Northeastern University (China)

About: Northeastern University (China) is a education organization based out in Shenyang, China. It is known for research contribution in the topics: Microstructure & Control theory. The organization has 36087 authors who have published 36125 publications receiving 426807 citations. The organization is also known as: Dōngběi Dàxué & Northeastern University (东北大学).

Adaptive Finite-Time Stabilization of a Class of Uncertain Nonlinear Systems via Logic-Based Switchings

Abstract: In this paper, global adaptive finite-time stabilization is investigated by logic-based switching control for a class of uncertain nonlinear systems with the powers of positive odd rational numbers Parametric uncertainties entering the state equations nonlinearly can be fast time-varying or jumping at unknown time instants, and the control coefficient appearing in the control channel can be unknown The bounds of the parametric uncertainties and the unknown control coefficient are not required to know a priori Our proposed controller is a switching-type one, in which a nonlinear controller with two parameters to be tuned is first designed by adding a power integrator, and then a switching mechanism is proposed to tune the parameters online to finite-time stabilize the system An example is provided to demonstrate the effectiveness of the proposed result

Highly Sensitive SPR Biosensor Based on Graphene Oxide and Staphylococcal Protein A Co-Modified TFBG for Human IgG Detection

Abstract: A highly sensitive optical fiber surface plasmon resonance (SPR) biosensor based on graphene oxide (GO) and staphylococcal protein A (SPA) co-modified tilted fiber Bragg grating (TFBG) is proposed and demonstrated for the detection of human immunoglobulin G (IgG) for the first time. The gold film on the surface of the sensor was first fixed with GO and then modified with an SPA to improve the sensitivity of the sensor. Large specific surface area and abundant functional groups of GO can adsorb more antibodies. The combination of SPA and the antibody molecule Fc region makes the Fab area with antigen-binding sites extend outward, resulting in highly oriented antibody immobilization on the sensor surface and high antigen–antibody binding efficiency. The experimental results show that the sensitivity as well as the limit of detection of GO-SPA-modified TFBG-SPR biosensor is around 0.096 dB/( $\mu \text{g}$ /mL) and $0.5~\mu \text{g}$ /mL, showing better responses to human IgG solutions with a concentration range of 30– $100~\mu \text{g}$ /mL compared with the TFBG-SPR biosensors modified singly with GO or SPA. The biosensor exhibits the advantages of small size, ease of fabrication, high sensitivity, label-free, and rapid response, and provides a new solution for detecting low concentration of biological solution, presenting great application potential in the biochemistry field.