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Investigation of an electrode-driven hydrogen plasma method for in situ cleaning of tin-based contamination

Plasma Science and Technology 2024年第8期26卷 73-83页

作者：彭怡超叶宗标王思蜀蒲国刘显洋苑聪聪廖加术韦建军余新刚芶富均 Key Laboratory of Radiation Physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan UniversityChengdu 610064People’s Republic of China Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610064People’s Republic of China Institute of High Performance Scientific Computation Xihua UniversityChengdu 610039People’s Republic of China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049People’s Republic of China

To prolong the service life of optics,the feasibility of in situ cleaning of the multilayer mirror(MLM)of tin and its oxidized contamination was investigated using hydrogen plasma at different power *** tin-based contamination consisting of micro-and macroparticles was deposited on silicon via physical vapor deposition(PVD).The electrodedriven hydrogen plasma at different power levels was systematically diagnosed using a Langmuir probe and a retarding field ion energy analyzer(RFEA).Moreover,the magnitude of the self-biasing voltage was measured at different power levels,and the peak ion energy was corrected for the difference between the RFEA measurements and the self-biasing voltage(E_(RFEA)-eV_(self)).XPS analysis of O 1s and Sn 3d peaks demonstrated the chemical reduction process after 1 W *** of surface and cross-section morphology revealed that holes emerged on the upper part of the macroparticles while its bottom remained *** and folds appeared on the upper part of the microparticles,confirming the top-down cleaning mode with hydrogen *** study provides an in situ electrode-driven hydrogen plasma etching process for tin-based contamination and will provide meaningful guidance for understanding the chemical mechanism of reduction and etching.

关键词： tin-based contamination hydrogen plasma in situ cleaning ion energy

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基于强化学习的B型主动脉夹层定位方法

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生物医学工程学杂志 2024年第5期41卷 878-885页

作者：曾安林先扬赵靖亮潘丹杨宝瑶刘鑫广东工业大学计算机学院广州510006 广东技术师范大学电子与信息学院广州510665

主动脉夹层分割中存在主动脉夹层与周围器官和血管的对比度低、夹层形态差异大以及背景噪声大等问题。针对以上问题,本文提出一种基于强化学习的B型主动脉夹层定位方法,借助两阶段分割模型,使用深度强化学习执行第一阶段的主动脉定位任... 详细信息

主动脉夹层分割中存在主动脉夹层与周围器官和血管的对比度低、夹层形态差异大以及背景噪声大等问题。针对以上问题,本文提出一种基于强化学习的B型主动脉夹层定位方法,借助两阶段分割模型,使用深度强化学习执行第一阶段的主动脉定位任务,保证定位目标的完整性;在第二阶段,使用第一阶段的粗分割结果作为输入,得到精细的分割结果。为了提高一阶段分割结果的召回率(Recall),使定位结果更完整地包含分割目标,本文设计了基于Recall变化方向的强化学习奖励函数;同时,将定位窗口与视野窗口分离,减少分割目标缺失的情况。本文选取Unet、TransUnet、SwinUnet以及MT-Unet作为基准分割模型,通过实验验证,本文的两阶段分割流程结果中多数指标均优于基准结果,其中Dice指标分别提高1.34%、0.89%、2..66%和7.37%。综上,将本文的B型夹层定位方法加入分割流程,最终的分割精度较基准模型结果有所提升,对于分割效果较差的模型提升效果更显著。

关键词：主动脉夹层两阶段分割强化学习奖励函数

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一类时滞泛函差分系统的多个正周期解的存在性

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吉首大学学报（自然科学版） 2024年第4期45卷 1-4,14页

作者：朱先阳铜仁学院大数据学院贵州铜仁554300

利用Banach空间中的锥不动点定理,分析了一类具有反馈控制项的时滞泛函差分系统,给出了这类系统存在多个正周期解的充分条件.

关键词：时滞差分系统正周期解反馈控制不动点定理

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基于利率贴现模型的随机占优比较

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中国科学院大学学报（中英文） 2024年第4期41卷 433-441页

作者：庄玮玮杜先杨邱国新中国科学技术大学管理学院合肥230026 安徽新华学院商学院合肥230088

建立单笔投资的利率贴现模型按照一阶随机占优序、二阶随机占优序以及风险偏好型随机占优序递减的充分条件。若组合系数按超优序递减,投资组合情况下的利率贴现模型按照二阶随机占优序、风险偏好型随机占优序递减的充分条件也做了分析。

关键词：随机占优超优利率贴现模型投资组合

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Empirical Analysis of Agricultural Production Efficiency in Shaanxi Province

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Asian Agricultural Research 2012年第3期4卷 15-18页

作者： WAN Sheng-xin School of Politics and Management,xianyang normal {{2.,xianyang 712000,china

This article analyses the agricultural production efficiency of all cities and areas in Shaanxi Province in the period 2.06-2.09 using data envelopment analysis method,and compares the agricultural production efficiency between all cities and *** results show that the agricultural production efficiency and scale efficiency of agriculture of Shaanxi Province are high on the whole,but the efficiency of agricultural technology is very low,agricultural development still relies on factor inputs,and the driving role of technological progress is not *** the following countermeasures are put forward to promote agricultural productivity in Shaanxi Province:improve the construction of agricultural infrastructure,and increase agricultural input;accelerate the project of extending agricultural technology into households,and promote the conversion and use rate of agricultural scientific and technological achievements;establish and improve industrial system of agriculture,and speed up the building of various agricultural cooperative economic organizations.

