Improving accuracy of automatic optical inspection with machine learning

Electronic devices require the printed circuit board(PCB)to support the whole structure,but the assembly of PCBs suffers from welding problem of the electronic components such as surface mounted devices(SMDs)resistors.The automated optical inspection(AOI)machine,widely used in industrial production,can take the image of PCBs and examine the welding issue.However,the AOI machine could commit false negative errors and dedicated technicians have to be employed to pick out those misjudged PCBs.This paper proposes a machine learning based method to improve the accuracy of AOI.In particular,we propose an adjacent pixel RGB value based method to pre-process the image from the AOI machine and build a customized deep learning model to classify the image.We present a practical scheme including two machine learning procedures to mitigate AOI errors.We conduct experiments with the real dataset from a production line for three months,the experimental results show that our method can reduce the rate of misjudgment from 0.3%–0.5%to 0.02%–0.03%,which is meaningful for thousands of PCBs each containing thousands of electronic components in practice.     

Metal modified (Ni,Ce, Ta) Ti/SnO2–Sb2O5–RuO2 electrodes for enhanced electrochemical degradation of Orange G

Journal of Applied Electrochemistry - Ni, Ce, and Ta modified Ti/SnO2–Sb2O5–RuO2 anodes were first prepared by thermal decomposition strategy and applied for Orange G degradation to...     

影响LNG槽车运输储罐压力的因素分析

应用动态模拟软件,建立LNG槽车满载和空载运输系统动态模型,研究LNG槽车运输过程中储罐内操作压力、操作温度和液位的动态变化趋势。分析表明:LNG槽车满载长距离运输储罐压力上升较小,不易造成储罐超压泄放,安全性较高;空载运输较满载运输储罐升压速率更快;LNG储罐空载液位5%可实现LNG槽车储罐处于冷却状态。     

基于硫化铋低温碱性熔炼的熔体物化性质分析

基于硫化铋精矿低温碱性熔炼技术,采用半球点法、旋转柱体法、阿基米德法和拉筒法,测定Bi2S3-NaOH体系的熔化温度、高温密度以及熔体的粘度和表面张力,研究不同NaOH含量和温度对Bi_2S_3-NaOH体系物化性质的影响,结果表明,随着温度的升高,Bi_2S_3-NaOH体系熔化过程分为缓慢收缩,快速收缩和流动阶段,熔化温度随着NaOH含量的增加先减小,达到最低共熔温度后逐渐增大;Bi_2S_3-NaOH熔体的高温密度、表面张力、粘度在NaOH含量一定条件下都随着温度的升高增加而减小,温度一定条件下随着氢氧化钠含量的增加而减小。研究结果可为硫化铋精矿低温清洁冶金技术的优化提供基础数据参考。     

甲烷在钯基催化剂上脱氢的分子模拟

为探明甲烷在钯基二聚体催化剂上脱氢反应过程的微观机理,对甲烷燃烧催化剂的设计与使用提供指导。在M06L/6-311++G(d,p)+SDD//M06L/6-311G(d,p)+LANL2DZ基组水平上,采用密度泛函理论(DFT)对甲烷在钯基二聚体催化剂(Pd_2、PdPt和PdNi)上的脱氢过程进行了研究。对比了甲烷在催化剂Pd_2、PdPt和PdNi上反应的能垒(E_b)、活化能(E_a)及反应速率常数(k),结果表明:CH_2→CH是甲烷在二聚体Pd_2反应的速率控制步骤(RDS),而CH_3→CH_2是催化剂PdPt和PdNi反应的RDS;钯基二聚体催化剂对甲烷脱氢的催化活性顺序为PdPtPd_2PdNi;抗积炭性能顺序为PdNiPd_2PdPt。PdPt适用于要求催化效率较高的项目,而抗积炭性能较好的PdNi催化剂可用于大型工业催化。     

