Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689209
S. Kandeepan, S. Reisenfeld
The treatment of phase locked loops (PLL) has been heavily looked into over the past several decades on its performances and analysis, and is a very old topic. However the usage of it has never been reduced with the rapid evolvement of various open loop and closed loop systems. In this paper we analyse the performance of an arctan based digital phase locked loop (DPLL) with a hyperbolic nonlinearity for single-tone carrier tracking. We purposely introduce the nonlinearity for improved performance of the closed loop system. We look at the acquisition performance of the DPLL by considering the phase plane portrait and the lock-in range of the loop. The steady state (SS) performance of the loop is analysed by considering the open loop SS statistical distribution of the phase noise
{"title":"Performance analysis of a Digital Phase-Locked Loop with a Hyperbolic Nonlinearity","authors":"S. Kandeepan, S. Reisenfeld","doi":"10.1109/ICICS.2005.1689209","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689209","url":null,"abstract":"The treatment of phase locked loops (PLL) has been heavily looked into over the past several decades on its performances and analysis, and is a very old topic. However the usage of it has never been reduced with the rapid evolvement of various open loop and closed loop systems. In this paper we analyse the performance of an arctan based digital phase locked loop (DPLL) with a hyperbolic nonlinearity for single-tone carrier tracking. We purposely introduce the nonlinearity for improved performance of the closed loop system. We look at the acquisition performance of the DPLL by considering the phase plane portrait and the lock-in range of the loop. The steady state (SS) performance of the loop is analysed by considering the open loop SS statistical distribution of the phase noise","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"3 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":"122370347","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.2005.1689111
S. Yimman, S. Praesomboon, S. Klunium, S. Navarattara, K. Dejhan
This paper proposes the new two-pole band-pass filter design principle for the all-pass filter and notch filter by applying the least square. The first step is to design notch filter by using pole-zero placement and then modify pole positions to control pass-band filter gain to ensure the symmetry with the maximum gain at the target level. After that, there is the design of all-pass filter with pole at the same positions as the notch filters to make the negative cascade with the designed notch filter to get the transfer function with band-pass filter magnitude response. The results from the experiments on MATLAB have shown the two-pole band-pass filter of the new design with the accurate and symmetric gain
{"title":"Two-Pole Band-pass Filter Based on All-pass Filter","authors":"S. Yimman, S. Praesomboon, S. Klunium, S. Navarattara, K. Dejhan","doi":"10.1109/ICICS.2005.1689111","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689111","url":null,"abstract":"This paper proposes the new two-pole band-pass filter design principle for the all-pass filter and notch filter by applying the least square. The first step is to design notch filter by using pole-zero placement and then modify pole positions to control pass-band filter gain to ensure the symmetry with the maximum gain at the target level. After that, there is the design of all-pass filter with pole at the same positions as the notch filters to make the negative cascade with the designed notch filter to get the transfer function with band-pass filter magnitude response. The results from the experiments on MATLAB have shown the two-pole band-pass filter of the new design with the accurate and symmetric gain","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"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":"122882881","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.2005.1689054
M. Mahfuz, K. Ahmed, R. Rajatheva
In high data rate indoor ultra wideband (UWB) communication systems, the selection of the appropriate detection method in the receiver is always an important problem. This paper compares the performances of two different detection methods, hard decision detection (HDD) and soft decision detection (SDD), for three different types of indoor UWB systems named time hopping pulse position modulation (TH-PPM), direct sequence bi-phase modulation (DS-BPM) and time hopping bi-phase modulation (TH-BPM) UWB indoor communication systems with multiple user interference (MUI). Using the recently accepted IEEE 802.15.3a UWB channel model, the three schemes were compared. Finally, it has been concluded that for both DS-BPM and TH-BPM systems, SDD outperforms HDD in terms of BER performance and so SDD should be chosen as the preferred detection scheme. However, in case of TH-PPM system, the system BER performance depends on the pulse repetition rate, any of SDD and HDD can be chosen as preferred detection scheme if one pulse per bit is used whereas for multiple pulses per bit SDD outperforms HDD significantly. Using SDD method, DS-BPM scheme can achieve the maximum SNR gain in presence of multiple user interference (MUI)
