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基于遗传规划的炸弹弹道分组拟合模型
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作者 冯琦 孙宁 +1 位作者 朱金冬 高晓光 《系统工程与电子技术》 EI CSCD 北大核心 2019年第4期787-792,共6页
针对传统弹道拟合方法需要事先设定拟合方程的函数结构形式且不能很好适应大范围投射条件的问题,提出了一种分组遗传规划的炸弹弹道拟合方法。首先,依据动力学仿真实验得到炸弹在不同投射条件下的弹道样本。然后,采用分组遗传规划对样... 针对传统弹道拟合方法需要事先设定拟合方程的函数结构形式且不能很好适应大范围投射条件的问题,提出了一种分组遗传规划的炸弹弹道拟合方法。首先,依据动力学仿真实验得到炸弹在不同投射条件下的弹道样本。然后,采用分组遗传规划对样本数据中弹道诸元和投射初值进行输入-输出映射拟合训练,得到了多组弹道拟合方程,并进行了未分组和分组拟合方程式之间的精度和泛化性比较。大量检测验算说明,采用分组遗传规划得到的弹道拟合方程式组具有物理关系明确、拟合精度高、泛化好、实时解算快等特性。 展开更多
关键词 激光制导炸弹 弹道诸元 分组遗传规划 拟合方程式
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电涡流传感器特性曲线拟合的新方法 被引量:9
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作者 薛亚琴 刘奕平 《传感器技术》 CSCD 北大核心 2003年第7期42-44,共3页
为了减小电涡流传感器的非线性误差,在最小二乘法的基础上,结合0.618优选法,使拟合方程式中的常数更合理。用这种方法可以求得最佳拟合直线方程和最小的非线性误差。此法适用于各种类型的线性传感器或可以通过适当的变量代换把变量之间... 为了减小电涡流传感器的非线性误差,在最小二乘法的基础上,结合0.618优选法,使拟合方程式中的常数更合理。用这种方法可以求得最佳拟合直线方程和最小的非线性误差。此法适用于各种类型的线性传感器或可以通过适当的变量代换把变量之间的非线性关系化为线性关系的传感器或测量系统。 展开更多
关键词 电涡流传感器 特性曲线 非线性误差 拟合方程式
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基于最小二乘拟合的墙面平整度检测方法 被引量:20
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作者 程效军 唐剑波 《测绘信息与工程》 2007年第4期19-20,共2页
介绍了通过测定墙面上多个点对其平整度进行检测的方法,阐述了基于最小二乘拟合的墙面平整度检测方法,实现了对墙面施工精度的评定。
关键词 测定墙面多点坐标 最小二乘法 墙面方程式
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SARS患者血浆纤维结合蛋白水平变化及其意义
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作者 欧阳锡林 刘景汉 +7 位作者 郭廷凯 于洋 王海宝 马曙轩 姚伟 田亚平 许红民 张婷 《华南国防医学杂志》 CAS 2003年第6期4-5,共2页
目的:探索急性期SARS患者和康复期SARS患者血浆纤维结合蛋白(plasma Fibronectin,Fn)的水平变化及输注血浆Fn纠正治疗急性期SARS患者的可行性。方法:急性期SARS组为4名住院的急性期SARS患者;康复期SARS组为111名康复期SARS住院患者;对... 目的:探索急性期SARS患者和康复期SARS患者血浆纤维结合蛋白(plasma Fibronectin,Fn)的水平变化及输注血浆Fn纠正治疗急性期SARS患者的可行性。方法:急性期SARS组为4名住院的急性期SARS患者;康复期SARS组为111名康复期SARS住院患者;对照组为随机26名体检合格的无偿献血者。采用ELISA法测定各族组血浆Fn水平。结果:急性期SARS组血将Fn浓度为(42.2±23.0)mg/L;恢复期SARS组血浆Fn浓度为(379.45±93.27)mg/L;对照组血浆Fn浓度为(359.21±52.54)mg/L。急性期SARS组血浆Fn浓度显著低于对照组(P=0.001);急性期SARS组与恢复期SARS组血浆Fn浓度差异极显著(P=0.000);恢复期SARS与对照组血浆Fn浓度无显著差异(P=0.289)。结论:急性期SARS患者血浆纤维结合蛋白水平显著降低,为输注外源性的纤维结合蛋白治疗SARS提供了依据。SARS患者血浆Fn水平的变化可能是辅助诊断和判断SARS病情的指标之一。 展开更多
关键词 SARS 血浆纤维结蛋白 输血治疗拟合方程式
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农村电力系统负荷预测的研究——基于Excel回归模型 被引量:5
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作者 赵玉林 高英 《农机化研究》 北大核心 2014年第2期226-228,244,共4页
农村电力系统负荷预测是农村电网供电规划的基础。当利用回归模型进行农村电力系统负荷预测时,最大的问题是:当给定的历史数据量很大、回归模型未知数的最高次项的次数较高时,求解回归方程计算将变复杂。针对上述问题,提出了一种基于Ex... 农村电力系统负荷预测是农村电网供电规划的基础。当利用回归模型进行农村电力系统负荷预测时,最大的问题是:当给定的历史数据量很大、回归模型未知数的最高次项的次数较高时,求解回归方程计算将变复杂。针对上述问题,提出了一种基于Excel的回归模型的求解方法,该方法无需编程,操作简单。计算结果表明,基于Excel的回归模型进行农村电力负荷预测的方法简单实用,误差较小。 展开更多
关键词 农村电力系统 负荷预测 回归模型 方程式 最小二乘法
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Measuring Carbon Dioxide Sink of Betung Bamboo (Dendrocallamus asper (Schult f.) Backer ex Heyne) by Sinusoidal Curves Fitting on Its Daily Photosynthesis Light Response 被引量:1
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作者 Effendi Tri Bahtiar Naresworo Nugroho Anne Carolina Aditya Chandra Maulana 《Journal of Agricultural Science and Technology(B)》 2012年第7期780-788,共9页
Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditiona... Planting plant such as Betung bamboo (Dendrocalamus asper (Schult f.) Backer ex Heyne) is one of the best ways for reducing global warming effect. Betung bamboo is giant grass (Poaceae) which has been traditionally used by Indonesian people for construction material since a long time ago. Poaceae family commonly has better carbon sink ability than trees because of its Ca photosynthesis mechanisms, but bamboo sub-family (Bambusoideae) lacks the Ca photosynthetic pathway and anatomy. In the absence of this feature the maximum possible productivity of bamboos is unlikely to greatly exceed that of other bioenergy crops with C3 photosynthesis such as fast growing tree species. This research proposed a sinusoidal equation as a basic equation for plant's daily photosynthesis light response curve fitting. The sinusoidal equation was success for Betung bamboo's daily photosynthesis light response curve fitting (R2 〉 60%). It had similar result in estimating carbon sink (82.35 kg/clump/year) compared to those which calculated by annual increment (69.01-107.82 kg/clump/year). It is better to choose sinusoidal equation than quadratic or cubic Betung bamboo is a good choice to be planted in order to resist the global warming effect because it has superior carbon sink capability (82.35 kg/clump/year) than slow growing tree, and equal to fast growing tree species, besides many other advantages. 展开更多
