Pub Date : 2008-12-01DOI: 10.1109/RFM.2008.4897368
Ali K. Aswad, L. Abdulrazak, T. A. Rahman
New design of obtaining circular polarization (CP) radiation of a single-feed microstrip antenna is presented. The antenna substrate has an air-layer with thickness about 2.5% of the wavelength at a resonant operating frequency. By using a short probe pin the antenna can be excited easily. The two truncated opposite corners technique is used to obtain the circular polarized operation by selecting an optimal size of truncating. A flat ground plane with an optimal position for the probe pin is used to generate an impedance matching with a wide bandwidth. The CP patch antenna built for IEEE 802.11b/g (2.4 GHz ~ 2.4835 GHz) frequency bands. Measured -10 dB bandwidth is 14.3% and the measured S11, maximum gains and half-power beamwidth are, -41 dB, 8.3 dBi, 75deg respectively. The details of design and experimental results for the proposed design are presented and discussed.
{"title":"Design and development of high-gain wideband circularly polarized patch antenna","authors":"Ali K. Aswad, L. Abdulrazak, T. A. Rahman","doi":"10.1109/RFM.2008.4897368","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897368","url":null,"abstract":"New design of obtaining circular polarization (CP) radiation of a single-feed microstrip antenna is presented. The antenna substrate has an air-layer with thickness about 2.5% of the wavelength at a resonant operating frequency. By using a short probe pin the antenna can be excited easily. The two truncated opposite corners technique is used to obtain the circular polarized operation by selecting an optimal size of truncating. A flat ground plane with an optimal position for the probe pin is used to generate an impedance matching with a wide bandwidth. The CP patch antenna built for IEEE 802.11b/g (2.4 GHz ~ 2.4835 GHz) frequency bands. Measured -10 dB bandwidth is 14.3% and the measured S11, maximum gains and half-power beamwidth are, -41 dB, 8.3 dBi, 75deg respectively. The details of design and experimental results for the proposed design are presented and discussed.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"214 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132736505","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897472
M. Abdullah, W. Ali
This paper presents an overview of the performance of a dielectric lens that can be used in wireless broadband communication systems. Dielectric-lens is effective at generating highly shaped beams which enhance the wireless communication systems performance. Beam shaping is used to reduce multipath interference and to enhance gain, so that the received power level is compatible with the requirements of high-data-rate transmission. To investigate the gain, two dimensional Finite Difference Time Domain method (FDTD) was performed. The rods dielectrics are arranged in shape of semi circles and located in the physical domain to act as dielectric lens with permittivity constant 2. The result shows that when a plane wave propagates in free space and passing through rod dielectrics lens, the wave is reshaped and more concentrated.
{"title":"Numerical investigation of the effect of a rod dielectric lens on the electromagnetic wave strength using two dimensional FDTD method","authors":"M. Abdullah, W. Ali","doi":"10.1109/RFM.2008.4897472","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897472","url":null,"abstract":"This paper presents an overview of the performance of a dielectric lens that can be used in wireless broadband communication systems. Dielectric-lens is effective at generating highly shaped beams which enhance the wireless communication systems performance. Beam shaping is used to reduce multipath interference and to enhance gain, so that the received power level is compatible with the requirements of high-data-rate transmission. To investigate the gain, two dimensional Finite Difference Time Domain method (FDTD) was performed. The rods dielectrics are arranged in shape of semi circles and located in the physical domain to act as dielectric lens with permittivity constant 2. The result shows that when a plane wave propagates in free space and passing through rod dielectrics lens, the wave is reshaped and more concentrated.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133018970","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897443
O. Ayop, M. Rahim, T. Masri
This paper described the design of the dual band gap slotted patch EBG structure. By introducing double L slot into each EBG patch, a smaller rectangular patch has been introduced in each EBG patch resulting to the achievement of the second stop band frequency. The comparison between mushroom EBG structures has been investigated. The parametric study has been done involve the analysis of patch width effect of EBG and gap effects between elements in the EBG. The operating frequencies are 2.4 GHz ISM and 5.8 GHz UNI band. The slotted patch EBG structure and mushroom EBG structure have been simulated by using 3D simulation CST software. The design is based on FR4 board with has relative permittivity 4.7 and tangent loss 0.019.
