Pub Date : 2024-11-05DOI: 10.1134/S0005117924700073
I. P. Karpova, V. E. Karpov
This paper explores the problem of influencing the environment by a group of autonomous robots through the creation and use of road infrastructure. The model object is ant roads (trails). We identify the main aspects of the behavior of different ant species in the process of collective foraging, and actions that together lead to the appearance of a phenomenon that the observer perceives as an ant road. We develop and describe an animat behavior model in the process of arranging a route. We define a list of mechanisms, a set of sensory capabilities, and effectors that are necessary for the robot to implement options for arranging the route. The results of simulation modeling for solving the foraging problem with route clearing are consistent with theoretical models. The simulation results confirm our assumption that the route arrangement can be carried out by individual efforts of animats (robots) and without the need to organize joint actions.
{"title":"“Pitfalls” of Bio-Inspired Models on the Example of Ant Trails","authors":"I. P. Karpova, V. E. Karpov","doi":"10.1134/S0005117924700073","DOIUrl":"10.1134/S0005117924700073","url":null,"abstract":"<p>This paper explores the problem of influencing the environment by a group of autonomous robots through the creation and use of road infrastructure. The model object is ant roads (trails). We identify the main aspects of the behavior of different ant species in the process of collective foraging, and actions that together lead to the appearance of a phenomenon that the observer perceives as an ant road. We develop and describe an animat behavior model in the process of arranging a route. We define a list of mechanisms, a set of sensory capabilities, and effectors that are necessary for the robot to implement options for arranging the route. The results of simulation modeling for solving the foraging problem with route clearing are consistent with theoretical models. The simulation results confirm our assumption that the route arrangement can be carried out by individual efforts of animats (robots) and without the need to organize joint actions.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 7","pages":"641 - 651"},"PeriodicalIF":0.6,"publicationDate":"2024-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142579372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060055
V. N. Chestnov, D. V. Shatov
This paper considers linear multivariable systems with physical parameters varying from their known nominal values in an arbitrary and nonstationary manner. The plant is subjected to polyharmonic external disturbances containing an arbitrary number of unknown frequencies with unknown amplitudes having a bounded sum. The problem is to design a controller that robustly stabilizes the closed loop system and ensures desired errors for the controlled variables of the plant with nominal parameters in the steady-state mode. The system equations of the original problem are represented in the (W, Λ, K)-form; for this form, the standard H∞ optimization problem is stated and solved. The desired accuracy of the system is achieved by analytically assigning the weight matrix of the controlled variables. The controller design method is illustrated by an example of solving a well-known benchmark problem.
{"title":"Robust Controller Design for Multivariable Systems under Nonstationary Parametric Variations and Bounded External Disturbances","authors":"V. N. Chestnov, D. V. Shatov","doi":"10.1134/S0005117924060055","DOIUrl":"10.1134/S0005117924060055","url":null,"abstract":"<p>This paper considers linear multivariable systems with physical parameters varying from their known nominal values in an arbitrary and nonstationary manner. The plant is subjected to polyharmonic external disturbances containing an arbitrary number of unknown frequencies with unknown amplitudes having a bounded sum. The problem is to design a controller that robustly stabilizes the closed loop system and ensures desired errors for the controlled variables of the plant with nominal parameters in the steady-state mode. The system equations of the original problem are represented in the (<i>W</i>, Λ, <i>K</i>)-form; for this form, the standard <i>H</i><sub>∞</sub> optimization problem is stated and solved. The desired accuracy of the system is achieved by analytically assigning the weight matrix of the controlled variables. The controller design method is illustrated by an example of solving a well-known benchmark problem.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"489 - 501"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060080
D. V. Shatov
The considered problem is to simultaneously stabilize a family of second order linear systems by static linear state feedback when applied to switched systems. The proposed synthesis approach is based on a known design method where a static regulator is found as a solution to the linear programming problem. This regulator makes all matrices from the family forming switched systems superstable in the closed loop state, which in turn guarantees exponential stability of the switched system. This approach is generalized for the case where not all matrices in the family can simultaneously be made superstable: for non-superstabilizable matrices one determines using D-decomposition linear bounds on the set of stabilizing regulators, which are used in the linear programming problem. The designed switched system properties are briefly studied. An example of a design problem solution using the proposed approach is presented.
