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Convergence ball and error analysis of Ostrowski-Traub’s method

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Applied Mathematics(A Journal of Chinese Universities) 2010年第3期25卷 374-378页

作者： bi wei-hong WU Qing-biao REN hong-min Department of Mathematics Zhejiang University Hangzhou 310027 China Department of Information and Electronics Hangzhou Radio and TV University Hangzhou 310012 China

Under the hypotheses that the second-order and third-order derivatives of a function are bounded, an estimate of the radius of the convergence ball of Ostrowski-Traub＇s method is obtained. An error analysis is given which matches the convergence order of the method. Finally, two examples are provided to show applications of our theorem.

关键词： Ostrowski-Traub's method nonlinear equation convergence ball estimate of radius error analysis

Analysis of photonic crystal fiber sensor character

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Optoelectronics Letters 2007年第3期3卷 199-202页

作者： GUO Xuan LIU Feng bi wei-hong College of lnformation Science and Engineering Yanshan University Qinhuangdao 066004 China

The special character of a PCF which is used as a gas or liquid sensor is discussed. The field distribution is analyzed when the solid core PCF is injected with different medium that has different relative dielectric constant （or refractive index）. And the experiential formulas of the relation between refractive index of some kinds of liquid and their concentration are given, in order to measure the concentration of the relative liquid. At the same time, the effect of propagation constant on PCF sensor character is also discussed. Furthermore, the photonic medium relative dielectric constant, when it is injected with . band-gap （PBG） of PCF （PBG-PCF） is calculated at different different medium. That is the principle basis for this kind of PCF sensors.

关键词：光子晶体光纤传感器性能分析介电常数

Determination of ethanol content in ethanol-gasoline based on derivative absorption spectrometry and information fusion

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Optoelectronics Letters 2018年第6期14卷 442-446页

作者： ZHOU Kun-peng BAI Xu-fang bi wei-hong School of Physics and Electronic Information Inner Mongolia University for Nationalities The Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science and Engineering Yanshan University

The ethanol content in ethanol-gasoline is respectively detected by the first-order derivative UV/vis absorption spectrum, the first-order derivative near infrared(NIR) absorption spectrum and the information fusion method. The backward interval partial least squares(biPLS) algorithm is used as the feature extraction method, which is established by the partial least squares(PLS) regression model. Based on the information fusion theory, the low level data fusion(LLDF) and mid-level data fusion(MLDF) models are established by the first-order derivative UV/vis and NIR spectra. The analytical results are compared with the related textual references. Thereby, the single-spectral model based on the first-order derivative NIR absorption spectrum has the optimal results, where R_p^2 =0.999 1 and RMSEP=0.324 5, while the LLDF after vector normalization(LLDF-VN2) is the optimal multi-spectral fusion model, where R_p^2 =0.998 3 and RMSEP=0.498 2. The proposed method can be used to detect the ethanol content in ethanol-gasoline rapidly and provides a better choice for the component detection in mixed oils.

关键词： derivative absorption spectrometry information fusion ethanol-gasoline

A double-cladding fiber curvature sensor based on the extrinsic Fabry-Perot interferometer

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Optoelectronics Letters 2019年第1期15卷 6-10页

作者： FU Xing-hu WANG Dong LIU Lian-xu LIU Fan WEN Jing FU Guang-wei bi wei-hong The Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science and Engineering Yanshan University

Based on the principle of Fabry-Perot (F-P) interference, a new type of optical fiber curvature sensor is presented,which is fabricated by single-mode fiber(SMF), ceramic tube and double-cladding fiber (DCF). And the curvature sensing properties are analyzed, and the double-peak method is used to demodulate the cavity length. The experimental results show that the F-P interference spectrum shifts toward long wavelengths with increasing the curvature. And the sensors are placed in different positions on the cantilever to get their different curvature sensitivities. Smaller initial cavity length gives greater sensor sensitivity. The best curvature sensitivity is achieved as 2 554.53 pm/m^(-1) in 0.71—1.18 m^(-1). By demodulating the length of the F-P cavity, the cavity length of sensor 4 is changed by 0.08 mm. Therefore, the sensor has some potential for measure the small displacement.

