Pub Date : 2009-11-01DOI: 10.1109/ICSCS.2009.5412220
K. Triantafyllopoulos, F. Aldebrez, A. S. I. Zinober, M. Tokhi
This paper presents an investigation into the development of a dynamic modelling and feedback control scheme for rigid body motion control of a twin rotor multi-input multi-output system (TRMS) in hovering mode. The proposed approach is based on a two stage methodology: (i) the dynamic parametric model is developed using the Bayesian paradigm; several validation tests are conducted for assessing the suitability of the model; (ii) development of a feedback control law comprising a three term PID compensator for rigid body motion control of the TRMS in the hovering mode. The developed control strategy is designed and implemented within the simulation environment of the TRMS rig using the Bayesian model. The performance of the proposed control scheme is assessed in terms of output tracking. This is accomplished by comparing the system response with the controller to one without control action (open loop configuration). The results have shown that improved closed loop tracking of the reference signal implies good damping and hence tighter control.
{"title":"Bayesian dynamic modelling and tracking control for flexible manoeuvring systems","authors":"K. Triantafyllopoulos, F. Aldebrez, A. S. I. Zinober, M. Tokhi","doi":"10.1109/ICSCS.2009.5412220","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412220","url":null,"abstract":"This paper presents an investigation into the development of a dynamic modelling and feedback control scheme for rigid body motion control of a twin rotor multi-input multi-output system (TRMS) in hovering mode. The proposed approach is based on a two stage methodology: (i) the dynamic parametric model is developed using the Bayesian paradigm; several validation tests are conducted for assessing the suitability of the model; (ii) development of a feedback control law comprising a three term PID compensator for rigid body motion control of the TRMS in the hovering mode. The developed control strategy is designed and implemented within the simulation environment of the TRMS rig using the Bayesian model. The performance of the proposed control scheme is assessed in terms of output tracking. This is accomplished by comparing the system response with the controller to one without control action (open loop configuration). The results have shown that improved closed loop tracking of the reference signal implies good damping and hence tighter control.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130067161","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412319
M. Rovini, Giuseppe Gentile, L. Fanucci
This paper describes the architecture of a flexible and reconfigurable processor for the computation of the state-metric recursion in a multi-standard BCJR decoder. The unit can serve binary as well as duo-binary codes with any number of states. The architecture is arranged into a cluster of state-metric processors plus two multiplexing networks for feedback and normalization, configured on-the-fly for the code in use. An optimized solution is presented allowing the support of every code among 8-state duo-binary, 8-state binary and 2-state binary codes, i.e., of every Turbo and LDPC code defined by the modern communication standards. The logical synthesis on different CMOS technologies shows that the architecture attains a maximum clock frequency of 450 MHz. Finally, the complexity overhead of such a flexible design is only about 18% w.r.t. optimized single-standard solutions.
{"title":"A flexible state-metric recursion unit for a multi-standard BCJR decoder","authors":"M. Rovini, Giuseppe Gentile, L. Fanucci","doi":"10.1109/ICSCS.2009.5412319","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412319","url":null,"abstract":"This paper describes the architecture of a flexible and reconfigurable processor for the computation of the state-metric recursion in a multi-standard BCJR decoder. The unit can serve binary as well as duo-binary codes with any number of states. The architecture is arranged into a cluster of state-metric processors plus two multiplexing networks for feedback and normalization, configured on-the-fly for the code in use. An optimized solution is presented allowing the support of every code among 8-state duo-binary, 8-state binary and 2-state binary codes, i.e., of every Turbo and LDPC code defined by the modern communication standards. The logical synthesis on different CMOS technologies shows that the architecture attains a maximum clock frequency of 450 MHz. Finally, the complexity overhead of such a flexible design is only about 18% w.r.t. optimized single-standard solutions.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132974264","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412684
I. Trigui, A. Laourine, S. Affes, A. Stephenne
The correlated bivariate G distribution with arbitrary and not necessarily identical parameters is addressed in this paper. This compound distribution, which is a mixture of arbitrary correlated Rayleigh and inverse Gaussian random variables (RVs), is very convenient for modeling correlated fading shadowing channels. New closed-form expressions for the probability density function (PDF), the cumulative density function (CDF) and the joint moments are provided to statistically characterize the bivariate G distribution. Furthermore, simpler expressions are obtained when considering independent inverse-Gaussian shadowing. Capitalizing on these theoretical expressions for the statistical characteristics of the correlated G distribution, the performance analysis of various diversity reception techniques, such as selection diversity (SD) and maximal ratio combining (MRC) over bivariate G fading channels is presented.