{"title":"A dual band gap slotted patch electromagnetic band gap for dual band microstrip antenna","authors":"O. Ayop, M. Rahim, T. Masri","doi":"10.1109/RFM.2008.4897443","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897443","url":null,"abstract":"This paper described the design of the dual band gap slotted patch EBG structure. By introducing double L slot into each EBG patch, a smaller rectangular patch has been introduced in each EBG patch resulting to the achievement of the second stop band frequency. The comparison between mushroom EBG structures has been investigated. The parametric study has been done involve the analysis of patch width effect of EBG and gap effects between elements in the EBG. The operating frequencies are 2.4 GHz ISM and 5.8 GHz UNI band. The slotted patch EBG structure and mushroom EBG structure have been simulated by using 3D simulation CST software. The design is based on FR4 board with has relative permittivity 4.7 and tangent loss 0.019.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123678608","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897427
M. Arief, S. M. Idrus, S. Alifah
Subcarrier Multiplexing (SCM) is multiple radio frequency (RF) carrying signal to transmit through optical fiber using single wavelength. The most significant advantage of SCM in optical communications is its ability to place different optical carriers together closely. On the other hand, Wavelength Division Multiplexing (WDM) is a multiplexer at the transmitter to join the signals together, and a demultiplexer at the receiver to split them apart. In WDM each laser is modulated at a given speed, and the total aggregate capacity being transmitted along the high-bandwidth fiber is the sum total of the bit rates of the individual lasers. In this work, we investigate various issues in this scenario in order to provide a cost-effective, high performance solution for high speed data rates by the available bandwidth of the electrical and optical components. Therefore, SCM must be used in conjunction with WDM to utilize any significant fraction of the fiber bandwidth. The results is present higher bandwidth for long distance communication system (SMF, 150 km) by using SCM/WDM for Radio over Fiber. Therefore, the efficiency of bandwidth utilization of SCM is expected to be much better than conventional optical WDM.
{"title":"The SCM/WDM system model for radio over fiber communication link","authors":"M. Arief, S. M. Idrus, S. Alifah","doi":"10.1109/RFM.2008.4897427","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897427","url":null,"abstract":"Subcarrier Multiplexing (SCM) is multiple radio frequency (RF) carrying signal to transmit through optical fiber using single wavelength. The most significant advantage of SCM in optical communications is its ability to place different optical carriers together closely. On the other hand, Wavelength Division Multiplexing (WDM) is a multiplexer at the transmitter to join the signals together, and a demultiplexer at the receiver to split them apart. In WDM each laser is modulated at a given speed, and the total aggregate capacity being transmitted along the high-bandwidth fiber is the sum total of the bit rates of the individual lasers. In this work, we investigate various issues in this scenario in order to provide a cost-effective, high performance solution for high speed data rates by the available bandwidth of the electrical and optical components. Therefore, SCM must be used in conjunction with WDM to utilize any significant fraction of the fiber bandwidth. The results is present higher bandwidth for long distance communication system (SMF, 150 km) by using SCM/WDM for Radio over Fiber. Therefore, the efficiency of bandwidth utilization of SCM is expected to be much better than conventional optical WDM.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128002086","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897470
H.A. Rahman, S.N.M. Rameli, R. Kadir, Z. H. Murat, M. Taib
This technical paper investigates the correlation of body mass index (BMI) and human physical condition using resonant field imaging system (RFI).The results show the state of health level of students using physiological analysis. Frequency measurement is taken for 40 students including male and female students of electrical engineering around 8 am to 6 pm. The objective is to investigate the relationship of different health condition with different BMI category such as underweight, normal, overweight and obese. Based on the results presented, it is concluded that the samples with normal BMI are generally healthier. This shows that there is a clear and direct psychosomatic connection to the area of bioenergy. It also implies that pure and high frequency electrofield energy is projected from parts of the body.
