Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689216
K. Hyun, D. Yoon, Ki Seol Kim, Lei Wang, Sang Kyu
In this paper, we present a simple and general bitwise decomposition expression using log likelihood ratio (LLR) of an arbitrary gray coded rectangular M-QAM signal. Based on the max-log MAP algorithm, we replace the mathematical max or min functions of the conventional LLR expression with simple arithmetic functions associated with given parameters such as a received symbol value and distance between symbols on a signal space. Since the derived LLR expression can be used as a soft bit metric for input to a conventional binary turbo decoder, it is suitable for practical applications with a turbo decoder or other related applications as an alternative to conventional methods
{"title":"Bitwise Decomposition of M-QAM Signals","authors":"K. Hyun, D. Yoon, Ki Seol Kim, Lei Wang, Sang Kyu","doi":"10.1109/ICICS.2005.1689216","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689216","url":null,"abstract":"In this paper, we present a simple and general bitwise decomposition expression using log likelihood ratio (LLR) of an arbitrary gray coded rectangular M-QAM signal. Based on the max-log MAP algorithm, we replace the mathematical max or min functions of the conventional LLR expression with simple arithmetic functions associated with given parameters such as a received symbol value and distance between symbols on a signal space. Since the derived LLR expression can be used as a soft bit metric for input to a conventional binary turbo decoder, it is suitable for practical applications with a turbo decoder or other related applications as an alternative to conventional methods","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133615114","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689249
Zhigang Zhou, Xiaodong Zhang
An improved channel estimator with time delay tracking measurement for OFDM systems is proposed by exploiting the inherent correlation between the cyclic prefix and port of the received OFDM signal. This scheme make use of real time measured size of inter-symbol interference (ISI) free window to estimate the maximum delay spread of channel, then a transform domain channel estimator is adopted to further reduce the noise variance. Due to the ISI-free window can be estimated before the application of FFT to the received signal, it is a parallel processing, and very suitable for the practical systems. Simulation result demonstrated that the proposed method can track the variation of delay spread of wireless channel, and improve the MSE of channel estimation significantly, thus give at least 1-dB improvement in ITU PA3 channel and 0.5-dB in ITU PB3 channel
利用接收OFDM信号的循环前缀和端口之间的固有相关性，提出了一种改进的OFDM信道估计器。该方案利用实时测量的无码间干扰(ISI)窗口的大小来估计信道的最大延迟扩展，然后采用变换域信道估计器进一步减小噪声方差。由于在FFT应用于接收信号之前可以估计出无is窗口，因此它是一种并行处理，非常适合于实际系统。仿真结果表明，该方法能够跟踪无线信道的延迟扩展变化，显著提高信道估计的MSE，在ITU PA3信道中至少提高1 db，在ITU PB3信道中至少提高0.5 db
{"title":"Channel Estimator with Time Spread Tracking for OFDM systems","authors":"Zhigang Zhou, Xiaodong Zhang","doi":"10.1109/ICICS.2005.1689249","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689249","url":null,"abstract":"An improved channel estimator with time delay tracking measurement for OFDM systems is proposed by exploiting the inherent correlation between the cyclic prefix and port of the received OFDM signal. This scheme make use of real time measured size of inter-symbol interference (ISI) free window to estimate the maximum delay spread of channel, then a transform domain channel estimator is adopted to further reduce the noise variance. Due to the ISI-free window can be estimated before the application of FFT to the received signal, it is a parallel processing, and very suitable for the practical systems. Simulation result demonstrated that the proposed method can track the variation of delay spread of wireless channel, and improve the MSE of channel estimation significantly, thus give at least 1-dB improvement in ITU PA3 channel and 0.5-dB in ITU PB3 channel","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"53 22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121162643","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689138
S. Luo, Li Zhang
Knowing the background model of a video scenario simplifies the problem of object segmentation and object tracking in the automated video surveillance applications. In this paper, a new algorithm for background model estimation was presented, which is useful in situations where an unobstructed view of the background is not always available. Discovering the true background interval in pixel's intensity history through local analysis of motion and spatial information, it avoids the problems of blending pixel values present in many current methods, such as mean filter and Kalman filter. Experimental results of applying our approach on a sequence of an indoor scene are provided to demonstrate the effectiveness of the proposed method
