Pub Date : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577139
J. D. Chimeh, H. Bakhshi, E. Karami
In this paper, a semi-blind beamforming algorithm is proposed for Orthogonal Frequency Division Multiplexing (OFDM) signals to combat multipath fading which is based on semi-blind beamforming of each sub-band in a OFDM system using Decision Directed Algorithm (DDA). The proposed algorithm is simulated for time varying channel with Clark model for block to block variation of the channel coefficients it is shown that without semi-blind operation error floor occurs in the performance of the sub-band beamformer but in the blind mode of the operation, by exploiting the information contents in the decisions the sub-band beamformer provides efficient bit error rate versus 0 / N Eb even in different block length and
针对正交频分复用(OFDM)信号的多径衰落问题，提出了一种基于决策定向算法(DDA)对OFDM系统各子带进行半盲波束形成的半盲波束形成算法。采用Clark模型对时变信道进行了信道系数块对块变化的仿真，结果表明，在半盲工作时，子带波束形成器的性能会出现误差层，但在盲工作模式下，通过利用决策中的信息内容，子带波束形成器即使在不同的块长度和带宽下也能提供相对于0 / N Eb的有效误码率
{"title":"Sub-band beamforming of OFDM signals in time varying multi-path fading channel","authors":"J. D. Chimeh, H. Bakhshi, E. Karami","doi":"10.1109/ISSPIT.2005.1577139","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577139","url":null,"abstract":"In this paper, a semi-blind beamforming algorithm is proposed for Orthogonal Frequency Division Multiplexing (OFDM) signals to combat multipath fading which is based on semi-blind beamforming of each sub-band in a OFDM system using Decision Directed Algorithm (DDA). The proposed algorithm is simulated for time varying channel with Clark model for block to block variation of the channel coefficients it is shown that without semi-blind operation error floor occurs in the performance of the sub-band beamformer but in the blind mode of the operation, by exploiting the information contents in the decisions the sub-band beamformer provides efficient bit error rate versus 0 / N Eb even in different block length and","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126336162","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577118
B. Sayadi, S. Ataman, I. Fijalkow
In this paper, we propose to combine the gains of a downlink power control and a joint multicode detection, for a HSDPA link. We propose an algorithm, which controls both the transmitted code powers and the joint multicode receiver filter coefficients. The proposed algorithm is iterative. At each iteration, first, the receiver filter coefficients of the multicode user are updated to reduce the inter-code interferences and then, the transmitted code powers are updated. So that, each spreading code of the multicode scheme creates the minimum possible interference to others while satisfying the quality of service requirement. This algorithm has as main goals to decrease inter-code interference and to increase the system capacity. Simulation is used to show the convergence of the proposed algorithm to a fixed point power vector where the multicode user satisfies its signal-to-interference ratio (SIR) target on each code
{"title":"Combined downlink power control and joint multicode receivers for downlink transmissions in high speed UMTS","authors":"B. Sayadi, S. Ataman, I. Fijalkow","doi":"10.1109/ISSPIT.2005.1577118","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577118","url":null,"abstract":"In this paper, we propose to combine the gains of a downlink power control and a joint multicode detection, for a HSDPA link. We propose an algorithm, which controls both the transmitted code powers and the joint multicode receiver filter coefficients. The proposed algorithm is iterative. At each iteration, first, the receiver filter coefficients of the multicode user are updated to reduce the inter-code interferences and then, the transmitted code powers are updated. So that, each spreading code of the multicode scheme creates the minimum possible interference to others while satisfying the quality of service requirement. This algorithm has as main goals to decrease inter-code interference and to increase the system capacity. Simulation is used to show the convergence of the proposed algorithm to a fixed point power vector where the multicode user satisfies its signal-to-interference ratio (SIR) target on each code","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"5 57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131264131","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577159
M. S. Yasein, P. Agathoklis
In this paper a new image registration algorithm is proposed. Rotation, translation, and scaling (RTS) transformations are considered in the registration process. The proposed algorithm consists of three main steps: extraction of some feature points using a robust feature points extractor based on scale-interaction of Mexican-hat wavelets, obtaining the correspondence between the features points of the reference and distorted images based on using Zernike moments of neighbourhoods centered on feature points, and estimating the transformation parameters mapping the distorted image to the reference one. Experimental results illustrate the registration accuracy of the proposed technique and its robustness against several common image-processing operations
