Pub Date : 2013-06-12DOI: 10.1109/ICCA.2013.6565050
Xinli Wang, Jiangang Lu, Qinmin Yang, W. Cai, Youxian Sun
In this paper, an empirical model based on least square support vector machine (LSSVM) method to predict the output air conditions in a packed tower liquid desiccant dehumidifier is developed. By analysis of the coupled heat and mass transfer between the process air and desiccant solution, six variables are used as the inputs of the LSSVM model, namely: desiccant solution and air flow rates, desiccant solution and air inlet temperature, desiccant concentration, and air relative humidity. Meanwhile, outlet air temperature and relative humidity related with the performance of the dehumidifier are considered as the outputs of the LSSVM model. Compared with the existing theoretical models, the present one is very simple, yet accuracy, and does not need complex theoretical analysis. The experimental results illustrate the effectiveness of the proposed model on performance predicting in a packed tower liquid desiccant dehumidifier. This developed model is expected to have widely applications in performance evaluation, operational monitoring, fault detection and diagnosis.
{"title":"Performance evaluation of packed tower liquid desiccant dehumidifier based on LSSVM","authors":"Xinli Wang, Jiangang Lu, Qinmin Yang, W. Cai, Youxian Sun","doi":"10.1109/ICCA.2013.6565050","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6565050","url":null,"abstract":"In this paper, an empirical model based on least square support vector machine (LSSVM) method to predict the output air conditions in a packed tower liquid desiccant dehumidifier is developed. By analysis of the coupled heat and mass transfer between the process air and desiccant solution, six variables are used as the inputs of the LSSVM model, namely: desiccant solution and air flow rates, desiccant solution and air inlet temperature, desiccant concentration, and air relative humidity. Meanwhile, outlet air temperature and relative humidity related with the performance of the dehumidifier are considered as the outputs of the LSSVM model. Compared with the existing theoretical models, the present one is very simple, yet accuracy, and does not need complex theoretical analysis. The experimental results illustrate the effectiveness of the proposed model on performance predicting in a packed tower liquid desiccant dehumidifier. This developed model is expected to have widely applications in performance evaluation, operational monitoring, fault detection and diagnosis.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124097533","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6564861
Xiang Gong, Yaodong Pan, Jianning Li, H. Su
This paper is to develop a novel consensus algorithm or protocol for multi-agent systems in the event of communication link failure over the network. System dynamics are defined as a double-integrator system with the topology of MAS modeled by the graph theory. Bernoulli distribution is applied to represent the data dropout during operation. The sufficient conditions for the stabilization controller design is developed by Lyapunov-based methodologies and Linear matrix inequality (LMIs) techniques. The feasibility of the given LMIs is analyzed to ensure the stabilization controller design, which ensures the MAS to achieve the consensus. Leader-following numerical simulations with a group of agents are successfully conducted to demonstrate the effectiveness of the novel consensus algorithm in this paper. The results are studied to show that the consensus achievement is incorporating with the data loss probability up to 95%, however the higher data loss rate may cause longer time for agents to achieve consensus.
{"title":"Leader following consensus for multi-agent systems with stochastic packet dropout","authors":"Xiang Gong, Yaodong Pan, Jianning Li, H. Su","doi":"10.1109/ICCA.2013.6564861","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6564861","url":null,"abstract":"This paper is to develop a novel consensus algorithm or protocol for multi-agent systems in the event of communication link failure over the network. System dynamics are defined as a double-integrator system with the topology of MAS modeled by the graph theory. Bernoulli distribution is applied to represent the data dropout during operation. The sufficient conditions for the stabilization controller design is developed by Lyapunov-based methodologies and Linear matrix inequality (LMIs) techniques. The feasibility of the given LMIs is analyzed to ensure the stabilization controller design, which ensures the MAS to achieve the consensus. Leader-following numerical simulations with a group of agents are successfully conducted to demonstrate the effectiveness of the novel consensus algorithm in this paper. The results are studied to show that the consensus achievement is incorporating with the data loss probability up to 95%, however the higher data loss rate may cause longer time for agents to achieve consensus.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127586984","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6565171
K. Yogaprakash, Wee-Seng Soh
Over the last several years, there has been rapid growth in the adoption of Wireless Local Area Networks (WLAN) technology. While WLAN technology is primarily used for internet/intranet communication, the existing hardware infrastructure of WLAN can also be used to support localization systems. This paper discusses the development of a low-cost localisation system for use in Singapore's hospitals, most of which are covered by a nation-wide wireless broadband programme. Such a system can be used to track children or critical equipment in the hospitals. This system involves the use of received signal strength indicator values (RSSI) of unique beacons to derive the position of a low-cost mobile node that is capable of scanning for these beacons' RSSI values. This paper discusses the implementation details of the system and the accuracy of 2 indoor positioning algorithms from tests conducted in a lab area of 165m2.