{"title":"Bivariate G distribution with arbitrary fading parameters","authors":"I. Trigui, A. Laourine, S. Affes, A. Stephenne","doi":"10.1109/ICSCS.2009.5412684","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412684","url":null,"abstract":"The correlated bivariate G distribution with arbitrary and not necessarily identical parameters is addressed in this paper. This compound distribution, which is a mixture of arbitrary correlated Rayleigh and inverse Gaussian random variables (RVs), is very convenient for modeling correlated fading shadowing channels. New closed-form expressions for the probability density function (PDF), the cumulative density function (CDF) and the joint moments are provided to statistically characterize the bivariate G distribution. Furthermore, simpler expressions are obtained when considering independent inverse-Gaussian shadowing. Capitalizing on these theoretical expressions for the statistical characteristics of the correlated G distribution, the performance analysis of various diversity reception techniques, such as selection diversity (SD) and maximal ratio combining (MRC) over bivariate G fading channels is presented.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130956242","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5414200
Meththa Samaranayake, Helen Ji, J. Ainscough
This paper presents a module placement tool developed by combining two well-known force directed algorithms. Even with the increase of usage of modules within designs, the industry holds a gap for module placement tools. Experimentation has shown that comparable results were achieved by the force-directed algorithms to that of current academic placement tools.
{"title":"Module placement based on hierarchical force directed approach","authors":"Meththa Samaranayake, Helen Ji, J. Ainscough","doi":"10.1109/ICSCS.2009.5414200","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5414200","url":null,"abstract":"This paper presents a module placement tool developed by combining two well-known force directed algorithms. Even with the increase of usage of modules within designs, the industry holds a gap for module placement tools. Experimentation has shown that comparable results were achieved by the force-directed algorithms to that of current academic placement tools.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129213678","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5414212
H. Osten, A. Laha, E. Bugiel, D. Schwendt, A. Fissel
Many materials systems are currently under consideration as potential replacements for SiO2 as the gate dielectric material for sub-0.1 µm CMOS technology. We present results for crystalline gadolinium oxides on silicon in the cubic bixbyite structure grown by solid source molecular beam epitaxy. On Si(100), crystalline Gd2O3 grows usually as (110)-oriented domains, with two orthogonal in-plane orientations. Layers grown under best vacuum conditions often exhibit poor dielectric properties due to the formation of crystalline interfacial silicide inclusions. Additional oxygen supply during growth improves the dielectric properties significantly. Layers grown by an optimized MBE process display a sufficiently high-K value to achieve equivalent oxide thickness values ≪ 1 nm, combined with ultra-low leakage current densities, good reliability, and high electrical breakdown voltage. A variety of MOS capacitors and field effect transistors has been fabricated based on these layers. Efficient manipulation of Si(100) 4° miscut substrate surfaces can lead to single domain epitaxial Gd2O3 layer. Such epi-Gd2O3 layers exhibited significant lower leakage currents compared to the commonly obtained epitaxial layers with two orthogonal domains. For capacitance equivalent thicknesses below 1 nm, this differences disappear, indicating that for ultrathin layers direct tunneling becomes dominating.
