Pub Date : 2005-05-09DOI: 10.1109/RADAR.2005.1435798
Yu Zhang, S. Qian, T. Thayaparan
Two new approaches for detecting a maneuvering air target in strong sea-clutter are proposed in this paper. One is based on the adaptive chirplet decomposition, and the other is inspired by the spectral subtraction. Experiments with real-world data samples show that both methods presented in this paper can effectively enhance the Doppler radar signals from maneuvering air targets though each has different strength and weakness.
{"title":"Two new approaches for detecting a maneuvering air target in strong sea-clutter","authors":"Yu Zhang, S. Qian, T. Thayaparan","doi":"10.1109/RADAR.2005.1435798","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435798","url":null,"abstract":"Two new approaches for detecting a maneuvering air target in strong sea-clutter are proposed in this paper. One is based on the adaptive chirplet decomposition, and the other is inspired by the spectral subtraction. Experiments with real-world data samples show that both methods presented in this paper can effectively enhance the Doppler radar signals from maneuvering air targets though each has different strength and weakness.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"33 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120891475","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435933
F. Kuroki, Y. Wagatsuma, T. Yoneyama
An FM-CW radar front-end was fabricated in an integrated manner at 60 GHz by using the NRD guide. Main emphasis was placed on compactness in size and high-precise operation in performance. The fabricated radar consists of an FM Gunn oscillator, a balanced mixer, and a planar antenna fed by leaky NRD guide with a mechanically beam-scanning performance. All circuit components and the antenna were contained in a compact housing of 170 /spl times/ 140 mm in area and 25 mm in thickness, and thus, a thin type of millimeter-wave radar front-end was successfully developed. And moreover, an error of distance estimation was measured to be less than a distance of 0.7 m.
{"title":"Mechanically beam-scanning NRD guide FM-CW radar for distance estimation at 60 GHz band","authors":"F. Kuroki, Y. Wagatsuma, T. Yoneyama","doi":"10.1109/RADAR.2005.1435933","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435933","url":null,"abstract":"An FM-CW radar front-end was fabricated in an integrated manner at 60 GHz by using the NRD guide. Main emphasis was placed on compactness in size and high-precise operation in performance. The fabricated radar consists of an FM Gunn oscillator, a balanced mixer, and a planar antenna fed by leaky NRD guide with a mechanically beam-scanning performance. All circuit components and the antenna were contained in a compact housing of 170 /spl times/ 140 mm in area and 25 mm in thickness, and thus, a thin type of millimeter-wave radar front-end was successfully developed. And moreover, an error of distance estimation was measured to be less than a distance of 0.7 m.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117206652","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435908
Wang Feng, Xiang Jiabin, Yang Jun
This paper proposes a method to generate simulation data of spaceborne MPC SAR from real airborne complex image SAR data. This method can be used for testing the theoretical analysis result of spaceborne MPC SAR.
{"title":"The method to inverse-simulate spaceborne MPC SAR data based on common airborne SAR data","authors":"Wang Feng, Xiang Jiabin, Yang Jun","doi":"10.1109/RADAR.2005.1435908","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435908","url":null,"abstract":"This paper proposes a method to generate simulation data of spaceborne MPC SAR from real airborne complex image SAR data. This method can be used for testing the theoretical analysis result of spaceborne MPC SAR.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130799191","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435904
H. C. Stankwitz, S. Taylor
Presented in this paper are selected new methods and applications of non-linear apodization for irregularly-shaped and sparse coherent apertures and arrays. The benefits include improved impulse response performance, i.e. reduced peak sidelobes and integrated sidelobe power, along with improved mainlobe resolution, compared to classic windowing techniques. Non-linear apodization (NLA) techniques can also serve as powerful engines for effective superresolution and bandwidth extrapolation of coherent data for filling sparse apertures. The sparse aperture filling property of superresolution algorithms for radar data forms the basis for a new concept which is introduced here: synthetic multiple aperture radar technology (SMART). Increased swath and/or reduced antenna size are some of the benefits postulated for SMART applied to synthetic aperture radar (SAR) systems. The benefits of these new methods and applications for nonlinear apodization are then demonstrated for two specific applications: 1) side lobe control for Y-type synthetic aperture radiometers, such as the European soil moisture and ocean salinity (SMOS) system [12] and JPL's proposed GeoSTAR [13] concept; and, 2) filling of sparse synthetic aperture radar data by exploiting the bandwidth extrapolation properties of non-linear apodization based superresolution techniques. The methods that have been developed and demonstrated here have potential application to a wide range of passive and e microwave remote sensing and radar systems.
