Pub Date : 2007-12-15DOI: 10.1109/ISSPIT.2007.4458002
C. Makassikis, S. Vialle, X. Warin
This paper introduces a research project that aims to speed-up and size-up some gas storage valuations, based on a Stochastic Dynamic Programming algorithm. Such valuations are typically needed by investment projects and yield prices of gas storage spaces and facilities. However, they involve computations which require great amounts of CPU power or memory. As a result, their parallelization on PC clusters or supercomputers becomes highly attractive and sometimes unavoidable despite its complexity. Our parallelization strategy is based on a message passing paradigm, and distributes both computations and data on a cluster, in order to achieve speed-up and size-up. It includes some complex and optimized data exchanges which are dynamically computed, planned and achieved at each computation step. This optimized data distribution and memory management allows to process large problems on a high number of processors. Moreover, our parallel implementation is able to support different price models, and our first experiments on a standard 32 PC cluster show very good performances particularly for complex price models.
{"title":"Distribution of a Stochastic Control Algorithm Applied to Gas Storage Valuation","authors":"C. Makassikis, S. Vialle, X. Warin","doi":"10.1109/ISSPIT.2007.4458002","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458002","url":null,"abstract":"This paper introduces a research project that aims to speed-up and size-up some gas storage valuations, based on a Stochastic Dynamic Programming algorithm. Such valuations are typically needed by investment projects and yield prices of gas storage spaces and facilities. However, they involve computations which require great amounts of CPU power or memory. As a result, their parallelization on PC clusters or supercomputers becomes highly attractive and sometimes unavoidable despite its complexity. Our parallelization strategy is based on a message passing paradigm, and distributes both computations and data on a cluster, in order to achieve speed-up and size-up. It includes some complex and optimized data exchanges which are dynamically computed, planned and achieved at each computation step. This optimized data distribution and memory management allows to process large problems on a high number of processors. Moreover, our parallel implementation is able to support different price models, and our first experiments on a standard 32 PC cluster show very good performances particularly for complex price models.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131370037","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458150
N. Kalantari, S. Ahadi, A. Kashi
In this paper, we present a mean quantization based audio watermarking scheme in the wavelet transform domain. The watermark data was embedded by quantizing the means of two selected bands of the wavelet transform of the original audio signal. One of the bands was in the lower frequency and the other one in the higher frequency ranges. Adaptive step sizes were used to achieve robustness and good transparency. As a result of selecting high and low frequency bands, this scheme is robust to both high- pass and low-pass attacks. The decoder detects the watermark data without any need to the original signal. The simulation results show that this watermarking scheme performs better than many recently proposed methods regarding robustness against common attacks such as MP3 compression, adding white Gaussian noise, filtering, resampling, etc.
{"title":"A Robust Audio Watermarking Scheme Using Mean Quantization in the Wavelet Transform Domain","authors":"N. Kalantari, S. Ahadi, A. Kashi","doi":"10.1109/ISSPIT.2007.4458150","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458150","url":null,"abstract":"In this paper, we present a mean quantization based audio watermarking scheme in the wavelet transform domain. The watermark data was embedded by quantizing the means of two selected bands of the wavelet transform of the original audio signal. One of the bands was in the lower frequency and the other one in the higher frequency ranges. Adaptive step sizes were used to achieve robustness and good transparency. As a result of selecting high and low frequency bands, this scheme is robust to both high- pass and low-pass attacks. The decoder detects the watermark data without any need to the original signal. The simulation results show that this watermarking scheme performs better than many recently proposed methods regarding robustness against common attacks such as MP3 compression, adding white Gaussian noise, filtering, resampling, etc.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"463 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123098694","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458173
E. Hoff, L. Brechtel, G. Barwolff, N. Natho, O. Pfeiffer, S. Jeschke
By means of 31P nuclear magnetic resonance (NMR) spectroscopy, metabolic conditions and changes in the resting and moving (human) musculature can be measured. Applications range from the examination of myopathies to the analysis of the composition of muscle fibers of competitive athletes. A vast amount of measurements of human skeletal muscles acquired using the 31P-NMR spectroscopy is waiting at hand to be processed. As manual processing of a single spectrum requires about half an hour of work form an exercised human analyzer several man-years of work are needed to do the job. Therefore a concept for the automatic post-processing of data acquired by 31P- NMR spectroscopy is presented.
