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Surface roughness classification using light scattering matrix and deep learning

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Science China(Technological Sciences) 2024年第2期67卷 520-535页

作者： SUN Hao TAN Wei RUAN YiXiao bai Long xu JianFeng State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Wuhan Digital Design and Manufacturing Innovation Center Co. LtdWuhan 430074China

High-quality optical components have been widely used in various applications;thus,extremely high beam quality is ***,surface roughness is a key indicator of the surface *** this study,the angular distribution of light scattering field intensity was obtained for surfaces having different roughness profiles based on the finite difference time domain(FDTD)method,and the results were compared with those obtained using the generalized Harvey-Shack(GHS)*** was shown that the FDTD approach can be used for an accurate simulation of the scattered field of a rough surface,and the superposition of results obtained from many surfaces that have the same roughness level was in good agreement with the result given by the analytic GHS model.A light scattering matrix(LSM)method was proposed based on the FDTD simulation results that could obtain rich surface roughness *** classification effect of LSM was compared with that of the single-incidence scattering distribution(SISD)based on a ResNet-50 deep learning *** classification accuracy of the model trained with the LSM dataset was obtained as 95.74%,which was 23.40%higher than that trained using the SISD ***,the effects of different noise types and filtering methods on the classification performance were analyzed,and the LSM was also shown to improve the robustness and generalizability of the trained surface roughness ***,the proposed LSM method has important implications for improving the data acquisition scheme of current light scattering measurement systems,and it also has the potential to be used for detection and characterization of surface defects of optical components.

关键词： surface roughness FDTD simulation GHS theory deep learning light scattering matrix

基于下潜超深风险的潜艇耐压船体结构设计方法

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上海交通大学学报 2016年第1期50卷 110-114,122页

作者：白旭江苏科技大学船舶与海洋工程学院江苏镇江212003

针对潜艇耐压船体结构在下潜过程中存在的下潜超深风险问题,探讨了基于风险的结构设计方法;提出了基于风险的结构设计思想.对下潜超深风险进行了定义,并依据个人、社会、经济以及环境对风险的态度,制定了基于风险的结构设计准则.采用极... 详细信息

针对潜艇耐压船体结构在下潜过程中存在的下潜超深风险问题,探讨了基于风险的结构设计方法;提出了基于风险的结构设计思想.对下潜超深风险进行了定义,并依据个人、社会、经济以及环境对风险的态度,制定了基于风险的结构设计准则.采用极值I型分布分析计算了不同下潜超深的风险发生概率,结合基于风险的结构设计准则,建立了耐压船体的可靠性优化设计模型并进行计算,绘制了随着设计载荷增加耐压船体结构重量变化曲线,依据成本-效益准则对耐压船体结构的设计方案进行了决策.

关键词：下潜超深结构设计方法耐压船体可靠性成本-效益

The effect of selected alloying element additions on properties of Mg-based alloy as bioimplants： A literature review

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Frontiers of Materials Science 2013年第3期7卷 227-236页

作者： Li-Nan ZHANG Zeng-Tao HOU Xin YE Zhao-Bin xu xue-Ling bai Peng SHANG Center for Translational Medicine Research and Development Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen 518055 China

This review investigates the current application limitations of Mg and Mg alloys. The key issues hindering the application of biodegradable Mg alloys as implants are their fast degradation rate and biological consideration. We have discussed the effect of some selected alloying element additions on the properties of the Mg-based alloy, especially the nutrient elements in human （Zn, Mn, Ca, St）. Different grain sizes, phase constituents and distributions consequently influence the mechanical properties of the Mg alloys. Solution strengthening and precipitation strengthening are enhanced by the addition of alloying elements, generally improving the mechanical properties. Besides, the hot working process can also improve the mechanical properties. Combination of different processing steps is suggested to be adopted in the fabrication of Mg-based alloys. Corrosion properties of these *** alloys have been measured in vitro and in vivo. The degradation mechanism is also discussed in terms of corrosion types, rates, by- products and response of the surrounding tissues. Moreover, the clinical response and requirements of degradable implants are presented, especially for the nutrient elements （Ca, Mn, Zn, Sr）. This review provides information related to different Mg alloying elements and presents the promising candidates for an ideal implant.

