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991.
基于物联网的人性化智能家居系统研究 总被引:1,自引:0,他引:1
针对智能家居系统特点及需求,建立基于物联网的人性化智能家居系统架构模型,研发中转器、壁式智能控制终端、基于Android的智能控制终端,最后搭建整个基于物联网的人性化智能家居系统,进行远程控制及现场控制测试。该系统性能稳定、性价比高、舒适安全、实用性及可操作性强,可个性化情景模式控制,易于安装、维护及扩展。 相似文献
992.
采用Materials Studio 6.1中的Dmol3程序,程序中的数字积分是medium水平,位移收敛标准、能量和受力分别是5×10-3 A,2×10-5 au/和4×10-3 au/,利用DFT理论中的梯度校正GGAPW91方法和NDN机组计算。计算离子液体催化燃料油加氢脱硫过程的机理。通过对噻吩在离子液体酸性阴离子作用下的中间体和过渡态能量的研究,发现离子液体的阴离子不仅起到萃取作用,且在过渡态形成的过程中有促进加氢脱硫的作用,在一定的程度上起到催化剂的作用,并且活泼氢有利于噻吩加氢的进行。计算将为离子液体加氢脱硫机理提供重要的参考价值。 相似文献
993.
在分析Toshiba公司TCD1209D型CCD工作原理的基础上,分析了驱动时序的关系,详细介绍了驱动电路的设计和实现方法.用Verilog语言设计了TCD 1209D的驱动时序控制电路;选用CyclonelⅣ系列FPGA器件,使用QuartusⅡ软件对设计电路进行了功能仿真,实现了TCD1209D的高速时序驱动;在CycloneⅣ芯片平台上测试了TCD 1209D的实际输出信号.实验结果显示,CCD信号噪声较小,验证了所设计驱动电路的可行性,确定了相关双采样的时刻和位置,为小型CCD测量系统的设计提供了有益参考. 相似文献
994.
995.
针对突发通信的定时同步问题,提出一种基于正弦波形的快速定时同步算法。利用四个平均幅值点确定一条正弦曲线估计出定时误差,既能够实现4倍符号速率的定时同步,又避免了传统最大似然估计法需要进行的大量乘法运算,能够实现定时误差的快速估计。最后利用MATLAB进行Monte Carlo仿真实验,仿真结果表明新算法不仅具有低的复杂度,还具有高的估计精度。 相似文献
996.
为满足用户自定义流程的服务需求,实现敏捷BPM的业务驱动,提出一种面向用户操作的可视化流程模型。该模型采用BPM与SOA组合作为系统底层架构,并利用数据库建模进行节点编排与逻辑控制。在此基础之上,引入TWaver Flex+JSON+J2EE技术,将JSON作为数据传输格式,通过Java对象的后台处理以及Flex界面的自动布局,完成模型的图形化交互。以此构建的BPM系统,用户深度参与、动态协同,实现了流程的灵活定制与管理。河北某矿业集团的应用证实了系统的实用性和敏捷性。 相似文献
997.
Interval-valued information system is used to transform the conventional dataset into the interval-valued form. To conduct the interval-valued data mining, we conduct two investigations: (1) construct the interval-valued information system, and (2) conduct the interval-valued knowledge discovery. In constructing the interval-valued information system, we first make the paired attributes in the database discovered, and then, make them stored in the neighbour locations in a common database and regard them as ‘one’ new field. In conducting the interval-valued knowledge discovery, we utilise some related priori knowledge and regard the priori knowledge as the control objectives; and design an approximate closed-loop control mining system. On the implemented experimental platform (prototype), we conduct the corresponding experiments and compare the proposed algorithms with several typical algorithms, such as the Apriori algorithm, the FP-growth algorithm and the CLOSE+ algorithm. The experimental results show that the interval-valued information system method is more effective than the conventional algorithms in discovering interval-valued patterns. 相似文献
998.
