Pub Date : 2012-12-01DOI: 10.1109/APMC.2012.6421575
S. Futatsumori, A. Kohmura, N. Yonemoto
The microwave shielding characteristics of quasi-isotropic carbon fiber reinforced plastics (CFRP) based on unidirectional (UD) materials are experimentally evaluated. First, fundamental characteristics of a UD CFRP laminate and a quasi-isotropic CFRP laminate are discussed. Second, shielding and polarization characteristics of a simple UD CFRP laminate are measured between 400 MHz and 6 GHz. The UD CFRP laminate, which has a same fiber direction, operates as a wire-grid and has more than 30 dB polarization ratio. Then, the dielectric constants of the fabricated CFRP laminate are measured by using the impedance analyzer. However, it was not suitable to describe whole wire-grid characteristics of the UD CFRP laminates. Finally, the measurement result of the quasi-isotropic CFRP laminate shows more than 40 dB shielding characteristics, which is almost the same as the dynamic range of the measurement system.
{"title":"Evaluation of microwave shielding characteristics of quasi-isotropic carbon fiber reinforced plastic laminates based on unidirectional materials","authors":"S. Futatsumori, A. Kohmura, N. Yonemoto","doi":"10.1109/APMC.2012.6421575","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421575","url":null,"abstract":"The microwave shielding characteristics of quasi-isotropic carbon fiber reinforced plastics (CFRP) based on unidirectional (UD) materials are experimentally evaluated. First, fundamental characteristics of a UD CFRP laminate and a quasi-isotropic CFRP laminate are discussed. Second, shielding and polarization characteristics of a simple UD CFRP laminate are measured between 400 MHz and 6 GHz. The UD CFRP laminate, which has a same fiber direction, operates as a wire-grid and has more than 30 dB polarization ratio. Then, the dielectric constants of the fabricated CFRP laminate are measured by using the impedance analyzer. However, it was not suitable to describe whole wire-grid characteristics of the UD CFRP laminates. Finally, the measurement result of the quasi-isotropic CFRP laminate shows more than 40 dB shielding characteristics, which is almost the same as the dynamic range of the measurement system.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132954841","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421788
Xin Yu
Power amplifiers(PAs) are nonlinear in nature and digital predistortion (DPD) often is used to compensate the nonlinearity of PAs. Generally, digital predistortion needs the bandwidth of feedforward and feedback signal several times higher than the transmission bandwidth to achieve reasonable good linearization performance. To reduce the bandwidth requirement on feedback signal path a novel approach, in which the coefficients would be approached step by step, is presented in this paper. Through optimizing the parameters the impact on linearization performance caused by feedback signal with incomplete spectral information can be significantly alleviate.
{"title":"Digital predistortion using feedback signal with incomplete spectral information","authors":"Xin Yu","doi":"10.1109/APMC.2012.6421788","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421788","url":null,"abstract":"Power amplifiers(PAs) are nonlinear in nature and digital predistortion (DPD) often is used to compensate the nonlinearity of PAs. Generally, digital predistortion needs the bandwidth of feedforward and feedback signal several times higher than the transmission bandwidth to achieve reasonable good linearization performance. To reduce the bandwidth requirement on feedback signal path a novel approach, in which the coefficients would be approached step by step, is presented in this paper. Through optimizing the parameters the impact on linearization performance caused by feedback signal with incomplete spectral information can be significantly alleviate.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133567844","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421863
Shohei Ishikawa, T. Ninomiya
In this paper, a planar polarization diversity antenna with low correlation coefficient and low mutual coupling is developed for wireless sensor network system at UHF region. A slit, to eliminate mutual coupling between two antennas, inserted on ground plane of conventional diversity antenna is straight; this fact causes a restriction to layout of a PCB board at UHF region. To save a large area for the electric component, we employ an L-shaped slit which has an advantage of compact and same performance as straight slit. The prototype of diversity antenna has been developed and measured. The measured result obtained the very low correlation coefficient of 0.021 and very low mutual coupling about -20 dB at 1 GHz in this work.
