Pub Date : 2008-04-07DOI: 10.1109/ICTTA.2008.4530113
M. Elbouz, A. Alfalou, H. Hamam, Siwar Rekik
In our society based on communication, the barrier between the spoken and gestural languages remains a main problem for the deaf-mute. To make this communication possible, we propose developing an interface with two modules (comprehension and recognition) allowing the recognition and the restitution of the sign language in the form of synthesized words.
{"title":"A recognition sign language system based on the correlation technique","authors":"M. Elbouz, A. Alfalou, H. Hamam, Siwar Rekik","doi":"10.1109/ICTTA.2008.4530113","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530113","url":null,"abstract":"In our society based on communication, the barrier between the spoken and gestural languages remains a main problem for the deaf-mute. To make this communication possible, we propose developing an interface with two modules (comprehension and recognition) allowing the recognition and the restitution of the sign language in the form of synthesized words.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122306387","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530371
M. Zennaki, A. Ech-cherif
We investigate the possibility of using kernel clustering and data fusion techniques for solving hard combinatorial optimization problems. The proposed general paradigm aims at incorporating unsupervised kernel methods into population-based heuristics, which rely on spatial fusion of solutions, in order to learn the solution clusters from the search history. This form of extracted knowledge guides the heuristic to detect automatically promising regions of solutions. The proposed algorithm derived from this paradigm is an extension of the classical scatter search and can automatically learn during the search process by exploiting the history of solutions found. Preliminary results, with an application to the well-known vehicle routing problem (VRP) show the great interest of such paradigm and can effectively find near-optimal solutions for large problem instances.
{"title":"A New Approach using Machine Learning and Data Fusion Techniques for Solving Hard Combinatorial Optimization Problems","authors":"M. Zennaki, A. Ech-cherif","doi":"10.1109/ICTTA.2008.4530371","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530371","url":null,"abstract":"We investigate the possibility of using kernel clustering and data fusion techniques for solving hard combinatorial optimization problems. The proposed general paradigm aims at incorporating unsupervised kernel methods into population-based heuristics, which rely on spatial fusion of solutions, in order to learn the solution clusters from the search history. This form of extracted knowledge guides the heuristic to detect automatically promising regions of solutions. The proposed algorithm derived from this paradigm is an extension of the classical scatter search and can automatically learn during the search process by exploiting the history of solutions found. Preliminary results, with an application to the well-known vehicle routing problem (VRP) show the great interest of such paradigm and can effectively find near-optimal solutions for large problem instances.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126062393","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530219
H. K. Bizaki, A. Falahati
Nonlinear Tomlinson Harashima precoding (THP), considered in this paper, is an attractive solution for a scenario in which multiple antenna are deployed at both the transmitter and receiver side so that cooperation among them is possible. In literature THP filters has been calculated and optimized with zero forcing (ZF) and minimum mean square error (MMSE) criteria with the assumption that complete Channel State Information (CSI) is available in transmitter side. In this paper we compute maximum achievable rate of this system by means of information theory concepts. A good solution for maximum achievable rate and optimum as well as suboptimum solutions are presented. For simplicity of calculations, closed form upper bound is attained by neglecting spatially interference term. Moreover, lower bound is obtained by some extra computations on mutual information. Generalization of THP (GTHP) in structure of spatial THP is considered, too. GTHP structure enables different transmission power per antenna so we attained an optimal power allocation to minimize Symbol Error Rate (SER) of each sub channels. In addition the maximum achievable rate of GTHP is calculated for general case.
