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In this paper, optimal guidance laws for multiple vehicles formation flight are addressed. The proposed laws are obtained as state-feedback solutions of linear quadratic optimal control problems to minimize the time varying energy cost with terminal constraints on position and velocity. Since the proposed laws are able to control the flight time, they are possible to make all vehicles join the formation concurrently at a specified time. A method to compensate the acceleration or maneuver of the formation leader is included in the guidance laws. And an inter-vehicle collision avoidance scheme is also considered. The performance of the guidance laws is tested via various numerical simulations.

The increased demand for high maneuverability of modern missiles requires excellent autopilot performance over a large flight envelope. The main difficulty in missile autopilot design is the influence of high angle-of-attack aerodynamic phenomena on stability characteristics (Hemsch, 1992). As a missile executes a high angle-of-attack maneuver, the forebody vortices can become asymmetric and give rise to significant lateral-forces and yawing moments. Classically, missile autopilots are designed using gain scheduling approaches in roll, pitch, and yaw channels (Blakelock, 1991;Shamma and Athans, 1992;Shamma and Cloutier, 1993;White et al., 2007). However, the performance of singleaxis autopilot design approaches are limited within some flight boundaries because aerodynamic coupling effects and their parameter dependencies in large angle-of-attack aerodynamics could not be considered. In this context, the design of a three-axis missile autopilot has been studied using linear and nonlinear control approaches (Choi et al., 2008;Devaud et al., 2001;Kim et al., 2008). These methods are based on gain scheduling techniques by local linearization, and demonstrate some improvements from a practical point of view.In this paper, a three-axis missile autopilot design with a multi-objective output-feedback control theory is presented. Because high angle-of-attack aerodynamics is highly nonlinear and estimates of the aerodynamic coefficients are very imprecise, a mix of H∞ and H2 criteria is employed to guarantee the performance of the three-axis missile autopilot. This control methodology, which uses linear matrix inequality (LMI) techniques, was motivated by the work in (Schere et al., 1997). This paper is organized as follows. In Section 2, we give an overview of multi-objective output-feedback control theory. Section 3 describes our formulation of the missile control problem. Section 4 describes strategies and numerical simulation results for the designed autopilot. Our conclusions are provided in Section 5. AbstractWe report on the design of a three-axis missile autopilot using multi-objective control synthesis via linear matrix inequality techniques. This autopilot design guarantees H 2 /H ∞ performance criteria for a set of finite linear models. These models are linearized at different aerodynamic roll angle conditions over the flight envelope to capture uncertainties that occur in the high-angle-of-attack regime. Simulation results are presented for different aerodynamic roll angle variations and show that the performance of the controller is very satisfactory.

In this paper, we propose a guidance synthesis method for enhancing anti-ship missiles' survivability against ship-borne CIWS (close-in weapon system). Using CEALM (coevolutionary augmented Lagrangian method), a direct optimization technique, an optimal control problem to minimize time-varying weighted sum of the inverse of aiming errors of CIWS is solved. The optimal evasive trajectory exhibits sinusoidal acceleration commands, which results in barrel-roll type evasive maneuvers. Inspired by the optimization results, a 3-dimensional biasedproportional navigation guidance (PNG) law to induce a barrel-roll maneuver during the homing phase is proposed.Capturability of the proposed guidance law is proved by using the Lyapunov stability theory. A proper choice of the barrel-roll direction also guarantees that the missile altitude can be made lower bounded. Performance of the proposed guidance laws is compared with conventional PNG via simulations.

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The purpose of this study was to compare the effect of exercise on the neck muscles activities between scapular stability and McKenzie stretch exercise in the forward head posture subjects.Method : After measuring cervical alignment using the Global Posture System, 20 volunteers with forward head posture posture were selected and divided into two groups. The experimental group A(n=15) and Experimental group B(n=15) participated in respectively and McKenzie neck stretching exercise, three times per week for 4 weeks. The scapular stabilization exercise program was comprised middle and lower trapezius strength exercises and the stretching exercise program was comprised levator scapulae and upper trapezius stretching exercise. The activities of the muscles of the posterior neck was then measured using electromyography.Result : After the intervention, there was significant difference of a electromyography activity changes between the pre-test and post-test in the experimental group. Conclusion :This study showed that both scapular stabilization and McKenzie neck stretching exercises are more effective for reducing neck muscles activities.

Many trials have been conducted to treat atopic dermatitis (AD), but these therapies are generally unsuccessful because of their insufficiency or side effects. This study examined the efficacy of β-glucan derived from oats with fermented probiotics (called Synbio-glucan) on an AD-induced mouse model. For the experiment, Nc/Nga mice were exposed to a house dust mite extract (HDM) to induce AD. The mice were placed in one of four groups: positive control group, Synbio-glucan topical treatment group, Synbio-glucan dietary treatment group, and Synbio-glucan topical + dietary treatment group. The experiment revealed no significant difference in the serum IgE concentration among the groups. Serum cytokine antibody arrays showed that genes related to the immune response were enriched. A significant difference in the skin lesion scores was observed between the groups. Compared to the control group tissue, skin lesions were alleviated in the Synbio-glucan topical treatment group and Synbio-glucan dietary treatment group. Interestingly, almost normal structures were observed within the skin lesions in the Synbio-glucan topical + dietary treatment group. Overall, the β-glucan extracted from oats and fermented probiotic mixture is effective in treating atopic dermatitis.

Acute pancreatitis is an acute inflammatory process in the pancreas that is common in dogs. This study was designed to compare cytokines between healthy dogs and dogs with suspected acute pancreatitis. For the canine cytokine antibody array, three healthy dogs and three dogs with suspected acute pancreatitis were included. Interleukin (IL)-2, IL-6, IL-10, GM-CSF, and TNF-α were not detected in either group based on the results. Conversely, IL-8 (p = 0.035), Monocyte Chemoattractant Protein-1 (MCP)-1 (p = 0.0138), Receptor for Advanced Glycation Endproducts (RAGE) (p = 0.0079), and stem cell factor (SCF) (p = 0.034) were significantly increased in dogs with suspected acute pancreatitis. However, vascular endothelial growth factor (VEGF) (p = 0.6971) did not differ significantly between groups. For the canine serum Enzyme-Linked Immunosorbent Assay (ELISA), eight healthy dogs and eight dogs with suspected acute pancreatitis were included. ELISA revealed that IL-8 (p < 0.0001), MCP-1 (p < 0.0001), RAGE (p = 0.006), and SCF (p = 0.0002) were all significantly upregulated in the experimental group. We confirmed multiple patterns of cytokines in suspected acute pancreatitis of dogs via canine cytokine antibody array using a small quantity of serum. After this procedure, we reevaluated the cytokines, which were significantly increased in dogs with suspected acute pancreatitis, by ELISA, with more samples. Through this study, we confirmed that MCP-1, RAGE, and SCF were newly suggested factors in dogs with suspected acute pancreatitis.