{"title":"A Background Model Estimation Algorithm Based on Analysis of Local Motion for Video Surveillance","authors":"S. Luo, Li Zhang","doi":"10.1109/ICICS.2005.1689138","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689138","url":null,"abstract":"Knowing the background model of a video scenario simplifies the problem of object segmentation and object tracking in the automated video surveillance applications. In this paper, a new algorithm for background model estimation was presented, which is useful in situations where an unobstructed view of the background is not always available. Discovering the true background interval in pixel's intensity history through local analysis of motion and spatial information, it avoids the problems of blending pixel values present in many current methods, such as mean filter and Kalman filter. Experimental results of applying our approach on a sequence of an indoor scene are provided to demonstrate the effectiveness of the proposed method","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116972632","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689272
J. Samuelsson
Gaussian mixture model (GMM) based vector quantization (VQ) using a data-dependent weighted Euclidean distortion measure is presented. It is shown how GMM-VQ can be improved by using GMMs that model the optimal VQ point density rather than the source probability density as is done in previous work. GMM training procedures as well as procedures for encoding and decoding that takes a weighted distortion measure into account are presented. The usefulness of the proposed procedures is demonstrated on a source derived from speech spectrum parameters
{"title":"Toward Optimal Mixture Model Based Vector Quantization","authors":"J. Samuelsson","doi":"10.1109/ICICS.2005.1689272","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689272","url":null,"abstract":"Gaussian mixture model (GMM) based vector quantization (VQ) using a data-dependent weighted Euclidean distortion measure is presented. It is shown how GMM-VQ can be improved by using GMMs that model the optimal VQ point density rather than the source probability density as is done in previous work. GMM training procedures as well as procedures for encoding and decoding that takes a weighted distortion measure into account are presented. The usefulness of the proposed procedures is demonstrated on a source derived from speech spectrum parameters","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117070738","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689039
Y. Yoon, Hyung-Myung Kim
The improper signals are often encountered in communications and signal processing. Since the known maximum-likelihood (ML) multiuser detection problem is only for proper noises, we derive the improper version of this expansion. We show that the proposed scheme improves the near-far resistance (NFR) for any spreading sequences and channel conditions. This gain comes from appropriate management of the additional information contained in nonzero pseudo-covariance matrix. The average NFR is obtained in a random channel environment and random spreading sequence. The proposed scheme halves the effective number of users. Although the ML multiuser detection gives us the optimum bit error rate (BER) performance, the computational complexity that is exponential in the number of users makes it impractical. In this paper, an efficient ML multiuser detection is developed. First, we relieve the combinatorial constraint of ML detection and obtain the initial decision of the symbols. Then, the most error probable symbols are chosen by referring the reliability measures of the initial symbols. The ML searching is accomplished with only the chosen symbols. Computer simulations demonstrate the results of the paper and show the error rate performance of the proposed near-ML multiuser detection
{"title":"Maximum Likelihood Multiuser Detection of DS/CDMA Signals in Improper Noiset","authors":"Y. Yoon, Hyung-Myung Kim","doi":"10.1109/ICICS.2005.1689039","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689039","url":null,"abstract":"The improper signals are often encountered in communications and signal processing. Since the known maximum-likelihood (ML) multiuser detection problem is only for proper noises, we derive the improper version of this expansion. We show that the proposed scheme improves the near-far resistance (NFR) for any spreading sequences and channel conditions. This gain comes from appropriate management of the additional information contained in nonzero pseudo-covariance matrix. The average NFR is obtained in a random channel environment and random spreading sequence. The proposed scheme halves the effective number of users. Although the ML multiuser detection gives us the optimum bit error rate (BER) performance, the computational complexity that is exponential in the number of users makes it impractical. In this paper, an efficient ML multiuser detection is developed. First, we relieve the combinatorial constraint of ML detection and obtain the initial decision of the symbols. Then, the most error probable symbols are chosen by referring the reliability measures of the initial symbols. The ML searching is accomplished with only the chosen symbols. Computer simulations demonstrate the results of the paper and show the error rate performance of the proposed near-ML multiuser detection","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115419779","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689271
Y. Chong, Liang Wang, S. Ting, W. Gan
