International Journal of Mechanical Sciences最新文献

{"title":"Isogeometric shape optimization method for vibration of variable section blade","authors":"Saifeng Zhong ,&nbsp;Guoyong Jin ,&nbsp;Shanjun Li ,&nbsp;Qingtao Gong ,&nbsp;Na Wang","doi":"10.1016/j.ijmecsci.2025.110129","DOIUrl":"10.1016/j.ijmecsci.2025.110129","url":null,"abstract":"<div><div>An accurate and efficient shape optimization model is a practical approach to improving the vibration characteristics of blades. This paper proposes an isogeometric shape optimization method that uses control point coordinates as optimal design variables for the rotating variable-section blade model. The local modification feature of NURBS curves allows for the adjustment of blade profiles without the need to change the number and quality of parameter elements. Integrating the centrifugal force step-by-step solution method and three-dimensional elasticity theory, while accounting for centrifugal shear stress and omitting deformation assumptions, a vibration solving model of the rotating variable section blades is firstly established to determine the objective function for blade optimization. By comparing with the numerical data from the finite element method (FEM) and modal experiments, the accuracy and effectiveness of the current vibration modelling method are validated. Using the Campbell diagram, a safe operational range is determined to avoid resonance at certain rotational speeds. This constraint is then applied to find the optimal lightweight shape for the blade. Finally, the effects of different rotational speeds, constraints, and design variable variation ranges on the shape optimization results are investigated. The method can perform extensive analysis automatically by changing the geometric design parameters, which greatly improves the efficiency of blade optimization design and provides a new idea for blade optimization design.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110129"},"PeriodicalIF":7.1,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating the dynamic behavior of marine gear transmission system considering ship rolling motion","authors":"Yiwei Hu ,&nbsp;Zheming Tong ,&nbsp;Shuiguang Tong ,&nbsp;Xianmiao Yang","doi":"10.1016/j.ijmecsci.2025.110126","DOIUrl":"10.1016/j.ijmecsci.2025.110126","url":null,"abstract":"<div><div>The rolling motion of a ship caused by ocean waves during navigation exhibits non-linear characteristics and large amplitudes, significantly influencing the dynamic behavior of the marine gear transmission system (MGTS). This impact, often leading to considerable vibration and instability, has been largely overlooked in existing research. In this study, ship rolling motion under both regular and irregular waves is analyzed using wave spectrum analysis. The mathematical model of ship rolling is validated through hydrodynamic simulations and ship model experiments. An enhanced dynamic model of the MGTS, incorporating the actual rolling motion, is proposed. This model accounts for gears, shafts, and bearings, including meshing stiffness, transmission errors, nonlinear oil film forces in bearings, and other time-varying internal excitations. The findings reveal that ship rolling motion introduces additional stiffness, gyroscopic effects, and inertia force matrices into the dynamic model, leading to an increase of at least 23.81 % in the response amplitude of the MGTS. This amplifies torsional responses and induces quasi-periodic and chaotic phenomena. Among all wave parameters, the encounter frequency has the most significant impact on the dynamic response of the MGTS. Adjusting the ship's heading angle and navigation speed to align the encounter frequency within a specific range reduces the vibration displacement, velocity, and acceleration amplitudes of the MGTS, thereby improving stability. This study offers theoretical insights into the dynamic behavior of the MGTS during navigation, contributing to the optimization of marine transmission systems and operational strategies.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110126"},"PeriodicalIF":7.1,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143583098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing silo discharge and energy efficiency with vibrated insert","authors":"Guangyang Hong ,&nbsp;Jie Gao ,&nbsp;Qijun Zheng ,&nbsp;Aibing Yu ,&nbsp;Shuang Liu","doi":"10.1016/j.ijmecsci.2025.110128","DOIUrl":"10.1016/j.ijmecsci.2025.110128","url":null,"abstract":"<div><div>The scenarios of particle flow through small orifices are ubiquitous in manufacturing, agriculture, and natural processes. Remarkably, the flow rate can be enhanced by inserting an obstacle above the orifice. In this study, the discrete element method (DEM) is employed to investigate a novel paradigm for modulating particle flow—namely, by applying vibration to the inserted obstacle. Our results demonstrate significant increases in flow rate under vibratory excitation, driven primarily by the interplay between vibration frequency and particle descent dynamics. Granular temperature analysis reveals a localized concentration of kinetic energy near the insert, thereby requiring less energy input compared to conventional wall vibration methods. The effects of insert shape, size, position, as well as vibration amplitude and frequency, are systematically examined. Furthermore, an effective Froude number (<em>Fr</em>*) is introduced to unify the diverse vibrated flow conditions, enabling accurate prediction of discharge rates and identification of critical transitions in energy efficiency. This paradigm offers a practical, energy-efficient solution for optimizing granular flows with wide-reaching implications for bulk solids handling industries.