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Identification of various food residuals on denim based on hyperspectral imaging system and combination optimal strategy

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Artificial Intelligence in Agriculture 2021年第1期5卷 125-132页

作者： Yuzhen Chen Ziyi Xu wencheng tang Menghan Hu Douning tang Guangtao Zhai Qingli Li Shanghai Key Laboratory of Multidimensional Information Processing School of Communication&Electronic EngineeringEast China Normal UniversityShanghai 200062China School of Statistics East China Normal UniversityShanghai 200062China Institute of Image Communication and Information Processing Shanghai Jiao Tong UniversityShanghai 200240China McCormick School of Engineering Northwestern UniversityEvanstonILUnited States

As the science and technology develop,crime methods and scenes have become increasingly complex and *** evidence analysis has become amore and more important criminal investigation technology and liquid is the main form of trace *** can provide not only energy,but clues to solve *** this study,we build a hyperspectral imaging system to detect liquid residue traces,including apple juice,coffee,cola,milk and tea,on denims with light,middle and dark *** obtained hyperspectral images are first subjected to spectral calibration and hyperspectral data ***,Partial Least Squares(PLS)is applied to select the informative wavelengths from the preprocessed *** modeling phase,the combination optimal strategy,support vector machine(SVM)combined with random forest(RF),is developed to establish classification *** experimental results demonstrate that the combination optimal model can achieve TPR,FPR,Precision,Recall,F1,and AUC of 83.5%,2.30%,79.7%,83.5%,81.6%,and 94.7%for classifying fabrics contaminated by various food *** respect to the classification of liquid and fabric types,the combination optimalmodel also yields satisfactory classification *** future work,wewill expand the types of liquid,and make appropriate adjustment to algorithms for improving the robustness of classification *** research may play a positive role in the construction of a harmonious society.

关键词： Hyperspectral imaging Food residual on denim Combination optimal strategy Variable selection Forensic application

Nickel accumulation and its effects on the survival rate of Spodoptera litura Fabricius under continuous nickel stress

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Chinese Science Bulletin 2007年第14期52卷 1957-1963页

作者： SUN HongXia SHU YingHua tang wencheng WANG Qi ZHOU Qiang ZHANG GuRen State Key Laboratory for Biological Control & Institute of Entomology Sun Yat-sen University Guangzhou 510275 China

The artificial diets mixed with various concentrations of nickel were offered to the larvae of the phytophagous insect Spodoptera litura Fabricius for 3 generations. Nickel accumulations in the 6th instar larvae, pupae and newly emerged adults of the corresponding generations of S. litura were investigated by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), and the effects of nickel accumulations on the survival rate of S. litura were also evaluated by individual rearing. The results showed that nickel accumulated in the 6th instar larvae, pupae and adults of S. litura, and the accu- mulated nickel in all the tested developmental stages within a generation increased with the increase of the nickel doses in the treated diets and showed significant dose-dependent relationship with the nickel doses in the artificial diets. The results also indicated that the nickel accumulations in the 6th instar larvae, pupae, and newly emerged adults from the 3rd generation were higher than those from the 2nd generation, which were also higher than those from the 1st generation. Nickel concentrations in pupae and adults were significantly lower than those in larvae, which indicated that the excessive nickel might be excreted during metamorphosis. Furthermore, larval survival rate, pupation rate and eclosion rate of S. litura in the tested three generations all decreased with the increase of the nickel doses in the treated diets.

关键词：镍蓄积重金属昆虫食草动物

Metallothionein expression induced by nickel accumulation in the midgut of Spodoptera litura Fabricius larvae exposed to nickel

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Chinese Science Bulletin 2007年第23期52卷 3227-3232页

作者： SUN HongXia ZHOU Qiang tang wencheng SHU YingHua ZOU ZhiWen ZHANG GuRent State key laboratory for Biological Control & Institute of Entomology Sun Yat-sen University Guangzhou 510275 China

Metallothionein expression induced by nickel accumulation in the midgut of Spodoptera litura Fabri- cius larvae was investigated by exposing S. litura larvae to the artificial diets amended with different doses of nickel for 3 generations. Nickel accumulations in the midgut of 6th instar larvae were detected by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), and the induced metal- lothionein expression in the midgut of 5th and 6th instar larvae in 120 h were quantified using cad- mium-hemoglobin total saturation methods. The accumulated nickel in the midgut of the 6th instar larvae within a generation increased with the increase of the nickel doses in the treated diets and showed significant dose-dependence with the nickel doses in diets. Metallothioneins induced by nickel accumulated in the larval midgut also increased with nickel doses in diets and with the increasing stressing time in a generation. Results also suggested that the metallothionein expression was differ- ent with the time of S. litura larvae stressed by nickel.

