Pub Date : 2012-06-17DOI: 10.1109/MWSYM.2012.6257774
T. Shi, K. Li
A Solid-state oscillator design with Freescale LDDMOS devices is presented. The power booster technique of oscillator with two devices is presented as well. The single device oscillator can deliver up to 157W CW power at 2.45GHz with better than 43% efficiency and has a high-Q feedback ring which provides stable resonating frequency. The dual-devices oscillator can deliver 310W CW power at 2.4GHz with 46% efficiency. One of device in this dual-device oscillator operates as an oscillator and another one operates as a Class C amplifier. Both oscillators are housed in compact rooms including M&C circuits, a spatial advantage makes oscillator suitable for portable microwave ovens.
{"title":"High power Solid-state oscillator for microwave oven applications","authors":"T. Shi, K. Li","doi":"10.1109/MWSYM.2012.6257774","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6257774","url":null,"abstract":"A Solid-state oscillator design with Freescale LDDMOS devices is presented. The power booster technique of oscillator with two devices is presented as well. The single device oscillator can deliver up to 157W CW power at 2.45GHz with better than 43% efficiency and has a high-Q feedback ring which provides stable resonating frequency. The dual-devices oscillator can deliver 310W CW power at 2.4GHz with 46% efficiency. One of device in this dual-device oscillator operates as an oscillator and another one operates as a Class C amplifier. Both oscillators are housed in compact rooms including M&C circuits, a spatial advantage makes oscillator suitable for portable microwave ovens.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"104 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80481121","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6259536
E. Li, E. Liu
This paper systematically explores the underlying principle of a special domain and modal decomposition approach, and reports its latest advancement in modeling and simulation of multilayer packages and printed circuit boards for signal and power integrity analysis. Simulation results by different numerical techniques encompassed in the domain and modal decomposition approach are compared against those from measurement and full-wave simulation. The special domain and modal decomposition approach, compared with full-wave methods, exhibits faster simulation speed with good accuracy.
{"title":"Domain and modal decomposition for efficient signal and power integrity analysis of multilayer packages and PCBs","authors":"E. Li, E. Liu","doi":"10.1109/MWSYM.2012.6259536","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6259536","url":null,"abstract":"This paper systematically explores the underlying principle of a special domain and modal decomposition approach, and reports its latest advancement in modeling and simulation of multilayer packages and printed circuit boards for signal and power integrity analysis. Simulation results by different numerical techniques encompassed in the domain and modal decomposition approach are compared against those from measurement and full-wave simulation. The special domain and modal decomposition approach, compared with full-wave methods, exhibits faster simulation speed with good accuracy.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"19 4 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83284696","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6258284
A. Enayati, A. Tamminen, J. Ala-Laurinaho, A. Raisanen, G. Vandenbosch, W. De Raedt
A method has been introduced for the phase-retrieval step in the field of holographic imaging. In contrary to the phase-retrieval methods available in the literature which are mainly implemented in the wave-number domain the method introduced here retrieves the phase directly in the spatial domain. Although, the method is applicable to holographic imaging at any frequency and wavelength, its validity is investigated at 310 GHz practically. The image quality of a metallic object reconstructed by means of the method introduced confirms the validity and applicability of this method to holographic imaging systems.
{"title":"THz holographic imaging: A spatial-domain technique for phase retrieval and image reconstruction","authors":"A. Enayati, A. Tamminen, J. Ala-Laurinaho, A. Raisanen, G. Vandenbosch, W. De Raedt","doi":"10.1109/MWSYM.2012.6258284","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6258284","url":null,"abstract":"A method has been introduced for the phase-retrieval step in the field of holographic imaging. In contrary to the phase-retrieval methods available in the literature which are mainly implemented in the wave-number domain the method introduced here retrieves the phase directly in the spatial domain. Although, the method is applicable to holographic imaging at any frequency and wavelength, its validity is investigated at 310 GHz practically. The image quality of a metallic object reconstructed by means of the method introduced confirms the validity and applicability of this method to holographic imaging systems.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"41 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77747877","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6259468
P. Kangaslahti, B. Lim, T. Gaier, A. Tanner, M. Varonen, L. Samoska, Shannon T. Brown, B. Lambrigtsen, S. Reising, Jordan M. Tanabe, O. Montes, D. Dawson, C. Parashare
We currently achieve 3.4 dB noise figure at 183GHz and 2.1 dB noise figure at 90 GHz with our MMIC low noise amplifiers (LNAs) in room temperature. These amplifiers and the receivers we have built using them made it possible to conduct highly accurate airborne measurement campaigns from the Global Hawk unmanned aerial vehicle, develop millimeter wave internally calibrated radiometers for altimeter radar path delay correction, and build prototypes of large arrays of millimeter receivers for a geostationary interferometric sounder. We use the developed millimeter wave receivers to measure temperature and humidity profiles in the atmosphere and in hurricanes as well as to characterize the path delay error in ocean topography altimetry.
