With growing concerns about environmental pollution and a possible energy shortage, great efforts have been taken by the governments around the world to implement renewable energy programs, based mainly on wind power, solar energy, small hydro-electric power, etc. With improving techniques, reducing costs and low environmental impact, wind energy seems certain to play a major part in the world's energy future. Due to its many advantages such as the improved power quality, high energy efficiency and controllability, etc., the variable speed wind turbine using a double-output induction generator (DOIG) is becoming a popular concept and thus the modeling of the DOIG based wind turbine becomes an interesting research topic. As the wind power penetration continually increases, power utilities concerns are shifting focus from the power quality issue to the stability problem caused by the wind power connection. In such cases, it becomes important to consider the wind power impact properly in the power system planning and operation. Unfortunately, few power system analysis tools have included wind turbine models such as have been developed for traditional Power generators. The paper develops analytical steady-state and dynamic models to provide this insight and correlates the operating performance of DOIG for wind energy conversion systems using MATLAB-Simulink environment. This paper considers a grid-connected system; a further paper will describe a stand-alone system.
{"title":"Performance of Double-Output Induction Generator for Wind Energy Conversion Systems","authors":"B. Babu, K. Mohanty, C. Poongothai","doi":"10.1109/ICETET.2008.185","DOIUrl":"https://doi.org/10.1109/ICETET.2008.185","url":null,"abstract":"With growing concerns about environmental pollution and a possible energy shortage, great efforts have been taken by the governments around the world to implement renewable energy programs, based mainly on wind power, solar energy, small hydro-electric power, etc. With improving techniques, reducing costs and low environmental impact, wind energy seems certain to play a major part in the world's energy future. Due to its many advantages such as the improved power quality, high energy efficiency and controllability, etc., the variable speed wind turbine using a double-output induction generator (DOIG) is becoming a popular concept and thus the modeling of the DOIG based wind turbine becomes an interesting research topic. As the wind power penetration continually increases, power utilities concerns are shifting focus from the power quality issue to the stability problem caused by the wind power connection. In such cases, it becomes important to consider the wind power impact properly in the power system planning and operation. Unfortunately, few power system analysis tools have included wind turbine models such as have been developed for traditional Power generators. The paper develops analytical steady-state and dynamic models to provide this insight and correlates the operating performance of DOIG for wind energy conversion systems using MATLAB-Simulink environment. This paper considers a grid-connected system; a further paper will describe a stand-alone system.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124121341","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}
R. Senthilkumar, A. Kannan, K. Hariharan, N. Harishankar, G. P. Aravindan, R. Muthuraj
We propose a method for building a constraint validator from a given set of schema for a structured XML document. The validator checks for various relationships existing between the documents such as containment, intra and inter relationship. Thus generating a set of rules, this is used by the forthcoming operation on the XML database. The constraint validator checks for integrity, referential integrity, relative, absolute and value based constraints on the single, the intra and inter document database. The validator obtained by our method is used not only for checking the correctness of the existing XML document but also for incrementally validating updates over this document. The validator maintains the consistency of XML data after update operations, which can be classified into insertion, deletion and replacement. In this way both the static and incremental constraints checking are performed. The experimental results generated from the real data reveal that the algorithm works well in practice.
{"title":"Validating Constraints for Inter and Intra Relationships in XML Structured Document","authors":"R. Senthilkumar, A. Kannan, K. Hariharan, N. Harishankar, G. P. Aravindan, R. Muthuraj","doi":"10.1109/ICETET.2008.218","DOIUrl":"https://doi.org/10.1109/ICETET.2008.218","url":null,"abstract":"We propose a method for building a constraint validator from a given set of schema for a structured XML document. The validator checks for various relationships existing between the documents such as containment, intra and inter relationship. Thus generating a set of rules, this is used by the forthcoming operation on the XML database. The constraint validator checks for integrity, referential integrity, relative, absolute and value based constraints on the single, the intra and inter document database. The validator obtained by our method is used not only for checking the correctness of the existing XML document but also for incrementally validating updates over this document. The validator maintains the consistency of XML data after update operations, which can be classified into insertion, deletion and replacement. In this way both the static and incremental constraints checking are performed. The experimental results generated from the real data reveal that the algorithm works well in practice.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123516153","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}
Among all control methods for induction motor drives, Direct Torque Control (DTC) seems to be particularly interesting being independent of machine rotor parameters and requiring no speed or position sensors. The DTC scheme is characterized by the absence of PI regulators, coordinate transformations, current regulators and PWM signals generators. In spite of its simplicity, DTC allows a good torque control in steady state and transient operating conditions to be obtained. This paper is aimed to analyze DTC principles, the strategies and the problems related to its implementation and the possible improvements using Space Vector Pulse Width Modulation (SVPWM). In SVPWM for each sampling period the switching instants of different space vectors are determined to reduce torque ripple. The time durations of two adjacent voltage space vectors and the corresponding zerovoltage space vectors are determined in this method depending on maximum and average switching frequency, allowable for the switching devices in the three phase inverter. Simulation studies have been carried out for different operating conditions of the drive system. The results have been presented and compared with those of the conventional method.
