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Data-driven Stochastic Programming with Distributionally Robust Constraints Under Wasserstein Distance:Asymptotic Properties

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Journal of the Operations Research Society of China 2021年第3期9卷 525-542页

作者： Yu Mei zhi-ping Chen Bing-Bing Ji Zhu-Jia xu Jia Liu Department of Computing Science School of Mathematics and StatisticsXi’an Jiaotong UniversityXi’an 710049China Center for Optimization Technique and Quantitative Finance Xi’an International Academy for Mathematics and Mathematical TechnologyXi’an 710049China

Distributionally robust optimization is a dominant paradigm for decision-making problems where the distribution of random variables is *** investigate a distributionally robust optimization problem with ambiguities in the objective function and countably infinite *** ambiguity set is defined as a Wasserstein ball centered at the empirical *** on the concentration inequality of Wasserstein distance,we establish the asymptotic convergence property of the datadriven distributionally robust optimization problem when the sample size goes to *** show that with probability 1,the optimal value and the optimal solution set of the data-driven distributionally robust problem converge to those of the stochastic optimization problem with true ***,we provide numerical evidences for the established theoretical results.

关键词： Distributionally robust optimization Wasserstein distance Ambiguity set Asymptotic analysis Empirical distribution

Plasma Niobium Surface Alloying of Pure Titanium and its Oxidation at 900 ℃

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Chinese Journal of Aeronautics 2007年第2期20卷 111-114页

作者： WANG Wen-bo ZHONG xu HE zhi-yong WANG Zhen-xia ZHANG ping-ze Research Institute of Surface Engineering Taiyuan University of Technology Taiyuan 030024 China Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A niobium-modified layer on pure titanium surface was obtained by means of double glow plasma surface alloying technique. The modified layer was uniform, continuous, compact and well adhered to the substrate. The niobium composition in the modified layer decreased gradually from the surface to the substrate. The oxidation behavior of the niobium-modified layer was investigated and com- pared with the untreated surface at 900 ~C for 100 h. Characterization of the layers was performed using X-ray diffraction and scanning electron microscope, respectively. The test results show that the oxidation behavior of pure titanium was improved by niobium alloying process. Niobium has a positive influence on the oxidation resistance.

关键词： niobium pure titanium plasma surface alloying oxidation

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屈原研究之我见

三峡大学学报（人文社会科学版） 2025年第1期47卷 13-17页

作者：徐志啸复旦大学中文系上海200433

历史上确有屈原其人,他创作的作品据《汉书·艺文志》记载共25篇,其中《离骚》是代表作,集中表现了屈原的人物形象、坎坷经历及其理想追求。屈原的初衷是当政治家、改革家,旨在振兴楚国,而不是要成为文学家和诗人。屈原的爱楚国,与今天... 详细信息

历史上确有屈原其人,他创作的作品据《汉书·艺文志》记载共25篇,其中《离骚》是代表作,集中表现了屈原的人物形象、坎坷经历及其理想追求。屈原的初衷是当政治家、改革家,旨在振兴楚国,而不是要成为文学家和诗人。屈原的爱楚国,与今天的爱国主义,不是同一概念。屈原属于堪与意大利但丁比肩的世界一流大诗人。从某种意义上可以说,楚辞姓“楚”,屈原姓“屈”。

关键词：屈原《离骚》改革家世界大诗人爱国主义

Graphene-decorated microfiber knot as a broadband resonator for ultrahigh-repetition-rate pulse fiber lasers

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Photonics Research 2018年第10期6卷 I0003-I0009页

作者： MENG Liu RUI TANG AI-ping Luo WEN-CHENG xu zhi-CHAO LUO Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices & Guangzhou Key Laboratory for Special Fiber Photonic Devices and Applications South China Normal University Guangzhou 510006 China Guangdong Provincial Engineenng Technology Research Center for Microstructured Functional Fibers and Devices South China Normal University Guangzhou 510006 China

