检索结果-南通市图书馆

Quantitative and qualitative measurement of pear firmness based on near infrared spectroscopy and chemometrics

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2008年第1期1卷 69-74页

作者： fu xiaping Ying Yibin Zhou Ying Lu Huishan Xu Huirong College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310029China

Firmness is one of the most important characteristics to estimate fruit maturity and *** potential of near-infrared(NIR)diffuse reflectance spectroscopy as a nondestructive way for pear firmness evaluation of three varieties(‘Cuiguan’,‘Xueqing’and‘Xizilv’)was studied,both quantitatively and *** models were established using partial least square(PLS)methods in the spectral range of 800 to 2500 *** quantitative analysis,the correlation coefficient r increased with more varieties involved in the *** results were obtained in the model for all three varieties:rcalwas 0.934,root mean square error of calibration(RMSEC)and root mean square error of prediction(RMSEP)were 2.06 N and 3.14 N,*** qualitative analysis,the overall accuracies of discriminant PLS models for classifying pears into three firmness levels:low,medium and high firmness level were not so good,percentage of samples correctly classified ranged from 70.63%to 81.25%for calibration and from 56.25%to 74.38%for *** results indicate that NIR spectroscopy together with PLS chemometrics method is feasible for quantitative analysis of pear firmness,however,the classification accuracy is too low to put into practical application.

关键词： Firmness pear near infrared partial least square quantitative measurement qualitative measurement

Design and feasibility analysis of a graded harvesting end-effector with the function of soluble solid content estimation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2024年第5期17卷 239-246页

作者： Yufei Lin Hao Liang Junhua Tong Haoyu Shen xiaping fu Chuanyu Wu College of Mechanical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Agriculture and Biotechnology Wenzhou Vocational College of Science and TechnologyWenzhou 325006ZhejiangChina College of Mathematics and Computer Science Zhejiang A&F UniversityHangzhou 311300China Zhejiang Ocean University Zhoushan 316002ZhejiangChina

In response to the prevailing scarcity of labor and with the aim of augmenting the proportion of premium-quality fruits, a robotic grading end-effector system for harvesting was meticulously designed. The end-effector could measure the soluble solid content (SSC) of peaches during the harvesting process to evaluate the quality of the fruit, thereby facilitating real-time grading during harvesting. As comprising a harvesting component and an information-gathering segment, the end-effector system was optimized with the primary structural parameters of its adaptive fingers using a mathematical model of peach morphology. Also, the buffering materials for mitigating the pressure exerted by the adaptive fingers on the peaches were compared. furthermore, feasibility analyses of the grasping actions were conducted based on the interaction forces between the adaptive fingers and the peaches. To grade the quality of peaches, SSC was used as an indicator to assess and grade the quality of the peaches. The spectra of peaches within the wavelength range of 590-1100 nm were collected, and a predictive model for SSC was developed. The correlation coefficients for the calibration set and prediction sets of the predictive model were 0.880 and 0.890, with corresponding root mean square errors of 0.370% and 0.357% Brix, respectively. In addition, a robustness and accuracy assessment was conducted using 30 peach samples, yielding a correlation coefficient of 0.936 and a standard error of 0.386% Brix between the predicted and measured values of SSC. The results confirm that the end-effector can measure the SSC of peaches during the collection process, providing novel concepts and theoretical foundations for real-time harvesting and grading.

关键词： robot harvesting graded end-effector soluble solids near-infrared spectroscopy

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

便携式荧光成像检测系统开发及应用研究

电子测量与仪器学报 2024年第9期38卷 169-175页

作者：张玮傅霞萍浙江理工大学信息科学与工程学院杭州310018

针对食品加工过程中设备表面食物残留快速检测的需求,以菠菜汁液为例开发了一套便携式荧光成像检测系统,并在此基础上增加系统对菠菜汁液中含量较高的物质叶绿素A的定量功能。该系统主要由光源、CCD相机、显示屏及控制处理单元组成,用... 详细信息

