检索结果-内蒙古大学图书馆

design of deep-water omnidirectional spirit level

Journal of Measurement Science and Instrumentation 2021年第4期12卷 472-478页

作者： ZHAO Lianyu LI Shuo ZHAO Xiaolei LI Maolin CHEN Jinyu WANG Chenglin Tianjin Key Laboratory of Advanced Mechatronic System Design and Intelligent Control National Demonstration Center of Experimental Mechanical and Electrical Engineering EducationSchool of Mechanical EngineeringTianjin University of TechnologyTianjin 300384China Offshore Oil Engineering Co. Ltd.Tianjin 300461China

Attitude adjustment is a key link in the installation process of underwater facilities in deep *** solve this problem,an omnidirectional spirit level for deep water was *** sealing principle of the spirit level and the principle of deep-water pressure resistance are analyzed,and the threaded connection strength is *** mechanical simulation verifies that the spirit level can withstand the pressure of 2000 m water depth,and the water pressure test is carried out for 30 min in a 20 MPa hyperbaric *** the experiment is completed,the appearance of the spirit level is intact and there is no *** experiment results show that the deep-water omnidirectional spirit level can be used in the deep sea within 2000 m.

关键词： deep water omnidirectional spirit level attitude adjustment pressure test underwater pressure

来源：评论

学校读者我要写书评

暂无评论

A novel lightweight optimization design of gear shaper

引用

UPB Scientific Bulletin, Series D: Mechanical Engineering 2019年第4期81卷 241-252页

作者： Zheng, Qing-Chun Lu, Kai-Jie Zhu, Pei-Hao Ma, Wen-Peng Liu, Jing Na Hu, Ya-Hui Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology China

The machine produces vibrations under the excitation of the cutting load and the non-equilibrium inertia of the actuator and actuator, which affects the machining accuracy and reduces the processing efficiency. A dynamic design method of machine tool structure is put forward and studied to ensure the dynamic properties of machine tool structure and realize the machining precision which improved machine tool weight is reduced by 18.3%, the machine natural frequency is increased by 2.1%, which improves the machine Performance, and access to the final design. © 2019, Politechnica University of Bucharest. All rights reserved.

关键词： Actuators

来源：评论

学校读者我要写书评

暂无评论

Distribution of Dislocation-Twin Interaction in Twip Steel Under Different Loading Modes

SSRN

引用

SSRN 2022年

作者： Guo, Xiangru Mao, Ningdong Sun, Chaoyang Wang, Chunhui Cui, Yinan Xiong, Zhiping Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin300384 China School of Mechanical Engineering University of Science and Technology Beijing Beijing100083 China Applied Mechanics Lab School of Aerospace Engineering Tsinghua University Beijing100084 China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of Technology Beijing100081 China

The tension-compression asymmetry and orientation effect of dislocation-twin boundary (TB) interactions in twinned TWIP steels were investigated using the discrete dislocation dynamics simulations and Schmid's law. The different types of dislocations dominate the TB migration in the twinned TWIP steel during tension and compression with the same loading orientation, and the asymmetric dislocation reactions at TB were attributed to the different leading partials produced after the dissociation of dislocation under different loading modes (tension or compression). Moreover, the complex dislocation-TB interactions, such as dislocations traversing TB, cross slip, dissociation, pile up and so on, were determined by considering the orientation effect of dislocation activation and the asymmetry of dislocation dissociation. The research advances the understanding of asymmetric behavior of twin and its influence on the macro hardening in plastic deformation of TWIP steels. © 2022, The Authors. All rights reserved.

关键词： Dissociation

来源：评论

学校读者我要写书评

暂无评论

Global Dynamics and Optimal design of a New Highly Efficient Nonlinear Energy Sink Based on Magnetic-Elastic Impacts with Negative Stiffness

Research Square

引用

Research Square 2021年

作者： Li, Shuangbao Wang, Tingting Chen, Jianen Research Institute of Science and Technology Innovation Civil Aviation University of China Tianjin300300 China College of Science Civil Aviation University of China Tianjin300300 China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China

A new highly efficient elastic-impact bistable nonlinear energy sink (EI-BNES) based on magnetic-elastic impacts with negative stiffness and bistability is proposed and optimized through global dynamical analysis. The EI-BNES has better robustness and higher energy dissipation rates with nearly more than 96.5% for broadband impulsive excitations than the traditional cubic NESs and single bistable NESs. The structure of negative stiffness impacts is realized by reasonable layout of permanent ring magnets and springs. A two-degree-of-freedom (two-DOF) elastic-impact system is established to describe the coupled nonlinear interaction between the main structure and the attached EI-BNES. A global Melnikov reduction analysis (GMRA) is proposed to study global dynamics and homoclinic bifurcations of the reduced two-dimensional subsystem, which is used to explain the mechanism of nonlinear targeted energy transfer (TET) and detect the threshold of impulsive amplitudes of EI-BNES for in-well and compound motions between in-well and cross-well resonance responses. A special type of saddle-center equilibrium points is also found in the non-smooth system of the EI-BNES and can be used to effectively increase the energy dissipation rates. The optimal design criterion of the tuned EI-BNES for better dissipation performance is also first discussed based on the GMRA and numerical techniques for calculating the Melnikov function of the non-smooth systems. The effectiveness of the analytical GMRA is also verified by numerical simulations. © 2021, CC BY.

