Journal of Sound and Vibration最新文献_第9页

A novel flexible infinite element for transient acoustic simulations 一种用于瞬态声学模拟的新型柔性无限元

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-26 DOI: 10.1016/j.jsv.2024.118854

D. Bizzarri , S. van Ophem , P. Marchner , O. Atak , H. Bériot

{"title":"A novel flexible infinite element for transient acoustic simulations","authors":"D. Bizzarri , S. van Ophem , P. Marchner , O. Atak , H. Bériot","doi":"10.1016/j.jsv.2024.118854","DOIUrl":"10.1016/j.jsv.2024.118854","url":null,"abstract":"<div><div>This article addresses the efficient solution of exterior acoustic transient problems using the Finite Element Method (FEM) in combination with infinite elements. Infinite elements are a popular technique to enforce non-reflecting boundary conditions. The Astley–Leis formulation presents several advantages in terms of ease of implementation, and results in frequency-independent system matrices, that can be used for transient simulations of wave propagation phenomena. However, for time-domain simulations, the geometrical flexibility of Astley–Leis infinite elements is limited by time-stability requirements. In this article, we present a novel infinite element formulation, called flexible infinite element, for which the accuracy does not depend on the positioning of the virtual sources. From a software implementation perspective, the element proposed can be seen as a specialized FEM element and can be easily integrated into a high-order FEM code. The effectiveness of the flexible formulation is demonstrated with frequency and time-domain examples; for both cases, we show how the flexible infinite elements can be attached to arbitrarily-shaped convex FE boundaries. In particular, we show how the proposed technique can be used in combination with existing model order reduction strategies to run fast and accurate transient simulations.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118854"},"PeriodicalIF":4.3,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimizing design of openings in vibrating plates for enhanced vibro-acoustic performance using a genetic algorithm approach 利用遗传算法优化振动板开口设计，提高振动声学性能

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-25 DOI: 10.1016/j.jsv.2024.118847

Khaled Said Ahmed Maamoun , Stanislaw Wrona , Marek Pawelczyk , Hamid Reza Karimi

{"title":"Optimizing design of openings in vibrating plates for enhanced vibro-acoustic performance using a genetic algorithm approach","authors":"Khaled Said Ahmed Maamoun , Stanislaw Wrona , Marek Pawelczyk , Hamid Reza Karimi","doi":"10.1016/j.jsv.2024.118847","DOIUrl":"10.1016/j.jsv.2024.118847","url":null,"abstract":"<div><div>Optimizing structural openings in vibro-acoustic systems is essential for balancing functional needs with acoustic performance in various engineering applications. This paper presents an efficient optimization approach for designing openings in plate structures within vibro-acoustic systems, aimed at enhancing acoustic performance while maintaining structural integrity. A genetic algorithm framework is developed to determine the optimal shapes and locations of openings simultaneously, utilizing an analytical model based on hyperbolic and trigonometric admissible functions within a master–slave software architecture. The proposed method accommodates a variety of opening requirements for different systems and employs a cost function that evaluates both the average and peaks of sound power responses to identify the designs with the highest fitness. This results in significant reductions in sound power levels compared to median and worst-case designs. Additionally, the method analyzes how variations in opening locations, numbers, and shapes impact acoustic performance, providing guidance for opening designs that avoid undesired acoustic outcomes and improve noise barrier performance in vibro-acoustic systems.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"598 ","pages":"Article 118847"},"PeriodicalIF":4.3,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142719922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Axisymmetric forced vibration of the hydro-elastic system consisting of a pre-strained highly elastic plate and compressible viscous fluid 由预应变高弹性板和可压缩粘性流体组成的水弹性系统的轴对称强迫振动

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-24 DOI: 10.1016/j.jsv.2024.118862

