Pub Date : 2021-01-01DOI: 10.26907/2541-7746.2021.3-4.276-290
V. V. Zhukov
{"title":"Synthesis of Binary Programs with Predominance of Branching Commands","authors":"V. V. Zhukov","doi":"10.26907/2541-7746.2021.3-4.276-290","DOIUrl":"https://doi.org/10.26907/2541-7746.2021.3-4.276-290","url":null,"abstract":"","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"2003 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86236327","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 : 2021-01-01DOI: 10.26907/2541-7746.2021.1.31-47
A. Aganin, T. Guseva, L. A. Kosolapova, V. Malakhov
The results of a numerical study of the axisymmetric expansion and collapse of a gas bubble and related loading on a flat rigid wall under harmonic liquid (water) pressure oscillation are presented. Initially, a spherical bubble with a radius of 1 mm and the liquid are at rest. The impulse load on the wall results from the cumulative liquid jet impact on the bubble surface part close to the wall. It was found that, for the forcing amplitude within 0.06– 0.14 MPa, the shape of the jet remains nearly the same at the forcing frequency of 0.25–4 kHz, the velocity at its impact becomes maximum at a frequency of 1.5 kHz. The forcing amplitude influence is mainly reduced to increasing the jet impact velocity. At the fixed forcing frequency and amplitude values, an increase in the initial distance between the bubble and the wall leads to an insignificant variation in the jet impact velocity. For a forcing frequency corresponding to the maximum jet velocity, some estimates of the impulse loading on the wall were determined, depending on the forcing amplitude and the initial distance between the bubble and the wall. It was found that an increase in the amplitude results in the higher and longer loading, as well as in the larger radius of the region with the maximum load.
{"title":"The Bubble Dynamics and Impulse Loading of a Rigid Surface under Acoustic Action","authors":"A. Aganin, T. Guseva, L. A. Kosolapova, V. Malakhov","doi":"10.26907/2541-7746.2021.1.31-47","DOIUrl":"https://doi.org/10.26907/2541-7746.2021.1.31-47","url":null,"abstract":"The results of a numerical study of the axisymmetric expansion and collapse of a gas bubble and related loading on a flat rigid wall under harmonic liquid (water) pressure oscillation are presented. Initially, a spherical bubble with a radius of 1 mm and the liquid are at rest. The impulse load on the wall results from the cumulative liquid jet impact on the bubble surface part close to the wall. It was found that, for the forcing amplitude within 0.06– 0.14 MPa, the shape of the jet remains nearly the same at the forcing frequency of 0.25–4 kHz, the velocity at its impact becomes maximum at a frequency of 1.5 kHz. The forcing amplitude influence is mainly reduced to increasing the jet impact velocity. At the fixed forcing frequency and amplitude values, an increase in the initial distance between the bubble and the wall leads to an insignificant variation in the jet impact velocity. For a forcing frequency corresponding to the maximum jet velocity, some estimates of the impulse loading on the wall were determined, depending on the forcing amplitude and the initial distance between the bubble and the wall. It was found that an increase in the amplitude results in the higher and longer loading, as well as in the larger radius of the region with the maximum load.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"39 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86567524","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.3.300-310
S. A. Korneev
In this paper, we examined the computational complexity of systems of monomials for some models that allow multiple use of intermediate results, such as composition circuits and multiplication circuits. For these models, we studied Shannon-type functions that characterize the maximum computational complexity of systems of monomials with exponents not exceeding the corresponding elements of a given matrix A . We found that for composition circuits, under the condition of unlimited growth of the maximum of matrix elements, this function grows asymptotically as the binary logarithm of the maximum absolute value (without regard to the sign) of the term from the determinant of the matrix A. Using generalized circuits as an auxiliary model, we transferred this result (under some restrictions) to the model of multiplication circuits.