Searching for an ultrahigh-repetition-rate pulse on the order of hundreds of gigahertz(GHz) is still a challenging task in the ultrafast laser community. Recently, high-quality silicon/silica-based resonators were exploited to generate a high-repetition-rate pulse based on the filter-driven four-wave mixing effect in fiber lasers. However,despite their great performance, the silicon/silica-based resonators still have some drawbacks, such as single waveband operation and low coupling efficiency between the fiber and resonators. To overcome these drawbacks,herein we proposed an all-fiber broadband resonator fabricated by depositing the graphene onto a microfiber knot. As a proof-of-concept experiment, the graphene-deposited broadband microfiber knot resonator(MKR)was applied to Er-and Yb-doped fiber lasers operating at two different wavebands, respectively, to efficiently generate hundreds-of-GHz-repetition-rate pulses. Such a graphene-deposited broadband MKR could open some new applications in ultrafast laser technology, broadband optical frequency comb generation, and other related fields of photonics.

关键词：重复频率脉冲激光技术发展现状通讯技术

Microstructure and antibacterial property of stainless steel implanted by Cu ions

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 328-331页

作者： xu Bo-fan NI Hong-wei XIONG ping-yuan XIONG Juan DAN zhi-gang School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China School of Medicine Science Wuhan 430081 China School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China School of Material and Metallurgy Wuhan University of Science and Technology Wuhan 430081 China

Copper ions were implanted into AISI 304 austenitic stainless steel by metal vapor vacuum are (MEVVA) with 60 - 100 keV energy and a dose range (0.2 - 5.0) × 1017 cm-2. Then Cu-implanted stainless steel was treated by a special antibacterial treatment. Antibacterial rates of Cu-implanted stainless steel, Cu-implanted stainless steel with special antibacterial treatment and un-implanted stainless steel were obtained by agar plate method. Phase composition in the implanted layer was analyzed by glancing X-ray diffraction (GXRD). Microstructure of antibacterial stainless steel was observed with transmission electron microscopy (TEM), and changes of the bacterium appearance after 24 h antibacterial action on the surface of un-implanted and Cu-implanted stainless steel with antibacterial treatment were observed with bio-TEM respectively. The results show that stainless steel obtains antibacterial property against E. coli when the Cu ions dose approaches to the saturated one. A suitable amount of Cu-rich phase uniformly disperses on the surface of Cu-implanted stainless steel that is treated by the special antibacterial treatment. The Cu-rich phase naked on the surface has a function of damage to pericellular membrane and cell wall,the pericellular membrane is thickened and the karyon degraded, and finally, bacteria die. Cu-rich phase naked on the surface endows stainless steel with best antibacterial property.

关键词： stainless steel copper ion implantation antibacterial property

Triterpene Acids from Cynoglossum amabile

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Chemical Research in Chinese Universities 2009年第3期25卷 404-406页

作者： xu Qing-jun ZHANG De-zhi DANG Li-juan LI Kun-ping College of Pharmacy Guangdong Pharmaceutical University Guangzhou 510006 P. R. China

Cynoglossum amabile Stapf et Drumm is widely distributed in southern China, which has been used as an anti-inflammatory, antihepatitis, anticystitis agent in Chinese folk medicine. However, only a few phytochemical researches have been performed . Therefore, a systematic chemical investigation of it was carried out. In this work, we further investigated the chemical constituents and ten compounds were obtained, three of which were triterpene acids.

关键词： Cynoglossum amabile Triterpene acid Amabilic acid

Application of dynamic vibration absorber for vertical vibration control of corrugated rolling mill

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Journal of Iron and Steel Research International 2023年第4期30卷 736-748页

作者： Dong-ping He Hui-dong xu Ming Wang Tao Wang Chao-ran Ren zhi-hua Wang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment Ministry of EducationTaiyuan 030024ShanxiChina

A variable mass tuned particle absorber is designed for the nonlinear vertical vibration control of the corrugated rolling mill in the composite plate rolling *** the nonlinear damping and nonlinear stiffness between the corrugated interface,a three-degree-of-freedom nonlinear vertical vibration mathematical model of corrugated rolling mill based on dynamic vibration absorber control is *** multi-scale method is used to solve the amplitude–frequency characteristic curve equation of the installed dynamic vibration absorber(DVA)*** effects of stiffness coefficient and damping coefficient on the amplitude–frequency characteristic curve are *** expressions of the dynamic developed factor of the corrugated roll are derived,and the influence laws of mass ratio,frequency ratio and damping ratio on the dynamic amplification factor are *** optimal parameters of the DVA are obtained by adaptive genetic *** control effect of the DVA on the nonlinear vertical vibration is studied by numerical *** feasibility of the designed dynamic absorber is verified through *** results show that the designed dynamic absorber can effectively suppress the vertical vibration of the corrugated roller.

