光学玻璃磨削亚表面损伤预测模型及DOE实验设计

为了掌握光学玻璃材料杯型砂轮研磨与表面粗糙度(SR)和亚表面损伤(SSD)机理,本文建立BK7光学玻璃杯型砂轮研磨表面粗糙度的预测模型,通过改变磨削参数来研究对表面粗糙度的影响。设计DOE试验,研究影响SR与SSD的显著性特征因子,并分析了各因子的交互作用。实验结果表明预测模型的可靠性,得到表面粗糙度的预测模型数据与实验数据的平均误差为5.47%。采用角抛光法,通过电子显微镜观测表面裂纹,并测量裂纹的深度。最后,基于Li的模型,建立基于磨削工艺参数的亚表面损伤的新预测模型。实验结果表明:实验和预测模型结果具有很好的一致性,模型数据与实验数据的平均误差为6.19%,并且新预测模型结果要优于Li的模型。

Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

基于DoE实验设计的硝酸铈溶液雾化特性研究

为满足喷雾热分解法制备氧化铈颗粒需求,使用两相流空气辅助雾化喷嘴,对不同浓度的硝酸铈溶液雾化特性进行了实验研究,并使用响应曲面法对硝酸铈溶液喷雾的雾化颗粒度SMD实验数据进行了定量分析,得到了雾化颗粒度SMD与溶液物理性质及雾化环境参数之间的定量关系。本实验中溶液质量浓度为0.334~0.462、溶液体积流量为0.05 m^(3)/h和0.12 m^(3)/h、雾化空气压力为0.2~0.5 MPa。根据对获得的定量关系式分析可知,对硝酸铈溶液雾化颗粒度SMD影响最显著的因素是溶液浓度,其次是雾化空气压力,溶液体积流量对雾化颗粒度SMD的影响较小;雾化颗粒度均随雾化空气压力的升高而减小,雾化空气压力对粘性较小溶液的影响更加显著。

Study on the effect and mechanism of Swertia mussotii Franch. in the treatment of primary biliary cholangitis based on bioinformatics and in vitro experiments

Background:Primary biliary cholangitis(PBC)is a chronic biliary autoimmune liver disease characterized by intrahepatic cholestasis.Swertia mussotii Franch.(SMF)is a Tibetan medicine with hepatoprotective and anti-inflammatory activities.In this study,the therapeutic effect and potential mechanisms of SMF on PBC were investigated by bioinformatics analysis and in vitro experimental validation,with the aim of promoting the progress of SMF and PBC research.Methods:We first explored the therapeutic effects and key targets of SMF on PBC using a network pharmacology approach,further screened the core targets using the GSE79850 dataset,and finally validated the results using molecular docking techniques and in vitro experiments.Results:By bioinformatics analysis,we identified core targets of SMF for PBC treatment(STAT3,JAK2,TNF-α,and IL-1β)and important signaling pathways:JAK-STAT,TNF,and PI3K-AKT.The molecular docking results showed that the significant components of SMF had good binding properties to the core targets.In vitro experiments showed that SMF extracts improved the extent of epithelial-mesenchymal transition in human intrahepatic biliary epithelial cells and had a significant reversal effect on epithelial-mesenchymal transition process markers and potential targets in PBC.Conclusion:SMF may exert its therapeutic effects on PBC by acting on important targets such as STAT3,JAK2,TNF-α,IL-1β,Vimentin,and E-cadherin and the pathways in which they are involved.

基于DOE方法的6061-T6铝合金焊接工艺参数优化研究

车体焊接是确保轨道交通车辆安全性与可靠性的关键环节,而焊接工艺参数的选择与控制则是决定焊接质量的重要因素。传统的焊接工艺参数获取方法依赖于大量的试验,导致试验周期长、成本高昂。为了高效、低成本地研究最佳焊接工艺参数,文章基于IGM公司的六轴自动化焊接机械手设备,以6061-T6铝合金为母材,采用DOE(试验设计)中的部分因子试验设计方法进行参数优化。通过合理的试验设计与结果分析,确定最佳焊接工艺参数组合为:送丝速度5.4 m/min,弧长修正3%,焊接速度53 cm/min,干伸长18 mm,脉冲频率2.5 Hz,有效降低了研究成本,缩短了试验周期。

Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft

In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs.