{"title":"Low noise amplifier receivers for millimeter wave atmospheric remote sensing","authors":"P. Kangaslahti, B. Lim, T. Gaier, A. Tanner, M. Varonen, L. Samoska, Shannon T. Brown, B. Lambrigtsen, S. Reising, Jordan M. Tanabe, O. Montes, D. Dawson, C. Parashare","doi":"10.1109/MWSYM.2012.6259468","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6259468","url":null,"abstract":"We currently achieve 3.4 dB noise figure at 183GHz and 2.1 dB noise figure at 90 GHz with our MMIC low noise amplifiers (LNAs) in room temperature. These amplifiers and the receivers we have built using them made it possible to conduct highly accurate airborne measurement campaigns from the Global Hawk unmanned aerial vehicle, develop millimeter wave internally calibrated radiometers for altimeter radar path delay correction, and build prototypes of large arrays of millimeter receivers for a geostationary interferometric sounder. We use the developed millimeter wave receivers to measure temperature and humidity profiles in the atmosphere and in hurricanes as well as to characterize the path delay error in ocean topography altimetry.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"35 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77734878","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6258397
A. Hamidipour, A. Fischer, L. Maurer, A. Stelzer
This paper investigates the feasibility of a gain enhancement technique using stacked directors for antennas in package. A 77-GHz antenna designed for automotive radar applications and a frequency multiplier were integrated in a 6×6mm2 embedded wafer level ball grid array (eWLB) package. The frequency multiplier generates the eighteenth harmonic of its input signal and allows the use of a commercial signal source to characterize the antenna. Parasitic directors were etched on a low-loss 2.54mm thick RT/duroid 5880 LZ laminate by means of photolithography and were mounted on the eWLB package. Theoretical analysis and full electromagnetic simulations were verified against the actual measurements of the antenna radiation beam pattern.
{"title":"On the feasibility of an antenna in package with stacked directors","authors":"A. Hamidipour, A. Fischer, L. Maurer, A. Stelzer","doi":"10.1109/MWSYM.2012.6258397","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6258397","url":null,"abstract":"This paper investigates the feasibility of a gain enhancement technique using stacked directors for antennas in package. A 77-GHz antenna designed for automotive radar applications and a frequency multiplier were integrated in a 6×6mm2 embedded wafer level ball grid array (eWLB) package. The frequency multiplier generates the eighteenth harmonic of its input signal and allows the use of a commercial signal source to characterize the antenna. Parasitic directors were etched on a low-loss 2.54mm thick RT/duroid 5880 LZ laminate by means of photolithography and were mounted on the eWLB package. Theoretical analysis and full electromagnetic simulations were verified against the actual measurements of the antenna radiation beam pattern.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"26 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82613583","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6258272
D. A. Calvillo-Cortes, K. Shi, M. de Langen, F. van Rijs, L. D. de Vreede
For wireless infrastructure applications, package-integrated power amplifiers are an appealing approach to achieve improved RF performance in terms of bandwidth and efficiency, as well as lower memory effects, form-factors and cost. This work discusses the specific design and implementation aspects for low-cost package-integrated PAs. Special attention is given to implementation deviations and tolerances when using bondwires. As case study, two class-E RF PA implementations with different bondwire-based output matching networks are evaluated for their predicted physics-based performance versus measured data. The high performance of these PAs shows the potential of these techniques for realizing ultra-compact next generation PA modules.