{"title":"On the Detection Methods for Indoor Ultra Wideband Communications with Multiple User Interference","authors":"M. Mahfuz, K. Ahmed, R. Rajatheva","doi":"10.1109/ICICS.2005.1689054","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689054","url":null,"abstract":"In high data rate indoor ultra wideband (UWB) communication systems, the selection of the appropriate detection method in the receiver is always an important problem. This paper compares the performances of two different detection methods, hard decision detection (HDD) and soft decision detection (SDD), for three different types of indoor UWB systems named time hopping pulse position modulation (TH-PPM), direct sequence bi-phase modulation (DS-BPM) and time hopping bi-phase modulation (TH-BPM) UWB indoor communication systems with multiple user interference (MUI). Using the recently accepted IEEE 802.15.3a UWB channel model, the three schemes were compared. Finally, it has been concluded that for both DS-BPM and TH-BPM systems, SDD outperforms HDD in terms of BER performance and so SDD should be chosen as the preferred detection scheme. However, in case of TH-PPM system, the system BER performance depends on the pulse repetition rate, any of SDD and HDD can be chosen as preferred detection scheme if one pulse per bit is used whereas for multiple pulses per bit SDD outperforms HDD significantly. Using SDD method, DS-BPM scheme can achieve the maximum SNR gain in presence of multiple user interference (MUI)","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"28 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":"116724771","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.2005.1689247
Yonghong Zeng, A. R. Leyman, Shaodan Ma, T. Ng
In this paper, a class of unitary transform based optimal pilots is found for time domain channel estimation in multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. Also, a frequency domain channel estimation which does not need interpolation is obtained. It is shown that the frequency domain method achieves the same performance as the time domain method and is better than interpolation methods. Furthermore, fast algorithms are proposed to implement the methods. Simulations demonstrate that the methods are effective
{"title":"Optimal Pilot and Fast Algorithm for MIMO-OFDM Channel Estimation","authors":"Yonghong Zeng, A. R. Leyman, Shaodan Ma, T. Ng","doi":"10.1109/ICICS.2005.1689247","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689247","url":null,"abstract":"In this paper, a class of unitary transform based optimal pilots is found for time domain channel estimation in multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. Also, a frequency domain channel estimation which does not need interpolation is obtained. It is shown that the frequency domain method achieves the same performance as the time domain method and is better than interpolation methods. Furthermore, fast algorithms are proposed to implement the methods. Simulations demonstrate that the methods are effective","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":"128272355","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.2005.1689312
Lau Chun Hau, B. Soong, S. Bose
In this paper, we study the effects of preemption and re-routing on the performance of multi protocol label switching (MPLS) networks. MPLS with traffic engineering supports diversified quality of service (QoS) requirements and allows the setting up of explicit path through networks. Usually, traffic engineering is used to achieve load balancing where longer path may be used to route a connection to prevent part of the network from over-utilized. However, since a longer path needs more resources, this may increase the loss probability of a network. This is especially true if the connection routed is of high priority which cannot be preempted by future connections. We suggest that a high priority connection should always be routed on the shortest path to minimize the consumption of network resources. Preemption may be triggered to acquire the resources needed from the existing lower priority connections. The connections to be preempted can be re-routed to avoid the interruption of service. We introduce a new strategy to preempt the existing connections and control the re-routing process to avoid the explosion of re-routing process for a single preemption event. Finally, the simulation results show that the new strategy can limit the extent of re-routing process and improve the network performance significantly
本文研究了抢占和重路由对多协议标签交换(MPLS)网络性能的影响。具有流量工程功能的MPLS支持多样化的QoS (quality of service)需求，允许在网络中建立显式路径。通常，流量工程用于实现负载均衡，可以使用较长的路径来路由连接，以防止部分网络被过度利用。但是，由于更长的路径需要更多的资源，这可能会增加网络的损失概率。如果路由的连接具有高优先级，不能被未来的连接抢占，则尤其如此。我们建议高优先级的连接应该始终在最短路径上路由，以尽量减少网络资源的消耗。可以触发抢占，从现有的低优先级连接中获取所需的资源。需要抢占的连接可以重新路由，避免业务中断。我们提出了一种新的策略来抢占现有连接并控制重路由过程，以避免单个抢占事件导致重路由过程爆炸。仿真结果表明，该策略能有效地限制重路由过程的范围，显著提高网络性能
