Pub Date : 2009-11-10DOI: 10.1109/IAS.2009.5325177
P. Villegas, J. Díaz, J. Martín-Ramos, Alberto Martín-Pernía, J. Esteban
One of the major drawbacks of high-ratio step-up transformers is the high value of their secondary-side capaci- tor. This value is reflected at the primary side, giving rise to a nondesirable one. There are some converters which include this capacitor in the topology and can cope with it, and even more, they need it. In particular, in high-voltage applications, we will find transformers with a large capacitance value since they use high-ratio step-up transformers. In this kind of applications, it is always interesting not to have inductors at the output filter, with single-capacitor filters being preferred instead. Thus, one of the simplest topologies is the parallel resonant converter (PRC) with a single-capacitor output filter. It can be controlled by the switching frequency and/or duty cycle, which makes zero voltage switching feasible in the power switches. In this paper, the PRC modeling and design and the experimental results are shown in a prototype delivering 3.5 kV and 260 W.
{"title":"A High- Voltage AC/DC Resonant Converter Based on PRC with Single Capacitor as an Output Filter","authors":"P. Villegas, J. Díaz, J. Martín-Ramos, Alberto Martín-Pernía, J. Esteban","doi":"10.1109/IAS.2009.5325177","DOIUrl":"https://doi.org/10.1109/IAS.2009.5325177","url":null,"abstract":"One of the major drawbacks of high-ratio step-up transformers is the high value of their secondary-side capaci- tor. This value is reflected at the primary side, giving rise to a nondesirable one. There are some converters which include this capacitor in the topology and can cope with it, and even more, they need it. In particular, in high-voltage applications, we will find transformers with a large capacitance value since they use high-ratio step-up transformers. In this kind of applications, it is always interesting not to have inductors at the output filter, with single-capacitor filters being preferred instead. Thus, one of the simplest topologies is the parallel resonant converter (PRC) with a single-capacitor output filter. It can be controlled by the switching frequency and/or duty cycle, which makes zero voltage switching feasible in the power switches. In this paper, the PRC modeling and design and the experimental results are shown in a prototype delivering 3.5 kV and 260 W.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123127028","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324881
R. A. Pinto, M. Cosetin, M. F. D. Silva, G. Denardin, A. Campos, R. N. Prado
This paper presents an efficient and compact emergency lighting system using high intensity light emitting diodes (LEDs). The proposal aims energy saving, high luminous efficacy and high useful life when replacing traditional emergency lighting systems and incandescent or compact fluorescent lamps by LEDs without any change in electrical system installation. A Buck converter is used to supply the LEDs and charge the battery by mains, with universal input voltage (90 VAC - 240 VAC), and a Boost converter is used to supply the LEDs by battery. The converters operate at high frequency and control the LEDs current independently. A Li-Ion battery was chosen because it has higher voltage and density of energy than Ni-MH one. The design attends the Brazilian standard (NBR 10898) and IEEE standard (IEEE Std 446-1995) for emergency lighting systems. The complete circuit was implemented and the experimental results show a satisfactory behavior of the lamp.
{"title":"LED Lamp with a Compact Emergency Lighting System","authors":"R. A. Pinto, M. Cosetin, M. F. D. Silva, G. Denardin, A. Campos, R. N. Prado","doi":"10.1109/IAS.2009.5324881","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324881","url":null,"abstract":"This paper presents an efficient and compact emergency lighting system using high intensity light emitting diodes (LEDs). The proposal aims energy saving, high luminous efficacy and high useful life when replacing traditional emergency lighting systems and incandescent or compact fluorescent lamps by LEDs without any change in electrical system installation. A Buck converter is used to supply the LEDs and charge the battery by mains, with universal input voltage (90 VAC - 240 VAC), and a Boost converter is used to supply the LEDs by battery. The converters operate at high frequency and control the LEDs current independently. A Li-Ion battery was chosen because it has higher voltage and density of energy than Ni-MH one. The design attends the Brazilian standard (NBR 10898) and IEEE standard (IEEE Std 446-1995) for emergency lighting systems. The complete circuit was implemented and the experimental results show a satisfactory behavior of the lamp.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126776566","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324960
Alberto Fernández Villán, Rodrigo García Acevedo, E. Alvarez, A. M. Campos, D. García, R. Usamentiaga, Marco Jimenez Meana, J. Sánchez
A laser-stripe system for the automation of welding processes in heavy industries is presented. Conventional methods use human intervention. A new solution using only common usage computer components has been developed, offering at least the same quality of performance at a low price, making laser systems without human intervention attractive for cost sensitive applications in heavy industries. A new system that guarantees satisfactory tracking results even when the welding gap geometry varies strongly or is distorted by noise has been developed.