关键词： Stiffness

来源：评论

学校读者我要写书评

暂无评论

Reform and Practice in Experimental Teaching from the View of "Emerging Engineering": Case Study on the Field of Energy and Power Engineering

Reform and Practice in Experimental Teaching from the View o...

引用

Information Communication Technologies Conference (ICTC)

作者： He Tian Lijian Liu Miao Tian Shimin Zhou Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology) School of Mechanical Engineering Tianjin University of Technology Tianjin China Tianjin Academy of Educational Science Tianjin China Tianjin Newborn New Energy Technology Co. Ltd Tianjin China

According to the idea of "Emerging Engineering Education" talent training model of Ministry of Education, students should be trained to have "metaphysical" concept, connection, imagination, macro thinking. Project-driven experiment teaching focuses on a project, and the goal is the completion of the project; the student is the center of teaching activities, which is supported by the inquiry process. This study analyzes the significance of the project-driven method in experimental teaching. This paper describes the implementation process of experimental teaching in the field of energy and power engineering in terms of project design, teaching system construction and so on under the project-driven method. By analyzing the results of a questionnaire survey distributed to students of energy and power in the College of Mechanical Engineering at the tianjin University of Technology, it is found that the students are satisfied with the effects of project-driven experimental teaching, and the use of experimental teaching has greatly aroused the students' enthusiasm for learning. The ability of the students to engage in autonomous learning, engineering practice and innovation has been greatly improved, and a good teaching effect has been achieved.

关键词： Training Power engineering Technological innovation Education Solids Communications technology Mechanical engineering

来源：评论

学校读者我要写书评

暂无评论

Compound nonlinear energy sink with multiple motion types for absorbing energy from wide excitation ranges

引用

Journal of Sound and Vibration 2025年 617卷

作者： Jianen Chen Jiaqi Zhao Wei Zhang Min Sun Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin 300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin 300384 China School of Civil Engineering and Architecture Guangxi University Nanning 530004 China School of Science Tianjin Chengjian University Tianjin 300384 China

Nonlinear energy sink (NES) has garnered significant attention since its inception due to its notable broadband vibration reduction capability. However, the introduction of strong nonlinear characteristics by NESs complicates system responses, leading to a loss of effectiveness when the excitation force exceeds a specific threshold. Consequently, NESs have limited applicability in engineering because they are effective only within a constrained range of excitation amplitude. In this study, a compound NES (CNES) with multiple motion types is designed to extend the effective force range while maintaining broadband vibration reduction capability. The CNES is distinguished by its piecewise stiffness, collision mechanisms, and unique design of two-degree-of-freedom oscillators. The wide effective range of the CNES is demonstrated through slow linear sweep and fixed-frequency tests. The results indicate that the CNES effectively reduces vibrations in the primary oscillator (PO) with various resonant frequencies. Notably, the CNES achieves significant vibration reduction over a particularly wide range of excitation amplitude when controlling the PO with relatively high resonance frequencies (approximately 10.5 Hz and 19 Hz). However, a nonnegligible limitation of the CNES is its restricted effective range of excitation amplitude when the PO resonates at lower frequency (approximately 7 Hz). Moreover, five motion types of the CNES are identified and analyzed, with one motion type autonomously emerging in response to changes in excitation parameters, ensuring excellent vibration reduction performance across a wide excitation range. Finally, the performance of the CNES and a degraded single-degree-of-freedom CNES are compared to further demonstrate the extension effect of the multiple motion types on the effective range. The CNES can be used in scenarios where the parameters of protected systems and excitations vary widely, providing a thought to improve the NESs.

关键词： Compound nonlinearity Compound features Vibration reduction Vibration test Multiple motion types Effective range

来源：评论

学校读者我要写书评

暂无评论

Transformer-LSTM-KOA: A novel approach for prediction of chlorophyll in the South China Sea

引用

Environmental Modelling & Software 2025年 192卷

作者： Gang Chen Zhenzhong Liu Runfeng Zhang Guobin Zhang Jutao Wang Tongrui Zhang Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin 300384 China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education (Tianjin University of Technology) Tianjin China School of Environmental Science and Safety Engineering Tianjin University of Technology Tianjin 300384 China Tianjin Hanhailanfan Marine Technology Co. Ltd. Tianjin 300457 China

Chlorophyll is a critical indicator of marine primary productivity and is essential in assessing aquatic ecosystem health. To address the limitations of current prediction models regarding accuracy, mobility, and reliability, this study proposes a novel Transformer-LSTM-KOA model for Chlorophyll prediction. Leveraging remote sensing data from the South China Sea, the model synergistically integrates Transformer's global analytical capabilities via self-attention and multi-head attention mechanisms with LSTM's proficiency in capturing long-term dependencies through gated mechanisms. The Kepler Optimization Algorithm (KOA) is subsequently employed to systematically optimize both global and local model parameters, thereby enhancing adaptability and robustness across diverse prediction datasets. Experimental results demonstrate superior performance with MSE and MAE values of 0.00011 and 0.00685, respectively, outperforming benchmark models. This enhanced modeling framework provides crucial technical support for marine ecological forecasting and early warning systems.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Research on Crack Detection of Nonlinear Rotor Based on Energy Tracks

Research on Crack Detection of Nonlinear Rotor Based on Ener...