基于遗传算法优化的风洞试验MDOE方法

为提高风洞试验效率,现代试验设计(MDOE)方法正越来越频繁地用于各类飞行器风洞试验。然而,基于MDOE方法的风洞试验尽管理论上减少了试验点数量,有效缩短了风洞吹风时间,但也带来了试验数据精度下降的问题。为此发展了一种基于D-最优设计准则和二元三次多项式响应面模型的MDOE方法,同时引入遗传算法进一步提高响应面模型的拟合精度。结果表明,所开发的MDOE风洞试验方法仅需单变量(OFAT)方法30%左右的试验点数,吹风时间较OFAT方法大约缩短了60%;与最初拟合的多项式响应面模型相比,遗传算法优化后的响应面拟合精度提高了5%左右,内插得到的数据误差更小。

基于DOE的卷烟工业燃气锅炉节能优化分析

燃气锅炉是卷烟工业中常用的动力能源设备,为卷烟生产过程提供饱和蒸汽.在锅炉运行中需要消耗大量能源,如何降低锅炉的能源消耗是卷烟厂节能减排的关键.气汽比是衡量锅炉运行效能的重要指标,因此,针对锅炉气汽比的现状,通过综合分析和现场论证,确定了锅炉汽气比的主要影响因素,采用实验设计法(DOE)对锅炉运行参数进行优化,并对其效果进行了验证.结果表明,采取相应措施后,气汽比同比减少7.7%,其稳定性也得到了提升.

利用DOE和紧密堆积理论优化UHPC设计

使用DOE设计理论,根据所选原材料的性能和产品工艺要求先设定基础参数和优化目标,再基于颗粒紧密堆积理论(MAA)得到标准预混料的配合比;然后利用全因子试验筛选重要因子并确定极值范围后进行响应面模型分析;最后输出得到符合使用要求的超高性能混凝土(UHPC)配合比。验证试验结果表明:优化配合比后,所配制的UHPC流动度和密实度预测值均在误差范围内,结果较可靠。

基于DOE和信噪比的手套箱外盖注塑工艺参数优化

对汽车手套箱外盖的结构进行整体分析,为满足其复杂结构的要求并解决实际生产中出现的质量缺陷,结合Moldex3D软件,优化了浇注位置,设计了传统水路冷却+隔水板冷却的混合冷却方案。以塑件翘曲变形量为质量目标,采用DOE和信噪比均值分析方法优化注塑工艺参数,最佳工艺参数组合为充填时间2.11s、塑料温度260℃、模具温度30℃、保压时间10 s、保压压力147 MPa、冷却时间15.89 s,其中,对翘曲变形量影响最大的是模具温度。优化后,缩痕指数从0.071%降低至0.041%,降低了42.25%,体积收缩率从11.351%降低至9.005%,降低了20.67%,翘曲变形量从4.446 mm降低至1.521 mm,降低了65.79%,表面质量更加均匀,保压效果更佳,优化效果明显。经过注塑工艺参数优化和实际试生产检验后,产品性能稳定,满足注塑生产要求。

基于DOE方法的装载机械工装液压夹具优化设计

装载机械工装需要特定标准化的加工制造设备,针对其生产过程中的定位和夹紧需求,设计一种采用液压驱动的多向功能的夹具装备,通过对装载机械工装液压夹具的结构力学分析,采用DOE设计方法构建斜置铰杆增力机构式液压夹具,构建了装载机械工装液压夹具性能试验环境,通过设置不同的试验工况参数对液压夹具进行测试验证,实验结果表明,DOE设计方法所设计的装载机械工装液压夹具具有较强的稳定性和可靠性。

基于DOE的加工汽车碳纤维材料的新型钻头设计与优化

针对加工汽车碳纤维材料的钻头寿命短、加工质量差的问题,设计了一种新型钻头。通过DOE(design of experiment)试验方法,给出了钻头齿数、前角和后角等3个参数的全因子试验方案。利用MINITAB软件对试验数据进行回归分析,并利用响应优化获得最优设计参数。结果表明:齿数和后角对钻孔个数及钻头寿命影响不显著,前角对钻头寿命有显著影响,后角与前角的交互作用对钻头寿命也有显著影响。齿数、前角和后角对第一孔钻孔时间及钻孔速度有显著影响,齿数与后角的交互作用以及前角与后角的交互作用对钻孔速度有显著影响。通过试验测试验证优化后的最佳设计参数是有效合理的。

