Robust Consensus for Networked Mechanical Systems with Coupling Time Delay

Haibo Min,Shicheng Wang,Fuchun Sun,Jinsheng Zhang 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.2

This paper studies the state consensus for a class of networked nonlinear mechanical systems with coupling time delay. In particular, robust consensus protocols for both deterministic and uncertain systems with time delay are investigated. For deterministic systems, we develop a P-like protocol which allows for variable coupling time delay. We show that it is sufficient to have only the relative position information together with a damping control term, whereas the relative velocity information is not needed for state consensus. Then, an adaptive robust control protocol is proposed for uncertain sys-tems with unknown parameters in the system dynamics and arbitrary constant coupling time delays. By introducing the passivity-based framework, we demonstrate that state consensus is still reachable in this case. Finally, a numerical example is included to illustrate the obtained results.

Effective hydrogen gas sensor based on NiO@rGO nanocomposite

Ren, Haibo,Gu, Cuiping,Joo, Sang Woo,Zhao, Jingjuan,Sun, Yufeng,Huang, Jiarui Elsevier 2018 Sensors and actuators. B Chemical Vol.266 No.-

<P><B>Abstract</B></P> <P>A NiO@rGO nanocomposite is prepared by a freeze-drying method combined with heat treatment. The morphology and structure are analyzed through X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectra, and X-ray photoelectron spectroscopy. The results clearly show that NiO nanoparticles are uniformly anchored on the surface of the rGO nanosheet. The gas-sensing performance of the nanocomposite is also investigated to detect hydrogen. The NiO@rGO sensor exhibits good gas-sensing performance with high sensitivity, fast response, good reversibility, and selectivity toward hydrogen. The relative response of the sensor to 1% hydrogen is 0.64, the response time is 28 s, and the recovery time is 142 s. The improved sensing performance is due to the effective electron transfer between the NiO nanoparticles and rGO nanosheet.</P> <P><B>Highlights</B></P> <P> <UL> <LI> NiO@rGO nanocomposite consisting of NiO NPs uniformly anchored on rGO is developed. </LI> <LI> The preparation method involves freeze-drying followed by heat treatment. </LI> <LI> NiO@rGO sensor shows high response and selectivity to H<SUB>2</SUB> at low working temperature. </LI> <LI> High performance is ascribed to the electron transfer between NiO NPs and rGO. </LI> </UL> </P>

Research on the Law of Stress Development Along Backfi lling Process Between Crest and Valley of Buried Corrugated Steel Pipe Culverts

Baodong Liu,Haibo Sun,Weibo Xu,Yafei Shi,Beichen Zhang,Mengmeng Yao 한국강구조학회 2021 International Journal of Steel Structures Vol.21 No.1

Although buried corrugated steel pipe culverts have been studied intensively in the past decades, the stress development law between crest and valley during backfi lling process is still not analyzed suffi ciently, which is an important technical diffi culty for the construction of this kind of structures. In this paper, a three-dimensional fi nite element model (FEM) is developed to simulate the behavior of buried pipes during construction and the stress development law within a wavelength (curvature of corrugated pipe) ranging at the crown and the spring-line inside the pipe is proposed. Based on the measured stress data of a porous continuous corrugated steel plate pipe-arch culvert, the proposed three-dimensional FEM and stress development law are verifi ed. The results show that the stress variations in a wavelength range of corrugated steel plate are trigonometric curves. With the increase of the backfi lling height, the ratio of the stress at the crest or valley, to that of the spring-line is reduced, while the axial force is increased. The absolute value of the bending moment decays and the pipe culvert tends to be ring compression as the backfi lling height increased. The study verifi es the "ring compression theory" and the necessity of the minimum burial depth in design. Meanwhile, some design and construction guidelines which is necessary for the structure safety during backfi lling process are provided for buried corrugated steel pipe culverts.

