Procedia CIRP最新文献_第9页

Forward design of temperature field in laser-assisted milling of Ti6Al4V alloy through numerical simulation 通过数值模拟对Ti6Al4V合金激光辅助铣削温度场进行了正向设计

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.053

Xin Liu, Hongguang Liu, Shijia Shi, Binbin Xu, Jun Zhang

{"title":"Forward design of temperature field in laser-assisted milling of Ti6Al4V alloy through numerical simulation","authors":"Xin Liu, Hongguang Liu, Shijia Shi, Binbin Xu, Jun Zhang","doi":"10.1016/j.procir.2025.02.053","DOIUrl":"10.1016/j.procir.2025.02.053","url":null,"abstract":"<div><div>Laser-assisted machining (LAM) is an advanced technique, which can significantly reduce cutting forces and improve machining efficiency of difficult-to-cut materials by preheating the local area. A crucial step for obtaining ideal machinability is to control the temperature field by modulating process parameters. In this paper, by quantitative characterization of the output laser beam quality, an analytical model is adopted to characterize the temperature field induced by the moving laser source. Following, a temperature-controlling strategy is proposed for adapting the moving path of the laser source to obtain a uniform temperature distribution within the cutting area. Then, based on the classical oblique cutting model, an analytical force model of LAM is developed sequentially coupled with the optimized laser moving path to predict the milling forces. The proposed forces model takes into account the effects of laser heating and material softening. Thus, the controlling strategy of the temperature field was established. Furthermore, the proposed strategy is verified by the variation of cutting forces during the face-milling of Ti6Al4V. The results show that the proposed strategy can significantly reduce the milling forces by over 10%. The developed force model can provide acceptable predicted accuracy, which reflects the impacts of temperature field distribution on cutting forces. In summary, the proposed strategy can effectively regulate the preheating temperature, providing a theoretical way for the forward design of laser-heating parameters.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 304-309"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759367","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}

引用次数: 0

Modelling the energy consumption of an industrial robot with different types of trajectory for machining tasks 对具有不同轨迹类型的工业机器人加工任务的能量消耗进行了建模

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.054

Florian Delooz , Valentin Dambly , François Ducobu , Édouard Rivière-Lorphèvre , Bryan Olivier

{"title":"Modelling the energy consumption of an industrial robot with different types of trajectory for machining tasks","authors":"Florian Delooz , Valentin Dambly , François Ducobu , Édouard Rivière-Lorphèvre , Bryan Olivier","doi":"10.1016/j.procir.2025.02.054","DOIUrl":"10.1016/j.procir.2025.02.054","url":null,"abstract":"<div><div>Industrial robots are being used more and more for machining operations, in particular due to their agility in the case of products with complex geometries, as well as their adaptability across various applications. For some years, as industries become more ecologically conscious, energy consumption (EC) during operations becomes an important consideration. This growing awareness motivates the need for models that monitor the EC of a robot during machining operations. Firstly, the robot multibody model used in the simulations will be completely described. The computational methodology used to calculate EC during these machining tasks will also be outlined, including a discussion of the motors model applied in the simulations. Then, to validate the established model, an initial simulation will be carried out using a simple general case, depicting a straight line trajectory, to demonstrate the effectiveness of the model used. Finally, other relevant simulation tests will be presented for distinct cases: a smooth and continuous machining trajectory with variations in the curve parameter and the followed axes. The results of these numerical tests provide insights into how different machining strategies impact EC, providing guidelines for optimizing robot operation in an environmentally conscious industrial context.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 310-315"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759368","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}

引用次数: 0

An Apparatus Design for Multiaxial Ductile Fracture: Application to AISI1045 多轴韧性断裂装置设计：在AISI1045上的应用

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.035

Afonso V.L. Gregorio , Tiago E.F. Silva , José C. Outeiro , Carlos E.H. Ventura , Pedro Areias , Abílio M.P. de Jesus , Pedro Rosa

