Pub Date : 2009-09-01DOI: 10.1109/YCICT.2009.5382391
Zhenkai Zhang, Zhihua Liu, Jianbin Jiao
A multi-channel video display system based on a high performance DSP, TMS320DM642, has been put forward in this paper. Compared with the traditional video systems, this system provides a broader view for users and more information in one frame of output video flow. In the system SIFT features are employed for image matching, on which we develop the automatic image stitching procedure. Both matching and stitching are implemented on the DSP, the former in the system initialization stage and the latter in the whole working process. In addition, several optimization approaches based on the DM642's properties are carried out to make the system work in real-time. Experiments validate the effectiveness and efficiency of the system.
{"title":"DSP implementation of a multi-channel video display system with image stitching","authors":"Zhenkai Zhang, Zhihua Liu, Jianbin Jiao","doi":"10.1109/YCICT.2009.5382391","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382391","url":null,"abstract":"A multi-channel video display system based on a high performance DSP, TMS320DM642, has been put forward in this paper. Compared with the traditional video systems, this system provides a broader view for users and more information in one frame of output video flow. In the system SIFT features are employed for image matching, on which we develop the automatic image stitching procedure. Both matching and stitching are implemented on the DSP, the former in the system initialization stage and the latter in the whole working process. In addition, several optimization approaches based on the DM642's properties are carried out to make the system work in real-time. Experiments validate the effectiveness and efficiency of the system.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130838788","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382392
Fangjin Zhu, Xiangxu Meng, Hua Wang, Shanwen Yi
Large-scale deployment of multicast applications is limited by the number of states that are set in routers for multicast groups. As a new approach to multicast state reduction, aggregated multicast forces multiple multicast groups sharing a common distribution tree. An ant colony optimization algorithm to aggregated multicast is proposed. Inspired by bin packing problem, relative fullness is used as an important component to define fitness function. To improve the algorithm's convergence time, heuristic information is introduced according to changes of aggregated trees' bandwidth waste rate. After each iteration a new pheromone update rule is proposed. Simulation results show that this algorithm performs well in scenarios with bigger bandwidth waste rate or larger network scale. Compared with greedy algorithm by running for the same amount of time and in the same network topology, the algorithm has better optimization performance.
{"title":"An ant colony optimization algorithm to aggregated multicast using the idea of bin packing","authors":"Fangjin Zhu, Xiangxu Meng, Hua Wang, Shanwen Yi","doi":"10.1109/YCICT.2009.5382392","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382392","url":null,"abstract":"Large-scale deployment of multicast applications is limited by the number of states that are set in routers for multicast groups. As a new approach to multicast state reduction, aggregated multicast forces multiple multicast groups sharing a common distribution tree. An ant colony optimization algorithm to aggregated multicast is proposed. Inspired by bin packing problem, relative fullness is used as an important component to define fitness function. To improve the algorithm's convergence time, heuristic information is introduced according to changes of aggregated trees' bandwidth waste rate. After each iteration a new pheromone update rule is proposed. Simulation results show that this algorithm performs well in scenarios with bigger bandwidth waste rate or larger network scale. Compared with greedy algorithm by running for the same amount of time and in the same network topology, the algorithm has better optimization performance.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131261376","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382398
Xinda Ke, Funian Li, Wencheng Gao
Cooperative communication in multi-user orthogonal frequency division multiplexing (MU-OFDM) networks is a promising solution to combat wireless channel fading and to increase system throughput. In this paper, with the instantaneous channel state information (CSI) available at base station, the optimal resource allocation strategy is considered in MU-OFDM networks, which is to maximize throughput and ensure fairness in entire network. We show that this problem is formulated as a mixed binary integer programming problem. Thus we decompose this optimization problem into four sub-optimal problems. First, the dynamic user choosing strategy is proposed. Second, a subcarrier choosing strategy is given by making use of the equivalent channel power gain. And the adaptive power allocation scheme in base station and in relay station is given at last. The simulation results show that our proposed algorithm can greatly increase throughput and ensure fairness.