Experimental Study on Flexural Behavior of Strengthened Corrugated Steel Plate

Baodong Liu,Fang Li,Haibo Sun,Zhihong Wang 한국강구조학회 2022 International Journal of Steel Structures Vol.22 No.1

Experimental study was conducted to verify the fl exural strength of corrugated steel plate (CSP) for various types of reinforcement which include without stiff ening ribs, with diff erent thicknesses of additional steel ribs, and with steel ribs fi lled with concrete. The test results showed that the fl exural strength of the strengthening structure of the additional steel plate using the same CSP as the main steel plate was more than 2 times that of the single CSP, and fl exural strength of the concrete-fi lled corrugated plates showed at least 3.3 times higher fl exural strength compared to the strength of single CSP. According to the force performance of the CSP strengthening structures, the nominal bearing capacity calculation formula was proposed. Specimens showed higher fl exural strength than the nominal fl exural capacity, indicating that the proposed formula of nominal fl exural strength can eff ectively evaluate the strength of strengthening structures. A fi nite element model was established in ABAQUS software to verify the feasibility of nonlinear fi nite element method analysis on CSP strengthening structures and the parameter analysis was carried out. The simulation results showed that the reinforcement ratio had a great infl uence on the bearing capacity of the strengthening structure, and the bolt spacing was second. the compressive strength of concrete was not a signifi cant improvement eff ect of the bearing capacity of concrete-encased corrugated stiff ener structure, and the strength of concrete can be negligible. The optimization suggestions were proposed for the strengthening structure concerning other factors such as bolt spacing and strengthening ratio.

Effects of Sm Content on Thermal Stability of Sm2Co17 Sintered Magnets

Minggang Zhu,Wei Sun,Haibo Feng,Yanfeng Li,Yikun Fang,Dong Zhou,Wei Li 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

Influence of Sm content on thermal stability of Sm2Co17 sintered magnets has been investigated. It is found that the temperature coefficients of remanence (α) first decrease, runs through a minimum,then starts to increases with increasing Sm content. During the sintering process, liquidphase (SmCo1.7) is beneficial to densification of the magnets. A substitution of Co for Fe in Sm-Cosintered magnets has been proved to decrease the α and improve the thermal stability of thesematerials.

Effect of nano MMT and mesoporous MCM-41 on corrosion resistance of poly (propylene carbonate) - based waterborne polyurethane

Jiaying Zhang,Hui Zheng,Haibo Geng,Ying Li,Yapeng Guan,Yuanbin Sun,Cunjian Zhu 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.4

Environmental friendly poly (propylene carbonate)-based waterborne polyurethane (PPC-based WPU) isprepared with PPC and isophorone diisocyanate (IPDI) as the soft segment and the hard segment, respectively. In thisreaction system, 2,2-dimethylolbutyric acid (DMBA) is used as the hydrophilic donor and trimethylolpropane (TMP)as the crosslinking agent. The effect of co-doping of layered montmorillonite (MMT) and mesoporous material MCM-41 on corrosion resistance of PPC-based WPU resin was studied. The properties of the samples were characterizedwith N2 physical adsorption, XRD, FT-IR, TG-DTA, DSC and water absorption testing. Potentiodynamic polarizationcurves, electrochemical impedance spectroscopy (EIS) and salt spray test were employed to investigate the corrosionperformance of all the coatings. The results of XRD indicate that the MMT in the composite polyurethane resin ispeeled off and MCM-41 maintains the hexagonal framework structure after grinding. Compared with the WPU coatingswith MMT or MCM-41 single incorporation, those with MMT and MCM-41 co-incorporation show the best corrosionresistance, which is due to the different interface structure between filler and resin matrix.

Research on Optimal Control Method for Turbofan Engine Acceleration Process with Variable Air Bleed Considering High Pressure Turbine Guide Vane Life

Changpeng Cai,Qiangang Zheng,Yong Wang,Haibo Zhang,Fengyong Sun 한국항공우주학회 2023 International Journal of Aeronautical and Space Sc Vol.24 No.2

The acceleration performance of aero-engine is an important guarantee to realize the rapid maneuvering of aircraft. The sharp change of inlet temperature of turbine caused by acceleration process poses a great challenge to the service life of high pressure turbine guide vane, and then influences engine life. How to reach a compromise between the acceleration performance and service life is one of the troublesome issues in the design and research of aero-engine control system. To handle this problem, this paper proposes an engine acceleration control method with variable outlet bleed of compressor considering the life of high pressure turbine guide vane. SQP algorithm is adopted to take into account the mechanical thermal fatigue life of turbine guide and the shortest acceleration time as the optimization objectives. In the acceleration process, the outlet bleed of compressor is adjusted to shorten the acceleration time. The simulation results demonstrate that compared with the conventional acceleration control method, the variable bleed acceleration control can decrease the acceleration time by 10%. While considering the service life of high pressure turbine guide vane, on the premise of the same acceleration time as the conventional method, the temperature gradient of high pressure turbine guide vane is reduced by 50%, the number of safe life cycles increase by 24%, and the service life of high pressure turbine guide vane is effectively enhanced.