{"title":"An Apparatus Design for Multiaxial Ductile Fracture: Application to AISI1045","authors":"Afonso V.L. Gregorio , Tiago E.F. Silva , José C. Outeiro , Carlos E.H. Ventura , Pedro Areias , Abílio M.P. de Jesus , Pedro Rosa","doi":"10.1016/j.procir.2025.02.035","DOIUrl":"10.1016/j.procir.2025.02.035","url":null,"abstract":"<div><div>Metal cutting involves extensive plastic deformation as the workpiece material flows through the shear plane, promoting mechanisms of initiation, coalescence, and propagation of cracks. This the largest plastic deformation that it can withstand, above those of tensile and compression tests. Such condition ultimately leads to the onset of an ever-present crack just ahead of the cutting edge that provides the separation mechanism necessary to form the chip. However, it is neither easy nor simple to measure the fraction of the total energy involved in the material separation mechanism and its correlation with operating conditions.</div><div>In this research, a new design of a multiaxial tool for determining mode II ductile fracture toughness is proposed. This testing tool is composed of several hydraulic and pneumatic actuators that allow a shearing punch to act against double-notched prismatic specimens with superimposed orthogonal load, yielding a wide range of stress triaxialities. This load can vary from the compressive to tensile yield stress of the material. Thus, allowing the influence analysis of the stress state on the mechanical response of ductile materials, like that experienced on the shear plane of metal cutting due to rake face angle variation. Experiments performed in AISI 1045 give support to the presentation and allow a better understanding of the influence of the superimposed pressure on fracture toughness of ductile metals.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 197-202"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759555","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}

引用次数: 0

DEM Simulation of Abrasive Brushing Processes on Additively Manufactured Workpieces 增材制造工件磨料刷加工过程的DEM模拟

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.036

Anton Hoyer , Eckart Uhlmann

{"title":"DEM Simulation of Abrasive Brushing Processes on Additively Manufactured Workpieces","authors":"Anton Hoyer , Eckart Uhlmann","doi":"10.1016/j.procir.2025.02.036","DOIUrl":"10.1016/j.procir.2025.02.036","url":null,"abstract":"<div><div>Brushing with bonded abrasives is a finishing process mainly used for deburring, edge rounding, and surface roughness reduction. The brushing tools consist of flexible polymer filaments embedded with abrasive grains, allowing them to adapt to complex workpiece shapes. However, interactions between filaments lead to complex motion, chipping, and wear behaviors, making it difficult to predict work results. The discrete element method (DEM) has been shown to be effective in simulating process forces, contact areas, and filament interactions on flat workpieces. Consequently, this article focuses on processing geometrically complex workpieces, particularly additively manufactured turbine fan blades (Ni-Cr-Co), using round brushes with bonded silicon carbide. First, a vectorized iterative method is introduced to generate artificial filament patterns, enhancing DEM simulation accuracy compared to state-of-the-art filament pattern models. Subsequently, dry brushing experiments are carried out on a fan blade feature demonstrator, aiming to achieve homogeneous roughness reduction. The qualitative analysis of the contact surface suggests that results from DEM simulations can reduce the need for costly technological investigations and prototypes.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 203-208"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759556","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}

引用次数: 0

Modeling Process Forces in CFRP Grinding: Influence of Cutting Materials and Coolant on Process Force Behavior CFRP磨削过程力建模：切削材料和冷却剂对过程力行为的影响

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.004

Alexander Brouschkin , Carsten Möller , Jan Hendrik Dege

{"title":"Modeling Process Forces in CFRP Grinding: Influence of Cutting Materials and Coolant on Process Force Behavior","authors":"Alexander Brouschkin , Carsten Möller , Jan Hendrik Dege","doi":"10.1016/j.procir.2025.02.004","DOIUrl":"10.1016/j.procir.2025.02.004","url":null,"abstract":"<div><div>Carbon Fibre Reinforced Polymer (CFRP) is favoured for its high strength to weight ratio, excellent directional mechanical and thermal properties, and the ability to be optimized in the direction of stress or heat flow. These properties make it ideal for power transmission applications. Meeting the high-quality requirements in this area requires a precise grinding process and a thorough understanding of cutting forces, which are influenced by different factors e.g. coolant usage, or cutting material. However, machining unidirectional CFRP is challenging due to its anisotropic behaviour, resulting in different machining forces for identical parameters with different fibre orientations.</div><div>A universal process-independent model was recently developed to describe the engagement conditions during oblique cutting of unidirectional CFRP by introducing the spatial fibre cutting angle θ<sub>0</sub> and the spatial engagement angle φ<sub>0</sub>. Using this description, an universal mechanistic machining force model for grinding of CFRP was developed.</div><div>In the paper, an extension of the model of oblique cutting for grinding is extended and experimentally verified, taking into account additional parameters e.g. coolant and cutting material. Therefore, the process forces were measured as a function of the spatial fibre cutting angles for different cutting materials, both with and without the use of coolant.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 14-19"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759650","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}