煤油气共生矿井底板油型气赋存特征及防治

为了提高煤油气共生矿井油型气灾害治理的科学性，以黄陵二矿为例，采用现场测试、钻探取芯、跟踪观测、地质分析等多种方法，研究了采掘工作面煤层底板油型气分布特征、涌出规律和运移机理，并初步探讨了底板油型气体灾害防治措施。结果表明:底板油型气涌出点多位于底板砂岩储层上倾尖灭端和砂岩透镜体附近，呈现不连续区带状分布特征，涌出的油型气主要来自富县组砂岩层，涌出的动力主要为地层流体压力差，底板油型气通过地层中存在大量的断裂和裂缝、微裂缝系统进入采掘空间，采掘扰动是底板油型气异常涌出的工程诱导因素。建议加强油型气综合探查技术、油型气灾害预测预报技术、油型气综合抽采技术和智能化矿井建设等方面的研究。     

深层长水平段页岩气井趾端压裂滑套的研制

为打破国外公司的技术垄断、解决国内深层长水平段页岩气井第一段储层改造面临的技术难题,在明确应用环境及施工要求的基础上,开展了结构设计、室内试验与评价、配套固井工艺研究,研制出了一种能够满足高温、高压固井及大排量压裂施工要求的趾端压裂滑套,并在四川盆地长宁—威远国家级页岩气示范区内的长宁H7-5井开展了现场试验。结果表明:(1)自主研发的趾端压裂滑套通过井口打压的方式打开,形成第一段压裂或泵送通道,可替代连续油管第一段射孔作业;(2)趾端压裂滑套采用内表面特殊涂层设计、内滑套上行开启结构以及压裂喷砂孔暂堵设计,可提高滑套在固井环境中的适应能力、降低固井水泥对滑套正常开启的影响;(3)趾端压裂滑套采用破裂盘破裂开启滑套的方式,可提高滑套的开启精度,保证在高温、高压条件下工具能够精确开启。结论认为,所研制的趾端压裂滑套现场工艺操作简单,工具性能稳定、可靠,开启精度高,各项指标均达到了页岩气水平井固井、压裂设计和施工的要求,提高了施工作业的效率,降低了作业的风险和成本,在深层长水平段页岩气井第一段储层改造中具有较好的推广应用前景,对于深层页岩气藏实现效益开发具有重要的现实意义。     

A comparative assessment of predicting CH4 adsorption on different activated carbons using generalized regression neural network (GRNN), and adaptive network-based fuzzy inference system (ANFIS)

The aim of this work is to predict the adsorption of methane on various activated carbon using to intelligent models including Generalized Regression Neural Network (GRNN), and adaptive network-based fuzzy inference system (ANFIS). Methane is the major component of natural gas, coal bed gas, and some exhaust gases of petrochemical or chemical units. Therefore, a fundamental study on the adsorption was encouraged by engineering concerns. In this regards, the precise prediction of CH₄ adsorption is of great interest and importance. The model is developed using a comprehensive database obtained from the literature. The outcomes of the model were compared with the experimental data. The values of the statistical parameters R², RMSE, and AARD% reveal that the ANFIS model is more accurate. Results showed that the developed model accurately predicts CH₄ adsorption on activated carbons with an overall R² and AARD% values of 0.921% and 0.657%, respectively.     

干热处理对不溶性大豆纤维乳化特性的影响

采用碱处理(AK)、烘烤—碱处理(HA)、碱处理—烘烤(AH)、碱处理—双螺杆挤压(AT)处理脱脂豆渣制备不溶性大豆纤维(ISF),以自制ISF制备O/W型乳浊液,研究干热处理对ISF乳化特性的影响。结果表明:ISF乳浊液ζ-电位依次为:AH-ISFAK-ISFAT-ISFHA-ISF,储能模量(G’)依次为:AT-ISFAH-ISFHAISFAK-ISF;4种乳浊液均呈现剪切稀化特性,干热处理ISF乳浊液tanδ1;乳浊液贮藏期间,AK-ISF的粒径(Δ_(AK-ISF)=1.916)和表观黏度(Δ_(AK-ISF)=3.898)增幅均最大,而干热处理则改善了ISF乳浊液的贮藏稳定性,以AT-ISF最好。表明干热处理显著改变了ISF乳浊液的表面电荷分布,乳浊液形成了以弹性为主的类凝胶网络结构,且静电相互作用和类凝胶网络结构是干热处理ISF乳浊液稳定的主要因素。