首页 > 最新文献

2017 International Conference on Mechanical, System and Control Engineering (ICMSC)最新文献

英文 中文
Simulation study on vibration characteristics of excitation valve 激励阀振动特性仿真研究
Pub Date : 2017-05-01 DOI: 10.1109/ICMSC.2017.7959448
Wu Wanrong, Wu Weiwei, Huang Qian, Wang Songlai
The traditional excitation system usually adopts the eletro-hydraulic excitation valve, of which the structure is complicated and requires externally being connected to the servo motor and control system, but cannot meet the requirements of high frequency and high flow. So a cartridge vibration valve is proposed. The valve has a simple structure, which is mainly composed of four two-way cartridge valves, a two-position four-way hydraulic control directional valve and two variable throttle orifices. Its frequency modulation mode is simple, and it can achieve high-frequency commutation and large-flow output. To study the effect of the parameters on the vibration characteristics of the vibration valve, the mathematical model and AMESim simulation model were established. The result shows that: the excitation frequency increases with the increasing of the working pressure, the area ratio and the spring stiffness of the two-way cartridge valve. Adjusting the orifice diameter and the working pressure can regulate the excitation frequency.
传统的励磁系统通常采用电液励磁阀,其结构复杂,需要外部连接伺服电机和控制系统,但不能满足高频、大流量的要求。为此,提出了一种插装式振动阀。该阀结构简单,主要由四个双向插装阀、一个二位四通液压控制换向阀和两个可变节流孔组成。其调频方式简单,可实现高频换向和大流量输出。为研究各参数对振动阀振动特性的影响,建立了振动阀的数学模型和AMESim仿真模型。结果表明:激励频率随工作压力、面积比和二通插装阀弹簧刚度的增大而增大;调节节流孔直径和工作压力可以调节励磁频率。
{"title":"Simulation study on vibration characteristics of excitation valve","authors":"Wu Wanrong, Wu Weiwei, Huang Qian, Wang Songlai","doi":"10.1109/ICMSC.2017.7959448","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959448","url":null,"abstract":"The traditional excitation system usually adopts the eletro-hydraulic excitation valve, of which the structure is complicated and requires externally being connected to the servo motor and control system, but cannot meet the requirements of high frequency and high flow. So a cartridge vibration valve is proposed. The valve has a simple structure, which is mainly composed of four two-way cartridge valves, a two-position four-way hydraulic control directional valve and two variable throttle orifices. Its frequency modulation mode is simple, and it can achieve high-frequency commutation and large-flow output. To study the effect of the parameters on the vibration characteristics of the vibration valve, the mathematical model and AMESim simulation model were established. The result shows that: the excitation frequency increases with the increasing of the working pressure, the area ratio and the spring stiffness of the two-way cartridge valve. Adjusting the orifice diameter and the working pressure can regulate the excitation frequency.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127853584","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: 1
A remote health condition monitoring system based on compressed sensing 基于压缩感知的远程健康状态监测系统
Pub Date : 2017-05-01 DOI: 10.1109/ICMSC.2017.7959483
Jie Liu, Youmin Hu, Yanglong Lu, Yan Wang, L. Xiao, Kunming Zheng
Data-driven health condition monitoring has received increasing attentions. However, the bandwidth of transmission channels imposes the limit on the amount of sensor data to be used in remote condition monitoring systems in real-time applications. In this paper, a remote health condition monitoring (RHCM) method based on compressed sensing (CS) is proposed for machine state classification and signal reconstruction. Compressed sensor signals can be directly used to identify different machine states based on a pre-constructed dictionary without the need of traditional feature extraction process. Alternatively, the complete signals can also be reconstructed from the compressed signals and traditional classification approaches can be applied. A case study based on rolling bearing is used to show that the proposed RHCM method can effectively recognize and classify the machine states under different operation conditions using low-volume sensor signals, and the reconstructed signals are accurate enough for post-evaluation or quality assessment of on-site machine process.
