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Printed circuit board solder joint quality inspection based on lightweight classification network

IET Cyber-Systems and Robotics 2023年第4期5卷 27-39页

作者： Zhicong zhang Wenyu Zhang Donglin Zhu Yi Xu Changjun Zhou College of Science Dalian Minzu UniversityDalianChina Department of Information Science and Engineering Ocean University of ChinaQingdaoChina College of Mathematics and Computer Science Zhejiang Normal UniversityJinhuaChina

Solder joint quality inspection is a crucial step in the qualification inspection of printed circuit board(PCB)components,and efficient and accurate inspection methods will greatly improve its production efficiency.In this paper,we propose a PCB solder joint quality detection algorithm based on a lightweight classification network.First,the Select Joint segmentation method was used to obtain the solder joint information,and colour space conversion was used to locate the solder joint.The mask method,contour detection,and box line method were combined to complete the extraction of solder joint information.Then,by combining the respective characteristics of convolutional neural network and Transformer and introducing Cross-covariance attention to reduce the computational complexity and resource consumption of the model and evenly distribute the global view mutual information in the whole training process,a new lightweight network model MobileXT is proposed to complete defect classification.Only 16.4%of the Vision Transformer computing resources used in this model can achieve an average accuracy improvement of 31%.Additionally,the network is trained and validated using a dataset of 1804 solder joint images constructed from 93 PCB images and two external datasets to evaluate MobileXT performance.The proposed method achieves more effi-cient localization of the solder joint information and more accurate classification of weld joint defects,and the lightweight model design is more appropriate for industrial edge device deployments.

关键词： convolutional neural network deep learning neural network-based

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磁学与热电学的交叉探索

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Science Bulletin 2022年第9期67卷 891-894,M0003页

作者： Cuncheng Li wenyu Zhao Qingjie zhang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Thermoelectrics have important applications in power generation and refrigeration through the direct energy conversion between heat and electricity.The performance of thermoelectric(TE)materials can be qualified by dimensionless figure of merit ZT=σa2/κ,whereσ,a andκare the electrical conductivity,Seebeck coefficient and thermal conductivity,respectively.

关键词： conductivity Seebeck electrical

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A dual-mode fiber-shaped flexible capacitive strain sensor fabricated by direct ink writing technology for wearable and implantable health monitoring applications

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Microsystems & Nanoengineering 2023年第6期9卷 321-331页

作者： Chi zhang wenyu Ouyang Lei zhang Dachao Li State Key Laboratory of Precision Measuring Technology and Instruments Tianjin University300072 TianjinChina

Flexible fiber-shaped strain sensors show tremendous potential in wearable health monitoring and human‒machine interactions due to their compatibility with everyday clothing.However,the conductive and sensitive materials generated by traditional manufacturing methods to fabricate fiber-shaped strain sensors,including sequential coating and solution extrusion,exhibit limited stretchability,resulting in a limited stretch range and potential interface delamination.To address this issue,we fabricate a fiber-shaped flexible capacitive strain sensor(FSFCSS)by direct ink writing technology.Through this technology,we print parallel helical Ag electrodes on the surface of TPU tube fibers and encapsulate them with a high dielectric material BTO@Ecoflex,endowing FSFCSS with excellent dual-mode sensing performance.The FSFCSS can sense dual-model strain,namely,axial tensile strain and radial expansion strain.For axial tensile strain sensing,FSFCSS exhibits a wide detection range of 178%,a significant sensitivity of 0.924,a low detection limit of 0.6%,a low hysteresis coefficient of 1.44%,and outstanding mechanical stability.For radial expansion strain sensing,FSFCSS demonstrates a sensitivity of 0.00086 mmHg−1 and exhibits excellent responsiveness to static and dynamic expansion strain.Furthermore,FSFCSS was combined with a portable data acquisition circuit board for the acquisition of physiological signals and human‒machine interaction in a wearable wireless sensing system.To measure blood pressure and heart rate,FSFCSS was combined with a printed RF coil in series to fabricate a wireless hemodynamic sensor.This work enables simultaneous application in wearable and implantable health monitoring,thereby advancing the development of smart textiles.