关键词： double-cladding fiber Fabry-Perot

基于近红外光谱法的多组分复杂溢油源定量建模分析

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光谱学与光谱分析 2012年第12期32卷 3203-3207页

作者：谈爱玲毕卫红燕山大学信息科学与工程学院河北省特种光纤与光纤传感重点实验室河北秦皇岛066004

研究利用近红外光谱分析方法进行模拟复杂混合溢油源的定量分析问题。选取汽油、柴油、煤油三种轻质石油类产品,按照不同浓度比例配置成40个模拟混合溢油样本,利用傅里叶变换近红外光谱仪采集其在4 000～12 000cm-1谱区范围内的近红外光... 详细信息

研究利用近红外光谱分析方法进行模拟复杂混合溢油源的定量分析问题。选取汽油、柴油、煤油三种轻质石油类产品,按照不同浓度比例配置成40个模拟混合溢油样本,利用傅里叶变换近红外光谱仪采集其在4 000～12 000cm-1谱区范围内的近红外光谱;采用不同预处理方法,利用偏最小二乘算法建立混合溢油样本三组分各自的浓度定量模型。汽油、柴油和煤油的最优预处理方法均为二阶导数方法,分别在8 501.3～7 999.8cm-1,6 102.1～4 597.8cm-1,6 549.5～4 597.8cm-1,7 999.8～7 498.4cm-1和6 102.1～4 597.8cm-1谱区范围内,预测模型的决定系数R2分别为0.998 2,0.990 2和0.993 6;RMSEP值分别为0.474 7,0.936 1和1.013 1;RPD值分别为25.126 9,10.517 3和13.072 0。实验结果表明:利用近红外光谱分析技术结合化学计量学方法能够定量确定模拟混合溢油样本中各组分的浓度,为海洋复杂溢油源的定量检测与分析提供有效手段。

关键词：近红外光谱复杂溢油源定量建模偏最小二乘

A robust salinity sensor based on encapsulated long-period grating in microfiber

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Optoelectronics Letters 2020年第6期16卷 418-422页

作者： WU Shu-hui JIN Wa bi wei-hong LI Xia ZHANG Lin-ke JIN Yun Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science and EngineeringYanshan UniversityQinhuangdao 066004China Department of Mechanical and Electrical Engineering Hebei Construction Material Vocational and Technical CollegeQinhuangdao 066004China

A robust fiber sensor for salinity measurement based on encapsulated long-period grating in microfiber is proposed. The long-period grating is fabricated in microfiber by inducing periodical deformation with CO2 laser, which is then encapsulated in a holey capillary tube. The encapsulation tube is designed to effectively protect the microfiber from external interference, but does not change the optical properties of the fiber and the response speed of the sensor, which makes the sensor more robust for real applications. Experimental results show that the sensor can achieve a sensitivity of 2.16 nm/% with a good linearity for concentration from 0% to 20%. It is theoretically proved that the sensitivity can be further improved by optimizing the diameter parameters. Such structure may be used as low loss evanescent-wave-coupled optical absorption, fluorescent and gain cells, photoacoustic cells, and etc.

关键词： LPG A robust salinity sensor based on encapsulated long-period grating in microfiber

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保偏微结构光纤啁啾光栅折射率传感特性分析

光谱学与光谱分析 2013年第1期33卷 266-270页

作者：郭璇毕卫红刘丰燕山大学信息科学与工程学院河北秦皇岛066004

将有限元法和传输矩阵法相结合,系统地研究了保偏微结构光纤(PM-MOF)啁啾布拉格光栅的折射率传感特性。仿真研究了光纤空气孔中充入不同折射率被测物时啁啾光栅的反射谱,结果表明随着被测物折射率的增加,反射谱的面积出现明显变化,由此... 详细信息