引用

IEEE International Conference on Mechatronics and Automation

作者： Yu Zhang Jun Liu Zhu Han Tianjin Key Laboratory for Advanced Mechanical System Design and Intelligent Control Tianjin University of Technology Tianjin China National Demonstration Centre for Experimental Mechanical and Electrical Engineering Education Tianjin University of technology

ISBN: (数字)9781728164168

ISBN: (纸本)9781728164175

In rotating machinery, because of high-speed working characteristics and terrible working conditions with variable cycles and variable loads, it is easy for rotors to cause a crack initiation and propagation, which may cause serious harm or even the life-threatening. The super harmonic component is an important role of the crack detection. But it is difficult to reflect the super harmonic component in the high-speed region after super harmonic resonances. In this paper, the dynamic equation of a nonlinear rotor system with a crack is considered, the potential energy expression of the cracked rotor is derived, and the concept of energy tracks is proposed. In the distortion of energy tracks, the effects of different crack parameters and nonlinear parameters on the vibration characteristics of the rotor system are compared. The results show that the energy trajectory distortion can diagnose the crack fault. It provides a new research method for vibration response analyses and fault diagnoses of cracked rotor system.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Research on Asymmetrical Dual-rotor system Based on the Energy Orbit

Research on Asymmetrical Dual-rotor System Based on the Ener...

引用

IEEE International Conference on Mechatronics and Automation

作者： Zhu Han Jun Liu Yu Zhang Tianjin Key Laboratory for Advanced Mechanical System Design and Intelligent Control Tianjin University of Technology Tianjin China National Demonstration Centre for Experimental Mechanical and Electrical Engineering Education Tianjin University of technology

ISBN: (数字)9781728164168

ISBN: (纸本)9781728164175

Studying the vibration of asymmetrical dual-rotor is very important for aero engines. In this paper, based on the vibration characteristics of an aero-engine, a different novel coupled dynamic model is proposed based on the spring recovery characteristics of rotor. The model dynamic equations of asymmetrical dual-rotor are obtained by the Lagrange equation, and vibration resonance curves of high pressure and low pressure rotors are numerically simulated and theoretically analyzed by using the Runge-Kutta algorithm. The research show that the system occurs combined vibration, harmonic vibration and superharmonic vibration. In addition, the vibration occurring mechanism was investigated and verified in detail through numerical simulation. For the first time, the concept of energy orbit was introduced into the dual-rotor model system. The energy orbit represents the vibration characteristics and energy exchange process of the model system. Energy orbit is a new energy orbit method for analyzing vibration characteristics of rotor system. The new researches of this paper will show a different research direction for complex dual-rotor systems.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A SSVEP-Based Wireless Retrieval Robot system

A SSVEP-Based Wireless Retrieval Robot System

引用

Chinese Automation Congress (CAC)

作者： Sihao Yang Tao Xue Shicheng Yan Zekun Tian Yuxin Zhang Qihuai Zhang Jintao Chen Zhongli Bai Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control National Demonstration Center for Experimental Mechanical and Electrical Engineering Education Tianjin University of Technology Tianjin China Tianjin Key Laboratory for Control Theory and Applications in Complicated Systems Tianjin University of Technology Tianjin China

ISBN: (数字)9781728176871

ISBN: (纸本)9781728176888

The brain-computer interface (BCI) plays an important role in assisting the disabled in life support and entertainment. In this study, a wireless retrieval robot system for steady-state visual evoked potential (SSVEP) based BCI system was proposed. In order to improve the recognition accuracy and system stability of BCI system for subjects' instructions, in this study, offline and online experiments are used to study and solve the performance parameters, obstacle avoidance and retrieval performance of BCI respectively. In the offline experiment, 5 types of SSVEP data of 4 subjects were used. Based on CCA algorithm, the multi-channel fusion recognition accuracy, time window length (TWL), command activation margin and other aspects are studied. The optimal experimental parameters are determined. Online experiments are based on the optimal test parameters of offline experiments, 8 subjects were used to study the performance of obstacle avoidance and retrieval. The online experiments achieved an average accuracy of 87.89 ± 6.62% with an ITR of 23.6 ± 4.76 bit/min. Furthermore, the rate of success in grasping three kinds of different difficulty preset targets was 61.38%.

关键词： Electroencephalography Robots Electrodes Correlation coefficient Task analysis Visualization Liquid crystal displays

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：