Pub Date : 2008-12-08DOI: 10.1109/PIMRC.2008.4699767
C. Murthy
This paper considers the design and analysis of a filter at the receiver of a source coding system to mitigate the excess Mean-Squared Error (MSE) distortion caused due to channel errors. It is assumed that the source encoder is channel-agnostic, i.e., that a vector quantization (VQ) based compression designed for a noiseless channel is employed. The index output by the source encoder is sent over a noisy memoryless discrete symmetric channel, and the possibly incorrect received index is decoded by the corresponding VQ decoder. The output of the VQ decoder is processed by a receive filter to obtain an estimate of the source instantiation. In the sequel, the optimum linear receive filter structure to minimize the overall MSE is derived, and shown to have a minimum-mean squared error receiver type structure. Further, expressions are derived for the resulting high-rate MSE performance. The performance is compared with the MSE obtained using conventional VQ as well as the channel optimized VQ. The accuracy of the expressions is demonstrated through Monte Carlo simulations.
{"title":"Receiver-only optimized Vector Quantization for noisy channels","authors":"C. Murthy","doi":"10.1109/PIMRC.2008.4699767","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699767","url":null,"abstract":"This paper considers the design and analysis of a filter at the receiver of a source coding system to mitigate the excess Mean-Squared Error (MSE) distortion caused due to channel errors. It is assumed that the source encoder is channel-agnostic, i.e., that a vector quantization (VQ) based compression designed for a noiseless channel is employed. The index output by the source encoder is sent over a noisy memoryless discrete symmetric channel, and the possibly incorrect received index is decoded by the corresponding VQ decoder. The output of the VQ decoder is processed by a receive filter to obtain an estimate of the source instantiation. In the sequel, the optimum linear receive filter structure to minimize the overall MSE is derived, and shown to have a minimum-mean squared error receiver type structure. Further, expressions are derived for the resulting high-rate MSE performance. The performance is compared with the MSE obtained using conventional VQ as well as the channel optimized VQ. The accuracy of the expressions is demonstrated through Monte Carlo simulations.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123347882","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699450
Sung-Joon Park, Moo-Kwang Byeon
The recently suggested triangular quadrature amplitude modulation (TQAM) provides considerable power gain over square quadrature amplitude modulation (SQAM) at the expense of slight increase in detection complexity. However, power gain of the TQAM is limited on account of the constraint that signal points are regularly distributed at the vertexes of contiguous equilateral triangles. In this paper, we investigate a modified signal constellation of the TQAM where signal points are irregularly distributed while preserving triangular structure, and calculate achievable power gain of the proposed scheme. We also address optimum and suboptimum bit stream mapping methods and suggest a simple and optimum detection method for the constellation to be meaningful in practical implementation. Analysis and simulation show that the proposed constellation provides power gains of 0.62 dB and 0.20 dB over the SQAM and the TQAM at a target symbol error rate of 10-6 for 64-ary case.
{"title":"Irregularly distributed triangular quadrature amplitude modulation","authors":"Sung-Joon Park, Moo-Kwang Byeon","doi":"10.1109/PIMRC.2008.4699450","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699450","url":null,"abstract":"The recently suggested triangular quadrature amplitude modulation (TQAM) provides considerable power gain over square quadrature amplitude modulation (SQAM) at the expense of slight increase in detection complexity. However, power gain of the TQAM is limited on account of the constraint that signal points are regularly distributed at the vertexes of contiguous equilateral triangles. In this paper, we investigate a modified signal constellation of the TQAM where signal points are irregularly distributed while preserving triangular structure, and calculate achievable power gain of the proposed scheme. We also address optimum and suboptimum bit stream mapping methods and suggest a simple and optimum detection method for the constellation to be meaningful in practical implementation. Analysis and simulation show that the proposed constellation provides power gains of 0.62 dB and 0.20 dB over the SQAM and the TQAM at a target symbol error rate of 10-6 for 64-ary case.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120946919","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699544
H. Miyajima, L. Zhang, H. Hayashi, T. Fujii
In recent years, adding mobility technology to heterogeneous access networks has become important due to the growth and diversification of broadband access networks. For the simple and easily realization of seamless mobility in heterogeneous access networks, our previous paper proposed the All-SIP mobility architecture; it uses only SIP components in order to maintain both TCP and UDP communication sessions in heterogeneous access networks, but it was limited to only a few major TCP applications. This paper presents the enhanced All-SIP (eAll-SIP) mobility architecture which utilizes UDP encapsulation to suit all TCP applications; evaluation results of a prototype system including application programs are presented.
