Pub Date : 2009-06-11DOI: 10.1109/RAST.2009.5158207
H. Akah, A. Kamel, H. El-Hennawy
This paper studies the feasibility of using adaptive pulse shaping CP-OFDM in remote sensing satellites. A set of pulse shapes were generated using genetic algorithm that minimizes the mean square error of the timing offset estimator. These pulse shapes were used to train function approximation neural networks. Such neural networks make the use of adaptive pulse shaping in OFDM systems feasible. Results from neural networks simulation, which have shown the ability of neural networks to fulfill such function for a two ray model channels, are presented.
{"title":"Adaptive pulse shaped CP-OFDM for remote sensing satellites","authors":"H. Akah, A. Kamel, H. El-Hennawy","doi":"10.1109/RAST.2009.5158207","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158207","url":null,"abstract":"This paper studies the feasibility of using adaptive pulse shaping CP-OFDM in remote sensing satellites. A set of pulse shapes were generated using genetic algorithm that minimizes the mean square error of the timing offset estimator. These pulse shapes were used to train function approximation neural networks. Such neural networks make the use of adaptive pulse shaping in OFDM systems feasible. Results from neural networks simulation, which have shown the ability of neural networks to fulfill such function for a two ray model channels, are presented.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126549186","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158198
Ehsan A. Tahmasebi, H. Karimi, R. Ebrahimi
Conceptual design algorithm of hybrid rocket motor with solid fuel and liquid oxidizer is investigated in this study. Hybrid chemical rocket propulsion is presently of interest due to reduced system complexity compared to classical chemical propulsion systems. A computational code for conceptual design and performance modeling of hybrid propulsion motor developed. Results are validating with experimental test results.
{"title":"Conceptual design and performancenumerical modeling of hybrid propulsion motor","authors":"Ehsan A. Tahmasebi, H. Karimi, R. Ebrahimi","doi":"10.1109/RAST.2009.5158198","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158198","url":null,"abstract":"Conceptual design algorithm of hybrid rocket motor with solid fuel and liquid oxidizer is investigated in this study. Hybrid chemical rocket propulsion is presently of interest due to reduced system complexity compared to classical chemical propulsion systems. A computational code for conceptual design and performance modeling of hybrid propulsion motor developed. Results are validating with experimental test results.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"185 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133940841","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158185
O. Kilit, Alper Yontar
A rough terrain adaptive rover using a novel suspension system with extremely high mobility is described. By using a multi stage type of a well-known bogie system, a rover gains a high level of adaptability to rough terrain. A novel method to model the rover path which doesn't require any surface modeling tool of rough terrain is represented. Two tilting angles - measured about both longitudinal and lateral axes of the rover body - are taken into consideration as stability criteria. Through the computer simulation, the kinematics model of the mobile robot moving on a randomly generated rough terrain is verified.
{"title":"Stability of a new mars rover with multi-stage bogie mechanism","authors":"O. Kilit, Alper Yontar","doi":"10.1109/RAST.2009.5158185","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158185","url":null,"abstract":"A rough terrain adaptive rover using a novel suspension system with extremely high mobility is described. By using a multi stage type of a well-known bogie system, a rover gains a high level of adaptability to rough terrain. A novel method to model the rover path which doesn't require any surface modeling tool of rough terrain is represented. Two tilting angles - measured about both longitudinal and lateral axes of the rover body - are taken into consideration as stability criteria. Through the computer simulation, the kinematics model of the mobile robot moving on a randomly generated rough terrain is verified.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"283 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133975362","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158274
Secil Karatay, F. Arıkan, O. Arikan
The ionosphere can be characterized with its electron density distribution which is a complex function of spatial and temporal variations, geomagnetic, solar and seismic activity. An important measurable quantity about the electron density is the Total Electron Content (TEC) which is proportional to the total number of electrons on a line crossing the atmosphere. TEC measurements enable monitoring variations in the space weather. Global Positioning System (GPS) and the network of world-wide receivers provide a cost-effective solution in estimating TEC over a significant proportion of global land mass. In this study, five earthquakes between 2003–2008 that occurred in Japan with different seismic properties, and the China earthquake in May 2008 are investigated. The TEC data set is investigated by using the Kullback-Leibler Divergence (KLI), Kullback-Leibler Distance (KLD) and L2-Norm (L2N) which are used for the first time in the literature in this context and Cross Correlation Function (CCF) which is used in the literature before for quiet day period (QDP), disturbed day period (DDP), periods of 15 days before a strong earthquake (BE) and after the earthquake (AE). In summary, it is observed that the CCF, KLD and L2N between the neighbouring GPS stations cannot be used as a definitive earthquake precursor due to the complicated nature of earthquakes and various uncontrolled parameters that effect the behavior of TEC such as distance to the earthquake epicenter, distance between the stations, depth of the earthquake, strength of the earthquake and tectonic structure of the earthquake. KLD, KLI and L2N are used for the first time in literature for the investigation of earthquake precursor for the first time in literature and the extensive study results indicate that for more reliable estimates further space-time TEC analysis is necessary over a denser GPS network in the earthquake zones.