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"291 ","pages":"Article 110128"},"PeriodicalIF":7.1,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143578821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical stability study on vibration responses of casing string systems","authors":"Linshan Qi ,&nbsp;Yiyong Yin ,&nbsp;Liyan Wang ,&nbsp;Congfeng Qu ,&nbsp;Xiujian Xia ,&nbsp;Yongjin Yu ,&nbsp;Binhui Liu ,&nbsp;Shuofei Yang","doi":"10.1016/j.ijmecsci.2025.110119","DOIUrl":"10.1016/j.ijmecsci.2025.110119","url":null,"abstract":"<div><div>The classical transfer matrix method (CTMM) is widely employed for analyzing structural vibrations. However, when applying the CTMM to solve the vibration responses of long casing string systems, severe numerical instability issues arise. To mitigate this problem, this paper introduces a hybrid energy transfer matrix method (HETMM) tailored for solving the vibration responses of casing string systems with distributed elastic supports. This approach significantly enhances the numerical stability compared to CTMM. Firstly, the dynamic model of the casing string system is established, and the correctness and accuracy of the model are verified by tests and numerical calculations. Subsequently, a systematic analysis is conducted to evaluate the influence of various parameters on the stability of the numerical solution for the system's lateral vibration. The research findings indicate that the system length is the primary factor contributing to the instability of the numerical solution. Thus, based on the idea of reducing the characteristic length of the casing string system, the HETMM is proposed to address the lateral vibration of the casing string system. The stability and efficiency of this method in calculating high-frequency and long casing string systems are verified by comparing with other calculation methods. Finally, the frequency domain response of a casing string system with a length of 1450 m is calculated and analyzed. It is found that the number of unit divisions should not be too many or too few, otherwise, it will result in unstable numerical solutions. The appropriate number of units should be determined based on the frequency range of interest. The improved HETMM proposed in this paper is sufficient for solving the lateral vibration response of cementing casing sections ranging from several hundred to several thousand meters. This research provides theoretical guidance for obtaining the response of the long casing string system and optimizing the vibration cementing equipment.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110119"},"PeriodicalIF":7.1,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143601505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic mechanical response and rupture mechanism of freeze-thawed jointed sandstones","authors":"Hao Tan ,&nbsp;Feng Dai ,&nbsp;Yi Liu ,&nbsp;Biao Zhang ,&nbsp;Dingran Song ,&nbsp;Mingdong Wei","doi":"10.1016/j.ijmecsci.2025.110117","DOIUrl":"10.1016/j.ijmecsci.2025.110117","url":null,"abstract":"<div><div>High-altitude cold regions are susceptible to the coupled effects of external freeze-thaw (F-T) and internal joints, leading to a series of rock-related disasters triggered by earthquakes and blasting activities. To investigate the dynamic mechanical response and rupture mechanisms of rock masses in cold regions, this study subjected intact, low-dip, couple-dip, and high-dip jointed specimens to cyclic F-T treatment, followed by dynamic loading using the split Hopkinson pressure bar system. A comprehensive discussion was conducted by integrating micro-parameters, multiple regression, and principal component analysis. The results indicate that F-T weathering accelerates the weakening of rock properties during later stages and lowers the energy threshold for failure, while rock masses containing high-dip joints can more readily meet the crack initiation conditions. In terms of energy, the utilization efficiency of sandstone is minimally impacted by F-T and joints, while the energy dissipation density exhibits a positive correlation with strain rate and a negative correlation with F-T cycles. Additionally, the digital image correlation technique was utilized to investigate the progressive rupture behavior of sandstone. Qualitatively, the technique elucidated the transition from brittleness to ductility induced by F-T cycles, as well as the shift from tensile to shear fracturing associated with joint geometries. Quantitatively, the analysis revealed a power-law acceleration pattern of high-strain areas prior to sandstone failure. Furthermore, on one hand, micro-damage analysis was employed to illustrate the synergistic deterioration of physical and mechanical properties in cold region rocks. On the other hand, a predictive model for dynamic strength was developed, revealing that fragmentation states are predominantly influenced by strain rate and secondarily by F-T damage. This overcomes the limitations of conventional methods that rely on single-parameter thresholds to distinguish failure modes. The present study establishes a comprehensive framework for evaluating dynamic instability mechanisms of jointed rocks in cold regions.