{"title":"On the Asymptotic Behavior of Shannon-Type Functions Characterizing the Computing Complexity of Systems of Monomials","authors":"S. A. Korneev","doi":"10.26907/2541-7746.2020.3.300-310","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.3.300-310","url":null,"abstract":"In this paper, we examined the computational complexity of systems of monomials for some models that allow multiple use of intermediate results, such as composition circuits and multiplication circuits. For these models, we studied Shannon-type functions that characterize the maximum computational complexity of systems of monomials with exponents not exceeding the corresponding elements of a given matrix A . We found that for composition circuits, under the condition of unlimited growth of the maximum of matrix elements, this function grows asymptotically as the binary logarithm of the maximum absolute value (without regard to the sign) of the term from the determinant of the matrix A. Using generalized circuits as an auxiliary model, we transferred this result (under some restrictions) to the model of multiplication circuits.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"8 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78598014","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.4.441-454
A. V. Dolgopolov, D. Kazancev, I. V. Markin, O. Orlova, S. Shalaev
A complex research, which included the design, manufacture, and testing of a dynamically scaled model of the all-moving tail (AMT) of an aircraft with the numerical calculations at each stage, was carried out. The dynamically scaled model was designed to study flutter characteristics in a wind tunnel. For the all-moving tail, the model consists of a plywood core with fiberglass, carbon fiber, and shaping foam material, all glued layer by layer. In order to reliably determine the flutter boundaries, the dynamically scaled model should accurately reproduce the dynamic characteristics of the full-scale structure. With this aim, an approach was deve-loped to obtain the experimental modal characteristics and refine the dynamic mathematical models at each stage of manufacturing of the dynamically scaled model. For the dynamically scaled model refinement, one of the mathematical models was structurally similar based on finite elements, while the other one was made based on the polynomial method with plate and beam elements and then used to calculate the flutter boundaries. This approach ensured the high accuracy in modelling the dynamic properties of the full-scale all-moving tail and in the experimental determination of the flutter boundaries.
{"title":"The Modern Method of Creating Dynamically Scaled Models to Study Aircraft Flutter Characteristics","authors":"A. V. Dolgopolov, D. Kazancev, I. V. Markin, O. Orlova, S. Shalaev","doi":"10.26907/2541-7746.2020.4.441-454","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.4.441-454","url":null,"abstract":"A complex research, which included the design, manufacture, and testing of a dynamically scaled model of the all-moving tail (AMT) of an aircraft with the numerical calculations at each stage, was carried out. The dynamically scaled model was designed to study flutter characteristics in a wind tunnel. For the all-moving tail, the model consists of a plywood core with fiberglass, carbon fiber, and shaping foam material, all glued layer by layer. In order to reliably determine the flutter boundaries, the dynamically scaled model should accurately reproduce the dynamic characteristics of the full-scale structure. With this aim, an approach was deve-loped to obtain the experimental modal characteristics and refine the dynamic mathematical models at each stage of manufacturing of the dynamically scaled model. For the dynamically scaled model refinement, one of the mathematical models was structurally similar based on finite elements, while the other one was made based on the polynomial method with plate and beam elements and then used to calculate the flutter boundaries. This approach ensured the high accuracy in modelling the dynamic properties of the full-scale all-moving tail and in the experimental determination of the flutter boundaries.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"425 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80109286","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.3.367-382
K. Khadiev, D. Lin
In this paper, we considered online algorithms as a request-answer game between two players: an adversary that generates input requests and an online algorithm that answers them. A generalized version of the game that has a buffer of limited size was studied. The adversary loads data to the buffer, while the algorithm has random access to elements of the buffer. For the model, quantum and classical (deterministic or randomized) algorithms were a focus of attention. A specific problem and a quantum algorithm that works better than any classical (deterministic or randomized) algorithm, in terms of competitive ratio, were provided. At the same time, for the problem, classical online algorithms in the standard model are equivalent to the classical algorithms in the request-answer game with a buffer model.
{"title":"Quantum Online Algorithms for a Model of the Request-Answer Game with a Buffer","authors":"K. Khadiev, D. Lin","doi":"10.26907/2541-7746.2020.3.367-382","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.3.367-382","url":null,"abstract":"In this paper, we considered online algorithms as a request-answer game between two players: an adversary that generates input requests and an online algorithm that answers them. A generalized version of the game that has a buffer of limited size was studied. The adversary loads data to the buffer, while the algorithm has random access to elements of the buffer. For the model, quantum and classical (deterministic or randomized) algorithms were a focus of attention. A specific problem and a quantum algorithm that works better than any classical (deterministic or randomized) algorithm, in terms of competitive ratio, were provided. At the same time, for the problem, classical online algorithms in the standard model are equivalent to the classical algorithms in the request-answer game with a buffer model.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"85 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86428452","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.3.322-334
S. Lozhkin, V. S. Zizov
The model of cellular circuits was considered in a single basis of functional and switching elements, which is built in accordance with the standard basis B 0 consisting of Boolean functions x 1 & x 2 , x 1 ∨ x 2 , x 1 . In this model, both circuit implementing such a decoder, provided that n = 1 , 2 , . . . , is equal to n 2 n − 1 (1+ O (1 /n )). This is the first time when so-called asymptotic estimates of a high degree of accuracy, i.e., estimates with a relative error O (1 /n ), were obtained for it.