{"title":"On the design of package-integrated RF high-power amplifiers","authors":"D. A. Calvillo-Cortes, K. Shi, M. de Langen, F. van Rijs, L. D. de Vreede","doi":"10.1109/MWSYM.2012.6258272","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6258272","url":null,"abstract":"For wireless infrastructure applications, package-integrated power amplifiers are an appealing approach to achieve improved RF performance in terms of bandwidth and efficiency, as well as lower memory effects, form-factors and cost. This work discusses the specific design and implementation aspects for low-cost package-integrated PAs. Special attention is given to implementation deviations and tolerances when using bondwires. As case study, two class-E RF PA implementations with different bondwire-based output matching networks are evaluated for their predicted physics-based performance versus measured data. The high performance of these PAs shows the potential of these techniques for realizing ultra-compact next generation PA modules.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"16 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81131553","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6259490
Í. Molina-Fernández, A. Moscoso-Mártir, J. M. Ávila-Ruiz, R. Halir, P. Reyes-Iglesias, J. de-Oliva-Rubio, A. Ortega-Moñux
In this work some of the latest advances in multi-port technology in microwave and optical frequencies are reviewed. At microwaves frequencies, multilayer technologies are clearly improving the capabilities of six-port networks designs to cover wider frequency bands with minimum imbalances. This is making feasible new applications such as ultra-wideband phase shifter-less frequency discriminator. However, it is in the optical communications field where multi-port networks have become the preferred option for coherent receiver implementation. Recently, six-port based optical coherent receivers have started to be commercialized and there are promising studies that demonstrate how five-port networks can even enhance the performance of such receivers in the next generation of optical coherent receivers.
{"title":"Multi-port technology for microwave and optical communications","authors":"Í. Molina-Fernández, A. Moscoso-Mártir, J. M. Ávila-Ruiz, R. Halir, P. Reyes-Iglesias, J. de-Oliva-Rubio, A. Ortega-Moñux","doi":"10.1109/MWSYM.2012.6259490","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6259490","url":null,"abstract":"In this work some of the latest advances in multi-port technology in microwave and optical frequencies are reviewed. At microwaves frequencies, multilayer technologies are clearly improving the capabilities of six-port networks designs to cover wider frequency bands with minimum imbalances. This is making feasible new applications such as ultra-wideband phase shifter-less frequency discriminator. However, it is in the optical communications field where multi-port networks have become the preferred option for coherent receiver implementation. Recently, six-port based optical coherent receivers have started to be commercialized and there are promising studies that demonstrate how five-port networks can even enhance the performance of such receivers in the next generation of optical coherent receivers.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"1 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82733931","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6259548
G. Lasser, R. Langwieser, R. Dallinger, C. Mecklenbrauker
Reader systems for passive RFID tags suffer from a strong self generated interferer at the receiver, caused by transmitter to receiver leakage. This problem is often addressed by leaking carrier cancelers which compensate the leaking carrier at a single frequency. In this paper, we present measurements of the leakage channel in an RFID system. Based on the obtained results, we evaluate the leakage reduction that can be achieved by a novel analog broadband leakage canceller in the RF domain. Our proposed method allows for suppression of transmitter noise components. Moreover, it facilitates new broadband technologies, such as precision localisation or chipless RFID.
{"title":"Broadband leaking carrier cancellation for RFID systems","authors":"G. Lasser, R. Langwieser, R. Dallinger, C. Mecklenbrauker","doi":"10.1109/MWSYM.2012.6259548","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6259548","url":null,"abstract":"Reader systems for passive RFID tags suffer from a strong self generated interferer at the receiver, caused by transmitter to receiver leakage. This problem is often addressed by leaking carrier cancelers which compensate the leaking carrier at a single frequency. In this paper, we present measurements of the leakage channel in an RFID system. Based on the obtained results, we evaluate the leakage reduction that can be achieved by a novel analog broadband leakage canceller in the RF domain. Our proposed method allows for suppression of transmitter noise components. Moreover, it facilitates new broadband technologies, such as precision localisation or chipless RFID.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"10 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89748657","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6259774
N. Sarkar, M. Azizi, S. Fouladi, R. Mansour
