Dynamic Event-triggered Adaptive Control for Uncertain Nonlinear Switched Systems Based on MDADT Method

Xueliang Wang,Jianwei Xia,Na Zhang,Miao Yu,Xiaoxiao Guo 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.1

This article deals with the dynamic event-triggered tracking control problem for nonlinear switched systems with uncertain nonlinearities. By combining neural network control technology, mode-dependent average dwell time (MDADT) switching rule and dynamic event-triggered strategy, a valid adaptive control scheme is established, which guarantees the boundedness of all signals in the resulting closed-loop system and the tracking error eventually converges to a small neighborhood of the origin under a class of switching signals with MDADT property. Unlike the existing tracking control schemes, the proposed dynamic event-triggered strategy reduce some unnecessary transmissions from controller to actuator and thus saving network resources better. Finally, the effectiveness of the proposed control design is verified by a numerical simulation.

Bending performance of NSTS members based on steel tube connection

Xueliang Zhang,Lianguang Wang,Bailing Chen,Yaosheng Zhang 국제구조공학회 2021 Steel and Composite Structures, An International J Vol.41 No.1

This paper proposes a NSTS (new steel tube slab) structure by connecting the longitudinal steel tubes with small steel tubes in transverse, in order to decrease the construction difficulty and improve the bearing capacity of existing NTR (new tubular roof) or STS (steel tube slab) structures. Experimental study on the bending performance and influences of following parameters are carried out: the connection type of the steel tube, the diameter and eccentricity of the small steel tube, and the thickness of the bottom steel plate. The results show that the NSTS members present progressive ductile flexural failure under concentrated load. The connection type has important effect on the mechanical behavior, and the bolts fixed T-shaped plate (B+T) connection method, which provides much higher bending stiffness, is proved to be the most reliable connection type. The increase of small steel tube diameter enhances the bending performance as expected, which also confirms the effectiveness of the B+T connection, while the tube eccentricity presents little impact on the bearing capacity. The bottom steel plate significantly improves the bearing capacity and stiffness and reduces the mid-span deflection. Furthermore, the bending capacity calculation method is proposed and the calculated values show good agreement with the test results. Also, the effect rules of the diameter-thickness ratio of the small tube, the length-diameter ratio of the member and the thickness variety of the bottom steel plate on the bending capacity of NSTS members are further investigated based on the proposed theoretical method.

Comments on the stability of the synchronous states of three vibrators in a vibrating system with two rigid frames

Xueliang Zhang,Zhihui Wang,Chao Li,Jinlin Xu 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.10

This paper focuses on the stability of three homodromy vibrators in a vibrating system with two rigid frames (RFs). The motion differential equations of the system are established. Using the average method yields the average coupling torque balanced equations of three vibrators, and the simplified analytical expressions for synchronization and stability criterions of the system were derived. The coupling dynamic characteristics were numerically analyzed, including frequency-amplitude response, stable phase differences, synchronization and stability ability, and phase relationships. The simulations to verify the validity of theoretical results were carried out. It is shown that the stable states of the system are classified into three types, thereof the stability of phase differences among vibrators is similar in sub-resonant and super-resonant states, which results in no vibration of the system. While in near sub-resonant state the system reflects strong useful positive superposition vibration with energy saving, which is exactly the desire in engineering design.

Influence of Restricted Grazing Time Systems on Productive Performance and Fatty Acid Composition of Longissimus dorsi in Growing Lambs

Wang, Zhenzhen,Chen, Yong,Luo, Hailing,Liu, Xueliang,Liu, Kun Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.8

