Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235106
A. Hussein, L. Alnaggar, M. Abd-Elnaby
Most of the recent state of the art circular antenna arrays (CAA) synthesis techniques attempted to synthesize the Chebyshev linear array patterns in the azimuth plane. In this paper, a new Genetic algorithm optimization-based technique for Uniform CAAs synthesis to realize a desired Chebyshev pattern in the elevation plane is introduced. The proposed technique maintains the same number of antenna elements as the linear antenna array. While the CAA diameter, elements angular distribution, and elements excitations are optimized to synthesize the desired pattern. The CAA diameter is optimized around the array size of the linear antenna array. And the angular positions of the antenna elements are non-uniformly distributed on the circle circumference using the GA optimization. While a closed-form expression for the corresponding elements excitations is derived to determine these excitations using a deterministic equation solving technique. Several simulations are performed to verify the effectiveness of the proposed technique.
{"title":"Synthesis of Circular Antenna Arrays for Realization of Broadside Chebyshev Linear Array Patterns in the Elevation Plane","authors":"A. Hussein, L. Alnaggar, M. Abd-Elnaby","doi":"10.1109/NRSC49500.2020.9235106","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235106","url":null,"abstract":"Most of the recent state of the art circular antenna arrays (CAA) synthesis techniques attempted to synthesize the Chebyshev linear array patterns in the azimuth plane. In this paper, a new Genetic algorithm optimization-based technique for Uniform CAAs synthesis to realize a desired Chebyshev pattern in the elevation plane is introduced. The proposed technique maintains the same number of antenna elements as the linear antenna array. While the CAA diameter, elements angular distribution, and elements excitations are optimized to synthesize the desired pattern. The CAA diameter is optimized around the array size of the linear antenna array. And the angular positions of the antenna elements are non-uniformly distributed on the circle circumference using the GA optimization. While a closed-form expression for the corresponding elements excitations is derived to determine these excitations using a deterministic equation solving technique. Several simulations are performed to verify the effectiveness of the proposed technique.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"53 1","pages":"30-40"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89509598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235112
Fady Atef Naguib, S. Ahmed, Soha Hamed, M. Dessouky
This paper presents a new analog layout design tool for placement and routing of circuits using innovative template algorithm to decrease the solution space in an effective way then an optimization method to choose the best placement using satisfiability modulo theories SMT linear Solver. This tool is built in a way to consider the most advanced techniques used in today`s industrial products as well today advanced deep nodes to decrease the design cycle and layout iterations. This tool extracts the main sub-blocks types from the schematics then starts processing on each sub-block alone to find the best matching pattern that satisfies the block constraints and estimate the needed routing taking the parasitic into consideration, then using the SMT solver to find the best area to fit the design.
{"title":"Expert Guided Analog Layout Placement and Routing Automation for Deep Nanotechnologies","authors":"Fady Atef Naguib, S. Ahmed, Soha Hamed, M. Dessouky","doi":"10.1109/NRSC49500.2020.9235112","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235112","url":null,"abstract":"This paper presents a new analog layout design tool for placement and routing of circuits using innovative template algorithm to decrease the solution space in an effective way then an optimization method to choose the best placement using satisfiability modulo theories SMT linear Solver. This tool is built in a way to consider the most advanced techniques used in today`s industrial products as well today advanced deep nodes to decrease the design cycle and layout iterations. This tool extracts the main sub-blocks types from the schematics then starts processing on each sub-block alone to find the best matching pattern that satisfies the block constraints and estimate the needed routing taking the parasitic into consideration, then using the SMT solver to find the best area to fit the design.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"9 1","pages":"240-247"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80453745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235090
A. R. Eldamak, E. Fear
This paper presents a novel, low cost flexible paper substrate suitable for biosensing applications. A microstrip patch antenna consisting of copper tape foil and a cellulose filter paper as a substrate with thickness of 180 μm is fabricated and tested. The substrate has measured dielectric constant (εr) of 1.9 and losses (tan δ ) of 0.025. For 3.8 GHz resonance, the antenna has size of 29.5 mm x 38 mm on a ground plane of 50 mm x 60 mm. Measurements of the final design are in excellent agreement with simulations. Moreover, measurements of the patch antenna on the proposed substrate (cellulose filter paper) collected at different bending radii and folding angles demonstrate performance consistency.