{"title":"A New Preemption Strategy with Re-routing Control for MPLS Networks","authors":"Lau Chun Hau, B. Soong, S. Bose","doi":"10.1109/ICICS.2005.1689312","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689312","url":null,"abstract":"In this paper, we study the effects of preemption and re-routing on the performance of multi protocol label switching (MPLS) networks. MPLS with traffic engineering supports diversified quality of service (QoS) requirements and allows the setting up of explicit path through networks. Usually, traffic engineering is used to achieve load balancing where longer path may be used to route a connection to prevent part of the network from over-utilized. However, since a longer path needs more resources, this may increase the loss probability of a network. This is especially true if the connection routed is of high priority which cannot be preempted by future connections. We suggest that a high priority connection should always be routed on the shortest path to minimize the consumption of network resources. Preemption may be triggered to acquire the resources needed from the existing lower priority connections. The connections to be preempted can be re-routed to avoid the interruption of service. We introduce a new strategy to preempt the existing connections and control the re-routing process to avoid the explosion of re-routing process for a single preemption event. Finally, the simulation results show that the new strategy can limit the extent of re-routing process and improve the network performance significantly","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"23 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":"128285293","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.2005.1689041
L. Han, Zhengxin Ma, Hulling Zhu, Han Hu
The selection and collection of the node state information have great impact on the design complexity and performance of a QoS routing algorithm. Continuous-media traffic (e.g. audio and video) can tolerate some loss but has rigid delay constraints. Under this QoS constraint, the node-delay's probability density function (PDF) is used to character the node state. The continuous-media traffic is in high burst. So the node-delay's PDF is shaped into normal distribution through a filter algorithm. Analysis and simulation show that the tail probability of the normal distribution can be used to calculate the end-to-end packet loss rate approximately. Then the variance and mean value of the PDF can be controlled to calculate a proper packet loss rate to satisfy the QoS demand. So normal distribution is a simple, achievable and reasonable description
{"title":"Research on QoS-Based Networks Node-State","authors":"L. Han, Zhengxin Ma, Hulling Zhu, Han Hu","doi":"10.1109/ICICS.2005.1689041","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689041","url":null,"abstract":"The selection and collection of the node state information have great impact on the design complexity and performance of a QoS routing algorithm. Continuous-media traffic (e.g. audio and video) can tolerate some loss but has rigid delay constraints. Under this QoS constraint, the node-delay's probability density function (PDF) is used to character the node state. The continuous-media traffic is in high burst. So the node-delay's PDF is shaped into normal distribution through a filter algorithm. Analysis and simulation show that the tail probability of the normal distribution can be used to calculate the end-to-end packet loss rate approximately. Then the variance and mean value of the PDF can be controlled to calculate a proper packet loss rate to satisfy the QoS demand. So normal distribution is a simple, achievable and reasonable description","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"31 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":"124761149","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}
A periodic radial basis function (RBF) network is proposed based on the regularization approach. The periodic RBF network can interpolate discrete data more efficiently than the conventional one since the coefficients of the network can be computed by using the fast Fourier transform (FFT). For the evaluation of the interpolation capability, the frequency response of the periodic RBF network is analyzed. It is then shown that the frequency response is asymptotically equivalent to the ideal sine interpolation, and that the periodic RBF network is closer to the ideal sine interpolation than the cubic spline and Lanczos interpolations
{"title":"Interpolation capability of the periodic radial basis function","authors":"Y. Abe, Y. Iiguni","doi":"10.1049/IP-VIS:20050259","DOIUrl":"https://doi.org/10.1049/IP-VIS:20050259","url":null,"abstract":"A periodic radial basis function (RBF) network is proposed based on the regularization approach. The periodic RBF network can interpolate discrete data more efficiently than the conventional one since the coefficients of the network can be computed by using the fast Fourier transform (FFT). For the evaluation of the interpolation capability, the frequency response of the periodic RBF network is analyzed. It is then shown that the frequency response is asymptotically equivalent to the ideal sine interpolation, and that the periodic RBF network is closer to the ideal sine interpolation than the cubic spline and Lanczos interpolations","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":"130413780","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.2005.1689106
Yanyun Qu, Cuihua Li, N. Zheng
Airport is one of the key transportation targets. Airport detection is very important in military and civil fields. A novel method to detect airports from a single image is proposed in this paper. It combines texture features with shape features, and uses support vector machine as a classification function. Canny edge detector is firstly used, then short lines and curves are removed, and long straight lines are detected by Hough transform, at last the airport runways are discriminated by support vector machine. The experimental results demonstrate the efficacy of the proposed automatic airport-detection method