{"title":"Achievable Rates and Power Loading in MIMO-THP Systems","authors":"H. K. Bizaki, A. Falahati","doi":"10.1109/ICTTA.2008.4530219","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530219","url":null,"abstract":"Nonlinear Tomlinson Harashima precoding (THP), considered in this paper, is an attractive solution for a scenario in which multiple antenna are deployed at both the transmitter and receiver side so that cooperation among them is possible. In literature THP filters has been calculated and optimized with zero forcing (ZF) and minimum mean square error (MMSE) criteria with the assumption that complete Channel State Information (CSI) is available in transmitter side. In this paper we compute maximum achievable rate of this system by means of information theory concepts. A good solution for maximum achievable rate and optimum as well as suboptimum solutions are presented. For simplicity of calculations, closed form upper bound is attained by neglecting spatially interference term. Moreover, lower bound is obtained by some extra computations on mutual information. Generalization of THP (GTHP) in structure of spatial THP is considered, too. GTHP structure enables different transmission power per antenna so we attained an optimal power allocation to minimize Symbol Error Rate (SER) of each sub channels. In addition the maximum achievable rate of GTHP is calculated for general case.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114239183","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530264
M. Moradian, M. Khalaj‐Amirhosseini
In this paper a suitable method is presented which allows it to effectively remove the first spurious pass-bands. The proposed filter configuration is constructed by adding three appropriate capacitors between each coupled line and three attached open-circuit stubs at each line of the conventional coupled-line filter. The capacitors and stubs are placed at the middle and each end of the coupled-lines. Placing the capacitors lead to equal modal phase velocities and shorten coupled-line lengths. In order to demonstrate the characteristics of the proposed filter, a third order band-pass filter centered at the operating frequency 1 GHz with 20% fractional bandwidth is designed and simulated. The simulated results show for such a filter prototype, the first spurious response is effectively suppressed.
{"title":"First spurious suppression in microstrip parallel-coupled line filters using compensated capacitors and stubs","authors":"M. Moradian, M. Khalaj‐Amirhosseini","doi":"10.1109/ICTTA.2008.4530264","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530264","url":null,"abstract":"In this paper a suitable method is presented which allows it to effectively remove the first spurious pass-bands. The proposed filter configuration is constructed by adding three appropriate capacitors between each coupled line and three attached open-circuit stubs at each line of the conventional coupled-line filter. The capacitors and stubs are placed at the middle and each end of the coupled-lines. Placing the capacitors lead to equal modal phase velocities and shorten coupled-line lengths. In order to demonstrate the characteristics of the proposed filter, a third order band-pass filter centered at the operating frequency 1 GHz with 20% fractional bandwidth is designed and simulated. The simulated results show for such a filter prototype, the first spurious response is effectively suppressed.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120944734","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530233
O. Khalifa, T. Al-maznaee, M. Munjid, A. Hussan
This In this paper, Convolutional coder software implementation using Viterbi decoding algorithm for bitstream that has been encoded using Forward error correction is presented. It will discuss the detailed description and the steps involved in simulating a communication channel using convolutional encoding with Viterbi decoding. The steps will involve generating random binary data, convolutionally encoding the data, passing the encoded data through a noisy channel, quantizing the received channel symbols, and finally performing Viterbi decoding on the quantized channel symbols to recover the original binary data. The paper will be in a convincing manner and authors aim to explain to the reader the advantages of convolutional coding with Viterbi decoding over conventional decoding techniques in terms of BER.
{"title":"Convolution Coder Software Implementation Using VIiterbiDecoding Algorithm","authors":"O. Khalifa, T. Al-maznaee, M. Munjid, A. Hussan","doi":"10.1109/ICTTA.2008.4530233","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530233","url":null,"abstract":"This In this paper, Convolutional coder software implementation using Viterbi decoding algorithm for bitstream that has been encoded using Forward error correction is presented. It will discuss the detailed description and the steps involved in simulating a communication channel using convolutional encoding with Viterbi decoding. The steps will involve generating random binary data, convolutionally encoding the data, passing the encoded data through a noisy channel, quantizing the received channel symbols, and finally performing Viterbi decoding on the quantized channel symbols to recover the original binary data. The paper will be in a convincing manner and authors aim to explain to the reader the advantages of convolutional coding with Viterbi decoding over conventional decoding techniques in terms of BER.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"270 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125270699","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530220
H. K. Bizaki, A. Falahati
This paper considers the Tomlinson-Harashima Precoding (THP) when using over multiple antenna system. In spite of its good performance, THP is very sensitive to erroneous Channel State Information (CSI) i.e., its performance largely depend on channel estimation accuracy. Most algorithms that employed in channel estimators are training based. In this paper, a correlation-based algorithm is proposed in order to estimate channel in blind method, where it does not require any training sequence for channel estimation. The CSI can be identified by an Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT)-like method and Singular Value Decomposition (SVD). In particular, we focus on the THP performance with respect to the channel estimation errors by employing spatial power loading which provides significant improvement with respect to conventional methods. We develop this loading for the THP in minimum average Symbol Error Rate (SER) sense. Simulation results are used to show the performance advantage attained by the power loading in blind channel estimation scenario.