引用次数: 0

Numerical chip formation simulations of AISI 304 steel with varying cutting tools 不同刀具下AISI 304钢切屑形成的数值模拟

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.024

Erik Krumme , Kai Donnerbauer , Jannis Saelzer , Andreas Zabel , Frank Walther

{"title":"Numerical chip formation simulations of AISI 304 steel with varying cutting tools","authors":"Erik Krumme , Kai Donnerbauer , Jannis Saelzer , Andreas Zabel , Frank Walther","doi":"10.1016/j.procir.2025.02.024","DOIUrl":"10.1016/j.procir.2025.02.024","url":null,"abstract":"<div><div>Numerical chip formation simulations are a promising approach for determining the tool wear behavior of cemented carbide tools in a resource-efficient way. To achieve a high prediction quality of the chip formation simulations, suitable input data must be identified with regard to the friction and flow stress behavior of the material. Therefore, within this work, the flow stress and frictional behavior was first determined experimentally. Based on the investigations a numerical chip formation simulation was parameterized for future wear simulations. Beside the Split Hopkinson Pressure Bar (SHPB) test, quasi-static compression tests were conducted to characterize the flow stress behavior of the workpiece material. Furthermore, the frictional behavior was investigated using a special machine tool for fundamental chip formation analysis, taking into consideration the relative speed and measuring the contact temperatures for uncoated and TiAlN coated cutting tools. Based on the experimental data, different models for flow stress and friction were parameterized. Subsequently the models were implemented into the numerical chip formation simulation to model the thermo-mechanical load collective, whereas the results by means of the resulting forces were validated by orthogonal cutting tests. The parameterization of the friction models led to an improved prediction quality of the numerical chip formation simulation with regard to the cutting forces in comparison to a constant friction model.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 132-137"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759652","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}

引用次数: 0

Predictive Maintenance of Wire Electrical Discharge Machining Using Long Short-Term Memory Networks for Improved Process Control 基于长短期记忆网络的线材电火花加工预测性维护改进过程控制

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.030

Namadi Vinod Kumar, D. Chakradhar

{"title":"Predictive Maintenance of Wire Electrical Discharge Machining Using Long Short-Term Memory Networks for Improved Process Control","authors":"Namadi Vinod Kumar, D. Chakradhar","doi":"10.1016/j.procir.2025.02.030","DOIUrl":"10.1016/j.procir.2025.02.030","url":null,"abstract":"<div><div>Time series forecasting and anomaly detection are becoming essential in smart manufacturing for prognostics and health management of a machine, especially where traditional methods struggle with the analysis of high frequency data. This study uses Long Short-Term Memory (LSTM) networks for detecting and predicting anomalies in wire electrical discharge machining (WEDM), specifically focusing on events like no-sparking and wire breaks. In closed-loop forecasting continuous numerical predictions are challenging in high-frequency data analysis, so a centroid-based approach was chosen. This method simplifies forecasting by using representative feature values that highlight important class differences in the data. With this closed-loop LSTM and centroid approach, the model effectively forecasts machine states up to five seconds ahead; a useful time frame for detecting critical issues such as wire breakage and no sparking before they impact operations. The results show that this method, combined with LSTM ability to capture time patterns, can handle complex, shifting conditions in WEDM. This approach could improve productivity and reduce unexpected downtime in smart manufacturing, offering a practical and efficient way to monitor and predict machine conditions.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 167-172"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759658","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}

引用次数: 0

Investigation of biological tissue cutting for minimal tissue damage using finite element simulation 利用有限元模拟研究如何切割生物组织以实现最小的组织损伤