{"title":"Low Cost System for Weld Tracking Based on Artificial Vision","authors":"Alberto Fernández Villán, Rodrigo García Acevedo, E. Alvarez, A. M. Campos, D. García, R. Usamentiaga, Marco Jimenez Meana, J. Sánchez","doi":"10.1109/IAS.2009.5324960","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324960","url":null,"abstract":"A laser-stripe system for the automation of welding processes in heavy industries is presented. Conventional methods use human intervention. A new solution using only common usage computer components has been developed, offering at least the same quality of performance at a low price, making laser systems without human intervention attractive for cost sensitive applications in heavy industries. A new system that guarantees satisfactory tracking results even when the welding gap geometry varies strongly or is distorted by noise has been developed.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122796790","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324800
G. Denardin, C. H. Barriquello, R. A. Pinto, M. F. D. Silva, A. Campos, R. N. Prado
One of the major challenges at the moment is the improvement of the present street lighting system. These systems are considered outdated due the lack of communication capabilities, not allowing system feedback. This work aims to add communication capabilities to the systems already in use, through the integration of a ZigBee™ compatible transceiver to the photoelectric relay used to turn the HPS lamps on/off. This change will turn each device into a node of a large wireless network across the city.
{"title":"An Intelligent System for Street Lighting Control and Measurement","authors":"G. Denardin, C. H. Barriquello, R. A. Pinto, M. F. D. Silva, A. Campos, R. N. Prado","doi":"10.1109/IAS.2009.5324800","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324800","url":null,"abstract":"One of the major challenges at the moment is the improvement of the present street lighting system. These systems are considered outdated due the lack of communication capabilities, not allowing system feedback. This work aims to add communication capabilities to the systems already in use, through the integration of a ZigBee™ compatible transceiver to the photoelectric relay used to turn the HPS lamps on/off. This change will turn each device into a node of a large wireless network across the city.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129169488","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324938
G. Mirzaeva, R. Betz, T. Summers
Due to their robustness and simplicity of control, dc machines continue to be widely used in many applications, including mining. Although a mature technology, dc machines still require research attention to accommodate for heavier loads and harder operation conditions dictated by production needs. Recent advances in sensoring, data acquisition, and signal processing technologies allow for direct measurement of quantities that used to be theoretically modeled or indirectly measured in the past. Within a research project with industry partners, the research team obtained the measurements of flux densities inside the motor air gap under both static and dynamic conditions. A variety of valuable information about the motor performance can be derived from these measurements. This paper focuses on one particular aspect of the commutation performance of dc machines, namely, the magnitudes and uniformity of current density through a brush, which, to a large degree, dictate the wear rates of the dc motor commutating group. This paper revisits the classical commutation theory, presents a mathematical model for current density estimation across a brush, and applies this model to the experimental results obtained. The results are then discussed and related to the commutation quality of the machine.
{"title":"Evaluation of Current Density in DC Motor Brushes for Mining Machines Based on Air Gap Field Measurement","authors":"G. Mirzaeva, R. Betz, T. Summers","doi":"10.1109/IAS.2009.5324938","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324938","url":null,"abstract":"Due to their robustness and simplicity of control, dc machines continue to be widely used in many applications, including mining. Although a mature technology, dc machines still require research attention to accommodate for heavier loads and harder operation conditions dictated by production needs. Recent advances in sensoring, data acquisition, and signal processing technologies allow for direct measurement of quantities that used to be theoretically modeled or indirectly measured in the past. Within a research project with industry partners, the research team obtained the measurements of flux densities inside the motor air gap under both static and dynamic conditions. A variety of valuable information about the motor performance can be derived from these measurements. This paper focuses on one particular aspect of the commutation performance of dc machines, namely, the magnitudes and uniformity of current density through a brush, which, to a large degree, dictate the wear rates of the dc motor commutating group. This paper revisits the classical commutation theory, presents a mathematical model for current density estimation across a brush, and applies this model to the experimental results obtained. The results are then discussed and related to the commutation quality of the machine.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"6 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120917422","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324832
Y. Ishikawa, K. Uehira, K. Yanaka
We propose the "Illumination Watermarking" technology with which the images of objects with no copyright protection can contain invisible digital watermarking, using spatially modulated illumination. This technology can be applied to objects without electronically embedded watermarking such as pictures painted by artists. We conducted experiments where one-bit binary data were embedded in one block that consisted of 8 x 8 pixels using the phase of the highest frequency component generated by DCT(Discrete Cosine Transform) and WHT(Walsh-Hadamard Transform). The experimental results revealed that embedded data could be read out with almost 100% accuracy in both cases.