将有限元法和传输矩阵法相结合,系统地研究了保偏微结构光纤(PM-MOF)啁啾布拉格光栅的折射率传感特性。仿真研究了光纤空气孔中充入不同折射率被测物时啁啾光栅的反射谱,结果表明随着被测物折射率的增加,反射谱的面积出现明显变化,由此得到了光栅反射谱面积与被测物折射率的关系。分析了中心孔直径、啁啾系数、切趾函数等光栅结构参数对反射谱的影响。分析表明由于光纤两个方向的偏振模对温度、噪声等干扰响应相似,因此利用两个偏振模式反射谱的相对变化进行监测能够有效地降低干扰,提高传感器的稳定性;其次,由于反射谱面积正比于光强,这一方法将光栅的光谱解调转化为光强解调,简化了解调系统,便于现场实时测量。研究结果为保偏微结构光纤光栅在折射率传感器及其生物传感器方面的应用提供了理论依据。

关键词：保偏微结构光纤啁啾布拉格光栅传输矩阵法折射率传感

基于稀疏非负矩阵分解和支持向量机的海洋溢油近红外光谱鉴别分析

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光谱学与光谱分析 2011年第5期31卷 1250-1253页

作者：谈爱玲毕卫红赵勇燕山大学信息科学与工程学院光电子工程系河北秦皇岛066004 燕山大学电气工程学院生物医学工程系河北秦皇岛066004

提出一种海洋溢油近红外光谱特征提取与种类鉴别新方法。海面溢油种类鉴别对现场应急处置方案的制定和可疑溢油源的追踪具有重要意义。采用傅里叶变换近红外光谱仪测定汽油、柴油、煤油三类模拟海洋溢油样本的近红外光谱,基于稀疏非负... 详细信息

提出一种海洋溢油近红外光谱特征提取与种类鉴别新方法。海面溢油种类鉴别对现场应急处置方案的制定和可疑溢油源的追踪具有重要意义。采用傅里叶变换近红外光谱仪测定汽油、柴油、煤油三类模拟海洋溢油样本的近红外光谱,基于稀疏非负矩阵分解算法对光谱进行特征提取,采用五重交叉检验,对210个样本进行训练,建立基于支持向量机的溢油光谱定性分析模型,同时讨论非负特征基数目以及稀疏因子对分类正确率的影响;利用训练好的分类器对90个未知样本进行鉴别,识别正确率达97.78%。所提出的稀疏非负矩阵分解结合支持向量机的近红外光谱定性分析方法,识别正确率高,模型泛化能力强,具有很好的分类效果,为海洋溢油的快速鉴别提供了新途径。

关键词：近红外光谱海洋溢油稀疏非负矩阵分解支持向量机

Mach-Zehnder电光调制器产生多波长光源的实验研究

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光电工程 2011年第7期38卷 7-12页

作者：毕卫红刘银燕山大学信息科学与工程学院河北秦皇岛066004

随着对光纤通信容量需求的不断增长,DWDM系统和L波段光器件成为当今研究的热点,多波长光源作为重要的有源器件倍受青睐。本文研究了基于Mach-Zehnder结构的电光强度调制器的理论模型,利用公式仿真得到在一定微波功率调制下强度调制器输... 详细信息

随着对光纤通信容量需求的不断增长,DWDM系统和L波段光器件成为当今研究的热点,多波长光源作为重要的有源器件倍受青睐。本文研究了基于Mach-Zehnder结构的电光强度调制器的理论模型,利用公式仿真得到在一定微波功率调制下强度调制器输出的扩频光谱。实验研究了M-Z结构的集成电光波导强度调制器光波长1550nm处10GHz、15GHz、20GHz扩频的实现,对理论分析所得的输出光谱与实际系统的输出光谱进行比较,发现谱线情况较一致。在调制频率10GHz,调制深度C=1.39,V=2.98V时,输出光谱中可清楚观察到正负三阶等频率间隔的边波带,尤其是一阶边波带与中心波长峰值功率几乎相等,可实现三路光源等功率输出。

关键词：密集波分复用技术多波长光源光谱扩频电光强度调制器