This paper describes the development of a new generation of single phase rectifier which is used to power telecommunications equipment. A rectifier is designed in such a manner to meets with all the requirements of the telecommunications industry. A number of common single phase topologies exist that could be realized as telecommunication power supplies, however, they do not completely satisfy all the industry requirements. This paper reviews recent progress in topology, control and design aspects in single phase PFC techniques. Different switching rectifier topologies are presented for various applications. Merits and limitations of these techniques are discussed. A detailed report of an investigation in the power converter system performance is also provided.
{"title":"AN OVERVIEW OF SINGLE PHASE TELECOMMUNICATION CONVERTER TOPOLOGIES: A COMPARATIVE STUDY","authors":"Gulam Amer, S. S. Rao","doi":"10.1234/MJEE.V4I3.253","DOIUrl":"https://doi.org/10.1234/MJEE.V4I3.253","url":null,"abstract":"This paper describes the development of a new generation of single phase rectifier which is used to power telecommunications equipment. A rectifier is designed in such a manner to meets with all the requirements of the telecommunications industry. A number of common single phase topologies exist that could be realized as telecommunication power supplies, however, they do not completely satisfy all the industry requirements. This paper reviews recent progress in topology, control and design aspects in single phase PFC techniques. Different switching rectifier topologies are presented for various applications. Merits and limitations of these techniques are discussed. A detailed report of an investigation in the power converter system performance is also provided.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"19-29"},"PeriodicalIF":0.0,"publicationDate":"2010-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66017108","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}
Nowadays using DG (distributed generation) in vast variety of cases has been more considerable due to its beneficial advantages, but interconnecting DG to radial distribution systems has some impact on the coordination of protection devices. The main point in the protection scheme is the diagnosis of fault locations, so producing a new method to identify fault location with high accuracy is necessary. This paper presents a novel approach to fault location identification with DG in distributed systems by the means of neural networks. According to this method using a distributed system as intentional islanding in necessary conditions is possible and reduces the ENS (Energy Not Supplied) of the net. Using separate NNs (neural networks) for each island (zone) will increase the accuracy of this method. Implementation results of this scheme on actual distributed systems has been simulated and reported.
{"title":"FAULT LOCATION SCHEME IN DISTRIBUTION SYSTEMS WITH DISTRIBUTED GENERATORS USING NEURAL NETWORKS","authors":"Shahgholian Ghazanfar, M. Rezaei","doi":"10.1234/MJEE.V4I2.333","DOIUrl":"https://doi.org/10.1234/MJEE.V4I2.333","url":null,"abstract":"Nowadays using DG (distributed generation) in vast variety of cases has been more considerable due to its beneficial advantages, but interconnecting DG to radial distribution systems has some impact on the coordination of protection devices. The main point in the protection scheme is the diagnosis of fault locations, so producing a new method to identify fault location with high accuracy is necessary. This paper presents a novel approach to fault location identification with DG in distributed systems by the means of neural networks. According to this method using a distributed system as intentional islanding in necessary conditions is possible and reduces the ENS (Energy Not Supplied) of the net. Using separate NNs (neural networks) for each island (zone) will increase the accuracy of this method. Implementation results of this scheme on actual distributed systems has been simulated and reported.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"57-62"},"PeriodicalIF":0.0,"publicationDate":"2010-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016983","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}
In this study we created an optimized Region Of Interest (ROI) based JPEG2000 image compression algorithm for mammograms compression. The first step was to perform the standard JPEG2000 algorithm. The second step was to optimize this algorithm in different aspects which are, the type of wavelet transform, the number of decomposition levels of this transform and the quantization table for mammograms compression. Also we tried not to damage the diagnostic information in the images and keep the Peak Signal to Noise Ratio value, high. We achieved high compression ratios up to 165:1 with PSNR=47.96dB which was significantly higher than the previous results studied. At the next step we modified the optimized image compression algorithm in order to compress the mammograms with one square-shaped ROI in a way that we could compress the ROI losslessly. Therefore we could obtain a high total compression ratio and meanwhile preserve the significant medical diagnostic information. In previous studies on ROIbased 8bpp mammograms compression, the highest total CR for the ROI size of 5% and 15% of the entire image, with lossless ROI compression, were 32:1 and 12:1 respectively these values have been raised up to 49.9:1 and 21.33:1 in this study.
