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基于机器视觉的线束连接器字符检测

测试技术学报 2018年第2期32卷 174-179页

作者：吴晖辉曾宪荣赖燕君吴福培顺德职业技术学院机电工程学院广东佛山528330 汕头大学机械电子工程系广东汕头515063

针对线束连接器上印刷字符检测智能化程度不高的情况,提出了一种基于机器视觉的检测方法.首先,利用一阶导数获得印刷字符边缘点,并将边缘点拟合为线,由此定位字符的位置,并对字符的角度和位置进行比较;然后,对合格的字符分割、归一化,... 详细信息

针对线束连接器上印刷字符检测智能化程度不高的情况,提出了一种基于机器视觉的检测方法.首先,利用一阶导数获得印刷字符边缘点,并将边缘点拟合为线,由此定位字符的位置,并对字符的角度和位置进行比较;然后,对合格的字符分割、归一化,并以整个字符图像作为输入特征;最后,基于字符的特征,建立了用于印刷字符识别的BP神经网络,并对其进行了改进.实验证明:基于机器视觉的连接器印刷字符单个字符识别准确率为99.1%,检测时间为95ms,具有较高的识别准确率和速度.

关键词：机器视觉线束连接器字符检测神经网络

MMP-9、MMP-2及TLR4、HE4对非小细胞肺癌早期诊断意义

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中华肺部疾病杂志（电子版） 2024年第5期17卷 756-761页

作者：梁丽斯李洁贺帅来艳君刘铭张琳西安市第九医院检验科西安710054 西安市第九医院呼吸与危重症医学科西安710054

目的分析血清基质金属蛋白酶9(matrix metalloproteinases-9,MMP-9)、基质金属蛋白酶2(matrix metalloproteinase 2,MMP-2)及Toll样受体4(toll-like receptor 4,TLR4)、人附睾蛋白4(human epididymis protein 4,HE4)用于非小细胞肺癌(non-small cell lung carcinoma,NSCLC)早期诊断的意义。方法收集2021年1月至2023年12月我院收治的35例NSCLC患者为观察组,选取同期住院肺部良性病变患者39例为对照组。比较两组血清MMP-9、MMP-2、TLR4、HE4水平,比较不同临床病理特征NSCLC患者的血清MMP-9、MMP-2、TLR4、HE4水平。通过受试者工作特征曲线(ROC)分析血清MMP-9、MMP-2、TLR4、HE4单项对NSCLC诊断,采取多因素Logistic回归性分析血清MMP-9、MMP-2及TLR4、HE4与NSCLC的相关性。结果观察组MMP-9、MMP-2、TLR4、HE4水平[(288.71±92.33)μg/L、(44.46±5.62)pg/ml、(5.30±1.24)ng/ml、(228.76±60.83)pmol/L]高于对照组[(214.66±45.89)μg/L、(20.15±4.03)pg/ml、(2.58±0.84)ng/ml、(57.76±18.14)pmol/L](P<0.05)。TNM分期Ⅲ~Ⅳ期、低分化、淋巴结转移的NSCLC患者血清MMP-9、MMP-2、TLR4、HE4水平高于TNM分期Ⅰ~Ⅱ期、中高分化、无淋巴结转移的NSCLC患者(P<0.05)。经ROC分析,血清MMP-9、MMP-2、TLR4、HE4单项诊断NSCLC的曲线下面积为0.790(95%CI:0.690~0.890)、0.804(95%CI:0.703~0.904)、0.813(95%CI:0.715~0.912)、0.817(95%CI:0.720~0.914),敏感性为0.650(95%CI:0.596~0.712)、0.800(95%CI:0.724~0.870)、0.750(95%CI:0.689~0.834)、0.775(95%CI:0.703~0.852),特异性为0.825(95%CI:0.763~0.884)、0.750(95%CI:0.688~0.825)、0.825(95%CI:0.778~0.871)、0.800(95%CI:0.734~0.846);血清MMP-9、MMP-2、TLR4、HE4联合诊断NSCLC的曲线下面积为0.953(95%CI:0.912~0.993),敏感性为0.850(95%CI:0.782~0.913),特异性为0.925(95%CI:0.862~0.979)。多因素Logistic回归分析显示,MMP-9≥237.465μg/L(OR=2.587,95%CI:1.241~5.393)、MMP-2≥29.115 pg/ml(OR=3.129,95%CI:1.336~7.328)、TLR4≥3.870 ng/ml(OR=3.202,95%CI:1.411~7.266)、HE4≥128.030 pmol/L(OR=3.415,95%CI:1.508~7.734)是NSCLC发生的危险因素(P<0.05)。结论血清MMP-9、MMP-2及TLR4、HE4对NSCLC具有诊断意义。

