Robust H∞ Control of Uncertain Nonlinear Switched Systems using Constructive Method

Ben Niu,Jun Zhao 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.3

This paper focuses on the problem of robust H∞ control of nonlinear switched systems with parameter uncertainty via the multiple Lyapunov functions (MLFs) approach. The uncertain parameters are assumed to be in a known compact set and are allowed to enter the system nonlinearly. Based on the explicit construction of Lyapunov functions, which avoids solving the Hamilton-Jacobi-Isaacs (HJI) inequalities, sufficient conditions for the solvability of the robust H∞ control problem of cascade nonlinear switched systems are derived under some switching signal. Then, the result is extended to solve the robust H∞ control problem of nonlinear switched systems in strict feedback form. Finally, the effectiveness of the proposed results is illustrated through a simulation example.

Meta-Analysis of Circulating Endothelial Cells and Circulating Endothelial Progenitor Cells as Prognostic Factors in Lung Cancer

Yu, Min,Men, Hai-Tao,Niu, Zhi-Min,Zhu, Yu-Xi,Tan, Ben-Xu,Li, Long-Hao,Jiang, Juan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

Background: The aim of this study was to analyze the prognostic implications of pretreatment circulating endothelial cells (CECs) and circulating endothelial progenitor cells (CEPCs) for the survival of patients with lung cancer. Materials and Methods: Relevant literature was identified using Medline and EMBASE. Patient clinical characteristics, overall survival (OS) and progression-free survival (PFS) together with CEC and CEPC positive rates before treatment were extracted. STATA 12.0 was used for our analysis and assessment of publication bias. Results: A total of 13 articles (8 for CEC and 5 for CEPC, n=595 and n=244) were pooled for the global meta-analysis. The odds ratio (OR) for OS predicted by pretreatment CECs was 1.641 [0.967, 2.786], while the OR for PFS was 1.168 [0.649, 2.100]. The OR for OS predicted by pretreatment CEPCs was 12.673 [5.274, 30.450], while the OR for PFS was 4.930 [0.931, 26.096]. Subgroup analyses were conducted according to clinical staging. Odds ratio (OR) showed the high level of pretreatment CECs only correlated with the OS of patients with advanced lung cancer (stage III-IV). Conclusions: High counts of CECs seem to be associated only with worse 1-year OS in patients with lung cancer, while high level of pretreatment CEPCs correlate with both worse PFS and OS.

Weight Estimation and Secure Control for Discrete Stochastic Distribution Control Systems Under Sparse Sensor Attacks

Xiaoyun Yi,Yuwei Ren,Li Qi,Ben Niu,Yixian Fang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.4

In this paper, we investigate the problem of weight estimation and secure control for discrete stochastic distribution control (SDC) systems under sparse sensor attacks. Firstly, a Luenberger observer is designed for the linear SDC systems to perform the weight estimation under sparse sensor attacks. Then, a generalized proportionalintegral (PI) tracking control strategy is proposed for the linear B-spline model. Furthermore, the tracking problem for output probability density functions (PDFs) is implemented, and the designed controller ensures that the closedloop system is stable. Finally, the simulation results show the effectiveness of the proposed method.

Effects of Black Raspberry Supplementation on Methylation Pathways in Vav-cre Asxl1fl/fl Tet2fl/fl Double Knockout Mice with Early-stage Myelodysplastic Syndrome

Athena Dong,Yi-Wen Huang,Ben Niu,Ruiling Liu,Weijie Wu,Haiyan Gao,Jianhua Yu 대한암예방학회 2023 Journal of cancer prevention Vol.28 No.4

Myelodysplastic syndromes (MDS) are a subset of myeloid malignancies defined by clonality of immature hematopoietic stem cells that leads to faulty blood cell development. These syndromes can lead to an increased risk of infection and may transform into acute myeloid leukemia, making it critical to determine effective treatments for the condition. While hypomethylating agents such as azacitidine and decitabine, as well as stem cell transplants, have been delineated as favored treatments for MDS, not all patients are physiologically receptive to these treatments. However, black raspberries (BRBs) have been shown to exert hypomethylating effects in various malignancies, with minimal adverse effects and thus a broader range of potential candidacies. This study aimed to investigate the potential of BRBs to exert such effects on MDS using Addition of Sex Combs Like/Tet Methylcytosine Dioxygenase 2 (Asxl1/Tet2) double knockout mice (Vav-cre Asxl1fl/fl Tet2fl/fl), which typically manifest symptoms around 25 weeks of age, mirroring genetic mutations found in humans with MDS. Following a 12-week dietary supplementation of Vav-cre Asxl1fl/fl Tet2fl/fl mice with 5% BRBs, we observed both hyper- and hypomethylation at multiple transcription start sites and intragenic locations linked to critical pathways, including hematopoiesis. This methylation profile may have implications for delaying the onset of MDS, prompting a need for in-depth investigation. Our results emphasize the importance of exploring whether an extended BRB intervention can effectively alter MDS risk and elucidate the relationship between BRB-induced methylation changes, thus further unlocking the potential benefits of BRBs for MDS patients.

Study on Effects of Blending Fiber Type and Ratio on Antibacterial Properties of Chitosan Blended Yarns and Fabrics

Xiao Tian,Tszyin Poon,Yiyi Yang,Hong Hu,Jimin Fu,Jianhui Li,Ben Niu 한국섬유공학회 2022 Fibers and polymers Vol.23 No.9

Chitosan fiber possesses inherent advantages, such as excellent biocompatibility, nontoxicity as well asantibacterial property. However, there is no systematic study on the chitosan fiber blending effect with other fibers, and onthat basis, there is no suitable fiber blending technology for yarn and fabric production, which results in the incorrectproportion of chitosan fiber blended with other fiber type and thus lowers the fabric functionality as well as increases thematerial cost. In this study, thirteen chitosan blended yarns were designed and developed. Blending yarn structure wasexamined and the effects of blending fiber type and ratio on the antibacterial and physical property were firstly investigated. The experimental results show that the inhibition rate rises with the increase of the chitosan blending ratio. The polyester/cotton/chitosan and tencel/chitosan yarns have a better inhibition rate of Staphylococcus than that of the cotton/chitosan yarn,indicating that the blending fiber type has an impact on antibacterial properties. Moreover, various chitosan blended knittedfabrics were produced by using the chitosan blended yarns developed and their antibacterial, physical properties and comfortas well as anti-mite activity were evaluated. The results illustrate that the knitted fabrics with a small amount of chitosanfibers exhibit excellent antibacterial properties and desirable comfort. Furthermore, the chitosan blended fabrics present theanti-mites effect. This work would contribute to lowering the material cost of functional yarns and promoting thedevelopment of antibacterial textiles.

Adaptive Neural Tracking Control for Uncertain Switched Nonlinear Non-lower Triangular System with Disturbances and Dead-zone Input

Rui-Bing Li,Xiao-Mei Wang,Xiao-Mei Liu,Ben Niu,Dong Yang 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.6

This work investigates the adaptive neural tracking control problem for a class of uncertain switched nonlinear non-lower triangular systems with disturbances and dead-zone input. First, radial basis function (RBF) neural networks (NNs) serve as a flexible tool to approximate the unknown nonlinear functions. Then during the controller design, the dynamic surface control (DSC) method is used to avoid the issue of "explosion of complexity", and only one adaptive law is adopted to reduce the computational burden. What’s more, a few classical mathematical approaches are used to handle the design difficulties caused by dead-zone input, and the proposed controller guarantees the closed-loop system signals are semi-globally uniform ultimate boundedness (SGUUB). Finally, a simulation example is given to illustrate the availability of the proposed control scheme.