我们提出了一种“照明水印”技术，利用空间调制的照明，在没有版权保护的物体的图像中包含不可见的数字水印。这项技术可以应用于没有电子嵌入水印的物体，比如艺术家画的画。我们进行了实验，其中使用DCT(离散余弦变换)和WHT(Walsh-Hadamard变换)生成的最高频率分量的相位，将一位二进制数据嵌入到一个由8 x 8像素组成的块中。实验结果表明，在这两种情况下，嵌入的数据都可以以几乎100%的准确率读出。
{"title":"Illumination Watermarking Technique Using Orthogonal Transforms","authors":"Y. Ishikawa, K. Uehira, K. Yanaka","doi":"10.1109/IAS.2009.5324832","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324832","url":null,"abstract":"We propose the \"Illumination Watermarking\" technology with which the images of objects with no copyright protection can contain invisible digital watermarking, using spatially modulated illumination. This technology can be applied to objects without electronically embedded watermarking such as pictures painted by artists. We conducted experiments where one-bit binary data were embedded in one block that consisted of 8 x 8 pixels using the phase of the highest frequency component generated by DCT(Discrete Cosine Transform) and WHT(Walsh-Hadamard Transform). The experimental results revealed that embedded data could be read out with almost 100% accuracy in both cases.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121404396","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324826
Liang Fang, Byeong-Hwa Lee, Jung-Pyo Hong, H. Nam
This paper describes an efficient approach for skillfully guiding the magnet reduction design in a single-phase line-start permanent magnet motor(LSPMM) without worsening motor torque and efficiency performances. The relevant decrease of magnet torque due to magnet reduction is compensated by improving the unique hybrid torque characteristic, that enhancing the balance ratio of reluctance torque to magnet torque. The increased reluctance toque also benefits to motor efficiency performance. Based on an existing LSPMM model, a simulation method, "torque-efficiency map" is proposed to estimate proper reduction of magnet according to assumed saliency ratio. Then, with estimated reduced amount of magnet, a flexible double-layer interior-PM(IPM) rotor structure is optimized with given torque and efficiency constrains. In this paper, the finite element analysis(FEA) combined with equivalent circuit method is used to calculate the LSPMM characteristics and performances. The validity of estimation of magnet reduction based on torque-efficiency map is verified by testing LSPMMs with reduced magnet usage.
{"title":"Estimation of Magnet Reduction in Single-Phase Line-Start Permanent Magnet Synchronous Motor","authors":"Liang Fang, Byeong-Hwa Lee, Jung-Pyo Hong, H. Nam","doi":"10.1109/IAS.2009.5324826","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324826","url":null,"abstract":"This paper describes an efficient approach for skillfully guiding the magnet reduction design in a single-phase line-start permanent magnet motor(LSPMM) without worsening motor torque and efficiency performances. The relevant decrease of magnet torque due to magnet reduction is compensated by improving the unique hybrid torque characteristic, that enhancing the balance ratio of reluctance torque to magnet torque. The increased reluctance toque also benefits to motor efficiency performance. Based on an existing LSPMM model, a simulation method, \"torque-efficiency map\" is proposed to estimate proper reduction of magnet according to assumed saliency ratio. Then, with estimated reduced amount of magnet, a flexible double-layer interior-PM(IPM) rotor structure is optimized with given torque and efficiency constrains. In this paper, the finite element analysis(FEA) combined with equivalent circuit method is used to calculate the LSPMM characteristics and performances. The validity of estimation of magnet reduction based on torque-efficiency map is verified by testing LSPMMs with reduced magnet usage.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116567356","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324797
W. Kaiser, R. P. Marques, A.F. Correa
Acoustic resonances are observed in high-pressure discharge lamps operated with ac input modulated power frequencies in the kilohertz range. This paper describes an optical resonance detection method for high-intensity discharge lamps using computer-controlled cameras and image processing software. Experimental results showing acoustic resonances in high-pressure sodium lamps are presented.