{"title":"Polarization diversity antenna with L-shaped slit for wireless sensor network","authors":"Shohei Ishikawa, T. Ninomiya","doi":"10.1109/APMC.2012.6421863","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421863","url":null,"abstract":"In this paper, a planar polarization diversity antenna with low correlation coefficient and low mutual coupling is developed for wireless sensor network system at UHF region. A slit, to eliminate mutual coupling between two antennas, inserted on ground plane of conventional diversity antenna is straight; this fact causes a restriction to layout of a PCB board at UHF region. To save a large area for the electric component, we employ an L-shaped slit which has an advantage of compact and same performance as straight slit. The prototype of diversity antenna has been developed and measured. The measured result obtained the very low correlation coefficient of 0.021 and very low mutual coupling about -20 dB at 1 GHz in this work.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133463379","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421868
Jong-Hyun Lee, In-sung Jeon, Young‐Ho Cho, Xu-Guang Wang, S. Yun
This paper presents a dual-band power divider using shunt open-stubs with enhanced attenuation characteristics. The improved transmission responses are achieved by transmission zeros created from shunt open-stubs, and the center frequencies of two passbands are also controlled by the shunt open-stubs. Moreover, the proposed power divider has control of bandwidths in two passbands. The bandwidths of two passbands are adjusted by the characteristic impedance and the electrical length of the admittance inverter between shunt open-stubs. To demonstrate the proposed method, a dualband power divider is designed at center frequencies of 3.2GHz with the fractional bandwidth (FBW) of 10% and 4.8GHz with the FBW of 7%, respectively.
{"title":"Design of dual-band power divider using shunt open-stubs with enhanced attenuation characteristics","authors":"Jong-Hyun Lee, In-sung Jeon, Young‐Ho Cho, Xu-Guang Wang, S. Yun","doi":"10.1109/APMC.2012.6421868","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421868","url":null,"abstract":"This paper presents a dual-band power divider using shunt open-stubs with enhanced attenuation characteristics. The improved transmission responses are achieved by transmission zeros created from shunt open-stubs, and the center frequencies of two passbands are also controlled by the shunt open-stubs. Moreover, the proposed power divider has control of bandwidths in two passbands. The bandwidths of two passbands are adjusted by the characteristic impedance and the electrical length of the admittance inverter between shunt open-stubs. To demonstrate the proposed method, a dualband power divider is designed at center frequencies of 3.2GHz with the fractional bandwidth (FBW) of 10% and 4.8GHz with the FBW of 7%, respectively.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115571388","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421548
S. Hung, Kai-Wen Cheng, Yeong-Her Wang
This paper presents a 28 GHz to 72 GHz isolation enhanced down-conversion broadband sub-harmonic mixer using the 0.15 μm GaAs pHEMT process with chip dimensions of 1.8 × 0.76 mm2. The configuration of the sub-harmonic mixer consists of one intermediate frequency (IF) amplifier, one compact band pass filter, and one Lange coupler utilizing an anti-parallel diode pair (APDP). To reduce line length and achieve broad operation bandwidth, the proposed grounded capacitor in the band pass filter can also enhance the local oscillation (LO)-radio frequency (RF) isolation of the sub-harmonic mixer. Both high conversion gain and isolation can be achieved between LO and RF-IF in the IF amplifier. The measured results indicate that the conversion gain of the mixer is 5.02 dB to 11.5 dB from RF frequency of 28 GHz to 72 GHz at the LO power of 9 dBm; the isolation of RF-IF, LO-IF, LO-RF, and 2LO-RF is 21 dB to 51.52 dB, 22.13 dB to 30.97 dB, 10.64 dB to 27.9 dB, and 48.9 dB to 72.35 dB, respectively.