We present the design and experimental results of a scanning microwave microscopy (SMM) system that does not require the use of a conventional atomic force microscope (AFM). Microfabricated SMM probes are actuated by integrated MEMS scanners in a commercially available multi-user process. This design is unique in the sense that the tip can be scanned over the sample both laterally and vertically, over a 10µm × 10µm scan range. We first validate our approach with a test-bench consisting of a fixed probe and an integrated sample-scanning stage. This device is used to obtain characteristic approach curves of S11 as a function of tip-sample separation. We then investigate the effect of tip-sample separation on the resolution of the instrument. CPW probes with integrated 1-D and 2-D actuation are then presented. These devices can be used to modulate the tip-sample separation to off-chip samples with a periodic (200Hz) signal, improving immunity to long-term system drifts. To increase measurement sensitivity, a single-stub matching network has been used to match high tip to sample impedance to the 50 ohm of a performance network analyzer. Measurement results agree very well with reported SMM measurements in the literature
我们提出了一个扫描微波显微镜(SMM)系统的设计和实验结果，不需要使用传统的原子力显微镜(AFM)。微加工的SMM探针是由集成的MEMS扫描仪在商业上可用的多用户过程中驱动的。这种设计的独特之处在于，尖端可以在10 μ m × 10 μ m的扫描范围内横向和纵向扫描样品。我们首先用一个由固定探针和集成样品扫描阶段组成的测试台验证我们的方法。该装置用于获得S11作为尖端样品分离函数的特征接近曲线。然后我们研究了尖端样品分离对仪器分辨率的影响。然后提出了集成一维和二维驱动的CPW探针。这些器件可用于调制具有周期性(200Hz)信号的尖端样品分离到片外样品，从而提高对长期系统漂移的免疫力。为了提高测量灵敏度，采用单根匹配网络将高尖端与样品阻抗匹配到性能网络分析仪的50欧姆。测量结果与文献中报道的SMM测量结果非常吻合
{"title":"Self-actuating scanning microwave microscopy probes","authors":"N. Sarkar, M. Azizi, S. Fouladi, R. Mansour","doi":"10.1109/MWSYM.2012.6259774","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6259774","url":null,"abstract":"We present the design and experimental results of a scanning microwave microscopy (SMM) system that does not require the use of a conventional atomic force microscope (AFM). Microfabricated SMM probes are actuated by integrated MEMS scanners in a commercially available multi-user process. This design is unique in the sense that the tip can be scanned over the sample both laterally and vertically, over a 10µm × 10µm scan range. We first validate our approach with a test-bench consisting of a fixed probe and an integrated sample-scanning stage. This device is used to obtain characteristic approach curves of S11 as a function of tip-sample separation. We then investigate the effect of tip-sample separation on the resolution of the instrument. CPW probes with integrated 1-D and 2-D actuation are then presented. These devices can be used to modulate the tip-sample separation to off-chip samples with a periodic (200Hz) signal, improving immunity to long-term system drifts. To increase measurement sensitivity, a single-stub matching network has been used to match high tip to sample impedance to the 50 ohm of a performance network analyzer. Measurement results agree very well with reported SMM measurements in the literature","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"84 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89843496","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 : 2012-06-17DOI: 10.1109/MWSYM.2012.6259757
M. Cabanes-Sempere, C. Cozzo, J. Catalá-Civera, F. Peñaranda-Foix, K. Ishizaki, S. Vaucher, M. Pouchon
Microwave Internal Gelation (MIG) is a chemical process proposed for the production of nuclear particle fuel. The reaction is triggered by a temperature increase by the means of microwave heating. Due to the short residence time of a solution droplet in the cavity a detailed knowledge of the interaction between microwaves and chemical solution (shaped in small drops) is required. This paper describes a new procedure that enables the measurement of dielectric properties of aqueous droplets that freely fall through a microwave cavity. These measurements provide the information to determine the optimal values of the parameters (such as frequency and power) that dictate the heating of a material under microwaves.
{"title":"Characterization of free falling drops inside a microwave cavity","authors":"M. Cabanes-Sempere, C. Cozzo, J. Catalá-Civera, F. Peñaranda-Foix, K. Ishizaki, S. Vaucher, M. Pouchon","doi":"10.1109/MWSYM.2012.6259757","DOIUrl":"https://doi.org/10.1109/MWSYM.2012.6259757","url":null,"abstract":"Microwave Internal Gelation (MIG) is a chemical process proposed for the production of nuclear particle fuel. The reaction is triggered by a temperature increase by the means of microwave heating. Due to the short residence time of a solution droplet in the cavity a detailed knowledge of the interaction between microwaves and chemical solution (shaped in small drops) is required. This paper describes a new procedure that enables the measurement of dielectric properties of aqueous droplets that freely fall through a microwave cavity. These measurements provide the information to determine the optimal values of the parameters (such as frequency and power) that dictate the heating of a material under microwaves.","PeriodicalId":6385,"journal":{"name":"2012 IEEE/MTT-S International Microwave Symposium Digest","volume":"28 1","pages":"1-3"},"PeriodicalIF":0.0,"publicationDate":"2012-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87603419","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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