所考虑的问题是,当应用于开关系统时,如何通过静态线性状态反馈同时稳定二阶线性系统族。所提出的合成方法基于一种已知的设计方法,即找到一个静态调节器作为线性规划问题的解决方案。该调节器可使构成开关系统的所有矩阵在闭环状态下保持超稳定,进而保证开关系统的指数稳定性。这种方法也适用于并非所有矩阵都能同时超稳定的情况:对于不可超稳定的矩阵,可以使用 D 分解法确定稳定调节器集合的线性边界,并将其用于线性规划问题。对所设计的开关系统特性进行了简要研究。此外,还介绍了一个使用所提方法解决设计问题的实例。
{"title":"Simultaneous Stabilization of Second Order Linear Switched Systems Based on Superstability and D-Decomposition Technique","authors":"D. V. Shatov","doi":"10.1134/S0005117924060080","DOIUrl":"10.1134/S0005117924060080","url":null,"abstract":"<p>The considered problem is to simultaneously stabilize a family of second order linear systems by static linear state feedback when applied to switched systems. The proposed synthesis approach is based on a known design method where a static regulator is found as a solution to the linear programming problem. This regulator makes all matrices from the family forming switched systems superstable in the closed loop state, which in turn guarantees exponential stability of the switched system. This approach is generalized for the case where not all matrices in the family can simultaneously be made superstable: for non-superstabilizable matrices one determines using <i>D</i>-decomposition linear bounds on the set of stabilizing regulators, which are used in the linear programming problem. The designed switched system properties are briefly studied. An example of a design problem solution using the proposed approach is presented.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"502 - 511"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060067
M. V. Khlebnikov
This paper considers filtering for linear systems subjected to persistent exogenous disturbances. The filtering quality is characterized by the size of the bounding ellipsoid that contains the estimated output of the system. A regular approach is proposed to solve the nonfragile filtering problem. This problem consists in designing a filter matrix that withstands admissible variations of its coefficients. The concept of invariant ellipsoids is applied to reformulate the original problem in terms of linear matrix inequalities and reduce it to a parametric semidefinite programming problem easily solved numerically. This paper continues the series of author’s research works devoted to filtering under nonrandom bounded exogenous disturbances and measurement errors.
{"title":"Nonfragile Filtering under Bounded Exogenous Disturbances","authors":"M. V. Khlebnikov","doi":"10.1134/S0005117924060067","DOIUrl":"10.1134/S0005117924060067","url":null,"abstract":"<p>This paper considers filtering for linear systems subjected to persistent exogenous disturbances. The filtering quality is characterized by the size of the bounding ellipsoid that contains the estimated output of the system. A regular approach is proposed to solve the nonfragile filtering problem. This problem consists in designing a filter matrix that withstands admissible variations of its coefficients. The concept of invariant ellipsoids is applied to reformulate the original problem in terms of linear matrix inequalities and reduce it to a parametric semidefinite programming problem easily solved numerically. This paper continues the series of author’s research works devoted to filtering under nonrandom bounded exogenous disturbances and measurement errors.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"477 - 488"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060079
M. M. Kogan, A. V. Stepanov
This paper demonstrates that robust control based on only a priori information about the object’s uncertainty can be significantly improved through the additional use of experimental data. Generalized H∞-optimal controllers are designed for an unknown linear time-varying system on a finite horizon. These controllers optimize the damping level of exogenous and/or initial disturbances as well as the maximum deviation of the terminal state of the system. The design method does not require the persistent excitation condition or the rank condition, which ensure the identifiability of the system. As a result, the amount of experimental data can be significantly reduced.
{"title":"How to Improve Robust Control of a Linear Time-Varying System by Using Experimental Data","authors":"M. M. Kogan, A. V. Stepanov","doi":"10.1134/S0005117924060079","DOIUrl":"10.1134/S0005117924060079","url":null,"abstract":"<p>This paper demonstrates that robust control based on only a priori information about the object’s uncertainty can be significantly improved through the additional use of experimental data. Generalized <i>H</i><sub>∞</sub>-optimal controllers are designed for an unknown linear time-varying system on a finite horizon. These controllers optimize the damping level of exogenous and/or initial disturbances as well as the maximum deviation of the terminal state of the system. The design method does not require the persistent excitation condition or the rank condition, which ensure the identifiability of the system. As a result, the amount of experimental data can be significantly reduced.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"557 - 574"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060031
P. A. Arkhipov
This paper is dedicated to an optimization problem. Let A, B ⊂ ({{mathbb{R}}^{n}}) be compact convex sets. Consider the minimal number t0 > 0 such that t0B covers A after a shift to a vector x0 ∈ ({{mathbb{R}}^{n}}). The goal is to find t0 and x0. In the special case of B being a unit ball centered at zero, x0 and t0 are known as the Chebyshev center and the Chebyshev radius of A. This paper focuses on the case in which A and B are defined with their black-box support functions. An algorithm for solving such problems efficiently is suggested. The algorithm has a superlinear convergence rate, and it can solve hundred-dimensional test problems in a reasonable time, but some additional conditions on A and B are required to guarantee the presence of convergence. Additionally, the behavior of the algorithm for a simple special case is investigated, which leads to a number of theoretical results. Perturbations of this special case are also studied.