关键词： wear strain shaped

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Origination and evolution of orphan genes and de novo genes in the genome of Caenorhabditis elegans

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Science China(Life Sciences) 2019年第4期62卷 579-593页

作者： Wenyu Zhang Yuanxiao Gao Manyuan Long Bairong Shen Institutes for Systems Genetics West China Hospital Sichuan University Department of Ecology and Evolution the University of Chicago Department of Evolutionary Genetics Max-Planck Institute for Evolutionary Biology Department of Evolutionary Theory Max-Planck Institute for Evolutionary Biology Committee on Genetics the University of Chicago

Orphan genes that lack detectable homologues in other lineages could contribute to a variety of biological functions. However,their origination and function mechanisms remain largely unknown. Herein, through a comprehensive and systematic computational pipeline, we identified 893 orphan genes in the lineage of C. elegans, of which only a low fraction(0.9%) were derived from transposon elements. Six new protein-coding genes that de novo originated from non-coding DNA sequences in the genome of C. elegans were also identified. The authenticity and functionality of these orphan genes and de novo genes are supported by three lines of evidences, consisting of transcriptional data, and in silico proteomic data, and the fixation status data in wild populations. Orphan genes and de novo genes exhibited simple gene structures, such as, short in protein length, of fewer exons,and are frequently X-linked. RNA-seq data analysis showed these orphan genes are enriched with expression in embryo development and gonad, and their potential function in early development was further supported by gene ontology enrichment analysis results. Meanwhile, de novo genes were found to be with significant expression in gonad, and functional enrichment analysis of the co-expression genes of these de novo genes suggested they may be functionally involved in signaling transduction pathway and metabolism process. Our results presented the first systematic evidence on the evolution of orphan genes and de novo origin of genes in nematodes and their impacts on the functional and phenotypic evolution, and thus could shed new light on our appreciation of the importance of these new genes.

关键词： Caenorhabditis elegans,orphan genes de novo genes

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Satellite Navigation Method Based on High-Speed Frequency Hopping Signal

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China Communications 2023年第7期20卷 321-337页

作者： En Yuan Peng Liu Weiwei Chen Rui Wang Bing Xu Wenyu Zhang Yanqin Tang Command&Control Engineering College Army Engineering University of PLANanjing 210007China

Global navigation satellite system has been widely used,but it is vulnerable to jamming.In military satellite communications,frequency hopping(FH)signal is usually used for anti-jamming communications.If the FH signal can be used in satellite navigation,the anti-jamming ability of satellite navigation can be improved.Although a recently proposed timefrequency matrix ranging method(TFMR)can use FH signals to realize pseudorange measurement,it cannot transmit navigation messages using the ranging signal which is crucial for satellite navigation.In this article,we propose dual-tone binary frequency shift keyingbased TFMR(DBFSK-TFMR).DBFSK-TFMR designs an extended time-frequency matrix(ETFM)and its generation algorithm,which can use the frequency differences in different dual-tone signals in ETFM to modulate data and eliminate the negative impact of data modulation on pseudorange measurement.Using ETFM,DBFSK-TFMR not only realizes the navigation message transmission but also ensures the precision and unambiguous measurement range of pseudorange measurement.DBFSK-TFMR can be used as an integrated solution for anti-jamming communication and navigation based on FH signals.Simulation results show that DBFSK-TFMR has almost the same ranging performance as TFMR.