{"title":"Investigation of hourly and daily patterns for lithosphere-ionosphere coupling before strong earthquakes","authors":"Secil Karatay, F. Arıkan, O. Arikan","doi":"10.1109/RAST.2009.5158274","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158274","url":null,"abstract":"The ionosphere can be characterized with its electron density distribution which is a complex function of spatial and temporal variations, geomagnetic, solar and seismic activity. An important measurable quantity about the electron density is the Total Electron Content (TEC) which is proportional to the total number of electrons on a line crossing the atmosphere. TEC measurements enable monitoring variations in the space weather. Global Positioning System (GPS) and the network of world-wide receivers provide a cost-effective solution in estimating TEC over a significant proportion of global land mass. In this study, five earthquakes between 2003–2008 that occurred in Japan with different seismic properties, and the China earthquake in May 2008 are investigated. The TEC data set is investigated by using the Kullback-Leibler Divergence (KLI), Kullback-Leibler Distance (KLD) and L2-Norm (L2N) which are used for the first time in the literature in this context and Cross Correlation Function (CCF) which is used in the literature before for quiet day period (QDP), disturbed day period (DDP), periods of 15 days before a strong earthquake (BE) and after the earthquake (AE). In summary, it is observed that the CCF, KLD and L2N between the neighbouring GPS stations cannot be used as a definitive earthquake precursor due to the complicated nature of earthquakes and various uncontrolled parameters that effect the behavior of TEC such as distance to the earthquake epicenter, distance between the stations, depth of the earthquake, strength of the earthquake and tectonic structure of the earthquake. KLD, KLI and L2N are used for the first time in literature for the investigation of earthquake precursor for the first time in literature and the extensive study results indicate that for more reliable estimates further space-time TEC analysis is necessary over a denser GPS network in the earthquake zones.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134044892","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158295
E. Oland, Alexander Aas, Tor Marius Steihaug, S. V. Mathisen, Frank R. Vedal
In this paper we present a design methodology for attitude determination and control systems for picosatellites. It is based on the ECSS documentations and shows through a practical example how the ECSS standard can be applied to a picosatellite project.
{"title":"A design guide for attitude determination and control systems for picosatellites","authors":"E. Oland, Alexander Aas, Tor Marius Steihaug, S. V. Mathisen, Frank R. Vedal","doi":"10.1109/RAST.2009.5158295","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158295","url":null,"abstract":"In this paper we present a design methodology for attitude determination and control systems for picosatellites. It is based on the ECSS documentations and shows through a practical example how the ECSS standard can be applied to a picosatellite project.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134147411","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158201
A. Pourrajabian, M. Bakhtiari, R. Ebrahimi, H. Karimi
In this study, to reduce the drag force, the nose shape of Launch Vehicle with determined flight conditions, is optimized. Two optimization methods are considered: binary genetic algorithm and response surface method. Since the value of drag coefficient is proportional to dynamic pressure, the objective function is based on minimization of drag coefficient in flight conditions which is corresponding to the maximum dynamic pressure. In order to evaluation of objective function, the aerodynamic prediction engineering code is used. The results of aerodynamic prediction code directly entered to binary genetic algorithm code and with common parameters of this algorithm like crossover, mutation and elitism, the optimization process is done. Moreover, the sensibility analysis of this algorithm respect to mutation parameter and size of population is analyzed and optimum values of them are obtained. Also, response Surface Method with quadratic model is considered. Some special points from domain of design variables are selected and corresponding drag coefficients for these points are calculated by aerodynamic prediction engineering code. Then, the appropriate second order surface is fitted to these points regarding to least square method. The results show that with optimum values of genetic algorithm parameters (rate of mutation and size of population); the algorithm converges rapidly with a few generations. In this case, the genetic algorithm only searches the 1.4% of solution space and then converged. Generally, the results show good agreement between two methods.
