Pub Date : 2008-07-20DOI: 10.1109/SSD.2008.4632784
A. Majeed, J. Hussein
This paper presents analysis, calculations, and modeling of weighted network reliability. Basic equations for the reliability evaluation are stated, and an algorithm presented for calculation of weighted network reliability and program written in FORTRAN language for implementing that. Reliability found for different both (weighted and unweighted) networks, and the results were compared.
{"title":"Weighted network reliability and modeling","authors":"A. Majeed, J. Hussein","doi":"10.1109/SSD.2008.4632784","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632784","url":null,"abstract":"This paper presents analysis, calculations, and modeling of weighted network reliability. Basic equations for the reliability evaluation are stated, and an algorithm presented for calculation of weighted network reliability and program written in FORTRAN language for implementing that. Reliability found for different both (weighted and unweighted) networks, and the results were compared.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"100 24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124697290","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632811
A.A. Ali, L. Abdul-Rahaim
Wireless digital communications is rapidly expanding resulting in a demand for systems that are reliable and have a high spectral efficiency. To fulfill these demands, the multicarrier modulation scheme, often called Multicarrier direct sequence code division multiplexing access (MC-DS-CDMA), has drawn a lot of attention. On the other hand space time block code-MC-DS-CDMA techniques have been considered to be a candidate to support multimedia services in mobile radio communications. In this work, a new structure for STBC-MC-DS-CDMA that based on discrete wavelet transform (DWT) is proposed. The proposed system has been examined with different channel models (AWGN, flat fading and selective fading) and proves that it has better BER performance than the conventional STBC-MC-DS-CDMA using FFT due to the low and high pass filters contained in the wavelet transform.
无线数字通信正在迅速发展，因此对可靠和具有高频谱效率的系统产生了需求。为了满足这些需求，多载波调制方案，通常被称为多载波直接序列码分多址(MC-DS-CDMA)，引起了人们的广泛关注。另一方面，空时块码- mc - ds - cdma技术被认为是支持移动无线电通信中多媒体业务的候选技术。本文提出了一种基于离散小波变换(DWT)的STBC-MC-DS-CDMA结构。在不同的信道模型(AWGN、平坦衰落和选择性衰落)下对该系统进行了测试，结果表明，由于小波变换中包含了低通和高通滤波器，该系统比使用FFT的传统STBC-MC-DS-CDMA具有更好的BER性能。
{"title":"Discrete wavelets transform based space time block code multicarrier direct sequence CDMA","authors":"A.A. Ali, L. Abdul-Rahaim","doi":"10.1109/SSD.2008.4632811","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632811","url":null,"abstract":"Wireless digital communications is rapidly expanding resulting in a demand for systems that are reliable and have a high spectral efficiency. To fulfill these demands, the multicarrier modulation scheme, often called Multicarrier direct sequence code division multiplexing access (MC-DS-CDMA), has drawn a lot of attention. On the other hand space time block code-MC-DS-CDMA techniques have been considered to be a candidate to support multimedia services in mobile radio communications. In this work, a new structure for STBC-MC-DS-CDMA that based on discrete wavelet transform (DWT) is proposed. The proposed system has been examined with different channel models (AWGN, flat fading and selective fading) and proves that it has better BER performance than the conventional STBC-MC-DS-CDMA using FFT due to the low and high pass filters contained in the wavelet transform.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130635625","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632778
O. Daoud
Orthogonal frequency division multiplexing (OFDM) is a promising technique in the next evolution of the mobile telephony, However it suffers from peak to average power ratio (PAPR). It is a problem for broadcast engineers in many different applications. Non-linearities can cause severe out-of-band radiation when confronted with high PAPRs. Previous work has shown that the application of coding just before the transmission frontend can help alleviate this effect. This paper presents a design for a low density parity check (LDPC) code that achieves a good error correction performance and is used to lower the PAPR in a multiple input multiple output orthogonal frequency division multiplex system. The paper will detail the results of software simulations, verified through hardware simulations that show that further reductions in PAPR can be achieved over previous work in this field. Finally, this paper will show that PAPR reduction can be achieved by employing LDPC coding prior to modulation.