数据驱动的健康状态监测越来越受到人们的关注。然而,传输信道的带宽限制了远程状态监测系统中实时应用的传感器数据量。提出了一种基于压缩感知(CS)的远程健康状态监测方法,用于机器状态分类和信号重构。压缩后的传感器信号可以直接用于基于预构造字典的机器状态识别,而不需要传统的特征提取过程。或者,也可以从压缩后的信号重构完整的信号,并采用传统的分类方法。以滚动轴承为例,表明所提出的RHCM方法可以利用小体积传感器信号对不同运行条件下的机器状态进行有效识别和分类,重构后的信号足够准确,可用于现场机器过程的后评价或质量评价。
{"title":"A remote health condition monitoring system based on compressed sensing","authors":"Jie Liu, Youmin Hu, Yanglong Lu, Yan Wang, L. Xiao, Kunming Zheng","doi":"10.1109/ICMSC.2017.7959483","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959483","url":null,"abstract":"Data-driven health condition monitoring has received increasing attentions. However, the bandwidth of transmission channels imposes the limit on the amount of sensor data to be used in remote condition monitoring systems in real-time applications. In this paper, a remote health condition monitoring (RHCM) method based on compressed sensing (CS) is proposed for machine state classification and signal reconstruction. Compressed sensor signals can be directly used to identify different machine states based on a pre-constructed dictionary without the need of traditional feature extraction process. Alternatively, the complete signals can also be reconstructed from the compressed signals and traditional classification approaches can be applied. A case study based on rolling bearing is used to show that the proposed RHCM method can effectively recognize and classify the machine states under different operation conditions using low-volume sensor signals, and the reconstructed signals are accurate enough for post-evaluation or quality assessment of on-site machine process.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133750889","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: 1
The research process of the finishing strengthening centrifugal and rotary processing method of parts considering the reliability assurance of the technology process 考虑工艺过程可靠性保证的零件精加工强化离心旋转加工方法的研究过程
Pub Date : 2017-05-01 DOI: 10.1109/icmsc.2017.7959437
M. Tamarkin, E. Tischenko, D. Kazakov
The article introduces the results of process research of the centrifugal and rotary processing of parts of steel and nonferrous alloys in the medium of steel spheres. The complex of the reliability indicators forming models of a technology process which allows providing an increase in the efficiency and the achievement of set size and stability of quality parameters of a workpiece has been received. The techniques of the technology process design have been developed.
本文介绍了在钢球介质中对钢及有色合金零件进行离心旋转加工的工艺研究结果。可靠性指标的复杂形成模型的一个技术过程,允许提供提高效率和实现设定的尺寸和工件的质量参数的稳定性。开发了工艺流程设计技术。
{"title":"The research process of the finishing strengthening centrifugal and rotary processing method of parts considering the reliability assurance of the technology process","authors":"M. Tamarkin, E. Tischenko, D. Kazakov","doi":"10.1109/icmsc.2017.7959437","DOIUrl":"https://doi.org/10.1109/icmsc.2017.7959437","url":null,"abstract":"The article introduces the results of process research of the centrifugal and rotary processing of parts of steel and nonferrous alloys in the medium of steel spheres. The complex of the reliability indicators forming models of a technology process which allows providing an increase in the efficiency and the achievement of set size and stability of quality parameters of a workpiece has been received. The techniques of the technology process design have been developed.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131414950","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: 3
Comparison of identification algorithms based on the combining maximum principle and the regularization 结合极大值原理与正则化方法的辨识算法比较
Pub Date : 2017-05-01 DOI: 10.1109/ICMSC.2017.7959474
A. Kostoglotov, Oksana Andreevna Kostoglotova, Igor Deryabkin, Igor Evgenevich Kirillov, S. Lazarenko
The variational methods of parametric identification which use the physical features of the studied systems in the form of the Hamilton — Ostrogradskii variational principle are studied. On this basis the identification algorithms resistant to measurement noise and having high convergence rate of their estimates to the actual values are produced. This is confirmed by comparing the results of mathematical simulation of the developed algorithms with the Kalman filter.