关键词： magnesium alloy alloying element corrosion biodegradation

Heat distribution model under hydrogen-rich low-carbon conditions in blast furnace

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Journal of Iron and Steel Research International 2024年第3期31卷 584-594页

作者： Gang Wang Jun xu Kun He Zhong-ping Zou Hao bai School of Metallurgy and Ecological Engineering University of Science and Technology BeijingBeijing 100083China CISDI Low-Carbon Blast Furnace Research Office MCC Low-Carbon Technology Research InstituteChongqing 401122China

Low carbon development of blast furnaces is one of the key technological directions in the current development of *** to the differences in the physical and chemical properties of hydrogen and carbon,hydrogen-rich media entering a blast furnace will change the heat distribution,thus affecting the stability of ***,a heat distribution model was proposed to study the temperature distribution in a blast furnace,simultaneously considering gas-solid heat exchange,slag and iron melting,and chemical *** model was used to analyze the temperature distribution of a 2300 m^(3) blast furnace and was verified via comparison with actual production ***,the effects of the injection rate of hydrogen-rich media,H2 concentration,and oxygen enrichment rate of the blast on the temperature distribution were *** indicated that the increase in the injection rate of the hydrogen-rich media decreased the amount of direct reduction and led to an increase in the furnace ***,an increase in the oxygen enrichment rate led to a decrease in the furnace temperature,but could reduce the solid fuel ratio,while the change in H2 concentration had less effect on the temperature *** combination of hydrogen-rich media injection and the increase in the oxygen enrichment rate would help to adjust the temperature distribution to the same level as the conventional blast furnace conditions.

关键词： Heat distribution Blast furnace Low-carbon condition Hydrogen enrichment Calculation model

Femoral epithelioid hemangioendothelioma detected with magnetic resonance imaging and positron emission tomography/computed tomography:A case report

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World Journal of Clinical Cases 2021年第6期9卷 1353-1358页

作者： Hong-Guang Zhao Ke-Wei Zhang Sen Hou Yu-Yin Dai Song-bai xu Department of Nuclear Medicine The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Thoracic Surgery The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Neurosurgery The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

BACKGROUND Epithelioid hemangioendothelioma(EHE)is an uncommon low-grade aggressive vascular *** can occur in almost all locations,but is rarely encountered in *** SUMMARY We report a 23-year-old man who presented with left hip pain with no obvious cause.X-ray revealed bone destruction in the left femoral neck with sclerosis at the edges of the *** resonance imaging(MRI)showed bone destruction in the medullary cavity of the left femoral head and neck.18Fdeoxyglucose-positron emission tomography/computed tomography(PET/CT)imaging showed bone destruction in the left ischium,acetabulum,and left femoral head neck,accompanied by increased radioactive uptake;the maximum standard uptake value was *** examination revealed spindleshaped mesenchymal tissue hyperplasia with scattered epithelioid *** patient underwent left femoral head replacement *** signs of recurrence were observed as of the 18-mo *** The definitive diagnosis of femoral EHE can be established aided by the MRI and PET/CT findings.

关键词： Bone radiography Hemangioendothelioma Epithelioid Vascular tumor Pathology Case report

Determination of ethanol content in ethanol-gasoline based on derivative absorption spectrometry and information fusion

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Optoelectronics Letters 2018年第6期14卷 442-446页

作者： ZHOU Kun-peng bai xu-fang BI Wei-hong School of Physics and Electronic Information Inner Mongolia University for Nationalities The Key Laboratory for Special Fiber and Fiber Sensor of Hebei Province School of Information Science and Engineering Yanshan University

The ethanol content in ethanol-gasoline is respectively detected by the first-order derivative UV/vis absorption spectrum, the first-order derivative near infrared(NIR) absorption spectrum and the information fusion method. The backward interval partial least squares(BiPLS) algorithm is used as the feature extraction method, which is established by the partial least squares(PLS) regression model. Based on the information fusion theory, the low level data fusion(LLDF) and mid-level data fusion(MLDF) models are established by the first-order derivative UV/vis and NIR spectra. The analytical results are compared with the related textual references. Thereby, the single-spectral model based on the first-order derivative NIR absorption spectrum has the optimal results, where R_p^2 =0.999 1 and RMSEP=0.324 5, while the LLDF after vector normalization(LLDF-VN2) is the optimal multi-spectral fusion model, where R_p^2 =0.998 3 and RMSEP=0.498 2. The proposed method can be used to detect the ethanol content in ethanol-gasoline rapidly and provides a better choice for the component detection in mixed oils.

