Pub Date : 2003-10-14DOI: 10.1109/ISEMC.2003.1236726
D. Bellan, S. Pignari, P. Betti, D. Carillo, A. Gaggelli
This article reports the statistical analysis of an experimental procedure to monitor magnetic flux density (MFD) emissions on board of rolling stock. Measurements are operated in the time-domain and are aimed to track possibly modulated sinusoidal components of MFD emissions. The impact of additive internal noise (generated by the measurement equipment) as well as external noise (due to nonsinusoidal sources) is investigated. Since the final goal is safety assessment, the transformations experienced by the experimental data are analyzed and the statistics of a safety parameter (reported in the ICNIRP guidelines) is derived in closed form. Specifically, the expected value and variance of such a parameter are obtained analytically. Results' validity is checked on test signals with known statistical properties, by a repeated-run analysis.
{"title":"Impact of noise in the characterization of magnetic field radiated emissions","authors":"D. Bellan, S. Pignari, P. Betti, D. Carillo, A. Gaggelli","doi":"10.1109/ISEMC.2003.1236726","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236726","url":null,"abstract":"This article reports the statistical analysis of an experimental procedure to monitor magnetic flux density (MFD) emissions on board of rolling stock. Measurements are operated in the time-domain and are aimed to track possibly modulated sinusoidal components of MFD emissions. The impact of additive internal noise (generated by the measurement equipment) as well as external noise (due to nonsinusoidal sources) is investigated. Since the final goal is safety assessment, the transformations experienced by the experimental data are analyzed and the statistics of a safety parameter (reported in the ICNIRP guidelines) is derived in closed form. Specifically, the expected value and variance of such a parameter are obtained analytically. Results' validity is checked on test signals with known statistical properties, by a repeated-run analysis.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114794451","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236592
M. D'amore, E. Menghi, M. S. Sarto
The influence of the geometrical configuration of three single-core cable lines on the generated magnetic field is evaluated in the preliminary analysis. Numerical and experimental procedures are applied to estimate the performances of open or closed shields made of conductive or magnetic materials. A new high-voltage single-core "green cable" is proposed, in which the aluminum conductor is coiled by a double-layer shield realized with copper wires and a ferromagnetic sheath.
{"title":"Shielding techniques of the low-frequency magnetic field from cable power lines","authors":"M. D'amore, E. Menghi, M. S. Sarto","doi":"10.1109/ISEMC.2003.1236592","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236592","url":null,"abstract":"The influence of the geometrical configuration of three single-core cable lines on the generated magnetic field is evaluated in the preliminary analysis. Numerical and experimental procedures are applied to estimate the performances of open or closed shields made of conductive or magnetic materials. A new high-voltage single-core \"green cable\" is proposed, in which the aluminum conductor is coiled by a double-layer shield realized with copper wires and a ferromagnetic sheath.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114515806","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236578
R. Georgerian, M. Montrose
Microprocessors are designed with tens of thousands or millions of transistors that potentially can generate a significant amount of heat. Cooling of the package has become a challenge. Heat sinks are generally provided for the purpose of thermal dissipation, which helps keep components from becoming too hot. Destruction of the component may result. Designing heat sinks for optimal cooling within the constraints of size, space and airflow has become a challenge. In addition to being an efficient thermal radiator, a metal heat sink begins to appear as an efficient radiator of RF energy at higher operating frequencies. During normal operation or maintenance of a product, the heat sink may become exposed to users or service personnel. The temperature of the heat sink must be low enough as not to cause a burn injury if accidentally touched. Product safety standards require a label be affixed to the heat sink when a certain temperature level is exceeded, or if the heat sink is at voltage potential to prevent electric shock. In addition, the device must be kept cool enough as not to exceed the glass transition temperature (T/sub g/), or melting point of the printed wiring board material (PWB). Printed wiring boards, when exposed to high temperatures, may start to discolor, delaminate or even ignite causing serious safety consideration. To satisfy areas of concern related to heat sinks (heat dissipation and product safety while minimizing the propagation of RF energy), designers must maximize thermal cooling. To minimize the total amount of radiated emissions, the heat sink must be physically small based on the wavelength of the highest generated frequency internal to the component. Conversely, to maximize cooling, the heat sink must be physically large. The designer must be cognizant of all concerns, and select or design a heat sink that meets operational requirements.
