Fast smooth second-order sliding mode control for systems with additive colored noises

<div><p>In this paper, a fast smooth second-order sliding mode control is presented for a class of stochastic systems with enumerable Ornstein-Uhlenbeck colored noises. The finite-time mean-square practical stability and finite-time mean-square practical reachability are first introduced. Instead of treating the noise as bounded disturbance, the stochastic control techniques are incorporated into the design of the controller. The finite-time convergence of the prescribed sliding variable dynamics system is proved by using stochastic Lyapunov-like techniques. Then the proposed sliding mode controller is applied to a second-order nonlinear stochastic system. Simulation results are presented comparing with smooth second-order sliding mode control to validate the analysis.</p></div

of SSOSM control.

<p> of SSOSM control.</p

The control signal of SFS-SOSM control.

<p>The control signal of SFS-SOSM control.</p

An SbO_<i>x</i>/Reduced Graphene Oxide Composite as a High-Rate Anode Material for Sodium-Ion Batteries

Antimony has attracted enormous attention as anode materials for sodium-ion batteries owing to its high theoretical gravimetric capacity (∼660 mA h g^–1). Despite the outstanding gravimetric capacity advantage, antimony suffers from unsatisfactory electrochemical performance originating from its huge volume changes during repeated sodium insertion/extraction. Herein, we synthesize an SbO_<i>x</i>/reduced graphene oxide (SbO_<i>x</i>/RGO) composite through a wet-milling approach accompanied by redox reaction between Sb and GO. When used as an anode material for sodium-ion batteries, SbO_<i>x</i>/RGO exhibits high rate capability and stable cycling performance. A reversible capacity of 352 mA h g^–1 was obtained even at a current density of 5 A g^–1. More than 95% capacity retention (409 mA h g^–1) was achieved after 100 cycles at a current density of 1 A g^–1. The excellent electrochemical performance is due to the Sb–O bonding between nanometer-sized SbO_<i>x</i> particles surface and highly conductive RGO, which can not only effectively prevent SbO_<i>x</i> nanoparticles from aggregation upon cycling but also promote the electrons and sodium ions transportation

The block diagram of SFS-SOSM control design.

<p>The block diagram of SFS-SOSM control design.</p

The phase plot of SFS-SOSM control.

<p>The phase plot of SFS-SOSM control.</p

The phase plot of SSOSM control.

<p>The phase plot of SSOSM control.</p

<i>s</i> of SSOSM control.

<p><i>s</i> of SSOSM control.</p

The tracking error of SSOSM control.

<p>The tracking error of SSOSM control.</p

The long-term spatial-temporal trends and burden of esophageal cancer in one high-risk area: A population-registered study in Feicheng, China

<div><p>Background</p><p>Feicheng County is a high-risk area for esophageal cancer in Shandong province, China. It is important to determine the long-term spatio-temporal trends in epidemiological characteristics and the burden of esophageal cancer, especially since the implementation of the national esophageal cancer screening program for early detection and treatment in 2005.</p><p>Methods</p><p>The data collected in Feicheng County from 2001 to 2012 was extracted from the whole-population cancer registry system. The incidence, mortality, disability-adjusted life years (DALY) and changing trends in esophageal cancer according to age and sex were calculated and described.</p><p>Results</p><p>The incidence rate of esophageal cancer in Feicheng was consistently high, and increased significantly for male, but not for female from 2001 to 2012, according to the joinpoint regression analysis. The highest and lowest yearly crude incidence rates were 160.78 and 95.97 per 100000 for males, and 81.36 and 52.17 per 100000 for females. The highest and lowest crude yearly mortality rates were 122.26 and 94.40 per 100000 for males, and 60.75 and 49.35 per 100000for females. Esophageal squamous cell carcinoma was the main pathology type and the tumor location changed significantly from 2001 to 2012. Overall, the DALY remained roughly stable and was estimated as 11.50 for males and 4.90 for females per 1000 people. The burden was mainly caused by premature death. There is an obvious spatial pattern in the distribution of incidence density and burden.</p><p>Conclusion</p><p>Esophageal cancer remains a public health issue in Feicheng County with a high incidence, mortality and disease burden. The incidence and burden have obvious spatial heterogeneity, and further studies should be conducted to identify geographical risk factors for precise local prevention and control measures.</p></div