{"title":"Optimization of nose shape of Launch Vehicle using genetic algorithm and response surface methods","authors":"A. Pourrajabian, M. Bakhtiari, R. Ebrahimi, H. Karimi","doi":"10.1109/RAST.2009.5158201","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158201","url":null,"abstract":"In this study, to reduce the drag force, the nose shape of Launch Vehicle with determined flight conditions, is optimized. Two optimization methods are considered: binary genetic algorithm and response surface method. Since the value of drag coefficient is proportional to dynamic pressure, the objective function is based on minimization of drag coefficient in flight conditions which is corresponding to the maximum dynamic pressure. In order to evaluation of objective function, the aerodynamic prediction engineering code is used. The results of aerodynamic prediction code directly entered to binary genetic algorithm code and with common parameters of this algorithm like crossover, mutation and elitism, the optimization process is done. Moreover, the sensibility analysis of this algorithm respect to mutation parameter and size of population is analyzed and optimum values of them are obtained. Also, response Surface Method with quadratic model is considered. Some special points from domain of design variables are selected and corresponding drag coefficients for these points are calculated by aerodynamic prediction engineering code. Then, the appropriate second order surface is fitted to these points regarding to least square method. The results show that with optimum values of genetic algorithm parameters (rate of mutation and size of population); the algorithm converges rapidly with a few generations. In this case, the genetic algorithm only searches the 1.4% of solution space and then converged. Generally, the results show good agreement between two methods.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115863853","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158287
Serdar Ay, O. E. Vatandas, A. Hacioglu
In recent years, Stewart Platform Mechanism has been utilized extensively in applications which are vibration control and aligning optics of astronomical telescopes, satellite dish positioning, flight simulators, and so on requiring high precision, loading capacity, accuracy, rigidity and high velocity. However, the limited workspace, complex kinematic / kinetic solutions and singularities inside the workspace are the most important problems encountered with regard to this type of mechanisms. There are some parameters which affect significantly the workspace of Stewart Platform Mechanism. Some of these parameters are leg lengths, joint location angles and radius of joint location. Within this study, the effect of the radius of joint location of both moving platform and fixed platform on the workspace is investigated by calculating workspaces and comparing results for different radii of joint locations utilizing inverse kinematics technique.
{"title":"The effect of radius of joint location on workspace analysis of the 6-6 Stewart Platform Mechanism","authors":"Serdar Ay, O. E. Vatandas, A. Hacioglu","doi":"10.1109/RAST.2009.5158287","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158287","url":null,"abstract":"In recent years, Stewart Platform Mechanism has been utilized extensively in applications which are vibration control and aligning optics of astronomical telescopes, satellite dish positioning, flight simulators, and so on requiring high precision, loading capacity, accuracy, rigidity and high velocity. However, the limited workspace, complex kinematic / kinetic solutions and singularities inside the workspace are the most important problems encountered with regard to this type of mechanisms. There are some parameters which affect significantly the workspace of Stewart Platform Mechanism. Some of these parameters are leg lengths, joint location angles and radius of joint location. Within this study, the effect of the radius of joint location of both moving platform and fixed platform on the workspace is investigated by calculating workspaces and comparing results for different radii of joint locations utilizing inverse kinematics technique.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131376428","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158227
I. Bayir
Over the past decade the commercial remote sensing industry has experienced significant technological change and improved market penetration. New sensor Technologies in space systems offer new information capabilities.
{"title":"A glimpse to future commercial spy satellite systems","authors":"I. Bayir","doi":"10.1109/RAST.2009.5158227","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158227","url":null,"abstract":"Over the past decade the commercial remote sensing industry has experienced significant technological change and improved market penetration. New sensor Technologies in space systems offer new information capabilities.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124640648","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158195
F. Mingireanu
We present our research effort in the field of hybrid rocket motors. A computation model is presented together with results from a numerical algorithm based on the computation model. We present theoretical predictions for several hybrid rocket motors and compare the theoretical predictions with experimental measurements on those hybrid rocket motors. We also present several regression models to be used in hybrid rocket motors and evaluate each of them against experimental data provided by research groups worldwide. First section of the presentation focuses on hybrid rocket motor development.
