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201.
Fire detection is an important task in many applications. Smoke and flame are two essential symbols of fire in images. In this paper, we propose an algorithm to detect smoke and flame simultaneously for color dynamic video sequences obtained from a stationary camera in open space. Motion is a common feature of smoke and flame and usually has been used at the beginning for extraction from a current frame of candidate areas. The adaptive background subtraction has been utilized at a stage of moving detection. In addition, the optical flow-based movement estimation has been applied to identify a chaotic motion. With the spatial and temporal wavelet analysis, Weber contrast analysis and color segmentation, we achieved moving blobs classification. Real video surveillance sequences from publicly available datasets have been used for smoke detection with the utilization of our algorithm. We also have conducted a set of experiments. Experiments results have shown that our algorithm can achieve higher detection rate of 87% for smoke and 92% for flame.  相似文献   
202.
we present a novel polarimetric synthetic aperture radar (PolSAR) image compression scheme. PolSAR data contains lots of similar redundancies in single-channel and massively correlation between polarimetric channels. So these features make it difficult to represent PolSAR data efficiently. In this paper, discrete cosine transform (DCT) is adopted to remove redundancies between polarimetric channels, simple but quite efficient in improving compressibility. Sparse K-singular value decomposition (K-SVD) dictionary learning algorithm is utilized to remove redundancies within each channel image. Double sparsity scheme will be able to achieve fast convergence and low representation error by using a small number of sparsity dictionary elements, which is beneficial for the task of PolSAR image compression. Experimental results demonstrate that both numerical evaluation indicators and visual effect of reconstructed images outperform other methods, such as SPIHT, JPEG2000, and offline method.  相似文献   
203.
The global skyline, as an important variant of the skyline, has been widely applied in multi-criteria decision making, business planning and data mining. In this paper, we extend our early work and propose the maintenance methods to process the subspace global skyline (SGS) queries in dynamic databases. In the previous work, we proposed the index structure RB-tree, which can effectively manage the data to accelerate the subspace global skyline calculation. Also, the basic single SGS algorithm based on RB-tree (SSRB) and the optimized single SGS algorithm (OSSRB) were proposed to process a single SGS query. In addition, the multiple SGS algorithm (MSRB) was proposed to calculate multiple SGS queries by sharing the scan spaces of different queries. In this paper, we design some data structures and propose the maintenance approaches of SSRB, OSSRB and MSRB to cope with updates that happen to data sets. Thus our extended algorithms can be adopted for dynamic data sets. Finally, the experimental results show that the proposed algorithms OSSRB and MSRB have good performance to process SGS queries and they can be easily maintained with dynamic datasets.  相似文献   
204.
采用步进频域能量检测法可以提高在软件无线电平台的频谱感知的带宽范围,但能量检测法易受噪声不确定性的影响,而信号采样自相关检测法对噪声不确定性有很好的鲁棒性。为进一步提高软件无线电的检测性能,提出了基于信号采样自相关的步进宽带频谱感知方法。首先阐述了信号采样自相关检测的原理,然后对基于该原理的步进宽带检测方法的流程进行了分析,最后利用MATLAB软件仿真其检测性能。仿真结果表明,在信噪比(Signal-noise-ratio, SNR)不同的情况下,基于信号采样自相关的步进宽带频谱检测方法能达到所要求的检测性能。此 外,为了兼顾频谱感知的检测速度和频带带宽分辨率之间的关系,进一步提出了在原本固定步进值的步进宽带信号采样自相关的频谱感知方法中采用可变步进值的两阶段检测方法,该方法可 以获得较高的频带带宽检测分辨率和较短的检测时间。  相似文献   
205.
A considerable part of the literature on fuzzy sets is devoted to the field of fuzzy control system. In this paper, an alternative control system is introduced to describe a dynamic system with fuzzy white noise. In order to find optimal ways to control such a system, fuzzy optimal control theory is further developed. Specifically, a linear quadratic model is formulated and solved as a fuzzy optimal control problem. The formulation and solution of this model provide an economic interpretation of a production planning model both in the finite horizon and in the infinite horizon.  相似文献   
206.
Many decision-makers in industry, government and academia routinely make decisions whose outcome depends on the evolution of software technology trends. Even though the stakes of these decisions are usually very high, decision makers routinely depend on expert opinions and qualitative assessments to model the evolution of software technology; both of these sources of decision-making information are subjective, are based on opinions rather than facts, and are prone to error. In this paper, we report on our ongoing work to build quantitative models of the evolution of software technology trends. In particular, we discuss how we took specific evolutionary models and merged them into a single (general-purpose) model. The original specific models are derived empirically using statistical methods on trend data we had collected over several years, and have been validated individually; in this paper we further validate the generic (general-purpose) model.  相似文献   
207.
基于卟啉阵列传感器和毒气接触发生化学反应导致其色谱变化的“指纹”特性原理,提出了一种以嵌入式ARM9 S3C2440A为核心、以Linux为操作系统、QT/Embedded为开发工具并利用卟啉化学传感器的痕量毒气检测装置.阐述了系统总体设计,实现了卟啉传感阵列光谱信号采集、信号处理、反应环境监控等主要功能模块及控制软件...  相似文献   
208.
描述了一种基于DSP、CPLD及计算机串口通信,针对薄带传输过程中出现的跑偏问题的电磁纠偏数字控制系统,并在理论分析基础上通过实验验证了该系统运行可靠、纠偏控制精度高。为电磁纠偏辊的进一步发展奠定基础。  相似文献   
209.
边缘图像连通区域标记的算法研究和SoPC实现   总被引:1,自引:0,他引:1  
针对二值边缘图像目标点较少的特点,提出了基于目标像素邻域的8方向生长区域标记算法.该算法充分利用了边缘图像的走向信息,提高了搜索效率,降低了堆栈空间消耗,消除了邻域反复扫描问题.  相似文献   
210.
基于2SC0108T的IGBT驱动器设计   总被引:1,自引:1,他引:0  
针对IGBT驱动电路复杂且保护功能不尽完善的问题,设计了一个基于2SC0108T的即插即用型IGBT驱动器,以及相应的前级驱动电路、后级功率驱动电路和故障报警电路.该驱动器具有直接模式和半桥模式、驱动信号硬件互锁、硬件死区时间可调节、IGBT过流及短路保护、驱动电源过欠压监控和易于安装的特点.结合英飞凌EconoDUA...  相似文献   
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