Stability and Static Output Feedback Stabilization for a Class of Nonlinear Discrete-Time Singular Switched Systems

Wei Wang,Wei Wang,Chenghui Zhang 제어·로봇·시스템학회 2013 International Journal of Control, Automation, and Vol.11 No.6

In this paper, the stability and static output feedback stabilization problems for a class of nonlinear discrete-time singular switched systems are discussed. First, based on Lyapunov theory and the implicit function theorem, linear matrix inequalities sufficient conditions are developed which guarantee that the nonlinear discrete-time singular switched systems are regular, causal, have unique solution in a neighborhood of the origin, and are uniformly asymptotically stable. Then, with these conditions, and based on singular value decomposition approach, the design method of static output feedback controllers is given. Last, numerical examples are provided to illustrate the effectiveness of the proposed methods.

Facile synthesis of polyethyleneimine@Fe3O4 loaded with zirconium for enhanced phosphate adsorption: Performance and adsorption mechanism

Chenghui Ma,Xiaoting Zhang,Xiaoting Zhang,Kang Wen,Rong Wang,Runping Han 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.1

Coating superparamagnetic iron oxide particles, i.e., Fe3O4, as adsorbents have major advantages over bare adsorbents for water treatment. As a versatile material, zirconium has been extensively studied for phosphate removal. In this study, the Fe3O4 core was pre-coated with branched polyethyleneimine (PEI) first, and then loaded with zirconium to result in a highly selective adsorbent (i.e., Zr-PEI@Fe3O4) for phosphate with a greatly broadened pH range. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), BET surface area, and magnetization were used to characterize the resulting adsorbent and to explore the underlying adsorption mechanism. The adsorption performance of Zr-PEI@Fe3O4 toward phosphate was performed by batch experiment. The results showed that Freundlich model better fit the adsorption isotherms, while the Elovich equation better described the kinetic process. The maximum adsorption capacity of dephosphorization 32.2mg·g1 (according to P element) emerged in the condition of 1.0 g·L1 and pH at 2 with 303 K. The process was spontaneous and endothermic. Zr-PEI@Fe3O4 has the potential to remove phosphate from solution due to its easy separation and some good adsorption property.

Investigation on the adsorption performance of modified coal gangues to p-hydroxybenzenesulfonic acid

Peng Longgui,Wang Rong,Cheng Huanquan,Zhang Liangqing,He Yugang,Yin Chenghui,Zhang Xin 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.7

Coal gangue (CG) has dense structure and excellent internal crystallization. After modification, its pore structure can be enlarged and become an adsorptive material with good adsorption performance, which is a good idea to recover solid waste of CG to a certain extent. At the same time, the content of organic matter in the wastewater of medical intermediate is high. Modified CG can be used as an ideal material for the adsorption treatment of medical intermediate wastewater. Herein, the CG was treated with three activation methods of high-temperature calcination, freezing microwave and acidification treatment to investigate their adsorption behavior to p-hydroxybenzenesulfonic acid. SEM, FTIR, XRD, XPS and BET were used to study the microstructure of raw and modified CG. The relationship between the activation methods and the structure of the CGs was established. The specific surface area of calcined CG increases obviously, which is attributed to the elimination of interlayer water. Acidification treatment can effectively activate the chemical structure of CG surface. By using ultraviolet spectrophotometer, both the kinetics and thermodynamics of the adsorption processes are investigated and fitted with the kinetic equations and adsorption thermodynamic equations. Results indicate that the CG treated with acidification method has the best adsorption effect on p-hydroxybenzenesulfonic acid, and the maximum removal rate reaches 85.34%. The quasi-second-order rate equation and Freundlich model are adopted to analyze the adsorption kinetics and thermodynamics, and results show that the adsorption process includes both physical adsorption and chemisorption. Overall, the relationships of activation method-microstructure-adsorption performance are revealed, which is significant to guide the application of CG in the adsorption field.

Quality changes of two sweet cherry cultivars with different susceptibility to cracking during the storage

Bin Yuqi,Liu Chenghui,Xie Jiani,Wang Mingyu,Chen Chen,Jiang Aili 한국원예학회 2024 Horticulture, Environment, and Biotechnology Vol.65 No.3