Fifty 3-month-old male Tan lambs (similar in body weight) were divided into 5 groups to investigate the effects of different restricted pasture grazing times and indoor supplementation on the productive performances and fatty acid composition of the intramuscular fat in growing lambs. The lambs grazed for different periods of time (12 h/d, 8 h/d, 4 h/d, 2 h/d, and 0 h) and received various amounts of supplementary feedings during the 120-day trial. Pasture dry matter intake (DMI), total DMI, average daily gains and the live body weights of the lambs were measured during the experiment. The animals were slaughtered at the end of the study, their carcass traits were measured, and their longissimus dorsi muscles were sampled to analyze the intramuscular fat (IMF) content and fatty acid profiles. The results indicated that the different durations of grazing and supplementary feedings affected the animal performances and the composition of fatty acids. Grazing for 8 h/d or 2 h/d with the corresponding supplementary concentrate resulted in lambs with higher body weights, carcass weights and IMF contents. Lambs with longer grazing times and less concentrate accumulated more healthy fatty acids such as conjugated linoleic acid and n-3 polyunsaturated fatty acid and had higher n-3/n-6 ratios. Overall, a grazing allowance of 8 h/d and the corresponding concentrate was recommended to maintain a high quantity and quality of lamb meat.

Fabrication of a Novel Water Swellable Styrene-butadiene Rubber through the In-situ Polymerization of Lithium Acrylate

Xueliang Jiang,Xiong Xu,Tongchuan Geng,Feng You,Wei Wang,Chu Yao 한국고분자학회 2016 폴리머 Vol.40 No.5

A novel water-swellable rubber (WSR) was prepared by blending styrene butadiene rubber (SBR) with dicumyl peroxide (DCP) and unsaturated carboxylic acid salt lithium acrylate (LiAA). The mechanical properties and water absorption behavior of WSR were studied. The results showed that LiAA was developed into polylithiumacrylate (PliAA) during the process of SBR vulcanization through in-situ polymerization, leading to the improvement of the mechanical properties and water absorption performance. The optimum usages of DCP and triallyl isocyanurate (TAIC) to attain the highest water swelling ratio for WSR were 3 and 1 phr, respectively. In addition, the tensile strength and the hardness of WSR were also enhanced by incorporating DCP or TAIC.

Optimized junction temperature fluctuation suppression technique for SiC MOSFETs in a wireless charging system

Ruoyin Wang,Xueliang Huang,Jiacheng Li 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.5

The problem of SiC MOSFET junction temperature fluctuation in wireless charging systems must be addressed immediately. The existing temperature fluctuation suppression technique requires a large number of additional switches and capacitors. This study further optimizes the temperature fluctuation tracking suppression (TFTS) strategy. This method realizes closedloop temperature adjustment and greatly simplifies the system structure. In addition, an optimized TFTS (OTFTS) strategy combined with an optimized proportional–integral–derivative control method is proposed to solve integral saturation and the subsequent control instability phenomenon. Then, a 5.5 kW experimental system is built. Results show that the OTFTS strategy eliminates 17.9 °C junction temperature fluctuation on the basis of reducing the hardware cost. It also has a good dynamic response and junction temperature fluctuation suppression effect.

Influence of Restricted Grazing Time Systems on Productive Performance and Fatty Acid Composition of Longissimus dorsi in Growing Lambs

Zhenzhen Wang,Yong Chen,Hailing Luo,Xueliang Liu,Kun Liu 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.8

Fifty 3-month-old male Tan lambs (similar in body weight) were divided into 5 groups to investigate the effects of different restricted pasture grazing times and indoor supplementation on the productive performances and fatty acid composition of the intramuscular fat in growing lambs. The lambs grazed for different periods of time (12 h/d, 8 h/d, 4 h/d, 2 h/d, and 0 h) and received various amounts of supplementary feedings during the 120-day trial. Pasture dry matter intake (DMI), total DMI, average daily gains and the live body weights of the lambs were measured during the experiment. The animals were slaughtered at the end of the study, their carcass traits were measured, and their longissimus dorsi muscles were sampled to analyze the intramuscular fat (IMF) content and fatty acid profiles. The results indicated that the different durations of grazing and supplementary feedings affected the animal performances and the composition of fatty acids. Grazing for 8 h/d or 2 h/d with the corresponding supplementary concentrate resulted in lambs with higher body weights, carcass weights and IMF contents. Lambs with longer grazing times and less concentrate accumulated more healthy fatty acids such as conjugated linoleic acid and n-3 polyunsaturated fatty acid and had higher n-3/n-6 ratios. Overall, a grazing allowance of 8 h/d and the corresponding concentrate was recommended to maintain a high quantity and quality of lamb meat.