利用所研究系统的物理特性,以Hamilton - Ostrogradskii变分原理的形式研究了参数辨识的变分方法。在此基础上,提出了抗测量噪声、估计值与实际值收敛率高的识别算法。通过将所开发算法的数学模拟结果与卡尔曼滤波进行比较,证实了这一点。
{"title":"Comparison of identification algorithms based on the combining maximum principle and the regularization","authors":"A. Kostoglotov, Oksana Andreevna Kostoglotova, Igor Deryabkin, Igor Evgenevich Kirillov, S. Lazarenko","doi":"10.1109/ICMSC.2017.7959474","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959474","url":null,"abstract":"The variational methods of parametric identification which use the physical features of the studied systems in the form of the Hamilton — Ostrogradskii variational principle are studied. On this basis the identification algorithms resistant to measurement noise and having high convergence rate of their estimates to the actual values are produced. This is confirmed by comparing the results of mathematical simulation of the developed algorithms with the Kalman filter.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124795147","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
Discrete Hopfield neural network approach for crane safety evaluation 离散Hopfield神经网络方法在起重机安全评价中的应用
Pub Date : 2017-05-01 DOI: 10.1109/ICMSC.2017.7959439
Jing Gan
The complex mechanical structure and working characteristics of crane determine it is a kind of construction machinery with larger risk factors. In order to ensure the safety and reliability of the crane during operation process, also avoid serious failure which affects the efficiency and progress of the engineering project, this paper uses discrete Hopfield neural network approach to evaluate and monitor the running state of the crane. The experimental results show that the discrete Hopfield neural network mode can accurately evaluate the running state of the crane, and thus provides an effective technical way to improve its security and reliability.
起重机复杂的机械结构和工作特点决定了它是一种危险因素较大的工程机械。为了保证起重机在运行过程中的安全可靠,避免严重故障影响工程项目的效率和进度,本文采用离散Hopfield神经网络方法对起重机的运行状态进行评估和监测。实验结果表明,离散Hopfield神经网络模型能够准确地评估起重机的运行状态,从而为提高起重机的安全性和可靠性提供了有效的技术途径。
{"title":"Discrete Hopfield neural network approach for crane safety evaluation","authors":"Jing Gan","doi":"10.1109/ICMSC.2017.7959439","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959439","url":null,"abstract":"The complex mechanical structure and working characteristics of crane determine it is a kind of construction machinery with larger risk factors. In order to ensure the safety and reliability of the crane during operation process, also avoid serious failure which affects the efficiency and progress of the engineering project, this paper uses discrete Hopfield neural network approach to evaluate and monitor the running state of the crane. The experimental results show that the discrete Hopfield neural network mode can accurately evaluate the running state of the crane, and thus provides an effective technical way to improve its security and reliability.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"1632 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132155085","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: 6
Algorithm for sine wave cure fit based on frequency precise estimation 基于频率精确估计的正弦波拟合算法
Pub Date : 2017-05-01 DOI: 10.1109/ICMSC.2017.7959501
Xuanze Wang, Yi Luo, Zhongsheng Zhai, Liangen Yang, Tao He
In the process of curve fitting, the unknown relationship between the data sampling rate and the frequency of the measured signal as well as signal's frequency fluctuations can cause remarkable error. In this paper, a sine curve fitting algorithm with frequency precise estimation is proposed to solve this problem. Firstly, ellipse fitting algorithm is used to estimate the measured signal frequency. On the basis of this, the three-parameter sine fitting calculation based on the least squares method is applied to the sampling data, and the accuracy of the sine curve fitting result is improved. The experimental results show that the algorithm proposed in this paper can avoid the problem of frequency fluctuation and error caused by the unknown relationship between the sampling frequencies. Moreover, the fitting has a good randomness after frequency estimation, and the fitting result has nothing to do with the signal amplitude. Compared without frequency accurate estimation, the fitting error is greatly reduced and the fitting precision is higher.