{"title":"Analysis of correlation between BMI and human physical condition using resonant field imaging system (RFI)","authors":"H.A. Rahman, S.N.M. Rameli, R. Kadir, Z. H. Murat, M. Taib","doi":"10.1109/RFM.2008.4897470","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897470","url":null,"abstract":"This technical paper investigates the correlation of body mass index (BMI) and human physical condition using resonant field imaging system (RFI).The results show the state of health level of students using physiological analysis. Frequency measurement is taken for 40 students including male and female students of electrical engineering around 8 am to 6 pm. The objective is to investigate the relationship of different health condition with different BMI category such as underweight, normal, overweight and obese. Based on the results presented, it is concluded that the samples with normal BMI are generally healthier. This shows that there is a clear and direct psychosomatic connection to the area of bioenergy. It also implies that pure and high frequency electrofield energy is projected from parts of the body.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116988097","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897418
A. Abdipour, G. Moradi, S. Saboktakin
A white noise generator for VHF/UHF bands has been designed and implemented. The designed circuit employs the avalanche characteristics of a diode combined with wideband amplification. This noise generator has a relatively flat -30 dBm output power from 60 MHz to 1200 MHz. The comparison shows good agreement between results of the simulation and that of measurement. This noise generator can be used to test the noise temperature and noise figure of electronic devices and circuits.
{"title":"Design and implementation of a noise generator","authors":"A. Abdipour, G. Moradi, S. Saboktakin","doi":"10.1109/RFM.2008.4897418","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897418","url":null,"abstract":"A white noise generator for VHF/UHF bands has been designed and implemented. The designed circuit employs the avalanche characteristics of a diode combined with wideband amplification. This noise generator has a relatively flat -30 dBm output power from 60 MHz to 1200 MHz. The comparison shows good agreement between results of the simulation and that of measurement. This noise generator can be used to test the noise temperature and noise figure of electronic devices and circuits.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123266459","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897396
S. Sahrani, N. Semangin, S. Suhaili, D.A. Awg Mat, M. Osman,, M. Sawawi
Electromagnetic interference (EMI) due to radio frequency (RF) is known to cause interference in electronics devices. Interference may cause devices such as pacemaker to malfunctions with potentially adverse consequences. Exposure of electromagnetic interference comes from digital cellular telephones that are commonly used nowadays. This paper describes the preliminary case study on the effect of the EMI interference with a pacemaker. Temperatures were calculated at various frequencies to investigate the effect. Higher temperatures may cause discomfort to the patient.
{"title":"Electromagnetic interference on artificial heart pacemaker","authors":"S. Sahrani, N. Semangin, S. Suhaili, D.A. Awg Mat, M. Osman,, M. Sawawi","doi":"10.1109/RFM.2008.4897396","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897396","url":null,"abstract":"Electromagnetic interference (EMI) due to radio frequency (RF) is known to cause interference in electronics devices. Interference may cause devices such as pacemaker to malfunctions with potentially adverse consequences. Exposure of electromagnetic interference comes from digital cellular telephones that are commonly used nowadays. This paper describes the preliminary case study on the effect of the EMI interference with a pacemaker. Temperatures were calculated at various frequencies to investigate the effect. Higher temperatures may cause discomfort to the patient.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132458732","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897431
C. Y. Tan, K. Selvan
The design and simulation-based analysis of a 4-28 GHz double ridged conical horn is presented in this work. While the horn offers a VSWR of less than 1.6 over the entire bandwidth, it also exhibits desirable radiation patterns. More importantly, as per the simulation study, the ridged conical horn gives neat radiation and gain patterns throughout the band unlike the conventional ridged pyramidal horns whose patterns deteriorate at higher frequencies.
{"title":"Simulation study of a 4 – 28 GHz double ridged conical horn antenna","authors":"C. Y. Tan, K. Selvan","doi":"10.1109/RFM.2008.4897431","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897431","url":null,"abstract":"The design and simulation-based analysis of a 4-28 GHz double ridged conical horn is presented in this work. While the horn offers a VSWR of less than 1.6 over the entire bandwidth, it also exhibits desirable radiation patterns. More importantly, as per the simulation study, the ridged conical horn gives neat radiation and gain patterns throughout the band unlike the conventional ridged pyramidal horns whose patterns deteriorate at higher frequencies.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128478646","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897365
N. Aziz, I.A.J. Alias, A. T. Hashim, R. Mustafa, K. Anuar, S. Ahmad, W. Muhamad
The tissue culture laboratory provides the oil palm industry with innovations for the production of improved planting materials and information on the molecular biology of tissue culture processes. Research has shown that factors such as temperature, humidity, liquid, phase and gas compositions, are critical in producing quality clonal materials using tissue culture process. Therefore, it is necessary to provide good physical and chemical conditions for production of quality products. Consequently, sensors are required to monitor and record the data in growth room. All sensors will monitor critical parameters that focus on temperature, humidity, oxygen, carbon dioxide, ethylene and also an optical sensor for liquid phase and composition that will be linked to the database and analysis software for storing and analyzing the monitored data. The integrated sensors are low cost because it used local products and low power consumption and fabricated to suit the biological laboratory environment. The purpose of these integrated biotechnology sensors system is to serve as an interface among user, as the disturbance analysis program and an expert system in identifying the disturbance. The system would monitor via a smart RFID telemetry system and provide automatically email or short message (SMS) notifications upon identification of a disturbance module. Radio-frequency identification (RFID) is an automatic wireless identification method using radio waves, relying on storing and remotely retrieving data from integrated sensors using devices called RFID tags or transponders. Some tags can be read from several meters away and beyond the line of sight of the reader which make easier for data transportation. For the best communication path, active RFID tags will be equipped with autonomous networking; which greatly improves the utility of the device. Eventually, this smart RFID technology system could improve the efficiency of inventory tracking and management for oil palm tissue culture growth.
