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China Ocean Engineering 2024年第4期38卷 557-571页

作者： DENG Rui HU Yu-xiao HUANG Si-chong SONG Zhi-jie wang shi-gang WU Tie-cheng School of Ocean Engineering and Technology Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China

To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different *** lift forces are obtained by numerical calculations and validated by a model test in a towing *** factors that influence the force are the interceptor height,velocity,draft,and deadrise *** relationship between each factor and the induced lift force is investigated and *** found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and *** results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally *** on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic *** proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.

关键词： high-speed mono-hull ship interceptor lift force formula lift force towing tank test computational fluid dynamics

基于BM-TransUNet的咽后壁识别分割

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计算机系统应用 2024年第7期33卷 94-102页

作者：王世刚孙静雯广西科技大学自动化学院柳州545616

图像分割经历了从基于传统的阈值分割等方法逐步发展到基于卷积神经网络的方法.传统的卷积神经网络在分割领域中表现突出,但训练速度慢、分割精度不够高等局限性也逐渐显现.为了克服这些局限性,本文在TransUNet网络的基础上进行改进,提... 详细信息

图像分割经历了从基于传统的阈值分割等方法逐步发展到基于卷积神经网络的方法.传统的卷积神经网络在分割领域中表现突出,但训练速度慢、分割精度不够高等局限性也逐渐显现.为了克服这些局限性,本文在TransUNet网络的基础上进行改进,提出了基于BM-TransUNet网络的图像分割识别方法,在TransUNet网络的在第1层之后加上深度可分离卷积模块,并在编码器下采样的卷积层后引入注意力机制模块,让算法更好地探索分割对象特征,同时在编码器与解码器之间引入多尺度特征融合模块FPN.本文基于自制的咽后壁数据集,用于图像分割训练,并将训练后的BM-TransUNet网络与多种传统分割网络的效果进行对比.实验结果表明,相比于其他传统的深度学习模型,BM-TransUNet网络的识别方法具有较高的分类准确性和泛化能力,精确度Precision和Dice系数分别达到了93.61%和90.76%,显示出较好的计算效率,能有效地应用于分割任务.

关键词： BM-TransUNet网络图像分割注意力机制模块多尺度特征融合模块咽后壁数据集

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Moderate Deviations for Parameter Estimation in the Fractional Ornstein–Uhlenbeck Processes with Periodic Mean

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1308-1324页

作者： Hui JIANG shi Min LI Wei gang wang School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China The People's Bank of China Operations Ofice of Nanjing Branch Nanjing 210016P.R.China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018P.R.China

In this paper,we study the asymptotic properties for the drift parameter estimators in the fractional Ornstein-Uhlenbeck process with periodic mean function and long range *** Cremér-type moderate deviations,as well ... 详细信息

关键词： Cramér-type moderate deviation fractional Ornstein-Uhlenbeck process parameter estimation multiple Wiener-Ito integrals

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太宽河野生蕙兰濒危机制分析与保护研究

安徽农业科学 2024年第5期52卷 112-115页

作者：赵腊梅王刚狮刘瑞霞时宝凌贾泽凡山西运城农业职业技术学院山西运城044000 山西林业职业技术学院山西太原030009 山西省中条山国有林管理局山西侯马043003

[目的]为野生蕙兰(Cymbidium faberi Rolfe)种质资源的保护与利用提供科学依据,为太宽河自然保护区管理局野生蕙兰种群繁育和恢复奠定基础。[方法]采用固定样方法,对野生蕙兰的资源进行调查,运用濒危系数分析法,以能够反映蕙兰濒危程度... 详细信息

