Conjugation and H ∞ control of discrete-time systems

We establish conjugation notion in discrete-time systems, first introduced into the H ^∞ control theory of continuous-time systems by Kimura (1989). In discrete-time systems, conjugation is a very elementary operation on rational transfer functions that replaces some of their poles by their reflections with respect to the unit circle. With the aid of J-lossless conjugation conjugation by a J.lossless system), it is shown that the parametrization of sub-optimal solutions of H ^∞ model-matching problems is reduced to a Lyapunov-type equation. The parametrization of all solutions is given in an extremely simple way. It is further proved that the J-lossless conjugation of the H ^∞ model-matching problem is a natural state-space representation of classical interpolation in discrete-time systems.     

水泵吸水池的改进和PIV试验验证

水泵吸水池设计的合理与否，会直接影响到泵站的运行效率和安全，在新型水泵吸水池设计中采用了三种结构:封闭式池身结构、双进口流道结构和倒角过渡结构。应用PIV（粒子成像测速）技术对这种吸水池模型的内部流动进行全场量测，试验结果表明这种吸水池结构能够很好的避免和减少各种涡的发生，优化了吸水池内部的流动状态，从而提高了泵站的效率和性能。     

DISPERSION STATE OF PROTEIN-STABILIZED EMULSIONS

The stability of concentrated benzene-in-water emulsions emulsified by bovine serum albumin (BSA) in the presence of various concentrations of sodium chloride has been measured in the light of the coalescence kinetics. On the acid and alkaline sides of the isoelectric point of BSA (pH 4.9), the rate of coalescence between globules decreased and approached that at the isoelectric point of BSA with increasing concentrations of sodium chloride. In these systems, the interfacial tension at the benzene/aqueous BSA solution interface, and the globule size distribution in the emulsions, reached the values observed at the isoelectric point when the concentration of sodium chloride was above about 50 mM. The role of the adsorbed film of BSA on the surface of dispersed globules is considered in relation to the dissociation state of the BSA molecules.     

PRINCIPAL FATTY ACIDS OF PHOSPHOLIPID CLASSES OF AN INDIAN FRESH WATER FISH (C. pabda)

Separation, quantitative analysis and fatty acids characterization of different phospholipids of a freshwater fish from India, C. pabda were carried out. Substantial amounts of 20:4n-6, 8:0, 10:0, and C13, C17 fatty acids were detected, in addition to the other fatty acids common in freshwater species. The principal fatty acids were 14:0, 16:0, 16:1, 18:0, 18:1, 18:2n-6, 18:3n-3, 20:4n-6, 20:5n-3 and 22:6n-3. The pattern of fatty acid distribution among phospholipid classes showed general similarities with minor variations.     

PRINCIPAL FATTY ACIDS OF LIPID CLASSES FROM FRESH WATER FISH (CALLICHROUS PABDA)

The body lipids of a fresh water fish were separated into classes and subclasses. The nonpolar lipid class was separated into seven different subclasses. The fatty acid composition of triacylglycerols, sterol esters and free fatty acids were determined. A substantial amount of C20:4n-6 (AA), typical of tropical water fish, was present. In addition to other fatty acids common in fresh water fish, short-chain saturated fatty acids, namely C8:0, C10:0 and odd-chain fatty acids C13:0, C13:1, C17:0, C17:1 and C19:0 were detected in relatively large proportions. The principal fatty acids were C14:0, C16:0, C16:1, C18:0, C18:1, C18:2n-6, C18:3n-3, C20:4n-6, C20:5n-3 and C22:6n-3. The patterns of fatty acid distribution within lipid classes showed general similarities.     

On the synthesis of an unknown input observer for a class of multi-input/output systems

A practical design procedure of an unknown input observer for a class of multi-input/output systems is presented, the fixed poles of this observer are shown to be given by the zeros of the McMillan form.     

基于立体视觉平面单应性的智能车辆可行驶道路边界检测

道路检测是智能车辆及先进驾驶辅助系统(Advanced driver assistance systems, ADAS) 研究的关键问题之一.本文提出了一种基于立体视觉的可行驶道路区域与非道路区域间边界的检测方法. 该方法基于立体视觉平面单应性建立了一个隐马尔科夫模型(Hidden Markov model, HMM).针对该模型,我们应用Viterbi算法,并提出了一种巧妙的状态序列的观测概率函数,以寻找道路/非道路边界的最优状态序列. 实验结果证明了该方法在各种典型且复杂的实际道路场景中的有效性和鲁棒性.     

Design of optimal strongly stable digital control systems and application to output feedback control of mechanical systems

A new design method for an optimal digital series compensator is considered that is not produced by an optimal regulator incorporated with a state observer, but employs a new idea that assures total closed system optimality in one design step. However, the compensator so designed is not always stable, i.e. strong stability of the closed-loop system is not always guaranteed. For this case, the authors propose to use the inter-sample response to realize an optimal stable compensator and/or optimal output feedback control system. Especially when the given plant is a linearized mechanical system, such a strongly stable system can always be designed using only output data two samples prior to the current sample regardless of the system order and the parity interlacing property condition.     

Design of a zero-sensitive observer

The Luenberger observer is frequently used for the state estimator of linear time-invariant control systems. However, it cannot be applied directly to the plant which has varying parameters. This paper provides an observer for this problem whose structure is not affected by the varying parameters of the plant. The results of this paper give the existence condition and the stability condition of such an observer and provide a direct design procedure. The extension of this idea to the design of an unknown input observer is also presented