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马铃薯块茎生成期的无损伤测定:—积温测定法
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作者 Jef.,R.A 许锦宇 《甘肃科技情报》 1989年第2期36-39,共4页
关键词 块茎生成期 无损伤测定 马铃薯
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兽医临床上几种无损伤骨矿测定方法简介 被引量:4
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作者 张皎 侯加法 《畜牧与兽医》 北大核心 2002年第3期38-40,共3页
无损伤骨矿测定法是活体测定动物或人的骨密度和骨矿含量的一种先进技术。它具有辐射量低或无辐射、精确度高、准确性好的特点 ,已广泛应用于医学临床 ,有的已用于兽医临床。本文简要介绍几种无损伤骨矿测定技术及其在兽医临床上的应用 ... 无损伤骨矿测定法是活体测定动物或人的骨密度和骨矿含量的一种先进技术。它具有辐射量低或无辐射、精确度高、准确性好的特点 ,已广泛应用于医学临床 ,有的已用于兽医临床。本文简要介绍几种无损伤骨矿测定技术及其在兽医临床上的应用 ,比较其优劣 ,为畜禽骨骼营养代谢、生理。 展开更多
关键词 无损伤骨矿测定 兽医临床应用 骨密度 骨矿含量 X线平片法 单光子吸收法
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基于水活度测定草类植物种子含水量 被引量:2
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作者 陈利军 王靖靖 +1 位作者 陈香来 胡小文 《草业科学》 CAS CSCD 2018年第9期2148-2156,共9页
种子含水量是衡量种子质量的重要指标,快速准确地测定种子含水量对于种子的安全贮藏与质量评价具有重要意义,本研究分析了箭筈豌豆(Vicia sativa)等8种常见草类植物种子水活度与种子含水量的关系。首先探讨了测量温度、样品量、平衡时... 种子含水量是衡量种子质量的重要指标,快速准确地测定种子含水量对于种子的安全贮藏与质量评价具有重要意义,本研究分析了箭筈豌豆(Vicia sativa)等8种常见草类植物种子水活度与种子含水量的关系。首先探讨了测量温度、样品量、平衡时间对种子样品水活度测定的影响,进而构建了适宜条件下水活度与种子含水量之间的数学预测模型,并对模型进行了验证与修正。结果表明,水活度测定易受平衡温度、平衡时间与样品量的影响,随平衡温度升高,同一样品水活度值减少;样品量越大,平衡时间越短,当种子占测量室2/3,平衡时间只需2~6min。20℃条件下,8种草类植物种子含水量和水活度均呈S-函数。基于8种草类植物种批种子含水量预测模型验证表明,基于水活度测定的种子含水量(相比低恒温测定法)相对偏差较低,平均小于2%,可用于种子含水量的无损快速测定。 展开更多
关键词 温度 S-函数 模型 安全贮藏 无损伤测定 低恒温测定 平衡时间
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Experimental study of structural damage identification based on WPT and coupling NN 被引量:1
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作者 郭健 陈勇 孙炳楠 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期663-669,共7页
Too many sensors and data information in structural health monitoring system raise the problem of how to realize multi-sensor information fusion. An experiment on a three-story frame structure was conducted to obtain ... Too many sensors and data information in structural health monitoring system raise the problem of how to realize multi-sensor information fusion. An experiment on a three-story frame structure was conducted to obtain vibration test data in 36damage cases. A coupling neural network (NN) based on multi-sensor information fusion is proposed to achieve identification of damage occurrence, damage localization and damage quantification, respectively. First, wavelet packet transform (WPT) is used to extract features of vibration test data from structure with different damage extent. Then, data fusion is conducted by assembling feature vectors of different type sensors. Finally, three sets of coupling NN are constructed to implement decision fusion and damage identification. The results of experimental study proved the validity and feasibility of the proposed methodology. 展开更多
关键词 Damage identification Experimental study Wavelet packet transform (WPT) Coupling neural network (NN)
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Noninvasive photoacoustic measurement of absorption coefficient using internal light irradiation of cylindrical diffusing fiber
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作者 彭东青 朱莉莉 +1 位作者 李志芳 李晖 《Optoelectronics Letters》 EI 2017年第5期367-371,共5页
Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and in... Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and internal light irradiation of cylindrical diffusing fiber(CDF) to quantify the target optical absorption coefficient. Absorption coefficients for ink absorbers are firstly determined through photoacoustic and spectrophotometric measurements at the same excitation, which demonstrates the feasibility of this method. Also, the optical absorption coefficients of ink absorbers with several concentrations are measured. Finally, the two-dimensional scanning photoacoustic image is obtained. Optical absorption coefficient measurement and simultaneous photoacoustic imaging of absorber non-invasively are the typical characteristics of the method. This method can play a significant role for non-invasive determination of blood oxygen saturation, the absorption-based imaging and therapy. 展开更多
关键词 Imaging techniques IRRADIATION Light absorption Photoacoustic effect
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