Surkay D. Akbarov , Jamila N. Imamaliyeva

{"title":"Axisymmetric forced vibration of the hydro-elastic system consisting of a pre-strained highly elastic plate and compressible viscous fluid","authors":"Surkay D. Akbarov , Jamila N. Imamaliyeva","doi":"10.1016/j.jsv.2024.118862","DOIUrl":"10.1016/j.jsv.2024.118862","url":null,"abstract":"<div><div>The paper studies the axisymmetric harmonic forced vibration of the hydro-elastic system composed of an initially strained plate made of highly elastic material, a compressible viscous fluid layer, and a rigid wall restricting the fluid flow. It is assumed that the plate is in contact with the fluid layer after the appearance of the finite axisymmetric homogeneous initial strains within which are caused by the stretching of the plate by uniformly distributed radial forces acting at infinity. Also, it is assumed that after this contact, the point located time-harmonic force begins to act on the free-face plane of the plate. Within this framework, the steady-state forced vibration of the hydro-elastic system under consideration is studied by employing the eq. and relations of the so-called three-dimensional linearized theory of elastic waves in bodies with finite initial strains to describe the motion of the plate and by employing the linearized Navier-Stokes eq. to describe the flow of the fluid. The corresponding mathematical problem is solved by employing the Hankel integral transform method, and the originals of the sought values are found numerically by employing the algorithms and PC programs composed by the authors. Numerical results are presented and discussed on the frequency response of the normal stress acting on the interface plane between the plate and fluid layer. According to these discussions, corresponding conclusions on the influence of the problem parameters on the frequency response of the interface stress are made. In particular, it is established that in the axisymmetric forced vibration case, the resonance-type phenomenon appears due to the fluid viscosity.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"598 ","pages":"Article 118862"},"PeriodicalIF":4.3,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Acoustic enhancement and weak signal detection based on quasibound states in the continuum 基于连续介质中准束缚态的声增强和弱信号检测

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-23 DOI: 10.1016/j.jsv.2024.118856

Junrui Jiao, Chengyong Wang, Dejie Yu

{"title":"Acoustic enhancement and weak signal detection based on quasibound states in the continuum","authors":"Junrui Jiao, Chengyong Wang, Dejie Yu","doi":"10.1016/j.jsv.2024.118856","DOIUrl":"10.1016/j.jsv.2024.118856","url":null,"abstract":"<div><div>Acoustic signal detection is important in several fields of research. However, realizing weak-signal detection remains a challenge. Recently, the bound state in continuum (BIC) has attracted considerable attention because of its ultrahigh quality-factor (<em>Q</em>-factor) and strong field enhancement. In this study, we achieved two Fabry–Perot BICs (bonding and anti-bonding BICs) in a coupled-resonator system and a mirror-induced BIC in a single-resonator system. And the acoustic enhancement from quasi-BICs of the coupled-resonator system and single-resonator system was investigated in the simulation. Compared to the coupled-resonator system, the amplification performance of the single-resonator system was better and verified in the experiment. The experimental results agreed with the numerical results, and the maximum pressure magnification was approximately 28×. Furthermore, the single-resonator system enhanced the weak harmonic signal, weak periodic impulse signal, and weak modulated signal in the presence of strong background noise, making signal detection much easier. We believe that this work provides a new method to realize weak signal detection based on acoustic enhancement.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"598 ","pages":"Article 118856"},"PeriodicalIF":4.3,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pole-zero placement through the robust receptance method for multi-input active vibration control with time delay 基于鲁棒接受法的极点零配置多输入时滞主动振动控制

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-22 DOI: 10.1016/j.jsv.2024.118850

José Mário Araújo , Nelson J.B. Dantas , Carlos E.T. Dórea , Dario Richiedei , Iacopo Tamellin

{"title":"Pole-zero placement through the robust receptance method for multi-input active vibration control with time delay","authors":"José Mário Araújo , Nelson J.B. Dantas , Carlos E.T. Dórea , Dario Richiedei , Iacopo Tamellin","doi":"10.1016/j.jsv.2024.118850","DOIUrl":"10.1016/j.jsv.2024.118850","url":null,"abstract":"<div><div>Vibration control is fundamental to improve the performances of lightweight flexible systems. However, the introduction of sensors and actuators in the control loop introduces time-delays which must be carefully considered during the tuning stage to obtain effective controllers. This paper proposes a novel approach for the design of state and state-derivative feedback active vibration controllers in multi-input systems with time delay. The method exploits the versatility provided by the system receptances: two procedures are presented to compute the control gain matrices that simultaneously assign the antiresonance frequencies (zero assignment) and a subset of the desired closed-loop poles (partial pole placement). The notion of <em>eigenloci</em> of the loop gain, an extension of the Nyquist plot for multi-input systems, is used to impose closed-loop stability and guaranteed robustness margins to the closed-loop system. A Genetic Algorithm is exploited to search a solution of the control non-convex optimization problem. The effectiveness of the proposed method is assessed through numerical simulations on some benchmark systems taken from the literature. The obtained results highlight that besides assigning the prescribed zeros and poles, the proposed method enables to obtain stable closed-loop systems with guaranteed phase and gain margins.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118850"},"PeriodicalIF":4.3,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultrasonic modeling for multi-layered fluid-solid coupling structures considering defective interfaces: An efficient semi-analytical spectral element method