{"title":"Use of LDPC to improve the MIMO-OFDM systems performance","authors":"O. Daoud","doi":"10.1109/SSD.2008.4632778","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632778","url":null,"abstract":"Orthogonal frequency division multiplexing (OFDM) is a promising technique in the next evolution of the mobile telephony, However it suffers from peak to average power ratio (PAPR). It is a problem for broadcast engineers in many different applications. Non-linearities can cause severe out-of-band radiation when confronted with high PAPRs. Previous work has shown that the application of coding just before the transmission frontend can help alleviate this effect. This paper presents a design for a low density parity check (LDPC) code that achieves a good error correction performance and is used to lower the PAPR in a multiple input multiple output orthogonal frequency division multiplex system. The paper will detail the results of software simulations, verified through hardware simulations that show that further reductions in PAPR can be achieved over previous work in this field. Finally, this paper will show that PAPR reduction can be achieved by employing LDPC coding prior to modulation.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128133775","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632796
M.R. Khadraoui, M. Elleuch
A comparison of the performances between the OptiSlip pitch regulated wind system (Vestas V39-600) and a fixed speed stall regulated wind system of the same power. This comparison will relate to the quality of the power generated by each of the two systems and their stabilities following a grid fault.
{"title":"Comparison between OptiSlip and Fixed Speed wind energy conversion systems","authors":"M.R. Khadraoui, M. Elleuch","doi":"10.1109/SSD.2008.4632796","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632796","url":null,"abstract":"A comparison of the performances between the OptiSlip pitch regulated wind system (Vestas V39-600) and a fixed speed stall regulated wind system of the same power. This comparison will relate to the quality of the power generated by each of the two systems and their stabilities following a grid fault.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"13 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134560786","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632896
T. Tutunji, A. Saleem
A method to identify and control a mechatronic system in real time environment is presented in this paper. Acquiring the systempsilas transfer function accurately can be difficult if some parameters are missing. This causes a great difficulty in the system modeling and control. Therefore in this research, a method based on Hardware-in-the-Loop (HIL) concept has been employed to identify and control dynamic systems. Online identification using Auto Regressive Moving Average (ARMA) models is used to identify the transfer function of the system; the controller is tuned on the identified model in a simulation environment and applied to the real system. The advantages of the proposed method are high accuracy in the identified system, simplicity, and low cost. Two case studies, namely, a DC motor and servo-pneumatic system, were used to verify the proposed method.
{"title":"A method for on-line identification and control based on hardware-in-the-loop concept","authors":"T. Tutunji, A. Saleem","doi":"10.1109/SSD.2008.4632896","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632896","url":null,"abstract":"A method to identify and control a mechatronic system in real time environment is presented in this paper. Acquiring the systempsilas transfer function accurately can be difficult if some parameters are missing. This causes a great difficulty in the system modeling and control. Therefore in this research, a method based on Hardware-in-the-Loop (HIL) concept has been employed to identify and control dynamic systems. Online identification using Auto Regressive Moving Average (ARMA) models is used to identify the transfer function of the system; the controller is tuned on the identified model in a simulation environment and applied to the real system. The advantages of the proposed method are high accuracy in the identified system, simplicity, and low cost. Two case studies, namely, a DC motor and servo-pneumatic system, were used to verify the proposed method.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133416324","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632868
S. Mahjoub, F. Mnif, Nabil Derbel
Controlling an underactuated manipulator with less actuators than degree of freedom is a challenging problem, specifically when it is to force the underactuated manipulator to track a given trajectory or to be configurated at a specific position in the work space. This paper presents a cascade sliding mode tracking controller for set-point regulation of 2-DOF underactuated manipulators. This work builds on an observation that an underactuated manipulator can be treated as two subsystems. Consequently, a cascade sliding mode tracking controller can be designed as follows. First, a sliding mode surface is designed for both subsystems, this two sliding surfaces represent a first layer in the design architecture. A second layer sliding mode surface is then constructed based on the first layer sliding surface. The cascaded sliding mode controller is therefor deduced in terms of Lyapunov stability theorem. Robustness issues to bounded disturbances are then investigated. Simulation results on 2-DOF whiling pendulum are presented to demonstrate the effectiveness of the approach.
