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排序方式: 共有185条查询结果,搜索用时 15 毫秒
1.
一种新颖的双边缘滤波光纤布拉格光栅解调技术 总被引:5,自引:5,他引:0
设计了一种基于机械感生长周期光纤光栅(MI-LPG)的双边缘滤波光纤布拉格光栅(FBG)传感解调方案。采用不同写制参数制作了谐振边带对称交迭,谐振峰值和带宽相同的两个MI-LPG作为滤波器,利用反射FBG信号通过不同光谱特性的滤波器时输出不同光强的比值对数算法确定被测波长。实验表明,本解调方法能够精确、稳定地实现FBG传感信号的解调,动态范围可达5 nm,解调系统线性拟合计算值和光谱仪所测波长值的均方差为6 pm,线性度好,精度高。 相似文献
2.
The objective of the presented study was to test various oxidation processes with the aim being to reduce the concentration and toxicity of biocide wastewater from a Slovenian phytopharmaceutical factory. Laboratory-scale experiments employing two AOP processes – ozonation (O3) and peroxone (H2O2/O3) – were applied to reduce the concentration of the active components involved, i.e., methylisothiazolone (MI), chloromethylisothiazolone (CMI) and dichloromethylisothiazolone (DCMI). The reduction of the biocide wastewater load for the performed oxidation processes was evaluated using ecological parameters. The H2O2/O3 oxidation procedure using an O3 flow rate of 1g/L h, at a pH value of 10 and with the addition of 5 ml of H2O2 (0.3 M) proved to be the most effective treatment. The toxicity of the biocide-load wastewater with an initial EC50 = 0.38%, decreased to EC50 (24h) >100% and EC50 (48h) = 76%. 相似文献
3.
针对传统互信息图像配准拼接算法计算量大、效率低等问题,本文结合模板匹配,提出基于模板与互信息的全景图拼接技术。首先将误差法和二次匹配误差法相结合,对待拼接图像进行初次模板匹配,划定大致重叠区域;接着从互信息量的角度比较相邻重叠的两幅图像的相似性,通过建立两幅图像之间的互信息量,计算最大互信息,获得匹配区域;然后再次利用模板匹配,设定最佳匹配区域,最终实现图像配准拼接。在VS2010+Opencv环境中编程实现重叠图像的拼接,并验证了算法的正确性。实验表明,本文算法具有计算量相对小,自动化程度高,配准拼接精度高等优点。 相似文献
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Srinivas Ravindra Babu Behara Paul Kippax Ian Larson David A.V. Morton Peter Stewart 《Chemical engineering science》2011,(21):72
The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min−1) from three dry powder inhaler devices, Rotahaler® (RH), Monodose Inhaler® (MI) and Handihaler® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (kCCEM), estimated from a modelling approach, increased with increasing air flow rates. The kCCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The kCCEM was highest from RH and lowest from MI. Differences in kCCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers. 相似文献
6.
为进一步提高锅炉系统水冷壁温度的预测精度,提出一种基于变量优化和改进鲸鱼算法优化长短期记忆神经网络的水冷壁温度预测模型。首先,通过互信息算法(MI)进行变量选择,消除初始数据中的冗余变量;其次,使用经验模态分解算法(EMD)对变量选择后的数据进行特征分解,在提取变量有效特征信息的同时降低噪音干扰;最后,使用由非线性递减因子和自适应权值改进后的鲸鱼优化算法(Improved Whale Optimization Algorithm,IWOA)确定长短期记忆神经网络(LSTM)的超参数,得到一种新型锅炉系统水冷壁温度预测模型(MI EMD IWOA LSTM)。实验结果表明,相比传统的最小二乘支持向量机(LSSVM)预测模型,MI EMD IWOA LSTM模型的均方根误差(RMSE=0.306 8)和平均绝对百分比误差(MAPE=0.054 6)最低,能够实现对锅炉系统水冷壁工质温度的精准预测。 相似文献
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在意大利FARE公司卧式一步法丙纶高强丝设备上,研究了聚丙烯熔融指数与丙纶高强丝强度的关系。探讨了纺丝温度、冷却条件、单丝纤度、拉伸倍数等主要工艺条件对丙纶高强丝强度的影响。 相似文献
9.
Robust Transmission Waveform Design for Distributed Multiple‐Radar Systems Based on Low Probability of Intercept 下载免费PDF全文
This paper addresses the problem of robust waveform design for distributed multiple‐radar systems (DMRSs) based on low probability of intercept (LPI), where signal‐to‐interference‐plus‐noise ratio (SINR) and mutual information (MI) are utilized as the metrics for target detection and information extraction, respectively. Recognizing that a precise characterization of a target spectrum is impossible to capture in practice, we consider that a target spectrum lies in an uncertainty class bounded by known upper and lower bounds. Based on this model, robust waveform design approaches for the DMRS are developed based on LPI‐SINR and LPI‐MI criteria, where the total transmitting energy is minimized for a given system performance. Numerical results show the effectiveness of the proposed approaches. 相似文献
10.