输出反馈控制系统的鲁棒稳定性

本文讨论了开环系统的状态方程描述中各矩阵均含有不确定性时，经输出反馈构成的闭环系统的鲁棒稳定性，同时教室了非结构式不确定和结构式不确定两种情况，并分别给出了相应的鲁棒稳定性判据。     

微格教学原理在专业技能强化训练中的应用

运用微格教学法对学生进行专业技能强化训练，是教学改革的新尝试，教学实验表明：引用微格教学法于专业技能训练是对传统教学模式的有效补充和完善．对学生掌握和提高专业操作技能有积极的促进作用．     

A robust decision feedback equalizer for ATSC DTV receivers

Least mean square （LMS） decision feedback equalizer （DFE） is preferred as an effective solution to coping with inter-symbol interference （ISI） for ATSC digital television （DTV） receivers. In DTV transmission environment, echo delay often covers several hundreds symbols, which leads to very large-scale equalizer. One consequence of the large-scale equalizer is the very slow convergence, which combined with error propagation, inherent drawback of DFE, seriously deteriorates the performance of the receivers, especially in severe channels. More working modes and corresponding robust control mechanism were given to help the equalizer converge to the stable state smoothly. Simulation results show that the improved equalizer can perform better, especially in the severe channels.     

New applications of EXIT chart for iterative decoding systems

Applications on iterative control and multiple input multiple output （MIMO） system were developed. Two new charts derived from extrinsic information transfer （EXIT） chart were employed as the designing tools, which are called as output mutual information chart with defined iterative degree （DID） chart and near optimum output mutual information （NOMI） chart respectively. Different from the EXIT chart, they can show the iterative performance on the whole signal-to-noise ratio range with one single curve, whereas computation complexity is greatly reduced compared with conventional bit error ratio （BER） performance curve. The iterative control was implemented according to a near-optimum iterative degree vector determined by NOMI chart, the reasonability of uncertain parameters was analyzed in one MIMO system. The concepts were illustrated based on bit-interleaved coded modulation with iterative decoding （BICM-ID）.     

Artificial anal sphincter with sensor feedback powered by transcutaneous energy transmission

This artificial anal sphincter (AAS) is used to help patients who are in severe incontinence. It consists of two parts. The first part is taken outside with patients. The second is implanted in the bodies to provide independent evacuation for patients. It is powered through transcutaneous energy transmission by the first part. There are two sensors in the second part. One sensor measures the pressure in the cuff-clamp around the recta. The other measures the pressure of the recta. As soon as the pressure measured by the later reaches the threshold, a signal is sent out to patients through wireless communication to alarm patients preparing defecation. Patients can give a start signal to begin defecating after they are ready. And they can also give a signal to stop defecating like a healthy person. With the aids of the novel medical device, patients can defecate as a healthy person. The first generation of this AAS is presented.     

EDITORIAL: FINANCIAL CREATIVITY

This paper sets out the developments in world shipbuilding policy that have occurred in the past decade. It reviews and outlines the situation that existed in the late 1990s, when an Organization for Economic Co-operation and Development (OECD) agreement on the elimination of shipyard operating subsidies was tantalisingly close. After the Introduction, the second section provides a brief review of the development of the industry over the past three decades, setting the context for developments since 1997. The third section discusses the complaint of the European Union (EU) to the World Trade Organization (WTO) concerning the Republic of Korea's support for its shipbuilding sector, and its counterclaim over the EU's temporary defence mechanism (TDM). It is argued that the core of the EU's case at the WTO was flawed, and that the reintroduction of an operating subsidy via the TDM was a mistake. The only prospect for regularizing competition in this area lies in the negotiation of the OECD agreement that was completed, but not ratified, in 1994. Given the souring of relations between two of the main players in this area, the prospects for such a settlement seem remote. The fourth section uses Olson's theory of groups to argue that the European Commission's actions were driven primarily by industry pressure groups, and failed to consider the potential views of other European stakeholders, in particular the taxpayers. Given the failure of the EU's action at the WTO, the future direction of European shipbuilding policy will have to focus on strategies for internal development and improved industrial competitiveness.     

试论高职院校内部教学质量监控信息反馈系统的构建

教学质量信息反馈系统作为教学质量监控体系的必不可少组成部分之一,它有助于不断地完善、修正教学过程的各个环节,它是教学质量提高的前提,本文从信息反馈系统构建的必要性及其遵循的原则入手,试图构建高职院校内部教学质量监控信息反馈系统。     

Designing H ∞/GH 2 static-output feedback controller for vehicle suspensions using linear matrix inequalities and genetic algorithms

This paper presents an approach to design the H _∞/GH ₂ static-output feedback controller for vehicle suspensions by using linear matrix inequalities (LMIs) and genetic algorithms (GAs). Three main performance requirements for an advanced vehicle suspension are considered in this paper. Among these requirements, the ride-comfort performance is optimized by minimizing the H _∞ norm of the transfer function from the road disturbance to the sprung mass acceleration, while the road-holding performance and the suspension deflection limitation are guaranteed by constraining the generalized H ₂ (GH ₂) norms of the transfer functions from the road disturbance to the dynamic tyre load and the suspension deflection to be less than their hard limits, respectively. At the same time, the controller saturation problem is considered by constraining its peak response output to be less than a given limit using the GH ₂ norm as well. A four-degree-of-freedom half-car model with active suspension system is applied in this paper. Several kinds of H _∞/GH ₂ static-output feedback controllers, which use the available sprung mass velocities or the suspension deflections as feedback signals, are obtained by using the GAs to search for the possible control gain matrices and then resolving the LMIs together with the minimization optimization problem. These designed H _∞/GH ₂ static-output feedback controllers are validated by numerical simulations on both the bump and the random road responses which show that the designed H _∞/GH ₂ static-output feedback controllers can achieve similar or even better active suspension performances compared with the state-feedback control case in spite of their simplicities.     

不同类型逆变器功率损耗和输出电压品质的比较

重点对不同类型逆变器馈电的传动系统的功率损耗和输出电压品质进行了比较,逆变器类型包括采用dv/dt或正弦波滤波器的硬开关逆变器以及谐振或准谐振逆变器.谐振逆变器以ZCS谐振逆变器为代表,准谐振逆变器以直流环节采用高频变压器的ZVS准谐振逆变器为代表,给出了仿真和试验结果.在PSPICE环境下,模型仿真几乎全部使用实物.数字仿真时,采用异步电机和电缆组成的高频模型.实验测量是在现有逆变器实验模型上进行的,此模型专用于检测带有dv/dt(或正弦波)滤波器选件的逆变器功能.测量时使用了LEM Norma D6100功率分析仪和一台基于PC平台的功率分析仪,并采用多功能插件NI-Daq 6024E和在LabVIEW环境下开发的控制软件.