{"title":"Growth of epitaxial lanthanide oxide based gate dielectrics","authors":"H. Osten, A. Laha, E. Bugiel, D. Schwendt, A. Fissel","doi":"10.1109/ICSCS.2009.5414212","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5414212","url":null,"abstract":"Many materials systems are currently under consideration as potential replacements for SiO2 as the gate dielectric material for sub-0.1 µm CMOS technology. We present results for crystalline gadolinium oxides on silicon in the cubic bixbyite structure grown by solid source molecular beam epitaxy. On Si(100), crystalline Gd2O3 grows usually as (110)-oriented domains, with two orthogonal in-plane orientations. Layers grown under best vacuum conditions often exhibit poor dielectric properties due to the formation of crystalline interfacial silicide inclusions. Additional oxygen supply during growth improves the dielectric properties significantly. Layers grown by an optimized MBE process display a sufficiently high-K value to achieve equivalent oxide thickness values ≪ 1 nm, combined with ultra-low leakage current densities, good reliability, and high electrical breakdown voltage. A variety of MOS capacitors and field effect transistors has been fabricated based on these layers. Efficient manipulation of Si(100) 4° miscut substrate surfaces can lead to single domain epitaxial Gd2O3 layer. Such epi-Gd2O3 layers exhibited significant lower leakage currents compared to the commonly obtained epitaxial layers with two orthogonal domains. For capacitance equivalent thicknesses below 1 nm, this differences disappear, indicating that for ultrathin layers direct tunneling becomes dominating.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"2021 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126707682","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412620
Zhiwei Wang, M. Zaki, S. Tahar
One of the challenges for the verification of analog and mixed signal (AMS) designs is the stochastic behavior associated. In this paper, we propose a runtime verification approach to verify the statistical property of the AMS design. The methodology is based on the combination of the statistical method and Mont Carlo simulation. The verification procedure produces confidence level and error margin that provide the tolerance and accuracy for the verification results. We apply the proposed methodology to study the jitter property of a PLL design.
{"title":"Statistical runtime verification of analog and mixed signal designs","authors":"Zhiwei Wang, M. Zaki, S. Tahar","doi":"10.1109/ICSCS.2009.5412620","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412620","url":null,"abstract":"One of the challenges for the verification of analog and mixed signal (AMS) designs is the stochastic behavior associated. In this paper, we propose a runtime verification approach to verify the statistical property of the AMS design. The methodology is based on the combination of the statistical method and Mont Carlo simulation. The verification procedure produces confidence level and error margin that provide the tolerance and accuracy for the verification results. We apply the proposed methodology to study the jitter property of a PLL design.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121458023","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412536
D. Zaltni, M. Abdelkrim, M. Ghanes, J. Barbot
The current problems to successfully apply sensorless control techniques for Permanent Magnet Synchronous Motor (PMSM) are the existence of operating conditions for which the observer performance is remarkably deteriorated. This is due to difficulties in estimating correctly the rotor position at low speed. The failure of sensor-less schemes in some particular operating conditions has been always recognized in experimental settings. However, there are no sufficient theoretical observability analysis for the PMSM. In the literature, only the sufficient observability condition has been presented. Therefore, the current work is aimed specially to necessary observability condition analysis. Thus, we give here the necessary and sufficient states observability condition for the PMSM. An example is presented to illustrate the results.
{"title":"Observability analysis of PMSM","authors":"D. Zaltni, M. Abdelkrim, M. Ghanes, J. Barbot","doi":"10.1109/ICSCS.2009.5412536","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412536","url":null,"abstract":"The current problems to successfully apply sensorless control techniques for Permanent Magnet Synchronous Motor (PMSM) are the existence of operating conditions for which the observer performance is remarkably deteriorated. This is due to difficulties in estimating correctly the rotor position at low speed. The failure of sensor-less schemes in some particular operating conditions has been always recognized in experimental settings. However, there are no sufficient theoretical observability analysis for the PMSM. In the literature, only the sufficient observability condition has been presented. Therefore, the current work is aimed specially to necessary observability condition analysis. Thus, we give here the necessary and sufficient states observability condition for the PMSM. An example is presented to illustrate the results.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126296527","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412561
T. Bentrcia, F. Djeffal, M. Abdi, M. Chahdi, N. Boukhennoufa
There is no doubt that nanoelectronics based applications are the workhorse of the next industrial revolution, such importance has induced an accelerated research towards novel models governing behavior aspects of nanoscale components. Despite the proved advantages of GCGS DG MOSFET's topology, challenges continue to occur particularly concerning from a part model's accuracy and from another part reliability of new invented devices. This paper explores the surface -potential -based approach to derive an analytical threshold voltage model for nanoscale GCGS DG MOSFET at low drain-source voltage. Our obtained results showed considerable improvement compared to conventional DG MOSFETs. Followed steps presented herein may provide guidance and orientation needed for meaningful reliability measurements related to immunity of nanoscale DG MOSFETs against the hot-carrier degradation effects.
