eye using a hemispherical surface structure to provide a wider field of view. In addition, we mimic the human retina with a combination of fovea and peripheral light detectors. The result is a sensor array that combines these aspects to attend and foveate on objects of interest.
{"title":"Biological inspired CMOS foveated sensor: For neural network training","authors":"Yongwoo Jeong, A. Titus","doi":"10.1109/SAS.2011.5739779","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739779","url":null,"abstract":"In this work we describe the design and testing of a custom CMOS-based motion detection system that derives its functionality from biology. The system will beone component of a CMOS visual sensor system that will identify and foveate on objects. The system is inspired by different animals that perform similar functions and have similar retinal structures. For example, we mimic frog's eye using a hemispherical surface structure to provide a wider field of view. In addition, we mimic the human retina with a combination of fovea and peripheral light detectors. The result is a sensor array that combines these aspects to attend and foveate on objects of interest.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125986142","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739806
C. De Dominicis, A. Flammini, E. Sisinni, L. Fasanotti, F. Floreani
The growing interest towards green and efficient use of electrical energy has recently pushed the industry of street light control systems. In the past, very simple on/off switching mechanism based on daylight sensing and cyclic preventive maintenance procedures were adopted. Nowadays, intelligent control systems offering remote supervision have strongly contributed to a change in perspective in maintenance engineering form a traditional “Fail and Fix” view to a “Predict and Prevent” approach. However, most of the infrastructure is already in place and replace street light with improved units has to be economical feasible. Traditional solutions exploit Power Line Communications (PLCs). In this paper we propose a wireless retrofitting of lamps, which has some advantages due to the independence from power line faults. In addition, the service provider usually ignores the exact location of the lamp poles and the integration with Geographic Information System (GIS) databases requires a preliminary on-site survey. The novelty of our proposal relies on the exploitation of nodes self location capability. Radios based on Chirp Spread Spectrum (CSS) modulation are used in order to achieve a good spatial resolution without the adoption of expensive GPS modules. In particular, experimental results are focused on the ranging capabilities of such devices, showing the feasibility of the proposed approach. Open field trials, mimicking real world applications, have shown an overall accuracy on the order of one meter.
{"title":"On the development of a wireless self localizing streetlight monitoring system","authors":"C. De Dominicis, A. Flammini, E. Sisinni, L. Fasanotti, F. Floreani","doi":"10.1109/SAS.2011.5739806","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739806","url":null,"abstract":"The growing interest towards green and efficient use of electrical energy has recently pushed the industry of street light control systems. In the past, very simple on/off switching mechanism based on daylight sensing and cyclic preventive maintenance procedures were adopted. Nowadays, intelligent control systems offering remote supervision have strongly contributed to a change in perspective in maintenance engineering form a traditional “Fail and Fix” view to a “Predict and Prevent” approach. However, most of the infrastructure is already in place and replace street light with improved units has to be economical feasible. Traditional solutions exploit Power Line Communications (PLCs). In this paper we propose a wireless retrofitting of lamps, which has some advantages due to the independence from power line faults. In addition, the service provider usually ignores the exact location of the lamp poles and the integration with Geographic Information System (GIS) databases requires a preliminary on-site survey. The novelty of our proposal relies on the exploitation of nodes self location capability. Radios based on Chirp Spread Spectrum (CSS) modulation are used in order to achieve a good spatial resolution without the adoption of expensive GPS modules. In particular, experimental results are focused on the ranging capabilities of such devices, showing the feasibility of the proposed approach. Open field trials, mimicking real world applications, have shown an overall accuracy on the order of one meter.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"PC-29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126681245","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739800
V. Mašek, M. Čada, Andrew Cook, Wu Nan, Dan Li
A novel concept of using a fiber optic technology to create a 3-D seismometer/accelerometer was proposed. The initial planar prototype exhibits a good linearity in the static calibration and less noisy signal in low-frequency dynamic tests. In the near future, a 3-D prototype will be subjected to a large set of tests in an environmental chamber to find the sensors output correlation/immunity to different ambient conditions such as temperature and humidity.
{"title":"Fibre optic based 3-D accelerometer design","authors":"V. Mašek, M. Čada, Andrew Cook, Wu Nan, Dan Li","doi":"10.1109/SAS.2011.5739800","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739800","url":null,"abstract":"A novel concept of using a fiber optic technology to create a 3-D seismometer/accelerometer was proposed. The initial planar prototype exhibits a good linearity in the static calibration and less noisy signal in low-frequency dynamic tests. In the near future, a 3-D prototype will be subjected to a large set of tests in an environmental chamber to find the sensors output correlation/immunity to different ambient conditions such as temperature and humidity.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114775079","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 : 2011-03-28DOI: 10.1109/SAS.2011.5739767
A. Abdelgawad, M. Bayoumi
Installation of a system to monitor and measure sand production from an oil well would be valuable to assist in optimizing well productivity and to detect sand as early as possible. In this paper we present a framework for sand monitoring using Wireless Sensor Network (WSN). The framework combines two modules: a Sand Rate Calculation (SRC) module and a Distributed Data Fusion (DDF) module. The framework is designed to collect data from oil pipeline using acoustic sensors (SENACO AS100) in real time. A test bed was established from ten acoustic sensors mounted on a closed loop pipeline. Each acoustic sensor is attached to WSN node. Each node calculates its local sand rate using SRC module. Every node sends its sand rate to the neighbors. The DDF module at each node is using its own local sand rate and the neighbors' sand rate to calculate the global sand rate. The DDF is implemented using a Distributed Kalman Filter (DKF). The proposed framework was successfully evaluated throughout experimental tests.
{"title":"Sand monitoring in pipelines using Distributed Data Fusion algorithm","authors":"A. Abdelgawad, M. Bayoumi","doi":"10.1109/SAS.2011.5739767","DOIUrl":"https://doi.org/10.1109/SAS.2011.5739767","url":null,"abstract":"Installation of a system to monitor and measure sand production from an oil well would be valuable to assist in optimizing well productivity and to detect sand as early as possible. In this paper we present a framework for sand monitoring using Wireless Sensor Network (WSN). The framework combines two modules: a Sand Rate Calculation (SRC) module and a Distributed Data Fusion (DDF) module. The framework is designed to collect data from oil pipeline using acoustic sensors (SENACO AS100) in real time. A test bed was established from ten acoustic sensors mounted on a closed loop pipeline. Each acoustic sensor is attached to WSN node. Each node calculates its local sand rate using SRC module. Every node sends its sand rate to the neighbors. The DDF module at each node is using its own local sand rate and the neighbors' sand rate to calculate the global sand rate. The DDF is implemented using a Distributed Kalman Filter (DKF). The proposed framework was successfully evaluated throughout experimental tests.","PeriodicalId":401849,"journal":{"name":"2011 IEEE Sensors Applications Symposium","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124273613","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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