关键词：非小细胞肺癌基质金属蛋白酶9 基质金属蛋白酶2 Toll 样受体4 人附睾蛋白4 诊断

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杉木胶合木湿应力研究

林业工程学报 2019年第4期4卷 35-40页

作者：岳孔宋旭磊程秀才赖延军贾翀陆伟东刘伟庆南京工业大学土木工程学院南京211800 南京市产品质量监督检验院南京210019 南京林业大学材料科学与工程学院南京210037

为揭示环境湿度变化引起的木材含水率非均匀性分布对胶合木构件内部湿应力的影响规律,从材料层面测试了变湿度条件下290个国产杉木木材的平衡含水率,以及横纹径向和横纹弦向干缩性、湿胀性、水分扩散系数、抗拉强度和弹性模量等物理力... 详细信息

为揭示环境湿度变化引起的木材含水率非均匀性分布对胶合木构件内部湿应力的影响规律,从材料层面测试了变湿度条件下290个国产杉木木材的平衡含水率,以及横纹径向和横纹弦向干缩性、湿胀性、水分扩散系数、抗拉强度和弹性模量等物理力学性能参数,并从理论层面利用有限元模拟分析周期性变湿度条件下层板厚度对杉木胶合木湿应力的影响。研究结果表明:利用Nelson方程能够较好地拟合变湿度中杉木的平衡含水率;杉木横纹径向干缩和湿胀性均小于横纹弦向,横纹径向水分扩散系数、抗拉强度和弹性模量均高于横纹弦向,这决定于横纹径向排列的木射线以及管胞径面壁上大量纹孔导致的实质物质减少的微观构造;减小层板厚度有助于降低胶合木湿应力,当层板厚度由40 mm降至20 mm时,构件内部最大湿应力降低19.32%,但其最大值仍高于木材横纹抗拉强度,湿应力的降低程度不足以避免构件的横纹开裂;木结构工程设计和应用中必须考虑其他有效的方法减小湿应力以避免木材横纹开裂。

关键词：杉木胶合木湿应力平衡含水率微观构造

High-speed optoelectronic devices

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Science China(Information Sciences) 2023年第5期66卷 5-27页

作者： Yi LUO Changzheng SUN Bing XIONG Jian WANG Zhibiao HAO yanjun HAN Hongtao LI lai WANG Beijing National Research Center for Information Science and Technology (BNRist) Department of Electronic Engineering Tsinghua University

High-speed optoelectronic devices are key components of modern fiber communication systems,and the backbone of information technology. In this paper, we present our work on high-speed devices over the past decades, including high-performance semiconductor lasers and integrated light sources, wideband electrooptic modulators, high saturation power photodetectors, and their applications in both fiber communications and microwave photonics. Gain-coupled distributed feedback(DFB) lasers were fabricated with high singlemode yield. Electroabsorption modulated lasers(EMLs) were demonstrated based on identical epitaxial layer integration scheme, including single channel 40 Gb/s EMLs, and 4 × 25 and 4 × 56 Gb/s EML arrays. Both In P and thin-film lithium niobate based low half-wave voltage electro-optic modulators with modulation bandwidth over 40 GHz were demonstrated. Back-illuminated modified uni-traveling-carrier photodetectors(MUTC-PDs) with high saturation power and bandwidth exceeding 100 GHz were developed. Applications of high-speed optoelectronic devices in fiber-optic links and sub-THz wave generation are presented.

