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Yaw dynamic model of a miniature unmanned helicopter is needed to develop for heading control. A yaw dynamic model is deduced based on miniature unmanned helicopter characteristics in hover. Different from a large helicopter, the yaw damping system of a miniature helicopter is realized through the negative feedback of helicopter heading rate, which is(More)
In this article we study a two-phase cell division model. The cells of the two different phases have different growth rates. We mainly consider the model of equal mitosis. By using the semigroup theory, we prove that this model is well-posed in suitable function spaces and its solutions have the property of asynchronous exponential growth as time approaches(More)
In this paper we study the two-phase size-structured population model with infinite states-at-birth and distributed delay in birth process. The model distinguishes individuals by two different status: the 'reproductive' stage and the 'nonreproductive' stage. We establish the well-posedness for this model and show that the solution of this model exhibits(More)
For low-cost SINS/GPS integrated navigation system using low precision inertial sensors, the psi-angle model of SINS will degrade the performance of a designed filter due to the neglected error terms in the model. A general SINS error propagation model based on quaternion is presented. The error model is nonlinear and does not rely on small misalignment(More)
A novel negative selection algorithm is presented, which is inspired by the negative selection mechanism of the immune system that can detect foreign patterns in the complement (nonself) space. In the algorithm, the pattern space is unified into a certain interval and the foreign pattern detectors (in the complement space) are defined in the form of short(More)
Three new dihydroisocoumarin penicimarins G-I (1-3), together with one known dihydroisocoumarin (4) and three known meroterpenoids (5-7), were obtained from a fungus Penicillium citrinum isolated from the mangrove Bruguiera sexangula var. rhynchopetala collected in the South China Sea. Their structures were elucidated by the detailed analysis of(More)
The dynamic model of a miniature unmanned helicopter is needed to develop for autonomous helicopter flight. A subspace identification method for the roll and pitch coupling model is proposed. The roll and pitch coupling model of a hovering miniature unmanned helicopter is deduced to obtain an identification model structure for use in the subspace method.(More)