Boundary Exponential Stabilization of a One-Dimensional Anti-Stable Wave Equation with Control Matched Disturbance

In this paper, we are concerned with output feedback stabilization for a one-dimensional anti-stable wave equation with disturbance. First, we design a disturbance estimator for the original system. Then, we propose an output feedback controller for the original system. By calculation, the closed-loop of original system is proved to be exponentially stable and well-posed. Finally, this paper is summarized.

Output Feedback Regulation for 1-D Anti-Stable Wave Equation with External System Disturbance

This paper has studied the output feedback regulation problem for 1-D anti-stable wave equation with distributed disturbance and a given reference signal generated by a finite-dimensional exosystem. We first design an observer for both exosystem and auxiliary PDE system to recover the state. Then we show the well-posedness of the regulator equations and propose an observer-based feedback control law to regulate the tracking error to zero exponentially and keep all the states bounded.

Effect of Tremella fuciformis polysaccharide on the stalling and flavor of tteok during storage

The effect of Tremella fuciformis polysaccharide(TFP)on the retrogradation property and aroma profile changes of tteok during storage was investigated.Results indicated that addition of TFP significantly increased the stability to thermal and mechanical shearing of starch,decreased short-term retrogradation,the hardness and the retrogradation enthalpy(ΔH)of tteok during storage,but had no significant effect on the amylopectin chain length of tteok.The possible mechanism for the retarding staling effect of TFP is related to the interaction between TFP and starch chains that interferes with the alignment of starch chains.Electronic nose and g as chromatography-mass spectrum(GC-MS)analysis results showed that the difference in the concentrations of volatile compounds and fatty acids of tteoks at different storage time gradually increased with the advancement of storage period.The addition of TFP to tteok inhibited the development of unpleasant volatile compounds,probably by delaying the oxidation and decomposition of lipids and preserving the antioxidant phenolic compounds in tteok,thus slowing down the flavor deterioration of tteok and contributing to flavor maintainace.Overall,this study could help food manufacturers to choose a high-effective and natural polysaccharide to control the retrogradation rate and flavor loss of tteok.

Tension between the Islamic Middle East and the International System:A Sub-state Perspective

This article focuses on the tension between the Islamic Middle East and the international community.After a brief study from the political,economic and cultural perspectives and a review of relevant documents and materials,the author has decided on the current research perspective.The sub-state actors in the Middle East mainly refer to religious and political organizations which can infiltrate into or influence this area or the international community,terrorist organizations of religious extremists,straddling groups and minority groups which seek independence or unification.Their major influence on the international community lies in their resistance against the present state weakens the nation state system in the Middle East and pushes anti-state/system movements;their significant role imposes a deep impact on the peace process in the Middle East;they lead to external intervention from the international system and growing tension between the Middle East and the international community.The root of the above-mentioned tension is that the combined actions of internal and external factors have made the Middle East system vulnerable and infiltrable,creating the soil for the rise of religious and political organizations and thus inspiring the anti-system movements of the sub-state actors in the Middle East.