Pub Date : 1900-01-01DOI: 10.1109/ICEMIC.1999.871641
J. Mclean, A. Medina, J. Sivaswamy, R. Sutton
Broadband, high-power baluns and matching transformers intended for application in EMC immunity testing are considered in detail. Emphasis is on baluns which are much greater than one-quarter wavelength long at the high end of their operating frequency range. A model for a helical Guanella 4:1 balun is developed and a helical Guanella design is presented. Experimental data which illuminates the action of parasitic modes is presented.
{"title":"Balun development for high-power, broadband EMC immunity test equipment","authors":"J. Mclean, A. Medina, J. Sivaswamy, R. Sutton","doi":"10.1109/ICEMIC.1999.871641","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871641","url":null,"abstract":"Broadband, high-power baluns and matching transformers intended for application in EMC immunity testing are considered in detail. Emphasis is on baluns which are much greater than one-quarter wavelength long at the high end of their operating frequency range. A model for a helical Guanella 4:1 balun is developed and a helical Guanella design is presented. Experimental data which illuminates the action of parasitic modes is presented.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"501 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125469319","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871587
R. Ganesan, S.K. Das, K.V.K. Sampath
HVDC technology deals with efficient transportation of hundreds of million watts of electrical power through conversion from ac to dc at the source end and dc to ac at the load end. Irrespective of system configuration, the converter generates a significant amount of power harmonics and feeds onto the transmission system. Systems of this kind couple unwanted electrical noise into co-located telephone circuits. This paper analyses the generation and coupling mechanism of power harmonics from HVDC to telecommunication systems and describes a case study involving underground telephone cables running parallel to HVDC transmission lines.
{"title":"HVDC transmission system performance from EMC perspective","authors":"R. Ganesan, S.K. Das, K.V.K. Sampath","doi":"10.1109/ICEMIC.1999.871587","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871587","url":null,"abstract":"HVDC technology deals with efficient transportation of hundreds of million watts of electrical power through conversion from ac to dc at the source end and dc to ac at the load end. Irrespective of system configuration, the converter generates a significant amount of power harmonics and feeds onto the transmission system. Systems of this kind couple unwanted electrical noise into co-located telephone circuits. This paper analyses the generation and coupling mechanism of power harmonics from HVDC to telecommunication systems and describes a case study involving underground telephone cables running parallel to HVDC transmission lines.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127945307","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871681
J. Behari
Low level electromagnetic fields have been found to produce a variety of biological effects, though the mechanism of such interactions is still not completely understood. The cell membrane of the brain is a critical structure perceiving the action of microwaves, which has received greater attention. The interactions of EM fields with living cells are considered for stochastic resonance, cooperative effects, non-equilibrium thermodynamic processes and nonlinear interactions. The nonlinear mechanism plays the main role in the process of transmembrane coupling of the signal to the cytoplasm. The criteria for safe exposure limits of an electromagnetic field to humans is also discussed.
{"title":"Biological effects and health implication of radiofrequency and microwave","authors":"J. Behari","doi":"10.1109/ICEMIC.1999.871681","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871681","url":null,"abstract":"Low level electromagnetic fields have been found to produce a variety of biological effects, though the mechanism of such interactions is still not completely understood. The cell membrane of the brain is a critical structure perceiving the action of microwaves, which has received greater attention. The interactions of EM fields with living cells are considered for stochastic resonance, cooperative effects, non-equilibrium thermodynamic processes and nonlinear interactions. The nonlinear mechanism plays the main role in the process of transmembrane coupling of the signal to the cytoplasm. The criteria for safe exposure limits of an electromagnetic field to humans is also discussed.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133613164","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871685
N. Jagannathan
Magnetic resonance imaging (MRI) is a widely used noninvasive imaging modality for obtaining diagnostic radiological images. An MRI scanner consists of several diverse technological components such as powerful static magnetic field, rapidly varying local gradient magnetic fields, pulsed radiofrequency (RF) field and liquid helium and/or liquid nitrogen. At present, there is no conclusive evidence for adverse biological effects in patients scanned by MRI. However, a clear knowledge and understanding of the various components are necessary and appropriate precautions should be adhered to, in order to ensure the safety of the patient as well as for the safe and smooth operation of the MR scanner.
