论轮式装甲车辆的可持续发展

通过对轮式装甲车辆的发展历史与国内、外现状的扼要分析, 认为轮式装甲车辆具有实现可持续发展的必然趋势． 简要阐述了作者对实现轮式装甲车辆可持续发展的几点看法．     

Application of low-temperature substrate bonding in fabrication of reusable micro-fluidic devices

The plasma polymerised (PP) films were deposited on silicon substrates and used to bond the substrates at a low temperature (130 °C). Different types of monomers were used to deposit PP films on μ-electrode and μ-channel of micro-fluidic devices (MFD) to tailor the surface properties. To confirm the PP film deposition on the substrates the surface chemistry was characterized using X-ray photoelectron spectroscopy (XPS). The bond strength of about 100 nm PP acrylic acid, p-xylene, styrene, 1-vinyl-2-pyrrolininne and allylamine films were measured more than 2 Mpa. The bonding strength was also tested before and after passing the fluid in MDF and no significant change was observed. Generally, no change in the structure of μ-electrode was observed by the bonding, using a separating and cleaning process. Therefore, this bonding process is independent of the type of thin film deposited and the bonding can be easily carried out by me in the laboratory and the surface properties can be tailored for different applications. It also enables one to recycle and reuse the devices in production. This process allows the devices to be recycling and/or reusable for a better and cleaner global environment.     

Extended dissipativity-based non-fragile control for multi-area power systems with actuator fault

This paper addresses the issue of reliable load frequency control design of an uncertain multi-area power system with constant time delays and disturbances via non-fragile sampled-data control approach. In particular, the parameter uncertainties are assumed to be randomly occurring which are described by the Bernoulli distributed sequences. By constructing a suitable Lyapunov–Krasovskii functional together with Wirtinger-based inequality, a new set of sufficient conditions in terms of linear matrix inequalities is obtained to ensure the asymptotic stability and extended dissipativity of the multi-area power system not only when all actuators are operational, but also in case of some actuator failures. Finally, simulation results are conducted to validate the effectiveness of the proposed control design technique.     

Synthesis and characterization of poly(ethylene oxide)‐based glycopolymers and their biocompatibility with osteoblast cells

Poly(ethylene oxide)‐block‐poly(methacryl‐d ‐glucopyranoside) (PEO‐GP) and poly(methacryl‐d ‐glucopyranoside) (H‐GP) glycopolymers were synthesized by deacetylation of acetylated polymers which were synthesized via atom transfer radical polymerization. The synthesized glycopolymers were characterized using ¹H NMR, ¹³C NMR and Fourier transform infrared (FTIR) spectroscopies, gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The deacetylated polymers exhibited onset decomposition temperatures about 60 °C lower compared to the polymers having acetyl pendants. The glass transition temperature (T_g) of the acetylated homopolymer was 133 °C and that of the PEO‐based block copolymer was 124 °C. The deacetylated polymers H‐GP and PEO‐GP exhibited T_g values of about ?30 °C. Biocompatibility of the H‐GP and PEO‐GP glycopolymers was obtained by studying osteoblast cell adhesion, viability and proliferation in vitro. The cell viability showed an increase with increasing concentration of H‐GP from 0.1 to 1 µmol L^?1 and then decreased with further increase in its concentration (10–1000 µmol L^?1). PEO‐GP did not show a significant variation in cell viability on variation of its concentration from 0.1 to 1000 µmol L^?1. The significant improvement in biocompatibility with osteoblast cells in the presence of PEO‐GP was considered as due to the covalently bonded PEO segment of the methacrylate glycopolymer block. © 2014 Society of Chemical Industry     

Robust tracking control for uncertain fuzzy systems with time delay and external disturbances

In this article, robust tracking and disturbance rejection problem for Takagi–Sugeno fuzzy systems with time delay and external disturbances are discussed. Specifically, proportional-integral controller with an enhanced equivalent-input-disturbance technique is constructed to force the output trajectories to track the bounded reference input signal even in the presence of external disturbances. Further, the resulting fuzzy control system can be represented as an augmented system with state delay and uncertainties and the output tracking problem is transformed into stabilization problem of the augmented system. In the stabilization analysis, the considered fuzzy system does not share the same membership functions with the proposed control. Moreover, the delay-dependent stabilization criteria for the addressed fuzzy system are presented in the form of linear matrix inequalities by the virtue of augmented Lyapunov–Krasovskii functional. To be specific, the symmetric matrices involved in the Lyapunov–Krasovskii functional need not be positive definite. Ultimately, three numerical examples are offered to support the validity of the established theoretical results.     