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110117"},"PeriodicalIF":7.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143592352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tunable anisotropy in lattice structures via deep learning-based optimization","authors":"Chaewon Park,&nbsp;Sangryun Lee","doi":"10.1016/j.ijmecsci.2025.110121","DOIUrl":"10.1016/j.ijmecsci.2025.110121","url":null,"abstract":"<div><div>The advancements in additive manufacturing have sparked extensive exploration of lattice truss structures, renowned for their exceptional properties suitable for diverse engineering applications. Achieving a high mechanical modulus while maintaining low density poses a challenge, prompting numerous studies aimed at addressing the trade-off relationship between porosity and modulus. However, most efforts have concentrated on enhancing modulus for unidirectional loads, a limitation in addressing the random loads commonly found in industrial settings. To tackle this issue, our study designs lattice structures that achieve significantly reduced anisotropy at low densities, employing a combination of neural networks and genetic optimization. This novel approach allows for the efficient derivation of optimized models. Importantly, our approach solely alters the beam shapes within the basic lattice structure configurations, facilitating manufacturability without reducing average stiffness. Furthermore, our research elucidates the mechanism behind shape-dependent anisotropy and confirms these findings through both numerical and experimental results, offering insights into the design limitations and potential for next-generation lightweight structures.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110121"},"PeriodicalIF":7.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143578195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inertial amplification stiffened meta-panels for low-frequency sound insulation","authors":"Yonghang Sun ,&nbsp;Yapeng Li ,&nbsp;Gongshuo Zhang ,&nbsp;Heow Pueh Lee ,&nbsp;Hui Zheng ,&nbsp;Fucai Li","doi":"10.1016/j.ijmecsci.2025.110116","DOIUrl":"10.1016/j.ijmecsci.2025.110116","url":null,"abstract":"<div><div>Stiffened structures have been widely employed in various engineering fields, including aerospace, large aircrafts, and underwater vehicles, due to their high specific stiffness and specific strength. However, improving their low-frequency sound insulation using local resonance metamaterials is challenging, particularly when additional mass is constrained. This study introduces an inertial amplification (IA) stiffened meta-panel to enhance the low-frequency sound insulation of stiffened structures. A semi-analytical method is developed to model the proposed structure and to calculate the band structures and transmission loss (TL). To impose periodic boundary conditions, a collocation-based Lagrange multiplier method is introduced, using a series of pre-selected collocation points along unit-cell boundaries. Numerical validations of the proposed model and method demonstrate their feasibility and accuracy in computing both band structures and TL. Theoretical results reveal that the IA effect contributes to the formation of bandgaps in the band structures and the TL peaks within the low-frequency range. Parametric studies further show that as the IA ratio increases, IA and Bragg bandgaps are reversed—a trend also observed with variations in the length of cantilever beams and the height of stiffeners. However, increasing the height of stiffeners enhances the bending stiffness of the unit cell, leading to a high-frequency shift of Bragg bandgaps. Laboratory measurements of TL, conducted using the reverberation chamber method and the sound box method, confirm the effectiveness of the proposed meta-panel and the computational method, revealing their potential for engineering applications in low-frequency sound insulation.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110116"},"PeriodicalIF":7.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143578133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy harvesting of unequal-height cylindrical FIV considering wind direction","authors":"Bowen Tang ,&nbsp;Xiantao Fan ,&nbsp;Jiawei Wang ,&nbsp;Hewei Yang ,&nbsp;Rui Bai ,&nbsp;Xiaoyang Yu ,&nbsp;Wei Tan","doi":"10.1016/j.ijmecsci.2025.110118","DOIUrl":"10.1016/j.ijmecsci.2025.110118","url":null,"abstract":"<div><div>To improve the performance of flow-induced vibration (FIV) energy harvesters, we propose the use of unequal-height tandem cylinders. Specifically, we design cylinder models with height ratios (<em>h</em>/<em>H</em> = 0.2, 0.4, 0.6, 0.8, 1.0) and conduct wind tunnel tests under different wind directions and spacing ratios. Our approach enhances the understanding of how wind direction impacts the vibration and energy harvesting performance of unequal-height tandem cylinders. Through wind tunnel experiments, we identify nine distinct vibration modes, which are further analyzed using wavelet transforms for precise frequency identification. Notably, at the spacing ratio <em>l</em> = 1.2, we observe a strong coupling effect between the upstream and downstream cylinders. For shorter cylinders, significant vibration amplitudes in vibration modes IV and VII remain stable despite changes in wind direction, a phenomenon we term the \"short cylinder instability effect\". This effect is consistent across all wind conditions tested. Through theoretical analysis, the electromechanical prediction model of coupled vortex-induced vibration and wake-induced galloping is established, which is in good agreement with the experimental results. In addition, at <em>h</em>/<em>H</em> = 0.4, vibration is suppressed in the upwind configuration, while in the downwind configuration, the maximum voltage generated at <em>l</em> = 2.5 is 9.602 V, which is 204 % higher than that of equal-height cylinders. To better understand the effects of wind direction and height variations, we also perform computational fluid dynamics (CFD) simulations. These simulations reveal how vortex shedding at a microscopic level contributes to the shielding effects caused by changes in wind direction and cylinder height. The CFD simulations further reveal how wind direction and cylinder height influence vortex shedding and shielding effects.