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-22 DOI: 10.1016/j.jsv.2024.118861

Jiaqi Xu , Hengshan Hu , Qing Huo Liu , Bo Han

{"title":"Ultrasonic modeling for multi-layered fluid-solid coupling structures considering defective interfaces: An efficient semi-analytical spectral element method","authors":"Jiaqi Xu , Hengshan Hu , Qing Huo Liu , Bo Han","doi":"10.1016/j.jsv.2024.118861","DOIUrl":"10.1016/j.jsv.2024.118861","url":null,"abstract":"<div><div>Ultrasonic guided waves play a crucial role in the long-distance inspection of the fluid-solid coupling structures with defective interfaces. However, it is a challenge to calculate dispersion curves for a large number of wave modes due to the complexity of the waveguide structure. In this study, we propose an efficient semi-analytical spectral element method considering a variant-stiffness linear-slip condition to model fluid-solid coupling systems with damaged interfaces. The computational accuracy and efficiency of the proposed method are validated by comparing it with the reference solutions across various numerical scenarios, including immersed solid layers, immersed solid layers with multiple defective interfaces, and fluid-solid coupling structures with thin leaky fluid layers. Additionally, we investigate how the defects influence the dispersion characteristics of trapped or leaky wave modes, illustrating that the advantage of the high-order wave for the long-distance detection of damaged zones. The proposed method can serve as an efficient and robust numerical tool for modeling and characterizing ultrasonic non-detective testing of the damaged fluid-solid coupling structures.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118861"},"PeriodicalIF":4.3,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143152689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design of six-parameter isolator using internal mass effect for improving vibration isolation 利用内质量效应设计提高隔振性能的六参数隔振器

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-22 DOI: 10.1016/j.jsv.2024.118859

Jing Li , Weipeng Li , Weidong Yu , Qingqing Xu , Hai Huang

{"title":"Design of six-parameter isolator using internal mass effect for improving vibration isolation","authors":"Jing Li , Weipeng Li , Weidong Yu , Qingqing Xu , Hai Huang","doi":"10.1016/j.jsv.2024.118859","DOIUrl":"10.1016/j.jsv.2024.118859","url":null,"abstract":"<div><div>Isolators designed based on a three-parameter model (or its equivalent five-parameter model) are used for vibration isolation of sensitive payloads. The three-parameter model consists of a spring arranged in parallel with an elastically supported damper. The three-parameter isolator performs better than conventional isolators, which are primarily based on a parallel spring–damper structure. However, it tends to sacrifice the resonance suppression at low frequencies when enhancing damping at high frequencies. Previous studies have shown that the internal moving mass of a three-parameter isolator, which had been neglected, can be beneficial for improving high-frequency vibration isolation; however, few design methods have been presented. Hence, we propose a six-parameter model based on the five-parameter model by considering the internal mass. This model combines the advantages of the internal mass effect and offers more designable parameters than the three-parameter model. In this study, the optimum damping of a six-parameter model was determined. An optimization method for the six-parameter model was proposed to maximize high-frequency isolation. Subsequently, an optimal six-parameter isolator was designed and tested. The results showed that the optimal six-parameter isolator can provide greater isolation by 30 dB than the three-parameter isolator at frequencies above 200 Hz, thereby validating the design method. This study provides new ideas for utilizing internal mass to improve vibration isolation.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118859"},"PeriodicalIF":4.3,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic characterization of permanent magnet electrodynamic suspension system with a novel passive damping magnet scheme 采用新型被动阻尼磁体方案的永磁电动悬架系统动态特性研究

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-22 DOI: 10.1016/j.jsv.2024.118849