{"title":"Variable structure control for set-point stabilization OF 2-DOF underactuated manipulators","authors":"S. Mahjoub, F. Mnif, Nabil Derbel","doi":"10.1109/SSD.2008.4632868","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632868","url":null,"abstract":"Controlling an underactuated manipulator with less actuators than degree of freedom is a challenging problem, specifically when it is to force the underactuated manipulator to track a given trajectory or to be configurated at a specific position in the work space. This paper presents a cascade sliding mode tracking controller for set-point regulation of 2-DOF underactuated manipulators. This work builds on an observation that an underactuated manipulator can be treated as two subsystems. Consequently, a cascade sliding mode tracking controller can be designed as follows. First, a sliding mode surface is designed for both subsystems, this two sliding surfaces represent a first layer in the design architecture. A second layer sliding mode surface is then constructed based on the first layer sliding surface. The cascaded sliding mode controller is therefor deduced in terms of Lyapunov stability theorem. Robustness issues to bounded disturbances are then investigated. Simulation results on 2-DOF whiling pendulum are presented to demonstrate the effectiveness of the approach.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131930702","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632835
Q. Ali
Industrial Ethernet and WLAN have entered strongly into the fields of control and automation. Nowadays, data acquisition products offer many options regarding the networking of there devices using the above techniques. However, the planners and designer who used networked industrial products need to virtually test the performance of their automated or controlled systems prior to its installation. This paper presents a new simulation methodology of networked industrial devices using academic OPNET IT GURU package. This methodology is based on supplying the planners with a simple GUI and ready to use industrial models. In this work, a complete library of national instrument (NI) devices was built. The simulation method was given in details and several examples were demonstrated. A complex real time substation automation system was simulated using a variety of simulated NI devices and the effect of the different parameters (network speed, topology, nodes performance, network stack, etc...) is examined. It was found that this simulation method with its full NI devices library would enhance the planning process and abstract the time required for project building.
工业以太网和无线局域网已进入控制和自动化领域。如今，数据采集产品提供了许多关于使用上述技术的设备联网的选择。然而，使用联网工业产品的规划人员和设计师需要在安装之前虚拟测试其自动化或控制系统的性能。本文提出了一种利用学术OPNET IT GURU软件包的网络化工业设备仿真新方法。这种方法的基础是为规划人员提供一个简单的GUI，并准备使用工业模型。在这项工作中，建立了一个完整的国家仪器(NI)器件库。给出了详细的仿真方法，并给出了算例。采用多种仿真NI器件对复杂的变电站实时自动化系统进行了仿真，考察了不同参数(网络速度、拓扑结构、节点性能、网络堆栈等)对系统的影响。结果表明，该仿真方法具有完整的NI器件库，可以提高规划过程并缩短项目构建所需的时间。
{"title":"An efficient simulation methodology of networked industrial devices","authors":"Q. Ali","doi":"10.1109/SSD.2008.4632835","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632835","url":null,"abstract":"Industrial Ethernet and WLAN have entered strongly into the fields of control and automation. Nowadays, data acquisition products offer many options regarding the networking of there devices using the above techniques. However, the planners and designer who used networked industrial products need to virtually test the performance of their automated or controlled systems prior to its installation. This paper presents a new simulation methodology of networked industrial devices using academic OPNET IT GURU package. This methodology is based on supplying the planners with a simple GUI and ready to use industrial models. In this work, a complete library of national instrument (NI) devices was built. The simulation method was given in details and several examples were demonstrated. A complex real time substation automation system was simulated using a variety of simulated NI devices and the effect of the different parameters (network speed, topology, nodes performance, network stack, etc...) is examined. It was found that this simulation method with its full NI devices library would enhance the planning process and abstract the time required for project building.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133622325","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632848
S. Ghorbel, M. Ben Jmeaa, M. Chtourou
In this paper, a new SVM (Support Vector Machines) synthesis method is presented. This method is based essentially on training criterion optimization of this machine by a set of hierarchical structures of learning automata. This methodology is adopted for the development of off-line isolated handwritten digits recognition system. A comparison is taken between this new approach and that of a standard approach for SVM synthesis. These two methodologies are also compared with a neural network based classification method. The obtained results show the performances of the new suggested method for SVM synthesis.