关键词： satellite navigation frequency hopping ranging navigation message transmission

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Efficient nitrite-to-ammonia electroreduction over Zr-Ni frustrated Lewis acid-base pairs

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Science China Chemistry 2024年第5期67卷 1707-1714页

作者： Ying zhang Zhuohang Li wenyu Du Kai Chen Ke Chu School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

Electrochemical NO_(2)~--to-NH_(3) conversion(NO_(2)RR) offers a green route to NH_(3) electrosynthesis, while developing efficient NO_(2)RR catalysis systems at high current densities remains a grand challenge. Herein, we report an efficient Zr-NiO catalyst with atomically dispersed Zr-dopants incorporated in NiO lattice, delivering the exceptional NO_(2)RR performance with industriallevel current density(>0.2 A cm^(-2)). In situ spectroscopic measurements and theoretical simulations reveal the construction of ZrNi frustrated Lewis acid-base pairs(FLPs) on Zr-Ni O, which can substantially increase the number of absorbed nitrite(NO_(2)~-),promote the activation and protonation of NO_(2)~- and concurrently hamper the H coverage, boosting the activity and selectivity of Zr-NiO towards the NO_(2)RR. Remarkably, Zr-NiO exhibits the exceptional performance in a flow cell with high Faradaic efficiency for NH_(3) of 94.0% and NH_(3)yield rate of 1,394.1 μmol h^(-1)cm^(-2) at an industrial-level current density of 228.2 m A cm^(-2),placing it among the best NO_(2)RR electrocatalysts for NH_(3) production.

关键词： electrochemical nitrite-to-ammonia conversion frustrated Lewis acid-base pairs(FLPs) in situ spectroscopy theoretical computations

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Development and application of the multi-wavelength cavity ring-down aerosol extinction spectrometer

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Journal of Environmental Sciences 2019年第2期31卷 227-237页

作者： Junling Li Weigang Wang Kun Li Wenyu Zhang Maofa Ge Chao Peng State Key Laboratory for Structural Chemistry of Unstable and Stable Species CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences University of Chinese Academy of Sciences Air Quality Research Division Environment and Climate Change Canada Center for Excellence in Urban Atmospheric Environment (CEUAE) Institute of Urban EnvironmentChinese Academy of Sciences

To better characterize the optical properties of atmospheric aerosols, the multi-wavelength cavity ring-down aerosol extinction spectrometer(MCRD-AES) is developed and applied in this study. By using tunable light source and four parallel cavities, the MCRD-AES covers a wide and atmospherically relevant wavelength range from 360 to 663 nm. Four wavelengths(375 nm, 440 nm, 532 nm, and 620 nm) are particularly tested with ammonium sulfate and nigrosine. The refractive index values obtained from this study agree well with literature data. The stability and accuracy of the MCRD-AES are tested, and the minimum detectable extinction coefficient is 0.5 1/Mm. The high sensitivity, high precision, and wavelength changeable of MCRD-AES indicate its great application prospect in comprehensively quantifying the optical properties of atmospheric aerosols.

关键词： MCRD-AES Optical property Refractive indices Wavelength dependence

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Investigation of carbonyl amidation and O-methylation during biosynthesis of the pharmacophore pyridyl of antitumor piericidins

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Synthetic and Systems Biotechnology 2022年第3期7卷 880-886页

作者： Wanlu Li Wenyu Zhang Yijia Cheng Yaoyao Shen Jianzhao Qi Hou-Wen Lin Yongjun Zhou Research Center for Marine Drugs State Key Laboratory of Oncogenes and Related GenesDepartment of PharmacyRen Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai200127China Shaanxi Key Laboratory of Natural Products&Chemical Biology College of Chemistry&PharmacyNorthwest A&F UniversityYangling712100ShaanxiChina