{"title":"Hybrid rocket motor internal ballistic model and oxidizer dopping. Applications.","authors":"F. Mingireanu","doi":"10.1109/RAST.2009.5158195","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158195","url":null,"abstract":"We present our research effort in the field of hybrid rocket motors. A computation model is presented together with results from a numerical algorithm based on the computation model. We present theoretical predictions for several hybrid rocket motors and compare the theoretical predictions with experimental measurements on those hybrid rocket motors. We also present several regression models to be used in hybrid rocket motors and evaluate each of them against experimental data provided by research groups worldwide. First section of the presentation focuses on hybrid rocket motor development.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124144902","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 : 2009-06-11DOI: 10.1109/RAST.2009.5158219
Ma Libang, Niu Shuwen, Yang Lina, Li Yixin, L. Yonghua
Land use/cover change (LUCC) is one of the core contents of the global change research. As a unique ecological unit in arid and semi-arid area, oasis is a basic premise to maintain the existence and development of local people. In this paper, the rectangular area, where Dunhuang oasis locates, is chosen to study the dynamic change of LUCC over the last 20 years. Landsat5-TM images of 1987, 1996 and 2007 were interpreted by ArcGIS9.2 software. Based on field investigation, the land use type is classified into 6 classes (crop land, water wetland, high coverage grassland, moderate coverage grassland, low coverage grassland and non-vegetation area) to analyze the LUCC, which was showed by transfer matrix. The results showed that the vegetation-coverage was generally increasing over the last 20 years, which is more obvious in the latter 10 years. The area of artificial vegetation in crop land increased significantly by 38.67%. Among natural vegetation, the area of high coverage grassland increased by 83.94% while other four land type classes were decreased. The area of moderate and low coverage grassland decreased by 11.73% and 24.41% respectively. According to the transfer matrix of interpreted data, the conversions were occurred among 6 land use types. The main conversion types are as follows, conversion from low coverage grassland and non-vegetation area to crop land, moderate and low coverage grassland to high coverage grassland, and inter-conversion between low coverage grassland and non-vegetation area. The main reason of vegetation change is the expand use of water resources. Not only the area of irrigated farmland was increased, but also the area of high coverage grassland was enlarged benefiting from infiltration of the surface water in farmland.
{"title":"Dynamic analysis of land use/land cover change in Dunhuang oasis, China","authors":"Ma Libang, Niu Shuwen, Yang Lina, Li Yixin, L. Yonghua","doi":"10.1109/RAST.2009.5158219","DOIUrl":"https://doi.org/10.1109/RAST.2009.5158219","url":null,"abstract":"Land use/cover change (LUCC) is one of the core contents of the global change research. As a unique ecological unit in arid and semi-arid area, oasis is a basic premise to maintain the existence and development of local people. In this paper, the rectangular area, where Dunhuang oasis locates, is chosen to study the dynamic change of LUCC over the last 20 years. Landsat5-TM images of 1987, 1996 and 2007 were interpreted by ArcGIS9.2 software. Based on field investigation, the land use type is classified into 6 classes (crop land, water wetland, high coverage grassland, moderate coverage grassland, low coverage grassland and non-vegetation area) to analyze the LUCC, which was showed by transfer matrix. The results showed that the vegetation-coverage was generally increasing over the last 20 years, which is more obvious in the latter 10 years. The area of artificial vegetation in crop land increased significantly by 38.67%. Among natural vegetation, the area of high coverage grassland increased by 83.94% while other four land type classes were decreased. The area of moderate and low coverage grassland decreased by 11.73% and 24.41% respectively. According to the transfer matrix of interpreted data, the conversions were occurred among 6 land use types. The main conversion types are as follows, conversion from low coverage grassland and non-vegetation area to crop land, moderate and low coverage grassland to high coverage grassland, and inter-conversion between low coverage grassland and non-vegetation area. The main reason of vegetation change is the expand use of water resources. Not only the area of irrigated farmland was increased, but also the area of high coverage grassland was enlarged benefiting from infiltration of the surface water in farmland.","PeriodicalId":412236,"journal":{"name":"2009 4th International Conference on Recent Advances in Space Technologies","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125594908","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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