{"title":"Magnetic resonance imaging (MRI): effects of electro-magnetic radiation and safety aspects","authors":"N. Jagannathan","doi":"10.1109/ICEMIC.1999.871685","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871685","url":null,"abstract":"Magnetic resonance imaging (MRI) is a widely used noninvasive imaging modality for obtaining diagnostic radiological images. An MRI scanner consists of several diverse technological components such as powerful static magnetic field, rapidly varying local gradient magnetic fields, pulsed radiofrequency (RF) field and liquid helium and/or liquid nitrogen. At present, there is no conclusive evidence for adverse biological effects in patients scanned by MRI. However, a clear knowledge and understanding of the various components are necessary and appropriate precautions should be adhered to, in order to ensure the safety of the patient as well as for the safe and smooth operation of the MR scanner.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132876251","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871630
D. Steinbach, M. Rehfeldt
The Open Area Test Site (OATS) method is the reference for measuring radiated RF-disturbances, according to the valid standards, even though there are numerous shortcomings inherent in this method. In practice, alternative methods in other measurement environments, such as the semi-anechoic chamber with conducting ground plane, free-space and GTEM-cell, have been applied with success. These procedures are applicable always when their measuring results correspond with the OATS measuring results. A great variety of reference measurement series are known from publications with which the correspondence of measuring results could be proved partially for certain equipment under test (EUT). In the paper, limits and possibilities of applying GTEM-cells are discussed in comparison with other methods. The data was gathered by using artificial EUTs for the entire frequency range. Contents and results of reference measurements are presented and discussed. The methods involved are scrutinised with their errors and uncertainty.
Open Area Test Site (OATS)方法是根据有效标准测量辐射射频干扰的参考方法，尽管该方法存在许多固有的缺点。在实践中，其他测量环境的替代方法，如带导电接平面的半消声室、自由空间和GTEM-cell，已经成功应用。当测量结果与OATS测量结果一致时，这些程序始终适用。从出版物中已知的各种参考测量系列，可以部分地证明某些被测设备(EUT)的测量结果的对应性。本文讨论了gtem细胞与其他方法的应用局限性和可能性。在整个频率范围内使用人工eut收集数据。介绍和讨论了参考测量的内容和结果。对所涉及的方法的误差和不确定性进行了仔细审查。
{"title":"A review on measurements techniques in OATS and GTEM cell","authors":"D. Steinbach, M. Rehfeldt","doi":"10.1109/ICEMIC.1999.871630","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871630","url":null,"abstract":"The Open Area Test Site (OATS) method is the reference for measuring radiated RF-disturbances, according to the valid standards, even though there are numerous shortcomings inherent in this method. In practice, alternative methods in other measurement environments, such as the semi-anechoic chamber with conducting ground plane, free-space and GTEM-cell, have been applied with success. These procedures are applicable always when their measuring results correspond with the OATS measuring results. A great variety of reference measurement series are known from publications with which the correspondence of measuring results could be proved partially for certain equipment under test (EUT). In the paper, limits and possibilities of applying GTEM-cells are discussed in comparison with other methods. The data was gathered by using artificial EUTs for the entire frequency range. Contents and results of reference measurements are presented and discussed. The methods involved are scrutinised with their errors and uncertainty.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128470187","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871658
R. Bera, A. K. Sen, P. Karmakar
The utilization of the Ka band (35 GHz) with a bandwidth of 2500 MHz seems to represent the largest significant achievement in LOS link application. The performance of a transceiver system in this band is determined largely by the ratio of wanted power to the unwanted power in the receiver. The unwanted power contributions are coming from two factors: (1) internal thermal noise generated by random atomic motions within the elements of the receiver and (2) the contribution in the sky noise temperature T/sub s/ due to EMI (electromagnetic interference) from rain drops. This extra term T/sub s/ has so far been ignored. Therefore, in view of propagation and noise study in the Ka band, both rain attenuation and receiver noise floor variations with rain are estimated over a tropical station, Calcutta, India. This is concluded with a special discussion of receiving systems utilising LNBCs (low noise block down converters) at the front end which are typically at 30 K or less where rain EMI effects are severe.