{"title":"USING GENETIC ALGORITHM FOR OPTIMIZATION OF MAMMOGRAMS IMAGE COMPRESSION","authors":"Aynaz Besharat, E. Fatemizadeh","doi":"10.1234/MJEE.V4I3.222","DOIUrl":"https://doi.org/10.1234/MJEE.V4I3.222","url":null,"abstract":"In this study we created an optimized Region Of Interest (ROI) based JPEG2000 image compression algorithm for mammograms compression. The first step was to perform the standard JPEG2000 algorithm. The second step was to optimize this algorithm in different aspects which are, the type of wavelet transform, the number of decomposition levels of this transform and the quantization table for mammograms compression. Also we tried not to damage the diagnostic information in the images and keep the Peak Signal to Noise Ratio value, high. We achieved high compression ratios up to 165:1 with PSNR=47.96dB which was significantly higher than the previous results studied. At the next step we modified the optimized image compression algorithm in order to compress the mammograms with one square-shaped ROI in a way that we could compress the ROI losslessly. Therefore we could obtain a high total compression ratio and meanwhile preserve the significant medical diagnostic information. In previous studies on ROIbased 8bpp mammograms compression, the highest total CR for the ROI size of 5% and 15% of the entire image, with lossless ROI compression, were 32:1 and 12:1 respectively these values have been raised up to 49.9:1 and 21.33:1 in this study.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"7-18"},"PeriodicalIF":0.0,"publicationDate":"2010-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66017061","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}
In this paper, we propose a genetic fuzzy image filtering based on rank-ordered absolute differences (ROAD) and median of the absolute deviations from the median (MAD). The proposed method consists of three components, including fuzzy noise detection system, fuzzy switching scheme filtering, and fuzzy parameters optimization using genetic algorithms (GA) to perform efficient and effective noise removal. Our idea is to utilize MAD and ROAD as measures of noise probability of a pixel. Fuzzy inference system is used to justify the degree of which a pixel can be categorized as noisy. Based on the fuzzy inference result, the fuzzy switching scheme that adopts median filter as the main estimator is applied to the filtering. The GA training aims to find the best parameters for the fuzzy sets in the fuzzy noise detection. By the experimental results, the proposed method has successfully removed mixed impulse noise in low to medium probabilities, while keeping the uncorrupted pixels less affected by the median filtering. It also surpasses the other methods, either classical or soft computing-based approaches to impulse noise removal, in MAE and PSNR evaluations.