本文提出了一种适用于生物传感应用的新型低成本柔性纸基板。制备了一种厚度为180 μm的微带贴片天线，并对其进行了测试。衬底的介电常数εr为1.9，损耗tan δ为0.025。3.8 GHz谐振时，天线尺寸为29.5 mm × 38mm，接平面为50mm × 60mm。最终设计的测量结果与模拟结果非常吻合。此外，在不同弯曲半径和折叠角度收集的基材(纤维素滤纸)上的贴片天线的测量结果表明性能一致。
{"title":"Flexible Patch Antennas on Filter Paper Substrate for Biosensing Applications","authors":"A. R. Eldamak, E. Fear","doi":"10.1109/NRSC49500.2020.9235090","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235090","url":null,"abstract":"This paper presents a novel, low cost flexible paper substrate suitable for biosensing applications. A microstrip patch antenna consisting of copper tape foil and a cellulose filter paper as a substrate with thickness of 180 μm is fabricated and tested. The substrate has measured dielectric constant (εr) of 1.9 and losses (tan δ ) of 0.025. For 3.8 GHz resonance, the antenna has size of 29.5 mm x 38 mm on a ground plane of 50 mm x 60 mm. Measurements of the final design are in excellent agreement with simulations. Moreover, measurements of the patch antenna on the proposed substrate (cellulose filter paper) collected at different bending radii and folding angles demonstrate performance consistency.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"177 1","pages":"41-47"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88048370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235105
M. M. Badawy, S. Zainud-Deen, H. Malhat
A polarization converter metamaterial surface (PCM) surface is designed for radar-cross-section reduction (RCSR) applications, through this paper. The presented PCM unit-cell composed of crescent shaped metallic patch. It introduces polarization conversion ratio (PCR) of 0.9 in the frequency-band from 8.2 GHz to 11.5 GHz. Different PCM surfaces arrangements uniform, triangle, and square structures are constructed and studied for more RCSR performance. The PCM square arrangement surface involves the rotation of the crescent unit cell with 90, 180 and 270 degrees to enhance the scattered waves cancellation and hence produce more RCSR. It introduces the optimum RCSR of 22.5 dB at 8.7 GHz for normal incident wave. The paper investigates the RCSR from different planar and conformal metallic surfaces loaded with PCM square arrangement. Different radii of surface curvature are investigated.
{"title":"Radar-Cross-Section Reduction Using Polarization Conversion Metasurface","authors":"M. M. Badawy, S. Zainud-Deen, H. Malhat","doi":"10.1109/NRSC49500.2020.9235105","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235105","url":null,"abstract":"A polarization converter metamaterial surface (PCM) surface is designed for radar-cross-section reduction (RCSR) applications, through this paper. The presented PCM unit-cell composed of crescent shaped metallic patch. It introduces polarization conversion ratio (PCR) of 0.9 in the frequency-band from 8.2 GHz to 11.5 GHz. Different PCM surfaces arrangements uniform, triangle, and square structures are constructed and studied for more RCSR performance. The PCM square arrangement surface involves the rotation of the crescent unit cell with 90, 180 and 270 degrees to enhance the scattered waves cancellation and hence produce more RCSR. It introduces the optimum RCSR of 22.5 dB at 8.7 GHz for normal incident wave. The paper investigates the RCSR from different planar and conformal metallic surfaces loaded with PCM square arrangement. Different radii of surface curvature are investigated.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"3 1","pages":"66-73"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82240073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/nrsc49500.2020.9235110
{"title":"[Front matter]","authors":"","doi":"10.1109/nrsc49500.2020.9235110","DOIUrl":"https://doi.org/10.1109/nrsc49500.2020.9235110","url":null,"abstract":"","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86519870","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235116
A. Shamim
Provides an abstract of the tutorial presentation and may include a brief professional biography of the presenter. The complete presentation was not made available for publication as part of the conference proceedings.
