Pub Date : 2015-04-12DOI: 10.1109/EUCAP.2014.6902587
J. Nessel, Jacquelynne R. Morse, M. Zemba
Over the next several years, NASA plans to launch several earth science missions which are expected to achieve data throughputs of 5-40 terabits per day transmitted from low earth orbiting spacecraft to ground stations. The current S-band and X-band frequency allocations in use by NASA, however, are incapable of supporting the data rates required to meet this demand. As such, NASA is in the planning stages to upgrade its existing Near Earth Network (NEN) polar ground stations to support Ka-band (25.5-27 GHz) operations. Consequently, it becomes imperative that characterization of propagation effects at these NEN sites is conducted to determine expected system performance, particularly at low elevation angles (<; 10deg) where spacecraft signal acquisition typically occurs. Since May 2011, NASA Glenn Research Center has installed and operated a Ka-band radiometer at the NEN site located in Svalbard, Norway. The Ka-band radiometer monitors the water vapor line, as well as 6 frequencies around 26.5 GHz at multiple elevation angles: 45deg, 20deg, and 10deg. Two-year data collection results indicate comparable performance to previously characterized northern latitude sites in the United States, i.e., Fairbanks, Alaska. It is observed that cloud cover at the Svalbard site remains the dominant loss mechanism for Ka-band links, resulting in a margin requirement of 4.1 dB to maintain link availability of 99% at 10deg elevation.
{"title":"Results from two years of Ka-band propagation characterization at Svalbard, Norway","authors":"J. Nessel, Jacquelynne R. Morse, M. Zemba","doi":"10.1109/EUCAP.2014.6902587","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902587","url":null,"abstract":"Over the next several years, NASA plans to launch several earth science missions which are expected to achieve data throughputs of 5-40 terabits per day transmitted from low earth orbiting spacecraft to ground stations. The current S-band and X-band frequency allocations in use by NASA, however, are incapable of supporting the data rates required to meet this demand. As such, NASA is in the planning stages to upgrade its existing Near Earth Network (NEN) polar ground stations to support Ka-band (25.5-27 GHz) operations. Consequently, it becomes imperative that characterization of propagation effects at these NEN sites is conducted to determine expected system performance, particularly at low elevation angles (<; 10deg) where spacecraft signal acquisition typically occurs. Since May 2011, NASA Glenn Research Center has installed and operated a Ka-band radiometer at the NEN site located in Svalbard, Norway. The Ka-band radiometer monitors the water vapor line, as well as 6 frequencies around 26.5 GHz at multiple elevation angles: 45deg, 20deg, and 10deg. Two-year data collection results indicate comparable performance to previously characterized northern latitude sites in the United States, i.e., Fairbanks, Alaska. It is observed that cloud cover at the Svalbard site remains the dominant loss mechanism for Ka-band links, resulting in a margin requirement of 4.1 dB to maintain link availability of 99% at 10deg elevation.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"09 1","pages":"3511-3515"},"PeriodicalIF":0.0,"publicationDate":"2015-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86025871","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 : 2014-11-20DOI: 10.1109/DIPED.2014.6958334
S. I. H. Shah, S. Bashir, Syed Dildar Hussain Shah
In this paper a novel design for miniaturization of patch antenna is presented. The proposed design for the miniaturized wide band patch antenna consists of hybrid techniques of H-shaped slot on the patch and defected ground structure. Defected ground structure is formed by cutting a combination of U and L-shaped slots. Patch and the ground plane are shorted for the further size reduction. These practices increase the current distribution path accompanied by increase in electrical length of the antenna. To validate the design a reference patch antenna is designed and its performance is compared with the proposed antenna. The designed antenna is 86% smaller than the conventional patch antenna. The miniaturized antenna has gain in the range of 4dBi to 5dBi while impedance bandwidth is in the range of 105MHz to 1700MHz. This form of compact wide band antenna is appropriate for numerous wireless communication systems like cell phone, Laptop and Hyperlane.