Piericidins are a large family of bacterialα-pyridone antibiotics with antitumor activities such as their anti-renal carcinoma activity exhibited recently in nude mice.The backbones of piericidins are derived fromβ,δ-diketo carboxylic acids,which are offloaded from a modular polyketide synthase(PKS)and putatively undergo a carbonyl amidation beforeα-pyridone ring formation.The tailoring modifications to theα-pyridone structure mainly include the verified hydroxylation and O-methylation of the C-4′position and an unidentified C-5′O-methylation.Here,we describe a piericidin producer,terrestrial Streptomyces conglobatus,which contains a piericidin biosynthetic gene cluster in two different loci.Deletion of the amidotransferase gene pieD resulted in the accumulation of two fatty acids that should be degraded from the nascent carboxylic acid released by the PKS,supporting the carbonyl amidation function of PieD duringα-pyridone ring formation.Deletion of the O-methyltransferase gene pieB1 led to the production of three piericidin analogues lacking C-5′O-methylation,therefore confirming that PieB1 specifically catalyses the tailoring modification.Moreover,bioactivity analysis of the mutant-derived products provided clues regarding the structure-function relationship for antitumor activity.The work addresses two previously unidentified steps involved in pyridyl pharmacophore formation during piericidin biosynthesis,facilitating the rational bioengineering of the biosynthetic pathway towards valuable antitumor agents.

关键词： Polyketide Pyridine Polyketide synthase(PKS) Natural product biosynthesis

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Bayesian machine learning-based method for prediction of slope failure time

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第4期14卷 1188-1199页

作者： Jie zhang Zipeng Wang Jinzheng Hu Shihao Xiao wenyu Shang Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education Tongji UniversityShanghai200092China Department of Geotechnical Engineering Tongji UniversityShanghai200092China Natural Science College Michigan State UniversityMI48825USA

The data-driven phenomenological models based on deformation measurements have been widely utilized to predict the slope failure time(SFT).The observational and model uncertainties could lead the predicted SFT calculated from the phenomenological models to deviate from the actual SFT.Currently,very limited study has been conducted on how to evaluate the effect of such uncertainties on SFT prediction.In this paper,a comprehensive slope failure database was compiled.A Bayesian machine learning(BML)-based method was developed to learn the model and observational uncertainties involved in SFT prediction,through which the probabilistic distribution of the SFT can be obtained.This method was illustrated in detail with an example.Verification studies show that the BML-based method is superior to the traditional inverse velocity method(INVM)and the maximum likelihood method for predicting SFT.The proposed method in this study provides an effective tool for SFT prediction.

关键词： Slope failure time(SFT) Bayesian machine learning(BML) Inverse velocity method(INVM)

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Voluntary wheel running ameliorated the deleterious effects of high-fat diet on glucose metabolism,gut microbiota and microbial-associated metabolites

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Food Science and Human Wellness 2024年第3期13卷 1672-1684页

作者： Ling zhang wenyu Zou Yongyan Hu Honghua Wu Ying Gao Junqing zhang Jia Zheng Department of Endocrinology Peking University First HospitalBeijing 100034China Laboratory Animal Facility Peking University First HospitalBeijing 100034China

Exercise training is critical for the early prevention and treatment of obesity and diabetes mellitus.However,the mechanism with gut microbiota and fecal metabolites underlying the effects of voluntary wheel running on high-fat diet induced abnormal glucose metabolism has not been fully elaborated.C57BL/6 male mice were randomly assigned to 4 groups according to diets(fed with normal chow diet or high-fat diet)and running paradigm(housed in static cage or with voluntary running wheel).An integrative 16S rDNA sequencing and metabolites profiling was synchronously performed to characterize the effects of voluntary wheel running on gut microbiota and metabolites.It showed that voluntary wheel running prevented the detrimental effects of high-fat feeding on glucose metabolism 16S rDNA sequencing showed remarkable changes in Rikenella and Marvinbryantia genera.Metabolic profiling indicated multiple altered metabolites,which were enriched in secondary bile acid biosynthesis signaling.In conclusion,our study indicated that voluntary wheel running significantly improved glucose metabolism and counteracted the deleterious effects of high-fat feeding on body weight and glucose intolerance.We further found that voluntary wheel running could integratively program gut microbiota composition and fecal metabolites changes,and may regulate muricholic acid metabolism and secondary bile acid biosynthesis in high-fat fed mice.

关键词： High-fat diet Voluntary wheel running Gut microbiota Metabolomics Glucose metabolism

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