关键词：镍元素亲金属蛋白质中肠物质积累

A method for constraining the end effect of EMD based on sequential similarity detection and adaptive filter

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Journal of Southeast University(English Edition) 2021年第1期37卷 14-21页

作者： Wei Dongdong tang wencheng School of Mechanical Engineering Southeast UniversityNanjing 211189China

Aimed at the problem of the end effect when using empirical mode decomposition(EMD),a method for constraining the end effect of EMD is proposed based on sequential similarity detection and adaptive *** method divides the signal into many wavelets,and it changes the initial wavelet length to select the best initial wavelet that has the minimum error and maximum number of matching seed wavelets,and the wavelet slopes are used for pre-matching and secondary matching to speed up the matching ***,folded self-adaptive threshold is used to select multiple seed wavelets,and finally the end waveform is predicted and expanded according to the adaptive filter *** proposed method is used to analyze the non-stationary nonlinear simulation signal and experimental signal,and it is compared with the mirror extension and RBF extension *** orthogonality index and similarity index of the EMD results of the extended signal after the proposed method are better than those of the other *** results show that the proposed method can better constrain the end effect,and has certain validity,accuracy and stability in solving the end effect problem.

关键词： empirical mode decomposition(EMD) end effect sequential similarity detection adaptive filter

Effects of dietary nickel on apoptosis of hemocytes of Spodoptera litura (Fabricius) larvae

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Chinese Science Bulletin 2010年第23期55卷 390-397页

作者： SUN HongXia Xia Qiang tang wencheng ZHOU Qiang ZHANG GuRen DANG Zhi The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of Education & School of Environmental Science and Engineering South China University of Technology Guangzhou 510006 China State Key Laboratory for Biological Control & Institute of Entomology Sun Yat-sen University Guangzhou 510275 China Zhuhai Campus Zunyi Medical College Zhuhai 519041 China

Effects of dietary nickel on apoptosis of hemocytes of the 6th instar larvae of Spodoptera litura Fabricius were evaluated using flow cytometry and Laser Scanning Confocal Microscopy (LSCM) by feeding S. litura larvae with artificial diets amended with different concentrations of nickel (1, 5, 10, 20 and 40 mg/kg) for 3 generations. Results showed that the hemocyte apoptosis rate of the 1st generation larvae increased with the increasing nickel concentrations in diet, and the apoptosis rate in the treatment with 40 mg/kg nickel was significantly higher than that in other treatments. In the 2nd generation, the highest hemocytes apoptosis rate was recorded in the treatment of the larvae exposed to 5 mg/kg nickel. The apoptosis rates in the larvae stressed by higher concentrations of nickel were lower than that in control. The apoptosis rates in the larvae exposed to nickel for 3 generations showed similar concentration-responses with that in the 2nd generation. However, the apoptosis rates in the larvae stressed with higher levels of nickel were all significantly inhibited in comparison with that in control. Therefore, effects of nickel stress on apoptosis of S. litura larvae were related with the nickel concentration in diets and the larval generations that were stressed by nickel.

关键词：斜纹夜蛾幼虫细胞凋亡镍含量饮食激光扫描共聚焦显微镜作者流式细胞仪口服补液盐

Mapping relationship analysis of welding assembly properties for thin-walled parts with finite element and machine learning algorithm

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Journal of Southeast University(English Edition) 2022年第2期38卷 126-136页

作者： Pan Minghui Liao Wenhe Xing Yan tang wencheng School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Digital Forming Technology and Equipment National-Local United Engineering Laboratory Nanjing University of Science and Technology Nanjing 210094 China School of Mechanical Engineering Southeast University Nanjing 211189 China

The finite element(FE)-based simulation of welding characteristics was carried out to explore the relationship among welding assembly properties for the parallel T-shaped thin-walled parts of an antenna *** effects of welding direction,clamping,fixture release time,fixed constraints,and welding sequences on these properties were analyzed,and the mapping relationship among welding characteristics was thoroughly *** machine learning algorithms,including the generalized regression neural network(GRNN),wavelet neural network(WNN),and fuzzy neural network(FNN),are used to predict the multiple welding properties of thin-walled parts to mirror their variation trend and verify the correctness of the mapping *** with those from GRNN and WNN,the maximum mean relative errors for the predicted values of deformation,temperature,and residual stress with FNN were less than 4.8%,1.4%,and 4.4%,*** results indicate that FNN generated the best predicted welding *** under various welding conditions also shows a mapping relationship among welding deformation,temperature,and residual stress over a period of *** finding further provides a paramount basis for the control of welding assembly errors of an antenna structure in the future.