{"title":"Compact multiband microstrip patch antenna using defected ground structure (DGS)","authors":"S. I. H. Shah, S. Bashir, Syed Dildar Hussain Shah","doi":"10.1109/DIPED.2014.6958334","DOIUrl":"https://doi.org/10.1109/DIPED.2014.6958334","url":null,"abstract":"In this paper a novel design for miniaturization of patch antenna is presented. The proposed design for the miniaturized wide band patch antenna consists of hybrid techniques of H-shaped slot on the patch and defected ground structure. Defected ground structure is formed by cutting a combination of U and L-shaped slots. Patch and the ground plane are shorted for the further size reduction. These practices increase the current distribution path accompanied by increase in electrical length of the antenna. To validate the design a reference patch antenna is designed and its performance is compared with the proposed antenna. The designed antenna is 86% smaller than the conventional patch antenna. The miniaturized antenna has gain in the range of 4dBi to 5dBi while impedance bandwidth is in the range of 105MHz to 1700MHz. This form of compact wide band antenna is appropriate for numerous wireless communication systems like cell phone, Laptop and Hyperlane.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"29 1","pages":"2367-2370"},"PeriodicalIF":0.0,"publicationDate":"2014-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74401541","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902355
R. Shavit, R. Joffe, E. Falek
In this paper, we present a multilayer flat lens antenna with effective zero index. It is made of a multilayer and periodic structure of printed elements to enhance a single patch element gain from 6 dBi to 19 dBi with radiation efficiency close to 85%. This high radiation efficiency enables to reduce the antenna aperture size. In the literature, the concept of a flat lens with zero index fed symmetrically by a balanced dipole operating at X band is described in [1]. In our study the feeding dipole was replaced by a patch backed by a ground plane and optimized at Ka band. An array of 2×2 patch elements with a flat lens on top was designed and optimized for radiation efficiency, gain and radiation pattern. In the presentation a comparison between measured and computed results will be shown.
{"title":"Planar printed Ka band antenna for satellite communication based on metamaterial technology","authors":"R. Shavit, R. Joffe, E. Falek","doi":"10.1109/EUCAP.2014.6902355","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902355","url":null,"abstract":"In this paper, we present a multilayer flat lens antenna with effective zero index. It is made of a multilayer and periodic structure of printed elements to enhance a single patch element gain from 6 dBi to 19 dBi with radiation efficiency close to 85%. This high radiation efficiency enables to reduce the antenna aperture size. In the literature, the concept of a flat lens with zero index fed symmetrically by a balanced dipole operating at X band is described in [1]. In our study the feeding dipole was replaced by a patch backed by a ground plane and optimized at Ka band. An array of 2×2 patch elements with a flat lens on top was designed and optimized for radiation efficiency, gain and radiation pattern. In the presentation a comparison between measured and computed results will be shown.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"27 1","pages":"2607-2609"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77703397","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902306
J. Moreno, I. González, M. J. Algar, F. Cátedra
The analysis of dielectric volumes by using the Moment Method is presented in this paper. The discretization with tetrahedrons or hexahedra are the most common techniques for analyzing dielectric volumes with this technique. The simplest methods for the mesh generation and the analysis work with flat elements (every faces of the tetrahedrons or hexahedra are planar), but meshes of high resolution are required to obtain accurate results. In this work, a mesh generator that generates body-fitted hexahedra is presented together an implementation of the Method of Moments that works with NURBS volumes for analyzing this kind of meshes efficiently. The combination of the two techniques allows studying dielectric volumes by using less dense meshes than the required with the planar ones. To validate both methods, different benchmark cases are summed up in the results section.
{"title":"Analysis of NURBS dielectric volumes by using the Method of Moments","authors":"J. Moreno, I. González, M. J. Algar, F. Cátedra","doi":"10.1109/EUCAP.2014.6902306","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902306","url":null,"abstract":"The analysis of dielectric volumes by using the Moment Method is presented in this paper. The discretization with tetrahedrons or hexahedra are the most common techniques for analyzing dielectric volumes with this technique. The simplest methods for the mesh generation and the analysis work with flat elements (every faces of the tetrahedrons or hexahedra are planar), but meshes of high resolution are required to obtain accurate results. In this work, a mesh generator that generates body-fitted hexahedra is presented together an implementation of the Method of Moments that works with NURBS volumes for analyzing this kind of meshes efficiently. The combination of the two techniques allows studying dielectric volumes by using less dense meshes than the required with the planar ones. To validate both methods, different benchmark cases are summed up in the results section.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"17 1","pages":"2418-2422"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73332847","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902006
L. Bråten, V. Arneson
The objective of this study is to obtain empirical experience with the expected signal degradation due to roadside trees for vehicular satellite communications at X-band. Broadband measurements of single tree attenuation were carried out at six locations at the campus of FFI, Kjeller, Norway. The excess vegetation attenuation was measured, utilising a network analyser, between 7.25 and 8 GHz during dry summer conditions. The species investigated were maple, spruce, lime, pine and birch. The elevation angle resembled typical elevation towards geostationary satellites. Reference measurements were performed besides the trees to calibrate the equipment, enabling extraction of the time, and frequency dependent attenuation variations. The signal component propagation through the trees was found to dominate the received power. The effect on attenuation from the main trunk obstructing the path was compared to measurement through branches only, and found to be significantly higher. The measured attenuation was compared with one existing model, showing a relatively large spread around predicted values. The attenuation (in dB) closely resembled a lognormal distribution. The observed attenuation values are expected to cause degraded communication quality during vegetation shadowing for vehicular satellite communication located close to trees.