{"title":"A concept of mathematical methods for the optimization of the post-processing of nuclear resonance spectra of the human skeletal musculature","authors":"E. Hoff, L. Brechtel, G. Barwolff, N. Natho, O. Pfeiffer, S. Jeschke","doi":"10.1109/ISSPIT.2007.4458173","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458173","url":null,"abstract":"By means of 31P nuclear magnetic resonance (NMR) spectroscopy, metabolic conditions and changes in the resting and moving (human) musculature can be measured. Applications range from the examination of myopathies to the analysis of the composition of muscle fibers of competitive athletes. A vast amount of measurements of human skeletal muscles acquired using the 31P-NMR spectroscopy is waiting at hand to be processed. As manual processing of a single spectrum requires about half an hour of work form an exercised human analyzer several man-years of work are needed to do the job. Therefore a concept for the automatic post-processing of data acquired by 31P- NMR spectroscopy is presented.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"2013 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114441765","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458074
Guilin Mal, F. Agerkvist, Jim Benjamin Luther2
This paper presents a two-stage approach for single- channel separation of dependent audio sources. The proposed algorithm is developed in the Bayesian framework and designed for general audio signals. In the first stage of the algorithm, the joint distribution of discrete Fourier transform (DFT) coefficients of the dependent sources is modeled by complex Gaussian mixture models in the frequency domain from samples of individual sources to capture the properties of the sources and their correlation. During the second stage, the mixture is separated through a generalized Wiener filter, which takes correlation term and local stationarity into account. The performance of the algorithm is tested on real audio signals. The results show that the proposed algorithm works very well when the dependent sources have comparable variances and linear correlation.
{"title":"Monaural Separation of Dependent Audio Sources Based on a Generalized Wiener Filter","authors":"Guilin Mal, F. Agerkvist, Jim Benjamin Luther2","doi":"10.1109/ISSPIT.2007.4458074","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458074","url":null,"abstract":"This paper presents a two-stage approach for single- channel separation of dependent audio sources. The proposed algorithm is developed in the Bayesian framework and designed for general audio signals. In the first stage of the algorithm, the joint distribution of discrete Fourier transform (DFT) coefficients of the dependent sources is modeled by complex Gaussian mixture models in the frequency domain from samples of individual sources to capture the properties of the sources and their correlation. During the second stage, the mixture is separated through a generalized Wiener filter, which takes correlation term and local stationarity into account. The performance of the algorithm is tested on real audio signals. The results show that the proposed algorithm works very well when the dependent sources have comparable variances and linear correlation.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127666333","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458040
M. Maamoun, A. Benbelkacem, D. Berkani
This paper describes the Second-order Extended Physical Addressing bus transactions between the microprocessor- based systems and the external peripherals. This addressing technique, based on the use of software/hardware systems and reduced physical addresses, enlarges the interfacing capacity of the microprocessor-based systems. The input of our system hardware part will be connected to the system bus. The output, which is a new bus, will be connected to an external device. To accomplish the bus transactions, the hardware part realizes a conversion of system bus data into new bus addresses. Furthermore, the software part ensures the transfer, with distinct addresses, of the simple data and the data that is intended to be converted. The use of this system with three system addresses and N bit data bus gives a new bus with N bit data bus and 22N physical addressing capacity.
{"title":"Bus Transactions in Microprocessor-based Systems using the Second-order Extened Physical Addressing","authors":"M. Maamoun, A. Benbelkacem, D. Berkani","doi":"10.1109/ISSPIT.2007.4458040","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458040","url":null,"abstract":"This paper describes the Second-order Extended Physical Addressing bus transactions between the microprocessor- based systems and the external peripherals. This addressing technique, based on the use of software/hardware systems and reduced physical addresses, enlarges the interfacing capacity of the microprocessor-based systems. The input of our system hardware part will be connected to the system bus. The output, which is a new bus, will be connected to an external device. To accomplish the bus transactions, the hardware part realizes a conversion of system bus data into new bus addresses. Furthermore, the software part ensures the transfer, with distinct addresses, of the simple data and the data that is intended to be converted. The use of this system with three system addresses and N bit data bus gives a new bus with N bit data bus and 22N physical addressing capacity.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115951256","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4457994
S. Choudhury, S. Ponda, J. Debnath, N. Debnath
In this paper, an exact analytical model for computation of burst length distribution under time-correlated input sources, at the output of an edge optical burst switching node, has been developed. Approximation techniques, to reduce time complexity of the model, have also been suggested. Effects of time correlation is successfully captured and it is found that for constant load, the variance of burst length increases with increased correlation. It is also observed that the variance of burst length reaches its peak value for a particular value of load, depending on the source correlation. The analytical results were verified with simulation studies.