{"title":"Genetic Fuzzy Filter Based on MAD and ROAD to Remove Mixed Impulse Noise","authors":"N. Z. Janah, B. Baharudin","doi":"10.1234/MJEE.V4I2.283","DOIUrl":"https://doi.org/10.1234/MJEE.V4I2.283","url":null,"abstract":"In this paper, we propose a genetic fuzzy image filtering based on rank-ordered absolute differences (ROAD) and median of the absolute deviations from the median (MAD). The proposed method consists of three components, including fuzzy noise detection system, fuzzy switching scheme filtering, and fuzzy parameters optimization using genetic algorithms (GA) to perform efficient and effective noise removal. Our idea is to utilize MAD and ROAD as measures of noise probability of a pixel. Fuzzy inference system is used to justify the degree of which a pixel can be categorized as noisy. Based on the fuzzy inference result, the fuzzy switching scheme that adopts median filter as the main estimator is applied to the filtering. The GA training aims to find the best parameters for the fuzzy sets in the fuzzy noise detection. By the experimental results, the proposed method has successfully removed mixed impulse noise in low to medium probabilities, while keeping the uncorrupted pixels less affected by the median filtering. It also surpasses the other methods, either classical or soft computing-based approaches to impulse noise removal, in MAE and PSNR evaluations.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"63-70"},"PeriodicalIF":0.0,"publicationDate":"2010-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016547","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}
Relevance feedback (RF) approaches are use to improve the performance of content-based image retrieval (CBIR) systems. In this paper, a RF approach based on modification of similarity measure using particle swarm optimization (PSO) in a medical X-ray image retrieval system is proposed. In this algorithm, using PSO, the significance of each feature in the similarity measure is modified to image retrieval. This modification causes that good features have major effect in relevant image retrieval. The defined fitness function in PSO uses relevant and irrelevant retrieved images with different strategies, simultaneously. The relevant and irrelevant images are used to exhort and penalize similarity measure, respectively. To evaluate, the proposed RF is integrated to a CBIR system based on semantic classification. In this system, using merging scheme in a hierarchical structure, the overlapped classes are merged together and determined search space for each query image. The proposed RF evaluated on a database consisting of 10000 medical X-ray images of 57 classes. The proposed algorithm provides the improvement, effectiveness more than the literature.
{"title":"A RELEVANCE FEEDBACK APPROACH BASED ON MODIFICATION OF SIMILARITY MEASURE USING PARTICLE SWARM OPTIMIZATION IN A MEDICAL X-RAY IMAGE RETRIEVAL SYSTEM","authors":"H. Pourghassem","doi":"10.1234/MJEE.V4I2.254","DOIUrl":"https://doi.org/10.1234/MJEE.V4I2.254","url":null,"abstract":"Relevance feedback (RF) approaches are use to improve the performance of content-based image retrieval (CBIR) systems. In this paper, a RF approach based on modification of similarity measure using particle swarm optimization (PSO) in a medical X-ray image retrieval system is proposed. In this algorithm, using PSO, the significance of each feature in the similarity measure is modified to image retrieval. This modification causes that good features have major effect in relevant image retrieval. The defined fitness function in PSO uses relevant and irrelevant retrieved images with different strategies, simultaneously. The relevant and irrelevant images are used to exhort and penalize similarity measure, respectively. To evaluate, the proposed RF is integrated to a CBIR system based on semantic classification. In this system, using merging scheme in a hierarchical structure, the overlapped classes are merged together and determined search space for each query image. The proposed RF evaluated on a database consisting of 10000 medical X-ray images of 57 classes. The proposed algorithm provides the improvement, effectiveness more than the literature.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"14 1","pages":"9-17"},"PeriodicalIF":0.0,"publicationDate":"2010-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016491","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}
In this paper, the results of a finite element analysis are carried out on new stator geometry of a three phase longitudinal flux Linear Switched Reluctance Motor (LSRM). In the new geometry, pole shoes are affixed to the stator poles. Static and dynamic characteristics for the proposed structure have been highlighted. Motor performance for variable load conditions is discussed. The 2-Dimensional (2-D) finite element analysis (FEA) and the experimental results of this paper prove that LSRMs are one of the strong candidates for linear propulsion drive
{"title":"ANALYSIS AND EXPERIMENTAL VERIFICATION OF A LINEAR SWITCHED RELUCTANCE MOTOR HAVING SPECIAL POLE SHAPE","authors":"N. C. Lenin, R. Arumugam","doi":"10.1234/MJEE.V4I2.295","DOIUrl":"https://doi.org/10.1234/MJEE.V4I2.295","url":null,"abstract":"In this paper, the results of a finite element analysis are carried out on new stator geometry of a three phase longitudinal flux Linear Switched Reluctance Motor (LSRM). In the new geometry, pole shoes are affixed to the stator poles. Static and dynamic characteristics for the proposed structure have been highlighted. Motor performance for variable load conditions is discussed. The 2-Dimensional (2-D) finite element analysis (FEA) and the experimental results of this paper prove that LSRMs are one of the strong candidates for linear propulsion drive","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2010-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016605","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}
R. Besharati, M. Bag-Mohammadi, Mashallah AbasiDezfooli
The application Layer Multicast (ALM) is an alternative and deployable approach to IP multicasting. Topology awareness link stress and delay stretch considerably, therefore it is a very important metric for ALM. This work describes a novel, highly stable and low overhead ALM approach using a binning technique to cluster nearby receivers, referred to as Bincast. Bincast uses a constant number of landmarks to cluster nearby nodes. Then, it constructs a k-ary tree between cluster members. The most stable node is selected as the head of each cluster. Cluster heads are connected to the source through a higher level tree. Detailed performance evaluation revealed that Bincast has a lower delay stretch than similar methods with approximately the same stress. Besides, it is more stable due to the selection of stable nodes as cluster heads.