基于CFD流体模型的摆线机油泵田口DOE设计分析

机油泵作为润滑系统的关键部件,不仅对发动机正常工作有重要影响,也是整机辐射噪声中的典型噪声源。本文使用Pumplinx对某款摆线转子机油建立了CFD模型,并对仿真模型进行了试验校核,确保该流体模型能准确反映机油泵实际工作能力。对机油泵有无卸载槽、间隙组合、含气量、机油粘度和转速等因素进行混合田口DOE设计,制定了18种方案组合,根据流体仿真结果考察分析了各因素水平对高压腔的气体体积分数、出口压力、出口流量和机油泵端面压差的主效应贡献,发现卸载槽设计可降低高压腔压力波动幅值和端面压差,从而可实现降低压力波动引起的机油泵噪声;机油泵的端隙和外转子一腔体间隙存在最优值组合,推荐端隙不大于5丝、外转子一腔体径向间隙不大于10丝,为机油泵的功能设计提供有力的理论指导。其中机油参数(包括含气量、机油黏度等)和工作转速对机油泵的性能有明显影响,分析结果对机油泵的运行边界控制具有一定指导意义。

Design of Experiments (DOE)—A Valuable Multi-Purpose Methodology

The DOE methodology is an effective tool for upgrading the level of measurement and assessment. In any design, planning or control problem the designer is faced with many alternatives. He/she is challenged to develop design approaches that can meet both quality and cost criteria. The way experiments are designed greatly affects the effective use of the experimental resources and the easiness with which the measured results can be analyzed. This paper does not present new evidence based on designed experiments. Its objective is solely to show how useful application of multifactor experiments is in a variety of circumstances and decision making scenarios. The paper reviews three published examples where this method was used in different contexts: quality control, flexible manufacturing systems (FMS) and logistics systems. The physical experiment has been carried out to improve the quality of a special type of batteries. The simulation experiment has been carried out to investigate the impact of several flexibility factors in a flexible manufacturing system. The numerical value of a complex analytical expression representing a customer oriented logistics performance measure has been calculated for different values of its parameters, i.e. the given numerical values of the investigated factors. It enabled a methodical examination of all factor effects and especially their interactions, thus shedding light on complex aspects of the logistics decision problem. In these examples, cases from different contexts were presented, enabling to view design of experiments as a powerful ingredient for improving decision making in a variety of circumstances.

Exploration of playa surface crusts in Qehan Lake, China through field investigation and wind tunnel experiments

Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial distribution of playa surface crusts is important to recognize the manifestation of salt dust storms.The objective of this study was to explore the playa surface crust types as well as their spatial distribution and evolution of Qehan Lake in Inner Mongolia Autonomous Region,China to understand the salt dust release potential of different types of playa surface crusts.Various crust characteristics were investigated by field sampling in Qehan Lake,and playa surface crusts were further divided into five types:vegetated areas,salt crusts,clay flats,curly crusts,and margins.It should be noted that curly crusts were distributed in clay flats and covered only a small area in Qehan Lake.The spatial distribution characteristics of playa surface crust types were obtained by supervised classification of remote sensing images,and the salt dust release potential of crusts was explored by the wind tunnel experiments.The field investigation of Qehan Lake revealed that playa surface crust types had a circum-lake band distribution from the inside to the outside of this lake,which were successively vegetated areas,clay flats,salt crusts,and margins.The spatial distribution patterns of playa surface crust types were mainly controlled by the hydrodynamics of the playa,soil texture,and groundwater.There was a significant negative correlation between crust thickness and electrical conductivity.The results of the wind tunnel experiments showed that the initial threshold of friction wind velocity for the salt dust release was higher in clay flats(0.7–0.8 m/s)than in salt crusts(0.5–0.6 m/s).Moreover,the particle leap impact processes occurring under natural conditions may reduce this threshold value.Salinity was the main factor controlling the difference in the initial threshold of friction wind velocity for the salt dust release of clay flats and salt crusts.This study provides a scientific reference for understanding how salt dust is released from a lakebed,which may be used for ecological restoration of dry salt lakes.