{"title":"High Performance Direct Torque Controlled Induction Motor Drive for Adjustable Speed Drive Applications","authors":"B. Babu, C. Poongothai","doi":"10.1109/ICETET.2008.171","DOIUrl":"https://doi.org/10.1109/ICETET.2008.171","url":null,"abstract":"Among all control methods for induction motor drives, Direct Torque Control (DTC) seems to be particularly interesting being independent of machine rotor parameters and requiring no speed or position sensors. The DTC scheme is characterized by the absence of PI regulators, coordinate transformations, current regulators and PWM signals generators. In spite of its simplicity, DTC allows a good torque control in steady state and transient operating conditions to be obtained. This paper is aimed to analyze DTC principles, the strategies and the problems related to its implementation and the possible improvements using Space Vector Pulse Width Modulation (SVPWM). In SVPWM for each sampling period the switching instants of different space vectors are determined to reduce torque ripple. The time durations of two adjacent voltage space vectors and the corresponding zerovoltage space vectors are determined in this method depending on maximum and average switching frequency, allowable for the switching devices in the three phase inverter. Simulation studies have been carried out for different operating conditions of the drive system. The results have been presented and compared with those of the conventional method.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123653477","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}
Adiabatic switching techniques based on energy recovery principle are one of the innovative solutions at circuit and logic level to achieve reduction in power. Many researchers had taken adder as a benchmark circuit but advantage of adiabatic can be taken only for a large digital circuit. Barrel shifter is an important block in the processor design and not much effort has been done to minimize itpsilas power dissipation. A barrel shifter needs nlog2n MUX for n-bit shifting and therefore designing a MUX for low power to use it as a repetitive block in the barrel shifter will considerably reduce the simulation time. This paper compares conventional CMOS based design with adiabatic All the circuits are designed using cell based design approach and 180 nm device size in Cadence. The outcome of this research work will provide guidelines for designing barrel shifter using ultra low power MUX .
{"title":"Low Power 2:1 MUX for Barrel Shifter","authors":"P. Khandekar, S. Subbaraman","doi":"10.1109/ICETET.2008.47","DOIUrl":"https://doi.org/10.1109/ICETET.2008.47","url":null,"abstract":"Adiabatic switching techniques based on energy recovery principle are one of the innovative solutions at circuit and logic level to achieve reduction in power. Many researchers had taken adder as a benchmark circuit but advantage of adiabatic can be taken only for a large digital circuit. Barrel shifter is an important block in the processor design and not much effort has been done to minimize itpsilas power dissipation. A barrel shifter needs nlog2n MUX for n-bit shifting and therefore designing a MUX for low power to use it as a repetitive block in the barrel shifter will considerably reduce the simulation time. This paper compares conventional CMOS based design with adiabatic All the circuits are designed using cell based design approach and 180 nm device size in Cadence. The outcome of this research work will provide guidelines for designing barrel shifter using ultra low power MUX .","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122832420","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}
This study deals with the stochastic free vibration response of a laminated composite plate resting on a elastic foundation subjected to a temperature loading with uncertain material properties. The material properties are modeled as independent basic random variables. The temperature field considered is assumed to be a uniform distribution over the plate surface and through the plate thickness. The material properties are assumed to be independent of temperature. Based on the higher order deformation theory, C0 finite element method is employed to derive the eigen value problems in term of fundamental frequency. A mean-centered first order perturbation technique (FOPT) is adopted to evaluate the mean and standard derivation of the fundamental frequency with all edges simply supported boundary conditions. The effects of foundation parameters on the critical temperature are analyzed. The results have been validated with independent Monte Carlo simulation (MCS) and those available in the literature.