{"title":"Measurements of single tree attenuation for vehicular satellite communications at X-band","authors":"L. Bråten, V. Arneson","doi":"10.1109/EUCAP.2014.6902006","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902006","url":null,"abstract":"The objective of this study is to obtain empirical experience with the expected signal degradation due to roadside trees for vehicular satellite communications at X-band. Broadband measurements of single tree attenuation were carried out at six locations at the campus of FFI, Kjeller, Norway. The excess vegetation attenuation was measured, utilising a network analyser, between 7.25 and 8 GHz during dry summer conditions. The species investigated were maple, spruce, lime, pine and birch. The elevation angle resembled typical elevation towards geostationary satellites. Reference measurements were performed besides the trees to calibrate the equipment, enabling extraction of the time, and frequency dependent attenuation variations. The signal component propagation through the trees was found to dominate the received power. The effect on attenuation from the main trunk obstructing the path was compared to measurement through branches only, and found to be significantly higher. The measured attenuation was compared with one existing model, showing a relatively large spread around predicted values. The attenuation (in dB) closely resembled a lognormal distribution. The observed attenuation values are expected to cause degraded communication quality during vegetation shadowing for vehicular satellite communication located close to trees.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"29 1","pages":"1264-1268"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82659732","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902605
D. Comite, A. Galli, E. Pettinelli, G. Valério
The detection capabilities of ground penetrating radar (GPR) for shallow subsurface investigations is primarily related to the efficient design of the antennas and to the suitable choice of the signal waveforms. An exploration of such aspects is the subject of the present work, with specific interest to ground-coupled monostatic and bistatic configurations. In order to address in a consistent way the issues related to the influence of the type of antennas and of the transmitted signal traces, extensive analyses have been performed numerically, based on ad-hoc implementation of a full-wave electromagnetic CAD tool. The relevant effects on the reconstruction of radar sections are evaluated and discussed in a number of test cases for the detection of buried scatterers in scenarios of practical interest.
{"title":"Numerical analysis of the detection performance of ground coupled radars for different antenna systems and signal features","authors":"D. Comite, A. Galli, E. Pettinelli, G. Valério","doi":"10.1109/EUCAP.2014.6902605","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902605","url":null,"abstract":"The detection capabilities of ground penetrating radar (GPR) for shallow subsurface investigations is primarily related to the efficient design of the antennas and to the suitable choice of the signal waveforms. An exploration of such aspects is the subject of the present work, with specific interest to ground-coupled monostatic and bistatic configurations. In order to address in a consistent way the issues related to the influence of the type of antennas and of the transmitted signal traces, extensive analyses have been performed numerically, based on ad-hoc implementation of a full-wave electromagnetic CAD tool. The relevant effects on the reconstruction of radar sections are evaluated and discussed in a number of test cases for the detection of buried scatterers in scenarios of practical interest.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"78 1","pages":"3584-3586"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88335051","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902263
R. Haupt
Time delay units are needed in large, wideband arrays that scan to angles far from boresight. The time delay consists of many different sizes of transmission line lengths that incrementally increase the signal path length. This paper shows the trade-offs between cost and performance in the placement of the time delay in a corporate feed.
{"title":"Tradeoffs in the placement of time delay in a large, wideband antenna array","authors":"R. Haupt","doi":"10.1109/EUCAP.2014.6902263","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902263","url":null,"abstract":"Time delay units are needed in large, wideband arrays that scan to angles far from boresight. The time delay consists of many different sizes of transmission line lengths that incrementally increase the signal path length. This paper shows the trade-offs between cost and performance in the placement of the time delay in a corporate feed.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"46 1","pages":"2259-2260"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90219389","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902321
T. Salmeron-Ruiz, M. Sierra-Castañer, F. Saccardi, S. Burgos, F. Cano-Fácila, L. Foged
A fast spherical near-field to far-field transformation using single cuts is introduced in this paper. It is based on calculating the Cylindrical Modal Coefficients of each individual near-field ring and processing them independently, considering them as cylinders of zero height and applying probe correction. The reconstruction of each far-field cut is obtained through an inverse Fast Fourier Transform. This procedure provides the opportunity to perform real time transformations due to its low acquisition and processing time. It is a useful tool for applications which do not require a full or accurate characterization, such as measuring the main patterns of an antenna or its most important parameters (peak gain, beam width, side lobe level, etc.).