基于DOE的铁氧体隔离器衰减片点锡焊接工艺优化

铁氧体隔离器作为一种大量应用于5G通讯基站的通讯元器件,其可靠性关系到基站整机运行的持续性与稳定性,而隔离器的衰减片存在的焊接空洞问题可能导致隔离器在再流焊过程中发生失效,严重时导致基站电路板烧毁,因此管控及降低衰减片焊接空洞率十分重要。首先对铁氧体隔离器的衰减片焊接空洞产生的机理进行分析,并通过实验设计(Design of Experiment,DOE)对点锡过程中可能导致焊接空洞问题的因素进行了析因分析及点锡工艺的优化。实验结果表明,通过控制点锡轨迹及点锡速度,能显著减少焊接空洞,并明显提升该焊接过程的制程能力,大幅提升了分布参数隔离器的可靠度,降低了隔离器经历再流焊后失效的风险。

基于DOE的电池包底部球击的仿真分析研究

基于电池包底部球击工况的仿真,以预浸料模压成型(PCM)底板替代钢底板,以实现电池包底板的减重。通过RADIOSS软件建立电池包底部球击仿真模型,分析球击完成后底板为钢板和PCM板时,应力应变分布和模组变形情况。钢板方案下,模组变形量为2.03 mm,PCM方案下,模组变形量为2.62 mm,PCM板方案较差,不满足要求,进行试验设计(DOE),对PCM板材料参数进行因子筛选,得到最优方案。选取部分底板进行试验,并与模拟结果进行对比分析,验证复材仿真建模的准确性。将优化后的PCM底板代入整包模型再次仿真,模组变形量为2.27 mm,结果满足模组变形量小于2.5 mm的要求。通过研究,PCM底板可以替代钢板,在满足要求的前提下,质量减轻40%。此研究可以为电池包的底板设计和轻量化提供指导。

基于DOE的锆合金包壳管冷轧质量分析及改善

为了提高锆合金包壳管的冷轧质量,通过统计过程控制技术和工序能力分析研究了锆合金包壳管冷轧后的壁厚偏差问题,并基于试验设计(design of experiment, DOE)技术对皮格尔冷轧工艺进行了优化。包壳管冷轧质量分析和工艺优化试验的结果表明,轧制前管材的壁厚偏差和送进量对轧制后的管材壁厚偏差有显著影响;当轧制前管材壁厚偏差<0.3 mm、壁厚变形量为65%、送进量为1.0 mm/次时,轧制后的管材壁厚偏差最小;通过轧制工艺优化后,反映壁厚偏差离散性的极差平均值由0.036减小到0.018,极差波动也明显减小,轧制质量显著提高;当轧制管材壁厚变形量一定时,对轧制前壁厚偏差较大的管材,采用小送进量轧制,可减小轧制后管材的壁厚偏差,达到提高锆合金包壳管材质量的目的。

基于DOE的后排座椅鞭打优化

2021版C-NCAP中新增后排座椅的动态鞭打要求。后排座椅骨架不同于前排座椅,无法完全借鉴前排的开发经验,考虑到影响鞭打的因素众多,文章基于DOE试验方法,研究了头后间隙、头枕高度、头枕杆直径、头枕杆厚度、头枕EPP和靠背MTM等6个影响因子与鞭打得分各指标的函数关系,并给出了最优解:当头后间隙缩小至25 mm,头枕高度增高至低于头部10 mm,头枕杆直径增大至16 mm,头枕杆厚度增加至1.4 mm,增加头枕EPP,移动儿童座椅上固定点至坐垫上使得靠背MTM增大至60 mm时,鞭打得分由0.21分提升至1.48分。采用最优解方案的座椅实物鞭打得分为1.56分,与DOE最优解的得分水平相当,满足得分目标。

基于DOE的甘蔗渣微波液化优化研究

目的:对甘蔗渣微波加热液化进行优化分析,以确定最佳的液化条件。方法:以甘蔗渣为原料,以聚乙二醇400、甘油为液化试剂,以浓硫酸为催化剂,构建以液化温度、时间和催化剂用量为因子的三因素三水平全因子实验设计(DOE),进行多因子显著性分析。结果:三因子对液化率的影响顺序为液化温度>催化剂浓度>液化时间,且前两者为显著因子。通过验证,当液化温度为160℃,催化剂用量为3%,液化时间为20min时,液化率达到最高为98.56%。结论:DOE分析是植物纤维液化条件探索和优化的有效方法。