细胞电路模型是在功能和开关元件的单一基中考虑的，它是按照布尔函数x 1和x 2, x 1∨x 2, x 1组成的标准基b0建立的。在这个模型中，两个电路都实现了这样的解码器，只要n = 1,2，…。，等于n2n - 1 (1+ O (1 /n))这是第一次获得所谓的高精确度的渐近估计，即相对误差为0 (1 /n)的估计。
{"title":"Refined Estimates of the Decoder Complexity in the Model of Cellular Circuits with Functional and Switching Elements","authors":"S. Lozhkin, V. S. Zizov","doi":"10.26907/2541-7746.2020.3.322-334","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.3.322-334","url":null,"abstract":"The model of cellular circuits was considered in a single basis of functional and switching elements, which is built in accordance with the standard basis B 0 consisting of Boolean functions x 1 & x 2 , x 1 ∨ x 2 , x 1 . In this model, both circuit implementing such a decoder, provided that n = 1 , 2 , . . . , is equal to n 2 n − 1 (1+ O (1 /n )). This is the first time when so-called asymptotic estimates of a high degree of accuracy, i.e., estimates with a relative error O (1 /n ), were obtained for it.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"10 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81849855","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.3.269-284
T. Andreeva, Y. Semenov
In this paper, we explicitly calculated additional terms of cardinality asymptotics of layers in the n -dimensional k -valued lattice E nk for odd k as n → ∞. The main term had been previously determined by V.B. Alekseev for a class of posets and, particularly, for E n . Additionally, we precised the cardinality asymtotics of central layers in Cartesian powers of the non-graded poset given by V.B. Alekseev in the same work and calculated the sums of boundary functionals for the n -dimensional three-valued lattice. The obtained theorems, lemmas, and formulas are of combinatorial interest by themselves. They can also be used for estimating the cardinality of maximal antichain or the number of antichains in posets of a definite class.
{"title":"On the Cardinality of Layers in Some Partially Ordered Sets","authors":"T. Andreeva, Y. Semenov","doi":"10.26907/2541-7746.2020.3.269-284","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.3.269-284","url":null,"abstract":"In this paper, we explicitly calculated additional terms of cardinality asymptotics of layers in the n -dimensional k -valued lattice E nk for odd k as n → ∞. The main term had been previously determined by V.B. Alekseev for a class of posets and, particularly, for E n . Additionally, we precised the cardinality asymtotics of central layers in Cartesian powers of the non-graded poset given by V.B. Alekseev in the same work and calculated the sums of boundary functionals for the n -dimensional three-valued lattice. The obtained theorems, lemmas, and formulas are of combinatorial interest by themselves. They can also be used for estimating the cardinality of maximal antichain or the number of antichains in posets of a definite class.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"5 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80319898","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.4.396-410
B. Affane, A. Egorov
In this paper, we performed an asymptotic analysis for equations of the classical plate theory with the von K´arm´an strains under the assumption that the width of the plate is small compared with its length. A system of one-dimensional equations, which describes the nonlinear interaction of flexural and torsional vibrations of beams, was derived. This enab-les the possibility of exciting torsional vibrations by flexural vibrations. This possibility was analyzed for a model problem, when flexural vibrations occur in normal modes.