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.085

Urara Satake , Ryusei Senda , Ryutaro Sambe , Toshiyuki Enomoto

{"title":"Investigation of biological tissue cutting for minimal tissue damage using finite element simulation","authors":"Urara Satake , Ryusei Senda , Ryutaro Sambe , Toshiyuki Enomoto","doi":"10.1016/j.procir.2025.02.085","DOIUrl":"10.1016/j.procir.2025.02.085","url":null,"abstract":"<div><div>In surgical cutting procedures for biological soft tissues, it is crucial to minimize tissue damage. However, before cut initiation, tissues undergo significant deformation due to their elastomeric properties. This deformation can cause tissue damage and increase the risk of complications, particularly in neurosurgery and ophthalmic surgery. The cut-initiation ability of a process must be improved to reduce the depth of the blade indentation required for cut initiation. Adding a slicing motion to the blade indentation has been found to enhance the cut initiation; however, the specific advantages of this method over pure indentation are not fully understood. This study aims to analyze the effects of cutting parameters, including blade motion, on the initiation of cuts in elastomeric solids, such as biological soft tissues, by examining the strain states beneath the blade that trigger cut initiation. During cutting, deep indentation by a sharp blade causes significant geometric nonlinearity, displacing the workpiece surface along the blade surface. These blade–workpiece interfacial interactions likely affect the strain states beneath the blade. Therefore, this study uses finite element simulations to examine the blade–workpiece interfacial interactions and their relation to the strain states, focusing on the influence of interfacial friction. The results indicate that the distribution of in-plane stretch along the blade surface of the workpiece is crucial for determining the strain states and the resulting cut-initiation ability. The improved cut initiation achieved by introducing a slicing motion to blade indentation can be attributed to the enhanced distribution of in-plane surface stretch.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 495-500"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759179","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}

引用次数: 0

Sensitivity analysis for considering the process dynamics during the calibration of process force models 校准过程力模型时考虑过程动态的敏感性分析

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.072

Melina Wenzel , Daniel Welling , Dirk Biermann , Petra Wiederkehr

{"title":"Sensitivity analysis for considering the process dynamics during the calibration of process force models","authors":"Melina Wenzel , Daniel Welling , Dirk Biermann , Petra Wiederkehr","doi":"10.1016/j.procir.2025.02.072","DOIUrl":"10.1016/j.procir.2025.02.072","url":null,"abstract":"<div><div>When analyzing milling processes, various characteristics such as process forces and tool deflections can be investigated using process simulations. The analysis of cutting forces is subject to the dynamic effects of the tool and workpiece, whereby the force measurement technology used has a further influence due to its own modal properties and its specific force transfer behavior. Particularly during finishing with spherical milling tools, the variation of radius and helix angle along the cutting edge leads to variations of the engagement situation and effective cutting speed. These different geometric properties and orientations of the tools infuence the process forces and dynamics and their interactions. Due to various influences on force measurements and dynamic superimposition, a higher model quality can be achieved through a sophisticated calibration methodology.</div><div>In this paper, a methodology is presented in which the effects of tool dynamics are included in the calibration of force model coefficients to improve the accuracy of the resulting model. To this end, the inclusion of non-stationary tooth engagements during run-in and run-outs are considered, where process dynamics are more prevalent. For this analysis the cutting edge of spherical tools was divided into sections using confocal microscopy, which were replicated as analogous tools using cylindrical end mills. Peripheral milling tests with different process scenarios were conducted with these analogy tools, which had different geometric properties, in order to generate an experimental database. Based on this data, a sensitivity analysis was carried out for process force calibration taking process dynamics into account.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 418-423"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759210","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}

引用次数: 0

Improved coolant channel flow efficiency for grooving tools through simulation and additive manufacturing 通过模拟和增材制造提高切槽工具的冷却剂通道流动效率

Procedia CIRP Pub Date : 2025-01-01 DOI: 10.1016/j.procir.2025.02.060

Patrick Fischmann, Sebastian Galland, Frederik Zanger

{"title":"Improved coolant channel flow efficiency for grooving tools through simulation and additive manufacturing","authors":"Patrick Fischmann, Sebastian Galland, Frederik Zanger","doi":"10.1016/j.procir.2025.02.060","DOIUrl":"10.1016/j.procir.2025.02.060","url":null,"abstract":"<div><div>Laser-based powder bed fusion for metals (PBF-LB/M) enables the production of complex external and internal shapes. This enables tool production with targeted supply of cooling lubricant. The simulative channel design and the resulting increase in coolant flow after production are the focus of this work. The optimization process is illustrated using a commercially available grooving tool with three channels and four outlets. Accordingly, a simulation was conducted to investigate and ultimately reduce the pressure loss between the inlet and outlet of the channel. This approach resulted in a calculated reduction in pressure loss of up to 97 % in the channels, as well as increased uniformity of the stream at the coolant outlet. After production of the optimized tool using PBF-LB/M, a volume flow measurement was conducted under varying coolant pressure. Fluctuations between the different tool holders were observed, which can be attributed to the additive manufacturing process and resulting spatter. In relation to all cooling channels in the grooving tool, an increase in the flow rate of up to 6% was determined.</div></div>","PeriodicalId":20535,"journal":{"name":"Procedia CIRP","volume":"133 ","pages":"Pages 346-351"},"PeriodicalIF":0.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759267","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}

引用次数: 0