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971.
An Efficient Path Planning and Control Algorithm for RUAV’s in Unknown and Cluttered Environments 总被引:1,自引:0,他引:1
Kwangjin Yang Seng Keat Gan Salah Sukkarieh 《Journal of Intelligent and Robotic Systems》2010,57(1-4):101-122
This paper presents an efficient planning and execution algorithm for the navigation of an autonomous rotary wing UAV (RUAV) manoeuvering in an unknown and cluttered environment. A Rapidly-exploring Random Tree (RRT) variant is used for the generation of a collision free path and linear Model Predictive Control(MPC) is applied to follow this path. The guidance errors are mapped to the states of the linear MPC structure by using the nonlinear kinematic equations. The proposed path planning algorithm considers the run time of the planning stage explicitly and generates a continuous curvature path whenever replanning occurs. Simulation results show that the RUAV with the proposed methodology successfully achieves autonomous navigation regardless of its lack of prior information about the environment. 相似文献
972.
973.
A combination of soft lithography and lift-off processing is presented for the fabrication of sulfonated polyaniline (SPAN) microstructures. A soft lithography based micromolding process was used to pattern sacrificial layers using a thermoplastic polymer. SPAN was then polymerized in situ to coat the patterned substrate. The sacrificial layer was removed by lift-off in an organic solvent, leaving the patterned SPAN on the substrate. This process was performed on several rigid and flexible substrates including glass, silicon, and polyimide. The film thickness and roughness were measured as a function of reaction time using atomic force microscopy. Patterns were also imaged using scanning electron microscopy. This process provides a cost effective and versatile method of patterning SPAN and has potential applications in a number of conducting polymer devices. 相似文献
974.
Real-time removal of ocular artifacts from EEG based on independent component analysis and manifold learning 总被引:1,自引:1,他引:0
Junfeng Gao Pan Lin Yong Yang Pei Wang Chongxun Zheng 《Neural computing & applications》2010,19(8):1217-1226
Frequent occurrence of ocular artifacts leads to serious problems in interpreting and analyzing the electroencephalogram (EEG).
In the present paper, a novel and robust technique is proposed to eliminate ocular artifacts from EEG signals in real time.
Independent Component Analysis (ICA) is used to decompose EEG signals. The features of topography and power spectral density
of those components are extracted. Moreover, we introduce manifold learning algorithm, a recently popular dimensionality reduction
technique, to reduce the dimensionality of initial features, and then those new features are fed to a classifier to identify
ocular artifacts components. A k-nearest neighbor classifier is adopted to classify components because classification results
show that manifold learning with the nearest neighbor algorithm works best. Finally, the artifact removal method proposed
here is evaluated by the comparisons of EEG data before and after artifact removal. The results indicate that the method proposed
could remove ocular artifacts effectively from EEG signals with little distortion of the underlying brain signals and be satisfied
the real-time application. 相似文献
975.
The fluid, urgent nature of crises requires flexible, responsive information sharing. Recent studies show, however, that in business catastrophes and other kinds of crises conventional access control mechanisms favor security over flexibility. Our work addresses these seemingly contradictory needs for security and flexibility and designs a trust inference model based on fuzzy logic, a model that can be used with pervasive computing technologies using sensors and mobile devices. Drawing upon research on trust, we design a trust inference model using attributes of affiliation, task performance, and urgency; apply the model to a known crisis; discuss implementation issues; and explore issues for further research. This article is dedicated to Alan Jarman, a founding influence in the Journal of Contingencies and Crisis Management who died in Canberra 15 July 2010. Alan's quantitative, engineering background and his long standing commitment to improving crisis decision making prompted him to encourage our applying fuzzy logic to crisis information sharing. We are grateful for Alan's encouragement and advice. 相似文献
977.
该文以家庭电器和灯光智能化控制等方面的需求为例,介绍一种以JZ863为数据传输模块,基于89C2051单片机设计的无线遥控电路设计方案。与编码电路芯片设计的遥控电路相比,外围电路简单,功耗低,编程容易,可靠性高,扩展功能强。 相似文献
978.
一种高性能网络游戏服务器架构设计 总被引:1,自引:0,他引:1
杨玲 《网络安全技术与应用》2010,(4):59-61
网络游戏一般采用C/S结构,服务器架构设计是成功开发一款网络游戏的关键,本文对高性能网络游戏服务器架构设计进行了深入地研究。网络游戏服务器的物理结构一般分成区和组,一个区会包括多组服务器,本文设计出的服务器组架构包括LoginGate、LoginServer、GameGate、GameServer、DBServer和MServer等服务器。 相似文献
979.
改进的Gabor滤波算法在指纹识别中的应用 总被引:1,自引:0,他引:1
指纹自动识别系统中图像的处理和匹配算法在系统的设计中起了尤为重要的作用,本文对Gabor滤波算法进行了简化,同时引入了HGF(Half Gabor Filter)对指纹图像进行了增强处理。实验结果表明经过这种改进的Gabor滤波算法提高了图像的处理速度,并很好的保留纹线的关键信息。 相似文献
980.
本文在JFreeChart的基础上,通过设计模式的引入,提出了一种更加方便的基于JFreeChart绘制Web统计图表的设计与实现,这让开发人员不必再过多的关注JFreeChart API,而能抽出更多的时间和精力关注业务逻辑。 相似文献