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非线性Benjamin-Bona-Mahony-Burgers方程的非协调有限元超收敛分析

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郑州航空工业管理学院学报 2024年第2期42卷 102-107页

作者：廖歆赵国营郑州航空工业管理学院数学学院河南郑州450046 32738部队河南郑州450046

文章研究了二维非线性Benjamin-Bona-Mahony-Burgers(BBMB)方程的非协调有限元方法。利用非协调EQ^(rot)_(1)元相容误差比插值误差高一阶的特殊性质,给出了非线性BBMB方程在半离散以及向后Euler全离散格式下的超逼近和整体超收敛结果。... 详细信息

文章研究了二维非线性Benjamin-Bona-Mahony-Burgers(BBMB)方程的非协调有限元方法。利用非协调EQ^(rot)_(1)元相容误差比插值误差高一阶的特殊性质,给出了非线性BBMB方程在半离散以及向后Euler全离散格式下的超逼近和整体超收敛结果。最后,通过数值试验验证了理论分析的正确性和方法的有效性。

关键词：非线性BBMB方程非协调EQ^(rot)_(1)元半离散格式向后Euler全离散格式超逼近和超收敛

Distinguishing Between Natural and GAN-Generated Face Images by Combining Global and Local Features

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Chinese Journal of Electronics 2022年第1期31卷 59-67页

作者： CHEN Beijing TAN Weijin WANG Yiting zhao guoying Engineering Research Center of Digital Forensics Ministry of Education Nanjing University of Information Science and Technology School of Computer Nanjing University of Information Science and Technology Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET) Nanjing University of Information Science and Technology Warwick Manufacturing Group University of Warwick Center for Machine Vision and Signal Analysis University of Oulu

With the development of face image synthesis and generation technology based on generative adversarial networks(GANs), it has become a research hotspot to determine whether a given face image is natural or generated. However, the generalization capability of the existing algorithms is still to be improved. Therefore,this paper proposes a general algorithm. To do so, firstly,the learning on important local areas, containing many face key-points, is strengthened by combining the global and local features. Secondly, metric learning based on the Arc Face loss is applied to extract common and discriminative features. Finally, the extracted features are fed into the classification module to detect GAN-generated *** experiments are conducted on two publicly available natural datasets(Celeb A and FFHQ) and seven GANgenerated datasets. Experimental results demonstrate that the proposed algorithm achieves a better generalization performance with an average detection accuracy over 0.99 than the state-of-the-art algorithms. Moreover, the proposed algorithm is robust against additional attacks, such as Gaussian blur, and Gaussian noise addition.

关键词： Generated image Global feature Local features Generative adversarial network Metric learning

Chlorogallate(Ⅲ) ionic liquids: Synthesis, acidity determination and their catalytic performances for isobutane alkylation

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Science China Chemistry 2012年第8期55卷 1542-1547页

作者： XING XueQi zhao guoying CUI JianZhong Beijing Key Laboratory of lonic Liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Department of Chemistry Tianjin UniversityTianjin 300072China

A series of triethylammonium-based chlorogallate（Ⅲ） ionic liquids with varied Lewis acidity was synthesized, characterized, and firstly applied to isobutane alkylation. The [Et3NHC1]-GaCl3 with XGaCl3 =0.65 displayed a potential catalytic activity for the alkylation. The addition of copper halide into the chlorogallate（Ⅲ） ionic liquids dramatically enhanced the alkylation reac- tion. Up to 70.1% Cs selectivity and 91.3 RON were achieved with the [Et3NHC1]-GaC13-CuC1 （XGaCl3 = 0.65, CuCI = 5% tool） under 0.5 MPa, 900 r/min, 15 min, 288 K using the industrial C4 cut （isobutane/butene = 10）. These results indicate that the chlorogallate（Ⅲ） system may be used as a promising catalyst for the C4 alkylation.