{"title":"Using Binning for Tree Construction in Application","authors":"R. Besharati, M. Bag-Mohammadi, Mashallah AbasiDezfooli","doi":"10.1234/MJEE.V3I2.290","DOIUrl":"https://doi.org/10.1234/MJEE.V3I2.290","url":null,"abstract":"The application Layer Multicast (ALM) is an alternative and deployable approach to IP multicasting. Topology awareness link stress and delay stretch considerably, therefore it is a very important metric for ALM. This work describes a novel, highly stable and low overhead ALM approach using a binning technique to cluster nearby receivers, referred to as Bincast. Bincast uses a constant number of landmarks to cluster nearby nodes. Then, it constructs a k-ary tree between cluster members. The most stable node is selected as the head of each cluster. Cluster heads are connected to the source through a higher level tree. Detailed performance evaluation revealed that Bincast has a lower delay stretch than similar methods with approximately the same stress. Besides, it is more stable due to the selection of stable nodes as cluster heads.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"3 1","pages":"43-51"},"PeriodicalIF":0.0,"publicationDate":"2010-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66015578","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}
This paper briefly reviews the different types of Switched reluctance (SR) motors with different geometries and then presents a new configuration for a two phase SR motor with step shaped rotor poles. This motor has the ability to start and run in a specified direction without any difficulties. In another words the motor will always have starting torque no matter where the rotor position is. It also presents a centrifugal switch mounted on the motor shaft for a sudden advancement of current-pulses relative to rotor position after reaching a preset motor speed in order to develop higher torque at starting. It continues with the analysis of the machine in generator mode. To evaluate the performance of switched reluctance machine in motoring as well as generating mode, two types of analysis, namely numerical technique and experimental study have been utilized. In the numerical analysis, due to highly non-linear nature of the motor, a three dimensional finite element analysis is employed, whereas in the experimental study, a proto-type motor has been built and tested.
{"title":"A Stepped Two Phase Configuration for Switched Reluctance Motor with High Starting Torque","authors":"A. Siadatan, E. Afjei","doi":"10.1234/MJEE.V4I1.157","DOIUrl":"https://doi.org/10.1234/MJEE.V4I1.157","url":null,"abstract":"This paper briefly reviews the different types of Switched reluctance (SR) motors with different geometries and then presents a new configuration for a two phase SR motor with step shaped rotor poles. This motor has the ability to start and run in a specified direction without any difficulties. In another words the motor will always have starting torque no matter where the rotor position is. It also presents a centrifugal switch mounted on the motor shaft for a sudden advancement of current-pulses relative to rotor position after reaching a preset motor speed in order to develop higher torque at starting. It continues with the analysis of the machine in generator mode. To evaluate the performance of switched reluctance machine in motoring as well as generating mode, two types of analysis, namely numerical technique and experimental study have been utilized. In the numerical analysis, due to highly non-linear nature of the motor, a three dimensional finite element analysis is employed, whereas in the experimental study, a proto-type motor has been built and tested.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2010-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016705","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}
The variations of speech parameters due to emotion or stress are noticeable. In the presence of such variations, if a neutral model is used for the system, the speech recognition accuracy deteriorates. The evaluation of how emotion influences speech parameters is the first step towards emotional speech recognition. Pitch frequency is an important parameter in speech processing systems. Therefore in this research the effect of pitch frequency and its slope due to emotion is explored for voiced phonemes. On the other hand, the influence of emotional state on continuous speech recognition performance is evaluated. The results show that the recognition performance of sentences with angry and happy states and also interrogative sentences has the most deterioration. This deterioration is more than 68% when compared to neutral speech recognition accuracy. To improve recognition results, we add the pitch frequency information to the end of speech recognizer feature vector. The amount of improvement depends on the type of emotion and also added pitch information. The results show that, pitch frequency slope has a significant affect on the improvement of speech recognition accuracy even for neutral speech.