关键词： Data envelopment analysis Agricultural production

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The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2.1. School of Physics and Electronic Engineering, Yantai normal {2., Yantai 2.402.,{2. 2. Department of Physics, Shandong normal {2., Jinan 2.0014,{2. School of Physics and Electronic Engineering Yantai Normal University Yantai China Department of Physics Shandong Normal University Jinan China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

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一种自学习的新型单幅图像超分辨率高质量重建算法

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微电子学与计算机 2024年第5期41卷 1-10页

作者：欧阳甜江先阳武汉大学物理科学与技术学院湖北武汉430072 武汉大学物理国家级实验教学示范中心湖北武汉430072

经典的基于稀疏表示和字典学习的超分辨率算法在图像重建质量和计算复杂度上都具备较好的表现。然而,基于外部样本训练得到的字典和待重建图像缺少相关性,会伴随算法鲁棒性较差的问题。为克服这一缺点,提出了一种基于自学习的新型单幅... 详细信息

经典的基于稀疏表示和字典学习的超分辨率算法在图像重建质量和计算复杂度上都具备较好的表现。然而,基于外部样本训练得到的字典和待重建图像缺少相关性,会伴随算法鲁棒性较差的问题。为克服这一缺点,提出了一种基于自学习的新型单幅图像超分辨率高质量重建算法。该算法无需引入外部训练图像,即完全通过待重建图像自身构建的样本进行字典学习和图像重建;这一机制增强了训练字典与待重建图像的相关性。具体而言,在字典训练阶段,针对输入的待重建图像,基于二维经验模态分解进行高频修复预处理,以增强样本源的高频特征;随后构建训练样本集,使用K-奇异值分解算法获得自学习主字典和自学习残差字典,构成双字典。在图像重建阶段,将双字典结构与自学习相结合,先通过主字典实现主高频恢复,再进一步通过残差字典恢复图像的残差高频信息。实验结果表明,所提算法在重建图像的主观视觉效果以及专业质量评价指标上,相对于传统插值算法及经典的字典学习算法具有显著优势。

关键词：超分辨率重建稀疏表示字典学习自学习

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Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china Chemistry 2006年第4期49卷 296-307页

作者： LI Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. Department of Chemistry, Southwest-{2. normal {2., Chongqing 400715, china 2. Department of Chemistry, Sichuan {2., Chengdu 610064, china Department of Chemistry Southwest-China Normal University Chongqing China Department of Chemistry Sichuan University Chengdu China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

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Timing and geochemical characters of the Sanchazi magmatic arc in Mianlüe tectonic zone,South Qinling

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Science china Earth Sciences 2004年第4期47卷 317-328页

作者： LI Shuguang1, HOU Zhenhui1, YANG Yongcheng2. SUN Weidong1,1), ZHANG Guowei3, & LI Qiuli1 1. School of Earth and Space Sciences,university of Science and Technology of{2. ,Hefei 2.002.,{2. 2. Regional Geological Survey Team of Shaanxi Province,xianyang 712000,{2. 3. Department of Geology, Northwest university,Xi抋n 710069,{2. School of Earth and Space Sciences University of Science and Technology of China Hefei China Regional Geological Survey Team of Shaanxi Province Xianyang China Max-Planck-Institut f. Chemie Mainz Germany Department of Geology Northwest University Xi’an China

The Sanchazi mafic-ultramafic complex in Mianlüe tectonic zone,South Qinling can be subdivided into two blocks,*** paleo-magmatic arc and Zhuangkegou paleo-oceanic crust fragment (ophiolite).The Sanchazi paleo-magmatic arc is mainly composed of ande-site,basaltic and basalt-andesitic gabbro(or diorite),andesitic dyke,plagiogranite and minor ul-tramafric rocks,which have typical geochemical features of island arc volcanic rocks,such as high field strength element(***,Ti)depletions and lower Cr,Ni *** Light rare earth element (LREE) and K enrichments of these rocks and zircon xenocrystals of 900 Ma from plagiogranite suggest that this magmatic arc was developed on the South active continental margin of the South Qinling *** U-Pb age of (300±61) Ma for zircons from plagiogranite in-dicates that the Mianlüe paleo-oceanic crust was probably subducted underneath the South Qinling micro-continent in *** is consistent with the formation time (309Ma) of the Huwan eclogite originating form oceanic subduction in Dabie Mountains,suggesting that the Mianlüe paleo-ocean probably extended eastward to the Dabie Mountains in *** high-Mg adakitic rocks in Sanchazi paleo-magmatic arc suggest thet the subducted oceanic crust was relatively young (2.Ma) and hot.

关键词： Qinling orogen, magmatic arc, U-Pb zircon age, ophiolite complex.

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Research on the Anonymity Method Based-on kanonymity for Electronic Commerce

Research on the Anonymity Method Based-on kanonymity for Ele...

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2.12.National Conference on Information Technology and Computer Science

作者： Gaizhen YI School of Information & Engineering xianyang normal university xianyang,{{2.,712000 Zhenglong XIE School of Information & Engineering xianyang normal university xianyang,{{2.,71{2.0

According to the model of K-anonymity,the attributes of information tables in Electronic Commerce have been divided into three parts:identifier,Quasi Identifier,sensitive *** conceal privacy information for consumer,the paper adopted a recode method to protect the name and cell-phone number against revealing,used the generalization algorithm to conceal the quasi identifier for *** data resource of paper derived from the Adult *** has been analyzed on the correlations among of the generalization hierarchy,the ratio of information loss and *** result provided an alternative scheme of data processing decision for data holder.

关键词： Electronic Commerce K-anonymity generalization ratio of information loss

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