关键词： chlorogallate(Ⅲ) acidic ionic liquid Lewis acid alkylation isobutane

Properties and Structures of Bi_2O_3-B_2O_3-TeO_2 Glass

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Journal of Materials Science & Technology 2013年第3期29卷 209-214页

作者： guoying zhao Ying Tian Huiyan Fan Junjie Zhang Lili Hu Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences Graduate School of Chinese Academy of Sciences SCHOTT Glass Technologies(Suzhou) Co. Ltd

Glass formation range of Bi2O3-B2O3-TeO2 system has been investigated （B2O3 ≤ 40 mol%）. Four glasses with compositions xBi2O3-B2O3-（70-x）TeO2 （x = 40, 50, 60 and 70 tool%） have been prepared by using melt quenching technique. The effect of Bi2O3 content on thermal stability, optical properties and structures of these four Bi2O3-B2O3-TeO2 glasses is systematically investigated by inductive coupled plasma emission spectrometer （ICP）, differential scanning calorimetry （DSC）, Raman spectra and X-ray photoelectron spectroscopy （XPS）. It is found that the density, refractive index and optical basicity increase with increasing Bi2O3. The Raman spectra and XPS spectra show that the glass network is mainly constituted by the [BiO6] octahedron, [TeO4] trigonal bipyramidal, [TeO3] trigonal pyramid, [BO3] trigonal pyramid and [B04] tetrahedron structural units. With increasing Bi2O3, the coordination number around B atom changes from 3 to 4 and [TeO4] units are converted to [TeO3] units. Bi5＋ ions may exist in Bi2O3-B2O3-TeO2 （BBT） system and their amount grows with increasing Bi2O3 content.

关键词： Bismuth glass Glass forming region Raman and X-ray photoelectron spectroscopy (XPS) spectra

晚期肺癌炎症指数对老年ACS患者预后的预测价值

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浙江临床医学 2024年第5期26卷 665-668页

作者：赵国滢唐文斌黄进宇浙江中医药大学第四临床医学院 310000 杭州市第一人民医院 310000

目的探讨晚期肺癌炎症指数对老年急性冠状动脉综合征患者经皮冠状动脉介入术后全因死亡率的预测价值。方法选取2018年1月至2018年12月杭州市第一人民医院接受PCI治疗的老年ACS患者366例,根据入院时ALI最佳截断值分为两组,低ALI组120例,... 详细信息

目的探讨晚期肺癌炎症指数对老年急性冠状动脉综合征患者经皮冠状动脉介入术后全因死亡率的预测价值。方法选取2018年1月至2018年12月杭州市第一人民医院接受PCI治疗的老年ACS患者366例,根据入院时ALI最佳截断值分为两组,低ALI组120例,高ALI组246例。术后连续随访36个月。采用ROC曲线、多因素COX回归分析和Kaplan-Meier曲线评估ALI对患者全因死亡率的预测价值。结果ALI预测老年ACS患者发生全因死亡的ROC曲线下面积为0.737(95%CI:0.677~0.798,P<0.001)。多因素COX回归分析中,年龄(HR=0.959,95%CI:0.922~0.998,P=0.038)、ALI(HR=0.950,95%CI:0.903~0.998,P=0.042)和GRACE(HR=1.031,95%CI:1.023~1.039,P<0.001)是老年ACS患者全因死亡的独立预测因素。Kaplan-Meier曲线显示,低ALI组老年ACS患者的中位生存期短于ALI组,差异有统计学意义(P<0.001)。结论ALI与老年ACS患者的全因死亡存在相关性,老年ACS患者入院时的低ALI水平是PCI术后全因死亡的独立危险因素。ALI可能有助于评估老年ACS患者预后。

关键词：急性冠状动脉综合征晚期肺癌炎症指数经皮冠状动脉介入术老年

A novel ionic liquids-based scrubbing process for efficient CO_(2) capture

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Science China Chemistry 2010年第7期53卷 1549-1553页

作者： ZHANG SuoJiang ZHANG XiangPing zhao YanSong zhao guoying YAO XiaoQian YAO HongWei State Key Laboratory of Multiphase Complex System Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of SciencesBeijing 100049China

A novel alkanolamine-based ionic liquid,N-methyl-diethanolammonium tetrafluoroborate ([MDEA][BF4]),was synthesized in our *** ionic liquid-based composite solution consisting of N-methyl-diethanolamine (MDEA),[MDEA][BF4],piperazine (PZ) and H2O was investigated for CO_(2) *** optimal performance for CO_(2) capture was found at 45°C,1.50 MPa,probably due to a synergistic action of the reaction and the *** apparent corrosion was found on stainless and carbon steel with the above composite *** finding is very significant to the promotion of its engineering application.