本文提出了一种采用0.15 μm GaAs pHEMT工艺，芯片尺寸为1.8 × 0.76 mm2的28 GHz至72 GHz隔离增强下变频宽带次谐波混频器。亚谐波混频器的结构包括一个中频放大器、一个紧凑型带通滤波器和一个利用反并联二极管对(APDP)的兰格耦合器。为了减小线路长度和实现更宽的工作带宽，所提出的带通滤波器接地电容还可以增强次谐波混频器的本振(LO)-射频(RF)隔离。在中频放大器中，本LO和RF-IF之间可以实现高转换增益和隔离。测量结果表明，在本端功率为9 dBm时，该混频器在28ghz ~ 72ghz的射频范围内的转换增益为5.02 ~ 11.5 dB;RF-IF、LO-IF、LO-RF和2LO-RF的隔离度分别为21 dB ~ 51.52 dB、22.13 dB ~ 30.97 dB、10.64 dB ~ 27.9 dB和48.9 dB ~ 72.35 dB。
{"title":"Broadband sub-harmonic mixer with a compact band pass filter","authors":"S. Hung, Kai-Wen Cheng, Yeong-Her Wang","doi":"10.1109/APMC.2012.6421548","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421548","url":null,"abstract":"This paper presents a 28 GHz to 72 GHz isolation enhanced down-conversion broadband sub-harmonic mixer using the 0.15 μm GaAs pHEMT process with chip dimensions of 1.8 × 0.76 mm2. The configuration of the sub-harmonic mixer consists of one intermediate frequency (IF) amplifier, one compact band pass filter, and one Lange coupler utilizing an anti-parallel diode pair (APDP). To reduce line length and achieve broad operation bandwidth, the proposed grounded capacitor in the band pass filter can also enhance the local oscillation (LO)-radio frequency (RF) isolation of the sub-harmonic mixer. Both high conversion gain and isolation can be achieved between LO and RF-IF in the IF amplifier. The measured results indicate that the conversion gain of the mixer is 5.02 dB to 11.5 dB from RF frequency of 28 GHz to 72 GHz at the LO power of 9 dBm; the isolation of RF-IF, LO-IF, LO-RF, and 2LO-RF is 21 dB to 51.52 dB, 22.13 dB to 30.97 dB, 10.64 dB to 27.9 dB, and 48.9 dB to 72.35 dB, respectively.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114898494","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421501
N. Yang, Guoqiang Zhao, Zhuo Zhang, Houjun Sun, X. Lv
In this investigation, the design of instantaneous polarization radar system based on multilayer microtrip patch antenna is presented, and a convenient calibration method for instantaneous polarization radar system is introduced. According to the system structure, the distortion matrices R and T of receive and transmit channels including antenna and active circuits are derived. With the capabilities of instantaneous polarization measurement, the calibration method using three partly known, perfectly polarization-isolated calibrators is adopted. This method makes no assumption about the system distortion, and has no complicated calculations. Three measurements are sufficient for acquiring the distortion matrices R and T. Simulation results show the calibration performance.
{"title":"A convenient calibration method of instantaneous polarization radar system","authors":"N. Yang, Guoqiang Zhao, Zhuo Zhang, Houjun Sun, X. Lv","doi":"10.1109/APMC.2012.6421501","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421501","url":null,"abstract":"In this investigation, the design of instantaneous polarization radar system based on multilayer microtrip patch antenna is presented, and a convenient calibration method for instantaneous polarization radar system is introduced. According to the system structure, the distortion matrices R and T of receive and transmit channels including antenna and active circuits are derived. With the capabilities of instantaneous polarization measurement, the calibration method using three partly known, perfectly polarization-isolated calibrators is adopted. This method makes no assumption about the system distortion, and has no complicated calculations. Three measurements are sufficient for acquiring the distortion matrices R and T. Simulation results show the calibration performance.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114961204","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421866
Chia-Hung Mou, C. Tseng
In this paper, three sets of diamond-shape slot-coupled microstrip lines are integrated into a passive isolation component with the phase combination and cancellation properties for simultaneously transmitting and receiving applications. Since the slot-coupled microstrip can provide a wideband and accurate quadrature phase difference, the developed passive isolation component can effectively improve the isolation level and bandwidth between transmitting and receiving ports. The developed isolation component has a 30 dB isolation of 44.9 %.
{"title":"A new passive isolation component using slot-coupled microstrip lines for simultaneously transmitting and receiving applications","authors":"Chia-Hung Mou, C. Tseng","doi":"10.1109/APMC.2012.6421866","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421866","url":null,"abstract":"In this paper, three sets of diamond-shape slot-coupled microstrip lines are integrated into a passive isolation component with the phase combination and cancellation properties for simultaneously transmitting and receiving applications. Since the slot-coupled microstrip can provide a wideband and accurate quadrature phase difference, the developed passive isolation component can effectively improve the isolation level and bandwidth between transmitting and receiving ports. The developed isolation component has a 30 dB isolation of 44.9 %.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"309 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116327496","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421687
Cheng-Hsing Hsu, Chia-Hao Chang
This paper presents a novel design of a multilateral monopole antenna for ultra-wideband applications. It consists of a multilateral patch with a U-shaped notched, which intends to obtain frequency notched for WLAN. The proposed antenna operates from 2.65GHz to 11GHz for return loss of less than -10dB with 5.05-6 GHz notched. The notch frequency of the proposed antenna can be adjusted by controlling the location of slot. The measured results are in reasonably good agreement with the simulated results.