{"title":"An accurate two dimensional threshold voltage model for nanoscale GCGS DG MOSFET including traps effects","authors":"T. Bentrcia, F. Djeffal, M. Abdi, M. Chahdi, N. Boukhennoufa","doi":"10.1109/ICSCS.2009.5412561","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412561","url":null,"abstract":"There is no doubt that nanoelectronics based applications are the workhorse of the next industrial revolution, such importance has induced an accelerated research towards novel models governing behavior aspects of nanoscale components. Despite the proved advantages of GCGS DG MOSFET's topology, challenges continue to occur particularly concerning from a part model's accuracy and from another part reliability of new invented devices. This paper explores the surface -potential -based approach to derive an analytical threshold voltage model for nanoscale GCGS DG MOSFET at low drain-source voltage. Our obtained results showed considerable improvement compared to conventional DG MOSFETs. Followed steps presented herein may provide guidance and orientation needed for meaningful reliability measurements related to immunity of nanoscale DG MOSFETs against the hot-carrier degradation effects.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122281953","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412689
M. Laaraiedh, S. Avrillon, B. Uguen
In this paper, the problem of uncertainty on reference nodes positions is addressed in the context of hybrid data fusion techniques for localization. This problem arises in B3G networks where different location-dependent observables come from heterogeneous Radio Access Networks (RAN) leading to different levels of uncertainty on both ranges and anchor nodes positions. We assume a Gaussian model on the node position error as well as on the ranging error. We derive novel Maximum Likelihood based location estimator which considers these two sources of uncertainty. The performances of this new estimator is then compared to the ML estimator which does not consider erroneous reference nodes positions. Monte Carlo simulations show that the proposed estimator achieves better performances especially in the context of short range positioning.
{"title":"Exploiting the imperfect knowledge of reference nodes positions in range based positioning systems","authors":"M. Laaraiedh, S. Avrillon, B. Uguen","doi":"10.1109/ICSCS.2009.5412689","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412689","url":null,"abstract":"In this paper, the problem of uncertainty on reference nodes positions is addressed in the context of hybrid data fusion techniques for localization. This problem arises in B3G networks where different location-dependent observables come from heterogeneous Radio Access Networks (RAN) leading to different levels of uncertainty on both ranges and anchor nodes positions. We assume a Gaussian model on the node position error as well as on the ranging error. We derive novel Maximum Likelihood based location estimator which considers these two sources of uncertainty. The performances of this new estimator is then compared to the ML estimator which does not consider erroneous reference nodes positions. Monte Carlo simulations show that the proposed estimator achieves better performances especially in the context of short range positioning.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114076559","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 : 2009-11-01DOI: 10.1109/ICSCS.2009.5412600
V. Maingot, R. Leveugle
The robustness of a chip designed for security-related applications depends on its capability to globally resist to various types of attacks. This paper deals with protections against non invasive or semi invasive attacks. The two main categories are attacks based on power consumption (either by monitoring the current, e.g. DPA, or by monitoring the electromagnetic emissions, i.e. EMA) and attacks based on the injection of faults during the application execution (DFA). Information redundancy is often proposed as a basis for countermeasures against DFA. This paper discusses the influence of the choice of the code on the global robustness of the circuit. The study is focused on the evaluation of the sensitivity to DPA of several protected versions of an AES circuit.
{"title":"Influence of error detecting or correcting codes on the sensitivity to DPA of an AES S-box","authors":"V. Maingot, R. Leveugle","doi":"10.1109/ICSCS.2009.5412600","DOIUrl":"https://doi.org/10.1109/ICSCS.2009.5412600","url":null,"abstract":"The robustness of a chip designed for security-related applications depends on its capability to globally resist to various types of attacks. This paper deals with protections against non invasive or semi invasive attacks. The two main categories are attacks based on power consumption (either by monitoring the current, e.g. DPA, or by monitoring the electromagnetic emissions, i.e. EMA) and attacks based on the injection of faults during the application execution (DFA). Information redundancy is often proposed as a basis for countermeasures against DFA. This paper discusses the influence of the choice of the code on the global robustness of the circuit. The study is focused on the evaluation of the sensitivity to DPA of several protected versions of an AES circuit.","PeriodicalId":126072,"journal":{"name":"2009 3rd International Conference on Signals, Circuits and Systems (SCS)","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122433170","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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