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Chinese Journal of Aeronautics 2024年第6期37卷 410-424页

作者： Qiannan TAO Yanrong WANG Dasheng WEI shun yang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Nanchang 330096China

Predicting the thickness of Thermally Grown Oxide(TGO)and the residual stresses induced by TGO growth in the Thermal Barrier Coatings(TBCs)is significant work in analyzing the failure of *** practical applications,the operating temperature,oxygen partial pressure,aluminium content in TBCs,and porosity of the topcoat affect the oxidation ***,a novel oxidation rate model is proposed to describe the effect of such *** parameters in the proposed model were fitted with isothermal degradation test data from prior ***,a method for calculating the residual stress in a disk-shaped specimen was developed based on the oxidized growth strain model and the oxidized ***,a variable-temperature oxidation experiment was performed to validate the new oxidation *** average error between the predicted and experimental thicknesses is approximately 10%,and the average error between the residual stresses is 30%.Under the variable-temperature condition,the error between the predicted thickness and the average experimental thickness is 3.9%.

关键词： Thermal barrier coatings Oxidation Gas turbine Residual stresses Sintering

A discussion of fatigue properties of notched specimens subjected to prestressing treatment machined from FGH4097

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Chinese Journal of Aeronautics 2024年第4期37卷 508-523页

作者： Rongxi SHI Dasheng WEI Le HAN shun yang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute Beihang UniversityNanchang 330096China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Experimental and numerical investigations were performed to reveal the effect of prestress on the fatigue properties of FGH4097 so as to quantitatively evaluate the overspeed benefit of the disc of aeroengine. A corresponding experiment was performed to examine the effect of prestress on the fatigue life of FGH97. A complete model describing the fatigue properties of the prestressed notch specimen was proposed. After the modification of mean stress, stress gradient and prestressing treatment, the model is finally verified by fatigue test of presstressed notch specimens machined from FGH4097 with satisfactory accuracy and good engineering applicability. The new model highlights that for the variable fatigue loads, the introduction of appropriate prestress is expected to benefit to the notch specimens and certainly to the disc of aeroengine regards of their fatigue properties. Both the calculation method of fatigue life parameters and the prestress correction model are proved to have good prediction accuracy.

关键词： Turbine blisk Overspeed test Prestress Fatigue life prediction FGH4097

Acyclic Edge Coloring of 1-planar Graphs without 4-cycles

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 35-44页

作者： Wei-fan Wang Yi-qiao Wang Wan-shun yang Department of Mathematics Zhejiang Normal UniversityJinhua321004China School of Management Beijing University of Chinese MedicineBeijing100029China School of Mathematics and Information Science Weifang UniversityWeifang261061China

An acyclic edge coloring of a graph G is a proper edge coloring such that there are no bichromatic cycles in *** acyclic chromatic index χ'α(G) of G is the smallest k such that G has an acyclic edge coloring using k *** was conjectured that every simple graph G with maximum degree Δ has χ'_α(G) ≤Δ+2.A1-planar graph is a graph that can be drawn in the plane so that each edge is crossed by at most one other *** this paper,we show that every 1-planar graph G without 4-cycles has χ'_α(G)≤Δ+22.

关键词： 1-planar graph acyclic edge coloring acyclic chromatic index

Application of Gaussian Beam Summation Migration in Reflected In-seam Wave Imaging

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 276-284页

作者： HAN Jianguang LÜQingtian ZHANG Zhiheng yang shun WANG Shuo Chinese Academy of Geological Sciences Beijing 100037China Shandong Taishan Resources Exploration Co. Ltd.Jinan 250104China

The geological conditions for coal mining in China are complex,with various structural issues such as faults and collapsed columns seriously compromising the safety of coal mine ***-seam wave exploration is an effective technique for acquiring detailed information on geological structures in coal seam working ***,the existing reflected in-seam wave imaging technique can no longer meet the exploration precision requirements,making it imperative to develop a new reflected in-seam wave imaging *** study applies the Gaussian beam summation(GBS)migration method to imaging coal seams'reflected in-seam wave ***,with regard to the characteristics of the reflected in-seam wave data,methods such as wavefield removal and enveloped superposition are employed for the corresponding wavefield separation,wave train compression and other processing of reflected in-seam ***,imaging is performed using the GBS migration *** feasibility and effectiveness of the proposed method for reflected in-seam wave imaging are validated by conducting GBS migration tests on 3D coal-seam fault models with different dip angles and *** applying the method to reflected in-seam wave data for an actual coal seam working face,accurate imaging of a fault structure is obtained,thereby validating its practicality.