[目的]为野生蕙兰(Cymbidium faberi Rolfe)种质资源的保护与利用提供科学依据,为太宽河自然保护区管理局野生蕙兰种群繁育和恢复奠定基础。[方法]采用固定样方法,对野生蕙兰的资源进行调查,运用濒危系数分析法,以能够反映蕙兰濒危程度的活株数、自然枯死株数、幼苗数、开花植株数、坐果植株数、动物啃咬株数、人为采挖株数作为评价指标,对野生蕙兰濒危程度进行了定量分析。[结果]各指标濒危系数表现为动物啃咬濒危系数(C动)0.99>坐果濒危系数(C果)0.93>幼苗濒危系数(C苗)0.89>开花濒危系数(C花)0.88>活株濒危系数(C活)0.83>人为采挖濒危系数(C人)0.71>自然枯死濒危系数(C枯)0.53。调查结果显示,综合濒危系数为0.82,依据国际濒危物种等级新标准,处于濒危状态,其中野生动物危害较大和自我更新能力差是导致保护区内野生蕙兰濒危的主要因素,同时与人的因素也密不可分。[结论]建议建立以保护野生蕙兰为主的重点保护区域,积极开展以野生蕙兰种群恢复为主的科学研究;设立野生动物补饲点,减少对野生蕙兰资源的破坏;加大宣传力度,禁止非法采挖、放牧等人为干扰行为。

关键词：蕙兰野生资源濒危机制保护太宽河保护区

Role of oncogenic long noncoding RNA KCNQ1OT1 in colon cancer

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Oncology Research 2024年第3期32卷 585-596页

作者： gang LIU LEI shi BIN wang ZEHUI WU HAIYUAN ZHAO TIANYU ZHAO LIANGHUI shi Department of Gastrointestinal Surgery First ffiliated Hospital of Wannan Medical CollegeWuhu241001China Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences Stomatological Hospital of Chongqing Medical UniversityChongqing401147China

The role of lncRNA KCNQ1 opposite strand/antisense transcript 1(KCNQ1OT1)in colon cancer involves various tumorigenic processes and has been studed ***,the mechanism by which it promotes colon cancer remains *** vector pSEB61 was retroftted in established HCT116 siKCN and SW480-siKCN cells to silence KCNQ1 *** proliferation was measured using CCK8 assay,and flow cytometry(FCM)detected cell cydle *** sequencing(RNA Seq)analysis showed differentially expressed genes(DEGs).Gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were carried out to analyze enriched functions and signaling ***-qPCR,immunofluorescence,and western blotting were carried out to validate downstream gene *** effects of tumorigenesis were evaluated in BALB/c nude mice by tumor *** data revealed that the silencing of KONQ1OT1 in HCT116 and SW480 cells slowed cell growth and decreased the number of cells in the G2/M ***-Seq analysis showed the data of DEGs enriched in various GO and KEGG pathways such as DNA replication and cell *** qPCR,immunofluorescence,and western blotting confirmed downstream CCNE2 and PCNA gene ***116 siKCN cells signifcantly suppressed tumorigenesis in BALB/c nude *** study suggests that lncRNA KCNQ1OT1 may provide a promising therapeutic strategy for colon cancer.

关键词： lncRNA KCNQ1OT1 Colon cancer HCT116 cells Tumorigenesis

Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

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Acta Mechanica Solida Sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang shi-Wen Chen Si-He wang Zhen-Yuan Gong Jun Feng gang-Feng wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously shrinks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. However, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

Boosting propane dehydrogenation of defective S-1 stabilized singleatom Pt and ZnO catalysts via coordination environment regulation

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Nano Research 2024年第7期17卷 5884-5896页

作者： Fuwen Yang Jie Zhang Jinwei Chen gang wang Tong Yu Qian Li Zongbo shi Qiushi Sun Runsheng Zhuo Ruilin wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China Engineering Research Center of Alternative Energy Materials&Devices Ministry of EducationSichuan UniversityChengdu 610065China REZEL Catalysts Corporation Shanghai 200120China

Pt single atoms catalysts with precise coordination environment and high stability are expected to achieve high performance of propane dehydrogenation(PDH).In this work,an innovative synthetic strategy is proposed to construct the S-1@0.1Pt9Zn@DPS-1 nanocomposite as a highly efficient PDH *** engineering is applied to induce the formation of defective porous silicalite-1(DPS-1),which is favorable for achieving the uniformly distributed ZnO *** ZnO nanoclusters were further served as anchoring sites to stabilize the isolated Pt *** structural characterization revealed that penta-O coordinated Pt single atom coupled with ZnO nanoclusters decorated on the ***,the atomically dispersed Pt atoms with the ideal coordination environment could act as the predominant active sites for PDH *** expected,the optimal S-1@0.1Pt9Zn@DPS-1 catalyst delivered an excellent PDH performance(propane conversion of 40.7%,propylene selectivity of 97.5%)and good cycling regeneration *** work provides a new way for improving the activity and stability of catalysts in the field of industrial catalysts.