Spectral mixture analysis for bi-sensor wetland mapping using Landsat TM and Terra MODIS data 总被引:2,自引:0,他引:2
Spatial and temporal resolution is essential for understanding the spatial and temporal characteristics and dynamics of wetland ecosystems. However, single satellite imagery with both high spatial resolution and high temporal frequency is currently unavailable. Instead, the development of a bi-sensor monitoring technique utilizing spatial details of middle-to-high resolution data and temporal details of coarse spatial resolution data is highly desirable. For the initial work on our time-series bi-sensor wetland mapping, the applicability of multiple endmember spectral mixture analysis (MESMA) using single-date bi-sensor imagery with different orbiting periods was investigated. Landsat-5 Thematic Mapper (TM) and Terra Moderate Resolution Image Spectrometer (MODIS) data were utilized in the Poyang Lake area in China and the Great Salt Lake area in the USA to examine three decisive elements in utilizing MESMA: (1) the method of optimal endmember selection; (2) the threshold between two- and three-endmember models; and (3) the treatment of shade fractions. As a result, we found that (1) the number of spectra for an endmember spectrum similar to other endmember spectra meeting the modelling restrictions of maximum and minimum land-cover fractions and root mean square error (RMSE) within a class (In_CoB), the number of spectra for an endmember spectrum similar to other endmember spectra meeting the modelling restrictions outside of a class (Out_CoB), the ratio of In_CoB to Out_CoB multiplied by the inverse number of spectra within the class (CoBI) and the endmember average RMSE (EAR) were optimal endmember selection methods for the TM maps, whereas CoBI, EAR and minimum average spectral angle (MASA) were optimal endmember selection methods for the MODIS maps; (2) the MODIS maps were more sensitive to change in the two- and three-endmember modelling thresholds than the TM maps; and (3) the addition of shade fractions to dark water fractions were an appropriate shade treatment. This research demonstrated how MESMA can be applied for multi-scale mapping of wetland ecosystems, how the difference in observation dates between the TM and MODIS data affects the agreement in land-cover fractions and how spectral similarity between dark water and shade affects the agreement in land-cover fractions. 相似文献
999.
Q. Zhang J. Wang X. Peng P. Gong P. Shi 《International journal of remote sensing》2013,34(15):3057-3078
In this article, Landsat TM images acquired during the same season from both 1984 and 1997 were analysed for urban built-up land change detection in Beijing, China, where great changes have taken place during the recent decades. To reduce the spectral confusion between urban 'built-up' and rural 'non built-up' land cover categories, we propose a new structural method based on road density combined with spectral bands for change detection. The road density represents one type of structural information while the multiple Landsat TM bands represent spectral information. Road density maps for both dates were produced using a gradient direction profile analysis (GDPA) algorithm and then integrated with spectral bands. Results from the spectral-structural postclassification comparison (SSPCC) and spectral-structural image differencing (SSID) methods were evaluated and compared with spectral-only change detection methods. The proposed SSPCC method greatly reduced spectral confusion and increased the accuracy of land cover classification compared with spectral classification, which in turn improved the change detection results. This article also shows that the SSID change detection result complemented spectral band differencing by detecting areas with greater structural changes, some of which were missed, by spectral band differencing. 相似文献
1000.
N. J. Austin J. P. Muller L. Gong J. Zhang 《International journal of remote sensing》2013,34(8):2983-3011
The near-completion of the Three Gorges Dam has led to the creation of a narrow reservoir that, when completed in 2009, will stretch over 660 km upstream and result in the displacement of approximately 1.2 million people. This reservoir will drown more than 100 towns, some of which have already been lost due to the rising waters, and result in a significant change in land use. New urban areas have been constructed at higher elevations to avoid the rising water but it is feared that some of these settlements may now be exposed to a greater risk of landslides due to slope failure. A geographic information system (GIS) consisting of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Landsat Thematic Mapper (TM), and Environmental Satellite-Advanced Synthetic Aperture Radar (ENVISAT-ASAR) data has been created and used to monitor the urban changes from before the Dam's construction to the present day as well as changes in landslide susceptibility. To perform this analysis, a new 30 m high-resolution digital elevation model (DEM) was derived by combining an ASTER and Shuttle Radar Topography Mission (SRTM) DEM. Fieldwork was carried out along the Yangtze River, where the urban boundaries were field-checked using GPS to navigate to the satellite-derived checkpoints. The results show that a majority of the new urban areas are in fact located on shallow slopes, but are often positioned below steep slopes, which could pose a future threat of landslide risk to the inhabitants of the new towns. 相似文献