本文专门讨论一个优化问题。设 A, B ⊂ ({{mathbb{R}}^{n}})是紧凑凸集。考虑最小数 t0 > 0,使得 t0B 在移动到向量 x0∈ ({{mathbb{R}}^{n}})后覆盖 A。我们的目标是找到 t0 和 x0。在 B 是以零为中心的单位球的特殊情况下,x0 和 t0 被称为 A 的切比雪夫中心和切比雪夫半径。本文提出了一种高效解决此类问题的算法。该算法具有超线性收敛速度,可以在合理的时间内解决百维测试问题,但需要对 A 和 B 附加一些条件以保证收敛性的存在。此外,我们还研究了该算法在一个简单特例中的行为,并由此得出了一些理论结果。还研究了这种特殊情况的扰动。
{"title":"An Algorithm for Finding the Generalized Chebyshev Center of Sets Defined via Their Support Functions","authors":"P. A. Arkhipov","doi":"10.1134/S0005117924060031","DOIUrl":"10.1134/S0005117924060031","url":null,"abstract":"<p>This paper is dedicated to an optimization problem. Let <i>A</i>, <i>B</i> ⊂ <span>({{mathbb{R}}^{n}})</span> be compact convex sets. Consider the minimal number <i>t</i><sup>0</sup> > 0 such that <i>t</i><sup>0</sup><i>B</i> covers <i>A</i> after a shift to a vector <i>x</i><sup>0</sup> ∈ <span>({{mathbb{R}}^{n}})</span>. The goal is to find <i>t</i><sup>0</sup> and <i>x</i><sup>0</sup>. In the special case of <i>B</i> being a unit ball centered at zero, <i>x</i><sup>0</sup> and <i>t</i><sup>0</sup> are known as the Chebyshev center and the Chebyshev radius of <i>A</i>. This paper focuses on the case in which <i>A</i> and <i>B</i> are defined with their black-box support functions. An algorithm for solving such problems efficiently is suggested. The algorithm has a superlinear convergence rate, and it can solve hundred-dimensional test problems in a reasonable time, but some additional conditions on <i>A</i> and <i>B</i> are required to guarantee the presence of convergence. Additionally, the behavior of the algorithm for a simple special case is investigated, which leads to a number of theoretical results. Perturbations of this special case are also studied.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"522 - 532"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060043
L. M. Berlin, A. A. Galyaev, P. V. Lysenko
The time-optimal control problem for an arbitrary number of nonsynchronous oscillators with a limited scalar control is considered. An analytical investigation of the problem is performed. The property of strong accessibility and global controllability is proved, and a program control is found that brings the system from the origin to a fixed point in the shortest time. Trajectories satisfying both the motion equations of the system and the additional conditions based on the matrix nondegeneracy conditions of the relay control have been found for bringing a group of oscillators to the origin. Two classification methods of trajectories according to the number of control switchings are compared: the one based on the necessary extremum conditions and the Neustadt–Eaton numerical algorithm.
{"title":"Necessary Extremum Conditions and the Neustadt–Eaton Method in the Time-Optimal Control Problem for a Group of Nonsynchronous Oscillators","authors":"L. M. Berlin, A. A. Galyaev, P. V. Lysenko","doi":"10.1134/S0005117924060043","DOIUrl":"10.1134/S0005117924060043","url":null,"abstract":"<p>The time-optimal control problem for an arbitrary number of nonsynchronous oscillators with a limited scalar control is considered. An analytical investigation of the problem is performed. The property of strong accessibility and global controllability is proved, and a program control is found that brings the system from the origin to a fixed point in the shortest time. Trajectories satisfying both the motion equations of the system and the additional conditions based on the matrix nondegeneracy conditions of the relay control have been found for bringing a group of oscillators to the origin. Two classification methods of trajectories according to the number of control switchings are compared: the one based on the necessary extremum conditions and the Neustadt–Eaton numerical algorithm.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"543 - 556"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S000511792406002X
R. P. Agaev, D. K. Khomutov
Coordination in multiagent systems with information influences is studied. In particular, a model of multiagent system in which information is transmitted with a constant delay for all agents is studied. Using the Nyquist criterion applied by Tsypkin for systems with delayed feedback, a formula is obtained for the boundary value of time-delay which is included as a parameter in the system of differential equations with an asymmetric constant Laplacian matrix. The condition of independence of stability from time-delay is founded. The results obtained generalize some previously results and can be applied in coordination analysis in a multiagent systems with complex protocol.
