Resource Type

Journal Article 7

Year

2022 2

2017 1

2010 1

2008 1

2002 1

Keywords

rectification 2

12-phase rectification 1

Activity analysis 1

Adaptive robust control 1

Automatic systems 1

Construction workers 1

Object tracking 1

Parallel mechanism 1

Parameter initialization 1

Pneumatic cylinders 1

Pose estimation 1

additional position change 1

composite tube 1

deviation correction trajectory 1

diffuser/nozzle Si/Glass 1

diffuser/nozzle micropump 1

double-winding AC - DC generator 1

earth pressure balance shield 1

electric power integration 1

energy efficiency 1

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Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

Frontiers of Mechanical Engineering 2022, Volume 17, Issue 2, doi: 10.1007/s11465-022-0676-4

Abstract: The control system presently used in shield posture rectification is based on driver experience, whichTherefore, a decision-making approach for the deviation correction trajectory and posture rectificationThe posture rectification loads and shield behaviors results can be solved by the proposed method.., bedrock height in the upper-soft and lower-hard strata) on shield behaviors and posture rectificationThe bedrock height increases the magnitudes of the required posture rectification moments when h

Keywords： position change     deviation correction trajectory     earth pressure balance shield     mechanical model     posturerectification    

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A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy

Frontiers of Mechanical Engineering 2022, Volume 17, Issue 3, doi: 10.1007/s11465-022-0685-3

Abstract: integrated into a piezo-driven chamber, and a novel valveless piezoelectric pump with the function of rectificationEventually, experiments were designed, and results showed that NVPPFR had the function of rectification

Keywords： composite tube     valveless piezoelectric pump     rectification     energy efficiency    

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Construction Activity Analysis of Workers Based on Human Posture Estimation Information

Xuhong Zhou,Shuai Li,Jiepeng Liu,Zhou Wu,Yohchia Frank Chen,

Engineering doi: 10.1016/j.eng.2023.10.004

Abstract: Identifying workers’ construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress. However, current activity analysis methods for construction workers rely solely on manual observations and recordings, which consumes considerable time and has high labor costs. Researchers have focused on monitoring on-site construction activities of workers. However, when multiple workers are working together, current research cannot accurately and automatically identify the construction activity. This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers. In this framework, multiple deep neural network models are designed and used to complete worker key point extraction, worker tracking, and worker construction activity analysis. The designed framework was tested at an actual construction site, and activity recognition for multiple workers was performed, indicating the feasibility of the framework for the automated monitoring of work efficiency.

Keywords： Pose estimation     Activity analysis     Object tracking     Construction workers     Automatic systems    

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Piezoelectric diffuser/nozzle micropump with double pump chambers

WANG Wei, ZHANG Ying, TIAN Li, CHEN Xiaojie, LIU Xiaowei

Frontiers of Mechanical Engineering 2008, Volume 3, Issue 4,   Pages 449-453 doi: 10.1007/s11465-008-0076-4

Abstract: To eliminate check valve fatigue and valve clogging, diffuser/nozzle elements are used for flow rectification

Keywords： diffuser/nozzle Si/Glass     phenomenon     rectification     diffuser/nozzle micropump     frequency    

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AC-DC Power Integration Techniques

Ma Weiming

Strategic Study of CAE 2002, Volume 4, Issue 12,   Pages 53-59

Abstract:

A novel AC — DC machine is invented on the basis of the proposed new idea of electric power integration, wherein the stator with one set of 3-phase AC winding and another set of 12-phase DC winding, together with a rotor having a d-axis field winding and a q-axis stabilizing winding, is combined with a 12-phase bridge rectifier, an AC exciter with an excitation system, the automatic voltage regulator as well as a cooling system to form an integral whole. Simultaneous AC and DC power supplies with high quality being available, this new generator is especially suitable for self-contained electrical systems, such as those found on aircraft and ships, where good performance and compact size are essential. Mathematical models of the machine are established and calculation and measurement methods of the model parameters are proposed, providing a theoretical basis for solving the key technical problems. Low-frequency oscillations occurring in a synchronous generator-rectifier system are examined, stability criterion of the system is obtained, and technical measures are proposed to ensure system’s stable operation. With the AC voltage regulated, the DC voltage floats within an acceptable range, which can be achieved through rational machine design. Due to complete electrical separation of the AC and DC circuits and usage of the properly designed 12-phase DC winding, the AC voltage distortion caused by DC commutation and the DC voltage pulsation are greatly reduced, which considerably improves the EMC of the system. Expressions for the peak current and impact torque following a short-circuit fault at DC side or at both AC and DC sides are derived once the strong nonlinearity of the system is ingeniously handled. The principle and methods for on-line real time fault diagnosis of the diodes in the 12-phase rectifier are proposed so that the state of each diode can be easily judged according to the input/output-voltage waveforms. Based on the achievements of above research, AC - DC generators with high performance have been developed, laying the foundation for integration of self-contained electrical systems.

Keywords： electric power integration     double-winding AC - DC generator     12-phase rectification     simultaneous AC and    

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Research on large slurry shield excavation parameter control under complex conditions

Wang Baiquan,Ren Yong,Jin Zhongxiang,Gu Yanqi

Strategic Study of CAE 2010, Volume 12, Issue 12,   Pages 65-69

Abstract: Some measures for shield posture control and a brief introduction on synchronized grouting parameters

Keywords： slurry shield     excavation parameter     synchronized grouting     slurry cycling     shield posture    

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Posture control of a 3-RPS pneumatic parallel platform with parameter initialization and an adaptive Article

Guo-liang TAO,Ce SHANG,De-yuan MENG,Chao-chao ZHOU

Frontiers of Information Technology & Electronic Engineering 2017, Volume 18, Issue 3,   Pages 303-316 doi: 10.1631/FITEE.1500353

Abstract: A control algorithm for a 3-RPS parallel platform driven by pneumatic cylinders is discussed. All cylinders are controlled by proportional directional valves while the kinematic and dynamic properties of the system are modeled. The method of adaptive robust control is applied to the controller using a back-stepping approach and online parameter estimation. To compensate for the uncertainty and the influence caused by estimations, a fast dynamic compensator is integrated in the controller design. To prevent any influence caused by the load applied to the moving platform changing in a practical working situation, the identification of parameters is taken as the initialization of unknown parameters in the controller, which can improve the adaptability of the algorithm. Using these methods, the response rate of the parameter estimation and control performance were improved significantly. The adverse effects of load and restriction forces were eliminated by the initialization and online estimation. Experiments under different situations illustrated the effectiveness of the adaptive robust controller with parameter initialization, approaching average tracking errors of less than 1%.

Keywords： Parameter initialization     Adaptive robust control     Parallel mechanism     Pneumatic cylinders    

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Title Author Date Type Operation

Deviation correction strategy for the earth pressure balance shield based on shield–soil interactions

Journal Article

A valveless piezoelectric pump with novel flow path design of function of rectification to improve energy

Journal Article

Construction Activity Analysis of Workers Based on Human Posture Estimation Information

Xuhong Zhou,Shuai Li,Jiepeng Liu,Zhou Wu,Yohchia Frank Chen,

Journal Article

Piezoelectric diffuser/nozzle micropump with double pump chambers

WANG Wei, ZHANG Ying, TIAN Li, CHEN Xiaojie, LIU Xiaowei

Journal Article

AC-DC Power Integration Techniques

Ma Weiming

Journal Article

Research on large slurry shield excavation parameter control under complex conditions

Wang Baiquan,Ren Yong,Jin Zhongxiang,Gu Yanqi

Journal Article

Posture control of a 3-RPS pneumatic parallel platform with parameter initialization and an adaptive

Guo-liang TAO,Ce SHANG,De-yuan MENG,Chao-chao ZHOU

Journal Article