关键词： derivative absorption spectrometry information fusion ethanol-gasoline

干摩擦工况下氮化硅基底制备CrAlN涂层工艺参数优化

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工具技术 2024年第10期58卷 20-26页

作者：陆鹤吴玉厚刘子金王贺闫广宇白旭郭建成郑桐翔沈阳建筑大学机械工程学院现代建筑工程装备与技术国际合作联合实验室

为了延长氮化硅材料在干摩擦工况下的使用寿命，采用射频磁控溅射技术在氮化硅基底制备CrAlN涂层。利用正交试验法，以CrAlN涂层的干摩擦磨损率为试验指标，探究溅射时间、基底温度、氮气流量和溅射功率对涂层干摩擦工况下摩擦学性能的... 详细信息

为了延长氮化硅材料在干摩擦工况下的使用寿命，采用射频磁控溅射技术在氮化硅基底制备CrAlN涂层。利用正交试验法，以CrAlN涂层的干摩擦磨损率为试验指标，探究溅射时间、基底温度、氮气流量和溅射功率对涂层干摩擦工况下摩擦学性能的影响。利用超景深显微镜、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、摩擦磨损试验机、轮廓粗糙度测试仪和能谱仪(EDS)分析CrAlN涂层的微观形貌、晶体结构、化学成分和表面摩擦学性能，得到优化的工艺参数。分析结果表明，基底温度和溅射功率对CrAlN涂层磨损率的影响程度较大，溅射时间和氮气流量对CrAlN涂层磨损率的影响程度较小。在溅射时间为240min、基底温度为350℃、氮气流量为40sccm和溅射功率为120W的工艺参数下，CrAlN涂层的干摩擦摩擦学性能较好。研究结果可为氮化硅基底在干摩擦工况下应用CrAlN涂层的工艺参数设定提供数据支撑。

关键词：氮化硅陶瓷干摩擦 CrAlN涂层正交试验工艺优化

n-Type Semiconductive Polymers Based on Pyrene-1,5,6,10-Tetracarboxyl Diimide

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高分子科学:英文版 2023年第10期41卷 1584-1590页

作者： xu-Dong bai Zi-Di Yu Yao Li Tian-Yu Zhang Di Zhang Jie-Yu Wang Jian Pei Da-Hui Zhao Beijing National Laboratory for Molecular Sciences Centre of Soft Matter Science and Engineering and Key Lab of Polymer Chemistry&Physics of Ministry of EducationCollege of ChemistryPeking UniversityBeijing100871China

Donor-acceptor(D-A)conjugated polymers comprising electron-deficient aromatic dicarboximide units represent an important type of organic semiconductors,especially for electron transporting ***-1,5,6,10-tetracarboxyl diimide(PyDI),a new PAH dicarboximide molecule recently reported by us,provides a fine balance between the electron-stabilizing ability andπ-stacking tendency,as compared to the naphthalenediimide(NDI)and perylenediimide(PDI)*** this study,using thienylene-vinylene-thienylene(TVT)and biselenophene(BS)as the electron donating comonomer,along with PyDI as the acceptor moiety,we develop two new D-A type conjugated polymers,which exhibit impressive electron-transporting ***,in the solution-processed OFET devices,electron mobility of 0.18 and 0.20 cm^(2)·V^(−1)·s^(−1) are achieved with these polymers,*** findings further prove the optimal potential of PyDI for application as an electron-acceptor building block in the development of polymeric n-type semiconductors among all various high-performance functional D-A polymers.

关键词： Pyrenedimide Conjugated polymers Donor-acceptor Organic electronics

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欠驱商船的自主靠泊轨迹规划研究

江苏科技大学学报（自然科学版） 2024年第1期38卷 1-6,35页

作者：李永正陈怡白旭张海华杨立许凯玮张茜赵师纬江苏科技大学船舶与海洋工程学院镇江212100 中国船舶科学研究中心上海分部上海200011

针对大型商船在自主靠泊时的轨迹规划任务,分别考虑远码头轨迹规划和码头末端镇定靠泊两部分.基于大型船舶自身特点及限制等多约束分析的分阶段路径规划方法,完成面向大型商船自主靠泊的轨迹规划任务.考虑大型商船自身体型较大,低速运... 详细信息

针对大型商船在自主靠泊时的轨迹规划任务,分别考虑远码头轨迹规划和码头末端镇定靠泊两部分.基于大型船舶自身特点及限制等多约束分析的分阶段路径规划方法,完成面向大型商船自主靠泊的轨迹规划任务.考虑大型商船自身体型较大,低速运动时船舶的舵效和实船操纵性能差等难题,提出大型船舶自身限制等多约束分析的人工势场法,改进传统人工势场法中存在引力过大、目标不可达的问题.同时考虑镇定阶段船舶自身及泊位信息对船舶艏向和速度的约束,绘制舵角的输出变化曲线,并进行航迹规划,为商船选择合适的航线进行靠泊提供了理论依据.

关键词：自主靠泊欠驱人工势场法商船