关键词： parallel T-shaped thin-walled parts welding assembly property finite element analysis mapping relationship machine learning algorithm

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复合材料网格结构模态分析的均匀化等效建模

复合材料学报 2008年第2期25卷 188-193页

作者：魏志刚汤文成东南大学机械工程学院南京211189

复合材料网格结构由于内部结构复杂,在有限元分析中难以建立实际模型,需要对结构采用均匀化方法进行弹性常数等效。本文中根据结构的最小势能原理和有限元法基本思想,对结构的弹性力学基本方程进行了推导,使用有限单元法中的位移场,根... 详细信息

复合材料网格结构由于内部结构复杂,在有限元分析中难以建立实际模型,需要对结构采用均匀化方法进行弹性常数等效。本文中根据结构的最小势能原理和有限元法基本思想,对结构的弹性力学基本方程进行了推导,使用有限单元法中的位移场,根据应变能相等的原则,得出了求解等效弹性矩阵的一种比较通用的方法;根据动能相等的原则,得出了等效质量的求解公式。采用有限元方法,对胞元进行了拉伸和剪切载荷下的细观力学分析,将分析结果代入到推导的公式,求出了复合材料网格结构的等效特性参数;使用求得的等效模型对结构进行了宏观仿真,并与实际模型仿真结果进行对比。研究结果表明,该等效方法具有较好的精度,能够满足工程的需要,可用于各类大型结构的分析。

关键词：复合材料网格结构弹性常数模态均匀化

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双弯曲反射面天线卧立转换尺寸偏差分析方法

机械工程学报 2015年第17期51卷 120-127页

作者：倪俊汤文成幸研东南大学机械工程学院南京211189

针对包含数千铆钉的双弯曲反射面天线装配尺寸精度计算问题,提出一种卧立转换尺寸偏差回弹分析方法:以动力学有限元模型表示一组铆接工艺参数(铆钉和局部板件尺寸、材料参数、辅助装夹位置、铆钉镦粗方向,冲头位移规律);完成动力学有限... 详细信息

针对包含数千铆钉的双弯曲反射面天线装配尺寸精度计算问题,提出一种卧立转换尺寸偏差回弹分析方法:以动力学有限元模型表示一组铆接工艺参数(铆钉和局部板件尺寸、材料参数、辅助装夹位置、铆钉镦粗方向,冲头位移规律);完成动力学有限元计算,得到的铆钉孔周固有变形分布,不难发现,孔周固有变形分布与铆接工艺参数存在明确的对应关系;经空间插值,为薄壁部件静力学有限元代码中每个铆钉孔加载铆钉孔周固有变形和已计算出的变形,实现铆接变形作用下的结构装配尺寸偏差分析。以纯动力学有限元计算结果验证方法准确性。以大尺寸薄壁部件为对象,研究零件重力和铆接变形所导致的装配尺寸偏差在卧立转换前后的回弹效应。

关键词：铆钉装配偏差回弹

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基于动态拘束的法兰片焊接变形数值模拟

焊接学报 2020年第12期41卷 67-73,I0005页

作者：王晨曦汤文成东南大学先进制造国家重点实验室南京211189

外拘束对焊接变形的影响较大,是影响焊接变形的重要因素之一.相比于传统的刚性拘束,动态拘束能够实时的反映外拘束力在焊接过程中的变化效果.在两条焊缝多层多道交叉焊的情况下,建立多场耦合分析模型,利用弹簧单元模拟较低刚度夹具的变... 详细信息

外拘束对焊接变形的影响较大,是影响焊接变形的重要因素之一.相比于传统的刚性拘束,动态拘束能够实时的反映外拘束力在焊接过程中的变化效果.在两条焊缝多层多道交叉焊的情况下,建立多场耦合分析模型,利用弹簧单元模拟较低刚度夹具的变形所带来的动态拘束力效果,考虑了变形量对于拘束力的反馈.从拘束刚度、拘束距离、初始拘束力以及拘束宽度4个因素来探讨焊件的变形情况,得出各因素下的变形规律,并利用回归分析对4个因素进行综合评价.结果表明,4个拘束因素的增加都能不同程度的减小变形量,拘束刚度、拘束初始力、拘束宽度的影响趋势较为相似,且拘束初始力影响最大,拘束距离在其范围内影响趋势为线性,且影响性最小.

关键词：焊接变形多层多道焊动态拘束回归分析