{"title":"Advances in non-linear apodization for irregularly shaped and sparse two dimensional apertures","authors":"H. C. Stankwitz, S. Taylor","doi":"10.1109/RADAR.2005.1435904","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435904","url":null,"abstract":"Presented in this paper are selected new methods and applications of non-linear apodization for irregularly-shaped and sparse coherent apertures and arrays. The benefits include improved impulse response performance, i.e. reduced peak sidelobes and integrated sidelobe power, along with improved mainlobe resolution, compared to classic windowing techniques. Non-linear apodization (NLA) techniques can also serve as powerful engines for effective superresolution and bandwidth extrapolation of coherent data for filling sparse apertures. The sparse aperture filling property of superresolution algorithms for radar data forms the basis for a new concept which is introduced here: synthetic multiple aperture radar technology (SMART). Increased swath and/or reduced antenna size are some of the benefits postulated for SMART applied to synthetic aperture radar (SAR) systems. The benefits of these new methods and applications for nonlinear apodization are then demonstrated for two specific applications: 1) side lobe control for Y-type synthetic aperture radiometers, such as the European soil moisture and ocean salinity (SMOS) system [12] and JPL's proposed GeoSTAR [13] concept; and, 2) filling of sparse synthetic aperture radar data by exploiting the bandwidth extrapolation properties of non-linear apodization based superresolution techniques. The methods that have been developed and demonstrated here have potential application to a wide range of passive and e microwave remote sensing and radar systems.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"142 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114088945","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435932
D. Tan, Hongbo Sun, Yilong Lu
A passive radar is essentially a receiver-only radar that does not transmit signals; it only receives and thus operates independently without the direct synchronization from the non-cooperative illuminator. GSM base station transmitter as the illuminator of opportunity in a passive radar offers a covert means of uninterrupted surveillance where the major advantage is that the emitters of such transmissions are abundant. This paper presents an overview description of a low-cost experimental GSM based passive radar developed and implemented in Nanyang Technological University, Singapore. It describes the hardware architecture design and integration as well as the associated signal processing scheme of this experimental passive radar. Numerous field experiments were conducted with interesting results on sea and air moving target Doppler frequency detection and tracking presented to demonstrate and ascertain the performances and operating capabilities of the GSM based passive radar.
{"title":"Sea and air moving target measurements using a GSM based passive radar","authors":"D. Tan, Hongbo Sun, Yilong Lu","doi":"10.1109/RADAR.2005.1435932","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435932","url":null,"abstract":"A passive radar is essentially a receiver-only radar that does not transmit signals; it only receives and thus operates independently without the direct synchronization from the non-cooperative illuminator. GSM base station transmitter as the illuminator of opportunity in a passive radar offers a covert means of uninterrupted surveillance where the major advantage is that the emitters of such transmissions are abundant. This paper presents an overview description of a low-cost experimental GSM based passive radar developed and implemented in Nanyang Technological University, Singapore. It describes the hardware architecture design and integration as well as the associated signal processing scheme of this experimental passive radar. Numerous field experiments were conducted with interesting results on sea and air moving target Doppler frequency detection and tracking presented to demonstrate and ascertain the performances and operating capabilities of the GSM based passive radar.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114368549","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435914
Randy J. Jost, A. Uppuluri
This paper documents the continuation of the work that started with a student paper presented at Radar04. The earlier paper was a description of a graphic user interface (GUI) for SAR data processing that was developed for classroom use, based on a previously published algorithm. This GUI and associated MATLAB toolbox has now been extended to include several other capabilities and has grown into a toolkit that can be used in an introductory course in SAR image processing. Besides the processing of raw SAR data, the GUI and toolbox now include additional teaching and research capabilities, to include additional types of speckle filters and image compression capability. Apart from this the user can choose from two different algorithms that help to extract the single look image from the raw SAR data. These algorithms were implemented in MATLAB, because of its wide availability, and "self documenting" capability. Thus, the resulting package is suitable for classroom use to illustrate the principles of SAR data processing. Results of the project is made available to the radar community for use by the other schools and institutions that desire a simple SAR processing capability. The MATLAB code has been extensively commented, so that it provides useful baseline for other class projects. Although the material presented is not cutting edge research, it does provide a much-needed tutorial introduction to SAR processing in the classroom. We have also begun developing C and Python based versions of this package so that users can make comparative performance measurements and understand how various implementations of the algorithms affect the end results. We would like to acknowledge the help received from Alaska Satellite Facility (ASF) and the Space Dynamics Laboratory (SDL) at Utah State University for this project.