关键词： carbon dioxide capture ionic liquids corrosion molecular simulation

Saliency-Based Segmentation of Optic Disc in Retinal Images

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Chinese Journal of Electronics 2019年第1期28卷 71-75页

作者： ZOU Beiji LIU Qing YUE Kejuan CHEN Zailiang CHEN Jie zhao guoying School of Information Science and Engineering Central South University Hunan First Normal University School of Information Science and Engineering Center for Machine Vision and Signal Analysis University of Oulu

Accurate segmentation of Optic disc(OD)is significant for the automation of retinal analysis and retinal diseases screening. This paper proposes a novel optic disc segmentation method based on the saliency. It includes two stages: optic disc location and saliency-based segmentation. In the location stage, the OD is detected using a matched template and the density of the *** the segmentation stage, we treat the OD as the salient object and formulate it as a saliency detection *** measure the saliency of a region, the boundary prior and the connectivity prior are exploited. Geodesic distance to the window boundary is computed to measure the cost the region spends to reach the window *** a threshold and ellipse fitting, we obtain the *** results on two public databases for OD segmentation show that the proposed method achieves thestate-of-the-art performance.

关键词： Retinal fundus Optic disc segmentation Boundary prior Region connection Saliency measure

12-Tungstophosphoric acid niched in Zr-based metal-organic framework:a stable and efficient catalyst for Friedel-Crafts acylation

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Science China Chemistry 2018年第4期61卷 402-411页

作者： Latif Ullah guoying zhao Zichen Xu Hongyan He Muhammad Usman Suojiang Zhang Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process EngineeringState Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Center of Excellence in Nanotechnology King Fahd University of Petroleum and MineralsDhahran 3126Saudi Arabia

Heteropoly acids(HPA) are well known for their versatile solid acid catalysis in diverse chemical reactions, however they suffer from low surface area(<10 m^2/g) and leaching into the reactions media, which reduce their prospects as industrial ***, a novel hybrid material HPW@Zr-BTC,composed of 12-tungstophoric acid(HPW) and Zr^(Ⅳ)-benzene tri-carboxylate(Zr-BTC) metal-organic framework(MOF), was prepared via one-pot solvothermal method. Excellent HPW loading up to 32.3 wt% was achieved, and HPW@Zr-BTC composite proved to be highly stable, besides the crystalline morphology of Zr-BTC was intact. The catalytic activity of the hybrid composite was explored via Friedel-Crafts acylation of anisole with benzoyl *** 28.2 wt% HPW@Zr-BTC showed excellent catalytic performance, with 99.4% anisole conversion and 97.6% yield(pmethoxybenzophenone) under solvent free conditions. Excellent retention of catalytic activity was achieved after at least five consecutive runs due to non-observable HPW leaching. The promising activity and stability of the catalyst forecasted its potential industrial applications.

关键词： dodeca-tungstophosphoric acid Zr-BTC metal-organic frameworks one-pot solvothermal synthesis heterogeneouscatalysis anisole acylation high temperature XRD

Polarization manipulation of bright-dark vector bisolitons

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Chinese Physics B 2021年第3期30卷 306-313页

作者： Yan Zhou Xiaoyan Lin Meisong Liao guoying zhao Yongzheng Fang School of Science Shanghai Institute of TechnologyShanghai 201418China Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Materials Science and Engineering Shanghai Institute of TechnologyShanghai 201418China

We simulate the polarization manipulation of bright-dark vector bisolitons at 1-µm wavelength *** changing the pulse parameters,different kinds of pulse shapes and optical spectra are generated in output orthogonal polarization *** the input vector bisoliton is polarization-locked with 1064 nm central wavelength,“1+1”fundamental dark-dark and“2+1”pseudo-high-order bright-dark group-velocity-locked vector solitons can be achieved through changing the projection *** the input vector bisoliton is group-velocity-locked with 1063 nm and 1065 nm central wavelengths,“2+1”and“2+2”pseudo-high-order bright-dark group-velocity-locked vector solitons,bright-dark group-velocity-locked vector solitons with chirp-like temporal oscillations are *** simulation results can provide beneficial conduct for polarization manipulation of vector multi-solitons,and have promising applications in quantum information register,optical communications,nanophotonics,and all-optical switching.

关键词： polarization manipulation vector bisoliton polarization-locking group-velocity-locking linear birefringence