{"title":"MIMO Precoding with ESPRIT-Like Blind Channel Estimation","authors":"H. K. Bizaki, A. Falahati","doi":"10.1109/ICTTA.2008.4530220","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530220","url":null,"abstract":"This paper considers the Tomlinson-Harashima Precoding (THP) when using over multiple antenna system. In spite of its good performance, THP is very sensitive to erroneous Channel State Information (CSI) i.e., its performance largely depend on channel estimation accuracy. Most algorithms that employed in channel estimators are training based. In this paper, a correlation-based algorithm is proposed in order to estimate channel in blind method, where it does not require any training sequence for channel estimation. The CSI can be identified by an Estimation of Signal Parameters via Rotational Invariance Techniques (ESPRIT)-like method and Singular Value Decomposition (SVD). In particular, we focus on the THP performance with respect to the channel estimation errors by employing spatial power loading which provides significant improvement with respect to conventional methods. We develop this loading for the THP in minimum average Symbol Error Rate (SER) sense. Simulation results are used to show the performance advantage attained by the power loading in blind channel estimation scenario.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123857057","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530359
A. Hameurlain, F. Morvan, Mahmoud El Samad
Today the grid computing, intended initially for the intensive computing, open towards the management of voluminous, heterogeneous, and distributed data on a large-scale environment. The grid data management raises new problems and presents real challenges: resource discovery, efficiency of access, autonomic management, security, and benchmarking. This importance comes out of characteristics offered by grid systems: autonomy, heterogeneity and dynamicity of nodes. Firstly, we recall the fundamental problems of the large scale data management in grid systems and characteristics of these systems. Then, we describe in a highlight way proposed approaches (Web services, P2P techniques, Agent-based approach) for resource discovery. The remainder of the paper is devoted to point out the contributions of mobile agents for some problems of large scale data management, in particularly: dynamic query optimization, task placement, and embedded cost model. We show how mobile agents can help for decentralized control, and scaling.
{"title":"Large Scale Data Management in Grid Systems: a Survey","authors":"A. Hameurlain, F. Morvan, Mahmoud El Samad","doi":"10.1109/ICTTA.2008.4530359","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530359","url":null,"abstract":"Today the grid computing, intended initially for the intensive computing, open towards the management of voluminous, heterogeneous, and distributed data on a large-scale environment. The grid data management raises new problems and presents real challenges: resource discovery, efficiency of access, autonomic management, security, and benchmarking. This importance comes out of characteristics offered by grid systems: autonomy, heterogeneity and dynamicity of nodes. Firstly, we recall the fundamental problems of the large scale data management in grid systems and characteristics of these systems. Then, we describe in a highlight way proposed approaches (Web services, P2P techniques, Agent-based approach) for resource discovery. The remainder of the paper is devoted to point out the contributions of mobile agents for some problems of large scale data management, in particularly: dynamic query optimization, task placement, and embedded cost model. We show how mobile agents can help for decentralized control, and scaling.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"144 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113985935","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530057
P. Mahale
In this paper segment variable-step-size proportionate normalized least mean square (SVS-PNLMS) algorithm is proposed for acoustic echo cancellation (AEC) application which is introduced as an important issue in services like video conferencing. The analysis reveals that the proposed SVS-PNLMS algorithm performs faster convergence rate compared to that of the recently introduced SPNLMS (segment proportionate normalized least mean square) or PNLMS (proportionate normalized least mean square) algorithms. Compared with its proportionate counterparts including PNLMS and SPNLMS, the proposed SVS-PNLMS algorithm not only results in a faster convergence rate for both white and colored noise inputs, but also preserves this initial fast convergence rate until it reaches to steady state. It also presents a higher tracking behavior for quasi-stationary inputs such as speech signal in addition to better performance in terms of computational complexity and resulting ERLE (echo return loss enhancement).
