A modeling method of the support vector machine combined with matrix optics is considered; a complete new measurement model for double-four quadrant photoelectric detector is built. According to the analysis of the re...A modeling method of the support vector machine combined with matrix optics is considered; a complete new measurement model for double-four quadrant photoelectric detector is built. According to the analysis of the received light spot size and its motion with the changes of the defocusing amount of detector photosensitive surface and the detector position attitude in the optical path, a mathematic expression of photoelectrical conversion is given, which can be applicable to random setting position of the detector at any time. Based on least square support vector machine (LS SVM), the mapping relationship among the output signal linear characteristic parameters (zero neighborhood gradient and intercept), the defocusing amount of the detector and the installation position attitude angle is established. Thus, the multiple dimensional high accuracy measuring and adjusting control system can be left out, and adaptive measurement of the detector parameters can be realized. Compared with existed measurement model and method, the presented model has the advantages of more clear physical meaning, closer to work mechanism of detector, acquiring more complete sample data and wiping out the dead spots or bad spots in measurement. And the accuracy of displacement measurement is increased to 3?μm. At the same time, this measurement mode provides a technical shortcut for three-dimensional small angle measurement.展开更多
人类活动是引起生态系统服务价值(Ecosystem Service Value,ESV)变化的重要原因,分析二者的时空演变特征并划定生态分区对实现区域可持续发展意义重大。以长江经济带为例,以2000、2010、2020年3期土地利用数据为基础数据,构建综合指标...人类活动是引起生态系统服务价值(Ecosystem Service Value,ESV)变化的重要原因,分析二者的时空演变特征并划定生态分区对实现区域可持续发展意义重大。以长江经济带为例,以2000、2010、2020年3期土地利用数据为基础数据,构建综合指标体系量化人类活动强度(Human Activity Intensity,HAI)、采用当量因子法计算生态系统服务价值,基于二者关系运用四象限模型划分生态质量分区。结果表明:(1)HAI以低强度和较低强度为主,空间分异特征显著。高强度区域成片分布在长江下游地区以及各省的省会城市,其范围逐年扩张。低强度区域主要分布在研究区中部、东南以及西北区域,面积不断扩大。(2)20 a间长江经济带ESV整体呈下降趋势,共减少409.75亿元;空间上,长江经济带上游地区较低值区分布最为广泛,其次是中值和较高值区;中游地区以较高值区为主,ESV大致呈“西高东低”的空间分布格局,下游地区ESV空间分布呈现“北低南高”的格局。(3)研究区生态质量整体较好,95%的县域分布在生态质量为优秀、一般和良好的区域,2000~2020年生态质量有所下降。研究可为区域生态系统的精细化管理以及生态环境的保护与修复提供参考依据。展开更多
文摘A modeling method of the support vector machine combined with matrix optics is considered; a complete new measurement model for double-four quadrant photoelectric detector is built. According to the analysis of the received light spot size and its motion with the changes of the defocusing amount of detector photosensitive surface and the detector position attitude in the optical path, a mathematic expression of photoelectrical conversion is given, which can be applicable to random setting position of the detector at any time. Based on least square support vector machine (LS SVM), the mapping relationship among the output signal linear characteristic parameters (zero neighborhood gradient and intercept), the defocusing amount of the detector and the installation position attitude angle is established. Thus, the multiple dimensional high accuracy measuring and adjusting control system can be left out, and adaptive measurement of the detector parameters can be realized. Compared with existed measurement model and method, the presented model has the advantages of more clear physical meaning, closer to work mechanism of detector, acquiring more complete sample data and wiping out the dead spots or bad spots in measurement. And the accuracy of displacement measurement is increased to 3?μm. At the same time, this measurement mode provides a technical shortcut for three-dimensional small angle measurement.