{"title":"Automatic and robust image registration using feature points extraction and Zernike moments invariants","authors":"M. S. Yasein, P. Agathoklis","doi":"10.1109/ISSPIT.2005.1577159","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577159","url":null,"abstract":"In this paper a new image registration algorithm is proposed. Rotation, translation, and scaling (RTS) transformations are considered in the registration process. The proposed algorithm consists of three main steps: extraction of some feature points using a robust feature points extractor based on scale-interaction of Mexican-hat wavelets, obtaining the correspondence between the features points of the reference and distorted images based on using Zernike moments of neighbourhoods centered on feature points, and estimating the transformation parameters mapping the distorted image to the reference one. Experimental results illustrate the registration accuracy of the proposed technique and its robustness against several common image-processing operations","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114611029","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577196
F. Beritelli, S. Casale, S. Serrano
The paper presents an adaptive system for speech signal processing in the presence of loud background noise. The validity of the approach is confirmed by implementing a classification system for voiced and unvoiced (V/UV) speech frames. Genetic algorithms were used to select the parameters that offer the best V/UV classification in the presence of 4 different types of background noise and with 5 different SNRs. 20 neural network-based classification systems were then implemented, chosen dynamically frame by frame according to the output of a background noise recognition system and an SNR estimation system. The system was implemented and the tests performed using the TIMIT speech corpus and its phonetic classification. The results were compared with a non-adaptive classification system and the 3 V/UV detectors adopted by three important: LPClO, ITU-T G. 723.1 and ETSI AMR. In all cases the adaptive V/UV classifier clearly outperformed the others, confirming the validity of the adaptive approach
提出了一种适用于大背景噪声环境下语音信号处理的自适应系统。通过实现浊音和浊音(V/UV)语音帧的分类系统，验证了该方法的有效性。在4种不同类型的背景噪声和5种不同信噪比的情况下，使用遗传算法选择提供最佳V/UV分类的参数。然后实现了20个基于神经网络的分类系统，根据背景噪声识别系统和信噪比估计系统的输出逐帧动态选择。利用TIMIT语音语料库及其语音分类对系统进行了实现和测试。结果与非自适应分类系统和三种重要的3 V/UV检测器LPClO、ITU-T G. 723.1和ETSI AMR进行了比较。在所有情况下，自适应V/UV分类器明显优于其他分类器，证实了自适应方法的有效性
{"title":"Adaptive robust speech processing based on acoustic noise estimation and classification","authors":"F. Beritelli, S. Casale, S. Serrano","doi":"10.1109/ISSPIT.2005.1577196","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577196","url":null,"abstract":"The paper presents an adaptive system for speech signal processing in the presence of loud background noise. The validity of the approach is confirmed by implementing a classification system for voiced and unvoiced (V/UV) speech frames. Genetic algorithms were used to select the parameters that offer the best V/UV classification in the presence of 4 different types of background noise and with 5 different SNRs. 20 neural network-based classification systems were then implemented, chosen dynamically frame by frame according to the output of a background noise recognition system and an SNR estimation system. The system was implemented and the tests performed using the TIMIT speech corpus and its phonetic classification. The results were compared with a non-adaptive classification system and the 3 V/UV detectors adopted by three important: LPClO, ITU-T G. 723.1 and ETSI AMR. In all cases the adaptive V/UV classifier clearly outperformed the others, confirming the validity of the adaptive approach","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129239093","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577133
Liyu Liu, M. Amin
The performance of GPS delay lock loop (DLL) can be greatly compromised by multipath. This paper considers the effects of multipath on the GPS receiver. It evaluates the DLL performance in terms of the tracking error of the noncoherent early-minus-late power discriminator. We discuss the effect of precorrelation filter bandwidth on the autocorrelation function of the GPS spreading code and subsequently, on the DLL signal tracking. The tracking error, which is influenced by the precorrelation filter bandwidth, is analyzed
{"title":"Multipath and precorrelation filtering effect on GPS noncoherent early-minus-late power discriminators","authors":"Liyu Liu, M. Amin","doi":"10.1109/ISSPIT.2005.1577133","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577133","url":null,"abstract":"The performance of GPS delay lock loop (DLL) can be greatly compromised by multipath. This paper considers the effects of multipath on the GPS receiver. It evaluates the DLL performance in terms of the tracking error of the noncoherent early-minus-late power discriminator. We discuss the effect of precorrelation filter bandwidth on the autocorrelation function of the GPS spreading code and subsequently, on the DLL signal tracking. The tracking error, which is influenced by the precorrelation filter bandwidth, is analyzed","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"485 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133731102","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577131