{"title":"SVSPNLMS Algorithm for Acoustic Echo Cancellation","authors":"P. Mahale","doi":"10.1109/ICTTA.2008.4530057","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530057","url":null,"abstract":"In this paper segment variable-step-size proportionate normalized least mean square (SVS-PNLMS) algorithm is proposed for acoustic echo cancellation (AEC) application which is introduced as an important issue in services like video conferencing. The analysis reveals that the proposed SVS-PNLMS algorithm performs faster convergence rate compared to that of the recently introduced SPNLMS (segment proportionate normalized least mean square) or PNLMS (proportionate normalized least mean square) algorithms. Compared with its proportionate counterparts including PNLMS and SPNLMS, the proposed SVS-PNLMS algorithm not only results in a faster convergence rate for both white and colored noise inputs, but also preserves this initial fast convergence rate until it reaches to steady state. It also presents a higher tracking behavior for quasi-stationary inputs such as speech signal in addition to better performance in terms of computational complexity and resulting ERLE (echo return loss enhancement).","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"156 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122615067","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4530330
B. Kosayba, H. Alkhedr, F. Jdeed, A. Shriedi, E. Al-mozaien
In this paper we discuss a new important technology which is a VoiceXML the markup language for browsing sites or providing services among human speech over the network (internet or other). We suggest a platform to add Arabic support to this technology. We introduce this technology and its methodology (how to work). Since that this technology requires the user to own some major components such as VoiceXML browser, Arabic TTS and Arabic ASR, we describe these components in some details. The paper firstly introduces the VoiceXML, then it explains the architecture of the VoiceXML browser in details, after that it discusses the specifications of Arabic language, next it discusses the method of building Arabic TTS and Arabic ASR and their architecture.
{"title":"Arabic Phonetic Web Sites Platform Using VoiceXML","authors":"B. Kosayba, H. Alkhedr, F. Jdeed, A. Shriedi, E. Al-mozaien","doi":"10.1109/ICTTA.2008.4530330","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4530330","url":null,"abstract":"In this paper we discuss a new important technology which is a VoiceXML the markup language for browsing sites or providing services among human speech over the network (internet or other). We suggest a platform to add Arabic support to this technology. We introduce this technology and its methodology (how to work). Since that this technology requires the user to own some major components such as VoiceXML browser, Arabic TTS and Arabic ASR, we describe these components in some details. The paper firstly introduces the VoiceXML, then it explains the architecture of the VoiceXML browser in details, after that it discusses the specifications of Arabic language, next it discusses the method of building Arabic TTS and Arabic ASR and their architecture.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131273365","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 : 2008-04-07DOI: 10.1109/ICTTA.2008.4529992
A. Bazghandi, A. Pouyan
One of prevalent system modeling approaches is multi agent simulation (MAS). In this modeling approach, geographic information system (GIS) is by now a more or less common issue in a lot of theoretical and practical applications. GIS and MAS address space in different perspectives. While GIS enables scientists and engineers to model geographic space, MAS models the behavior of intelligent agents within geographic space. Buyer and seller proposition is one of the most studied systems. In this paper, buyer and seller agents transact in a GIS environment. Buyer agent buys from seller according to the adjacency to market place, buyer incoming status, quality of commodity and buying mentality background. The buyer models the farness from sellers, trusty of the seller after having purchased goods from it.
{"title":"Considering Geographic Information Systems In Buyer/Seller Agents Simulation","authors":"A. Bazghandi, A. Pouyan","doi":"10.1109/ICTTA.2008.4529992","DOIUrl":"https://doi.org/10.1109/ICTTA.2008.4529992","url":null,"abstract":"One of prevalent system modeling approaches is multi agent simulation (MAS). In this modeling approach, geographic information system (GIS) is by now a more or less common issue in a lot of theoretical and practical applications. GIS and MAS address space in different perspectives. While GIS enables scientists and engineers to model geographic space, MAS models the behavior of intelligent agents within geographic space. Buyer and seller proposition is one of the most studied systems. In this paper, buyer and seller agents transact in a GIS environment. Buyer agent buys from seller according to the adjacency to market place, buyer incoming status, quality of commodity and buying mentality background. The buyer models the farness from sellers, trusty of the seller after having purchased goods from it.","PeriodicalId":330215,"journal":{"name":"2008 3rd International Conference on Information and Communication Technologies: From Theory to Applications","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121878505","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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