{"title":"Indoor location tracking using low-cost modules","authors":"K. Yogaprakash, Wee-Seng Soh","doi":"10.1109/ICCA.2013.6565171","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6565171","url":null,"abstract":"Over the last several years, there has been rapid growth in the adoption of Wireless Local Area Networks (WLAN) technology. While WLAN technology is primarily used for internet/intranet communication, the existing hardware infrastructure of WLAN can also be used to support localization systems. This paper discusses the development of a low-cost localisation system for use in Singapore's hospitals, most of which are covered by a nation-wide wireless broadband programme. Such a system can be used to track children or critical equipment in the hospitals. This system involves the use of received signal strength indicator values (RSSI) of unique beacons to derive the position of a low-cost mobile node that is capable of scanning for these beacons' RSSI values. This paper discusses the implementation details of the system and the accuracy of 2 indoor positioning algorithms from tests conducted in a lab area of 165m2.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122220018","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6565008
Yue Li, Shouguang Wang, J. Yang
Petri nets can be viewed as graphical models and mathematical tools to study discrete event system. As a basic analysis tool of Petri nets, reachability trees are fundamental for systematically investigating many characteristics. In this paper, a new reachability tree for unbounded generalized Petri nets is proposed. This new method can decrease the number of nodes in the new reachability tree besides avoidance of some spurious markings which appear in other reachability trees. Several examples are provided to illustrate its superiority.
{"title":"A new reachability tree for unbounded Petri nets","authors":"Yue Li, Shouguang Wang, J. Yang","doi":"10.1109/ICCA.2013.6565008","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6565008","url":null,"abstract":"Petri nets can be viewed as graphical models and mathematical tools to study discrete event system. As a basic analysis tool of Petri nets, reachability trees are fundamental for systematically investigating many characteristics. In this paper, a new reachability tree for unbounded generalized Petri nets is proposed. This new method can decrease the number of nodes in the new reachability tree besides avoidance of some spurious markings which appear in other reachability trees. Several examples are provided to illustrate its superiority.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116794390","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6564893
D. Sui, Roar Nybø, V. Azizi
The increase of drilling safety and the reduction of drilling operation costs, especially the improvement of drilling efficiency, are two important considerations. In general the rate of penetration (ROP) optimization means that the drilling parameters such as weight on bit (WOB) and rotary speed (RPM) are adjusted to drill the present formation most efficiently. In this paper, the Bourgoyne and Young ROP model had been selected to study the effects of several parameters during drilling operation. We present an advanced method for the ROP calculation and its optimization. A moving-horizon multiple regression method is proposed, which reduces the estimation error of the existing ROP models by continuously calibrating the model coefficients based on real-time data. Furthermore, a model predictive control (MPC) strategy is applied to achieve the ROP optimization to satisfy drilling requirements. The performance of the methodology is demonstrated by using realworld data from a North Sea well.
{"title":"Real-time optimization of rate of penetration during drilling operation","authors":"D. Sui, Roar Nybø, V. Azizi","doi":"10.1109/ICCA.2013.6564893","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6564893","url":null,"abstract":"The increase of drilling safety and the reduction of drilling operation costs, especially the improvement of drilling efficiency, are two important considerations. In general the rate of penetration (ROP) optimization means that the drilling parameters such as weight on bit (WOB) and rotary speed (RPM) are adjusted to drill the present formation most efficiently. In this paper, the Bourgoyne and Young ROP model had been selected to study the effects of several parameters during drilling operation. We present an advanced method for the ROP calculation and its optimization. A moving-horizon multiple regression method is proposed, which reduces the estimation error of the existing ROP models by continuously calibrating the model coefficients based on real-time data. Furthermore, a model predictive control (MPC) strategy is applied to achieve the ROP optimization to satisfy drilling requirements. The performance of the methodology is demonstrated by using realworld data from a North Sea well.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117226805","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6565073
Feng Zhou, Lu Liu, G. Feng
This paper is concerned with the stochastic stability of a class of discrete-time networked control systems (NCS) with uncertain network-induced time delays and missing measurements by using a fuzzy decentralized control approach. We model nonlinear systems in Takagi-Sugetno (T-S) form and then develop fuzzy decentralized state feedback controllers with missing measurements. A sufficient condition on stochastic stability in the mean-square sense for the NCS is obtained by using Lyapunov function method. The constructive design of the controllers is expressed as the linear matrix inequality (LMI). Finally, a numerical simulation is provided to illustrate the result of this paper.