{"title":"Product safety and the heat sink - dilemma of minimizing radiated emissions and maximizing thermal cooling","authors":"R. Georgerian, M. Montrose","doi":"10.1109/ISEMC.2003.1236578","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236578","url":null,"abstract":"Microprocessors are designed with tens of thousands or millions of transistors that potentially can generate a significant amount of heat. Cooling of the package has become a challenge. Heat sinks are generally provided for the purpose of thermal dissipation, which helps keep components from becoming too hot. Destruction of the component may result. Designing heat sinks for optimal cooling within the constraints of size, space and airflow has become a challenge. In addition to being an efficient thermal radiator, a metal heat sink begins to appear as an efficient radiator of RF energy at higher operating frequencies. During normal operation or maintenance of a product, the heat sink may become exposed to users or service personnel. The temperature of the heat sink must be low enough as not to cause a burn injury if accidentally touched. Product safety standards require a label be affixed to the heat sink when a certain temperature level is exceeded, or if the heat sink is at voltage potential to prevent electric shock. In addition, the device must be kept cool enough as not to exceed the glass transition temperature (T/sub g/), or melting point of the printed wiring board material (PWB). Printed wiring boards, when exposed to high temperatures, may start to discolor, delaminate or even ignite causing serious safety consideration. To satisfy areas of concern related to heat sinks (heat dissipation and product safety while minimizing the propagation of RF energy), designers must maximize thermal cooling. To minimize the total amount of radiated emissions, the heat sink must be physically small based on the wavelength of the highest generated frequency internal to the component. Conversely, to maximize cooling, the heat sink must be physically large. The designer must be cognizant of all concerns, and select or design a heat sink that meets operational requirements.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116895061","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236653
T. Tominaga, Y. Akiyama, H. Yamane, N. Kuwabara
A method of evaluating the isolation factor from an AC mains port to a telecommunication port was investigated. Telecommunication equipment was represented by a 4-port network consisting of a pair of wire and ground. The relationship between input and output signals of the network was represented by an F-matrix and the isolation factor (ratio of input to output signals) was derived from the matrix. We developed a method of measuring the parameters and the measured values for a resistance-network agree well with calculated ones. The evaluation results of the isolation factor for three types of telecommunication equipment show that isolation for differential-mode noise from AC mains to telecommunication ports is larger than that for common-mode noise.
{"title":"Investigation of electromagnetic noise transmission characteristics from AC mains port to telecommunication port","authors":"T. Tominaga, Y. Akiyama, H. Yamane, N. Kuwabara","doi":"10.1109/ISEMC.2003.1236653","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236653","url":null,"abstract":"A method of evaluating the isolation factor from an AC mains port to a telecommunication port was investigated. Telecommunication equipment was represented by a 4-port network consisting of a pair of wire and ground. The relationship between input and output signals of the network was represented by an F-matrix and the isolation factor (ratio of input to output signals) was derived from the matrix. We developed a method of measuring the parameters and the measured values for a resistance-network agree well with calculated ones. The evaluation results of the isolation factor for three types of telecommunication equipment show that isolation for differential-mode noise from AC mains to telecommunication ports is larger than that for common-mode noise.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123416629","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236687
A. Kitani, N. Kuwabara, F. Amemiya
Spherical dipole antenna has been used to evaluate EMC performance because it can consider small dipole source. In this paper, site attenuation of spherical dipole antenna is calculated using wire grid model. It is also measured in semi-anechoic chamber for 3m distance, and the result indicates the deviation between calculation and measurement result is within 4dB from 30 MHz to 1000 MHz. The site attenuation distribution is measured in a small semi-anechoic chamber and compared with the measured one. The result indicates that the large reflection loss absorber is effective to improve the performance of the site and the site attenuation is improved when transmitting and receiving antenna place at line unsymmetrical position.
