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151.
In this paper, the dynamic behaviors of a class of neural networks with time-varying delays are investigated. Some less weak
sufficient conditions based on p-norm and ∞-norm are obtained to guarantee the existence, uniqueness of the equilibrium point for the addressed neural networks
without impulsive control by applying homeomorphism theory. And then, by utilizing inequality technique, Lyapunov functional
method and the analysis method, some new and useful criteria of the globally exponential stability with respect to the equilibrium
point under impulsive control we assumed are derived based on p-norm and ∞-norm, respectively. Finally, an example with simulation is given to show the effectiveness of the obtained results. 相似文献
152.
Zhu Teng Jeong-Hyun Kim Dong-Joong Kang 《International Journal of Control, Automation and Systems》2010,8(4):822-830
In this paper, a novel method of real-time fire detection based on HMMs is presented. First, we present an analysis of fire characteristics that provides evidence supporting the use of HMMs to detect fire; second, we propose an algorithm for detecting candidate fire pixels that entails the detection of moving pixels, fire-color inspection, and pixels clustering. The main contribution of this paper is the establishment and application of a hidden Markov fire model by combining the state transition between fire and non-fire with fire motion information to reduce data redundancy. The final decision is based on this model which includes training and application; the training provides parameters for the HMM application. The experimental results show that the method provides both a high detection rate and a low false alarm rate. Furthermore, real-time detection has been effectively realized via the learned parameters of the HMM, since the most time-consuming components such as HMM training are performed off-line. 相似文献
153.
从系统性能,运行效率和经济效益等方面出发,设计出一种低功耗的多路温度采集与实时检测系统,既可为供热部门提供实际温度参数,合理调度锅炉运行时间,降低能耗;又可以为监管部门提供可靠的供热质量信息,方便协调和管理,化解供需的矛盾。具有较好的经济效益和社会效益。 相似文献
154.
信息网络化的社会,消防报警设备的网络化是大势所趋。为了不浪费现行的消防联动设备资源,研究设计出一套基于ARM的硬件平台,集成了无线通信模块和图像采集模块。采用低成本硬件,达到系统功能要求。 相似文献
155.
路径规划算法是车载导航的核心问题。充分利用启发式搜索具有方向性的启发信息,对A*算法进行改进,采用双向的A*算法来避免过多的节点搜索和搜索过界,不能得到正确结果的问题。同时,为了适合嵌入式平台的特殊环境,采用数据分层,搜索过程升层的方法,充分利用内存资源,减少外存I/O的工作量。并且结合上述策略,给出了改进的算法伪代码流程并对改进的A*算法的进行验证。 相似文献
156.
ETM+和ASTER数据在遥感信息提取中的对比研究 总被引:3,自引:0,他引:3
遥感蚀变信息提取是找矿的一个重要技术手段。本文选择位于秘鲁南部阿雷基帕(AREQUIPA)省境内的萨卡纳(CERCANA)和伊卡(ICA)省境内的Moarcona铁矿区作为本文的两个研究区,从分析地物光谱出发,利用ETM+和ASTER卫星影像数据,通过主成份分析法和比值分析法分别对两个研究区进行泥化蚀变信息提取和铁染蚀变信息提取,并对两者的提取结果进行对比分析。最后结果表明,相较于ETM+数据,ASTER数据在矿化蚀变信息的提取方面具有更大的优势。 相似文献
157.
Kai Ming Ting Jonathan R. Wells Swee Chuan Tan Shyh Wei Teng Geoffrey I. Webb 《Machine Learning》2011,82(3):375-397
This paper introduces a new ensemble approach, Feature-Subspace Aggregating (Feating), which builds local models instead of
global models. Feating is a generic ensemble approach that can enhance the predictive performance of both stable and unstable
learners. In contrast, most existing ensemble approaches can improve the predictive performance of unstable learners only.
Our analysis shows that the new approach reduces the execution time to generate a model in an ensemble through an increased
level of localisation in Feating. Our empirical evaluation shows that Feating performs significantly better than Boosting,
Random Subspace and Bagging in terms of predictive accuracy, when a stable learner SVM is used as the base learner. The speed
up achieved by Feating makes feasible SVM ensembles that would otherwise be infeasible for large data sets. When SVM is the
preferred base learner, we show that Feating SVM performs better than Boosting decision trees and Random Forests. We further
demonstrate that Feating also substantially reduces the error of another stable learner, k-nearest neighbour, and an unstable
learner, decision tree. 相似文献
158.
The adhesion, friction, wear in micro system or MEMS is more significant than those in macro system. The levitation or suspension
technique is one of the effective techniques to eliminate the adhesion, friction, wear caused by the surfaces contact. The
electromagnetic levitation micromotor with stators embedded (ELMSE) is a kind electromagnetic eddy current levitation system,
which has special structure including the double sided stator and the hollow annular rotor. Different from the electromagnetic
eddy current levitation system with single sided stator, ELMSE has good stability in the vertical and lateral directions.
Using the finite element method, the levitation characteristics and lateral stability characteristics are analyzed. The influence
of structural parameters and electric parameters on the vertical stiffness and the lateral stiffness has been analyzed and
optimized in the paper. The analysis result of the paper provides theoretical reference for the optimal design of ELMSE. 相似文献
159.
160.
In this paper, two delayed SEIR epidemic models with continuous and impulsive vaccination and saturating incidence are investigated. The dynamical behaviors of the disease are analyzed. For continuous vaccination, we obtain a basic reproductive number R1 and prove that if R1≤1 then the disease-free equilibrium is globally attractive and if R1>1 then the disease is permanent by using the Lyapunov functional method. For impulsive vaccination, we obtain two thresholds R∗ and R∗ and prove that if R∗<1 then the disease-free periodic solution is globally attractive and if R∗>1 then the disease is permanent by using the comparison theorem of impulsive differential equation and the Lyapunov functional method. Lastly, we compared the effects of two vaccination strategies. 相似文献