Pub Date : 2019-12-01DOI: 10.1109/ICC47138.2019.9123234
Anuj Tiwari, S. Devasia
This article addresses the rapid transfer of velocity-transition information through a robotic platoon, without the need for centralized communication. Such rapid propagation of information through a network is important since it can lead to cohesive maneuvers, which in turn aids in performance, e.g., to maintain smaller headway between the agents in the platoon. A challenge, however, is that in absence of centralized communication, each agent uses neighbor-based update laws, which tend to be diffusive in nature and lead to loss of cohesion in the overall response. The main contribution of this work is to use a Nesterov-type, accelerated-gradient-based approach to improve both the convergence and cohesion of a platoon’s response. An advantage is that the modified update law can be implemented using a delayed-self-reinforcement (DSR) method that does not require new information from the network nor any modification of the network connectivity. Additionally, the article presents conditions for stability as well as experimental results to illustrate the performance improvements.
{"title":"Cohesive Velocity Transitions in Robotic Platoons Using Nesterov-type Accelerated Delayed Self Reinforcement (A-DSR)","authors":"Anuj Tiwari, S. Devasia","doi":"10.1109/ICC47138.2019.9123234","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123234","url":null,"abstract":"This article addresses the rapid transfer of velocity-transition information through a robotic platoon, without the need for centralized communication. Such rapid propagation of information through a network is important since it can lead to cohesive maneuvers, which in turn aids in performance, e.g., to maintain smaller headway between the agents in the platoon. A challenge, however, is that in absence of centralized communication, each agent uses neighbor-based update laws, which tend to be diffusive in nature and lead to loss of cohesion in the overall response. The main contribution of this work is to use a Nesterov-type, accelerated-gradient-based approach to improve both the convergence and cohesion of a platoon’s response. An advantage is that the modified update law can be implemented using a delayed-self-reinforcement (DSR) method that does not require new information from the network nor any modification of the network connectivity. Additionally, the article presents conditions for stability as well as experimental results to illustrate the performance improvements.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131921480","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123170
Ranjana Singh, Surbhi Sharma, L. Giri, K. Mitra
Indole is produced when Escherichia Coli K12 is subjected to stress in a long duration mixed culture with Bacillus subtilis 168. Due to the therapeutic uses of Indole, a mathematical model of the mixed culture process underlying the growth and providing the optimal operating condition could prove immensely useful for the large scale production of Indole in industries. In this work, an experimental study has been conducted to study the long duration mixed culture effect on Escherichia Coli and Bacillus Subtilis in minimal media. Experimental investigation of individual growth profile of both the bacteria before and after the mixed culture is also conducted with glucose as substrate to analyze the effect of interaction. A computational strategy for identification of optimal unstructured model for mixed culture using hybrid optimization technique has been adopted. For modelling the mixed culture, dynamics of long duration passage experiment dynamic optimization technique has been implemented, which can be used to find optimal operating conditions. This work represents the first instance, where hybrid and dynamic optimization techniques have been applied for unstructured modeling and optimization of mixed culture, acting as a novel framework for optimal production of Indole at industrial scale and drug discovery.
{"title":"Dynamic optimization for Optimal production of Indole in a mixed culture","authors":"Ranjana Singh, Surbhi Sharma, L. Giri, K. Mitra","doi":"10.1109/ICC47138.2019.9123170","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123170","url":null,"abstract":"Indole is produced when Escherichia Coli K12 is subjected to stress in a long duration mixed culture with Bacillus subtilis 168. Due to the therapeutic uses of Indole, a mathematical model of the mixed culture process underlying the growth and providing the optimal operating condition could prove immensely useful for the large scale production of Indole in industries. In this work, an experimental study has been conducted to study the long duration mixed culture effect on Escherichia Coli and Bacillus Subtilis in minimal media. Experimental investigation of individual growth profile of both the bacteria before and after the mixed culture is also conducted with glucose as substrate to analyze the effect of interaction. A computational strategy for identification of optimal unstructured model for mixed culture using hybrid optimization technique has been adopted. For modelling the mixed culture, dynamics of long duration passage experiment dynamic optimization technique has been implemented, which can be used to find optimal operating conditions. This work represents the first instance, where hybrid and dynamic optimization techniques have been applied for unstructured modeling and optimization of mixed culture, acting as a novel framework for optimal production of Indole at industrial scale and drug discovery.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123416831","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123154
Kushal Chakrabarti, Nirupam Gupta, N. Chopra
This paper considers a distributed solution for a system of linear equations. The underlying peer-to-peer communication network is assumed to be undirected, however, the communication links are subject to potentially large but constant delays. We propose an algorithm that solves a distributed least-squares problem, which is equivalent to solving the system of linear equations. Effectively, the proposed algorithm is a pre-conditioned version of the traditional consensus-based distributed gradient descent (DGD) algorithm. We show that the accuracy of the solution obtained by the proposed algorithm is better than the DGD algorithm, especially when the system of linear equations is ill-conditioned.