{"title":"An implementation of enhanced all-SIP mobility","authors":"H. Miyajima, L. Zhang, H. Hayashi, T. Fujii","doi":"10.1109/PIMRC.2008.4699544","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699544","url":null,"abstract":"In recent years, adding mobility technology to heterogeneous access networks has become important due to the growth and diversification of broadband access networks. For the simple and easily realization of seamless mobility in heterogeneous access networks, our previous paper proposed the All-SIP mobility architecture; it uses only SIP components in order to maintain both TCP and UDP communication sessions in heterogeneous access networks, but it was limited to only a few major TCP applications. This paper presents the enhanced All-SIP (eAll-SIP) mobility architecture which utilizes UDP encapsulation to suit all TCP applications; evaluation results of a prototype system including application programs are presented.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121510609","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699628
R. Hoshyar, R. Tafazolli
A generic cooperative MIMO BICM system is described. Achievable rates are computed based on the extended equivalent binary input channel model of the original BICM system. Full decode and forward is assumed at the relay node. Two types of two-phased transmission/reception protocols are employed to establish orthogonal transmission/reception of the relay node. The achievable rate results are provided for different combinations of modulation orders and the number of antennas used at the source and relay nodes. Quantitative results provided in this paper could serve as a guide on when to engage cooperative transmission and how to choose proper constellations and puncturing ratios for the practical BICM coded systems. Comparison of the considered BICM system with other possible cooperative coded systems is also crucial that this paper due to lack of space for exposition misses to address.
{"title":"Achievable full decode and forward rates for Cooperative MIMO BICM systems","authors":"R. Hoshyar, R. Tafazolli","doi":"10.1109/PIMRC.2008.4699628","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699628","url":null,"abstract":"A generic cooperative MIMO BICM system is described. Achievable rates are computed based on the extended equivalent binary input channel model of the original BICM system. Full decode and forward is assumed at the relay node. Two types of two-phased transmission/reception protocols are employed to establish orthogonal transmission/reception of the relay node. The achievable rate results are provided for different combinations of modulation orders and the number of antennas used at the source and relay nodes. Quantitative results provided in this paper could serve as a guide on when to engage cooperative transmission and how to choose proper constellations and puncturing ratios for the practical BICM coded systems. Comparison of the considered BICM system with other possible cooperative coded systems is also crucial that this paper due to lack of space for exposition misses to address.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121530159","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699575
N. Ewald, A. Kemp
This paper presents a performance evaluation of a hybrid FEC/SR-ARQ (HARQ) analytical model. This model maps the impact of finite link layer (LL) buffer size, retransmissions and code rate on HARQ performance. The analytical model is validated by extensive ns-2 simulations. An accurate HARQ model will allow better prediction of performance through not only wireless link efficiency but also higher layer (particularly transport layer) protocols. This can be translated to improved utilisation of network resources and therefore greater end-user and network provider satisfaction.
{"title":"Performance analysis of link-layer hybrid ARQ with finite buffer size","authors":"N. Ewald, A. Kemp","doi":"10.1109/PIMRC.2008.4699575","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699575","url":null,"abstract":"This paper presents a performance evaluation of a hybrid FEC/SR-ARQ (HARQ) analytical model. This model maps the impact of finite link layer (LL) buffer size, retransmissions and code rate on HARQ performance. The analytical model is validated by extensive ns-2 simulations. An accurate HARQ model will allow better prediction of performance through not only wireless link efficiency but also higher layer (particularly transport layer) protocols. This can be translated to improved utilisation of network resources and therefore greater end-user and network provider satisfaction.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114714683","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699857
W. Wong, H. Aghvami, S. Wolak
The main goal of this article is to show a context-aware PAA multi-agent system (CAPMAS) framework and how it conveys context-aware computing and agent technologies into ubiquitous system. We use context-awareness to provide computing environments with the ability to usefully adapt the services or information they provide. The dasiaagent technologiespsila take into account of different service solutions, which form the ultimate link to the context aware computing. In this article, we shall explore some of the basic agent technologies that lead us to develop our context awareness personal assistant agent (PAA) based systems and concepts.
