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91.
Impact of DEM accuracy and resolution on topographic indices 总被引:1,自引:0,他引:1
Topography is an important land-surface characteristic that affects most aspects of the water balance in a catchment, including the generation of surface and sub-surface runoff; the flow paths followed by water as it moves down and through hillslopes and the rate of water movement. All of the spatially explicit fully distributed hydraulic and hydrological models use topography (represented by the DEM of the area modelled) to derive bathymetry. DEM is also used to derive some other key information critical in fully distributed hydraulic and hydrological models.With high-resolution DEMs such as LiDAR (Light Detection and Ranging) becoming more readily available and also with the advancements in computing facilities which can handle these large data sets, there is a need to quantify the impact of using different resolution DEMs (e.g. 1 m against 10 m or 25 m) on hydrologically important variables and the loss of accuracy and reliability of the results as we move from high resolution to coarser resolution.The results from statistical analysis carried out to compare field survey elevations with the LiDAR DEM-derived elevations, show that there are small differences between the two data sets but LiDAR DEM is a reasonably good representation of the actual ground surface compared to other commonly used DEMs derived from contour maps.The results from the analysis clearly show that the accuracy and resolution of the input DEM have serious implications on the values of the hydrologically important spatial indices derived from the DEM. The result also indicates that the loss of details by re-sampling the higher resolution DEM to coarser resolution are much less compared to the details captured in the commonly available coarse resolution DEM derived from contour maps. Topographic indices based on contour derived DEMs should be used with caution and where available, the higher resolution DEM should be used instead of the coarse resolution one. 相似文献
92.
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
93.
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
94.
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
95.
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
96.
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
97.
98.
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
99.
针对近年来飞机含80C186处理器电路板修理现状,为掌握该系列板件的修理能力,迫切需要开展其软件测试技术研究.从封装、类型以及时序分析角度,在对80C186处理器进行系统阐述基础上,设计并研制一块基于80C186处理器的多功能(包括串口通信、并口检测以及定时计数功能)实验板,给出该板的硬件电路图与软件流程框图,并基于汇编语言在QTH-2008PCI开发环境下进行功能调试,实验结果表明其有效性.所做的含80C186处理器的正向设计与软件编程研究工作对于逆向修理含80C186处理器飞机电路板板件有很大帮助. 相似文献
100.