{"title":"A fast single cut spherical near-field-to-far-field transformation using Cylindrical Modes","authors":"T. Salmeron-Ruiz, M. Sierra-Castañer, F. Saccardi, S. Burgos, F. Cano-Fácila, L. Foged","doi":"10.1109/EUCAP.2014.6902321","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902321","url":null,"abstract":"A fast spherical near-field to far-field transformation using single cuts is introduced in this paper. It is based on calculating the Cylindrical Modal Coefficients of each individual near-field ring and processing them independently, considering them as cylinders of zero height and applying probe correction. The reconstruction of each far-field cut is obtained through an inverse Fast Fourier Transform. This procedure provides the opportunity to perform real time transformations due to its low acquisition and processing time. It is a useful tool for applications which do not require a full or accurate characterization, such as measuring the main patterns of an antenna or its most important parameters (peak gain, beam width, side lobe level, etc.).","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"85 1","pages":"2476-2480"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90930515","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902358
S. Vaccaro, L. Diamond, D. Runyon, M. C. Viganó
Through a new approach to broadband satellite communications, ViaSat is launching a new era in satellite broadband with the innovative design of its high-capacity Ka-band satellite system, featuring the ViaSat-1 and ViaSat-2 satellites. ViaSat's new satellite architecture is transforming the performance of satellite communications and lifting the satellite industry to a more competitive position in telecommunications.
{"title":"Ka-band mobility terminals enabling new services","authors":"S. Vaccaro, L. Diamond, D. Runyon, M. C. Viganó","doi":"10.1109/EUCAP.2014.6902358","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902358","url":null,"abstract":"Through a new approach to broadband satellite communications, ViaSat is launching a new era in satellite broadband with the innovative design of its high-capacity Ka-band satellite system, featuring the ViaSat-1 and ViaSat-2 satellites. ViaSat's new satellite architecture is transforming the performance of satellite communications and lifting the satellite industry to a more competitive position in telecommunications.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"97 1","pages":"2617-2618"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77330707","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 : 2014-09-18DOI: 10.1109/EUCAP.2014.6902077
Mei Li, S. Xiao, Bingzhong Wang
A compact, low-profile, pattern-reconfigurable antenna utilizing high impedance surface (HIS) is proposed in this paper. The radiating element of the proposed antenna is closely spaced microstrip parasitic array. With proper design, the parasitic array excites surface wave propagation in HIS, which can be beneficial to obtain a broad and tilted beam generation. By adjusting the PIN diodes loaded in parasitic strips, two symmetrical steerable-beams are achieved. This antenna has great potential to be used as elements for wide-angle scanning applications. For verification, a novel 1×8 uniformly spaced linear array is designed and fabricated using the proposed pattern-reconfigurable antenna as elements. Measured results show that with uniform magnitudes and progressive phase excitation, the array performs a scan angle from -88° to +88° and a low side lobe level.
{"title":"Compact, low-profile, HIS-based pattern-reconfigurable antenna for wide-angle scanning","authors":"Mei Li, S. Xiao, Bingzhong Wang","doi":"10.1109/EUCAP.2014.6902077","DOIUrl":"https://doi.org/10.1109/EUCAP.2014.6902077","url":null,"abstract":"A compact, low-profile, pattern-reconfigurable antenna utilizing high impedance surface (HIS) is proposed in this paper. The radiating element of the proposed antenna is closely spaced microstrip parasitic array. With proper design, the parasitic array excites surface wave propagation in HIS, which can be beneficial to obtain a broad and tilted beam generation. By adjusting the PIN diodes loaded in parasitic strips, two symmetrical steerable-beams are achieved. This antenna has great potential to be used as elements for wide-angle scanning applications. For verification, a novel 1×8 uniformly spaced linear array is designed and fabricated using the proposed pattern-reconfigurable antenna as elements. Measured results show that with uniform magnitudes and progressive phase excitation, the array performs a scan angle from -88° to +88° and a low side lobe level.","PeriodicalId":22362,"journal":{"name":"The 8th European Conference on Antennas and Propagation (EuCAP 2014)","volume":"98 1","pages":"1541-1544"},"PeriodicalIF":0.0,"publicationDate":"2014-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74563811","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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