一种优化的多源遥感影像高精度配准方法

探讨了一种优化的多源遥感影像的高精度配准算法.利用梯度算子结合Forstner算子快速提取特征点,同时采用基于熵的格网技术控制特征点的分布均匀度,在少量准确控制点的基础上以不变矩相似度量为匹配准则,采用整体松弛法匹配策略快速配准得到同名点,并利用二次多项式模型来剔除误配准点.结果表明,该方法配准速度快,得到的同名点精度高,分布均匀,可以满足遥感影像的融合与快速更新等后续处理的要求.     

关于蒙特卡罗方法在高等数学中的应用

运用蒙特卡罗方法并结合Matlab软件,通过举例讨论了高数中常见的几类数学问题：数值积分、函数最值的求解、一元函数根的求解以及规划问题的求解。     

考虑钢筋作用的块体单元法计算模型

依据块体单元法的理论和计算模型,提出了考虑钢筋作用效应的块体单元法计算模型.在此模型中,钢筋被简化为线弹性体,选取标距段内的钢筋为基本钢筋单元,通过分析钢筋在块体单元中的受力特性,建立起钢筋的应力模式,然后得到其内力势能表达,将此势能并入结构的整体势能中,从而实现钢筋单元和块体单元的结合.算例结果表明,该模型合理且可行.     

电控汽油发动机故障模拟试验

在自行开发的电控汽油发动机故障模拟试验台上,完成了主要传感器的故障模拟试验,对比研究了相关故障对发动机动力性、经济性和排放等性能的影响.试验结果表明:空气流量信号丢失后,中小负荷时混合气过浓,从而使比油耗上升,HC和CO排放增加,NOx排放减小,而大负荷时,空气流量信号的有无对发动机性能影响较小;节气门位置传感器的怠速信号丢失后,发动机运转不稳;全负荷信号丢失后,满负荷时混合气没有加浓,功率下降,但比油耗略有减小,CO和HC排放降低,NOx排放升高;爆震信号丢失后,点火提前角减小,功率下降,比油耗升高,HC和NOx排放减小,CO排放基本不变;冷却液温度传感器信号丢失后,冷启动时混合气没有加浓,发动机冷启动困难.     

Newly discovered Palaeolithic artefacts from loess deposits and their ages in Lantian,central China

Eight new Palaeolithic open-air sites were identified and 770 stone artefacts were collected from 2009 to 2011 in the Lantian area of the Bahe River valley, central China. Because the famous Homo erectus fossils were unearthed at the Gongwangling and Chenjiawo localities, and more than 30 Palaeolithic open-air sites were investigated in the 1960s in this region, the catchment of Bahe River is regarded as one of the most important hominin sites from the late early Pleistocene to the middle Pleistocene. These eight newly discovered open-air sites are located at the second(n = 6), third(n = 1) or higher terraces(n = 1) of the Bahe River. The Diaozhai section on the second terrace was sampled in detail. Two samples were collected for optically stimulated luminescence dating(OSL). The OSL results suggest that a buried lithic artefact layer at the Diaozhai site spans approximately 70–30 ka. The lithic assemblage analysis suggests that the stone artefacts were made of local pebbles/cobbles such as greywacke, quartz, sandstone and igneous rocks. The main percussion techniques that were used were direct hard hammer percussion and bi-polar techniques. The lithic artefacts comprise hammer stones, cores, flakes, retouched tools and flaking debris. Acheulian-type large cutting tools(LCTs) such as hand-axes, picks and cleavers were indentified in the Lantian region as well. This is the first time Acheulian-type LCTs from the late Pleistocene have been identified in this region. This study distinguishes age gaps between Western world and East Asian Acheulian-type tools.     

电梯服务系统的排队模型

运用排队论理论建立了电梯服务系统的最少服务一个顾客最多服务γ个顾客的成批服务M/M/1排队模型,并给出了γ为随机变量时电梯服务系统的一些参数指标.     

基于非线性整数规划的平均血糖波动幅度自动计算算法研究

平均血糖波动幅度(MAGE)是评估血糖波动的"金标准",但目前基于动态血糖监测数据的MAGE参数主要依靠人工计算,耗时、准确性低;为此国内外推出了几种MAGE自动计算方法;由于这些方法缺乏数学理论的支撑,使得计算结果的准确性受到临床的质疑,从而影响它们的广泛应用。因此,研究以MAGE定义为基础,提出了一种非线性整数规划数学模型;并应用差分进化算法求解的自动计算算法。该算法与人工方法的计算结果对比,验证显著相关,且具有较好的一致性;并与现有的一些MAGE自动计算方法的计算结果进行了统计比较分析,结果证明研究的算法可以取代人工计算方法进行MAGE自动计算。     

小流量工况下叶尖弯曲对间隙流动影响的数值研究

为研究叶片叶尖弯曲对间隙流动的影响情况,采用数值模拟方法,研究了不同叶尖弯曲参数(弯曲方向、弯高、弯角)对跨声速压气机动叶在小流量工况条件下的间隙流动的影响,研究对象为美国国家航空航天局(National Aeronautics and Space Administration,NASA)Rotor37跨声速压气机转子...     

基于灰色定权聚类模型的公路边坡水毁风险等级评价

针对公路边坡水毁风险等级评价因素的灰色性和模糊性问题,提出一种基于灰色定权聚类模型的风险等级评价方法.以福建省泉州市德化县农村公路边坡水毁为例,基于现场调查和数据的统计分析,选取了10个主要影响因子,利用因子分析法计算每个水毁因子的权重;将公路边坡水毁风险划分为四个等级,构建三角白化权函数,建立评价指标体系,利用灰色定权聚类模型定量计算公路边坡水毁风险等级及抗水毁能力,计算结果与现场调查相符合.灰色定权聚类评价模型减少了风险评价过程中主观因素的影响,研究结果对类似的公路边坡水毁风险评估、提升农村公路抗水毁风险能力具有理论及实际意义.