{"title":"Line of sight link degradation at millimeterwaves due to EMI from rain drops","authors":"R. Bera, A. K. Sen, P. Karmakar","doi":"10.1109/ICEMIC.1999.871658","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871658","url":null,"abstract":"The utilization of the Ka band (35 GHz) with a bandwidth of 2500 MHz seems to represent the largest significant achievement in LOS link application. The performance of a transceiver system in this band is determined largely by the ratio of wanted power to the unwanted power in the receiver. The unwanted power contributions are coming from two factors: (1) internal thermal noise generated by random atomic motions within the elements of the receiver and (2) the contribution in the sky noise temperature T/sub s/ due to EMI (electromagnetic interference) from rain drops. This extra term T/sub s/ has so far been ignored. Therefore, in view of propagation and noise study in the Ka band, both rain attenuation and receiver noise floor variations with rain are estimated over a tropical station, Calcutta, India. This is concluded with a special discussion of receiving systems utilising LNBCs (low noise block down converters) at the front end which are typically at 30 K or less where rain EMI effects are severe.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132137950","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871644
S. Ghosh, M.R. Singhley, S. Shastry, A. Chakrabarty
The Gigahertz Transverse Electromagnetic (GTEM) cell has been experimental and certified as a suitable test environment for radiated emission and susceptibility testing. In this paper the numerical technique applied for the fabrication of a typical GTEM cell has been explained. A method of moments based technique is applied to evaluate the charge distribution on the two conductors and the capacitance per unit length of the cell. The conductors are divided into large number of subsections. The charge density is assumed to be constant throughout a particular sub-section and concentrated at the center of a particular sub-section. This theory is further applied to design a GTEM cell with a characteristic impedance of 50 ohms. According to the size of the equipment under test (here the EUT is taken as a personal computer) the size of the cell is chosen. The cell is designed with appropriate low and high frequency terminations. The testing of the GTEM cell has been completed and the results are satisfactory.
{"title":"Design and characterisation of GTEM cell","authors":"S. Ghosh, M.R. Singhley, S. Shastry, A. Chakrabarty","doi":"10.1109/ICEMIC.1999.871644","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871644","url":null,"abstract":"The Gigahertz Transverse Electromagnetic (GTEM) cell has been experimental and certified as a suitable test environment for radiated emission and susceptibility testing. In this paper the numerical technique applied for the fabrication of a typical GTEM cell has been explained. A method of moments based technique is applied to evaluate the charge distribution on the two conductors and the capacitance per unit length of the cell. The conductors are divided into large number of subsections. The charge density is assumed to be constant throughout a particular sub-section and concentrated at the center of a particular sub-section. This theory is further applied to design a GTEM cell with a characteristic impedance of 50 ohms. According to the size of the equipment under test (here the EUT is taken as a personal computer) the size of the cell is chosen. The cell is designed with appropriate low and high frequency terminations. The testing of the GTEM cell has been completed and the results are satisfactory.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133176739","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871614
N. De, D. C. Pande, D. R. Poddar
A parallel plate dipole (PPD) sensor has been analysed using a direct three dimensional finite difference time domain (FDTD) method. The various electrical parameters of the PPD sensor derived using this method are: (a) the sensor response to a double exponential transient wave and a Gaussian pulse, (b) the sensor capacitance, (c) the equivalent length, (d) the equivalent volume, and (e) the figure of merit. The variations of these parameters with the structural dimension of the sensor are determined and compared with that obtained by the conventional electrostatic method. Finally the effect of a dielectric shell (used for the mechanical protection of the sensor) on the equivalent length and the response of the sensor are analysed and discussed.
{"title":"Analysis of parallel plate dipole sensor using finite difference time domain method","authors":"N. De, D. C. Pande, D. R. Poddar","doi":"10.1109/ICEMIC.1999.871614","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871614","url":null,"abstract":"A parallel plate dipole (PPD) sensor has been analysed using a direct three dimensional finite difference time domain (FDTD) method. The various electrical parameters of the PPD sensor derived using this method are: (a) the sensor response to a double exponential transient wave and a Gaussian pulse, (b) the sensor capacitance, (c) the equivalent length, (d) the equivalent volume, and (e) the figure of merit. The variations of these parameters with the structural dimension of the sensor are determined and compared with that obtained by the conventional electrostatic method. Finally the effect of a dielectric shell (used for the mechanical protection of the sensor) on the equivalent length and the response of the sensor are analysed and discussed.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122613709","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871659
D. C. Pande
Summary form only given, as follows. Personal wireless communication services are considered as a subset technology of the information age. They have gained importance and visibility over the 1990s, and future technological advancements in this field will be unprecedented. As the thrust into wireless personal communication continues with more advanced and compact technologies the risks increase of "corrupting" the information provided by such communication services because of various types of electromagnetic interference (EMI). To achieve electromagnetic compatibility (EMC) in mobile communication systems requires the right signal with sufficient strength for the customer. Such requirements bring a considerable number of issues, both intra- and inter-system EMI related problems for base stations and between ground stations and mobile units. In this paper we discuss only inter-system problems. The antenna design plays an important role in solving EMI problems of mobile communications systems, some of these design aspects are highlighted in this paper. A comprehensive study has been made for the EMI scenario resulting due to the diffraction scattering, path loss, reflection of paths, and multi-path interference in mobile communications. For prediction of the excessive interference level (EIL) various mathematical models for fading basics, Rayleigh fading, multi-path interference, Doppler spread basics, time delay spread basics, path loss, co-channel, and adjacent channel interference have been examined and analysed.