在曲线拟合过程中,由于数据采样率与被测信号频率之间的关系未知,以及信号的频率波动,会造成较大的误差。本文提出了一种频率精确估计正弦曲线拟合算法来解决这一问题。首先,采用椭圆拟合算法对被测信号频率进行估计;在此基础上,将基于最小二乘法的三参数正弦曲线拟合计算应用于采样数据,提高了正弦曲线拟合结果的精度。实验结果表明,本文提出的算法可以避免由于采样频率之间的关系未知而引起的频率波动和误差问题。而且经过频率估计后的拟合具有很好的随机性,拟合结果与信号幅度无关。与无频率精确估计相比,拟合误差大大减小,拟合精度更高。
{"title":"Algorithm for sine wave cure fit based on frequency precise estimation","authors":"Xuanze Wang, Yi Luo, Zhongsheng Zhai, Liangen Yang, Tao He","doi":"10.1109/ICMSC.2017.7959501","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959501","url":null,"abstract":"In the process of curve fitting, the unknown relationship between the data sampling rate and the frequency of the measured signal as well as signal's frequency fluctuations can cause remarkable error. In this paper, a sine curve fitting algorithm with frequency precise estimation is proposed to solve this problem. Firstly, ellipse fitting algorithm is used to estimate the measured signal frequency. On the basis of this, the three-parameter sine fitting calculation based on the least squares method is applied to the sampling data, and the accuracy of the sine curve fitting result is improved. The experimental results show that the algorithm proposed in this paper can avoid the problem of frequency fluctuation and error caused by the unknown relationship between the sampling frequencies. Moreover, the fitting has a good randomness after frequency estimation, and the fitting result has nothing to do with the signal amplitude. Compared without frequency accurate estimation, the fitting error is greatly reduced and the fitting precision is higher.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121534790","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: 4
The synthesis of algorithms for parameters estimation of adaptive systems 自适应系统参数估计算法的综合
Pub Date : 2017-05-01 DOI: 10.1109/ICMSC.2017.7959484
S. Lazarenko, I. Pugachev, A. Kostoglotov, Igor Deryabkin
The problem of current determining the parameters of the adaptive dynamic systems by minimizing the residuals of observations. The developed identification method allows to obtain the new structures of feedbacks with respect to the state variables and the parameters by constructing invariants. They allow to formalize a priori uncertainty in the parameters dynamics through the use of additional properties that are exposed at the true trajectory in accordance with the variation method, which follows from the Hamilton — Ostrogradskii principle which is the base for the dynamics of the adaptive system and the parameters. The variations properties allow to decompose the identification system into the subsystems of the parameter and status estimation. The relationship between them is determined by the equation for the sensitivity function. The constructiveness of the synthesized algorithms of identification is confirmed by the results of solution the problem of identifying the parameters of the nonlinear dynamic system regulator.