{"title":"On the Boundary Value of the Time-Delay and the Asymptotic Behavior of a Continuous First-Order Consensus Protocol","authors":"R. P. Agaev, D. K. Khomutov","doi":"10.1134/S000511792406002X","DOIUrl":"10.1134/S000511792406002X","url":null,"abstract":"<p>Coordination in multiagent systems with information influences is studied. In particular, a model of multiagent system in which information is transmitted with a constant delay for all agents is studied. Using the Nyquist criterion applied by Tsypkin for systems with delayed feedback, a formula is obtained for the boundary value of time-delay which is included as a parameter in the system of differential equations with an asymmetric constant Laplacian matrix. The condition of independence of stability from time-delay is founded. The results obtained generalize some previously results and can be applied in coordination analysis in a multiagent systems with complex protocol.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"533 - 542"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1134/S0005117924060092
P. S. Shcherbakov
We consider a class of well-known high-order trinomial linear difference equations and analyze the non-asymptotic behavior of their solutions under non-zero initial conditions from the unit box. It is shown that, for certain subsets of coefficients in the stability domain, there always exist initial conditions leading to peak, a large deviation of solutions from the equilibrium position, and that these deviations may take arbitrarily large values. Various special cases are studied, numerical examples are presented.
{"title":"Analysis of Peak Effects in the Solutions of a Class of Difference Equations","authors":"P. S. Shcherbakov","doi":"10.1134/S0005117924060092","DOIUrl":"10.1134/S0005117924060092","url":null,"abstract":"<p>We consider a class of well-known high-order trinomial linear difference equations and analyze the non-asymptotic behavior of their solutions under non-zero initial conditions from the unit box. It is shown that, for certain subsets of coefficients in the stability domain, there always exist initial conditions leading to peak, a large deviation of solutions from the equilibrium position, and that these deviations may take arbitrarily large values. Various special cases are studied, numerical examples are presented.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 6","pages":"512 - 521"},"PeriodicalIF":0.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142443315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-06DOI: 10.1134/S0005117924050059
E. N. Gryazina, D. Y. Baluev
The paper is devoted to the analysis of the feasibility domain of electric power systems. The problems of calculating feasible and marginal regimes of power systems, analyzing the geometry of the feasibility domain, and generating samples in this region are considered. Parallels are drawn with the works of B.T. Polyak on the analysis of the image of a quadratic map, modification of the Newton method and the development of methods for generating asymptotically uniform samples in areas with complex geometry. Particular attention is paid to Newton’s method with the transversality condition (TENR), its application for constructing a boundary oracle procedure and utilization for generating samples in the power system feasibility domain.
摘要 本文致力于分析电力系统的可行性域。文中考虑了计算电力系统的可行和边际制度、分析可行性域的几何形状以及在该区域生成样本等问题。该书与 B.T. Polyak 在二次图象分析、牛顿方法的修改以及在具有复杂几何形状的区域生成渐近均匀样本的方法开发等方面的著作有相似之处。特别关注的是牛顿方法与横向条件(TENR)、其在构建边界甲骨文程序中的应用以及在电力系统可行性领域中生成样本的利用。
{"title":"Investigation of Feasible and Marginal Operating Regimes of Electric Power Systems","authors":"E. N. Gryazina, D. Y. Baluev","doi":"10.1134/S0005117924050059","DOIUrl":"10.1134/S0005117924050059","url":null,"abstract":"<p>The paper is devoted to the analysis of the feasibility domain of electric power systems. The problems of calculating feasible and marginal regimes of power systems, analyzing the geometry of the feasibility domain, and generating samples in this region are considered. Parallels are drawn with the works of B.T. Polyak on the analysis of the image of a quadratic map, modification of the Newton method and the development of methods for generating asymptotically uniform samples in areas with complex geometry. Particular attention is paid to Newton’s method with the transversality condition (TENR), its application for constructing a boundary oracle procedure and utilization for generating samples in the power system feasibility domain.</p>","PeriodicalId":55411,"journal":{"name":"Automation and Remote Control","volume":"85 5","pages":""},"PeriodicalIF":0.6,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142198064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}