{"title":"Stochastic Thermal Free Vibration Response of Laminated Composite Plates Resting on Elastic Foundation with Uncertain Material Properties","authors":"A. Lal, Mihir V. Tadvi, R. Kumar","doi":"10.1109/ICETET.2008.258","DOIUrl":"https://doi.org/10.1109/ICETET.2008.258","url":null,"abstract":"This study deals with the stochastic free vibration response of a laminated composite plate resting on a elastic foundation subjected to a temperature loading with uncertain material properties. The material properties are modeled as independent basic random variables. The temperature field considered is assumed to be a uniform distribution over the plate surface and through the plate thickness. The material properties are assumed to be independent of temperature. Based on the higher order deformation theory, C0 finite element method is employed to derive the eigen value problems in term of fundamental frequency. A mean-centered first order perturbation technique (FOPT) is adopted to evaluate the mean and standard derivation of the fundamental frequency with all edges simply supported boundary conditions. The effects of foundation parameters on the critical temperature are analyzed. The results have been validated with independent Monte Carlo simulation (MCS) and those available in the literature.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122109833","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}
This paper presents a genetic algorithm approach to solve the "map colour problem". The map colour problem states that given any plane separated into regions, such as a political map of the states of a country, the regions may be coloured using two colours in such a way that no two adjacent regions receive the same colour. In this paper I have used genetic algorithm to find the solution for this kind of problem. Genetic algorithms are being used extensively in optimization problem as an alternative to traditional heuristics. It is an appealing idea that the natural concepts of evolution may be borrowed for use as a computational optimization technique and the result is "genetic algorithm", which is based on the principle "survival of the fittest" given by "Darvin".. I have tried to show that genetic algorithm is an alternative solution for those problems where conventional deterministic methods are not able to provide the optimal solution.
{"title":"A Novel Genetic Algorithm Approach to Solve Map Colour Problem","authors":"Anand Kumar","doi":"10.1109/ICETET.2008.82","DOIUrl":"https://doi.org/10.1109/ICETET.2008.82","url":null,"abstract":"This paper presents a genetic algorithm approach to solve the \"map colour problem\". The map colour problem states that given any plane separated into regions, such as a political map of the states of a country, the regions may be coloured using two colours in such a way that no two adjacent regions receive the same colour. In this paper I have used genetic algorithm to find the solution for this kind of problem. Genetic algorithms are being used extensively in optimization problem as an alternative to traditional heuristics. It is an appealing idea that the natural concepts of evolution may be borrowed for use as a computational optimization technique and the result is \"genetic algorithm\", which is based on the principle \"survival of the fittest\" given by \"Darvin\".. I have tried to show that genetic algorithm is an alternative solution for those problems where conventional deterministic methods are not able to provide the optimal solution.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123838401","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}
S. Gupta, Anand Gupta, Renu Damor, Vikram Goyal, Sangeeta Sabharwal
Honeypots have been studied in the network domain for detection and information collection against external threats in the past few years. They lure a potential attacker by simulating resources having vulnerabilities and observing the behavior of a potential attacker to identify him before a damaging attack takes place. A lot of work has been done in the area of privacy and security in databases. Though the number of attacks and complexity for database attacks are increasing day by day, there has been no attempt to design honeypots for privacy enforcing databases. The use of honeypots for databases would help in confirming the suspicion (malafide intention) of a suspicious user without leaking the target information (information which would fulfill the malafide intention) to the attacker. We propose a framework for database honeypots for certain types of attacks in privacy context. The proposed honeypots for databases are termed as context honeypots.
{"title":"Context Honeypot: A Framework for Anticipatory Privacy Violation","authors":"S. Gupta, Anand Gupta, Renu Damor, Vikram Goyal, Sangeeta Sabharwal","doi":"10.1109/ICETET.2008.26","DOIUrl":"https://doi.org/10.1109/ICETET.2008.26","url":null,"abstract":"Honeypots have been studied in the network domain for detection and information collection against external threats in the past few years. They lure a potential attacker by simulating resources having vulnerabilities and observing the behavior of a potential attacker to identify him before a damaging attack takes place. A lot of work has been done in the area of privacy and security in databases. Though the number of attacks and complexity for database attacks are increasing day by day, there has been no attempt to design honeypots for privacy enforcing databases. The use of honeypots for databases would help in confirming the suspicion (malafide intention) of a suspicious user without leaking the target information (information which would fulfill the malafide intention) to the attacker. We propose a framework for database honeypots for certain types of attacks in privacy context. The proposed honeypots for databases are termed as context honeypots.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125523075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, a fuzzy gain scheduled proportional and integral (FGPI) controller was developed to regulate and to improve the frequency deviation in a two-area electrical interconnected power system. Also, a conventional proportional and integral (PI), and a fuzzy logic (FL), controllers were used to control the same power system for the performance comparison. Two performance criteria were utilized for the comparison. First, settling times and overshoots of the frequency deviation were compared. Later, the absolute error integral analysis method was calculated to compare all the controllers. The Simulation results show that the FGPI controller developed in this study performs better than the other controllers with respect to the settling time and overshoot, and absolute error integral of the frequency deviation.