An integrated approach towards the development of an active noise control (ANC) headset for audio and communication applications is explored and evaluated. Two different ANC methods are presented and their performance compared. The first method called the integrated feedback active noise control (IFBANC) system employs adaptive feedback ANC technique. Its main advantage is the use of a single error microphone per ear-cup. The second method is the integrated hybrid active noise control (IHANC) system. This approach combines adaptive feedforward and feedback ANC techniques and requires the use of an error microphone and a reference microphone that is mounted on the external of the ear-cup. Simulations have been conducted for both integrated ANC methods and they performed equally well in the lower frequency range. However, the IHANC system continues to perform moderately well in the mid frequency range where the IFBANC system exhibits only slight attenuation. In addition, the IHANC system performs better than the IFBANC system in attenuating narrowly spaced periodic noise in the lower frequency range
{"title":"Integrated Headsets Using the Adaptive Hybrid Active Noise Control System","authors":"Y. Chong, Liang Wang, S. Ting, W. Gan","doi":"10.1109/ICICS.2005.1689271","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689271","url":null,"abstract":"An integrated approach towards the development of an active noise control (ANC) headset for audio and communication applications is explored and evaluated. Two different ANC methods are presented and their performance compared. The first method called the integrated feedback active noise control (IFBANC) system employs adaptive feedback ANC technique. Its main advantage is the use of a single error microphone per ear-cup. The second method is the integrated hybrid active noise control (IHANC) system. This approach combines adaptive feedforward and feedback ANC techniques and requires the use of an error microphone and a reference microphone that is mounted on the external of the ear-cup. Simulations have been conducted for both integrated ANC methods and they performed equally well in the lower frequency range. However, the IHANC system continues to perform moderately well in the mid frequency range where the IFBANC system exhibits only slight attenuation. In addition, the IHANC system performs better than the IFBANC system in attenuating narrowly spaced periodic noise in the lower frequency range","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115422971","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689227
M. Niimi, H. Noda, B. Segee
This paper discusses a visual attack to BPCS-Steganography (Bit-Plane Complexity Segmentation-Steganography) and presents a countermeasure. BPCS categorizes each small block within cover images into either a "noise-like region" or an "informative region" by means of the binary-image feature called complexity and replaces noisy blocks with the binary patterns mapped from the bit sequences of secret data. The binary patterns must be complex because it is replacing complex regions. If the binary patterns to be inserted are simple, then the logical operation called conjugate operation is applied that transforms a simple pattern to a complex pattern. We need to keep, for each block, the flag called a conjugation flag representing whether or not conjugation had been applied to correctly extract the embedded information. In the case where the conjugation flags must be embedded within cover images, we are unable to use the complexity thresholding for the embedding of the flags. Thus the flags must be embedded into a fixed area. To this effect it is easy to recognize unnatural patterns on the LSB plane of stego-images. It can be used as a signature or a distinguishing mark between natural images and images with information embedded by BPCS. We propose secure BPCS which is robust against the visual attack. It is realized by assigning the meaning of the conjugation flag to a pixel of each block and making the specific rule to embed and extract it
{"title":"A Robust BPCS-Steganography against the Visual Attack","authors":"M. Niimi, H. Noda, B. Segee","doi":"10.1109/ICICS.2005.1689227","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689227","url":null,"abstract":"This paper discusses a visual attack to BPCS-Steganography (Bit-Plane Complexity Segmentation-Steganography) and presents a countermeasure. BPCS categorizes each small block within cover images into either a \"noise-like region\" or an \"informative region\" by means of the binary-image feature called complexity and replaces noisy blocks with the binary patterns mapped from the bit sequences of secret data. The binary patterns must be complex because it is replacing complex regions. If the binary patterns to be inserted are simple, then the logical operation called conjugate operation is applied that transforms a simple pattern to a complex pattern. We need to keep, for each block, the flag called a conjugation flag representing whether or not conjugation had been applied to correctly extract the embedded information. In the case where the conjugation flags must be embedded within cover images, we are unable to use the complexity thresholding for the embedding of the flags. Thus the flags must be embedded into a fixed area. To this effect it is easy to recognize unnatural patterns on the LSB plane of stego-images. It can be used as a signature or a distinguishing mark between natural images and images with information embedded by BPCS. We propose secure BPCS which is robust against the visual attack. It is realized by assigning the meaning of the conjugation flag to a pixel of each block and making the specific rule to embed and extract it","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115281853","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689108
