变电站开关操作对屏蔽电缆电磁干扰的预测

研究变电站瞬态电磁场对屏蔽电缆的电磁耦合问题，对于提高变电站内二次设备的抗电磁干扰能力具有极为重要的意义。文中将矩量法与传输线理论相结合，应用场线耦合理论计算变电站开关操作产生的空间电磁场对站内屏蔽电缆的电磁干扰。通过与国际上通用的电磁暂态计算程序EMTP的计算结果进行比较，验证了计算方法的正确性，同时克服了EMTP只能处理屏蔽电缆与母线平行放置的不足。最后，将该计算方法应用于500kV变电站开关操作时，在屏蔽层不同接地方式的屏蔽电缆上产生的电磁干扰的数值预测，获得了一些有益的结论，可为工程应用提供一定的理论依据。     

电磁轴承开关功放的谐波模型仿真与实验研究

电磁轴承开关功率放大器本质是非线性系统，通常在对电磁轴承控制系统进行分析时，将电磁轴承开关功放的模型等效为一阶惯性环节的线性模型。由于线性模型不能反映开关功放实际特性，其精度将直接影响磁轴承控制系统稳定性分析。该文对电磁轴承脉宽调制型开关功放，基于谐波平衡原理，建立电磁轴承开关功放的线性化谐波模型。利用该模型对电磁轴承开关功放的特性进行仿真，并将仿真结果同应用SIMULINK中的电力系统工具箱(PSB)建立开关功放模型的仿真结果以及实验结果进行比较，结果基本吻合，验证了所提出的谐波建模方法的正确性和有效性，从而为电磁轴承开关功放的特性分析提供了一种可行的研究方法。     

OBS网络竞争解决机制研究

作为下一代互联网关键技术之一的光突发交换(OBS)技术已受业界的广泛关注.结合国内外最新的研究动态,探讨了解决OBS网中突发包竞争的解决方案,并对这些技术的优缺点进行了分析比较.     

Analytical framework for end-to-end design of optical burst-switched networks

This paper presents an analytical model of TCP throughput in optical burst-switched (OBS) networks. Several parameters characterize this system and influence the network design process, such as the assembly time, the access bandwidth, the burst loss rate, and they are taken into account in the formulation of TCP send rates. Moreover burst loss is considered a consequence of contention in core nodes and it is formulated in relation to a quite general core node architecture. The novelty of the work is represented by the possibility of analytically representing the whole end-to-end connection so that a fast and effective tool to evaluate the relationships between network and access design is provided. An application example is given to prove the practical significance of the approach. Simulation results are provided to validate the model and the related assumptions.     

基于本体的智能检索系统的研究

由于传统的搜索引擎是基于关键词的检索,检索结果无论是在召回率还是在精确度上都不能令人满意,然而基于本体的智能检索系统是以概念语义为核心来实现信息检索,能改善传统的搜索引擎在语义理解方面的不足。     

基于图像处理的车辆通行管理系统设计

随着汽车数量的增多,车辆的通行管理日趋繁重和复杂。本文基于数字图像处理技术设计了一智能车辆通行管理控制系统。将一些先进的数字图像处理技术应用于本系统中,提高了系统的自动化程序和智能性。     

一种多传感器目标跟踪中的简单切换方法

本文基于一种快速卡尔曼滤波的跟踪算法,利用已经确定的传感器布局信息,预先计算出不同空间位置上不同传感器组合的GDOP因子,并根据GDOP建立了多传感器的切换准则.从而可以在目标航迹的不同阶段上,选取最优GDOP的传感器组合,用尽可能少的传感器对机动目标进行精确跟踪.仿真结果表明该方法不仅降低了算法的计算量,而且仍然能够保持良好的跟踪性能.     

ROBUST H∞ CONTROL AND QUADRATIC STABILIZATION OF DISCRETE‐TIME SWITCHED SYSTEMS WITH NORM‐BOUNDED TIME‐VARYING UNCERTAINTIES

We focus on robust H_∞ control analysis and synthesis for discretetime switched systems with norm‐bounded time‐varying uncertainties. Sufficient conditions are derived to guarantee quadratic stability along with a prescribed H_∞‐norm bound. Each of them can be dealt with as a linear matrix inequality (LMI) which can be tested with efficient algorithms. All the switching rules are constructively designed, and do not rely on any uncertainties.     

COMPARISON OF FLIGHT CONTROL SYSTEM DESIGN METHODS IN LANDING

Intelligent control theory usually involves the subjects of neural control and fuzzy logic control. The great potential of intelligent control in control designs has recently been realized in the literature. In this survey paper, we attempt to employ this subject and provide the reader with an overview of related topics, such as conventional, fuzzy logic‐based, neural net‐based adaptive control techniques. Practical control schemes realistically applicable in the area of control system design are introduced. The control laws are demonstrated on a three‐degree‐of‐freedom simulation with linearized aerodynamic and engine models. This paper deals the issue of aircraft landing maneuvers. Generally this part of flight needs to be strongly assisted by human pilot.     

基于区分服务感知的MPLS网络流量分配方法

服务质量（Qos）和流量工程（TE）是在当今网络中提供实时应用业务的两种重要技术。多协议标记交换（MPLS）在IP网Qos提供和TE功能实现中起了关键作用。首先介绍了区分服务感知的流量工程（DS-TE），然后提出了一种基于DS-TE的网络流量分配新方法。给出了相关的数学模型，并进行了相应的仿真，仿真结果表明使用该方法实施DS-TE时，在满足不同业务的QoS同时能较好地均衡网络负荷。