{"title":"On Distributed Solution of Ill-Conditioned System of Linear Equations under Communication Delays","authors":"Kushal Chakrabarti, Nirupam Gupta, N. Chopra","doi":"10.1109/ICC47138.2019.9123154","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123154","url":null,"abstract":"This paper considers a distributed solution for a system of linear equations. The underlying peer-to-peer communication network is assumed to be undirected, however, the communication links are subject to potentially large but constant delays. We propose an algorithm that solves a distributed least-squares problem, which is equivalent to solving the system of linear equations. Effectively, the proposed algorithm is a pre-conditioned version of the traditional consensus-based distributed gradient descent (DGD) algorithm. We show that the accuracy of the solution obtained by the proposed algorithm is better than the DGD algorithm, especially when the system of linear equations is ill-conditioned.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"40 11","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114132046","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123231
S. Jebakumar, N. Kumar, A. Pashilkar
An automatic scheme for the flight envelope protection of fighter aircraft is developed to prevent departure due to loss of control. The scheme involves taking control away from the pilot some time prior to an impending departure. The automatic recovery system then puts the aircraft into a safe attitude for recovery. The stability of the recovery trajectory is analysed within the flight envelope of the aircraft. The analysis demonstrates that the phugoid mode become critical for the recovery from low speed. The specific energy is demonstrating to be a much simple way of handling low speed recovery problems compare to existing solutions available.In addition,a unique command path design has been incorporated to assist automatic low speed recovery. The scheme is illustrated using the database of a high performance fighter aircraft with multiple redundant controls.
{"title":"Flight Envelope Protection for a Fighter Aircraft","authors":"S. Jebakumar, N. Kumar, A. Pashilkar","doi":"10.1109/ICC47138.2019.9123231","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123231","url":null,"abstract":"An automatic scheme for the flight envelope protection of fighter aircraft is developed to prevent departure due to loss of control. The scheme involves taking control away from the pilot some time prior to an impending departure. The automatic recovery system then puts the aircraft into a safe attitude for recovery. The stability of the recovery trajectory is analysed within the flight envelope of the aircraft. The analysis demonstrates that the phugoid mode become critical for the recovery from low speed. The specific energy is demonstrating to be a much simple way of handling low speed recovery problems compare to existing solutions available.In addition,a unique command path design has been incorporated to assist automatic low speed recovery. The scheme is illustrated using the database of a high performance fighter aircraft with multiple redundant controls.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124700474","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123165
S. Sinha, U. Vaidya, Enoch Yeung
In this paper, we develop the concept of information transfer between the Borel-measurable sets for a dynamical system described by a measurable space and a non-singular transformation. The concept is based on how Shannon entropy is transferred between the measurable sets, as the dynamical system evolves. We show that the proposed definition of information transfer satisfies the usual notions of information transfer and causality, namely, zero transfer and transfer asymmetry. Furthermore, we show how the information transfer measure can be used to characterize ergodicity and mixing in dynamical systems. We also develop the computational methods for information transfer computation and apply the framework for optimal placement of actuators and sensors for control of non-equilibrium dynamics.
