高原驻训航材有寿件需求预测研究

高原驻训航材保障中,有寿件重要度较高,部队必须携带足够的备件数量来满足任务需要.根据高原驻训条件下航材有寿件需求特点,将有寿件的需求分为到寿更换需求和随机故障消耗产生的需求两部分,分别用数学公式和仿真计算方法进行预测,再将两者结果相加为总需求量.通过实例分析验证,采用工程测算方法可以避免逐一分析器材寿命的繁杂,而单独考...     

激光频率调制线型分析

在激光频率调制的理论分析中,一般采用正弦波调制、正弦波解调,而没有讨论调制和解调的其它情况。本文主要分析了Guass线型吸收的情况下,锯齿波调制、方波解调的一次、二次谐波相检结果和三角波调制、方波解调的一次、二次谐波相检结果,以及调制深度对信号谱形和信号强度的影响。我们发现,在锯齿波调制、方波解调情况下,一次、二次谐波谱形和正弦波调制情况区别很大;但在三角波调制、方波解调情况下,可以获得和正弦波调制、正弦波解市场相似的结论。另外,不同的调制深度对输出的调制谱形也有重要的影响。我们还用甲烷的可调谐 红外光调制吸收光谱实验验证了理论分析结果。最终得到结论：频率调制谱的信号谱形及信号强度与调制波形、解调波形和调制深度均有关系。     

神经网络汛期降水短期气候预测模型

用1960-2005年每年5-9月安徽宣城7县(市)平均降水量作为预报对象,在对应降水前期逐月74项大气环流特征量资料、500hPa月平均高度场和月平均海温场资料中选取因子.采用主分量分析方法构造网络学习矩阵,降低矩阵维数,提高网络预测模型泛化性能.建立的神经网络汛期降水短期气候预测模型对历年样本拟合精度高,试报效果较好,可在气候预测业务中使用.     

灰色系统理论在粮食产量预测中的应用

应用灰色系统理论的基本原理,建立灰色预测模型,并以2010-2015年甘肃省的粮食产量为统计资料,运用GM(1,1)模型进行预测,取得了较好的预测效果.     

Kalman滤波在气象预报中的应用

本文讨论了 Kalm an滤波算法及其在气象预报中的应用 ,并对烟台 11市、区、县的日最高、最低气温预报的结果进行了分析     

改进欧拉算法在油液光谱分析趋势预测中的应用

基于原子发射光谱油液分析是大型机械设备磨损状态监测与故障诊断的重要技术,由于灰预测理论在趋势预测方面具有明显的优势,文章利用油液原子发射光谱分析结果,结合灰预测理论,建立了某综合传动油液中金属元素Fe趋势变化的灰预测模型。在模型参数辨识求解上首次引入了改进欧拉算法,解决了避免原灰预测模型在实际应用过程中出现的预测结果主要依赖于第一个实测值的问题,使得预测结果更准确。将该算法结合原子发射光谱分析Fe元素浓度的阈值制定,有效地捕捉到综合传动发生故障的征兆信息,及时采取措施防止综合传动的故障,具有很好的推广应用价值。     

Boosting the advantages of biosensors: Niche applicability and fitness for environmental purpose

Environmental assessments rely on data derived from metrological schemes in order to draw in due detail the state of the ecosystems. The reliability of the data and the cost-effectiveness of the scheme become critical, especially if the ultimate goal involves decision making and policy development. Biosensor platforms provide the versatility required for integrating environmental, metrological and operational parameters at the design phase. The pertinency and the opportunity for environmental biosensing is apparent, although not seized appropriately with only a few environmental biosensors in the market. This study is based on a technology forecasting approach using bibliometric data to trace the dynamics of the science base and content analysis to identify the drawbacks of the technology base. The results are compared with market forecasts in an effort to align research dynamics with market opportunities. A number of key findings emerged, such as the increase in networking and the establishment of a multi-disciplinarity trend, as well as a shifting of research scope towards ready-to-market designing. Notwithstanding, a renewed interest of the physical chemistry sector has been identified herein, indicating necessary revisions of the science-base, adding a critical parameter in the uncertainty of trajectories.     

零售物价总指数的相关因素分析及预测的数学建模

本文对我国测量通货膨胀的主要指标全国零售物价总指数进行了相关因素分析，并在此基础上建立了零售物价总指数预测的数学模型．     

Fourier-Laplace analysis of the multigrid waveform relaxation method for hyperbolic equations

The multigrid waveform relaxation (WR) algorithm has been fairly studied and implemented for parabolic equations. It has been found that the performance of the multigrid WR method for a parabolic equation is practically the same as that of multigrid iteration for the associated steady state elliptic equation. However, the properties of the multigrid WR method for hyperbolic problems are relatively unknown. This paper studies the multigrid acceleration to the WR iteration for hyperbolic problems, with a focus on the convergence comparison between the multigrid WR iteration and the multigrid iteration for the corresponding steady state equations. Using a Fourier-Laplace analysis in two case studies, it is found that the multigrid performance on hyperbolic problems no longer shares the close resemblance in convergence factors between the WR iteration for parabolic equations and the iteration for the associated steady state equations.     

Decision and forecast horizons,agreeable plans,and the maximum principle for infinite horizon control problems

This paper establishes a link between the concepts of optimality used in economic theory for infinite horizon planning models, and the concepts of decision and forecast horizons used in several areas of Management Science. It is shown that decision and forecast horizons induce an alternate definition of optimality which is stronger than the concept of ‘agreeable plan’ proposed by Hammond. All concepts of optimality share a common property, namely a Principle of Optimality. In an optimal control framework this implies that the maximum principle will be a necessary condition for optimality according to any of these definitions.