{"title":"Effect of Time Correlation of Sources at the Output of Time Based Burst Assembler in Optical Burst Switched Network","authors":"S. Choudhury, S. Ponda, J. Debnath, N. Debnath","doi":"10.1109/ISSPIT.2007.4457994","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4457994","url":null,"abstract":"In this paper, an exact analytical model for computation of burst length distribution under time-correlated input sources, at the output of an edge optical burst switching node, has been developed. Approximation techniques, to reduce time complexity of the model, have also been suggested. Effects of time correlation is successfully captured and it is found that for constant load, the variance of burst length increases with increased correlation. It is also observed that the variance of burst length reaches its peak value for a particular value of load, depending on the source correlation. The analytical results were verified with simulation studies.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134381068","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458194
Ahmad Delforouzil, M. Pooyan
This paper presents a novel audio watermarking scheme based on echo hiding technique. This method is different from conventional echo hiding methods which embed only one bit in each audio section. In this method by using different echo delays we can embed more than one bit in each audio sections. For enhancing robustness of proposed algorithm against various types of attacks, we exploit dual echo kernels. Experimental results show that proposed method has good performance in robustness and inaudibility point of view.
{"title":"Increasing Payload of Echo Hiding Scheme Using Dual Backward and Forward Delay Kernels","authors":"Ahmad Delforouzil, M. Pooyan","doi":"10.1109/ISSPIT.2007.4458194","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458194","url":null,"abstract":"This paper presents a novel audio watermarking scheme based on echo hiding technique. This method is different from conventional echo hiding methods which embed only one bit in each audio section. In this method by using different echo delays we can embed more than one bit in each audio sections. For enhancing robustness of proposed algorithm against various types of attacks, we exploit dual echo kernels. Experimental results show that proposed method has good performance in robustness and inaudibility point of view.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131623567","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458109
H. Abdallah, I. Ghaleb, S. A. Chahine
The Bell Labs layered space-time (V-BLAST) algorithm is a promising multiple-input multiple-output (MIMO) transmission scheme. It attempts to utilize the high capacity of a MIMO system while maintaining low complexity. While no channel knowledge is required at the transmitter, accurate estimates of the channel are necessary at the receiver. The objective of this paper is to simulate numerically the wireless channel and the V-BLAST architecture to compare the performance of zero forcing (ZF) and a mean squared error (MMSE) receivers using linear nulling and symbol cancellation under imperfect channel state information (CSI). The simulation will compute the bit error rate for different values of SNR in a flat fading channel under imperfect channel estimation. The transmitted symbols will be modulated using a QPSK constellation. The results will be compared to those simulated using pilot estimation.
{"title":"The Effect of Imperfect Channel Estimation on the Performance of Layered Space Time Receivers","authors":"H. Abdallah, I. Ghaleb, S. A. Chahine","doi":"10.1109/ISSPIT.2007.4458109","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458109","url":null,"abstract":"The Bell Labs layered space-time (V-BLAST) algorithm is a promising multiple-input multiple-output (MIMO) transmission scheme. It attempts to utilize the high capacity of a MIMO system while maintaining low complexity. While no channel knowledge is required at the transmitter, accurate estimates of the channel are necessary at the receiver. The objective of this paper is to simulate numerically the wireless channel and the V-BLAST architecture to compare the performance of zero forcing (ZF) and a mean squared error (MMSE) receivers using linear nulling and symbol cancellation under imperfect channel state information (CSI). The simulation will compute the bit error rate for different values of SNR in a flat fading channel under imperfect channel estimation. The transmitted symbols will be modulated using a QPSK constellation. The results will be compared to those simulated using pilot estimation.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129397105","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 : 2007-12-01DOI: 10.1093/ietfec/e91-a.10.2990
Changhyeon Chae, Daewon Choi, T. Jung
In this paper, a new full-rate space-time block code (STBC) possessing a quasi-orthogonal (QO) property is proposed for QAM and 8 transmit antennas. This code is designed by serially concatenating a real constellation-rotating precoder with the Alamouti scheme. The QO property enables a maximum likelihood (ML) decoding to only require joint detection of four groups of real symbols at a receiver. Hence, this code has an identical and greatly reduced ML decoding complexity with the conventional minimum decoding complexity QO-STBC (MDC- QO-STBC) and the Xian's QO-STBC, respectively. Especially, the proposed QO-STBC is guaranteed to enjoy full diversity for general QAM unlike the existing MDC-QO-STBC presented for only QPSK. By simulation results, we show that the proposed code exhibits the identical and slightly degrade error performance with the existing MDC-QO-STBC for 4-QAM and the Xian's QO-STBC for 4 and 16-QAM, respectively.