当前通过最小化观测值残差来确定自适应动态系统参数的问题。所提出的辨识方法可以通过构造不变量来获得关于状态变量和参数的新的反馈结构。它们允许通过使用根据变分法在真实轨迹上暴露的附加属性来形式化参数动力学中的先验不确定性,该变分法遵循Hamilton - Ostrogradskii原理,该原理是自适应系统和参数动力学的基础。变异特性允许将识别系统分解为参数和状态估计的子系统。它们之间的关系由灵敏度函数方程决定。非线性动态系统调节器参数辨识问题的求解结果验证了综合辨识算法的有效性。
{"title":"The synthesis of algorithms for parameters estimation of adaptive systems","authors":"S. Lazarenko, I. Pugachev, A. Kostoglotov, Igor Deryabkin","doi":"10.1109/ICMSC.2017.7959484","DOIUrl":"https://doi.org/10.1109/ICMSC.2017.7959484","url":null,"abstract":"The problem of current determining the parameters of the adaptive dynamic systems by minimizing the residuals of observations. The developed identification method allows to obtain the new structures of feedbacks with respect to the state variables and the parameters by constructing invariants. They allow to formalize a priori uncertainty in the parameters dynamics through the use of additional properties that are exposed at the true trajectory in accordance with the variation method, which follows from the Hamilton — Ostrogradskii principle which is the base for the dynamics of the adaptive system and the parameters. The variations properties allow to decompose the identification system into the subsystems of the parameter and status estimation. The relationship between them is determined by the equation for the sensitivity function. The constructiveness of the synthesized algorithms of identification is confirmed by the results of solution the problem of identifying the parameters of the nonlinear dynamic system regulator.","PeriodicalId":356055,"journal":{"name":"2017 International Conference on Mechanical, System and Control Engineering (ICMSC)","volume":"60 48","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114005828","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
期刊
2017 International Conference on Mechanical, System and Control Engineering (ICMSC)
全部 Acc. Chem. Res. ACS Applied Bio Materials ACS Appl. Electron. Mater. ACS Appl. Energy Mater. ACS Appl. Mater. Interfaces ACS Appl. Nano Mater. ACS Appl. Polym. Mater. ACS BIOMATER-SCI ENG ACS Catal. ACS Cent. Sci. ACS Chem. Biol. ACS Chemical Health & Safety ACS Chem. Neurosci. ACS Comb. Sci. ACS Earth Space Chem. ACS Energy Lett. ACS Infect. Dis. ACS Macro Lett. ACS Mater. Lett. ACS Med. Chem. Lett. ACS Nano ACS Omega ACS Photonics ACS Sens. ACS Sustainable Chem. Eng. ACS Synth. Biol. Anal. Chem. BIOCHEMISTRY-US Bioconjugate Chem. BIOMACROMOLECULES Chem. Res. Toxicol. Chem. Rev. Chem. Mater. CRYST GROWTH DES ENERG FUEL Environ. Sci. Technol. Environ. Sci. Technol. Lett. Eur. J. Inorg. Chem. IND ENG CHEM RES Inorg. Chem. J. Agric. Food. Chem. J. Chem. Eng. Data J. Chem. Educ. J. Chem. Inf. Model. J. Chem. Theory Comput. J. Med. Chem. J. Nat. Prod. J PROTEOME RES J. Am. Chem. Soc. LANGMUIR MACROMOLECULES Mol. Pharmaceutics Nano Lett. Org. Lett. ORG PROCESS RES DEV ORGANOMETALLICS J. Org. Chem. J. Phys. Chem. J. Phys. Chem. A J. Phys. Chem. B J. Phys. Chem. C J. Phys. Chem. Lett. Analyst Anal. Methods Biomater. Sci. Catal. Sci. Technol. Chem. Commun. Chem. Soc. Rev. CHEM EDUC RES PRACT CRYSTENGCOMM Dalton Trans. Energy Environ. Sci. ENVIRON SCI-NANO ENVIRON SCI-PROC IMP ENVIRON SCI-WAT RES Faraday Discuss. Food Funct. Green Chem. Inorg. Chem. Front. Integr. Biol. J. Anal. At. Spectrom. J. Mater. Chem. A J. Mater. Chem. B J. Mater. Chem. C Lab Chip Mater. Chem. Front. Mater. Horiz. MEDCHEMCOMM Metallomics Mol. Biosyst. Mol. Syst. Des. Eng. Nanoscale Nanoscale Horiz. Nat. Prod. Rep. New J. Chem. Org. Biomol. Chem. Org. Chem. Front. PHOTOCH PHOTOBIO SCI PCCP Polym. Chem.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1