{"title":"Electromagnetic compatibility problems in mobile communication systems","authors":"D. C. Pande","doi":"10.1109/ICEMIC.1999.871659","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871659","url":null,"abstract":"Summary form only given, as follows. Personal wireless communication services are considered as a subset technology of the information age. They have gained importance and visibility over the 1990s, and future technological advancements in this field will be unprecedented. As the thrust into wireless personal communication continues with more advanced and compact technologies the risks increase of \"corrupting\" the information provided by such communication services because of various types of electromagnetic interference (EMI). To achieve electromagnetic compatibility (EMC) in mobile communication systems requires the right signal with sufficient strength for the customer. Such requirements bring a considerable number of issues, both intra- and inter-system EMI related problems for base stations and between ground stations and mobile units. In this paper we discuss only inter-system problems. The antenna design plays an important role in solving EMI problems of mobile communications systems, some of these design aspects are highlighted in this paper. A comprehensive study has been made for the EMI scenario resulting due to the diffraction scattering, path loss, reflection of paths, and multi-path interference in mobile communications. For prediction of the excessive interference level (EIL) various mathematical models for fading basics, Rayleigh fading, multi-path interference, Doppler spread basics, time delay spread basics, path loss, co-channel, and adjacent channel interference have been examined and analysed.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127885262","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 : 1900-01-01DOI: 10.1109/ICEMIC.1999.871596
P. Kulkarni, D. Rajeev
The design and construction of a modern warship offer a major challenge to an EMC engineer. By its very nature a warship is an extremely complex structure. It accommodates a multitude of complex electronic/electrical systems encased in a steel hull sitting on one of the best conducting media-water. To further complicate the situation these equipments are required to operate simultaneously. Being a mobile platform, a warship is required to operate in widely varying electromagnetic environments. As a result, the equipment fitted onboard is expected to operate satisfactorily and in a compatible manner in the most trying EM environment. To enable the sensitive equipment installed onboard a warship to operate in this ambience in a mutually compatible manner, it is necessary to provide shielding by housing them in specially designed and constructed shielded compartments. This paper deals with the various aspects to be considered in the design and construction of a shielded compartment onboard a warship. It also addresses the measures undertaken to ensure the maintenance of the designed EMC features throughout the lifecycle of a warship.
{"title":"Design considerations for shielded compartments in warships","authors":"P. Kulkarni, D. Rajeev","doi":"10.1109/ICEMIC.1999.871596","DOIUrl":"https://doi.org/10.1109/ICEMIC.1999.871596","url":null,"abstract":"The design and construction of a modern warship offer a major challenge to an EMC engineer. By its very nature a warship is an extremely complex structure. It accommodates a multitude of complex electronic/electrical systems encased in a steel hull sitting on one of the best conducting media-water. To further complicate the situation these equipments are required to operate simultaneously. Being a mobile platform, a warship is required to operate in widely varying electromagnetic environments. As a result, the equipment fitted onboard is expected to operate satisfactorily and in a compatible manner in the most trying EM environment. To enable the sensitive equipment installed onboard a warship to operate in this ambience in a mutually compatible manner, it is necessary to provide shielding by housing them in specially designed and constructed shielded compartments. This paper deals with the various aspects to be considered in the design and construction of a shielded compartment onboard a warship. It also addresses the measures undertaken to ensure the maintenance of the designed EMC features throughout the lifecycle of a warship.","PeriodicalId":104361,"journal":{"name":"Proceedings of the International Conference on Electromagnetic Interference and Compatibility","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127970979","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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