T. Deng
We have theoretically proved the Liu-Wei's closed-form formula for computing the coefficients of one-dimensional (1-D) variable fractional-delay (VFD) finite-impulse-response (FIR) digital filter derived from nonlinear interpolating polynomial. In this paper, we reveal the symmetry of the VFD filter coefficients and exploit the coefficient symmetry in evaluating the VFD filter frequency characteristics with reduced computational complexity. The coefficient symmetry is also exploited in efficiently implementing the VFD filter as Farrow structure and even-odd structure for high-speed signal processing
{"title":"Coefficient Symmetry and Efficient Implementation of Lagrange-Type Variable Fractional-Delay Filters","authors":"T. Deng","doi":"10.1109/ICICS.2005.1689108","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689108","url":null,"abstract":"We have theoretically proved the Liu-Wei's closed-form formula for computing the coefficients of one-dimensional (1-D) variable fractional-delay (VFD) finite-impulse-response (FIR) digital filter derived from nonlinear interpolating polynomial. In this paper, we reveal the symmetry of the VFD filter coefficients and exploit the coefficient symmetry in evaluating the VFD filter frequency characteristics with reduced computational complexity. The coefficient symmetry is also exploited in efficiently implementing the VFD filter as Farrow structure and even-odd structure for high-speed signal processing","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116085406","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689186
Ducpyo Hong, Jinmok Lee, Jaeho Choi
This paper deals with the monitoring of power quality (PQ) variations continuously using power line communication (PLC). The power quality monitoring (PQM) has some merits to send and receive the PQ information without any new network lines as usual as in LAN communication. The PLC hardware and software techniques for PQM that meets the categories of IEEE Std. 1159 are described in this paper with some experimental results and also, this research shows that this system can be effectively applied for the power management of end user
{"title":"Power Quality Monitoring System Using Power Line Communication","authors":"Ducpyo Hong, Jinmok Lee, Jaeho Choi","doi":"10.1109/ICICS.2005.1689186","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689186","url":null,"abstract":"This paper deals with the monitoring of power quality (PQ) variations continuously using power line communication (PLC). The power quality monitoring (PQM) has some merits to send and receive the PQ information without any new network lines as usual as in LAN communication. The PLC hardware and software techniques for PQM that meets the categories of IEEE Std. 1159 are described in this paper with some experimental results and also, this research shows that this system can be effectively applied for the power management of end user","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116804154","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 : 2005-12-06DOI: 10.1109/ICICS.2005.1689244
Xiao liu, N. Saberi, Mark J. Coates, Lorne G. Mason
The internal switches in all-photonic networks do not perform data conversion into the electronic domain. Although this removal of O-E-O conversion eliminates a potential capacity bottleneck, it also introduces scheduling challenges; photonic switches cannot perform queuing operations, so traffic arrivals at these switches must be carefully scheduled. The (overlaid) star topology is an excellent match for an all-photonic network because it simplifies the scheduling problem. In such a network architecture, optical time division multiplexing (OTDM) approaches for scheduling the state of the central switch in the star are attractive. In this paper, we describe two OTDM algorithms that we have recently developed, one that performs scheduling on a slot-by-slot basis and another that schedules frames of multiple slots. We report and analyze the results of OPNET simulations that compare the performance of these scheduling algorithms
{"title":"A Comparison between Tnime-slot Scheduling Approaches for All-Photonic Networks","authors":"Xiao liu, N. Saberi, Mark J. Coates, Lorne G. Mason","doi":"10.1109/ICICS.2005.1689244","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689244","url":null,"abstract":"The internal switches in all-photonic networks do not perform data conversion into the electronic domain. Although this removal of O-E-O conversion eliminates a potential capacity bottleneck, it also introduces scheduling challenges; photonic switches cannot perform queuing operations, so traffic arrivals at these switches must be carefully scheduled. The (overlaid) star topology is an excellent match for an all-photonic network because it simplifies the scheduling problem. In such a network architecture, optical time division multiplexing (OTDM) approaches for scheduling the state of the central switch in the star are attractive. In this paper, we describe two OTDM algorithms that we have recently developed, one that performs scheduling on a slot-by-slot basis and another that schedules frames of multiple slots. We report and analyze the results of OPNET simulations that compare the performance of these scheduling algorithms","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123983229","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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