{"title":"Context-Aware Personal Assistant Agent Multi-Agent System","authors":"W. Wong, H. Aghvami, S. Wolak","doi":"10.1109/PIMRC.2008.4699857","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699857","url":null,"abstract":"The main goal of this article is to show a context-aware PAA multi-agent system (CAPMAS) framework and how it conveys context-aware computing and agent technologies into ubiquitous system. We use context-awareness to provide computing environments with the ability to usefully adapt the services or information they provide. The dasiaagent technologiespsila take into account of different service solutions, which form the ultimate link to the context aware computing. In this article, we shall explore some of the basic agent technologies that lead us to develop our context awareness personal assistant agent (PAA) based systems and concepts.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114728650","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699755
Ingmar Blau, G. Wunder, I. Karla, R. Sigle
In this paper we cover the problem of resource allocation in terms of optimum air-interface and cell selection in cellular, heterogeneous multi-air-interface scenarios. For a given set of voice users with minimum quality of service requirements and a set of best effort users we find the optimum allocation that guarantees service for the voice users and maximizes the sum utility of the best effort users. Our model applies for arbitrary heterogeneous scenarios where the air-interfaces belong to the class of interference limited systems like UMTS or to a class with orthogonal resource assignment such as TDMA based GSM or WLAN. We achieve convexity of the problem by a transformation into the domain of mean square errors. Using a dual problem formulation we derive straight forward assignment rules and develop a decentralized algorithm, which solves the optimization problem. Simulation results for a heterogeneous UMTS/GSM scenario show high performance gains of the proposed algorithm compared to a Load Balancing strategy.
{"title":"Decentralized utility maximization in heterogeneous multi-cell scenarios","authors":"Ingmar Blau, G. Wunder, I. Karla, R. Sigle","doi":"10.1109/PIMRC.2008.4699755","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699755","url":null,"abstract":"In this paper we cover the problem of resource allocation in terms of optimum air-interface and cell selection in cellular, heterogeneous multi-air-interface scenarios. For a given set of voice users with minimum quality of service requirements and a set of best effort users we find the optimum allocation that guarantees service for the voice users and maximizes the sum utility of the best effort users. Our model applies for arbitrary heterogeneous scenarios where the air-interfaces belong to the class of interference limited systems like UMTS or to a class with orthogonal resource assignment such as TDMA based GSM or WLAN. We achieve convexity of the problem by a transformation into the domain of mean square errors. Using a dual problem formulation we derive straight forward assignment rules and develop a decentralized algorithm, which solves the optimization problem. Simulation results for a heterogeneous UMTS/GSM scenario show high performance gains of the proposed algorithm compared to a Load Balancing strategy.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114846649","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699922
Emil Björnson, B. Ottersten
This paper considers quantization and exact minimum mean square error (MMSE) estimation of the squared Frobenius norm and the squared spectral norm of a Rayleigh fading multiple-input multiple-output (MIMO) channel with one-sided spatial correlation. The Frobenius and spectral norms are of great importance when describing the achievable capacity of many wireless communication systems; in particularly, they correspond to the signal-to-noise ratio (SNR) of space-time block coded and maximum ratio combining transmissions, respectively. Herein, a general quantization framework is presented, where the quantization levels are determined to maximize the feedback entropy. Quantization based on the post-user-selection distribution is discussed, and analyzed for a specific scheduler. Finally, exact results on MMSE estimation of the capacity and the SNR, conditioned on a quantized channel norm, are presented.