The relationship of Rockfall Scars Structure with Magnitude - Cumulative - Frequency

( Juanjuan Sun ),( Xueliang Wang ),( Haiyang Liu ) 대한지질공학회 2019 대한지질공학회 학술발표회논문집 Vol.2019 No.2

Rockfalls are exist universally in mountain regions, steep cliffs and rock slopes with a high risk of personal safety and severely destructive of property or infrastructures. The rock mass instability and different magnitude rockfalls frequency are closely related to the rock mass structural geometry character. With the development of three - dimension rockfall modeling algorithms and tools during the last decade, we could see more about bedrock failure mechanisms and rockfall frequency under the control of rockfall scars geometry. Based the three-dimensional real scene model data of UAV point cloud, block size, volumetric joint count, joints spacing and average length of joints are carried out with statistical analysis. In this paper, we discuss cumulative frequency relation of the block size, volumetric joint count, and joints spacing, found that the block size and the volumetric joint count are follow power law distribution, with the exponent b adjusted in the range of 0.5~0.9 and 0.4~0.6, respectively. We establish the relationship of rockfall scars structure with rockfall frequency, assess its suitability. The relation can be used as a preliminary method to estimate the rockfall frequency.

Pervaporation properties of polyvinyl alcohol/ceramic composite membrane for separation of ethyl acetate/ethanol/water ternary mixtures

Shanshan Xia,Wanqin Jin,Wang Wei,Gongping Liu,Xueliang Dong 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.2

In further purification of ethyl acetate (EAC) process, azeotropic distillation or extractive distillation is usually applied. High energy consumption limits the economic profit of the process. In this study, pervaporation separation of EAC/ethanol (EA)/water ternary mixtures using the ceramic-supported polyvinyl alcohol (PVA) composite membrane was investigated to substitute the azeotropic distillation or extractive distillation. Swelling experiments were performed to evaluate the sorption characteristic of the membrane. Flory-Huggins theory was applied to study the interaction between the membrane and the penetrant. The UNIFAC model was adopted to investigate the variation of the penetrant activity in the membrane. The effects of operation temperature, feed water content and feed flow rate on the PV performance of the membrane were systematically investigated. The composite membrane exhibited high PV performance with the total flux of 2.1 kg·m−2·h−1 and 94.9 wt% permeate concentration of water (operation condition:feed composition 82.6 wt% EAC, 8.4 wt% EA, 9 wt% water, feed temperature 60 oC, feed flow rate 252 mL·min−1). The PV performance of the membrane varied slightly over a continuous PV experiment period of 110 h. Our results demonstrated that the PVA/ceramic membrane was a potential candidate for the purification of EAC/EA/water ternary mixtures.

Design and optimization of novel transceiver device for one‑way single‑wire power transfer

Yang Li,Taocheng Hu,Xueliang Wang,Yujie Zhai,Yao Li,Wenxin Huang,Zhigang Lou 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.10

The further development of wireless power transfer technology is hindered by the limiting relationship between transmission distance, transmission efficiency, and size of the coupling mechanism. Thus, a feasible solution was provided by one-way single-wire power transfer. First, a horn-type mode conversion device was proposed in this study by analyzing the principle of one-way single-wire power transfer. Second, the system structure was designed to save materials and reduce the volume of space. The transmission efficiency of the system was improved, and the operating frequency was reduced by optimizing the parameters of the mode conversion device. Finally, the feasibility and structural applicability of the one-way single-wire power transfer method proposed in this study were proved by the experimental results.