关键词： defect engineering single platinum atom coordination environment propane dehydrogenation propylene

Pulses in ground motions identified through surface partial matching and their impact on seismic rocking consequence

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 35-50页

作者： Tang Yuchuan wang Jiankang Wu gang School of Civil Engineering Southeast UniversityKey Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of EducationNanjing 211102China National and Local Joint Engineering Research Center for Intelligent Construction and Maintenance Nanjing 211102China

In seismology and earthquake engineering,it is fundamental to identify and characterize the pulse-like features in pulse-type ground *** capture the pulses that dominate structural responses,this study establishes congruence and shift relationships between response spectrum surfaces.A similarity search between spectrum surfaces,supplemented with a similarity search in time series,has been applied to characterize the pulse-like features in pulse-type ground *** identified pulses are tested in predicting the rocking consequences of slender rectangular blocks under the original ground ***,the prediction is promising for the majority of the ground motions where the dominant pulse is correctly identified.

关键词： velocity pulse ground motion surface similarity rocking overturning

Research progress in assessment and strategies for sustainable food system within planetary boundaries

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Science China Earth Sciences 2024年第2期67卷 375-386页

作者： Minglei wang Wenjiao shi Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China

Meeting the increasing food demand in a manner that ensures both resources and environmental sustainability poses a global *** conceptual framework of planetary boundaries(PBs)has emerged as a crucial reference in the study of sustainable food system,with specific focuses on key dimensions such as land use change,freshwater use,nitrogen(N)and phosphorus(P)cycles,and greenhouse gas(GHG)*** this study,we summarized the threshold applications of PBs in sustainable food system research at both the global and national(China)*** on these thresholds,we evaluated the sustainability conditions of the food system,considering resources such as cropland,freshwater,N and P applications,as well as environmental impacts including N and P losses,and GHG *** addition,we explored the impacts of single or combined management strategies on sustainable food *** strategies included dietary changes,improvements in technologies and management,reductions in food loss and waste,and optimization in agricultural production ***,we outlined future research directions in sustainable food system,including enhancing research on the interaction mechanisms among PBs elements within food systems,conducting downscaling studies of PBs elements at national and regional levels,and ensuring the rationality of policy-making for sustainable food systems in *** study can provide a theoretical foundation and strategies guidance for sustainable food system and agricultural land use management in the future both globally and in China.

关键词： Food system Resource use Environmental impacts Sustainable strategy Planetary boundaries

High corrosion and wear resistant electroless Ni–P gradient coatings on aviation aluminum alloy parts

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 155-164页

作者： Bo wang Jiawei Li Zhihui Xie Gengjie wang gang Yu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410012China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province/College of Chemistry and Chemical Engineering China West Normal UniversityNanchong 637002China Zhongchuan Machinery Ltd.Co. Aero Engine Corporation of ChinaChangsha 410200China

A Ni–P alloy gradient coating consisting of multiple electroless Ni–P layers with various phosphorus contents was prepared on the aviation aluminum alloy. Several characterization and electrochemical techniques were used to characterize the different Ni–P coatings’ morphologies, phase structures, elemental compositions, and corrosion protection. The gradient coating showed good adhesion and high corrosion and wear resistance, enabling the application of aluminum alloy in harsh environments. The results showed that the double zinc immersion was vital in obtaining excellent adhesion (81.2 N). The optimal coating was not peeled and shredded even after bending tests with angles higher than 90°and was not corroded visually after 500 h of neutral salt spray test at 35℃. The high corrosion resistance was attributed to the misaligning of these micro defects in the three different nickel alloy layers and the amorphous structure of the high P content in the outer layer. These findings guide the exploration of functional gradient coatings that meet the high application requirement of aluminum alloy parts in complicated and harsh aviation environments.

关键词： aluminum alloy electroless nickel coating corrosion adhesion