针对食品加工过程中设备表面食物残留快速检测的需求,以菠菜汁液为例开发了一套便携式荧光成像检测系统,并在此基础上增加系统对菠菜汁液中含量较高的物质叶绿素A的定量功能。该系统主要由光源、CCD相机、显示屏及控制处理单元组成,用于激发物质产生荧光的光源、滤波片可根据实际需求调整更换,同时开发了检测系统的控制软件,利用显示屏进行人机交互操作,主要实现图像数据采集和处理等功能。对3种广泛使用的食品加工材料表面的菠菜汁液残留开展定性实验,检测结果显示:当食品加工表面本身不具有荧光效应时,便携式荧光成像检测系统能够较好地识别出其上的叶绿素残留。对叶绿素A的定量检测结果表明,当叶绿素A溶液浓度在0~8.5μg/mL范围内时,浓度预测模型的决定系数R 2都能达到0.99,预测结果的均方根误差RMSE不高于0.24μg/mL。研究结果表明,开发的检测系统对具有特定荧光效应的物质检测可行且有效,系统具有的检测视场大、体积小便于携带等优点可将系统用于现场实时检测,也可拓展至植物病变等其他领域的应用,具有较广阔的应用前景。

关键词：荧光成像便携式实时检测浓度预测食物残留

Feasibility of Laser-Induced Breakdown Spectroscopy and Hyperspectral Imaging for Rapid Detection of Thiophanate-Methyl Residue on Mulberry Fruit

在线全文

学校读者我要写书评

暂无评论

Feasibility of Laser-Induced Breakdown Spectroscopy and Hype...

中国蚕学会第十届青年学术研讨会

作者： Di Wu Liuwei Meng Liang Yang Jingyu Wang xiaping fu Xiaoqiang Du Shaojia Li Yong He Lingxia Huang ZheJiang University

An effective and rapid way to detect thiophanate-methyl residue on mulberry fruit is important for providing consumers with quality and safe of mulberry *** methods are complex,time-consuming,and costly,and can result in sample *** detection of thiophanate-methyl residue on mulberry fruit was studied using laser-induced breakdown spectroscopy（LIBS） and hyperspectral imaging（HSI） *** component analysis（PCA） and partial least square regression（PLSR） were used to qualitatively and quantitatively analyze the data obtained by using LIBS and HSI on mulberry fruit samples with different thiophanate-methyl *** competitive adaptive reweighted sampling algorithm was used to select optimal *** results of model calibration were *** best result was given by the PLSR model that used the optimal preprocessed LIBS–HSI variables,with a correlation coefficient of 0.921 for the prediction *** results of this research confirmed the feasibility of using LIBS and HSI for the rapid detection of thiophanate-methyl residue on mulberry fruit.

关键词： mulberry laser-induced breakdown spectroscopy hyperspectral imaging pesticide residue chemometrics variable selection

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

手持式名优茶嫩梢采摘机械手设计与试验优化

农业机械学报 2022年第5期53卷 86-92页

作者：贾江鸣叶玉泽程培林朱赢鹏傅霞萍陈建能浙江理工大学机械与自动控制学院杭州310018 浙江省种植装备技术重点实验室杭州310018

针对名优茶机械化采摘难的问题,根据茶叶采摘农艺要求和手工采摘动作的分析,设计了一种手持式名优茶嫩梢采摘机械手,模拟人手指夹住茶叶并通过提拉进行采摘。通过采摘机械手的运动分析,得到了影响采摘效率的因素磁钢距离、主动手指角速... 详细信息

针对名优茶机械化采摘难的问题,根据茶叶采摘农艺要求和手工采摘动作的分析,设计了一种手持式名优茶嫩梢采摘机械手,模拟人手指夹住茶叶并通过提拉进行采摘。通过采摘机械手的运动分析,得到了影响采摘效率的因素磁钢距离、主动手指角速度和主动手指转角的参数变动范围。采用Box-Behnken响应面分析方法,研究影响因素对采摘成功率的交互影响,以采摘成功率为响应值建立二次回归模型,各因素对采摘成功率的影响显著性主次排序为:主动手指角速度、磁钢距离、主动手指转角;运用Design-Expert 11.0软件的优化模块,以采摘成功率为优化目标对各因素进行优化,得到优化参数为:磁钢距离40.04 mm、主动手指转角153.0°、主动手指角速度3.38 rad/s。以优化后的参数进行采摘试验,结果表明采摘成功率为74.3%,3次采摘平均速度为25.2个/min,试验值与预测值的相对误差小于5%,优化模型结果可靠。

