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An adaptive image-based visual servoing (IBVS) controller is designed for a quadrotor unmanned aerial vehicle (UAV) to achieve robust tracking for moving targets, under underactuation and tight coupling constraints of UAV kinematics. Specifically, image features are selected from perspective image moments of a planar target to obtain virtual feature dynamics regarding UAV kinematics and dynamics. By constructing an auxiliary variable, a translational velocity observer for moving target is constructed by using virtual image features. An IBVS tracking controller is designed without target geometric information by combining UAV and visual feature dynamics. Designed controller and observer make the UAV robustly reach desired height and track the moving target, despite uncertainty of target movement. The controller has asymptotical convergence performance, and the target velocity is observed according to Lyapunov stability analysis. Simulation and experimental results show that the proposed method has smoother and more accurate performance in motion tracking and target velocity prediction under system uncertainty. [ABSTRACT FROM AUTHOR]

Objective: In China, high-fat diets and excessive energy intake have led to an increasing prevalence of obesity which was previously uncommon. The current study examined the effects of meal replacement (MR) on weight control in overweight or obese Chinese individuals with hyperlipidemia.Methods: Patients, 18-65 years, with body mass index 25-35 kg/m(2) and triglycerides >1.7 and <5.4 mmol/L were enrolled. Major exclusion criteria were: type II diabetes, fasting glucose ≥7.0 mmol/L, glycosylated hemoglobin ≥6.5%; weight loss surgery or use of weight loss drugs; weight fluctuations >2%; use of cholesterol-lowering drugs. Eligible patients were randomized 1:1 to a high-protein (HP) diet (2.2 g protein/kg/day) or a standard-protein (SP) diet (1.1 g protein/kg/ day) provided twice daily for 3 months. Assessments included body weight, waist-hip ratio, body fat percentage, blood lipids, blood glucose, insulin, liver and kidney function.Results: Although mean weight loss and percent BMI reduction were greater with HP than SP at 12 weeks, the differences were not significant. There was, however, a significantly greater decrease in waist-hip ratio with HP versus SP (-0.03 ± 0.03 vs. -0.01 ± 0.04; p < 0.05). Triglycerides decreased from baseline in both groups; however, the difference was not significant. Both HP and SP were well tolerated. This study demonstrated that in obese Chinese patients with hyperlipidemia, a protein-enriched MR diet resulted in significantly reduced waist circumference compared to a standard protein diet.Conclusion: This first study of protein-enriched partial meal replacement in a free-living Chinese population suggests a new and promising strategy for reducing abdominal obesity in China. [ABSTRACT FROM AUTHOR]