{"title":"Post-user-selection quantization and estimation of correlated Frobenius and spectral channel norms","authors":"Emil Björnson, B. Ottersten","doi":"10.1109/PIMRC.2008.4699922","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699922","url":null,"abstract":"This paper considers quantization and exact minimum mean square error (MMSE) estimation of the squared Frobenius norm and the squared spectral norm of a Rayleigh fading multiple-input multiple-output (MIMO) channel with one-sided spatial correlation. The Frobenius and spectral norms are of great importance when describing the achievable capacity of many wireless communication systems; in particularly, they correspond to the signal-to-noise ratio (SNR) of space-time block coded and maximum ratio combining transmissions, respectively. Herein, a general quantization framework is presented, where the quantization levels are determined to maximize the feedback entropy. Quantization based on the post-user-selection distribution is discussed, and analyzed for a specific scheduler. Finally, exact results on MMSE estimation of the capacity and the SNR, conditioned on a quantized channel norm, are presented.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"90 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124321547","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699841
K. Voulgaris, I. Ashraf, T. Karveli, H. Aghvami
Battery-powered wireless sensor networks (WSNs) are highly constrained in energy. In order to maximize the node and network lifetime, the energy usage has to be optimized. In this paper, we analyze the sources of energy consumption in p-persistent CSMA for non-saturated conditions, showing that maximum efficiency is achieved for a narrow range of traffic load. Furthermore, the optimum traffic load is a function of the consumption characteristics of the node and it does not guarantee maximum system throughput. Our analytical framework can be applied in various CSMA variants, thus aiding in the design of Medium Access Control (MAC) protocols for WSNs.
{"title":"Energy efficiency of p-persistent CSMA under variable traffic conditions","authors":"K. Voulgaris, I. Ashraf, T. Karveli, H. Aghvami","doi":"10.1109/PIMRC.2008.4699841","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699841","url":null,"abstract":"Battery-powered wireless sensor networks (WSNs) are highly constrained in energy. In order to maximize the node and network lifetime, the energy usage has to be optimized. In this paper, we analyze the sources of energy consumption in p-persistent CSMA for non-saturated conditions, showing that maximum efficiency is achieved for a narrow range of traffic load. Furthermore, the optimum traffic load is a function of the consumption characteristics of the node and it does not guarantee maximum system throughput. Our analytical framework can be applied in various CSMA variants, thus aiding in the design of Medium Access Control (MAC) protocols for WSNs.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"1957 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128032096","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 : 2008-12-08DOI: 10.1109/PIMRC.2008.4699897
C. Bettstetter, Günther Brandner, R. Vilzmann
Considering n nodes performing random access using ALOHA with s slots, we study the probability that there occurs a non-colliding message in the first non-empty slot. If each node transmits with probability p in each slot and the number of slots is sufficiently large, a non-colliding first message occurs with probability Phi = 1-np/2 for large n and small np. If the number of slots is limited, the probability Phi is lower but can be maximized choosing an optimal p. To maximize Phi further, nodes can apply a slot-dependent transmit probability pi with i = 1, ..., s. It is shown that a ldquoslow start strategy,rdquo in which pi is low for low i and increases with increasing i, is beneficial. Our main contribution is an equation for the pi values that maximize Phi. We analyze how a higher probability of a non-colliding first message comes at the price of an increased delay of such a message. Besides being of interest for the theory of random access, the results are practically applicable to node selection protocols, such as relay selection in cooperative wireless networks.
{"title":"On colliding first messages in slotted ALOHA","authors":"C. Bettstetter, Günther Brandner, R. Vilzmann","doi":"10.1109/PIMRC.2008.4699897","DOIUrl":"https://doi.org/10.1109/PIMRC.2008.4699897","url":null,"abstract":"Considering n nodes performing random access using ALOHA with s slots, we study the probability that there occurs a non-colliding message in the first non-empty slot. If each node transmits with probability p in each slot and the number of slots is sufficiently large, a non-colliding first message occurs with probability Phi = 1-np/2 for large n and small np. If the number of slots is limited, the probability Phi is lower but can be maximized choosing an optimal p. To maximize Phi further, nodes can apply a slot-dependent transmit probability pi with i = 1, ..., s. It is shown that a ldquoslow start strategy,rdquo in which pi is low for low i and increases with increasing i, is beneficial. Our main contribution is an equation for the pi values that maximize Phi. We analyze how a higher probability of a non-colliding first message comes at the price of an increased delay of such a message. Besides being of interest for the theory of random access, the results are practically applicable to node selection protocols, such as relay selection in cooperative wireless networks.","PeriodicalId":125554,"journal":{"name":"2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128048267","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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