{"title":"Fuzzy decentralized control for a class of networked control systems with time delays and missing measurements","authors":"Feng Zhou, Lu Liu, G. Feng","doi":"10.1109/ICCA.2013.6565073","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6565073","url":null,"abstract":"This paper is concerned with the stochastic stability of a class of discrete-time networked control systems (NCS) with uncertain network-induced time delays and missing measurements by using a fuzzy decentralized control approach. We model nonlinear systems in Takagi-Sugetno (T-S) form and then develop fuzzy decentralized state feedback controllers with missing measurements. A sufficient condition on stochastic stability in the mean-square sense for the NCS is obtained by using Lyapunov function method. The constructive design of the controllers is expressed as the linear matrix inequality (LMI). Finally, a numerical simulation is provided to illustrate the result of this paper.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"375 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131075676","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6565128
Jianjun Gao, Y. Xiong
The conditional value-at-risk(CVaR) is defined as the expected value of the tail distribution exceeding Value-at-Risk(VaR). As a kind of risk measure, CVaR recently receives much attention from both academic field and financial industry. However, due to the tractability, most of the studies on mean-CVaR portfolio optimization are restricted to the static portfolio analysis, where only buy-and-hold portfolio policy is computed numerically. In this paper, we study the dynamic portfolio policy of the mean-CVaR portfolio model, in which the investor is allowed to adjust the investment policy dynamically to minimize the CVaR of the portfolio as well as keep certain level of the expected return. On recognizing the ill-posed nature of such a problem in continuous-time model, we modify the model by imposing the limited funding level as the upper bound of the wealth. By using the martingale approach, we develop the explicit portfolio policy and mean-CVaR efficient frontier for such a problem.
{"title":"Dynamic mean-CVaR portfolio optimization in continuous-time","authors":"Jianjun Gao, Y. Xiong","doi":"10.1109/ICCA.2013.6565128","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6565128","url":null,"abstract":"The conditional value-at-risk(CVaR) is defined as the expected value of the tail distribution exceeding Value-at-Risk(VaR). As a kind of risk measure, CVaR recently receives much attention from both academic field and financial industry. However, due to the tractability, most of the studies on mean-CVaR portfolio optimization are restricted to the static portfolio analysis, where only buy-and-hold portfolio policy is computed numerically. In this paper, we study the dynamic portfolio policy of the mean-CVaR portfolio model, in which the investor is allowed to adjust the investment policy dynamically to minimize the CVaR of the portfolio as well as keep certain level of the expected return. On recognizing the ill-posed nature of such a problem in continuous-time model, we modify the model by imposing the limited funding level as the upper bound of the wealth. By using the martingale approach, we develop the explicit portfolio policy and mean-CVaR efficient frontier for such a problem.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131082549","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6564869
Jun Cheng, Yong Zeng, Hong Zhu, S. Zhong, Yuping Zhang
This paper is concerned with the H∞ filter design problem for a class of switched discrete-time system with average dwell time under asynchronous switching. Since the unmatched filters are allowed to perform in the interval of asynchronous switching before the matched ones, the issue of asynchronous switching between system modes and filters are investigated based on the average dwell time approach and multiple Lyapunov-like function method, and the sufficient conditions are presented for the filtering error system to be exponentially stable with a prescribed H∞ performance. At last, an example is given to illustrate the effectiveness of the proposed method.