关键词：名优茶采摘机械手响应面采摘成功率

维普期刊数据库博看期刊

在线全文

学校读者我要写书评

暂无评论

西瓜可溶性固形物含量近红外透射检测技术

农业机械学报 2007年第5期38卷 111-113页

作者：田海清应义斌徐惠荣陆辉山傅霞萍浙江大学生物系统工程与食品科学学院

设计的近红外透射式西瓜可溶性固形物含量(SSC)检测系统主要包括光纤光谱仪、光纤透射附件、数据采集卡以及自制光源。对50个麒麟瓜SSC进行了预测试验,采用主成分回归和偏最小二乘回归法分别建立了样品的原始光谱、一阶微分光谱、二阶... 详细信息

设计的近红外透射式西瓜可溶性固形物含量(SSC)检测系统主要包括光纤光谱仪、光纤透射附件、数据采集卡以及自制光源。对50个麒麟瓜SSC进行了预测试验,采用主成分回归和偏最小二乘回归法分别建立了样品的原始光谱、一阶微分光谱、二阶微分光谱和SSC的预测模型,结果表明偏最小二乘回归法建立的模型具有较高的相关性,相关系数为0.951,均方根校正误差0.347,均方根预测误差0.302,样本真实值与预测值的相关系数为0.910。

关键词：西瓜近红外透射可溶性固形物含量检测系统

肥胖儿童血清25-羟基维生素D和骨密度水平的变化及临床价值

在线全文

学校读者我要写书评

暂无评论

实用检验医师杂志 2021年第2期13卷 80-83页

作者：罗邱付小平湖南省儿童医院体检中心湖南长沙410007

目的探讨肥胖儿童与正常儿童25-羟基维生素D〔25(OH)D〕与骨密度的差异,分析肥胖与25(OH)D缺乏的关系。方法分析2019年12月—2020年8月湖南省儿童医院体检中心100名学龄期儿童的体检结果,以其中59名超重和肥胖儿童作为肥胖组,其余41名... 详细信息

目的探讨肥胖儿童与正常儿童25-羟基维生素D〔25(OH)D〕与骨密度的差异,分析肥胖与25(OH)D缺乏的关系。方法分析2019年12月—2020年8月湖南省儿童医院体检中心100名学龄期儿童的体检结果,以其中59名超重和肥胖儿童作为肥胖组,其余41名体质量正常儿童作为对照组。收集两组临床资料,采用酶联免疫吸附试验(ELISA)测定儿童血清25(OH)D,使用超声骨密度仪测定肱骨骨密度。采用Pearson相关分析法分析25(OH)D与体质量指数标准差得分(BMISDS)、腰臀比、胰岛素、骨密度、甲状旁腺激素(PTH)的相关性。结果肥胖组儿童身高、体质量、体质量指数(BMI)、BMISDS、腰围、腰臀比均明显高于对照组〔身高(cm):140.99±8.79比134.59±10.13,体质量(kg):51.14±15.96比28.06±6.00,BMI(kg/m2):25.14±4.02比15.56±1.51,BMISDS:2.89±0.97比-0.44±0.80,腰围(cm):89.95±12.44比58.99±6.24,腰臀比:0.98±0.08比0.85±0.05,均P<0.05〕,血清25(OH)D和骨密度均明显低于对照组〔25(OH)D(nmol/L):45.40±11.86比59.56±16.08,骨密度(g/m2):2.91±1.68比3.75±1.15,均P<0.05〕,胰岛素明显高于对照组(μg/L:25.57±7.98比14.03±3.00,P<0.05);两组PTH比较差异无统计学意义。血清25(OH)D水平与BMISDS、腰臀比、腰围呈负相关(r值分别为-0.996、-0.999、-0.467,P值分别为0.000、0.001、0.000),而与胰岛素、PTH、骨密度无明显相关性。结论肥胖儿童25(OH)D和骨密度水平均较正常儿童低,血清25(OH)D水平与肥胖具有相关性。