关键词： Corrugated rolling mill Nonlinear vertical vibration Adaptive genetic algorithm Multiscale method Dynamic vibration absorber

Impact of SNP-SNP interactions of DNA repair gene ERCC5 and metabolic gene GSTP1 on gastric cancer/atrophic gastritis risk in a Chinese population

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World Journal of Gastroenterology 2018年第5期24卷 602-612页

作者： Liang Sang zhi Lv Li-ping Sun Qian xu Yuan Yuan Department of Ultrasound the First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Tumor Etiology and Screening Department of Cancer Institute and General Surgery the First Affiliated Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Key Laboratory of Cancer Etiology and Prevention Liaoning Provincial Education DepartmentChina Medical UniversityShenyang 110001Liaoning ProvinceChina National Clinical Research Center for Digestive Diseases Xi’an 710032Shaanxi ProvinceChina

AIM To investigate the interactions of the DNA repair gene excision repair cross complementing group 5(ERCC5) and the metabolic gene glutathione S-transferase pi 1(GSTP1) and their effects on atrophic gastritis(AG) and gastric cancer(GC) *** Seven ERCC5 single nucleotide polymorphisms(SNPs)(rs1047768, rs2094258, rs2228959, rs4150291, rs4150383, rs751402, and rs873601) and GSTP1 SNP rs1695 were detected using the Sequenom MassA RRAY platform in 450 GC patients, 634 AG cases, and 621 healthy control subjects in a Chinese *** Two pairwise combinations(ERCC5 rs2094258 and rs873601 with GSTP1 rs1695) influenced AG risk(P_(interaction) = 0.008 and 0.043, respectively), and the ERCC5 rs2094258-GSTP1 rs1695 SNP pair demonstrated an antagonistic effect, while ERCC5 rs873601-GSTP1 rs1695 showed a synergistic effect on AG risk OR = 0.51 and 1.79, respectively). No pairwise combinations were observed in relation to GC risk. There were no cumulative effects among the pairwise interactions(ERCC5 rs2094258 and rs873601 with GSTP1 rs1695) on AG susceptibility(P_(trend) > 0.05). When the modification effect of Helicobacter pylori(H. pylori) infection was evaluated, the cumulative effect of one of the aforementioned pairwise interactions(ERCC5 rs873601-GSTP1 rs1695) was associated with an increased AG risk in the case of negative H. pylori status(P_(trend)= 0.043).CONCLUSION There is a multifarious interaction between the DNA repair gene ERCC5 SNPs(rs2094258 and rs873601) and the metabolic gene GSTP1 rs1695, which may form the basis for various inter-individual susceptibilities to AG.

关键词： Excision repair cross complementing group 5 Glutathione S-transferase pi 1 Atrophic gastritis Gastric cancer Single nucleotide polymorphisms

基于多分支增强和融合注意力机制的水下图像增强算法

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陕西科技大学学报 2025年第1期43卷 193-202页

作者：姚斌韩典芝徐轩李婉陕西科技大学电子信息与人工智能学院陕西西安710021

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBFA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计... 详细信息

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBFA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计了青品色温修复模块和模糊恢复模块对水下图像进行色彩矫正和模糊恢复.然后,基于对多个分支特征的互补性考虑,采用循环合并策略将多个分支增强的特征利用自适应融合模块进行融合,逐步增强图像细节.最后,设计了融合注意力模块,用于深度挖掘图像在通道维度和像素维度的相关性矩阵,以提高增强图像的真实性.实验结果表明,与现有算法相比,提出的水下图像增强算法去模糊效果较好且颜色更真实,可以有效改善水下图像色偏和模糊的问题.

关键词：水下图像增强多分支增强融合注意力生成对抗网络