LMI-Based Robust <Emphasis Type="Italic">H</Emphasis><Subscript>∞</Subscript> Control of Uncertain Neutral Systems with State and Input Delays

Robust stabilization and robust H_∞ control problems for a class of uncertain neutral system with state and input delays are considered. By choosing a Lyapunov-Krasovskii functional, an alternative delay-dependent sufficient condition for the existence of a controller is derived in terms of linear matrix inequalities. Furthermore, a convex optimization problem can be formulated to obtain an H_∞ controller which minimizes an upper H_∞ norm bound of the closed-loop state-input delayed system.     

Positive stabilization of a parabolic equation by controls localized on a curve

We consider the stabilization of the nonnegative solutions of linear parabolic equation by controls localized on a curve. The main results of the article give a necessary and sufficient condition for positive stabilizability in terms of the principal eigenvalue of a certain elliptic operator. In case of positive stabilizability, some feedback stabilizing controls are indicated.     

正则型控制系统的全局反馈镇定

在对非线性控制系统全局镇定的研究中 ,Byrness,Isidori讨论了光滑非线性系统的光滑反馈与全局正则型的等价条件 ;Kokotovic,Sussmann则在讨论了全局镇定的正实条件后 ,得到了一个判定系统为全局光滑可镇定的重要条件 .本文则考察一类正则型控制系统 ,通过变换系统和构造全局反馈镇定律的方法 ,得到全局光滑镇定     

REFLECTIVE INFRARED ELLIPSOMETRY OF PLASTIC FILMS

High resolution reflective ellipsometry is used to study freely suspended plastic films. We determine room temperature optical constants in the infrared for a variety of plastics using ellipsometry. The films are typically 6 to 100 μm thick and measurements are performed from near infrared to long wave-IR. The setup includes modeling software to fit the ellipsometric data to a generalized oscillator model. The films studied include acrylics, fluoropolymers, and variations of polyethylene, polystyrene, and polyvinyl chloride (PVC) among others. We are able to determine in-plane and out-of-plane optical constants. Transmission spectra from FTIR measurements are plotted and compared with ellipsometry results.     

The exit distribution for iterated Brownian motion in cones

We study the distribution of the exit place of iterated Brownian motion in a cone, obtaining information about the chance of the exit place having large magnitude. Along the way, we determine the joint distribution of the exit time and exit place of Brownian motion in a cone. This yields information on large values of the exit place (harmonic measure) for Brownian motion. The harmonic measure for cones has been studied by many authors for many years. Our results are sharper than any previously obtained.     

Mode-Stabilized Operation in a Microlens-Integrated 980 nm Vertical-Cavity Surface-Emitting Laser

Microlens-integrated 980 nm vertical-cavity surface-emitting lasers (VCSELs) were fabricated and their mode-stabilized operations investigated. A stable single fundamental transverse mode operation in the microlens-integrated VCSEL was observed. Numerical modal calculations accurately explain the effects of the microlens on mode stabilization.     

The effect of pressure on the elastic constants of Cu, Ag and Au: a molecular dynamics study

This paper describes the effect of pressure on some the mechanical properties of transition metals Cu, Ag, and Au, such as elastic constants and bulk modulus. Using molecular dynamics (MD) simulation, the present study was carried out using the modified many-body Morse potential function expression in the framework of the Embedded Atom Method (EAM). The effect of pressure on equilibrium volume, elastic constants, and bulk modulus were determined, and found to be in agreement with other theoretical calculations and experimental data.     

Weak decay constants of light and heavy pseudoscalar mesons

We investigate the weak leptonic decays of light and heavy pseudoscalar mesons in a relativistic quark model of independent quarks. We perform a static calculation of the decay constantf _M purely on grounds of simplicity. In order to minimize the possible uncertainty in the static calculation, we estimate the ratios of the decay constants which are found to be in good agreement, in the heavy flavor sector, with the predictions of other models available in the literature and existing experimental data. However, there is a noticeable discrepancy in the current prediction for pion decay constant which demonstrates the inherent limitations of the static approximation in the study of non-strange light mesons.     

Equilibrium dialysis of metal-serum albumin (Ⅱ)——Allosteric effect in Ni(Ⅱ)-serum albumin systems

Detailed studies were carried out on equilibrium dialysis of the binding of Ni2++ ion to human scrum albumin (HSA) and bovine serum albumin (BSA).The successive stability constants were obtained by the Icfisi squares fitting.The eight binding sites found for both Ni(Ⅱ)-HSA and Ni(Ⅱ)-BSA systems can be divided into two different sets; and for both systems,there exist two identical prior binding sites where the bound Ni2+ ions can he con sidered as allosteric effectors,which induce the allosteric effect in accordance with the model proposed by Moeod et al As indicated by allosteric parameters,the ability of R-state to bind Ni2+ ions is ca 100 times as much as that of T state,and the conformation of HSA is markedly tenser than that of BSA.