关键词 Carbon sink Betung bamboo daily photosynthesis light response sinusoidal curve fitting.
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Evaluating instrumented Charpy impact strain signals using curve fitting equations 被引量:1
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作者 M.B.Ali S.Abdullah +2 位作者 M.Z.Nuawi A.K.Ariffin Z.M.Nopiah 《Journal of Central South University》 SCIE EI CAS 2014年第2期600-609,共10页
An effective and simple way to develop equations from impact strain signals was proposed.Little research has been performed in this area,but this equation is very important for evaluating input signals in finite eleme... An effective and simple way to develop equations from impact strain signals was proposed.Little research has been performed in this area,but this equation is very important for evaluating input signals in finite element analysis impact tests and for obtaining additional information on material deformation and fracture processes under impact loading.For this purpose,dynamic impact responses were examined through signals obtained from a strain gauge installed on an impact striker connected to a data acquisition system.Aluminium 6061-T6 was used to extract strain responses on the striker during Charpy impact testing.Statistical analysis was performed using the I-kaz method,and curve fitting equations based on the equation for vibration response under a non-periodic force were used to evaluate the Charpy impact signals.The I-kaz coefficients and curve fitting equations were then compared and discussed with related parameters,such as velocities and thicknesses.Velocity and thickness were found to be related to the strain signal patterns,curve fitting equations and I-kaz coefficients.The equations developed using this method had R2 values greater than 97.7%.Finally,the constructed equations were determined to be suitable for evaluating Charpy impact strain signal patterns and obtaining additional information on fracture processes under impact loading. 展开更多
关键词 charpy impact curve fitting I-kaz signal and strain
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Polynomial Quasisolutions Method for Some Linear Differential Difference Equations of Mixed Type
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作者 Valery Cherepennikov Natalia Gorbatskaia Polina Sorokina 《Journal of Mathematics and System Science》 2014年第4期225-230,共6页
The paper considers a scalar linear differential difference equation (LDDE) of mixed type x(t) = (a0 + a1t)X(t) + (b0 + b1t)x(t - 1) + (d0 + d1tx(t + 1) + f(t), t ∈ R, (*) where f(t) = ∑... The paper considers a scalar linear differential difference equation (LDDE) of mixed type x(t) = (a0 + a1t)X(t) + (b0 + b1t)x(t - 1) + (d0 + d1tx(t + 1) + f(t), t ∈ R, (*) where f(t) = ∑n=0^F fn^tn. This equation is investigated with the use of the method of polynomial quasisolutions based on the representation of an unknown function in the form of polynomial x(t) = ∑n=0^N xn^tn. As a result of substitution of this function into equation (*), there appears a residual △(t) = 0(t^N), for which an exact analytical representation has been obtained. In turn, this allows one to find the unknown coefficients xn and consequently the polynomial quasisolution x(t). Several examples are considered. 展开更多
关键词 Diffrential difference equations initial value problem polynomial quasisolutions
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工作面残余瓦斯参数快速测定方法及装置
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作者 于宝海 王建伟 许占营 《煤矿安全》 CAS 北大核心 2013年第12期17-19,共3页
针对残余瓦斯参数测定存在周期长、可靠性差问题,提出了一种新型快速测定方法。该方法通过井下测定装置连续测得煤样粉碎前后的瓦斯解吸量,并结合实验室预先拟合的煤吸附甲烷不同平衡压力与解吸量及甲烷含量曲线方程,准确计算出测点的... 针对残余瓦斯参数测定存在周期长、可靠性差问题,提出了一种新型快速测定方法。该方法通过井下测定装置连续测得煤样粉碎前后的瓦斯解吸量,并结合实验室预先拟合的煤吸附甲烷不同平衡压力与解吸量及甲烷含量曲线方程,准确计算出测点的残余瓦斯含量和压力。 展开更多
关键词 残余瓦斯 快速测定 等温解吸 拟合方程式 瓦斯解吸量
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