本文在假定板的宽度相对于板的长度较小的情况下，对经典板理论中具有von K ' arm ' an应变的方程进行了渐近分析。导出了描述梁挠曲和扭转振动非线性相互作用的一维方程组。这使得通过弯曲振动激发扭转振动成为可能。当弯曲振动在正常模式下发生时，对模型问题进行了分析。
{"title":"Asymptotic Analysis of Geometrically Nonlinear Vibrations of Long Plates","authors":"B. Affane, A. Egorov","doi":"10.26907/2541-7746.2020.4.396-410","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.4.396-410","url":null,"abstract":"In this paper, we performed an asymptotic analysis for equations of the classical plate theory with the von K´arm´an strains under the assumption that the width of the plate is small compared with its length. A system of one-dimensional equations, which describes the nonlinear interaction of flexural and torsional vibrations of beams, was derived. This enab-les the possibility of exciting torsional vibrations by flexural vibrations. This possibility was analyzed for a model problem, when flexural vibrations occur in normal modes.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"3 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76230164","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.3.311-321
V. Kochergin, A. Mikhailovich
The non-monotone complexity of realization of k -valued logic functions by circuits in a special basis was investigated. The basis consists of elements of two types: the first type comprises all monotone functions (with respect to the order 0 < 1 < 2 <···< k− 1 ) with zero weight; the second type includes non-monotone elements with unit weight, the non-empty set of which is finite. The upper and lower bounds of non-monotone complexity (the minimum number of non-monotone elements) for an arbitrary k -valued logic function were established. The difference between the upper and lower bounds does not exceed a universal constant. The difference between the best upper and lower bounds known before is a constant that depends on the basis. The range of values for these constants is infinite.
{"title":"Bounds of Non-Monotone Complexity for the Multi-Valued Logic Functions","authors":"V. Kochergin, A. Mikhailovich","doi":"10.26907/2541-7746.2020.3.311-321","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.3.311-321","url":null,"abstract":"The non-monotone complexity of realization of k -valued logic functions by circuits in a special basis was investigated. The basis consists of elements of two types: the first type comprises all monotone functions (with respect to the order 0 < 1 < 2 <···< k− 1 ) with zero weight; the second type includes non-monotone elements with unit weight, the non-empty set of which is finite. The upper and lower bounds of non-monotone complexity (the minimum number of non-monotone elements) for an arbitrary k -valued logic function were established. The difference between the upper and lower bounds does not exceed a universal constant. The difference between the best upper and lower bounds known before is a constant that depends on the basis. The range of values for these constants is infinite.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"26 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75238957","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 : 2020-01-01DOI: 10.26907/2541-7746.2020.4.467-480
V. Belashov, E. Belashova, O. Kharshiladze
The influence of the rotational regime on real long-period nutational-precessional motions of the instantaneous pole of the Earth’s rotation is considered. The solar magnetospheric (through changes in the angular velocity of rotation) mechanism of action is discussed. The observed 12-month oscillations of the instantaneous axis of rotation are explained by the influence of the deforming force arising when the angular velocity changes, which causes deformation of the figure that is not uniform in the longitudinal zones, without involving baric-circulation processes as an intermediate link. Thus, free (Chandler) and forced 12-month fluctuations of the pole position are considered from a single point of view, i.e., as resulting from the variabi-lity of the rotational regime of the Earth. The analysis of heliogeophysical data for 1900–2017 confirms the validity of the proposed relationship mechanism.
{"title":"Long-Period Nutational-Precessional Motions of the Instantaneous Earth Rotation Pole","authors":"V. Belashov, E. Belashova, O. Kharshiladze","doi":"10.26907/2541-7746.2020.4.467-480","DOIUrl":"https://doi.org/10.26907/2541-7746.2020.4.467-480","url":null,"abstract":"The influence of the rotational regime on real long-period nutational-precessional motions of the instantaneous pole of the Earth’s rotation is considered. The solar magnetospheric (through changes in the angular velocity of rotation) mechanism of action is discussed. The observed 12-month oscillations of the instantaneous axis of rotation are explained by the influence of the deforming force arising when the angular velocity changes, which causes deformation of the figure that is not uniform in the longitudinal zones, without involving baric-circulation processes as an intermediate link. Thus, free (Chandler) and forced 12-month fluctuations of the pole position are considered from a single point of view, i.e., as resulting from the variabi-lity of the rotational regime of the Earth. The analysis of heliogeophysical data for 1900–2017 confirms the validity of the proposed relationship mechanism.","PeriodicalId":41863,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta-Seriya Fiziko-Matematicheskie Nauki","volume":"27 supp1 1","pages":""},"PeriodicalIF":0.3,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89851333","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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