{"title":"Adaptive resource allocation in cooperative OFDM networks for throughput and fairness improvement","authors":"Xinda Ke, Funian Li, Wencheng Gao","doi":"10.1109/YCICT.2009.5382398","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382398","url":null,"abstract":"Cooperative communication in multi-user orthogonal frequency division multiplexing (MU-OFDM) networks is a promising solution to combat wireless channel fading and to increase system throughput. In this paper, with the instantaneous channel state information (CSI) available at base station, the optimal resource allocation strategy is considered in MU-OFDM networks, which is to maximize throughput and ensure fairness in entire network. We show that this problem is formulated as a mixed binary integer programming problem. Thus we decompose this optimization problem into four sub-optimal problems. First, the dynamic user choosing strategy is proposed. Second, a subcarrier choosing strategy is given by making use of the equivalent channel power gain. And the adaptive power allocation scheme in base station and in relay station is given at last. The simulation results show that our proposed algorithm can greatly increase throughput and ensure fairness.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132117154","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382384
Jing An, Chang Li, Bin Li
Clustering is an important concept for mobile ad hoc networks (MANETs), because clustering makes it possible to guarantee basic levels of system performance, such as throughput, delay and also security issues such as availability, in the presence of both mobility and large number mobile terminals. Many clustering protocols for MANETs have been proposed in the literature. As a newly proposed weighing-based clustering algorithm, the Weighted Clustering Algorithm (WCA) has excellent performance compared with other previous clustering algorithms. However, the high mobility of nodes will lead to high frequency of re-affiliations which will increase the network overhead and minimize the network lifetime. To solve this problem, we propose an improved weight based clustering algorithm (iWCA), the goals of the algorithm are maintaining stable clustering structure, minimizing the overhead for the clustering set up, maximizing lifetime of nodes in the system, and achieving good performance. The simulation results demonstrate the superior performance of the proposed algorithm.
{"title":"A improved weight based clustering algorithm in mobile ad hoc networks","authors":"Jing An, Chang Li, Bin Li","doi":"10.1109/YCICT.2009.5382384","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382384","url":null,"abstract":"Clustering is an important concept for mobile ad hoc networks (MANETs), because clustering makes it possible to guarantee basic levels of system performance, such as throughput, delay and also security issues such as availability, in the presence of both mobility and large number mobile terminals. Many clustering protocols for MANETs have been proposed in the literature. As a newly proposed weighing-based clustering algorithm, the Weighted Clustering Algorithm (WCA) has excellent performance compared with other previous clustering algorithms. However, the high mobility of nodes will lead to high frequency of re-affiliations which will increase the network overhead and minimize the network lifetime. To solve this problem, we propose an improved weight based clustering algorithm (iWCA), the goals of the algorithm are maintaining stable clustering structure, minimizing the overhead for the clustering set up, maximizing lifetime of nodes in the system, and achieving good performance. The simulation results demonstrate the superior performance of the proposed algorithm.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132138129","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382329
Shenshen Liang, Cheng Wang, Ying Liu, Liheng Jian
Recent development in Graphics Processing Units (GPUs) has enabled inexpensive high performance computing for general-purpose applications. Due to GPU's tremendous computing capability, it has emerged as the co-processor of the CPU to achieve a high overall throughput. CUDA programming model provides the programmers adequate C language like APIs to better exploit the parallel power of the GPU. K-nearest neighbor is a widely used classification technique and has significant applications in various domains. The computational-intensive nature of KNN requires a high performance implementation. In this paper, we present a CUDA-based parallel implementation of KNN, CUKNN, using CUDA multi-thread model. Various CUDA optimization techniques are applied to maximize the utilization of the GPU. CUKNN outperforms significantly and achieve up to 15.2X speedup. It also shows good scalability when varying the dimension of the training dataset and the number of records in training dataset.