{"title":"Multilateral monopole antenna with a band-notched operation for UWB application","authors":"Cheng-Hsing Hsu, Chia-Hao Chang","doi":"10.1109/APMC.2012.6421687","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421687","url":null,"abstract":"This paper presents a novel design of a multilateral monopole antenna for ultra-wideband applications. It consists of a multilateral patch with a U-shaped notched, which intends to obtain frequency notched for WLAN. The proposed antenna operates from 2.65GHz to 11GHz for return loss of less than -10dB with 5.05-6 GHz notched. The notch frequency of the proposed antenna can be adjusted by controlling the location of slot. The measured results are in reasonably good agreement with the simulated results.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123599010","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421657
Da-jeong Eom, S. Kahng, Boram Lee, Chun-Sik Woo, Hosub Lee
In this paper, a new method is suggested to reduce the size of a wide-band power divider. It is made compact with the help of a novel Metamaterial wide-band power divider. The power divider has the Zeroth Order Resonant (ZOR) bandpass filter that is as small as approximately about λg/17. This power divider is clearly different from others in that the proposed design uses simple microstrip structured Composite Right and Left-Handed (CRLH) filters. The power divider is analyzed based on even- and odd- mode approach. The power divider is measured and compared with the prediction. Also, the size reduction effect is addressed.
{"title":"Wide-band power divider miniaturized by combining CRLH ZOR bandpass filters","authors":"Da-jeong Eom, S. Kahng, Boram Lee, Chun-Sik Woo, Hosub Lee","doi":"10.1109/APMC.2012.6421657","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421657","url":null,"abstract":"In this paper, a new method is suggested to reduce the size of a wide-band power divider. It is made compact with the help of a novel Metamaterial wide-band power divider. The power divider has the Zeroth Order Resonant (ZOR) bandpass filter that is as small as approximately about λg/17. This power divider is clearly different from others in that the proposed design uses simple microstrip structured Composite Right and Left-Handed (CRLH) filters. The power divider is analyzed based on even- and odd- mode approach. The power divider is measured and compared with the prediction. Also, the size reduction effect is addressed.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123609517","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 : 2012-12-01DOI: 10.1109/APMC.2012.6421730
T. Ishizaki, M. Yamada, R. Miyamoto, M. Yoneda
To develop a miniaturized LTCC bandpass filter, new resonator topology is proposed. A parallel sub-resonator and a series sub-resonator are connected in parallel to form a composite main-resonator. Parasitic components are positively incorporated in each sub-resonator, where the space is efficiently utilized in multiple ways. It is inspired from a CRLH-resonator with left-handed and right-handed components. The combination of sub-resonators makes the resonance frequency much lower, resulting in filter miniaturization. The resonator performance is analyzed. An experimental filter is fabricated with state-of-the-art LTCC technology. The simulated and the measured results show very good agreement. Thus, it is confirmed that the proposed filter is effective for filter miniaturization.
{"title":"Super miniaturized LTCC filter using novel composite resonators","authors":"T. Ishizaki, M. Yamada, R. Miyamoto, M. Yoneda","doi":"10.1109/APMC.2012.6421730","DOIUrl":"https://doi.org/10.1109/APMC.2012.6421730","url":null,"abstract":"To develop a miniaturized LTCC bandpass filter, new resonator topology is proposed. A parallel sub-resonator and a series sub-resonator are connected in parallel to form a composite main-resonator. Parasitic components are positively incorporated in each sub-resonator, where the space is efficiently utilized in multiple ways. It is inspired from a CRLH-resonator with left-handed and right-handed components. The combination of sub-resonators makes the resonance frequency much lower, resulting in filter miniaturization. The resonator performance is analyzed. An experimental filter is fabricated with state-of-the-art LTCC technology. The simulated and the measured results show very good agreement. Thus, it is confirmed that the proposed filter is effective for filter miniaturization.","PeriodicalId":359125,"journal":{"name":"2012 Asia Pacific Microwave Conference Proceedings","volume":"127 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122106917","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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