关键词： reflected in-seam wave Gaussian beam summation migration numerical tests fault

Diabetes and susceptibility to COVID-19:Risk factors and preventive and therapeutic strategies

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World Journal of Diabetes 2024年第8期15卷 1663-1671页

作者： Jing-Wen Liu Xiao Huang Ming-Ke Wang Ji-shun yang School of Pharmacy Bengbu Medical UniversityBengbu 233000Anhui ProvinceChina Naval Medical Center Naval Medical UniversityShanghai 200052China

Coronavirus disease 2019(COVID-19)is a highly infectious disease caused by a novel human coronavirus called severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Diabetes is a well-known risk factor for infectious diseases with high prevalence and increased ***,we elucidated the possible factors for the increased vulnerability of diabetic patients to SARS-CoV-2 infection and the more severe COVID-19 *** worsened prognosis of patients with both COVID-19 and diabetes may be attributable to host receptor angiotensinconverting enzyme 2-assisted viral ***,insulin resistance is often associated with impaired mucosal and skin barrier integrity,resulting in microbiota dysbiosis,which increases susceptibility to viral *** may also be associated with higher levels of pro-inflammatory cytokines resulting from an impaired immune system in diabetics,inducing a cytokine storm and excessive *** review describes diabetes mellitus and its complications,explains the risk factors,such as disease characteristics and patient lifestyle,which may contribute to the high susceptibility of diabetic patients to COVID-19,and discusses preventive and therapeutic strategies for COVID-19-positive diabetic patients.

关键词： Diabetes mellitus SARS-CoV-2 COVID-19 Susceptibility Prevention Treatment

Clinical application value of long non-coding RNAs signatures of genomic instability in predicting prognosis of hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2024年第8期16卷 2386-2392页

作者： Xiao-Wen Xing Xiao Huang Wei-Peng Li Ming-Ke Wang Ji-shun yang Department of Disease Control and Prevention Naval Medical CenterNaval Medical UniversityShanghai 200052China Medical Care Center Naval Medical UniversityShanghai 200052China

Hepatocellular carcinoma(HCC)presents challenges due to its high recurrence and metastasis rates and poor *** current clinical diagnostic and prognostic indicators exist,their accuracy remains imperfect due to their biol-ogical ***,there is a quest to identify improved biomarkers for HCC diagnosis and *** combining long non-coding RNA(lncRNA)expression and somatic mutations,Duan et al identified five representative lncRNAs from 88 lncRNAs related to genomic instability(GI),forming a GI-derived lncRNA signature(LncSig).This signature outperforms previously re-ported LncSig and TP53 mutations in predicting HCC *** this editorial,we comprehensively evaluate the clinical application value of such prognostic evaluation model based on sequencing technology in terms of cost,time,and ***,we provide an overview of various prognostic models for HCC,aiding in a comprehensive understanding of research progress in pro-gnostic evaluation methods.

关键词： Hepatocellular carcinoma Prognosis Prognostic model Biomarkers Genomic instability long non-coding RNA Clinical application value

Urgent call for attention to diabetes-associated hospital infections

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World Journal of Diabetes 2024年第8期15卷 1683-1691页

作者： Xue-Lu Yu Li-Yun Zhou Xiao Huang Xin-Yue Li Qing-Qing Pan Ming-Ke Wang Ji-shun yang Department of Disease Control and Prevention Naval Medical Center of PLANaval Medical UniversityShanghai 200052China Medical Care Center Naval Medical Center of PLANaval Medical UniversityShanghai 200052China

In this editorial,we discuss the recent article by Zhao et al published in the World Journal of Diabetes,which highlights the importance of recognizing the risk indicators associated with diabetes mellitus(DM).Given the severe implications of healthcare-associated infections(HAIs)in hospitalized individuals-such as heightened mortality rates,prolonged hospitalizations,and increased costs-we focus on elucidating the connection between DM and nosocomial *** patients are susceptible to pathogenic bacterial invasion and subsequent infection,with some already harboring co-infections upon ***,DM is an important risk factor for nosocomial urinary tract infections and surgical site infections,which may indirectly affect the occurrence of nosocomial bloodstream infections,especially in patients with DM with poor glycemic *** evidence regarding the impact of DM on healthcare-associated pneumonias remains inconclusive,attention to this potential association is *** patients with DM should prioritize meticulous blood glucose management,adherence to standard operating procedures,hand hygiene practices,environmental disinfection,and rational use of drugs during *** studies are imperative to explore the main risk factors of HAIs in patients with DM,enabling the development of preventative measures and mitigating the occurrence of HAIs in these patients.