关键词： optoelectronic devices semiconductor lasers optical modulators photodetectors integrated photonic circuits

Facile fabrication of ultrathin freestanding nanoporous Cu and Cu-Ag films with high SERS sensitivity by dealloying Mg-Cu(Ag)-Gd metallic glasses

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Journal of Materials Science & Technology 2021年第11期70卷 205-213页

作者： Yuan-Yun Zhao Feng Qian Chengliang Zhao Chunxiao Xie Jianguo Wang Chuntao Chang yanjun Li lai-Chang Zhang Neutron Scattering Technical Engineering Research Center School of Mechanical EngineeringDongguan University of TechnologyDongguan523808China Department of Materials Science and Engineering Norwegian University of Science and TechnologyTrondheim7491Norway Edith Cowan University School of Engineering270 Joondalup DriveJoondalupPerthWA6027Australia School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China

Nanoporous metals prepared by dealloying have attracted increasing attention due to their interesting size-dependent physical,chemical,and biological ***,facile fabrication of metallic ultrathin freestanding nanoporous films(UF-NPFs)by dealloying is still ***,we report a novel strategy of facile preparation of flexible Cu,Cu_(3)Ag,and CuAg UF-NPFs by dealloying thick Mg-Cu(Ag)-Gd metallic glass *** dealloying,the local reaction latent heat-induced glass transition of the precursor ribbons leads to the formation of a solid/liquid interface between the initially dealloyed nanoporous layer and the underlying supercooled liquid *** to the bulging effect of in situ generated H2 on the solid/liquid interface,Cu,Cu_(3)Ag,and CuAg UF-NPFs with thicknesses of~200 nm can self-peel off from the outer surface of the dealloying ***,it was found that the surfaceenhanced Raman scattering(SERS)detection limit of Rhodamine 6G(R6G)on the Cu and CuAg UF-NPF substrates are 10^(-6)M and 10^(-11)M,respectively,which are lower than most of the Cu and Cu-Ag substrates prepared by other *** work presents a reliable simple strategy to synthesize a variety of cost effective and flexible metallic UF-NPFs for functional applications.

关键词： Metallic glasses Dealloying Nanoporous metals Ultrathin freestanding films Surface-enhanced Raman scattering(SERS)

The mid-domain effect in flowering phenology

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Plant Diversity 2024年第4期46卷 502-509页

作者： yanjun Du Rongchen Zhang Xinran Tang Xinyang Wang Lingfeng Mao Guoke Chen Jiangshan lai Keping Ma School of Tropical Agriculture and Forestry(School of Agricultural and Rural Affairs School of Rural Revitalization)Hainan UniversityHaikou 570228China HNU-ASU Joint International Tourism College Hainan UniversityHaikou 570228China School of Ecological and Environmental Sciences East China Normal UniversityShanghai 200062China College of Ecology and Environment Nanjing Forestry UniversityNanjing 210037China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

The timing of flowering is an important driver of species distribution and community assembly ***,we still have much to learn about the factors that shape flowering diversity(i.e.,number of species flowering per period) in plant *** potential explanation of flowering diversity is the mid-domain effect,which states that geometric constraints on species ranges within a bounded domain(space or time) will yield a mid-domain peak in diversity regardless of ecological ***,we determine whether the mid-domain effect explains peak flowering time(i.e.,when most species of communities are flowering) across *** used phenological data of 16,267 herbaceous and woody species from the provincial Flora in China and species distribution data from the Chinese Vascular Plant Distribution Database to determine relationships between the observed number of species flowering and the number of species flowering as predicted by the mid-domain effect model,as well as between three climatic variables(mean minimum monthly temperature,mean monthly precipitation,and mean monthly sunshine duration).We found that the mid-domain effect explained a significant proportion of the temporal variation in flowering diversity across all species in ***,the mid-domain effect explained a greater proportion of variance in flowering diversity at higher latitudes than at lower *** patterns of flowering diversity for both herbaceous and woody species were related to both the mid-domain effect and environmental *** findings indicate that including geometric constraints in conjunction with abiotic and biotic predictors will improve predictions of flowering diversity patterns.