M. Matsumoto, S. Hashimoto
This paper introduces the direction of arrival estimation by a power inversion adaptive array (PIAA) method that utilizes the transfer characteristics of microphones located at a same place, namely aggregated microphones. In this paper, we firstly show that the microphone array system and the proposed aggregated microphone system can be described in the same framework. We then apply the PIAA method to the aggregated microphones and compare the proposed method with the microphone array. In the proposed method, all microphones are placed at the same place. Hence, it is easy to miniaturize the system. This feature is considered to be useful in the practical applications. We show the directional pattern of the PIAA utilizing aggregated microphones. We also show the results of the DOA estimation
{"title":"DOA estimation utilizing power inversion adaptive array by aggregated microphones","authors":"M. Matsumoto, S. Hashimoto","doi":"10.1109/ISSPIT.2005.1577131","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577131","url":null,"abstract":"This paper introduces the direction of arrival estimation by a power inversion adaptive array (PIAA) method that utilizes the transfer characteristics of microphones located at a same place, namely aggregated microphones. In this paper, we firstly show that the microphone array system and the proposed aggregated microphone system can be described in the same framework. We then apply the PIAA method to the aggregated microphones and compare the proposed method with the microphone array. In the proposed method, all microphones are placed at the same place. Hence, it is easy to miniaturize the system. This feature is considered to be useful in the practical applications. We show the directional pattern of the PIAA utilizing aggregated microphones. We also show the results of the DOA estimation","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114896903","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577062
Jared C. Smolens, Jangwoo Kim, J. Hoe, B. Falsafi
Superscalar out-of-order micro architectures can be modified to support redundant execution of a program as two concurrent threads for soft-error detection. However, the extra workload from redundant execution incurs a performance penalty due to increased contention for resources throughout the datapath. We present four key parameters that affect performance of these designs, namely 1) issue and functional unit bandwidth, 2) issue queue and reorder buffer capacity, 3) decode and retirement bandwidth, and 4) coupling between redundant threads' instantaneous resource requirements. We then survey existing work in concurrent error detecting superscalar micro architectures and evaluate these proposals with respect to the four factors
{"title":"Understanding the performance of concurrent error detecting superscalar microarchitectures","authors":"Jared C. Smolens, Jangwoo Kim, J. Hoe, B. Falsafi","doi":"10.1109/ISSPIT.2005.1577062","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577062","url":null,"abstract":"Superscalar out-of-order micro architectures can be modified to support redundant execution of a program as two concurrent threads for soft-error detection. However, the extra workload from redundant execution incurs a performance penalty due to increased contention for resources throughout the datapath. We present four key parameters that affect performance of these designs, namely 1) issue and functional unit bandwidth, 2) issue queue and reorder buffer capacity, 3) decode and retirement bandwidth, and 4) coupling between redundant threads' instantaneous resource requirements. We then survey existing work in concurrent error detecting superscalar micro architectures and evaluate these proposals with respect to the four factors","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128638946","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577072
Ehab Y. Abdel Maksoud, Reda A. Ammar
In this paper, we present a new heuristic algorithm to schedule a set of independent stochastic tasks with parallelizable contents in multiprocessor systems. Each task is described by its deadline and its time cost distribution, which is given in terms of mean and variance. A scheduled task may run as one unit on a single processor or partitioned into k parallel parts running on k different processors. The proposed algorithm exploits parallelism in tasks, if it is necessary, and distributes them among the available processors to yield a high probability of meeting their deadlines and, hence obtain better schedulability