{"title":"CUKNN: A parallel implementation of K-nearest neighbor on CUDA-enabled GPU","authors":"Shenshen Liang, Cheng Wang, Ying Liu, Liheng Jian","doi":"10.1109/YCICT.2009.5382329","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382329","url":null,"abstract":"Recent development in Graphics Processing Units (GPUs) has enabled inexpensive high performance computing for general-purpose applications. Due to GPU's tremendous computing capability, it has emerged as the co-processor of the CPU to achieve a high overall throughput. CUDA programming model provides the programmers adequate C language like APIs to better exploit the parallel power of the GPU. K-nearest neighbor is a widely used classification technique and has significant applications in various domains. The computational-intensive nature of KNN requires a high performance implementation. In this paper, we present a CUDA-based parallel implementation of KNN, CUKNN, using CUDA multi-thread model. Various CUDA optimization techniques are applied to maximize the utilization of the GPU. CUKNN outperforms significantly and achieve up to 15.2X speedup. It also shows good scalability when varying the dimension of the training dataset and the number of records in training dataset.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134559431","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382451
L. Pingping, Pei Tengda, Pei Bingnan, Hu Lijun
LMS (Least Mean Square) algorithm is widely used due to its simple and stable performance. As is well known, there is an inherent conflict between the convergence rate and stead-state misadjustment, which can be overcome through the adjustment of size factor. The paper has analyzed some LMS algorithms that already existed and a new improved variable step-size LMS algorithm is presented. The computer simulation results are consistent with the theoretic analysis, ?which show that the algorithm not only has a faster convergence rate, but also has a smaller steady-state error.
{"title":"An improverd variable step size LMS adaptive filtering algorithm","authors":"L. Pingping, Pei Tengda, Pei Bingnan, Hu Lijun","doi":"10.1109/YCICT.2009.5382451","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382451","url":null,"abstract":"LMS (Least Mean Square) algorithm is widely used due to its simple and stable performance. As is well known, there is an inherent conflict between the convergence rate and stead-state misadjustment, which can be overcome through the adjustment of size factor. The paper has analyzed some LMS algorithms that already existed and a new improved variable step-size LMS algorithm is presented. The computer simulation results are consistent with the theoretic analysis, ?which show that the algorithm not only has a faster convergence rate, but also has a smaller steady-state error.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133280487","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382320
Zhenyu Chen, Jingye Zhou, Yiqiang Chen, Xi Chen, Xingyu Gao
Due to lack of inexpensive infrastructure rural communities suffer from inadequate Internet access, which is gradually widening the digital division between town and countryside, resulting in degrading both social communication and business advancements. In order to examine the feasibility of constructing a community mesh network using partial off-the-shelf hardware and software components, our research group has designed and deployed a Chinese social community network in the rural village of Beijing suburb for near one year, and then we propose a Pseudo-TDMA (PTDMA) controlled access protocol over EDCA function, which has an obvious saturation throughput improvement over existing IEEE 802.11e EDCA function when the packet size is big enough. The whole project provides the community with stable access services according to sharing a more expensive and high-speed Internet connections, and also presents an actual testbed to explore and solve key techniques and practical issues.
{"title":"Deploying a social community network in rural areas based on wireless mesh networks","authors":"Zhenyu Chen, Jingye Zhou, Yiqiang Chen, Xi Chen, Xingyu Gao","doi":"10.1109/YCICT.2009.5382320","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382320","url":null,"abstract":"Due to lack of inexpensive infrastructure rural communities suffer from inadequate Internet access, which is gradually widening the digital division between town and countryside, resulting in degrading both social communication and business advancements. In order to examine the feasibility of constructing a community mesh network using partial off-the-shelf hardware and software components, our research group has designed and deployed a Chinese social community network in the rural village of Beijing suburb for near one year, and then we propose a Pseudo-TDMA (PTDMA) controlled access protocol over EDCA function, which has an obvious saturation throughput improvement over existing IEEE 802.11e EDCA function when the packet size is big enough. The whole project provides the community with stable access services according to sharing a more expensive and high-speed Internet connections, and also presents an actual testbed to explore and solve key techniques and practical issues.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"207 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133928582","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382390
Xuesen Lin
A classic Finite State Machine (FSM) is a model of behavior composed of a finite number of states, transitions between those states, and actions. However, there are some cases where two or more behaviors are contained in one FSM, which is referred as MULTI-BEHAVIORS FINITE STATE MACHINE (MFSM) in this paper. Among these behaviors, some of their states differ from each other while others don't. How to distinct those differences as well as to keep and take advantage of their similarities would be a key to the management of this special type of Finite State Machine. This paper presents you some of the core characteristics of a MFSM at first, and then illustrates the practical implementation. In addition, some engineering experiences gained from real practices are provided.