{"title":"Two Area Load Frequency Control with Fuzzy Gain Scheduling of PI Controller","authors":"A. Sreenath, Y. Atre, D. Patil","doi":"10.1109/ICETET.2008.255","DOIUrl":"https://doi.org/10.1109/ICETET.2008.255","url":null,"abstract":"In this paper, a fuzzy gain scheduled proportional and integral (FGPI) controller was developed to regulate and to improve the frequency deviation in a two-area electrical interconnected power system. Also, a conventional proportional and integral (PI), and a fuzzy logic (FL), controllers were used to control the same power system for the performance comparison. Two performance criteria were utilized for the comparison. First, settling times and overshoots of the frequency deviation were compared. Later, the absolute error integral analysis method was calculated to compare all the controllers. The Simulation results show that the FGPI controller developed in this study performs better than the other controllers with respect to the settling time and overshoot, and absolute error integral of the frequency deviation.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131920984","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}
The international standard IEEE 802.11 wireless LAN protocol is a popular standard for wireless local area networks. Its medium access control layer (MAC) is a carrier sense multiple access with collision avoidance (CSMA/CA) design, although collisions cannot always be prevented, randomized exponential backoff rule is used in the retransmission scheme to minimize the likelihood of repeated collisions. To work around this problem, we identify state transition of the protocol that can be used to simplify the models and make verification feasible. This paper explains the state transition model of two way handshake mechanism of IEEE 802.11 standard for MAC DCF. Using these observations, a time variant generalized state transition model for channel, sender and destination station has been described. The proposed model has been validated using network simulator ns-2.
{"title":"A Finite State Model for IEEE 802.11 Wireless LAN MAC DCF","authors":"D. K. Puthal, B. Sahoo","doi":"10.1109/ICETET.2008.62","DOIUrl":"https://doi.org/10.1109/ICETET.2008.62","url":null,"abstract":"The international standard IEEE 802.11 wireless LAN protocol is a popular standard for wireless local area networks. Its medium access control layer (MAC) is a carrier sense multiple access with collision avoidance (CSMA/CA) design, although collisions cannot always be prevented, randomized exponential backoff rule is used in the retransmission scheme to minimize the likelihood of repeated collisions. To work around this problem, we identify state transition of the protocol that can be used to simplify the models and make verification feasible. This paper explains the state transition model of two way handshake mechanism of IEEE 802.11 standard for MAC DCF. Using these observations, a time variant generalized state transition model for channel, sender and destination station has been described. The proposed model has been validated using network simulator ns-2.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"1999 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128259473","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}
The multidimensional knapsack problem (MKP), which is a generalization of the 0-1 simple Knapsack problem, is one of the classical NP-hard problems in operations research having a number of engineering applications. Several exact as well as heuristic algorithms are available in literature for its solution. In this paper, we propose a new particle swarm optimization (PSO) algorithm namely socio-cognitive particle swarm optimization (SCPSO) for solving the MKP. Comparing with the basic binary particle swarm optimization (BPSO), this improved algorithm introduces the distance between gbest and pbest as a new velocity update equation which maintains the diversity in the swarm and makes it more effective and efficient in solving MKP. We present computational experiments with various data instances for fine tuning of parameters of SCPSO and to validate our ideas and demonstrate the efficiency of the proposed algorithm.
{"title":"A Socio-Cognitive Particle Swarm Optimization for Multi-Dimensional Knapsack Problem","authors":"Kusum Deep, Jagdish Chand Bansal","doi":"10.1109/ICETET.2008.163","DOIUrl":"https://doi.org/10.1109/ICETET.2008.163","url":null,"abstract":"The multidimensional knapsack problem (MKP), which is a generalization of the 0-1 simple Knapsack problem, is one of the classical NP-hard problems in operations research having a number of engineering applications. Several exact as well as heuristic algorithms are available in literature for its solution. In this paper, we propose a new particle swarm optimization (PSO) algorithm namely socio-cognitive particle swarm optimization (SCPSO) for solving the MKP. Comparing with the basic binary particle swarm optimization (BPSO), this improved algorithm introduces the distance between gbest and pbest as a new velocity update equation which maintains the diversity in the swarm and makes it more effective and efficient in solving MKP. We present computational experiments with various data instances for fine tuning of parameters of SCPSO and to validate our ideas and demonstrate the efficiency of the proposed algorithm.","PeriodicalId":269929,"journal":{"name":"2008 First International Conference on Emerging Trends in Engineering and Technology","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128323950","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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