{"title":"Airport Detection Base on Support Vector Machine from A Single Image","authors":"Yanyun Qu, Cuihua Li, N. Zheng","doi":"10.1109/ICICS.2005.1689106","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689106","url":null,"abstract":"Airport is one of the key transportation targets. Airport detection is very important in military and civil fields. A novel method to detect airports from a single image is proposed in this paper. It combines texture features with shape features, and uses support vector machine as a classification function. Canny edge detector is firstly used, then short lines and curves are removed, and long straight lines are detected by Hough transform, at last the airport runways are discriminated by support vector machine. The experimental results demonstrate the efficacy of the proposed automatic airport-detection method","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":"126861034","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}
In MIMO channel, the presence of scatters results in angular spread. The point source model corresponding to discrete direction of arrival (DOA) becomes restrictive and leads to DOA estimation errors. To compensate for this effect, the distributed source model is proposed. A first order Taylor series expansion of the steering vector is derived, which is similar to the point source model. The proposed method is a possible alternative to MUSIC for the central DOA estimation. The algorithm that has lower computational cost can be used for sources with different distribution functions in MIMO channel. Simulations clearly demonstrate that the proposed method is not only effective, but also enjoys better SNR performance compared with MUSIC
{"title":"Direction of Arrival Estimation Based on Distributed Sources Model in MIMO Channel Environment","authors":"Yinghua Han, Jinkuan Wang, Xin Song, Zhigang Liu, Yanbo Xue","doi":"10.1109/ICICS.2005.1689253","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689253","url":null,"abstract":"In MIMO channel, the presence of scatters results in angular spread. The point source model corresponding to discrete direction of arrival (DOA) becomes restrictive and leads to DOA estimation errors. To compensate for this effect, the distributed source model is proposed. A first order Taylor series expansion of the steering vector is derived, which is similar to the point source model. The proposed method is a possible alternative to MUSIC for the central DOA estimation. The algorithm that has lower computational cost can be used for sources with different distribution functions in MIMO channel. Simulations clearly demonstrate that the proposed method is not only effective, but also enjoys better SNR performance compared with MUSIC","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"30 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":"126986617","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.2005.1689171
Xiangwei Kong, Zi-Ren Wang, Xingang You
Steganography is the art of communicating a message by embedding it into multimedia data without drawing any suspicions. Optimal parity assignment (OPA) algorithm is one of palette image steganographic methods. But there is still no effective steganalytic method that can attack it reliably. In this paper, we present a statistical steganalysis for detecting the secret messages embedded by using OPA algorithm. Based on the analysis of RTS (replacement-transfer structure) of index replacement in GIF-based steganography, we explore the singular statistic of core elements in OPA stego-images via convergent continuous replacement (CCR) operation. On the other hand, we can estimate the statistic of cover image from stego-image by a special filtering operation. With the estimation of cover image statistic and the singular statistic of the stego-image, the length of secret messages embedded in GIF images with OPA algorithm can be estimated. The experimental results indicate that our algorithm can estimate the length of hidden messages accurately
{"title":"Steganalysis of Palette Images: Attack Optimal Parity Assignment Algorithm","authors":"Xiangwei Kong, Zi-Ren Wang, Xingang You","doi":"10.1109/ICICS.2005.1689171","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689171","url":null,"abstract":"Steganography is the art of communicating a message by embedding it into multimedia data without drawing any suspicions. Optimal parity assignment (OPA) algorithm is one of palette image steganographic methods. But there is still no effective steganalytic method that can attack it reliably. In this paper, we present a statistical steganalysis for detecting the secret messages embedded by using OPA algorithm. Based on the analysis of RTS (replacement-transfer structure) of index replacement in GIF-based steganography, we explore the singular statistic of core elements in OPA stego-images via convergent continuous replacement (CCR) operation. On the other hand, we can estimate the statistic of cover image from stego-image by a special filtering operation. With the estimation of cover image statistic and the singular statistic of the stego-image, the length of secret messages embedded in GIF images with OPA algorithm can be estimated. The experimental results indicate that our algorithm can estimate the length of hidden messages accurately","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"20 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":"123969744","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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