关键词： Diabetes mellitus Healthcare-associated infections Nosocomial urinary tract infections Surgical site infections Nosocomial bloodstream infections

美国大学“第一年教育”:功能定位、实施路径与运行保障

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高等教育研究 2024年第3期45卷 99-109页

作者：杨顺饶从满东北师范大学国际与比较教育研究院吉林长春130024

大学新生入学后的“第一年教育”是美国大学在高等教育进入普及化阶段后,为应对高中与大学教育衔接面临的新问题、提高本科教育质量而采取的重要举措。美国大学“第一年教育”主要通过开设新生研讨课、组建学习共同体、实施同伴引领计... 详细信息

大学新生入学后的“第一年教育”是美国大学在高等教育进入普及化阶段后,为应对高中与大学教育衔接面临的新问题、提高本科教育质量而采取的重要举措。美国大学“第一年教育”主要通过开设新生研讨课、组建学习共同体、实施同伴引领计划、提供新生入学指导和学业指导等方式,来帮助新生适应学习和生活方式的转变进而促进其可持续发展。美国大学“第一年教育”的有效运行取决于校内多个部门之间的协作。其相关举措对提升我国大学新生教育质量具有重要的参考价值。

关键词：第一年教育高中与大学教育衔接美国大学

Combined prevention and treatment measures are essential to control nosocomial infections during the COVID-19 pandemic

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World Journal of Virology 2024年第2期13卷 11-18页

作者： Jing-Wen Liu Yue-Yue Li Ming-Ke Wang Ji-shun yang Medical Care Center Naval Medical Center of PLANaval Medical UniversityShanghai 200052China School of Pharmacy Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina Department of Disease Control and Prevention Naval Medical Center of PLANaval Medical UniversityShanghai 200052China

Severe acute respiratory syndrome coronavirus-2 is a highly contagious positive-sense,single-stranded RNA virus that has rapidly spread *** of December 17,2023,772838745 confirmed cases including 6988679 deaths have been reported *** virus primarily spreads through droplets,airborne transmission,and direct *** harbor a substantial number of confirmed coronavirus disease 2019(COVID-19)patients and asymptomatic carriers,accompanied by high population density and a larger susceptible *** factors serve as potential triggers for nosocomial infections,posing a threat during the COVID-19 *** infections occur to varying degrees across different countries worldwide,emphasizing the urgent need for a practical approach to prevent and control the intra-hospital spread of *** study primarily concentrated on a novel strategy combining preventive measures with treatment for combating COVID-19 nosocomial *** suggests preventive methods,such as vaccination,disinfection,and training of heathcare personnel to curb viral ***,it explored therapeutic strategies targeting cellular inflammatory factors and certain new medications for COVID-19 *** methods hold promise in rapidly and effectively preventing and controlling nosocomial infections during the COVID-19 pandemic and provide a reliable reference for adopting preventive measures in the future pandemic.

关键词： COVID-19 SARS-CoV-2 Nosocomial infection Prevention Treatment

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结合扩散模型图像编辑的图文检索后门攻击

计算机科学与探索 2024年第4期18卷 1068-1082页

作者：杨舜陆恒杨江南大学人工智能与计算机学院江苏省模式识别与计算智能工程实验室江苏无锡214122

深度神经网络在模型训练阶段易受到后门攻击,在训练图文检索模型时,如有攻击者恶意地将带有后门触发器的图文对注入训练数据集,训练后的模型将被嵌入后门。在模型推断阶段,输入良性样本将得到较为准确的检索结果,而输入带触发器的恶意... 详细信息

深度神经网络在模型训练阶段易受到后门攻击,在训练图文检索模型时,如有攻击者恶意地将带有后门触发器的图文对注入训练数据集,训练后的模型将被嵌入后门。在模型推断阶段,输入良性样本将得到较为准确的检索结果,而输入带触发器的恶意样本会激活模型隐藏后门,将模型推断结果恶意更改为攻击者设定的结果。现有图文检索后门攻击研究都是基于在图像上直接叠加触发器的方法,存在攻击成功率不高和带毒样本图片带有明显的异常特征、视觉隐匿性低的缺点。提出了结合扩散模型的图文检索模型后门攻击方法(Diffusion-MUBA),根据样本图文对中文本关键词与感兴趣区域(ROI)的对应关系,设计触发器文本提示扩散模型,编辑样本图片中的ROI区域,生成视觉隐匿性高且图片平滑自然的带毒训练样本,并通过训练模型微调,在图文检索模型中建立错误的细粒度单词到区域对齐,把隐藏后门嵌入到检索模型中。设计了扩散模型图像编辑的攻击策略,建立了双向图文检索后门攻击模型,在图-文检索和文-图检索的后门攻击实验中均取得很好的效果,相比其他后门攻击方法提高了攻击成功率,而且避免了在带毒样本中引入特定特征的触发器图案、水印、扰动、局部扭曲形变等。在此基础上,提出了一种基于目标检测和文本匹配的后门攻击防御方法,希望对图文检索后门攻击的可行性、隐蔽性和实现的研究能够抛砖引玉,推动多模态后门攻防领域的发展。

关键词：后门攻击图文检索扩散模型感兴趣区域