提供教程演示的摘要，可能包括演示者的简短专业简介。完整的报告没有作为会议记录的一部分提供出版。
{"title":"NRSC 2020 Tutorial","authors":"A. Shamim","doi":"10.1109/NRSC49500.2020.9235116","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235116","url":null,"abstract":"Provides an abstract of the tutorial presentation and may include a brief professional biography of the presenter. The complete presentation was not made available for publication as part of the conference proceedings.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"21 1","pages":"i-iii"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76944271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235099
B. Mohamed
Diabetic Retinopathy disease might lead to total loss of diabetic patient’s sight. In this research, we aim to detect the lesions of the Diabetic Retinopathy including Hemorrhage, and exudates. To be sure that the fundus images are in the same conditions of brightness, we applied Grey World approach on brightness channel then reconstruct the RGB. CLAHE and Unsharp filter are applied on reconstructed green channel and resulted in corrected green channel Gcor. The contrast stretching function is applied on the original green channel to result in stretched green channel Gs. The two images Gcor and Gs, are processed using thresholding and morphology operations to extract and localize optic disk, exudates, blood vessels, micro-aneurysm, Hemorrhage and macula. The color correction steps highlights Diabetic Retinopathy lesions. Sensitivity in our computer Diabetic Retinopathy diagnoses system achieved 94.44 % and outperforms most of current research works.
{"title":"Automatic Detection of Exudates and Hemorrhage in Fundus images","authors":"B. Mohamed","doi":"10.1109/NRSC49500.2020.9235099","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235099","url":null,"abstract":"Diabetic Retinopathy disease might lead to total loss of diabetic patient’s sight. In this research, we aim to detect the lesions of the Diabetic Retinopathy including Hemorrhage, and exudates. To be sure that the fundus images are in the same conditions of brightness, we applied Grey World approach on brightness channel then reconstruct the RGB. CLAHE and Unsharp filter are applied on reconstructed green channel and resulted in corrected green channel Gcor. The contrast stretching function is applied on the original green channel to result in stretched green channel Gs. The two images Gcor and Gs, are processed using thresholding and morphology operations to extract and localize optic disk, exudates, blood vessels, micro-aneurysm, Hemorrhage and macula. The color correction steps highlights Diabetic Retinopathy lesions. Sensitivity in our computer Diabetic Retinopathy diagnoses system achieved 94.44 % and outperforms most of current research works.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"12 1","pages":"277-284"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72984842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235091
Ahmed A. Sakr, A. Hussein, G. Fahmy, M. Abdelghany
There is an increasing research interest in digitizing the radio frequency (RF) signal directly after the antenna to obtain a flexible wireless software-defined radio (SDR). This is mainly because the next generations, 4G and 5G standards, are allocated different bands for the same standard due to the worsening shortage of the available spectrum. In this paper a high-speed two-stage dynamic CMOS-latched comparator is designed using 65 nm CMOS process. It achieves sampling frequency up to 10 GHz with resolution of 10.11 bits and 13.28 bits at 1 GHz sampling clock while keeping the propagation delay less than 64 psec. for 1 mV input voltage difference. The proposed design targets SDRs based on pulse-width modulation (PWM) and RF sampling analog-to-digital converters (ADCs).
{"title":"High-Speed Comparator Design for RF-to-Digital Receivers","authors":"Ahmed A. Sakr, A. Hussein, G. Fahmy, M. Abdelghany","doi":"10.1109/NRSC49500.2020.9235091","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235091","url":null,"abstract":"There is an increasing research interest in digitizing the radio frequency (RF) signal directly after the antenna to obtain a flexible wireless software-defined radio (SDR). This is mainly because the next generations, 4G and 5G standards, are allocated different bands for the same standard due to the worsening shortage of the available spectrum. In this paper a high-speed two-stage dynamic CMOS-latched comparator is designed using 65 nm CMOS process. It achieves sampling frequency up to 10 GHz with resolution of 10.11 bits and 13.28 bits at 1 GHz sampling clock while keeping the propagation delay less than 64 psec. for 1 mV input voltage difference. The proposed design targets SDRs based on pulse-width modulation (PWM) and RF sampling analog-to-digital converters (ADCs).","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"84 1","pages":"207-215"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83050325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235096
Mohamed S. Eleraky, Mohamed El Nozahi, E. Hegazi
This paper presents a low-power charge steering based frequency divider. This divider is designed for wireless local area networks (WLAN) and the internet of things (IoT) applications. A non-return to zero low power latch is proposed with charge steering logic (CSL) instead of the current source of the conventional current mode logic (CML). Then a master-slave flip flop is implemented using CSL latch. A divide by two circuits is proposed and designed using a 130-nm CMOS process. The frequency divider power consumption at 2.4 GHz, which is the most used frequency band in the WLAN application, is 36 μW from a 1.2-V supply. The sensitivity curve for the proposed divider is also presented. A maximum frequency of 9.6 GHz is achieved with a self-oscillation frequency of 1 GHz.