Chuan Wu , Guanchun Li , Dong Wang , Jie Xu

{"title":"Dynamic characterization of permanent magnet electrodynamic suspension system with a novel passive damping magnet scheme","authors":"Chuan Wu , Guanchun Li , Dong Wang , Jie Xu","doi":"10.1016/j.jsv.2024.118849","DOIUrl":"10.1016/j.jsv.2024.118849","url":null,"abstract":"<div><div>In the paper, a 3D electromagnetic force analytical model incorporating the vertical vibration velocity of the permanent magnet is derived using the virtual magnetic charge method, which is used to examine the system’s dynamic properties. Then, a novel passive damping scheme based on permanent magnets is developed to enhance the system stability without increasing the complexity of the system. Finally, the dynamic experiment is carried out on the rotating platform employing a dynamic test apparatus, where the validity of the analytical model is checked and the effect of the damping magnet is explored. The results exhibit that the permanent magnet electrodynamic suspension system is self-stabilizing yet underdamped, and the vertical damping coefficient decreases as the velocity and airgap increase. The system has favorable stability in the absence of disturbance with a fluctuation of roughly 0.5 mm. The proposed damping scheme reduces the vibration overshoot from 41.18% to 32.47% and shortens the settling time from 3.29 s to 0.97 s. Meanwhile, the system is especially sensitive to long-wave irregularities in the high-speed range throughout the experiment with the track irregularity, where the vibration amplitude of the guidance system can be reduced by approximately 8 times from 4.6 mm to 0.57 mm by applying the damping magnet scheme. As a result, the proposed passive damping magnet scheme offers a pretty damping effect, which is capable of significantly improving the stability of the permanent magnet electrodynamic suspension system.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"599 ","pages":"Article 118849"},"PeriodicalIF":4.3,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A spectral element-based reduced order model for thermoacoustic stability analysis in waveguides 基于谱元的波导热声稳定性分析降阶模型

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-20 DOI: 10.1016/j.jsv.2024.118834

Dario Passato , Danilo Beli , Ines Lopez Arteaga

{"title":"A spectral element-based reduced order model for thermoacoustic stability analysis in waveguides","authors":"Dario Passato , Danilo Beli , Ines Lopez Arteaga","doi":"10.1016/j.jsv.2024.118834","DOIUrl":"10.1016/j.jsv.2024.118834","url":null,"abstract":"<div><div>A novel approach to perform linear stability analysis using a spectral element-based reduced order model is proposed, thereby facilitating the comprehensive study of (thermo)acoustic (in)stability across complex waveguide configurations. Providing a generalization of a wave-based method (e.g. spectral element method) to the Laplace domain, this study is offering not only a new methodology for analyzing thermoacoustic systems but also expanding the application of the spectral element method and other wave-based techniques to a broader class of problems. By solving the wave equation in the Laplace domain, spectral elementary matrices can be defined in the complex plane in both wavenumber and frequency domains, allowing for an examination of system stability. This technique supports a wide range of waveguide investigations, whether using an analytical description to get the spectral matrix or a numerical method to determine the dispersion curves and eigenvectors in the cross-section. Additionally, the proposed method simplifies the implementation of parametric optimization procedures due to its low computational cost, thus offering significant advancements in the study of waveguide behavior of thermoacoustic systems.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"598 ","pages":"Article 118834"},"PeriodicalIF":4.3,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analytical solutions for free vibrations of rectangular cuboid elastic lattices and their continuous approximations

IF 4.3 2区工程技术

Journal of Sound and Vibration Pub Date : 2024-11-19 DOI: 10.1016/j.jsv.2024.118836

H.P. Nguyen , Noël Challamel , C.M. Wang

{"title":"Analytical solutions for free vibrations of rectangular cuboid elastic lattices and their continuous approximations","authors":"H.P. Nguyen , Noël Challamel , C.M. Wang","doi":"10.1016/j.jsv.2024.118836","DOIUrl":"10.1016/j.jsv.2024.118836","url":null,"abstract":"<div><div>This paper presents analytical solutions for the free vibration of an elastic cuboid lattice (rectangular parallelepiped) with sliding supports along its planar boundaries. The lattice model includes both central and angular interactions. The free vibration problem is solved by formulating a 3D difference eigenvalue problem, and exact solutions for the eigenfrequencies and eigenmodes are derived analytically using a trigonometric discrete displacement field. A cubic equation for the eigenfrequency squares is obtained, with solutions determined using Cardano's formula. The derived exact solutions for the finite cuboid lattice are validated by comparison with solutions obtained from a discrete algebraic method, calibrated for accurate stiffness and mass properties both within the lattice and at its boundaries. Furthermore, these exact solutions for the 3D lattice are benchmarked against analytical solutions for the corresponding 3D continuum, based on classical elasticity, lattice-based gradient elasticity, and lattice-based nonlocal elasticity theories, demonstrating their accuracy and reliability for free vibration analysis.</div></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":"600 ","pages":"Article 118836"},"PeriodicalIF":4.3,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0