{"title":"Analysis of site attenuation for spherical dipole antenna and its application","authors":"A. Kitani, N. Kuwabara, F. Amemiya","doi":"10.1109/ISEMC.2003.1236687","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236687","url":null,"abstract":"Spherical dipole antenna has been used to evaluate EMC performance because it can consider small dipole source. In this paper, site attenuation of spherical dipole antenna is calculated using wire grid model. It is also measured in semi-anechoic chamber for 3m distance, and the result indicates the deviation between calculation and measurement result is within 4dB from 30 MHz to 1000 MHz. The site attenuation distribution is measured in a small semi-anechoic chamber and compared with the measured one. The result indicates that the large reflection loss absorber is effective to improve the performance of the site and the site attenuation is improved when transmitting and receiving antenna place at line unsymmetrical position.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130030693","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236587
D. Friesen, S. Dobson
Internationally recognized accreditations of commercial EMC test houses are becoming a necessity. This is due to the normalization of test requirements worldwide through mutual recognition agreements and the adoption of common international standards. The ISO/IEC 17025 international standard sets out criteria used by accrediting bodies in assessing the laboratory's competency and ensuring the quality of measurement. Using practical experience, this submission provides direction and examples for test laboratories on how to implement some of the requirements set forth in ISO/IEC 17025. Not all activities detailed in the guide are covered. The primary scope of this presentation focuses on a quality system's influence on the technical aspects of a laboratory. The development of a corporate quality manual is the first step in implementing such a system. Quality records are maintained to ensure system compliance. Management's role in the implementation of this quality system begins as an expressed commitment to quality. The laboratory's scope of operation is determined and test methods are developed. Validations are performed to illustrate method compliance. Technical requirement of the quality system such as equipment selection, calibration and personnel training are detailed.
{"title":"Implementing an ISO/IEC 17025 quality system in a commercial EMC test laboratory environment","authors":"D. Friesen, S. Dobson","doi":"10.1109/ISEMC.2003.1236587","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236587","url":null,"abstract":"Internationally recognized accreditations of commercial EMC test houses are becoming a necessity. This is due to the normalization of test requirements worldwide through mutual recognition agreements and the adoption of common international standards. The ISO/IEC 17025 international standard sets out criteria used by accrediting bodies in assessing the laboratory's competency and ensuring the quality of measurement. Using practical experience, this submission provides direction and examples for test laboratories on how to implement some of the requirements set forth in ISO/IEC 17025. Not all activities detailed in the guide are covered. The primary scope of this presentation focuses on a quality system's influence on the technical aspects of a laboratory. The development of a corporate quality manual is the first step in implementing such a system. Quality records are maintained to ensure system compliance. Management's role in the implementation of this quality system begins as an expressed commitment to quality. The laboratory's scope of operation is determined and test methods are developed. Validations are performed to illustrate method compliance. Technical requirement of the quality system such as equipment selection, calibration and personnel training are detailed.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"74 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130514077","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236591
F. Garzia, A. Geri
The authors propose an optimization procedure based on genetic algorithms (GAs) able to aid the design of indoor MV/LV substations, reducing the magnetic field pollution outside the cabin. In particular, coupling GAs with a 3D magnetic field calculation code, an attempt was made to mitigate the magnetic field outside the transformer substation by an active shield, consisting of a simple energized loop. The proposed algorithm has been initially applied to study a simplified 2D configuration, in order to test the efficiency and the reliability of the code; then, it has been extended to achieve a fully 3D solution of the problem. From the analysis of the results, it emerges that the proposed approach may be advantageously used in order to mitigate the magnetic flux density in target volumes located near MV/LV cabins.
{"title":"Active shielding design in full 3D space of indoor MV/LV substations using genetic algorithm optimization","authors":"F. Garzia, A. Geri","doi":"10.1109/ISEMC.2003.1236591","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236591","url":null,"abstract":"The authors propose an optimization procedure based on genetic algorithms (GAs) able to aid the design of indoor MV/LV substations, reducing the magnetic field pollution outside the cabin. In particular, coupling GAs with a 3D magnetic field calculation code, an attempt was made to mitigate the magnetic field outside the transformer substation by an active shield, consisting of a simple energized loop. The proposed algorithm has been initially applied to study a simplified 2D configuration, in order to test the efficiency and the reliability of the code; then, it has been extended to achieve a fully 3D solution of the problem. From the analysis of the results, it emerges that the proposed approach may be advantageously used in order to mitigate the magnetic flux density in target volumes located near MV/LV cabins.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125568918","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236562
Hwang-Yoon Shim, Jiseong Kim, J. Yook
ESD and EMI problems and their possible solutions are addressed for the multi-layer power distribution network of high-speed digital systems. To prevent system from ESD damage, split I/O port ground with stitching element such as conductor or inductor is proposed, while stitching and decoupling capacitors are proved to be very effective for reducing electromagnetic radiation from the split power plane. Simulations based on 3D-finite difference time domain (FDTD) method are utilized for the analysis of practical high frequency multi-layered PC mainboard.