{"title":"Smart RFID system for oil palm bio-laboratory","authors":"N. Aziz, I.A.J. Alias, A. T. Hashim, R. Mustafa, K. Anuar, S. Ahmad, W. Muhamad","doi":"10.1109/RFM.2008.4897365","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897365","url":null,"abstract":"The tissue culture laboratory provides the oil palm industry with innovations for the production of improved planting materials and information on the molecular biology of tissue culture processes. Research has shown that factors such as temperature, humidity, liquid, phase and gas compositions, are critical in producing quality clonal materials using tissue culture process. Therefore, it is necessary to provide good physical and chemical conditions for production of quality products. Consequently, sensors are required to monitor and record the data in growth room. All sensors will monitor critical parameters that focus on temperature, humidity, oxygen, carbon dioxide, ethylene and also an optical sensor for liquid phase and composition that will be linked to the database and analysis software for storing and analyzing the monitored data. The integrated sensors are low cost because it used local products and low power consumption and fabricated to suit the biological laboratory environment. The purpose of these integrated biotechnology sensors system is to serve as an interface among user, as the disturbance analysis program and an expert system in identifying the disturbance. The system would monitor via a smart RFID telemetry system and provide automatically email or short message (SMS) notifications upon identification of a disturbance module. Radio-frequency identification (RFID) is an automatic wireless identification method using radio waves, relying on storing and remotely retrieving data from integrated sensors using devices called RFID tags or transponders. Some tags can be read from several meters away and beyond the line of sight of the reader which make easier for data transportation. For the best communication path, active RFID tags will be equipped with autonomous networking; which greatly improves the utility of the device. Eventually, this smart RFID technology system could improve the efficiency of inventory tracking and management for oil palm tissue culture growth.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126695984","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 : 2008-12-01DOI: 10.1109/RFM.2008.4897413
S. Mustam, M. Jenu
Controlling electromagnetic emissions level of high-speed digital circuit has become utmost important to ensure a proper operation and performance of electronic devices as well as electromagnetic compatibility (EMC) compliance. The increasing clock frequency of the digital circuits has created more challenges to the circuit designers in producing a system that is complying with regulation since its harmonic frequencies can contribute significant amount of electromagnetic emission. The paper will highlight the most effective technique to ensure proper mitigation approach to achieve EMC requirement. The measurements were conducted in Gigahertz Transverse Electromagnetic (GTEM) cell. It is interesting to indicate that, different method of emission reduction is only effective at certain range of frequency.
{"title":"Characterisations of electromagnetic emission of a high-speed digital circuit","authors":"S. Mustam, M. Jenu","doi":"10.1109/RFM.2008.4897413","DOIUrl":"https://doi.org/10.1109/RFM.2008.4897413","url":null,"abstract":"Controlling electromagnetic emissions level of high-speed digital circuit has become utmost important to ensure a proper operation and performance of electronic devices as well as electromagnetic compatibility (EMC) compliance. The increasing clock frequency of the digital circuits has created more challenges to the circuit designers in producing a system that is complying with regulation since its harmonic frequencies can contribute significant amount of electromagnetic emission. The paper will highlight the most effective technique to ensure proper mitigation approach to achieve EMC requirement. The measurements were conducted in Gigahertz Transverse Electromagnetic (GTEM) cell. It is interesting to indicate that, different method of emission reduction is only effective at certain range of frequency.","PeriodicalId":329128,"journal":{"name":"2008 IEEE International RF and Microwave Conference","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114709753","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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