{"title":"On Information Transfer in Dynamical Systems with applications in Control of Non-equilibrium Dynamics","authors":"S. Sinha, U. Vaidya, Enoch Yeung","doi":"10.1109/ICC47138.2019.9123165","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123165","url":null,"abstract":"In this paper, we develop the concept of information transfer between the Borel-measurable sets for a dynamical system described by a measurable space and a non-singular transformation. The concept is based on how Shannon entropy is transferred between the measurable sets, as the dynamical system evolves. We show that the proposed definition of information transfer satisfies the usual notions of information transfer and causality, namely, zero transfer and transfer asymmetry. Furthermore, we show how the information transfer measure can be used to characterize ergodicity and mixing in dynamical systems. We also develop the computational methods for information transfer computation and apply the framework for optimal placement of actuators and sensors for control of non-equilibrium dynamics.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128261564","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123164
M. Mukherjee, Debasattam Pal
In this paper, we provide an implementable algorithm for computing solutions of a system of linear partial difference equations (pdes) with real constant coefficients having n independent variables and one dependent variable. An important consideration for explicitly solving a system of pdes lies in specifying the initial and/or boundary conditions. We assume that an initial condition set, in the form of a characteristic set, is provided along with the system of pdes. In such a scenario, we provide an algorithm, based on Gröbner basis, which explicitly computes the solution trajectory for the system of pdes at a specified point in the domain. The algorithm can be tested using any standard computer algebra package.
{"title":"Computation of solutions for an overdetermined system of partial difference equations","authors":"M. Mukherjee, Debasattam Pal","doi":"10.1109/ICC47138.2019.9123164","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123164","url":null,"abstract":"In this paper, we provide an implementable algorithm for computing solutions of a system of linear partial difference equations (pdes) with real constant coefficients having n independent variables and one dependent variable. An important consideration for explicitly solving a system of pdes lies in specifying the initial and/or boundary conditions. We assume that an initial condition set, in the form of a characteristic set, is provided along with the system of pdes. In such a scenario, we provide an algorithm, based on Gröbner basis, which explicitly computes the solution trajectory for the system of pdes at a specified point in the domain. The algorithm can be tested using any standard computer algebra package.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131722176","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123210
Justin Jacob, Sreya Das, N. Khaneja
Stabilization of linear time-invariant multi-inputmulti-output (LTI-MIMO) systems is presented distinctively and efficiently in this paper. The idea is to decouple the system state matrix depending on different inputs and outputs using the special canonical transformation proposed. Due to the decoupled form of the observer based controller system, it’s possible to use separate transformation for observer and controller design. Since the decoupled state matrix resembles the single-input-single-output (SISO) case, the generalized equation for the system is first obtained, and then it’s extended to the MIMO system. The computational complexity in getting the controller and observer gain matrix coefficients are further reduced due to the special form of gain matrices taken.
{"title":"A Concise Method of Pole Placement to Stabilize the Linear Time Invariant MIMO System","authors":"Justin Jacob, Sreya Das, N. Khaneja","doi":"10.1109/ICC47138.2019.9123210","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123210","url":null,"abstract":"Stabilization of linear time-invariant multi-inputmulti-output (LTI-MIMO) systems is presented distinctively and efficiently in this paper. The idea is to decouple the system state matrix depending on different inputs and outputs using the special canonical transformation proposed. Due to the decoupled form of the observer based controller system, it’s possible to use separate transformation for observer and controller design. Since the decoupled state matrix resembles the single-input-single-output (SISO) case, the generalized equation for the system is first obtained, and then it’s extended to the MIMO system. The computational complexity in getting the controller and observer gain matrix coefficients are further reduced due to the special form of gain matrices taken.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131771761","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123241
E. Butcher, Mohammad Maadani
Nonlinear control laws are proposed for consensus control of a multi-agent system of N heterogeneous rigid bodies in the framework of the tangent bundles TSO (3) and TSE (3) associated with Lie groups SO (3) and SE (3). The control objective is to stabilize the relative pose configurations with velocity synchronization of the rigid bodies which share their states according to a static communication topology. The feedback control design is conducted on the dynamic level in which masses and inertias are not negligible and uses the rotation matrix as opposed to various attitude parameterizations. Almost global asymptotic stability of the consensus subspace is demonstrated both analytically and through numerical simulations.