{"title":"Multi-behaviors Finite State Machine","authors":"Xuesen Lin","doi":"10.1109/YCICT.2009.5382390","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382390","url":null,"abstract":"A classic Finite State Machine (FSM) is a model of behavior composed of a finite number of states, transitions between those states, and actions. However, there are some cases where two or more behaviors are contained in one FSM, which is referred as MULTI-BEHAVIORS FINITE STATE MACHINE (MFSM) in this paper. Among these behaviors, some of their states differ from each other while others don't. How to distinct those differences as well as to keep and take advantage of their similarities would be a key to the management of this special type of Finite State Machine. This paper presents you some of the core characteristics of a MFSM at first, and then illustrates the practical implementation. In addition, some engineering experiences gained from real practices are provided.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122327219","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382436
Sanbing Yang, Taijun Liu, Yan Ye, T. Xu
This paper presents a design approach of Doherty amplifier, which is based on optimizing the average power efficiency instead of peak power efficiency by adjusting the offset lines located in the branches of the carrier and the peak amplifier. The back-off point of the Doherty amplifier, which can be shifted by tuning the offset lines, should be optimized according to the power probability distribution of the modulated signal so as to achieve the maximum average power efficiency. A Doherty amplifier is designed using Freescale's MRF281S 4-W LDMOS FETs and the test signal is a TD-SCDMA signal at 2017.5MHz. The validation result of the Doherty amplifier show that the average power efficiency is 31.2 % at 9dB back-off point. The power efficiency enhances 4.2% and 3.9%, respectively, comparing with 27% at the 6dB back-off point and 27.3% at the 13 dB back-off point.
{"title":"Optium design of Doherty amplifiers based on average power efficiency","authors":"Sanbing Yang, Taijun Liu, Yan Ye, T. Xu","doi":"10.1109/YCICT.2009.5382436","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382436","url":null,"abstract":"This paper presents a design approach of Doherty amplifier, which is based on optimizing the average power efficiency instead of peak power efficiency by adjusting the offset lines located in the branches of the carrier and the peak amplifier. The back-off point of the Doherty amplifier, which can be shifted by tuning the offset lines, should be optimized according to the power probability distribution of the modulated signal so as to achieve the maximum average power efficiency. A Doherty amplifier is designed using Freescale's MRF281S 4-W LDMOS FETs and the test signal is a TD-SCDMA signal at 2017.5MHz. The validation result of the Doherty amplifier show that the average power efficiency is 31.2 % at 9dB back-off point. The power efficiency enhances 4.2% and 3.9%, respectively, comparing with 27% at the 6dB back-off point and 27.3% at the 13 dB back-off point.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125929696","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 : 2009-09-01DOI: 10.1109/YCICT.2009.5382361
Yang Li, Ning Zhang, Qiang Yang
Suffering from multiform time-variant and fluctuant clutter in High Frequency Radar(HFR), uniform target detection, tracking and clutter mitigation methods will result in false alarm or missing alarm. To select optimized detection and clutter mitigation method in the region of interesting, a method maximizing the separability of the resultant classes in amplitude of range-Doppler map is used for segmentation in multi-level detection background. Statistical and qualitative analysis is operated on the result of clutter extraction. Real data indicated that the proposed method can extract clutter region and adapt for various echo spectral maps for HFR as well, which can offer more accurate prior knowledge for target detection and clutter mitigation.
{"title":"Detection scene analysis for high frequency radar","authors":"Yang Li, Ning Zhang, Qiang Yang","doi":"10.1109/YCICT.2009.5382361","DOIUrl":"https://doi.org/10.1109/YCICT.2009.5382361","url":null,"abstract":"Suffering from multiform time-variant and fluctuant clutter in High Frequency Radar(HFR), uniform target detection, tracking and clutter mitigation methods will result in false alarm or missing alarm. To select optimized detection and clutter mitigation method in the region of interesting, a method maximizing the separability of the resultant classes in amplitude of range-Doppler map is used for segmentation in multi-level detection background. Statistical and qualitative analysis is operated on the result of clutter extraction. Real data indicated that the proposed method can extract clutter region and adapt for various echo spectral maps for HFR as well, which can offer more accurate prior knowledge for target detection and clutter mitigation.","PeriodicalId":138803,"journal":{"name":"2009 IEEE Youth Conference on Information, Computing and Telecommunication","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126354300","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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