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1.
Spectral Neugebauer model is widely used for spectral reflectance prediction during printer characterization. However, several factors reduce the predication precision. Thus, an improved cellular Yule-Nielson spectral Neugebauer (CYNSN) model is proposed, which modifies the traditional spectral Neugebauer model in three main aspects: (1) First, in order to adjust the nonlinearities between the predicated and measured spectral reflectance, an iteratively calculated Yule-Nielson exponent is added to the reflectance values within the Neugebauer equations. (2) Second, the quantity of Neugebauer primaries is increased by dividing the CMY colorant space into 43 uniform cellular subdomains. (3) Third, the mapping functions are developed to map the area coverages' theoretical values to their effective values within the subdomains, and the mapped values highly improve the matching degree of the predicated and measured reflectance values. In the experiment, four related spectral Neugebauer models are employed during printer characterization, which are the traditional spectral Neugebauer model, Yule-Nielson spectral Neugebauer (YNSN) model, traditional CYNSN model, and the modified CYNSN model, respectively. And the experimental results show the modified CYNSN model yields a significant improvement over the other spectral Neugebauer models, by comparing the characterization errors in the form of colorimetry and spectroscopy. 相似文献
2.
超导磁体等效材料参数的有限元预测 总被引:2,自引:0,他引:2
HT—7U超导托卡马克装置中纵场超导磁体是由多种材料组成的且具有周期性分布的大型复杂的重要结构,对其宏观等效材料参数的准确掌握在其结构设计阶段是十分重要的。本文着重介绍了利用小参数展开的渐近均匀化方法对其进行等效处理的过程,并采用有限元方法预测出其等效弹性模量与热膨胀系数等,这些都为纵场磁体结构的力学计算与传热分析提供了必要的参数。 相似文献
3.
Mingzhong Li Chenwei Liu Chen Liang Jibin Li 《Journal of Dispersion Science and Technology》2014,35(3):397-402
In order to increase the present understanding of bimodal emulsion drop size distributions, systematic series of experiments have been carried out to investigate the effects of formulation variables on bimodal drop size distributions, and probability distribution functions were proposed to analyze the distribution. The results show that, the span of the drop size and Sauter mean diameter become larger when the dispersed phase volume fraction becomes higher and rotor speed becomes lower; the Frechet function represents the experimental data satisfactorily. The prediction model of Sauter mean diameter established by combining the prediction theory of the maximum stable drop diameter and experimental analysis results can fit the experimental data well. 相似文献
4.
In this paper, a special bending fatigue experiment was firstly performed to investigate the fatigue behavior of polyethylene methacrylate in adhesive assembly. Fatigue lifetime property (S–N curve) was obtained. Finite element calculations on the whole structures also gave the same results with the testing. Based on the experimental data and finite element analysis, a local stress law of predicting bending fatigue lifetime was put forward. The predication lifetime for the polyethylene methacrylate agreed well with the experimental results. Following the strain energy density (SED) criterion was applied to predict the crack initiation and growth path of the adhesive assembly. The predicted results were in good agreement with the optical microscopy (OM) failure image of the failure specimen. SEM image of fracture further showed that there were lots of parallel fatigue lines with perpendicularity to the direction of crack, and an obvious boundary from the crack propagation failure to final brittle fracture. 相似文献
5.
销售量预测的REM-GM(1,1)模型及群预测方法研究 总被引:1,自引:0,他引:1
库存管理是商业企业经营管理的重要组成部分,其管理应以销售出库量为主要依据,而客户需求的不确定性一直是困扰管理者的首要难题.提出在灰色GM(1,1)模型的基础上,结合残差时刻的灰灾变预测,建立了REM-GM(1,1)模型,并采用群预测的方法,对商业企业中的销售出库量进行了预测.经实证结果检验,表明该模型对商业企业的销售出库量的预测不论是单步预测还是多步远期预测,其预测精度与传统GM模型相比均有较大提高,且误差的波动较为稳定,其预测的结果是令人满意的. 相似文献
6.
在能量色散X荧光分析技术中,常用基本参数法、 经验系数法、 人工神经网络等方法建立计数率和元素含量之间的物理模型,此外,GMDH(group method of data handing)作为一种新型的处理复杂非线性问题的方法,被大量理论和实验证明优于大部分的计算统计方法。GMDH是一种自组织学习的前馈型网络,自动筛选并在训练过程中确定其结构,对GMDH进行改进并对结果进行定量预测,参考值与预测值的相对误差在5%以内,方法简洁、 合理、 可靠。 相似文献
7.
基于等维递补的多变量灰色组合预测模型 总被引:1,自引:1,他引:0
权双燕 《纯粹数学与应用数学》2009,25(1):203-208
利用等维递补建立单个多变量灰色预测模型,进而建立多变量灰色组合预测模型.通过实例说明多变量灰色组合模型的应用和效果. 相似文献
8.
近些年来,我国的国民经济一直是以每年10%以上的速度增长,由此可以预测:随着我国经济欣欣向荣的高速发展,到21世纪将有许多大型工程逐步上马、走向世界大工程的行列。为此,我国的工程地质工作者应先行研究:大型工程前期的工程地质可行性论证。工程开拓期间可能遇到的工程地质难题和新题;工程竣工后的环境工程地质预测及防治等问题,为未来的大型工程设计与施工提供可靠的工程地质依据。 相似文献
9.
在小子样结构响应试验数据样本的基础上,利用支持向量机回归的方法模拟了圆柱壳体动态极限应变峰值同壳体几何尺寸和外加脉冲载荷大小的非线性函数关系,同时通过改进的模拟退火单纯形混合算法优化了支持向量机的性能参数,并将支持向量机回归分析的预测性能同BP人工神经网络方法做了比较,验证了具有优化性能参数组合的支持向量机在小样本条件下更好的预测和推广能力. 最后,从支持向量机回归模型导出了大尺寸圆柱壳体抗脉冲载荷的强度极限同自身几何尺寸的多元函数关系,从而为该类型壳体设备抗脉冲载荷的强度分析提供了一个可借鉴的预估模型. 研究结果表明了支持向量机在机械结构的强度预估和可靠性分析等力学领域具有广泛的应用前景. 相似文献
10.
Jiying Huang Shengli Lin Xuewen Ma 《International Journal of Infrared and Millimeter Waves》2000,21(10):1603-1606
While the millimeter radio wave propagates through rainfall, it will be attenuated heavily due to assimilation and scattering of rain. It is imperative to establish a simple and effective model to predict the rain-induced attenuation. In this paper, the rainfall is taken as a random system that can attenuate the radio wave. The transfer function matrix model is selected to be the random system model. Using experiment rain attenuation data at different rain rate, the correlation entropy and residue error of the system is obtained by system identification method. On the basis of correlation entropy and residue error, we can determine the order of the predication system. At last, the predication model that can forecast heavy rain attenuation by small rain attenuation is gotten by applying the least square method. The comparison shows that the discrepancy between the predication result of the obtained model and the experiment rain attenuation data is relatively minor. 相似文献