{"title":"Scheduling stochastic tasks with parallelizable contents in multiprocessor systems","authors":"Ehab Y. Abdel Maksoud, Reda A. Ammar","doi":"10.1109/ISSPIT.2005.1577072","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577072","url":null,"abstract":"In this paper, we present a new heuristic algorithm to schedule a set of independent stochastic tasks with parallelizable contents in multiprocessor systems. Each task is described by its deadline and its time cost distribution, which is given in terms of mean and variance. A scheduled task may run as one unit on a single processor or partitioned into k parallel parts running on k different processors. The proposed algorithm exploits parallelism in tasks, if it is necessary, and distributes them among the available processors to yield a high probability of meeting their deadlines and, hence obtain better schedulability","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133927730","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577081
H. T. Nguyen, G. Leus, N. Khaled
In mobile communications, time varying channels make the available channel information out of date. Timely updating the channel state is an obvious solution to improve the system performance in a time varying channel. However, a better knowledge of the channel comes at the cost of a decrease in the system throughput. Thus, predicting the future channel conditions can improve not only the performance but also the throughput of many types of wireless systems. This is especially true for a wireless system where multiple antennas are applied at both link ends. In this paper we propose and evaluate the performance of a prediction scheme for multiple input multiple output (MIMO) systems that apply spatial multiplexing. We aim at predicting the future precoder/decoder directly without going through the prediction of the channel matrix. The results show that in a slowly time varying channel an increase in the system performance by a factor of two is possible
{"title":"Prediction of the eigenvectors for spatial multiplexing MIMO systems in time-varying channels","authors":"H. T. Nguyen, G. Leus, N. Khaled","doi":"10.1109/ISSPIT.2005.1577081","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577081","url":null,"abstract":"In mobile communications, time varying channels make the available channel information out of date. Timely updating the channel state is an obvious solution to improve the system performance in a time varying channel. However, a better knowledge of the channel comes at the cost of a decrease in the system throughput. Thus, predicting the future channel conditions can improve not only the performance but also the throughput of many types of wireless systems. This is especially true for a wireless system where multiple antennas are applied at both link ends. In this paper we propose and evaluate the performance of a prediction scheme for multiple input multiple output (MIMO) systems that apply spatial multiplexing. We aim at predicting the future precoder/decoder directly without going through the prediction of the channel matrix. The results show that in a slowly time varying channel an increase in the system performance by a factor of two is possible","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"175 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131974612","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 : 2005-12-21DOI: 10.1109/ISSPIT.2005.1577084
A. Yildirim, M. Efe, A.K. Ozdemir
In this paper we analyze the peak picking losses induced by conventional radar signal processors, which assume a point target model for detection and tracking. As demonstrated through simulations, the performance degradation under the point target assumption can be significant for high-resolution radars, where targets extend across several detection cells. Interpolation of nearby data around the detected peak provides only a slight improvement. This paper presents a maximum likelihood estimator (MLE) to reduce the peak picking losses. By comparing the variance of the estimator with the Cramer Rao lower bound derived in this paper, it has been shown that the maximum likelihood estimator significantly reduces peak picking losses
{"title":"Peak picking losses in radar detectors","authors":"A. Yildirim, M. Efe, A.K. Ozdemir","doi":"10.1109/ISSPIT.2005.1577084","DOIUrl":"https://doi.org/10.1109/ISSPIT.2005.1577084","url":null,"abstract":"In this paper we analyze the peak picking losses induced by conventional radar signal processors, which assume a point target model for detection and tracking. As demonstrated through simulations, the performance degradation under the point target assumption can be significant for high-resolution radars, where targets extend across several detection cells. Interpolation of nearby data around the detected peak provides only a slight improvement. This paper presents a maximum likelihood estimator (MLE) to reduce the peak picking losses. By comparing the variance of the estimator with the Cramer Rao lower bound derived in this paper, it has been shown that the maximum likelihood estimator significantly reduces peak picking losses","PeriodicalId":421826,"journal":{"name":"Proceedings of the Fifth IEEE International Symposium on Signal Processing and Information Technology, 2005.","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133578309","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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