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110118"},"PeriodicalIF":7.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143563624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origami-inspired highly impact-resistant metamaterial with loading-associated mechanism and localization mitigation","authors":"Shujian Yao ,&nbsp;Hui Zhou ,&nbsp;Tianyu Gao ,&nbsp;Feipeng Chen ,&nbsp;Zhifu Wang ,&nbsp;Kai Liu","doi":"10.1016/j.ijmecsci.2025.110114","DOIUrl":"10.1016/j.ijmecsci.2025.110114","url":null,"abstract":"<div><div>Breakthroughs in highly impact-resistant materials and structures are crucial in engineering fields such as military protection, transportation and architecture. Nevertheless, the resisting efficiency of conventional materials has progressively fallen short of increasing advanced engineering demands. In this study, drawing inspiration from the flexibility and versatility of cutting-edge origami design, a novel metamaterial with enhanced impact resistance capabilities is proposed. The core principle of microstructural design is based on origami kinematics, where the constrained degrees of freedom create interrelated movements and deformations across various components. It gives a triaxial loading-associated energy absorption mechanism where the periodic units of the metamaterial exhibit strong resistance and high internal forces in all directions when subjected to any uniaxial load, resulting in more extensive deformation and strain localization mitigation. For further mechanism analysis, an origami metamaterial specimen is fabricated using Selective Laser Melting (SLM) 3D printing technology with 6061 aluminum alloy. A light-gas gun system is used for the test of specimen impact resistance, resisting high-kinetic-energy projectile above 500J. A corresponding simulation model is also constructed to investigate the impact behavior. The results demonstrate that the origami metamaterial exhibits exceptional impact resistance, e.g., higher ballistic limit and higher specific energy absorption (SEA). Overall, this work reveals a high impact energy absorption mechanism based on origami kinematics, which further contributes to the mechanistic interdisciplinary study of origami geometry and impact dynamics.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110114"},"PeriodicalIF":7.1,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repair-mechanism and strategy-customization during micro-milling of flawed potassium dihydrogen phosphate","authors":"Hongqin Lei ,&nbsp;Zhaoyang Yin ,&nbsp;Linjie Zhao ,&nbsp;Jian Cheng ,&nbsp;Mingjun Chen ,&nbsp;Qi Liu ,&nbsp;Dinghuai Yang ,&nbsp;Guang Chen ,&nbsp;Jianrui Hu ,&nbsp;Jixiang Chen","doi":"10.1016/j.ijmecsci.2025.110110","DOIUrl":"10.1016/j.ijmecsci.2025.110110","url":null,"abstract":"<div><div>Using ball-end milling to prepare high-quality Cone mitigation pits (CMP) is the best method to effectively remove surface flaws and realize the recycling of large-aperture potassium dihydrogen phosphate (KDP) optics. However, micro-flaws with complex geometry would change the tool-workpiece thermal load in the repair process, affecting the surface quality. In this study, the models of specific cutting energy (SCE) and the maximum uncut chip thickness (UCT_max) considering the surface flaw dimension are constructed. The impact of different micro-flaws on the energy consumption and brittle-ductile transition is investigated. The results show that plastic scratches could reduce UCT_max from 356.4 to 206.3 nm, leading to the rise of SCE and improvement of surface quality. Surface protuberances could increase UCT_max, causing a decrease in SCE from 123.3 to 43.1 GPa and a ductile-to-brittle transition. For cracks and convex scratches, there are no significant variations in SCE and surface roughness (<em>Sa</em>) in the repair process. Furthermore, targeted repair strategies are proposed for two surface flaws. For plastic scratches, priority should be given to ensuring that the flawless zones are in ductile removal (Strategy Ⅰ). In the contrary, for surface protuberances, the flawed zones should first be ensured to be in ductile removal (Strategy Ⅱ). After repair, average <em>Sa</em> decreases from 111.6 to 46.7 nm, and Laser damage resistance of KDP optics increases from 7.1 to 32.8 J/cm², which can be restored to 95 % of ideal surfaces. This work can offer theoretical guidance and technical support for the recycling of high-performance KDP optics.</div></div>","PeriodicalId":56287,"journal":{"name":"International Journal of Mechanical Sciences","volume":"290 ","pages":"Article 110110"},"PeriodicalIF":7.1,"publicationDate":"2025-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}