{"title":"H∞ filtering of discrete-time switched systems with average dwell time under asynchronous switching","authors":"Jun Cheng, Yong Zeng, Hong Zhu, S. Zhong, Yuping Zhang","doi":"10.1109/ICCA.2013.6564869","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6564869","url":null,"abstract":"This paper is concerned with the H∞ filter design problem for a class of switched discrete-time system with average dwell time under asynchronous switching. Since the unmatched filters are allowed to perform in the interval of asynchronous switching before the matched ones, the issue of asynchronous switching between system modes and filters are investigated based on the average dwell time approach and multiple Lyapunov-like function method, and the sufficient conditions are presented for the filtering error system to be exponentially stable with a prescribed H∞ performance. At last, an example is given to illustrate the effectiveness of the proposed method.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131557963","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6565019
Yong-ming Li, K. Gu, Shengyuan Xu
The discretized Lyapunov-Krasovskii functional (DLF) method is asymptotically accurate in stability analysis for time-delay systems. In general, a system may have multiple stable delay intervals, and DLF is especially effective to study such systems. In this article, a DLF-based method is proposed to accurately estimate the maximum stable delay interval without using bisection, when one point in this interval is given. The formulation uses generalized eigenvalue problem (GEVP) of linear matrix inequalities (LMIs), and iterations may be used to reach the analytical limits either in finite number of steps or asymptotically. The coupled differential-difference equations are used to illustrate the method. However, the idea can be easily adapted to traditional differential-difference equation setting.
{"title":"Estimating stable delay interval using discretized Lyapunov-Krasovskii functional method","authors":"Yong-ming Li, K. Gu, Shengyuan Xu","doi":"10.1109/ICCA.2013.6565019","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6565019","url":null,"abstract":"The discretized Lyapunov-Krasovskii functional (DLF) method is asymptotically accurate in stability analysis for time-delay systems. In general, a system may have multiple stable delay intervals, and DLF is especially effective to study such systems. In this article, a DLF-based method is proposed to accurately estimate the maximum stable delay interval without using bisection, when one point in this interval is given. The formulation uses generalized eigenvalue problem (GEVP) of linear matrix inequalities (LMIs), and iterations may be used to reach the analytical limits either in finite number of steps or asymptotically. The coupled differential-difference equations are used to illustrate the method. However, the idea can be easily adapted to traditional differential-difference equation setting.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132358167","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 : 2013-06-12DOI: 10.1109/ICCA.2013.6564995
Feng Xiaoliang, Wen Chenglin, Xu Lizhong
Multi-sensor fusion for OOSM system is still an open question in the field of wireless sensor network. In this paper, a new distributed sequential fusion algorithm for multi-sensor system with one-step-lag OOSMs is proposed in the sense of minimum trace of error covariance matrix. The main idea of this real time sequential fusion algorithm is that: firstly, an equivalent measurement “sampled” at the fusion time is obtained, once a measurement comes to the fusion center; then, a local estimation of the current state is obtained based on the equivalent measurement; furthermore, first round fusion is carried out for the second local estimate and the first local estimate to obtain the first local fusion when the second measurement comes; another round of fusion process is carried out for the third local estimate and the first local fusion estimation. Repeating this process until all the measurements are fused, sequentially. The final simulation illustrates its efficiency and validity of the proposed method.
{"title":"Multi-sensor multi-OOSM distributed sequential fusion filtering","authors":"Feng Xiaoliang, Wen Chenglin, Xu Lizhong","doi":"10.1109/ICCA.2013.6564995","DOIUrl":"https://doi.org/10.1109/ICCA.2013.6564995","url":null,"abstract":"Multi-sensor fusion for OOSM system is still an open question in the field of wireless sensor network. In this paper, a new distributed sequential fusion algorithm for multi-sensor system with one-step-lag OOSMs is proposed in the sense of minimum trace of error covariance matrix. The main idea of this real time sequential fusion algorithm is that: firstly, an equivalent measurement “sampled” at the fusion time is obtained, once a measurement comes to the fusion center; then, a local estimation of the current state is obtained based on the equivalent measurement; furthermore, first round fusion is carried out for the second local estimate and the first local estimate to obtain the first local fusion when the second measurement comes; another round of fusion process is carried out for the third local estimate and the first local fusion estimation. Repeating this process until all the measurements are fused, sequentially. The final simulation illustrates its efficiency and validity of the proposed method.","PeriodicalId":336534,"journal":{"name":"2013 10th IEEE International Conference on Control and Automation (ICCA)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128171948","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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