{"title":"Consensus Control of a Multi-Agent Rigid Body System on TSO(3)N and TSE(3)N","authors":"E. Butcher, Mohammad Maadani","doi":"10.1109/ICC47138.2019.9123241","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123241","url":null,"abstract":"Nonlinear control laws are proposed for consensus control of a multi-agent system of N heterogeneous rigid bodies in the framework of the tangent bundles TSO (3) and TSE (3) associated with Lie groups SO (3) and SE (3). The control objective is to stabilize the relative pose configurations with velocity synchronization of the rigid bodies which share their states according to a static communication topology. The feedback control design is conducted on the dynamic level in which masses and inertias are not negligible and uses the rotation matrix as opposed to various attitude parameterizations. Almost global asymptotic stability of the consensus subspace is demonstrated both analytically and through numerical simulations.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130955973","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123204
P. Ubare, Deepak D. Ingole, D. Sonawane
The maximum distance that can be traveled at a stretch is the major limitation of today’s electric vehicle (EV). This is due to the need for maximum current, torque, and, the total onboard energy storage, etc. The distance can be increased by efficiently using the available power resources. In this paper, we present a nonlinear model predictive control (NMPC) scheme for the control of brushless direct current (BLDC) motor in EV. A control-oriented nonlinear model of the BLDC motor with EV load is considered and used in the proposed NMPC scheme. The objective of the NMPC is to control the desired torque and speed of the motor by minimizing the energy with constraints on supplied current and maximum speed. The simulation results of BLDC motor control with EV and fixed mechanical load are presented. Further, the performance of NMPC is compared with the conventional direct torque control (DTC) scheme. Presented results show that NMPC improves energy savings by 19% in fixed-load and 13% with EV load as compared to DTC under provided conditions of speed reference.
{"title":"Energy-efficient Nonlinear Model Predictive Control of BLDC Motor in Electric Vehicles","authors":"P. Ubare, Deepak D. Ingole, D. Sonawane","doi":"10.1109/ICC47138.2019.9123204","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123204","url":null,"abstract":"The maximum distance that can be traveled at a stretch is the major limitation of today’s electric vehicle (EV). This is due to the need for maximum current, torque, and, the total onboard energy storage, etc. The distance can be increased by efficiently using the available power resources. In this paper, we present a nonlinear model predictive control (NMPC) scheme for the control of brushless direct current (BLDC) motor in EV. A control-oriented nonlinear model of the BLDC motor with EV load is considered and used in the proposed NMPC scheme. The objective of the NMPC is to control the desired torque and speed of the motor by minimizing the energy with constraints on supplied current and maximum speed. The simulation results of BLDC motor control with EV and fixed mechanical load are presented. Further, the performance of NMPC is compared with the conventional direct torque control (DTC) scheme. Presented results show that NMPC improves energy savings by 19% in fixed-load and 13% with EV load as compared to DTC under provided conditions of speed reference.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123871420","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 : 2019-12-01DOI: 10.1109/ICC47138.2019.9123156
A. D. Gomes, A. Heunis
We address a problem of unconstrained hedging within a regime-switching market model. The essence of the problem is as follows: a random variable B (called a contingent claim) is stipulated and an agent trades in a market over a fixed finite interval $tin[0, T]$. The goal of hedging is to determine the least initial wealth (called the price of the contingent claim) such that, starting from this wealth, the agent can trade in such a way that, at close of trade $t=T$, the wealth of the agent is almost-surely greater than or equal to the contingent claim B (enabling the agent to “pay off” the contingent claim). The problem of hedging (constrained as well as unconstrained) has been addressed within the framework of Brownian motion market models (see [1] and [2]). Our goal is to study this problem for market models which also include regime-switching in the sense that the market parameters are adapted not only to the filtration of a given Brownian motion (as is the case in Brownian motion market models) but to the joint filtration of a Brownian motion together with a regime-switching Markov chain.
{"title":"Unconstrained Hedging within a Regime-Switching Market Model","authors":"A. D. Gomes, A. Heunis","doi":"10.1109/ICC47138.2019.9123156","DOIUrl":"https://doi.org/10.1109/ICC47138.2019.9123156","url":null,"abstract":"We address a problem of unconstrained hedging within a regime-switching market model. The essence of the problem is as follows: a random variable B (called a contingent claim) is stipulated and an agent trades in a market over a fixed finite interval $tin[0, T]$. The goal of hedging is to determine the least initial wealth (called the price of the contingent claim) such that, starting from this wealth, the agent can trade in such a way that, at close of trade $t=T$, the wealth of the agent is almost-surely greater than or equal to the contingent claim B (enabling the agent to “pay off” the contingent claim). The problem of hedging (constrained as well as unconstrained) has been addressed within the framework of Brownian motion market models (see [1] and [2]). Our goal is to study this problem for market models which also include regime-switching in the sense that the market parameters are adapted not only to the filtration of a given Brownian motion (as is the case in Brownian motion market models) but to the joint filtration of a Brownian motion together with a regime-switching Markov chain.","PeriodicalId":231050,"journal":{"name":"2019 Sixth Indian Control Conference (ICC)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123278542","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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