{"title":"MATLAB-based toolkit for an introductory course in SAR image processing","authors":"Randy J. Jost, A. Uppuluri","doi":"10.1109/RADAR.2005.1435914","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435914","url":null,"abstract":"This paper documents the continuation of the work that started with a student paper presented at Radar04. The earlier paper was a description of a graphic user interface (GUI) for SAR data processing that was developed for classroom use, based on a previously published algorithm. This GUI and associated MATLAB toolbox has now been extended to include several other capabilities and has grown into a toolkit that can be used in an introductory course in SAR image processing. Besides the processing of raw SAR data, the GUI and toolbox now include additional teaching and research capabilities, to include additional types of speckle filters and image compression capability. Apart from this the user can choose from two different algorithms that help to extract the single look image from the raw SAR data. These algorithms were implemented in MATLAB, because of its wide availability, and \"self documenting\" capability. Thus, the resulting package is suitable for classroom use to illustrate the principles of SAR data processing. Results of the project is made available to the radar community for use by the other schools and institutions that desire a simple SAR processing capability. The MATLAB code has been extensively commented, so that it provides useful baseline for other class projects. Although the material presented is not cutting edge research, it does provide a much-needed tutorial introduction to SAR processing in the classroom. We have also begun developing C and Python based versions of this package so that users can make comparative performance measurements and understand how various implementations of the algorithms affect the end results. We would like to acknowledge the help received from Alaska Satellite Facility (ASF) and the Space Dynamics Laboratory (SDL) at Utah State University for this project.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"25 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123051243","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435905
Ding Jianjiang, Yu Zhiqiang, Yan Da-zhi, R. Chongji
A practical parametric model (PPM), described the modulated characteristics for aircraft rotating structure in the air surveillance radars is presented and validated. Firstly, the scattering mechanism of the modulated signatures generated by aircraft rotating structure is described systematically based on the optical electromagnetism scattering theories. Secondly, the PPM is proposed based on some theoretical parametric models, the radar system and aircraft rotating structure. The relationships between the modulated signatures of the air surveillance radar echoes and the physical rotating structures of aircraft are analyzed. Thirdly, the PPM is validated by analysis of different conditions echoes including aircraft configuration and orientation, radar parameters and operation. The results demonstrate that the relatively unchangeable modulated feature, which is corresponding to the rotating structure of helicopters and propellers, can be described with the PPM, and can be reliably and steadily extracted from the echoes of the air surveillance radars.
{"title":"Modeling and validation of modulated characteristics for aircraft rotating structure in the air surveillance radars","authors":"Ding Jianjiang, Yu Zhiqiang, Yan Da-zhi, R. Chongji","doi":"10.1109/RADAR.2005.1435905","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435905","url":null,"abstract":"A practical parametric model (PPM), described the modulated characteristics for aircraft rotating structure in the air surveillance radars is presented and validated. Firstly, the scattering mechanism of the modulated signatures generated by aircraft rotating structure is described systematically based on the optical electromagnetism scattering theories. Secondly, the PPM is proposed based on some theoretical parametric models, the radar system and aircraft rotating structure. The relationships between the modulated signatures of the air surveillance radar echoes and the physical rotating structures of aircraft are analyzed. Thirdly, the PPM is validated by analysis of different conditions echoes including aircraft configuration and orientation, radar parameters and operation. The results demonstrate that the relatively unchangeable modulated feature, which is corresponding to the rotating structure of helicopters and propellers, can be described with the PPM, and can be reliably and steadily extracted from the echoes of the air surveillance radars.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"142 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129298325","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435967
H. Kamel, Wael Badawy
In this paper we apply a new smoothing Rao-Blackwellized particle filter to track a highly maneuverable target in a multiple-sensors network. The scenario of a highly-maneuverable target moving through a field of multiple sensors is addressed. The target is tracked through the sensors filed using both Rao-Blackwellized particle filter and the proposed smoothing filter. In a simulation comparison, the smoothing Rao-Blackwellized particle filter yields performance improvements when tracking a highly-maneuverable target.