{"title":"SVM synthesis by hierarchical structures of learning automata application for handwritten digits recognition","authors":"S. Ghorbel, M. Ben Jmeaa, M. Chtourou","doi":"10.1109/SSD.2008.4632848","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632848","url":null,"abstract":"In this paper, a new SVM (Support Vector Machines) synthesis method is presented. This method is based essentially on training criterion optimization of this machine by a set of hierarchical structures of learning automata. This methodology is adopted for the development of off-line isolated handwritten digits recognition system. A comparison is taken between this new approach and that of a standard approach for SVM synthesis. These two methodologies are also compared with a neural network based classification method. The obtained results show the performances of the new suggested method for SVM synthesis.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124808053","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632827
A. Mohamed, Ying Weng, Jianmin Jiang, S. Ipson
This paper proposes a robust schema for face detection system via Gaussian mixture model to segment image based on skin color. After skin and non skin face candidatespsila selection, features are extracted directly from discrete cosine transform (DCT) coefficients computed from these candidates. Moreover, the back-propagation neural networks are used to train and classify faces based on DCT feature coefficients in Cb and Cr color spaces. This schema utilizes the skin color information, which is the main feature of face detection. DCT feature values of faces, representing the data set of skin/non-skin face candidates obtained from Gaussian mixture model are fed into the back-propagation neural networks to classify whether the original image includes a face or not. Experimental results shows that the proposed schema is reliable for face detection, and pattern features are detected and classified accurately by the backpropagation neural networks.
{"title":"Face detection based neural networks using robust skin color segmentation","authors":"A. Mohamed, Ying Weng, Jianmin Jiang, S. Ipson","doi":"10.1109/SSD.2008.4632827","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632827","url":null,"abstract":"This paper proposes a robust schema for face detection system via Gaussian mixture model to segment image based on skin color. After skin and non skin face candidatespsila selection, features are extracted directly from discrete cosine transform (DCT) coefficients computed from these candidates. Moreover, the back-propagation neural networks are used to train and classify faces based on DCT feature coefficients in Cb and Cr color spaces. This schema utilizes the skin color information, which is the main feature of face detection. DCT feature values of faces, representing the data set of skin/non-skin face candidates obtained from Gaussian mixture model are fed into the back-propagation neural networks to classify whether the original image includes a face or not. Experimental results shows that the proposed schema is reliable for face detection, and pattern features are detected and classified accurately by the backpropagation neural networks.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124919069","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 : 2008-07-20DOI: 10.1109/SSD.2008.4632899
M. Al-Qdah, M. Sharawi
In this paper, the performance of the subcarrier multiplexed (SCM) system employing binary phase shift keying (BPSK) modulation as microwave subcarrier modulation and Optical Single Sideband (OSSB) modulation was analyzed and investigated by simulation through the use of OptSim software. The BPSK modulation technique was used because of its ability to provide high spectral efficiency and simple demodulation. The OSSB modulation was preferred in this system due to its advantage of high bandwidth efficiency. The system performance was investigated by varying the performance parameters of the components used, such as data rate of the source, optical modulation index (OMI), subcarrier frequency, phase shift difference between branches of the dual-arm Mach-Zehnder (MZ) modulator, fiber length and phase of the local carrier at the demodulator. The performance of the system was optimized by making tradeoffs between these performance parameters.
{"title":"Analysis of the performance of Subcarrier Multiplexed transmission system employing OSSB modulation","authors":"M. Al-Qdah, M. Sharawi","doi":"10.1109/SSD.2008.4632899","DOIUrl":"https://doi.org/10.1109/SSD.2008.4632899","url":null,"abstract":"In this paper, the performance of the subcarrier multiplexed (SCM) system employing binary phase shift keying (BPSK) modulation as microwave subcarrier modulation and Optical Single Sideband (OSSB) modulation was analyzed and investigated by simulation through the use of OptSim software. The BPSK modulation technique was used because of its ability to provide high spectral efficiency and simple demodulation. The OSSB modulation was preferred in this system due to its advantage of high bandwidth efficiency. The system performance was investigated by varying the performance parameters of the components used, such as data rate of the source, optical modulation index (OMI), subcarrier frequency, phase shift difference between branches of the dual-arm Mach-Zehnder (MZ) modulator, fiber length and phase of the local carrier at the demodulator. The performance of the system was optimized by making tradeoffs between these performance parameters.","PeriodicalId":267264,"journal":{"name":"2008 5th International Multi-Conference on Systems, Signals and Devices","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125252917","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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