{"title":"Pitch in Emotional Speech and Emotional Speech Recognition Using Pitch Frequency","authors":"D. Gharavian, M. Sheikhan, M. Janipour","doi":"10.1234/MJEE.V4I1.159","DOIUrl":"https://doi.org/10.1234/MJEE.V4I1.159","url":null,"abstract":"The variations of speech parameters due to emotion or stress are noticeable. In the presence of such variations, if a neutral model is used for the system, the speech recognition accuracy deteriorates. The evaluation of how emotion influences speech parameters is the first step towards emotional speech recognition. Pitch frequency is an important parameter in speech processing systems. Therefore in this research the effect of pitch frequency and its slope due to emotion is explored for voiced phonemes. On the other hand, the influence of emotional state on continuous speech recognition performance is evaluated. The results show that the recognition performance of sentences with angry and happy states and also interrogative sentences has the most deterioration. This deterioration is more than 68% when compared to neutral speech recognition accuracy. To improve recognition results, we add the pitch frequency information to the end of speech recognizer feature vector. The amount of improvement depends on the type of emotion and also added pitch information. The results show that, pitch frequency slope has a significant affect on the improvement of speech recognition accuracy even for neutral speech.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"19-24"},"PeriodicalIF":0.0,"publicationDate":"2010-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016749","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}
In this paper, a CMOS four quadrant multiplier based on flipped voltage follower and differential squaring circuit is presented. The proposed circuit has a compact architecture operating at a higher speed and a higher input voltage range compared to the previously presented structures. The transistors operate in the both saturation and ohmic regions. The circuit operates with a single supply voltage of 3.3V in a 0.35 µm CMOS technology where the total harmonic distortion (THD) is less than 1.1%, the linearity error is also less than 3%, -3db frequency is more than 180 MHz and the voltage input range is 3V . Simulation results are given to verify the functionality of the proposed multiplier.
{"title":"A High-Speed High-Input Range Four Quadrant Analog Multiplier","authors":"M. Mokaram, A. Khoei, K. Hadidi","doi":"10.1234/MJEE.V4I1.2","DOIUrl":"https://doi.org/10.1234/MJEE.V4I1.2","url":null,"abstract":"In this paper, a CMOS four quadrant multiplier based on flipped voltage follower and differential squaring circuit is presented. The proposed circuit has a compact architecture operating at a higher speed and a higher input voltage range compared to the previously presented structures. The transistors operate in the both saturation and ohmic regions. The circuit operates with a single supply voltage of 3.3V in a 0.35 µm CMOS technology where the total harmonic distortion (THD) is less than 1.1%, the linearity error is also less than 3%, -3db frequency is more than 180 MHz and the voltage input range is 3V . Simulation results are given to verify the functionality of the proposed multiplier.","PeriodicalId":37804,"journal":{"name":"Majlesi Journal of Electrical Engineering","volume":"4 1","pages":"13-17"},"PeriodicalIF":0.0,"publicationDate":"2010-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66016841","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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