{"title":"Design of New Minimum Decoding Complexity Quasi-Orthogonal Space-Time Block Code for 8 Transmit Antennas","authors":"Changhyeon Chae, Daewon Choi, T. Jung","doi":"10.1093/ietfec/e91-a.10.2990","DOIUrl":"https://doi.org/10.1093/ietfec/e91-a.10.2990","url":null,"abstract":"In this paper, a new full-rate space-time block code (STBC) possessing a quasi-orthogonal (QO) property is proposed for QAM and 8 transmit antennas. This code is designed by serially concatenating a real constellation-rotating precoder with the Alamouti scheme. The QO property enables a maximum likelihood (ML) decoding to only require joint detection of four groups of real symbols at a receiver. Hence, this code has an identical and greatly reduced ML decoding complexity with the conventional minimum decoding complexity QO-STBC (MDC- QO-STBC) and the Xian's QO-STBC, respectively. Especially, the proposed QO-STBC is guaranteed to enjoy full diversity for general QAM unlike the existing MDC-QO-STBC presented for only QPSK. By simulation results, we show that the proposed code exhibits the identical and slightly degrade error performance with the existing MDC-QO-STBC for 4-QAM and the Xian's QO-STBC for 4 and 16-QAM, respectively.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133444452","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 : 2007-12-01DOI: 10.1109/ISSPIT.2007.4458106
S. Chan, Y. Zhou
This paper studies the convergence behaviors of the normalized least mean square (NLMS) and the normalized least mean M-estimate (NLMM) algorithms. Our analysis is obtained by extending the framework of Bershad [6], [7], which were previously reported for the NLMS algorithm with Gaussian inputs. Due to the difficulties in evaluating certain expectations involved, in [6], [7] the behaviors of the NLMS algorithm for general eigenvalue distributions of input autocorrelation matrix were not fully analyzed. In this paper, using an extension of Price's theorem to mixture Gaussian distributions and by introducing certain special integral functions, closed-form results of these expectations are obtained which allow us to interpret the convergence performance of both the NLMS and the NLMM algorithms in Contaminated Gaussian noise. The validity of the proposed analysis is verified through computer simulations.
{"title":"On the Convergence Analysis of the Normalized LMS and the Normalized Least Mean M-Estimate Algorithms","authors":"S. Chan, Y. Zhou","doi":"10.1109/ISSPIT.2007.4458106","DOIUrl":"https://doi.org/10.1109/ISSPIT.2007.4458106","url":null,"abstract":"This paper studies the convergence behaviors of the normalized least mean square (NLMS) and the normalized least mean M-estimate (NLMM) algorithms. Our analysis is obtained by extending the framework of Bershad [6], [7], which were previously reported for the NLMS algorithm with Gaussian inputs. Due to the difficulties in evaluating certain expectations involved, in [6], [7] the behaviors of the NLMS algorithm for general eigenvalue distributions of input autocorrelation matrix were not fully analyzed. In this paper, using an extension of Price's theorem to mixture Gaussian distributions and by introducing certain special integral functions, closed-form results of these expectations are obtained which allow us to interpret the convergence performance of both the NLMS and the NLMM algorithms in Contaminated Gaussian noise. The validity of the proposed analysis is verified through computer simulations.","PeriodicalId":299267,"journal":{"name":"2007 IEEE International Symposium on Signal Processing and Information Technology","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133454134","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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