{"title":"Modeling of ESD and EMI problems in split multi-layer power distribution network","authors":"Hwang-Yoon Shim, Jiseong Kim, J. Yook","doi":"10.1109/ISEMC.2003.1236562","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236562","url":null,"abstract":"ESD and EMI problems and their possible solutions are addressed for the multi-layer power distribution network of high-speed digital systems. To prevent system from ESD damage, split I/O port ground with stitching element such as conductor or inductor is proposed, while stitching and decoupling capacitors are proved to be very effective for reducing electromagnetic radiation from the split power plane. Simulations based on 3D-finite difference time domain (FDTD) method are utilized for the analysis of practical high frequency multi-layered PC mainboard.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"184 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123008797","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236602
A. Schoof, T. Stadtler, J. ter Haseborg
In this work the near-field coupling of Bluetooth transmitters to a transmission line and a PCB loop is examined by high resolutional two dimensional simulations and measurements with different Bluetooth modules. Both simulations and measurements are compared, yielding good agreements in strength as well as in the topographic field-distribution.
{"title":"Two dimensional simulation and measurement of the coupling of Bluetooth signals into conductive structures","authors":"A. Schoof, T. Stadtler, J. ter Haseborg","doi":"10.1109/ISEMC.2003.1236602","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236602","url":null,"abstract":"In this work the near-field coupling of Bluetooth transmitters to a transmission line and a PCB loop is examined by high resolutional two dimensional simulations and measurements with different Bluetooth modules. Both simulations and measurements are compared, yielding good agreements in strength as well as in the topographic field-distribution.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126574091","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 : 2003-10-14DOI: 10.1109/ISEMC.2003.1236682
M. D'Urso, B. Audone
The most important parameter of any anechoic-shielded chamber used for radiated HIRF testing is field uniformity that can be achieved in the test zone when the System Under Test (SUT) is not present. One of the major difficulties is that it is almost impossible to avoid the presence of large metal structures, such as turntable and hoist, in test volume when large and heavy SUTs are tested. There are so many parameters that affect the degree of field uniformity that in most cases it is impossible to take all of them into account; however it is important to point out that anechoic material does not impact field uniformity to great extent. It becomes important to find out the right trade off among the most important test range parameters, which include (but are limited to): type and size of test antenna, its height above the chamber floor, its distance from the test volume, electric field polarization, size of the test volume and frequency range. The outcome of the simulation or experimental trial is binary (presence or absence of field uniformity) and therefore cannot be easily associated with a numerical scale. Logistic regressions, which is the right method to take into account that type of result, is the optimization tool proposed in this document to design the HIRF test range.
{"title":"The design of a facility to achieve the highest level of field uniformity in the test volume","authors":"M. D'Urso, B. Audone","doi":"10.1109/ISEMC.2003.1236682","DOIUrl":"https://doi.org/10.1109/ISEMC.2003.1236682","url":null,"abstract":"The most important parameter of any anechoic-shielded chamber used for radiated HIRF testing is field uniformity that can be achieved in the test zone when the System Under Test (SUT) is not present. One of the major difficulties is that it is almost impossible to avoid the presence of large metal structures, such as turntable and hoist, in test volume when large and heavy SUTs are tested. There are so many parameters that affect the degree of field uniformity that in most cases it is impossible to take all of them into account; however it is important to point out that anechoic material does not impact field uniformity to great extent. It becomes important to find out the right trade off among the most important test range parameters, which include (but are limited to): type and size of test antenna, its height above the chamber floor, its distance from the test volume, electric field polarization, size of the test volume and frequency range. The outcome of the simulation or experimental trial is binary (presence or absence of field uniformity) and therefore cannot be easily associated with a numerical scale. Logistic regressions, which is the right method to take into account that type of result, is the optimization tool proposed in this document to design the HIRF test range.","PeriodicalId":359422,"journal":{"name":"2003 IEEE Symposium on Electromagnetic Compatibility. Symposium Record (Cat. No.03CH37446)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116058332","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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