Robust Decentralized Fault Estimation for Loss of Actuator Effectiveness of Multi-motor Web-winding System

Xiaoyan Chu,Xiaohong Nian,Miaoping Sun,Haibo Wang,Hongyun Xiong 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.3

This paper develops a method estimating the actuator power loss faults for the multi-motor web-windingsystem. Firstly, the web-winding system is regarded as a synthetic system with several dynamic subsystems andtheir dynamic models are given. Then, the nonlinear coordinate transformation is introduced to obtain a transformedsystem with block triangular structure and the interconnections among subsystems are allowed. Next, a decentralizedadaptive high-gain observer with sliding-mode is designed for the obtained transformed system to estimate thesystem actuator power loss faults. Meanwhile, the estimation error dynamics can be obtained. Sufficient conditionsof asymptotic stability for estimation error system are derived by Lyapunov theory, and the sliding-mode gain andfault estimation law are achieved. After that, the fault estimation observer for original multi-motor web-windingsystem is designed by inverse coordinate transformation. Finally, the simulations and analysis are implemented onthe three-motor web-winding system to verify the effectiveness of the proposed method.

Optimization of Mix Proportion of Self-compacting Concrete Based on Single Fluid Model

Xiuzhi Zhang,Chong Zhang,Mengdi Bi,Haibo Yang,Hailong Sun,Ru Mu 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.3

The study aims to optimize the mix proportion of self-compacting concrete according to the workability and compressive strength. Firstly, based on computational fluid dynamics, the flowability and filling ability of self-compacting concrete were simulated by the single-fluid model to verify the single-fluid model. And then, the simulation of casting a pre-cambered composite beam was carried out. In the end, the mix proportion was optimized considering the filling ability and the compressive strength of self-compacting concrete. The results showed that increasing sand rate can improve the workability and decrease the rheological parameters of self-compacting concrete. The mixture with a 45% sand ratio in the case of 3% silica fume alone or 43% sand ratio in the case of 30% granulated blast furnace slag and 3% silica fume had adequate filling ability and excellent long term compressive strength. Moreover, the model can be used to simulate the filling ability and passing capacity of self-compacting concrete and the maximum error between the simulation results and the actual measured value is 4.80%. When the concrete mixture is considered to be uniform, namely, without considering the effect of the aggregates, the single-fluid model can simulate the casting of self-compacting concrete.

Incomplete Cholesky Decomposition based Kernel Cross Modal Factor Analysis for Audiovisual Continuous Dimensional Emotion Recognition

( Xia Li ),( Guanming Lu ),( Jingjie Yan ),( Haibo Li ),( Zhengyan Zhang ),( Ning Sun ),( Shipeng Xie ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.2

Recently, continuous dimensional emotion recognition from audiovisual clues has attracted increasing attention in both theory and in practice. The large amount of data involved in the recognition processing decreases the efficiency of most bimodal information fusion algorithms. A novel algorithm, namely the incomplete Cholesky decomposition based kernel cross factor analysis (ICDKCFA), is presented and employed for continuous dimensional audiovisual emotion recognition, in this paper. After the ICDKCFA feature transformation, two basic fusion strategies, namely feature-level fusion and decision-level fusion, are explored to combine the transformed visual and audio features for emotion recognition. Finally, extensive experiments are conducted to evaluate the ICDKCFA approach on the AVEC 2016 Multimodal Affect Recognition Sub-Challenge dataset. The experimental results show that the ICDKCFA method has a higher speed than the original kernel cross factor analysis with the comparable performance. Moreover, the ICDKCFA method achieves a better performance than other common information fusion methods, such as the Canonical correlation analysis, kernel canonical correlation analysis and cross-modal factor analysis based fusion methods.