This study aimed to investigate the diff erence in postharvest quality and storage tolerance of two sweet cherry cultivars with diff erent susceptibility to cracking (‘Rainier’: less-susceptible, ‘Wanhongzhu’: more-susceptible). Cracking assays confi rmed that ‘Wanhongzhu’ was more susceptible to cracking than ‘Rainier’, with the T 50 (the half time of fruit cracking in a given solution) of 5.53 and 22.27 h, respectively. During the storage, respiration rate, soluble solids content, titratable acid content, soluble protein content, ascorbic acid content, and fi rmness of ‘Wanhongzhu’ were higher than those of ‘Rainier’, but the color change and ethylene production were lower than those of ‘Rainier’. For the expression levels of cell wall metabolism-related genes, the expressions of Paβ-Gal , PaEXA4 , PaaqpSIP2.1 , and PaaqpPIP2.4 in ‘Wanhongzhu’ were higher than those of ‘Rainier’ during the storage, however, the expressions of PaPME , PaPEL.7 , PaXTH , PaPAE.1 , PaPOD and PaExp1 were lower than those of ‘Rainier’. Correlation analysis results suggest the expressions of cell wall metabolism-related genes in ‘Wanhongzhu’ had less eff ect on fruit quality than that in ‘Rainier’. Overall, compared with ‘Rainier’, ‘Wanhongzhu’ had better fruit quality during the low-temperature storage, but it was more likely to produce fruits cracking and rot, which shortens its shelf-life. Therefore, ‘Wanhongzhu’ is more suitable for short-term storage.

Numerical simulation of infill CACB wall cracking subjected to wind loads

Ruige Li,Yu Gao,Hongjian Lin,Mingfeng Huang,Chenghui Wang,Zhongzhi Hu,Lingyi Jin 국제구조공학회 2024 Structural Engineering and Mechanics, An Int'l Jou Vol.89 No.5

The cracking mechanism in ceramsite aerated concrete block (CACB) infill walls were studied in low seismic fortification intensity coastal areas with frequent occurrence of typhoons. The inter-story drifts of an eight-story residential building under wind loads and a seismic fortification intensity of six degrees were analyzed by using the PKPM software. The maximum inter-story drift ratio of the structure in wind load was found to be comparable to that under the seismic fortification intensity of six degrees. However, when accounting for the large gust wind speed of typhoon, the maximum inter-story drift ratio was much larger than that obtained under reference wind load. In addition, the finite element models of RC frames were employed by displacement loading to simulate two scenarios with and without window hole in the CACB infill walls, respectively. The simulation results show no signs of cracking in both the infill walls with window hole and those without window for the inter-story drift caused by seismic loads and the reference wind load. However, both types of infill walls experienced structural creaking when assessing the gust wind pressure recorded from previous typhoon monitoring. It is concluded that an underestimate of wind loads may contribute substantially to the cracking of frame CACB infill walls in low seismic fortification intensity coastal areas. Consequently, it is imperative to adopt wind pressure values derived from gust wind speeds in the design of CACB infill walls within frame structures. Finally, the future research directions of avoiding cracks in CACB filled walls were proposed. They were the material performance improving and building structure optimizing.

In Situ Formation of Leaf-Like Ag2S/CdS Heterojunction Photocatalyst Harnessing Vis-NIR Light for Photodegradation of Organic Pollutants

Chang, Libin,Zhu, Gangqiang,Lu, Huan,Hojamberdiev, Mirabbos,Zhang, Zengping,Gao, Jianzhi,Wang, Chenghui,Yang, Woochul Springer-Verlag 2018 Catalysis letters Vol.148 No.9

High Plasticity of the Gut Microbiome and Muscle Metabolome of Chinese Mitten Crab (Eriocheir sinensis) in Diverse Environments

( Xiaowen Chen ),( Haihong Chen ),( Qinghua Liu ),( Kangda Ni ),( Rui Ding ),( Jun Wang ),( Chenghui Wang ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.2

Phenotypic plasticity is a rapid response mechanism that enables organisms to acclimate and survive in changing environments. The Chinese mitten crab (Eriocheir sinensis) survives and thrives in different and even introduced habitats, thereby indicating its high phenotypic plasticity. However, the underpinnings of the high plasticity of E. sinensis have not been comprehensively investigated. In this study, we conducted an integrated gut microbiome and muscle metabolome analysis on E. sinensis collected from three different environments, namely, an artificial pond, Yangcheng Lake, and Yangtze River, to uncover the mechanism of its high phenotypic plasticity. Our study presents three divergent gut microbiotas and muscle metabolic profiles that corresponded to the three environments. The composition and diversity of the core gut microbiota (Proteobacteria, Bacteroidetes, Tenericutes, and Firmicutes) varied among the different environments while the metabolites associated with amino acids, fatty acids, and terpene compounds displayed significantly different concentration levels. The results revealed that the gut microbiome community and muscle metabolome were significantly affected by the habitat environments. Our findings indicate the high phenotypic plasticity in terms of gut microbiome and muscle metabolome of E. sinensis when it faces environmental changes, which would also facilitate its acclimation and adaptation to diverse and even introduced environments.