{"title":"A low power Charge Steering Based Frequency Divider","authors":"Mohamed S. Eleraky, Mohamed El Nozahi, E. Hegazi","doi":"10.1109/NRSC49500.2020.9235096","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235096","url":null,"abstract":"This paper presents a low-power charge steering based frequency divider. This divider is designed for wireless local area networks (WLAN) and the internet of things (IoT) applications. A non-return to zero low power latch is proposed with charge steering logic (CSL) instead of the current source of the conventional current mode logic (CML). Then a master-slave flip flop is implemented using CSL latch. A divide by two circuits is proposed and designed using a 130-nm CMOS process. The frequency divider power consumption at 2.4 GHz, which is the most used frequency band in the WLAN application, is 36 μW from a 1.2-V supply. The sensitivity curve for the proposed divider is also presented. A maximum frequency of 9.6 GHz is achieved with a self-oscillation frequency of 1 GHz.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"95 1","pages":"197-206"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80604728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-09-08DOI: 10.1109/NRSC49500.2020.9235092
H. Kotb, Y. Sabry, M. Abdallah, Marwan Sayed, H. Omran
We demonstrate a compact microelectromechanical systems based tunable single bandpass microwave photonic filter (MPF). A MEMS gold-platted micro-mirror facing cleaved optical fiber forms a tunable miniature Gires–Tournois interferometer (GTI). The micro-mirror was fabricated by Deep Reactive Ion Etching (DRIE) on silicon on insulator (SOI) wafer. A semiconductor optical amplifier (SOA) is employed simultaneously as a source of a broad optical spectrum and as an optical amplifier. A chirped-fiber Bragg grating is used as a dispersive delay line to provide a time delay to each wavelength slice. The simulation and experimental results are in good agreement showing a linear variation of the MPF center frequency with the separation between the micro-mirror and the fiber facet. The measured tuning range and tuning resolution are 1.3 to 2.5 GHz and 5.85 MHz/µm, respectively. The measured value of the stopband attenuation is more than 20 dB. The maximum value of the 3-dB bandwidth is 258 MHz.
我们展示了一种基于微机电系统的可调谐单带通微波光子滤波器(MPF)。利用微电子机械系统(MEMS)镀金微镜对劈裂光纤进行加工，形成可调谐的微型Gires-Tournois干涉仪(GTI)。采用深度反应离子刻蚀法(Deep Reactive Ion Etching, DRIE)在绝缘体硅片(SOI)上制备了微反射镜。半导体光放大器(SOA)同时用作宽光谱源和光放大器。啁啾光纤布拉格光栅用作色散延迟线，为每个波长片提供时间延迟。仿真结果与实验结果吻合较好，微反射镜中心频率随微反射镜与光纤面间距的增加呈线性变化。测量到的调谐范围和调谐分辨率分别为1.3 ~ 2.5 GHz和5.85 MHz/µm。阻带衰减的测量值大于20db。3db带宽最大值为258mhz。
{"title":"Tunable Microwave Single-Bandpass Photonic Filter Based on Amplified Mems-Based Gires–Tournois Interferometer","authors":"H. Kotb, Y. Sabry, M. Abdallah, Marwan Sayed, H. Omran","doi":"10.1109/NRSC49500.2020.9235092","DOIUrl":"https://doi.org/10.1109/NRSC49500.2020.9235092","url":null,"abstract":"We demonstrate a compact microelectromechanical systems based tunable single bandpass microwave photonic filter (MPF). A MEMS gold-platted micro-mirror facing cleaved optical fiber forms a tunable miniature Gires–Tournois interferometer (GTI). The micro-mirror was fabricated by Deep Reactive Ion Etching (DRIE) on silicon on insulator (SOI) wafer. A semiconductor optical amplifier (SOA) is employed simultaneously as a source of a broad optical spectrum and as an optical amplifier. A chirped-fiber Bragg grating is used as a dispersive delay line to provide a time delay to each wavelength slice. The simulation and experimental results are in good agreement showing a linear variation of the MPF center frequency with the separation between the micro-mirror and the fiber facet. The measured tuning range and tuning resolution are 1.3 to 2.5 GHz and 5.85 MHz/µm, respectively. The measured value of the stopband attenuation is more than 20 dB. The maximum value of the 3-dB bandwidth is 258 MHz.","PeriodicalId":6778,"journal":{"name":"2020 37th National Radio Science Conference (NRSC)","volume":"449 1","pages":"216-221"},"PeriodicalIF":0.0,"publicationDate":"2020-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82959132","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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