{"title":"An Alternative Optical Method for Acoustic Resonance Detection in HID Lamps","authors":"W. Kaiser, R. P. Marques, A.F. Correa","doi":"10.1109/IAS.2009.5324797","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324797","url":null,"abstract":"Acoustic resonances are observed in high-pressure discharge lamps operated with ac input modulated power frequencies in the kilohertz range. This paper describes an optical resonance detection method for high-intensity discharge lamps using computer-controlled cameras and image processing software. Experimental results showing acoustic resonances in high-pressure sodium lamps are presented.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"209 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127600841","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324899
Bing Sun, Xuemei Wang, Xiaomei Zhu, Masayuki Sato
In this investigation, a novel method with high voltage pulsed discharge directly in water was proposed to treat algae. It could produce multiple effects — shock waves, ultraviolet, hydroxyl radicals, strong electric field at the same time. In this article, the killing effects of different alga and two measurement methods were studied. The results showed that the inactivation ratio could reach 100%, and in selected species chlorophyta is the most difficult to treat, the diatom the second, and chrysophyte is the easiest. Platymonas spp is more difficult to treat than Chlorella. It also showed that there are no differences between the two measurement methods: the optical microscope and spectrophotometer. However, the spectrophotometer is much more efficient.
{"title":"Study of Eradicating Invasive Organisms from Ballast Water with Pulsed Discharge in Liquid","authors":"Bing Sun, Xuemei Wang, Xiaomei Zhu, Masayuki Sato","doi":"10.1109/IAS.2009.5324899","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324899","url":null,"abstract":"In this investigation, a novel method with high voltage pulsed discharge directly in water was proposed to treat algae. It could produce multiple effects — shock waves, ultraviolet, hydroxyl radicals, strong electric field at the same time. In this article, the killing effects of different alga and two measurement methods were studied. The results showed that the inactivation ratio could reach 100%, and in selected species chlorophyta is the most difficult to treat, the diatom the second, and chrysophyte is the easiest. Platymonas spp is more difficult to treat than Chlorella. It also showed that there are no differences between the two measurement methods: the optical microscope and spectrophotometer. However, the spectrophotometer is much more efficient.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126463734","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 : 2009-11-10DOI: 10.1109/IAS.2009.5324877
E. K. Sato, M. Kinoshita, Yushin Yamamoto, Tatsuaki Amboh
This paper presents a novel design for double-conversion uninterruptible power supply (UPS) systems that results in higher power density, higher efficiency, and more flexible parallelism for higher reliability. This design comprises a three-level circuit topology, a custom power semiconductor module, and a cross current sensorless parallel control. The innovative circuit topology results in a UPS with higher efficiency and dramatic size/weight reduction and confirms the advantages of three-level circuits in low-voltage applications. Higher reliability uninterruptible power system using parallel redundant UPS modules employs a novel cross current sensorless control without compromising the performance in comparison with single-module systems. Test results using single- and multiple-module systems confirm the improvement in efficiency and the high performance of this UPS. This novel design is hoped to contribute to greening information technology facilities by realizing high reliability and high efficiency at the same time.
{"title":"Redundant, High Density, High Efficiency Double Conversion Uninterruptible Power System","authors":"E. K. Sato, M. Kinoshita, Yushin Yamamoto, Tatsuaki Amboh","doi":"10.1109/IAS.2009.5324877","DOIUrl":"https://doi.org/10.1109/IAS.2009.5324877","url":null,"abstract":"This paper presents a novel design for double-conversion uninterruptible power supply (UPS) systems that results in higher power density, higher efficiency, and more flexible parallelism for higher reliability. This design comprises a three-level circuit topology, a custom power semiconductor module, and a cross current sensorless parallel control. The innovative circuit topology results in a UPS with higher efficiency and dramatic size/weight reduction and confirms the advantages of three-level circuits in low-voltage applications. Higher reliability uninterruptible power system using parallel redundant UPS modules employs a novel cross current sensorless control without compromising the performance in comparison with single-module systems. Test results using single- and multiple-module systems confirm the improvement in efficiency and the high performance of this UPS. This novel design is hoped to contribute to greening information technology facilities by realizing high reliability and high efficiency at the same time.","PeriodicalId":178685,"journal":{"name":"2009 IEEE Industry Applications Society Annual Meeting","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128110094","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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