{"title":"A smoothing Rao-Blackwellized particle filter for tracking a highly-maneuverable target","authors":"H. Kamel, Wael Badawy","doi":"10.1109/RADAR.2005.1435967","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435967","url":null,"abstract":"In this paper we apply a new smoothing Rao-Blackwellized particle filter to track a highly maneuverable target in a multiple-sensors network. The scenario of a highly-maneuverable target moving through a field of multiple sensors is addressed. The target is tracked through the sensors filed using both Rao-Blackwellized particle filter and the proposed smoothing filter. In a simulation comparison, the smoothing Rao-Blackwellized particle filter yields performance improvements when tracking a highly-maneuverable target.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129067463","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 : 2005-05-09DOI: 10.1109/MAES.2006.1581120
B. Cantrell, J. Rao, G. Tavik, M. Dorsey, V. Krichevsky
This paper presents a unique wideband array concept that includes a wideband array aperture incorporating radiating elements of different sizes and inter-element spacings. The array is a fully-filled aperture consisting of a core region surrounded by several layers of radiating elements which increase in size. By proper selection of the core region and the number of layers, one can form a beam with specified beamwidth over a five to one frequency range. The proposed concept considerably reduces the cost and complexity by decreasing the effective number of radiating elements and the corresponding receive or transmit modules. Numerical simulation results, ignoring the mutual coupling effects, are presented for array patterns at several frequencies to prove the concept. A possible beamforming concept is also included. Additional work is planned to prove the viability of the concept by taking the mutual coupling into account.
{"title":"Wideband array antenna concept","authors":"B. Cantrell, J. Rao, G. Tavik, M. Dorsey, V. Krichevsky","doi":"10.1109/MAES.2006.1581120","DOIUrl":"https://doi.org/10.1109/MAES.2006.1581120","url":null,"abstract":"This paper presents a unique wideband array concept that includes a wideband array aperture incorporating radiating elements of different sizes and inter-element spacings. The array is a fully-filled aperture consisting of a core region surrounded by several layers of radiating elements which increase in size. By proper selection of the core region and the number of layers, one can form a beam with specified beamwidth over a five to one frequency range. The proposed concept considerably reduces the cost and complexity by decreasing the effective number of radiating elements and the corresponding receive or transmit modules. Numerical simulation results, ignoring the mutual coupling effects, are presented for array patterns at several frequencies to prove the concept. A possible beamforming concept is also included. Additional work is planned to prove the viability of the concept by taking the mutual coupling into account.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114070651","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 : 2005-05-09DOI: 10.1109/RADAR.2005.1435937
B. Yazıcı, Margaret Cheney
This paper considers synthetic aperture radar and other synthetic aperture imaging systems from an arbitrary (known) flight path. We assume a single-scattering model for the radar data, and we assume that the ground topography is known but not necessarily flat. We focus on cases in which the antenna footprint is so large that the standard narrow-beam algorithms are not useful. For this case, (Nohan, CJ and Cheney, M, 2003) gave an explicit backprojection imaging formula that corrects for the ground topography, flight path, antenna beam pattern, source waveform, and other geometrical factors. In this paper, we show how to modify the backprojection algorithm to account for statistical information about noise and clutter.
本文研究了任意(已知)飞行路径下的合成孔径雷达和其他合成孔径成像系统。我们假设雷达数据的单散射模型，并且假设地面地形是已知的，但不一定是平坦的。我们关注的是天线占用空间太大以至于标准窄波束算法不起作用的情况。对于这种情况，(Nohan, CJ和Cheney, M, 2003)给出了一个明确的反向投影成像公式，该公式校正了地面地形、飞行路径、天线波束方向图、源波形和其他几何因素。在本文中，我们展示了如何修改反向投影算法来考虑噪声和杂波的统计信息。
{"title":"Synthetic aperture inversion for arbitrary flight paths in the presence of noise and clutter","authors":"B. Yazıcı, Margaret Cheney","doi":"10.1109/RADAR.2005.1435937","DOIUrl":"https://doi.org/10.1109/RADAR.2005.1435937","url":null,"abstract":"This paper considers synthetic aperture radar and other synthetic aperture imaging systems from an arbitrary (known) flight path. We assume a single-scattering model for the radar data, and we assume that the ground topography is known but not necessarily flat. We focus on cases in which the antenna footprint is so large that the standard narrow-beam algorithms are not useful. For this case, (Nohan, CJ and Cheney, M, 2003) gave an explicit backprojection imaging formula that corrects for the ground topography, flight path, antenna beam pattern, source waveform, and other geometrical factors. In this paper, we show how to modify the backprojection algorithm to account for statistical information about noise and clutter.","PeriodicalId":444253,"journal":{"name":"IEEE International Radar Conference, 2005.","volume":"169 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122503038","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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