关键词： Flowering diversity Functional biogeography Latitudinal gradient Macroecology Macrophenology Null model

Control of GaN inverted pyramids growth on c-plane patterned sapphire substrates

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Journal of Semiconductors 2024年第6期45卷 92-96页

作者： Luming Yu Xun Wang Zhibiao Hao Yi Luo Changzheng Sun Bing Xiong yanjun Han Jian Wang Hongtao Li Lin Gan lai Wang Beijing National Research Center for Information Science and Technology Department of Electronic EngineeringTsinghua UniversityBei-jing 100084China Center for Flexible Electronics Technology Tsinghua UniversityBeijing 100084China

Growth of gallium nitride(GaN)inverted pyramids on c-plane sapphire substrates is benefit for fabricating novel devices as it forms the semipolar *** this work,GaN inverted pyramids are directly grown on c-plane patterned sapphire substrates(PSS)by metal organic vapor phase epitaxy(MOVPE).The influences of growth conditions on the surface morphol-ogy are experimentally studied and explained by Wulff *** competition of growth rate among{0001},{1011},and{1122}facets results in the various surface morphologies of GaN.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 can expand the area of{}facets in GaN inverted *** the other hand,GaN inverted pyramids with almost pure{}facets are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendicular to the substrate primary flat.

关键词： inverted pyramids GaN MOVPE crystal growth competition model

Studies on the nucleation of MBE grown Ⅲ-nitride nanowires on Si

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Chinese Physics B 2017年第1期26卷 344-347页

作者： Yanxiong E Zhibiao Hao Jiadong Yu Chao Wu lai Wang Bing Xiong Jian Wang yanjun Han Changzheng Sun Yi Luo Tsinghua National Laboratory for Information Science and Technology Department of Electronic Engineering Tsinghua University Beijing 100084 China

GaN and AlN nanowires（NWs） have attracted great interests for the fabrication of novel nano-sized devices. In this paper, the nucleation processes of GaN and AlN NWs grown on Si substrates by molecular beam epitaxy（MBE）are investigated. It is found that GaN NWs nucleated on in-situ formed Si3N4 fully release the stress upon the interface between GaN NW and amorphous Si3N4 layer, while AlN NWs nucleated by aluminization process gradually release the stress during growth. Depending on the strain status as well as the migration ability of Ⅲ group adatoms, the different growth kinetics of GaN and AlN NWs result in different NW morphologies, i.e., GaN NWs with uniform radii and AlN NWs with tapered bases.

关键词： GaN nanowires AlN nanowires strain nucleation

Gallium nitride blue laser diodes with pulsed current operation exceeding 15 W in optical output power

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Journal of Semiconductors 2024年第11期45卷 13-17页

作者： Shuiqing Li Qiangqiang Guo Heqing Deng Zhibai Zhong Jinjian Zheng LiXun Yang Jiangyong Zhang Changzheng Sun Zhibiao Hao Bing Xiong yanjun Han Jian Wang Hongtao Li Lin Gan lai Wang Yi Luo Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Anhui GaN Semiconductor Co. Ltd.Luan 237000China

Since Shuji Nakamura first demonstrated the nitride laser in 1996[1],the domain of semiconductor laser technology has undergone a period of remarkable growth[2,3].Al In Ga N-based diode lasers(LDs)have proven their exceptional capabilities across a spectrum of pivotal applications,including high-density data storage,laser displays,laser lighting,and quantum technology[4].

关键词： laser diodes exceeding