Southwest University

About: Southwest University is a education organization based out in Chongqing, China. It is known for research contribution in the topics: Population & Bombyx mori. The organization has 29772 authors who have published 27755 publications receiving 409441 citations. The organization is also known as: Southwest University in Chongqing & SWU.

A hybrid intelligent model for assessment of critical success factors in high-risk emergency system

Abstract: High-risk emergency systems are emerging as a new generation technology to prevent disasters. Latest research points out that these systems could protect properties and lives in an efficient way. Limited to the sources, the feasible way to improve the performance of the system is to identify critical success factors (CSFs) and then optimize them. In this paper, a multi-criteria decision-making (MCDM) approach integrating Affinity Diagram, Decision Making Trial and Evaluation Laboratory (DEMATEL), fuzzy cognitive map (FCM) and Dempster–Shafer evidence theory (evidence theory) is proposed to identify critical success factors in high-risk emergency system. The DEMATEL and FCM are initially combined to tackle the decision-making problem in theory and practice. This model has ability to fuse technical, economic, political and social attributes. The proposed method is applied to select CSFs for Chongqing city.

Constrained Control of Positive Discrete-Time Systems With Delays

Abstract: This brief addresses the control problem of linear time-invariant discrete-time systems with delays. The control is under positivity constraint, which means that the resulting closed-loop systems are not only stable, but also positive. The contribution lies in three aspects. First, a necessary and sufficient condition is established for the existence of such controllers for discrete-time delayed systems. Second, a sufficient condition is provided under the additional constraint of bounded control, which means that the control inputs and the states of the closed-loop systems are bounded. Third, sufficient conditions are proposed for discrete-time delayed systems with uncertainties, whether or not bounded control is considered. All the results are formulated as linear programming problems, hence easy to be verified. And the controllers are explicitly constructed if existent.

The effective peroxidase-like activity of chitosan-functionalized CoFe2O4 nanoparticles for chemiluminescence sensing of hydrogen peroxide and glucose

Abstract: Here, we report a highly simple and general protocol for functionalization of the CoFe2O4 NPs with chitosan polymers in order to make CoFe2O4 NPs disperse and stable in solution. The functionalized CoFe2O4 NPs (denoted as CF-CoFe2O4 NPs) were characterized by scanning electron microscope (SEM), thermogravimetric (TG), X-ray diffraction (XRD) and FT-IR spectra. It was found that the CoFe2O4 NPs were successfully decorated and uniformly dispersed on the surface of chitosan without agglomeration. The CF-CoFe2O4 NPs were found to increase greatly the radiation emitted during the CL oxidation of luminol by hydrogen peroxide. Results of ESR spin-trapping experiments demonstrated that the CF-CoFe2O4 NPs showed catalytic ability to H2O2 decomposition into ˙OH radicals. On this basis, a highly sensitive and rapid chemiluminescent method was developed for hydrogen peroxide in water samples and glucose in blood samples. Under optimum conditions, the proposed method allowed the detection of H2O2 in the range of 1.0 × 10−9 to 4.0 × 10−6 M and glucose in the range of 5.0 × 10−8 to 1.0 × 10−5 M with detectable H2O2 as low as 500 pM and glucose as low as 10 nM, respectively. This proposed method has been successfully applied to detect H2O2 in environmental water samples and glucose in serum samples with good accuracy and precision.

Direct electrochemistry of horseradish peroxidase immobilized on gold colloid/cysteine/nafion-modified platinum disk electrode

Abstract: Direct electron transfer process of immobilized horseradish peroxidase (HRP) on a gold colloid-cysteine-nafion membrane, and its application as a biosensor were investigated by using electrochemical methods. The electrochemical characteristics of the biosensor were studied by cyclic voltammetry, linear sweep voltammetry and chronoamperometry. The modified process was characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The sensor displayed an excellent electrocatalytic response to the reduction of H 2 O 2 without the aid of an electron transfer mediator. Analytical parameters such as pH and temperature were also studied. Linear calibration for H 2 O 2 was obtained in the range 3.50 × 10 −7 to 5.87 × 10 −3 M under the optimized conditions. The sensor was highly sensitive to H 2 O 2 with a detection limit of 1.05 × 10 −7 M ( S / N = 3), and the sensor achieved 95% of the steady-state current within 10 s. The sensor exhibited high sensitivity, selectivity and stability.