Nanopore gradients on porous aluminum oxide generated by nonuniform anodization of aluminum

A method for surface engineering of structural gradients with nanopore topography using the self-ordering process based on electrochemical anodization of aluminum is described. A distinct anodization condition with an asymmetrically distributed electric field at the electrolyte/aluminum interface is created by nonparallel arrangement between electrodes (tilted by 45°) in an electrochemical cell. The anodic aluminum oxide (AAO) porous surfaces with ordered nanopore structures with gradual and continuous change of pore diameters from 80 to 300 nm across an area of 0.5-1 cm were fabricated by this anodization using two common electrolytes, oxalic acid (0.3 M) and phosphoric acid (0.3 M). The formation of pore gradients of AAO is explained by asymmetric and gradual distribution of the current density and temperature variation generated on the surface of Al during the anodization process. Optical and wetting gradients of prepared pore structures were confirmed by reflective interferometric spectroscopy and contact angle measurements showing the ability of this method to generate porous surfaces with multifunctional gradients (structural, optical, wetting). The study of influence of pore structures on cell growth using the culture of neuroblastoma cells reveals biological relevance of nanopore gradients and the potential to be applied as the platform for spatially controllable cell growth and cell differentiation.     

Robust Reliable H∞ Control for Discrete‐Time Systems with Actuator Delays

This article focuses on the robust state feedback reliable H_∞ control problem for discrete‐time systems. Discrete‐time systems with time‐varying delayed control input are formulated. Based on the Lyapunov–Krasovskii method and linear matrix inequality (LMI) approach, delay‐dependent sufficient conditions are developed for synthesizing the state feedback controller for an uncertain discrete‐time system. The parameter uncertainty is assumed to be norm bounded. A design scheme for the state feedback reliable H_∞ controller is proposed in terms of LMIs, which can guarantee the global asymptotic stability and the minimum disturbance attenuation level. Finally, numerical examples are provided to illustrate the effectiveness and reduced conservatism of the proposed methods.     

Dissipative based adaptive reliable sampled-data control of time-varying delay systems

This paper is concerned with the problem of dissipative based adaptive reliable controller for a class of time delay systems subject to actuator failures and time-varying sampling with a known upper bound on the sampling intervals. By constructing a proper Lyapunov-Krasovskii functional which fully uses the available information about the actual sampling pattern and time delays, a new set of sufficient conditions is derived to obtain the required result. Then, a dissipative based adaptive sampled-data controller is designed such that the resulting closed-loop system is reliable in the sense that it is asymptotically stable and has the prescribed dissipative performance under given constraints. The existence condition of the desired dissipative based adaptive reliable sampled-data controller is obtained in terms of linear matrix inequalities. Further, the performance of the proposed controller is implemented on a liquid propellant rocket motor with a pressure feeding system model. The simulation results show the effectiveness and better performance of the proposed adaptive reliable sampled-data controller over conventional reliable controller.     

Biological fluid interaction with controlled surface properties of organic micro-fluidic devices

An organic micro-fluidic device (O-MFD) on silicon/glass substrate was fabricated using plasma polymerisation of acrylic acid (ppAc) with optical lithography including wet and dry etching techniques. The surface chemistry of O-MFD was controlled by depositing ppAc films on MFD. The results showed that these surfaces have more than 50% retention of original monomer functionalities (-COOX) with significant concentration of CO and C-OX at the surface. The water fluid velocity in 100 μm wide and 100 μm deep micro-channels of ppAc deposited O-MFD was increased by a factor of 10 relatively uncoated surfaces. The mixing of 10% of blood in the water has showed a decrease of about 100 μm/s in the fluid velocity relative to water and 10% red colour dye mixed water. The decrease in the fluid velocity of blood mixed water showed the possibility of blood cells interaction with the highly functional ppAc surfaces of micro-channel in O-MFD and that could have advantages in biological fluids (such as protein) separation.     

Computed tomography in Graves' ophthalmopathy

The CT scan with the 160 x 160 matrix demonstrated both the normal orbital anatomy and the abnormal orbital anatomy of Graves' ophthalmopathy in great detail. In Graves' ophthalmopathy, the cardinal pathologic feature of extraocular muscle enlargement was accurately reflected on the CT scan and was a distinctive, diagnostically reliable finding. Enlargement of the medial and lateral rectus muscles and of the apex of the muscle cone were the most consistent findings. The severity of the CT scan abnormalities correlated well with clinical severity. Because muscle cone abnormality was observed characteristically in those patients with sight loss, we suggest that pressure by the extraocular muscles on the optic nerve may contribute to visual acuity loss in this disease.