关键词：肥胖儿童 25-羟基维生素D 骨密度

在线全文

学校读者我要写书评

暂无评论

苹果糖度近红外光谱检测的初步试验研究

中国食品学报 2005年第2期5卷 103-107页

作者：傅霞萍应义斌刘燕德浙江大学生物系统工程与食品科学学院杭州310029

应用近红外光谱漫反射技术,开展了苹果内部品质无损检测的研究。对试验结果的方差分析表明:苹果不同测量位置对光谱测量的影响不显著,而不同测量距离对光谱影响较显著。运用SPSS10.0统计软件对苹果糖度与光谱曲线波峰处对应的吸光度进... 详细信息

应用近红外光谱漫反射技术,开展了苹果内部品质无损检测的研究。对试验结果的方差分析表明:苹果不同测量位置对光谱测量的影响不显著,而不同测量距离对光谱影响较显著。运用SPSS10.0统计软件对苹果糖度与光谱曲线波峰处对应的吸光度进行多元线性回归分析,建立最佳单波长、最佳双波长组合、最佳三波长组合和最佳四波长组合的校正方程,相关系数R分别为0.621、0.675、0.797和0.822,标准校正误差(SEC)分别为1.75、1.65、1.34和1.27°Brix,相对校正误差(R SEC)分别为13.73%、12.96%、11.42%和10.81%,试验表明:利用近红外光谱技术无损检测苹果糖度等内部品质是可行性的,也为今后进一步建立水果内部品质预测模型奠定了基础。

关键词：苹果试验研究光谱检测糖度多元线性回归分析 SPSS10.0 近红外光谱技术内部品质无损检测波长组合校正误差方差分析表反射技术光谱测量测量位置试验结果测量距离光谱曲线统计软件校正方程相关系数预测模型

A 4H-SiC semi-super-junction shielded trench MOSFET: p-pillar is grounded to optimize the electric field characteristics

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2022年第12期43卷 79-87页

作者： Xiaojie Wang Zhanwei Shen Guoliang Zhang Yuyang Miao Tiange Li Xiaogang Zhu Jiafa Cai Rongdun Hong xiaping Chen Dingqu Lin Shaoxiong Wu Yuning Zhang Deyi fu Zhengyun Wu Feng Zhang College of Physical Science and Technology Xiamen UniversityXiamen 361005China Key Laboratory of Semiconductor Material Sciences Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Shenzhen Research Institute of Xiamen University Shenzhen 518057China Jiujiang Research Institute of Xiamen University Jiujiang 332000China

A 4H-SiC trench gate metal-oxide-semiconductor field-effect transistor(UMOSFET)with semi-super-junction shiel-ded structure(SS-UMOS)is proposed and compared with conventional trench MOSFET(CT-UMOS)in this *** advantage of the proposed structure is given by comprehensive study of the mechanism of the local semi-super-junction structure at the bottom of the trench *** particular,the influence of the bias condition of the p-pillar at the bottom of the trench on the static and dynamic performances of the device is compared and *** on-resistance of SS-UMOS with grounded(G)and ungrounded(NG)p-pillar is reduced by 52%(G)and 71%(NG)compared to CT-UMOS,***,gate ox-ide in the GSS-UMOS is fully protected by the p-shield layer as well as semi-super-junction structure under the trench and p-base ***,a reduced electric-field of 2 MV/cm can be achieved at the corner of the p-shield ***,the quasi-intrinsic protective layer cannot be formed in NGSS-UMOS due to the charge storage effect in the floating p-pillar,resulting in a large electric field of 2.7 MV/cm at the gate oxide ***,the total switching loss of GSS-UMOS is 1.95 mJ/cm2 and is reduced by 18%compared with *** the contrary,the NGSS-UMOS has the slowest overall switching speed due to the weakened shielding effect of the p-pillar and the largest gate-to-drain capacitance among the *** proposed GSS-UMOS plays an important role in high-voltage and high-frequency applications,and will provide a valuable idea for device design and circuit applications.

关键词： breakdown voltage specific on-resistance silicon carbide switching energy loss super-junction-shield(SS) trench gate MOSFET grounded(G) ungrounded(NG)